sig_pri.c

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/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 1999 - 2009, Digium, Inc.
 *
 * Mark Spencer <markster@digium.com>
 *
 * See http://www.asterisk.org for more information about
 * the Asterisk project. Please do not directly contact
 * any of the maintainers of this project for assistance;
 * the project provides a web site, mailing lists and IRC
 * channels for your use.
 *
 * This program is free software, distributed under the terms of
 * the GNU General Public License Version 2. See the LICENSE file
 * at the top of the source tree.
 */

/*! \file
 *
 * \brief PRI signaling module
 *
 * \author Matthew Fredrickson <creslin@digium.com>
 */

/*** MODULEINFO
   <support_level>core</support_level>
 ***/

#include "asterisk.h"

#ifdef HAVE_PRI

#include <errno.h>
#include <ctype.h>
#include <signal.h>

#include "asterisk/utils.h"
#include "asterisk/options.h"
#include "asterisk/pbx.h"
#include "asterisk/app.h"
#include "asterisk/file.h"
#include "asterisk/callerid.h"
#include "asterisk/say.h"
#include "asterisk/manager.h"
#include "asterisk/astdb.h"
#include "asterisk/causes.h"
#include "asterisk/musiconhold.h"
#include "asterisk/cli.h"
#include "asterisk/transcap.h"
#include "asterisk/features.h"
#include "asterisk/aoc.h"

#include "sig_pri.h"
#ifndef PRI_EVENT_FACILITY
#error "Upgrade your libpri"
#endif

/*** DOCUMENTATION
 ***/


/* define this to send PRI user-user information elements */
#undef SUPPORT_USERUSER

/*!
 * Define to make always pick a channel if allowed.  Useful for
 * testing channel shifting.
 */
//#define ALWAYS_PICK_CHANNEL 1

/*!
 * Define to force a RESTART on a channel that returns a cause
 * code of PRI_CAUSE_REQUESTED_CHAN_UNAVAIL(44).  If the cause
 * is because of a stuck channel on the peer and the channel is
 * always the next channel we pick for an outgoing call then
 * this can help.
 */
#define FORCE_RESTART_UNAVAIL_CHANS    1

#if defined(HAVE_PRI_CCSS)
struct sig_pri_cc_agent_prv {
   /*! Asterisk span D channel control structure. */
   struct sig_pri_span *pri;
   /*! CC id value to use with libpri. -1 if invalid. */
   long cc_id;
   /*! TRUE if CC has been requested and we are waiting for the response. */
   unsigned char cc_request_response_pending;
};

struct sig_pri_cc_monitor_instance {
   /*! \brief Asterisk span D channel control structure. */
   struct sig_pri_span *pri;
   /*! CC id value to use with libpri. (-1 if already canceled). */
   long cc_id;
   /*! CC core id value. */
   int core_id;
   /*! Device name(Channel name less sequence number) */
   char name[1];
};

/*! Upper level agent/monitor type name. */
static const char *sig_pri_cc_type_name;
/*! Container of sig_pri monitor instances. */
static struct ao2_container *sig_pri_cc_monitors;
#endif   /* defined(HAVE_PRI_CCSS) */

static int pri_matchdigittimeout = 3000;

static int pri_gendigittimeout = 8000;

#define DCHAN_NOTINALARM  (1 << 0)
#define DCHAN_UP          (1 << 1)

/* Defines to help decode the encoded event channel id. */
#define PRI_CHANNEL(p)  ((p) & 0xff)
#define PRI_SPAN(p)     (((p) >> 8) & 0xff)
#define PRI_EXPLICIT (1 << 16)
#define PRI_CIS_CALL (1 << 17)   /* Call is using the D channel only. */
#define PRI_HELD_CALL   (1 << 18)


#define DCHAN_AVAILABLE (DCHAN_NOTINALARM | DCHAN_UP)

static int pri_active_dchan_index(struct sig_pri_span *pri);

static const char *sig_pri_call_level2str(enum sig_pri_call_level level)
{
   switch (level) {
   case SIG_PRI_CALL_LEVEL_IDLE:
      return "Idle";
   case SIG_PRI_CALL_LEVEL_SETUP:
      return "Setup";
   case SIG_PRI_CALL_LEVEL_OVERLAP:
      return "Overlap";
   case SIG_PRI_CALL_LEVEL_PROCEEDING:
      return "Proceeding";
   case SIG_PRI_CALL_LEVEL_ALERTING:
      return "Alerting";
   case SIG_PRI_CALL_LEVEL_DEFER_DIAL:
      return "DeferDial";
   case SIG_PRI_CALL_LEVEL_CONNECT:
      return "Connect";
   }
   return "Unknown";
}

static inline void pri_rel(struct sig_pri_span *pri)
{
   ast_mutex_unlock(&pri->lock);
}

static unsigned int PVT_TO_CHANNEL(struct sig_pri_chan *p)
{
   int res = (((p)->prioffset) | ((p)->logicalspan << 8) | (p->mastertrunkgroup ? PRI_EXPLICIT : 0));
   ast_debug(5, "prioffset: %d mastertrunkgroup: %d logicalspan: %d result: %d\n",
      p->prioffset, p->mastertrunkgroup, p->logicalspan, res);

   return res;
}

static void sig_pri_handle_dchan_exception(struct sig_pri_span *pri, int index)
{
   if (sig_pri_callbacks.handle_dchan_exception) {
      sig_pri_callbacks.handle_dchan_exception(pri, index);
   }
}

static void sig_pri_set_dialing(struct sig_pri_chan *p, int is_dialing)
{
   if (sig_pri_callbacks.set_dialing) {
      sig_pri_callbacks.set_dialing(p->chan_pvt, is_dialing);
   }
}

static void sig_pri_set_digital(struct sig_pri_chan *p, int is_digital)
{
   p->digital = is_digital;
   if (sig_pri_callbacks.set_digital) {
      sig_pri_callbacks.set_digital(p->chan_pvt, is_digital);
   }
}

static void sig_pri_set_outgoing(struct sig_pri_chan *p, int is_outgoing)
{
   p->outgoing = is_outgoing;
   if (sig_pri_callbacks.set_outgoing) {
      sig_pri_callbacks.set_outgoing(p->chan_pvt, is_outgoing);
   }
}

void sig_pri_set_alarm(struct sig_pri_chan *p, int in_alarm)
{
   if (sig_pri_is_alarm_ignored(p->pri)) {
      /* Always set not in alarm */
      in_alarm = 0;
   }

   /*
    * Clear the channel restart state when the channel alarm
    * changes to prevent the state from getting stuck when the link
    * goes down.
    */
   p->resetting = SIG_PRI_RESET_IDLE;

   p->inalarm = in_alarm;
   if (sig_pri_callbacks.set_alarm) {
      sig_pri_callbacks.set_alarm(p->chan_pvt, in_alarm);
   }
}

static const char *sig_pri_get_orig_dialstring(struct sig_pri_chan *p)
{
   if (sig_pri_callbacks.get_orig_dialstring) {
      return sig_pri_callbacks.get_orig_dialstring(p->chan_pvt);
   }
   ast_log(LOG_ERROR, "get_orig_dialstring callback not defined\n");
   return "";
}

#if defined(HAVE_PRI_CCSS)
static void sig_pri_make_cc_dialstring(struct sig_pri_chan *p, char *buf, size_t buf_size)
{
   if (sig_pri_callbacks.make_cc_dialstring) {
      sig_pri_callbacks.make_cc_dialstring(p->chan_pvt, buf, buf_size);
   } else {
      ast_log(LOG_ERROR, "make_cc_dialstring callback not defined\n");
      buf[0] = '\0';
   }
}
#endif   /* defined(HAVE_PRI_CCSS) */

static void sig_pri_dial_digits(struct sig_pri_chan *p, const char *dial_string)
{
   if (sig_pri_callbacks.dial_digits) {
      sig_pri_callbacks.dial_digits(p->chan_pvt, dial_string);
   }
}

/*!
 * \internal
 * \brief Reevaluate the PRI span device state.
 * \since 1.8
 *
 * \param pri PRI span control structure.
 *
 * \return Nothing
 *
 * \note Assumes the pri->lock is already obtained.
 */
static void sig_pri_span_devstate_changed(struct sig_pri_span *pri)
{
   if (sig_pri_callbacks.update_span_devstate) {
      sig_pri_callbacks.update_span_devstate(pri);
   }
}

/*!
 * \internal
 * \brief Set the caller id information in the parent module.
 * \since 1.8
 *
 * \param p sig_pri channel structure.
 *
 * \return Nothing
 */
static void sig_pri_set_caller_id(struct sig_pri_chan *p)
{
   struct ast_party_caller caller;

   if (sig_pri_callbacks.set_callerid) {
      ast_party_caller_init(&caller);

      caller.id.name.str = p->cid_name;
      caller.id.name.presentation = p->callingpres;
      caller.id.name.valid = 1;

      caller.id.number.str = p->cid_num;
      caller.id.number.plan = p->cid_ton;
      caller.id.number.presentation = p->callingpres;
      caller.id.number.valid = 1;

      if (!ast_strlen_zero(p->cid_subaddr)) {
         caller.id.subaddress.valid = 1;
         //caller.id.subaddress.type = 0;/* nsap */
         //caller.id.subaddress.odd_even_indicator = 0;
         caller.id.subaddress.str = p->cid_subaddr;
      }
      caller.id.tag = p->user_tag;

      caller.ani.number.str = p->cid_ani;
      //caller.ani.number.plan = p->xxx;
      //caller.ani.number.presentation = p->xxx;
      caller.ani.number.valid = 1;

      caller.ani2 = p->cid_ani2;
      sig_pri_callbacks.set_callerid(p->chan_pvt, &caller);
   }
}

/*!
 * \internal
 * \brief Set the Dialed Number Identifier.
 * \since 1.8
 *
 * \param p sig_pri channel structure.
 * \param dnid Dialed Number Identifier string.
 *
 * \return Nothing
 */
static void sig_pri_set_dnid(struct sig_pri_chan *p, const char *dnid)
{
   if (sig_pri_callbacks.set_dnid) {
      sig_pri_callbacks.set_dnid(p->chan_pvt, dnid);
   }
}

/*!
 * \internal
 * \brief Set the Redirecting Directory Number Information Service (RDNIS).
 * \since 1.8
 *
 * \param p sig_pri channel structure.
 * \param rdnis Redirecting Directory Number Information Service (RDNIS) string.
 *
 * \return Nothing
 */
static void sig_pri_set_rdnis(struct sig_pri_chan *p, const char *rdnis)
{
   if (sig_pri_callbacks.set_rdnis) {
      sig_pri_callbacks.set_rdnis(p->chan_pvt, rdnis);
   }
}

static void sig_pri_unlock_private(struct sig_pri_chan *p)
{
   if (sig_pri_callbacks.unlock_private) {
      sig_pri_callbacks.unlock_private(p->chan_pvt);
   }
}

static void sig_pri_lock_private(struct sig_pri_chan *p)
{
   if (sig_pri_callbacks.lock_private) {
      sig_pri_callbacks.lock_private(p->chan_pvt);
   }
}

static void sig_pri_deadlock_avoidance_private(struct sig_pri_chan *p)
{
   if (sig_pri_callbacks.deadlock_avoidance_private) {
      sig_pri_callbacks.deadlock_avoidance_private(p->chan_pvt);
   } else {
      /* Fallback to the old way if callback not present. */
      sig_pri_unlock_private(p);
      sched_yield();
      sig_pri_lock_private(p);
   }
}

static void pri_grab(struct sig_pri_chan *p, struct sig_pri_span *pri)
{
   /* Grab the lock first */
   while (ast_mutex_trylock(&pri->lock)) {
      /* Avoid deadlock */
      sig_pri_deadlock_avoidance_private(p);
   }
   /* Then break the poll */
   if (pri->master != AST_PTHREADT_NULL) {
      pthread_kill(pri->master, SIGURG);
   }
}

/*!
 * \internal
 * \brief Convert PRI redirecting reason to asterisk version.
 * \since 1.8
 *
 * \param pri_reason PRI redirecting reason.
 *
 * \return Equivalent asterisk redirecting reason value.
 */
static enum AST_REDIRECTING_REASON pri_to_ast_reason(int pri_reason)
{
   enum AST_REDIRECTING_REASON ast_reason;

   switch (pri_reason) {
   case PRI_REDIR_FORWARD_ON_BUSY:
      ast_reason = AST_REDIRECTING_REASON_USER_BUSY;
      break;
   case PRI_REDIR_FORWARD_ON_NO_REPLY:
      ast_reason = AST_REDIRECTING_REASON_NO_ANSWER;
      break;
   case PRI_REDIR_DEFLECTION:
      ast_reason = AST_REDIRECTING_REASON_DEFLECTION;
      break;
   case PRI_REDIR_UNCONDITIONAL:
      ast_reason = AST_REDIRECTING_REASON_UNCONDITIONAL;
      break;
   case PRI_REDIR_UNKNOWN:
   default:
      ast_reason = AST_REDIRECTING_REASON_UNKNOWN;
      break;
   }

   return ast_reason;
}

/*!
 * \internal
 * \brief Convert asterisk redirecting reason to PRI version.
 * \since 1.8
 *
 * \param ast_reason Asterisk redirecting reason.
 *
 * \return Equivalent PRI redirecting reason value.
 */
static int ast_to_pri_reason(enum AST_REDIRECTING_REASON ast_reason)
{
   int pri_reason;

   switch (ast_reason) {
   case AST_REDIRECTING_REASON_USER_BUSY:
      pri_reason = PRI_REDIR_FORWARD_ON_BUSY;
      break;
   case AST_REDIRECTING_REASON_NO_ANSWER:
      pri_reason = PRI_REDIR_FORWARD_ON_NO_REPLY;
      break;
   case AST_REDIRECTING_REASON_UNCONDITIONAL:
      pri_reason = PRI_REDIR_UNCONDITIONAL;
      break;
   case AST_REDIRECTING_REASON_DEFLECTION:
      pri_reason = PRI_REDIR_DEFLECTION;
      break;
   case AST_REDIRECTING_REASON_UNKNOWN:
   default:
      pri_reason = PRI_REDIR_UNKNOWN;
      break;
   }

   return pri_reason;
}

/*!
 * \internal
 * \brief Convert PRI number presentation to asterisk version.
 * \since 1.8
 *
 * \param pri_presentation PRI number presentation.
 *
 * \return Equivalent asterisk number presentation value.
 */
static int pri_to_ast_presentation(int pri_presentation)
{
   int ast_presentation;

   switch (pri_presentation) {
   case PRI_PRES_ALLOWED | PRI_PRES_USER_NUMBER_UNSCREENED:
      ast_presentation = AST_PRES_ALLOWED | AST_PRES_USER_NUMBER_UNSCREENED;
      break;
   case PRI_PRES_ALLOWED | PRI_PRES_USER_NUMBER_PASSED_SCREEN:
      ast_presentation = AST_PRES_ALLOWED | AST_PRES_USER_NUMBER_PASSED_SCREEN;
      break;
   case PRI_PRES_ALLOWED | PRI_PRES_USER_NUMBER_FAILED_SCREEN:
      ast_presentation = AST_PRES_ALLOWED | AST_PRES_USER_NUMBER_FAILED_SCREEN;
      break;
   case PRI_PRES_ALLOWED | PRI_PRES_NETWORK_NUMBER:
      ast_presentation = AST_PRES_ALLOWED | AST_PRES_NETWORK_NUMBER;
      break;

   case PRI_PRES_RESTRICTED | PRI_PRES_USER_NUMBER_UNSCREENED:
      ast_presentation = AST_PRES_RESTRICTED | AST_PRES_USER_NUMBER_UNSCREENED;
      break;
   case PRI_PRES_RESTRICTED | PRI_PRES_USER_NUMBER_PASSED_SCREEN:
      ast_presentation = AST_PRES_RESTRICTED | AST_PRES_USER_NUMBER_PASSED_SCREEN;
      break;
   case PRI_PRES_RESTRICTED | PRI_PRES_USER_NUMBER_FAILED_SCREEN:
      ast_presentation = AST_PRES_RESTRICTED | AST_PRES_USER_NUMBER_FAILED_SCREEN;
      break;
   case PRI_PRES_RESTRICTED | PRI_PRES_NETWORK_NUMBER:
      ast_presentation = AST_PRES_RESTRICTED | AST_PRES_NETWORK_NUMBER;
      break;

   case PRI_PRES_UNAVAILABLE | PRI_PRES_USER_NUMBER_UNSCREENED:
   case PRI_PRES_UNAVAILABLE | PRI_PRES_USER_NUMBER_PASSED_SCREEN:
   case PRI_PRES_UNAVAILABLE | PRI_PRES_USER_NUMBER_FAILED_SCREEN:
   case PRI_PRES_UNAVAILABLE | PRI_PRES_NETWORK_NUMBER:
      ast_presentation = AST_PRES_NUMBER_NOT_AVAILABLE;
      break;

   default:
      ast_presentation = AST_PRES_RESTRICTED | AST_PRES_USER_NUMBER_UNSCREENED;
      break;
   }

   return ast_presentation;
}

/*!
 * \internal
 * \brief Convert asterisk number presentation to PRI version.
 * \since 1.8
 *
 * \param ast_presentation Asterisk number presentation.
 *
 * \return Equivalent PRI number presentation value.
 */
static int ast_to_pri_presentation(int ast_presentation)
{
   int pri_presentation;

   switch (ast_presentation) {
   case AST_PRES_ALLOWED | AST_PRES_USER_NUMBER_UNSCREENED:
      pri_presentation = PRI_PRES_ALLOWED | PRI_PRES_USER_NUMBER_UNSCREENED;
      break;
   case AST_PRES_ALLOWED | AST_PRES_USER_NUMBER_PASSED_SCREEN:
      pri_presentation = PRI_PRES_ALLOWED | PRI_PRES_USER_NUMBER_PASSED_SCREEN;
      break;
   case AST_PRES_ALLOWED | AST_PRES_USER_NUMBER_FAILED_SCREEN:
      pri_presentation = PRI_PRES_ALLOWED | PRI_PRES_USER_NUMBER_FAILED_SCREEN;
      break;
   case AST_PRES_ALLOWED | AST_PRES_NETWORK_NUMBER:
      pri_presentation = PRI_PRES_ALLOWED | PRI_PRES_NETWORK_NUMBER;
      break;

   case AST_PRES_RESTRICTED | AST_PRES_USER_NUMBER_UNSCREENED:
      pri_presentation = PRI_PRES_RESTRICTED | PRI_PRES_USER_NUMBER_UNSCREENED;
      break;
   case AST_PRES_RESTRICTED | AST_PRES_USER_NUMBER_PASSED_SCREEN:
      pri_presentation = PRI_PRES_RESTRICTED | PRI_PRES_USER_NUMBER_PASSED_SCREEN;
      break;
   case AST_PRES_RESTRICTED | AST_PRES_USER_NUMBER_FAILED_SCREEN:
      pri_presentation = PRI_PRES_RESTRICTED | PRI_PRES_USER_NUMBER_FAILED_SCREEN;
      break;
   case AST_PRES_RESTRICTED | AST_PRES_NETWORK_NUMBER:
      pri_presentation = PRI_PRES_RESTRICTED | PRI_PRES_NETWORK_NUMBER;
      break;

   case AST_PRES_UNAVAILABLE | AST_PRES_USER_NUMBER_UNSCREENED:
   case AST_PRES_UNAVAILABLE | AST_PRES_USER_NUMBER_PASSED_SCREEN:
   case AST_PRES_UNAVAILABLE | AST_PRES_USER_NUMBER_FAILED_SCREEN:
   case AST_PRES_UNAVAILABLE | AST_PRES_NETWORK_NUMBER:
      pri_presentation = PRES_NUMBER_NOT_AVAILABLE;
      break;

   default:
      pri_presentation = PRI_PRES_RESTRICTED | PRI_PRES_USER_NUMBER_UNSCREENED;
      break;
   }

   return pri_presentation;
}

/*!
 * \internal
 * \brief Convert PRI name char_set to asterisk version.
 * \since 1.8
 *
 * \param pri_char_set PRI name char_set.
 *
 * \return Equivalent asterisk name char_set value.
 */
static enum AST_PARTY_CHAR_SET pri_to_ast_char_set(int pri_char_set)
{
   enum AST_PARTY_CHAR_SET ast_char_set;

   switch (pri_char_set) {
   default:
   case PRI_CHAR_SET_UNKNOWN:
      ast_char_set = AST_PARTY_CHAR_SET_UNKNOWN;
      break;
   case PRI_CHAR_SET_ISO8859_1:
      ast_char_set = AST_PARTY_CHAR_SET_ISO8859_1;
      break;
   case PRI_CHAR_SET_WITHDRAWN:
      ast_char_set = AST_PARTY_CHAR_SET_WITHDRAWN;
      break;
   case PRI_CHAR_SET_ISO8859_2:
      ast_char_set = AST_PARTY_CHAR_SET_ISO8859_2;
      break;
   case PRI_CHAR_SET_ISO8859_3:
      ast_char_set = AST_PARTY_CHAR_SET_ISO8859_3;
      break;
   case PRI_CHAR_SET_ISO8859_4:
      ast_char_set = AST_PARTY_CHAR_SET_ISO8859_4;
      break;
   case PRI_CHAR_SET_ISO8859_5:
      ast_char_set = AST_PARTY_CHAR_SET_ISO8859_5;
      break;
   case PRI_CHAR_SET_ISO8859_7:
      ast_char_set = AST_PARTY_CHAR_SET_ISO8859_7;
      break;
   case PRI_CHAR_SET_ISO10646_BMPSTRING:
      ast_char_set = AST_PARTY_CHAR_SET_ISO10646_BMPSTRING;
      break;
   case PRI_CHAR_SET_ISO10646_UTF_8STRING:
      ast_char_set = AST_PARTY_CHAR_SET_ISO10646_UTF_8STRING;
      break;
   }

   return ast_char_set;
}

/*!
 * \internal
 * \brief Convert asterisk name char_set to PRI version.
 * \since 1.8
 *
 * \param ast_char_set Asterisk name char_set.
 *
 * \return Equivalent PRI name char_set value.
 */
static int ast_to_pri_char_set(enum AST_PARTY_CHAR_SET ast_char_set)
{
   int pri_char_set;

   switch (ast_char_set) {
   default:
   case AST_PARTY_CHAR_SET_UNKNOWN:
      pri_char_set = PRI_CHAR_SET_UNKNOWN;
      break;
   case AST_PARTY_CHAR_SET_ISO8859_1:
      pri_char_set = PRI_CHAR_SET_ISO8859_1;
      break;
   case AST_PARTY_CHAR_SET_WITHDRAWN:
      pri_char_set = PRI_CHAR_SET_WITHDRAWN;
      break;
   case AST_PARTY_CHAR_SET_ISO8859_2:
      pri_char_set = PRI_CHAR_SET_ISO8859_2;
      break;
   case AST_PARTY_CHAR_SET_ISO8859_3:
      pri_char_set = PRI_CHAR_SET_ISO8859_3;
      break;
   case AST_PARTY_CHAR_SET_ISO8859_4:
      pri_char_set = PRI_CHAR_SET_ISO8859_4;
      break;
   case AST_PARTY_CHAR_SET_ISO8859_5:
      pri_char_set = PRI_CHAR_SET_ISO8859_5;
      break;
   case AST_PARTY_CHAR_SET_ISO8859_7:
      pri_char_set = PRI_CHAR_SET_ISO8859_7;
      break;
   case AST_PARTY_CHAR_SET_ISO10646_BMPSTRING:
      pri_char_set = PRI_CHAR_SET_ISO10646_BMPSTRING;
      break;
   case AST_PARTY_CHAR_SET_ISO10646_UTF_8STRING:
      pri_char_set = PRI_CHAR_SET_ISO10646_UTF_8STRING;
      break;
   }

   return pri_char_set;
}

#if defined(HAVE_PRI_SUBADDR)
/*!
 * \internal
 * \brief Fill in the asterisk party subaddress from the given PRI party subaddress.
 * \since 1.8
 *
 * \param ast_subaddress Asterisk party subaddress structure.
 * \param pri_subaddress PRI party subaddress structure.
 *
 * \return Nothing
 *
 */
static void sig_pri_set_subaddress(struct ast_party_subaddress *ast_subaddress, const struct pri_party_subaddress *pri_subaddress)
{
   ast_free(ast_subaddress->str);
   if (pri_subaddress->length <= 0) {
      ast_party_subaddress_init(ast_subaddress);
      return;
   }

   if (!pri_subaddress->type) {
      /* NSAP */
      ast_subaddress->str = ast_strdup((char *) pri_subaddress->data);
   } else {
      char *cnum;
      char *ptr;
      int x;
      int len;

      /* User Specified */
      cnum = ast_malloc(2 * pri_subaddress->length + 1);
      if (!cnum) {
         ast_party_subaddress_init(ast_subaddress);
         return;
      }

      ptr = cnum;
      len = pri_subaddress->length - 1; /* -1 account for zero based indexing */
      for (x = 0; x < len; ++x) {
         ptr += sprintf(ptr, "%02x", pri_subaddress->data[x]);
      }

      if (pri_subaddress->odd_even_indicator) {
         /* ODD */
         sprintf(ptr, "%01x", (pri_subaddress->data[len]) >> 4);
      } else {
         /* EVEN */
         sprintf(ptr, "%02x", pri_subaddress->data[len]);
      }
      ast_subaddress->str = cnum;
   }
   ast_subaddress->type = pri_subaddress->type;
   ast_subaddress->odd_even_indicator = pri_subaddress->odd_even_indicator;
   ast_subaddress->valid = 1;
}
#endif   /* defined(HAVE_PRI_SUBADDR) */

#if defined(HAVE_PRI_SUBADDR)
static unsigned char ast_pri_pack_hex_char(char c)
{
   unsigned char res;

   if (c < '0') {
      res = 0;
   } else if (c < ('9' + 1)) {
      res = c - '0';
   } else if (c < 'A') {
      res = 0;
   } else if (c < ('F' + 1)) {
      res = c - 'A' + 10;
   } else if (c < 'a') {
      res = 0;
   } else if (c < ('f' + 1)) {
      res = c - 'a' + 10;
   } else {
      res = 0;
   }
   return res;
}
#endif   /* defined(HAVE_PRI_SUBADDR) */

#if defined(HAVE_PRI_SUBADDR)
/*!
 * \internal
 * \brief Convert a null terminated hexadecimal string to a packed hex byte array.
 * \details left justified, with 0 padding if odd length.
 * \since 1.8
 *
 * \param dst pointer to packed byte array.
 * \param src pointer to null terminated hexadecimal string.
 * \param maxlen destination array size.
 *
 * \return Length of byte array
 *
 * \note The dst is not an ASCIIz string.
 * \note The src is an ASCIIz hex string.
 */
static int ast_pri_pack_hex_string(unsigned char *dst, char *src, int maxlen)
{
   int res = 0;
   int len = strlen(src);

   if (len > (2 * maxlen)) {
      len = 2 * maxlen;
   }

   res = len / 2 + len % 2;

   while (len > 1) {
      *dst = ast_pri_pack_hex_char(*src) << 4;
      src++;
      *dst |= ast_pri_pack_hex_char(*src);
      dst++, src++;
      len -= 2;
   }
   if (len) { /* 1 left */
      *dst = ast_pri_pack_hex_char(*src) << 4;
   }
   return res;
}
#endif   /* defined(HAVE_PRI_SUBADDR) */

#if defined(HAVE_PRI_SUBADDR)
/*!
 * \internal
 * \brief Fill in the PRI party subaddress from the given asterisk party subaddress.
 * \since 1.8
 *
 * \param pri_subaddress PRI party subaddress structure.
 * \param ast_subaddress Asterisk party subaddress structure.
 *
 * \return Nothing
 *
 * \note Assumes that pri_subaddress has been previously memset to zero.
 */
static void sig_pri_party_subaddress_from_ast(struct pri_party_subaddress *pri_subaddress, const struct ast_party_subaddress *ast_subaddress)
{
   if (ast_subaddress->valid && !ast_strlen_zero(ast_subaddress->str)) {
      pri_subaddress->type = ast_subaddress->type;
      if (!ast_subaddress->type) {
         /* 0 = NSAP */
         ast_copy_string((char *) pri_subaddress->data, ast_subaddress->str,
            sizeof(pri_subaddress->data));
         pri_subaddress->length = strlen((char *) pri_subaddress->data);
         pri_subaddress->odd_even_indicator = 0;
         pri_subaddress->valid = 1;
      } else {
         /* 2 = User Specified */
         /*
          * Copy HexString to packed HexData,
          * if odd length then right pad trailing byte with 0
          */
         int length = ast_pri_pack_hex_string(pri_subaddress->data,
            ast_subaddress->str, sizeof(pri_subaddress->data));

         pri_subaddress->length = length; /* packed data length */

         length = strlen(ast_subaddress->str);
         if (length > 2 * sizeof(pri_subaddress->data)) {
            pri_subaddress->odd_even_indicator = 0;
         } else {
            pri_subaddress->odd_even_indicator = (length & 1);
         }
         pri_subaddress->valid = 1;
      }
   }
}
#endif   /* defined(HAVE_PRI_SUBADDR) */

/*!
 * \internal
 * \brief Fill in the PRI party name from the given asterisk party name.
 * \since 1.8
 *
 * \param pri_name PRI party name structure.
 * \param ast_name Asterisk party name structure.
 *
 * \return Nothing
 *
 * \note Assumes that pri_name has been previously memset to zero.
 */
static void sig_pri_party_name_from_ast(struct pri_party_name *pri_name, const struct ast_party_name *ast_name)
{
   if (!ast_name->valid) {
      return;
   }
   pri_name->valid = 1;
   pri_name->presentation = ast_to_pri_presentation(ast_name->presentation);
   pri_name->char_set = ast_to_pri_char_set(ast_name->char_set);
   if (!ast_strlen_zero(ast_name->str)) {
      ast_copy_string(pri_name->str, ast_name->str, sizeof(pri_name->str));
   }
}

/*!
 * \internal
 * \brief Fill in the PRI party number from the given asterisk party number.
 * \since 1.8
 *
 * \param pri_number PRI party number structure.
 * \param ast_number Asterisk party number structure.
 *
 * \return Nothing
 *
 * \note Assumes that pri_number has been previously memset to zero.
 */
static void sig_pri_party_number_from_ast(struct pri_party_number *pri_number, const struct ast_party_number *ast_number)
{
   if (!ast_number->valid) {
      return;
   }
   pri_number->valid = 1;
   pri_number->presentation = ast_to_pri_presentation(ast_number->presentation);
   pri_number->plan = ast_number->plan;
   if (!ast_strlen_zero(ast_number->str)) {
      ast_copy_string(pri_number->str, ast_number->str, sizeof(pri_number->str));
   }
}

/*!
 * \internal
 * \brief Fill in the PRI party id from the given asterisk party id.
 * \since 1.8
 *
 * \param pri_id PRI party id structure.
 * \param ast_id Asterisk party id structure.
 *
 * \return Nothing
 *
 * \note Assumes that pri_id has been previously memset to zero.
 */
static void sig_pri_party_id_from_ast(struct pri_party_id *pri_id, const struct ast_party_id *ast_id)
{
   sig_pri_party_name_from_ast(&pri_id->name, &ast_id->name);
   sig_pri_party_number_from_ast(&pri_id->number, &ast_id->number);
#if defined(HAVE_PRI_SUBADDR)
   sig_pri_party_subaddress_from_ast(&pri_id->subaddress, &ast_id->subaddress);
#endif   /* defined(HAVE_PRI_SUBADDR) */
}

/*!
 * \internal
 * \brief Update the PRI redirecting information for the current call.
 * \since 1.8
 *
 * \param pvt sig_pri private channel structure.
 * \param ast Asterisk channel
 *
 * \return Nothing
 *
 * \note Assumes that the PRI lock is already obtained.
 */
static void sig_pri_redirecting_update(struct sig_pri_chan *pvt, struct ast_channel *ast)
{
   struct pri_party_redirecting pri_redirecting;
   const struct ast_party_redirecting *ast_redirecting;
   struct ast_party_id redirecting_from = ast_channel_redirecting_effective_from(ast);
   struct ast_party_id redirecting_to = ast_channel_redirecting_effective_to(ast);
   struct ast_party_id redirecting_orig = ast_channel_redirecting_effective_orig(ast);

   memset(&pri_redirecting, 0, sizeof(pri_redirecting));
   ast_redirecting = ast_channel_redirecting(ast);
   sig_pri_party_id_from_ast(&pri_redirecting.from, &redirecting_from);
   sig_pri_party_id_from_ast(&pri_redirecting.to, &redirecting_to);
   sig_pri_party_id_from_ast(&pri_redirecting.orig_called, &redirecting_orig);
   pri_redirecting.count = ast_redirecting->count;
   pri_redirecting.orig_reason = ast_to_pri_reason(ast_redirecting->orig_reason);
   pri_redirecting.reason = ast_to_pri_reason(ast_redirecting->reason);

   pri_redirecting_update(pvt->pri->pri, pvt->call, &pri_redirecting);
}

/*!
 * \internal
 * \brief Reset DTMF detector.
 * \since 1.8
 *
 * \param p sig_pri channel structure.
 *
 * \return Nothing
 */
static void sig_pri_dsp_reset_and_flush_digits(struct sig_pri_chan *p)
{
   if (sig_pri_callbacks.dsp_reset_and_flush_digits) {
      sig_pri_callbacks.dsp_reset_and_flush_digits(p->chan_pvt);
   }
}

static int sig_pri_set_echocanceller(struct sig_pri_chan *p, int enable)
{
   if (sig_pri_callbacks.set_echocanceller) {
      return sig_pri_callbacks.set_echocanceller(p->chan_pvt, enable);
   } else {
      return -1;
   }
}

static void sig_pri_fixup_chans(struct sig_pri_chan *old_chan, struct sig_pri_chan *new_chan)
{
   if (sig_pri_callbacks.fixup_chans) {
      sig_pri_callbacks.fixup_chans(old_chan->chan_pvt, new_chan->chan_pvt);
   }
}

static int sig_pri_play_tone(struct sig_pri_chan *p, enum sig_pri_tone tone)
{
   if (sig_pri_callbacks.play_tone) {
      return sig_pri_callbacks.play_tone(p->chan_pvt, tone);
   } else {
      return -1;
   }
}

static struct ast_channel *sig_pri_new_ast_channel(struct sig_pri_chan *p, int state, int ulaw, int transfercapability, char *exten, const struct ast_channel *requestor)
{
   struct ast_channel *c;

   if (sig_pri_callbacks.new_ast_channel) {
      c = sig_pri_callbacks.new_ast_channel(p->chan_pvt, state, ulaw, exten, requestor);
   } else {
      return NULL;
   }
   if (!c) {
      return NULL;
   }

   if (!p->owner)
      p->owner = c;
   p->isidlecall = 0;
   p->alreadyhungup = 0;
   ast_channel_transfercapability_set(c, transfercapability);
   pbx_builtin_setvar_helper(c, "TRANSFERCAPABILITY",
      ast_transfercapability2str(transfercapability));
   if (transfercapability & AST_TRANS_CAP_DIGITAL) {
      sig_pri_set_digital(p, 1);
   }
   if (p->pri) {
      ast_mutex_lock(&p->pri->lock);
      sig_pri_span_devstate_changed(p->pri);
      ast_mutex_unlock(&p->pri->lock);
   }

   return c;
}

/*!
 * \internal
 * \brief Open the PRI channel media path.
 * \since 1.8
 *
 * \param p Channel private control structure.
 *
 * \return Nothing
 */
static void sig_pri_open_media(struct sig_pri_chan *p)
{
   if (p->no_b_channel) {
      return;
   }

   if (sig_pri_callbacks.open_media) {
      sig_pri_callbacks.open_media(p->chan_pvt);
   }
}

/*!
 * \internal
 * \brief Post an AMI B channel association event.
 * \since 1.8
 *
 * \param p Channel private control structure.
 *
 * \note Assumes the private and owner are locked.
 *
 * \return Nothing
 */
static void sig_pri_ami_channel_event(struct sig_pri_chan *p)
{
   if (sig_pri_callbacks.ami_channel_event) {
      sig_pri_callbacks.ami_channel_event(p->chan_pvt, p->owner);
   }
}

struct ast_channel *sig_pri_request(struct sig_pri_chan *p, enum sig_pri_law law, const struct ast_channel *requestor, int transfercapability)
{
   struct ast_channel *ast;

   ast_debug(1, "%s %d\n", __FUNCTION__, p->channel);

   sig_pri_set_outgoing(p, 1);
   ast = sig_pri_new_ast_channel(p, AST_STATE_RESERVED, law, transfercapability, p->exten, requestor);
   if (!ast) {
      sig_pri_set_outgoing(p, 0);
   }
   return ast;
}

int pri_is_up(struct sig_pri_span *pri)
{
   int x;
   for (x = 0; x < SIG_PRI_NUM_DCHANS; x++) {
      if (pri->dchanavail[x] == DCHAN_AVAILABLE)
         return 1;
   }
   return 0;
}

static const char *pri_order(int level)
{
   switch (level) {
   case 0:
      return "Primary";
   case 1:
      return "Secondary";
   case 2:
      return "Tertiary";
   case 3:
      return "Quaternary";
   default:
      return "<Unknown>";
   }
}

/* Returns index of the active dchan */
static int pri_active_dchan_index(struct sig_pri_span *pri)
{
   int x;

   for (x = 0; x < SIG_PRI_NUM_DCHANS; x++) {
      if ((pri->dchans[x] == pri->pri))
         return x;
   }

   ast_log(LOG_WARNING, "No active dchan found!\n");
   return -1;
}

static void pri_find_dchan(struct sig_pri_span *pri)
{
   struct pri *old;
   int oldslot = -1;
   int newslot = -1;
   int idx;

   old = pri->pri;
   for (idx = 0; idx < SIG_PRI_NUM_DCHANS; ++idx) {
      if (!pri->dchans[idx]) {
         /* No more D channels defined on the span. */
         break;
      }
      if (pri->dchans[idx] == old) {
         oldslot = idx;
      }
      if (newslot < 0 && pri->dchanavail[idx] == DCHAN_AVAILABLE) {
         newslot = idx;
      }
   }
   /* At this point, idx is a count of how many D-channels are defined on the span. */

   if (1 < idx) {
      /* We have several D-channels defined on the span.  (NFAS PRI setup) */
      if (newslot < 0) {
         /* No D-channels available.  Default to the primary D-channel. */
         newslot = 0;

         if (!pri->no_d_channels) {
            pri->no_d_channels = 1;
            if (old && oldslot != newslot) {
               ast_log(LOG_WARNING,
                  "Span %d: No D-channels up!  Switching selected D-channel from %s to %s.\n",
                  pri->span, pri_order(oldslot), pri_order(newslot));
            } else {
               ast_log(LOG_WARNING, "Span %d: No D-channels up!\n", pri->span);
            }
         }
      } else {
         pri->no_d_channels = 0;
      }
      if (old && oldslot != newslot) {
         ast_log(LOG_NOTICE,
            "Switching selected D-channel from %s (fd %d) to %s (fd %d)!\n",
            pri_order(oldslot), pri->fds[oldslot],
            pri_order(newslot), pri->fds[newslot]);
      }
   } else {
      if (newslot < 0) {
         /* The only D-channel is not up. */
         newslot = 0;

         if (!pri->no_d_channels) {
            pri->no_d_channels = 1;

            /*
             * This is annoying to see on non-persistent layer 2
             * connections.  Let's not complain in that case.
             */
            if (pri->sig != SIG_BRI_PTMP) {
               ast_log(LOG_WARNING, "Span %d: D-channel is down!\n", pri->span);
            }
         }
      } else {
         pri->no_d_channels = 0;
      }
   }
   pri->pri = pri->dchans[newslot];
}

/*!
 * \internal
 * \brief Determine if a private channel structure is in use.
 * \since 1.8
 *
 * \param pvt Channel to determine if in use.
 *
 * \return TRUE if the channel is in use.
 */
static int sig_pri_is_chan_in_use(struct sig_pri_chan *pvt)
{
   return pvt->owner || pvt->call || pvt->allocated || pvt->inalarm
      || pvt->resetting != SIG_PRI_RESET_IDLE;
}

/*!
 * \brief Determine if a private channel structure is available.
 * \since 1.8
 *
 * \param pvt Channel to determine if available.
 *
 * \return TRUE if the channel is available.
 */
int sig_pri_is_chan_available(struct sig_pri_chan *pvt)
{
   return !sig_pri_is_chan_in_use(pvt)
#if defined(HAVE_PRI_SERVICE_MESSAGES)
      /* And not out-of-service */
      && !pvt->service_status
#endif   /* defined(HAVE_PRI_SERVICE_MESSAGES) */
      ;
}

/*!
 * \internal
 * \brief Obtain the sig_pri owner channel lock if the owner exists.
 * \since 1.8
 *
 * \param pri PRI span control structure.
 * \param chanpos Channel position in the span.
 *
 * \note Assumes the pri->lock is already obtained.
 * \note Assumes the sig_pri_lock_private(pri->pvts[chanpos]) is already obtained.
 *
 * \return Nothing
 */
static void sig_pri_lock_owner(struct sig_pri_span *pri, int chanpos)
{
   for (;;) {
      if (!pri->pvts[chanpos]->owner) {
         /* There is no owner lock to get. */
         break;
      }
      if (!ast_channel_trylock(pri->pvts[chanpos]->owner)) {
         /* We got the lock */
         break;
      }

      /* Avoid deadlock */
      sig_pri_unlock_private(pri->pvts[chanpos]);
      DEADLOCK_AVOIDANCE(&pri->lock);
      sig_pri_lock_private(pri->pvts[chanpos]);
   }
}

/*!
 * \internal
 * \brief Queue the given frame onto the owner channel.
 * \since 1.8
 *
 * \param pri PRI span control structure.
 * \param chanpos Channel position in the span.
 * \param frame Frame to queue onto the owner channel.
 *
 * \note Assumes the pri->lock is already obtained.
 * \note Assumes the sig_pri_lock_private(pri->pvts[chanpos]) is already obtained.
 *
 * \return Nothing
 */
static void pri_queue_frame(struct sig_pri_span *pri, int chanpos, struct ast_frame *frame)
{
   sig_pri_lock_owner(pri, chanpos);
   if (pri->pvts[chanpos]->owner) {
      ast_queue_frame(pri->pvts[chanpos]->owner, frame);
      ast_channel_unlock(pri->pvts[chanpos]->owner);
   }
}

/*!
 * \internal
 * \brief Queue a control frame of the specified subclass onto the owner channel.
 * \since 1.8
 *
 * \param pri PRI span control structure.
 * \param chanpos Channel position in the span.
 * \param subclass Control frame subclass to queue onto the owner channel.
 *
 * \note Assumes the pri->lock is already obtained.
 * \note Assumes the sig_pri_lock_private(pri->pvts[chanpos]) is already obtained.
 *
 * \return Nothing
 */
static void pri_queue_control(struct sig_pri_span *pri, int chanpos, int subclass)
{
   struct ast_frame f = {AST_FRAME_CONTROL, };
   struct sig_pri_chan *p = pri->pvts[chanpos];

   if (sig_pri_callbacks.queue_control) {
      sig_pri_callbacks.queue_control(p->chan_pvt, subclass);
   }

   f.subclass.integer = subclass;
   pri_queue_frame(pri, chanpos, &f);
}

/*!
 * \internal
 * \brief Queue a PVT_CAUSE_CODE frame onto the owner channel.
 * \since 11
 *
 * \param pri PRI span control structure.
 * \param chanpos Channel position in the span.
 * \param cause String describing the cause to be placed into the frame.
 *
 * \note Assumes the pri->lock is already obtained.
 * \note Assumes the sig_pri_lock_private(pri->pvts[chanpos]) is already obtained.
 *
 * \return Nothing
 */
static void pri_queue_pvt_cause_data(struct sig_pri_span *pri, int chanpos, const char *cause, int ast_cause)
{
   struct ast_channel *chan;
   struct ast_control_pvt_cause_code *cause_code;

   sig_pri_lock_owner(pri, chanpos);
   chan = pri->pvts[chanpos]->owner;
   if (chan) {
      int datalen = sizeof(*cause_code) + strlen(cause);
      cause_code = ast_alloca(datalen);
      memset(cause_code, 0, datalen);
      cause_code->ast_cause = ast_cause;
      ast_copy_string(cause_code->chan_name, ast_channel_name(chan), AST_CHANNEL_NAME);
      ast_copy_string(cause_code->code, cause, datalen + 1 - sizeof(*cause_code));
      ast_queue_control_data(chan, AST_CONTROL_PVT_CAUSE_CODE, cause_code, datalen);
      ast_channel_hangupcause_hash_set(chan, cause_code, datalen);
      ast_channel_unlock(chan);
   }
}

/*!
 * \internal
 * \brief Find the channel associated with the libpri call.
 * \since 10.0
 *
 * \param pri PRI span control structure.
 * \param call LibPRI opaque call pointer to find.
 *
 * \note Assumes the pri->lock is already obtained.
 *
 * \retval array-index into private pointer array on success.
 * \retval -1 on error.
 */
static int pri_find_principle_by_call(struct sig_pri_span *pri, q931_call *call)
{
   int idx;

   if (!call) {
      /* Cannot find a call without a call. */
      return -1;
   }
   for (idx = 0; idx < pri->numchans; ++idx) {
      if (pri->pvts[idx] && pri->pvts[idx]->call == call) {
         /* Found the principle */
         return idx;
      }
   }
   return -1;
}

/*!
 * \internal
 * \brief Kill the call.
 * \since 10.0
 *
 * \param pri PRI span control structure.
 * \param call LibPRI opaque call pointer to find.
 * \param cause Reason call was killed.
 *
 * \note Assumes the pvt->pri->lock is already obtained.
 *
 * \return Nothing
 */
static void sig_pri_kill_call(struct sig_pri_span *pri, q931_call *call, int cause)
{
   int chanpos;

   chanpos = pri_find_principle_by_call(pri, call);
   if (chanpos < 0) {
      pri_hangup(pri->pri, call, cause);
      return;
   }
   sig_pri_lock_private(pri->pvts[chanpos]);
   if (!pri->pvts[chanpos]->owner) {
      pri_hangup(pri->pri, call, cause);
      pri->pvts[chanpos]->call = NULL;
      sig_pri_unlock_private(pri->pvts[chanpos]);
      sig_pri_span_devstate_changed(pri);
      return;
   }
   ast_channel_hangupcause_set(pri->pvts[chanpos]->owner, cause);
   pri_queue_control(pri, chanpos, AST_CONTROL_HANGUP);
   sig_pri_unlock_private(pri->pvts[chanpos]);
}

/*!
 * \internal
 * \brief Find the private structure for the libpri call.
 *
 * \param pri PRI span control structure.
 * \param channel LibPRI encoded channel ID.
 * \param call LibPRI opaque call pointer.
 *
 * \note Assumes the pri->lock is already obtained.
 *
 * \retval array-index into private pointer array on success.
 * \retval -1 on error.
 */
static int pri_find_principle(struct sig_pri_span *pri, int channel, q931_call *call)
{
   int x;
   int span;
   int principle;
   int prioffset;

   if (channel < 0) {
      /* Channel is not picked yet. */
      return -1;
   }

   prioffset = PRI_CHANNEL(channel);
   if (!prioffset || (channel & PRI_HELD_CALL)) {
      /* Find the call waiting call or held call. */
      return pri_find_principle_by_call(pri, call);
   }

   span = PRI_SPAN(channel);
   if (!(channel & PRI_EXPLICIT)) {
      int index;

      index = pri_active_dchan_index(pri);
      if (index == -1) {
         return -1;
      }
      span = pri->dchan_logical_span[index];
   }

   principle = -1;
   for (x = 0; x < pri->numchans; x++) {
      if (pri->pvts[x]
         && pri->pvts[x]->prioffset == prioffset
         && pri->pvts[x]->logicalspan == span
         && !pri->pvts[x]->no_b_channel) {
         principle = x;
         break;
      }
   }

   return principle;
}

/*!
 * \internal
 * \brief Fixup the private structure associated with the libpri call.
 *
 * \param pri PRI span control structure.
 * \param principle Array-index into private array to move call to if not already there.
 * \param call LibPRI opaque call pointer to find if need to move call.
 *
 * \note Assumes the pri->lock is already obtained.
 *
 * \retval principle on success.
 * \retval -1 on error.
 */
static int pri_fixup_principle(struct sig_pri_span *pri, int principle, q931_call *call)
{
   int x;

   if (principle < 0 || pri->numchans <= principle) {
      /* Out of rannge */
      return -1;
   }
   if (!call) {
      /* No call */
      return principle;
   }
   if (pri->pvts[principle] && pri->pvts[principle]->call == call) {
      /* Call is already on the specified principle. */
      return principle;
   }

   /* Find the old principle location. */
   for (x = 0; x < pri->numchans; x++) {
      struct sig_pri_chan *new_chan;
      struct sig_pri_chan *old_chan;

      if (!pri->pvts[x] || pri->pvts[x]->call != call) {
         continue;
      }

      /* Found our call */
      new_chan = pri->pvts[principle];
      old_chan = pri->pvts[x];

      /* Get locks to safely move to the new private structure. */
      sig_pri_lock_private(old_chan);
      sig_pri_lock_owner(pri, x);
      sig_pri_lock_private(new_chan);

      ast_verb(3, "Moving call (%s) from channel %d to %d.\n",
         old_chan->owner ? ast_channel_name(old_chan->owner) : "",
         old_chan->channel, new_chan->channel);
      if (!sig_pri_is_chan_available(new_chan)) {
         ast_log(LOG_WARNING,
            "Can't move call (%s) from channel %d to %d.  It is already in use.\n",
            old_chan->owner ? ast_channel_name(old_chan->owner) : "",
            old_chan->channel, new_chan->channel);
         sig_pri_unlock_private(new_chan);
         if (old_chan->owner) {
            ast_channel_unlock(old_chan->owner);
         }
         sig_pri_unlock_private(old_chan);
         return -1;
      }

      sig_pri_fixup_chans(old_chan, new_chan);

      /* Fix it all up now */
      new_chan->owner = old_chan->owner;
      old_chan->owner = NULL;

      new_chan->call = old_chan->call;
      old_chan->call = NULL;

      /* Transfer flags from the old channel. */
#if defined(HAVE_PRI_AOC_EVENTS)
      new_chan->aoc_s_request_invoke_id_valid = old_chan->aoc_s_request_invoke_id_valid;
      new_chan->waiting_for_aoce = old_chan->waiting_for_aoce;
      new_chan->holding_aoce = old_chan->holding_aoce;
#endif   /* defined(HAVE_PRI_AOC_EVENTS) */
      new_chan->alreadyhungup = old_chan->alreadyhungup;
      new_chan->isidlecall = old_chan->isidlecall;
      new_chan->progress = old_chan->progress;
      new_chan->allocated = old_chan->allocated;
      new_chan->outgoing = old_chan->outgoing;
      new_chan->digital = old_chan->digital;
#if defined(HAVE_PRI_CALL_WAITING)
      new_chan->is_call_waiting = old_chan->is_call_waiting;
#endif   /* defined(HAVE_PRI_CALL_WAITING) */

#if defined(HAVE_PRI_AOC_EVENTS)
      old_chan->aoc_s_request_invoke_id_valid = 0;
      old_chan->waiting_for_aoce = 0;
      old_chan->holding_aoce = 0;
#endif   /* defined(HAVE_PRI_AOC_EVENTS) */
      old_chan->alreadyhungup = 0;
      old_chan->isidlecall = 0;
      old_chan->progress = 0;
      old_chan->allocated = 0;
      old_chan->outgoing = 0;
      old_chan->digital = 0;
#if defined(HAVE_PRI_CALL_WAITING)
      old_chan->is_call_waiting = 0;
#endif   /* defined(HAVE_PRI_CALL_WAITING) */

      /* More stuff to transfer to the new channel. */
      new_chan->call_level = old_chan->call_level;
      old_chan->call_level = SIG_PRI_CALL_LEVEL_IDLE;
#if defined(HAVE_PRI_REVERSE_CHARGE)
      new_chan->reverse_charging_indication = old_chan->reverse_charging_indication;
#endif   /* defined(HAVE_PRI_REVERSE_CHARGE) */
#if defined(HAVE_PRI_SETUP_KEYPAD)
      strcpy(new_chan->keypad_digits, old_chan->keypad_digits);
#endif   /* defined(HAVE_PRI_SETUP_KEYPAD) */
      strcpy(new_chan->deferred_digits, old_chan->deferred_digits);
      strcpy(new_chan->moh_suggested, old_chan->moh_suggested);
      new_chan->moh_state = old_chan->moh_state;
      old_chan->moh_state = SIG_PRI_MOH_STATE_IDLE;

#if defined(HAVE_PRI_AOC_EVENTS)
      new_chan->aoc_s_request_invoke_id = old_chan->aoc_s_request_invoke_id;
      new_chan->aoc_e = old_chan->aoc_e;
#endif   /* defined(HAVE_PRI_AOC_EVENTS) */
      strcpy(new_chan->user_tag, old_chan->user_tag);

      if (new_chan->no_b_channel) {
         /* Copy the real channel configuration to the no B channel interface. */
         new_chan->hidecallerid = old_chan->hidecallerid;
         new_chan->hidecalleridname = old_chan->hidecalleridname;
         new_chan->immediate = old_chan->immediate;
         new_chan->priexclusive = old_chan->priexclusive;
         new_chan->priindication_oob = old_chan->priindication_oob;
         new_chan->use_callerid = old_chan->use_callerid;
         new_chan->use_callingpres = old_chan->use_callingpres;
         new_chan->stripmsd = old_chan->stripmsd;
         strcpy(new_chan->context, old_chan->context);
         strcpy(new_chan->mohinterpret, old_chan->mohinterpret);

         /* Become a member of the old channel span/trunk-group. */
         new_chan->logicalspan = old_chan->logicalspan;
         new_chan->mastertrunkgroup = old_chan->mastertrunkgroup;
      } else if (old_chan->no_b_channel) {
         /*
          * We are transitioning from a held/call-waiting channel to a
          * real channel so we need to make sure that the media path is
          * open.  (Needed especially if the channel is natively
          * bridged.)
          */
         sig_pri_open_media(new_chan);
      }

      if (new_chan->owner) {
         sig_pri_ami_channel_event(new_chan);
      }

      sig_pri_unlock_private(old_chan);
      if (new_chan->owner) {
         ast_channel_unlock(new_chan->owner);
      }
      sig_pri_unlock_private(new_chan);

      return principle;
   }
   ast_verb(3, "Call specified, but not found.\n");
   return -1;
}

/*!
 * \internal
 * \brief Find and fixup the private structure associated with the libpri call.
 *
 * \param pri PRI span control structure.
 * \param channel LibPRI encoded channel ID.
 * \param call LibPRI opaque call pointer.
 *
 * \details
 * This is a combination of pri_find_principle() and pri_fixup_principle()
 * to reduce code redundancy and to make handling several PRI_EVENT_xxx's
 * consistent for the current architecture.
 *
 * \note Assumes the pri->lock is already obtained.
 *
 * \retval array-index into private pointer array on success.
 * \retval -1 on error.
 */
static int pri_find_fixup_principle(struct sig_pri_span *pri, int channel, q931_call *call)
{
   int chanpos;

   chanpos = pri_find_principle(pri, channel, call);
   if (chanpos < 0) {
      ast_log(LOG_WARNING, "Span %d: PRI requested channel %d/%d is unconfigured.\n",
         pri->span, PRI_SPAN(channel), PRI_CHANNEL(channel));
      sig_pri_kill_call(pri, call, PRI_CAUSE_IDENTIFIED_CHANNEL_NOTEXIST);
      return -1;
   }
   chanpos = pri_fixup_principle(pri, chanpos, call);
   if (chanpos < 0) {
      ast_log(LOG_WARNING, "Span %d: PRI requested channel %d/%d is not available.\n",
         pri->span, PRI_SPAN(channel), PRI_CHANNEL(channel));
      /*
       * Using Q.931 section 5.2.3.1 b) as the reason for picking
       * PRI_CAUSE_CHANNEL_UNACCEPTABLE.  Receiving a
       * PRI_CAUSE_REQUESTED_CHAN_UNAVAIL would cause us to restart
       * that channel (which is not specified by Q.931) and kill some
       * other call which would be bad.
       */
      sig_pri_kill_call(pri, call, PRI_CAUSE_CHANNEL_UNACCEPTABLE);
      return -1;
   }
   return chanpos;
}

static char * redirectingreason2str(int redirectingreason)
{
   switch (redirectingreason) {
   case 0:
      return "UNKNOWN";
   case 1:
      return "BUSY";
   case 2:
      return "NO_REPLY";
   case 0xF:
      return "UNCONDITIONAL";
   default:
      return "NOREDIRECT";
   }
}

static char *dialplan2str(int dialplan)
{
   if (dialplan == -1) {
      return("Dynamically set dialplan in ISDN");
   }
   return (pri_plan2str(dialplan));
}

/*!
 * \internal
 * \brief Apply numbering plan prefix to the given number.
 *
 * \param buf Buffer to put number into.
 * \param size Size of given buffer.
 * \param pri PRI span control structure.
 * \param number Number to apply numbering plan.
 * \param plan Numbering plan to apply.
 *
 * \return Nothing
 */
static void apply_plan_to_number(char *buf, size_t size, const struct sig_pri_span *pri, const char *number, int plan)
{
   switch (plan) {
   case PRI_INTERNATIONAL_ISDN:     /* Q.931 dialplan == 0x11 international dialplan => prepend international prefix digits */
      snprintf(buf, size, "%s%s", pri->internationalprefix, number);
      break;
   case PRI_NATIONAL_ISDN:       /* Q.931 dialplan == 0x21 national dialplan => prepend national prefix digits */
      snprintf(buf, size, "%s%s", pri->nationalprefix, number);
      break;
   case PRI_LOCAL_ISDN:       /* Q.931 dialplan == 0x41 local dialplan => prepend local prefix digits */
      snprintf(buf, size, "%s%s", pri->localprefix, number);
      break;
   case PRI_PRIVATE:       /* Q.931 dialplan == 0x49 private dialplan => prepend private prefix digits */
      snprintf(buf, size, "%s%s", pri->privateprefix, number);
      break;
   case PRI_UNKNOWN:       /* Q.931 dialplan == 0x00 unknown dialplan => prepend unknown prefix digits */
      snprintf(buf, size, "%s%s", pri->unknownprefix, number);
      break;
   default:          /* other Q.931 dialplan => don't twiddle with callingnum */
      snprintf(buf, size, "%s", number);
      break;
   }
}

/*!
 * \internal
 * \brief Apply numbering plan prefix to the given number if the number exists.
 *
 * \param buf Buffer to put number into.
 * \param size Size of given buffer.
 * \param pri PRI span control structure.
 * \param number Number to apply numbering plan.
 * \param plan Numbering plan to apply.
 *
 * \return Nothing
 */
static void apply_plan_to_existing_number(char *buf, size_t size, const struct sig_pri_span *pri, const char *number, int plan)
{
   /* Make sure a number exists so the prefix isn't placed on an empty string. */
   if (ast_strlen_zero(number)) {
      if (size) {
         *buf = '\0';
      }
      return;
   }
   apply_plan_to_number(buf, size, pri, number, plan);
}

/*!
 * \internal
 * \brief Restart the next channel we think is idle on the span.
 *
 * \param pri PRI span control structure.
 *
 * \note Assumes the pri->lock is already obtained.
 *
 * \return Nothing
 */
static void pri_check_restart(struct sig_pri_span *pri)
{
#if defined(HAVE_PRI_SERVICE_MESSAGES)
   unsigned why;
#endif   /* defined(HAVE_PRI_SERVICE_MESSAGES) */

   for (++pri->resetpos; pri->resetpos < pri->numchans; ++pri->resetpos) {
      if (!pri->pvts[pri->resetpos]
         || pri->pvts[pri->resetpos]->no_b_channel
         || sig_pri_is_chan_in_use(pri->pvts[pri->resetpos])) {
         continue;
      }
#if defined(HAVE_PRI_SERVICE_MESSAGES)
      why = pri->pvts[pri->resetpos]->service_status;
      if (why) {
         ast_log(LOG_NOTICE,
            "Span %d: channel %d out-of-service (reason: %s), not sending RESTART\n",
            pri->span, pri->pvts[pri->resetpos]->channel,
            (why & SRVST_FAREND) ? (why & SRVST_NEAREND) ? "both ends" : "far end" : "near end");
         continue;
      }
#endif   /* defined(HAVE_PRI_SERVICE_MESSAGES) */
      break;
   }
   if (pri->resetpos < pri->numchans) {
      /* Mark the channel as resetting and restart it */
      pri->pvts[pri->resetpos]->resetting = SIG_PRI_RESET_ACTIVE;
      pri_reset(pri->pri, PVT_TO_CHANNEL(pri->pvts[pri->resetpos]));
   } else {
      pri->resetting = 0;
      time(&pri->lastreset);
      sig_pri_span_devstate_changed(pri);
   }
}

#if defined(HAVE_PRI_CALL_WAITING)
/*!
 * \internal
 * \brief Init the private channel configuration using the span controller.
 * \since 1.8
 *
 * \param pvt Channel to init the configuration.
 * \param pri PRI span control structure.
 *
 * \note Assumes the pri->lock is already obtained.
 *
 * \return Nothing
 */
static void sig_pri_init_config(struct sig_pri_chan *pvt, struct sig_pri_span *pri)
{
   pvt->stripmsd = pri->ch_cfg.stripmsd;
   pvt->hidecallerid = pri->ch_cfg.hidecallerid;
   pvt->hidecalleridname = pri->ch_cfg.hidecalleridname;
   pvt->immediate = pri->ch_cfg.immediate;
   pvt->priexclusive = pri->ch_cfg.priexclusive;
   pvt->priindication_oob = pri->ch_cfg.priindication_oob;
   pvt->use_callerid = pri->ch_cfg.use_callerid;
   pvt->use_callingpres = pri->ch_cfg.use_callingpres;
   ast_copy_string(pvt->context, pri->ch_cfg.context, sizeof(pvt->context));
   ast_copy_string(pvt->mohinterpret, pri->ch_cfg.mohinterpret, sizeof(pvt->mohinterpret));

   if (sig_pri_callbacks.init_config) {
      sig_pri_callbacks.init_config(pvt->chan_pvt, pri);
   }
}
#endif   /* defined(HAVE_PRI_CALL_WAITING) */

/*!
 * \internal
 * \brief Find an empty B-channel interface to use.
 *
 * \param pri PRI span control structure.
 * \param backwards TRUE if the search starts from higher channels.
 *
 * \note Assumes the pri->lock is already obtained.
 *
 * \retval array-index into private pointer array on success.
 * \retval -1 on error.
 */
static int pri_find_empty_chan(struct sig_pri_span *pri, int backwards)
{
   int x;
   if (backwards)
      x = pri->numchans;
   else
      x = 0;
   for (;;) {
      if (backwards && (x < 0))
         break;
      if (!backwards && (x >= pri->numchans))
         break;
      if (pri->pvts[x]
         && !pri->pvts[x]->no_b_channel
         && sig_pri_is_chan_available(pri->pvts[x])) {
         ast_debug(1, "Found empty available channel %d/%d\n",
            pri->pvts[x]->logicalspan, pri->pvts[x]->prioffset);
         return x;
      }
      if (backwards)
         x--;
      else
         x++;
   }
   return -1;
}

#if defined(HAVE_PRI_CALL_HOLD)
/*!
 * \internal
 * \brief Find or create an empty no-B-channel interface to use.
 * \since 1.8
 *
 * \param pri PRI span control structure.
 *
 * \note Assumes the pri->lock is already obtained.
 *
 * \retval array-index into private pointer array on success.
 * \retval -1 on error.
 */
static int pri_find_empty_nobch(struct sig_pri_span *pri)
{
   int idx;

   for (idx = 0; idx < pri->numchans; ++idx) {
      if (pri->pvts[idx]
         && pri->pvts[idx]->no_b_channel
         && sig_pri_is_chan_available(pri->pvts[idx])) {
         ast_debug(1, "Found empty available no B channel interface\n");
         return idx;
      }
   }

   /* Need to create a new interface. */
   if (sig_pri_callbacks.new_nobch_intf) {
      idx = sig_pri_callbacks.new_nobch_intf(pri);
   } else {
      idx = -1;
   }
   return idx;
}
#endif   /* defined(HAVE_PRI_CALL_HOLD) */

static void *do_idle_thread(void *v_pvt)
{
   struct sig_pri_chan *pvt = v_pvt;
   struct ast_channel *chan = pvt->owner;
   struct ast_frame *f;
   char ex[80];
   /* Wait up to 30 seconds for an answer */
   int timeout_ms = 30000;
   int ms;
   struct timeval start;
   struct ast_callid *callid;

   if ((callid = ast_channel_callid(chan))) {
      ast_callid_threadassoc_add(callid);
      callid = ast_callid_unref(callid);
   }

   ast_verb(3, "Initiating idle call on channel %s\n", ast_channel_name(chan));
   snprintf(ex, sizeof(ex), "%d/%s", pvt->channel, pvt->pri->idledial);
   if (ast_call(chan, ex, 0)) {
      ast_log(LOG_WARNING, "Idle dial failed on '%s' to '%s'\n", ast_channel_name(chan), ex);
      ast_hangup(chan);
      return NULL;
   }
   start = ast_tvnow();
   while ((ms = ast_remaining_ms(start, timeout_ms))) {
      if (ast_waitfor(chan, ms) <= 0) {
         break;
      }

      f = ast_read(chan);
      if (!f) {
         /* Got hangup */
         break;
      }
      if (f->frametype == AST_FRAME_CONTROL) {
         switch (f->subclass.integer) {
         case AST_CONTROL_ANSWER:
            /* Launch the PBX */
            ast_channel_exten_set(chan, pvt->pri->idleext);
            ast_channel_context_set(chan, pvt->pri->idlecontext);
            ast_channel_priority_set(chan, 1);
            ast_verb(4, "Idle channel '%s' answered, sending to %s@%s\n", ast_channel_name(chan), ast_channel_exten(chan), ast_channel_context(chan));
            ast_pbx_run(chan);
            /* It's already hungup, return immediately */
            return NULL;
         case AST_CONTROL_BUSY:
            ast_verb(4, "Idle channel '%s' busy, waiting...\n", ast_channel_name(chan));
            break;
         case AST_CONTROL_CONGESTION:
            ast_verb(4, "Idle channel '%s' congested, waiting...\n", ast_channel_name(chan));
            break;
         };
      }
      ast_frfree(f);
   }
   /* Hangup the channel since nothing happend */
   ast_hangup(chan);
   return NULL;
}

static void *pri_ss_thread(void *data)
{
   struct sig_pri_chan *p = data;
   struct ast_channel *chan = p->owner;
   char exten[AST_MAX_EXTENSION];
   int res;
   int len;
   int timeout;
   struct ast_callid *callid;

   if (!chan) {
      /* We lost the owner before we could get started. */
      return NULL;
   }

   if ((callid = ast_channel_callid(chan))) {
      ast_callid_threadassoc_add(callid);
      ast_callid_unref(callid);
   }

   /*
    * In the bizarre case where the channel has become a zombie before we
    * even get started here, abort safely.
    */
   if (!ast_channel_tech_pvt(chan)) {
      ast_log(LOG_WARNING, "Channel became a zombie before simple switch could be started (%s)\n", ast_channel_name(chan));
      ast_hangup(chan);
      return NULL;
   }

   ast_verb(3, "Starting simple switch on '%s'\n", ast_channel_name(chan));

   sig_pri_dsp_reset_and_flush_digits(p);

   /* Now loop looking for an extension */
   ast_copy_string(exten, p->exten, sizeof(exten));
   len = strlen(exten);
   res = 0;
   while ((len < AST_MAX_EXTENSION-1) && ast_matchmore_extension(chan, ast_channel_context(chan), exten, 1, p->cid_num)) {
      if (len && !ast_ignore_pattern(ast_channel_context(chan), exten))
         sig_pri_play_tone(p, -1);
      else
         sig_pri_play_tone(p, SIG_PRI_TONE_DIALTONE);
      if (ast_exists_extension(chan, ast_channel_context(chan), exten, 1, p->cid_num))
         timeout = pri_matchdigittimeout;
      else
         timeout = pri_gendigittimeout;
      res = ast_waitfordigit(chan, timeout);
      if (res < 0) {
         ast_debug(1, "waitfordigit returned < 0...\n");
         ast_hangup(chan);
         return NULL;
      } else if (res) {
         exten[len++] = res;
         exten[len] = '\0';
      } else
         break;
   }
   /* if no extension was received ('unspecified') on overlap call, use the 's' extension */
   if (ast_strlen_zero(exten)) {
      ast_verb(3, "Going to extension s|1 because of empty extension received on overlap call\n");
      exten[0] = 's';
      exten[1] = '\0';
   } else {
      ast_free(ast_channel_dialed(chan)->number.str);
      ast_channel_dialed(chan)->number.str = ast_strdup(exten);

      if (p->pri->append_msn_to_user_tag && p->pri->nodetype != PRI_NETWORK) {
         /*
          * Update the user tag for party id's from this device for this call
          * now that we have a complete MSN from the network.
          */
         snprintf(p->user_tag, sizeof(p->user_tag), "%s_%s", p->pri->initial_user_tag,
            exten);
         ast_free(ast_channel_caller(chan)->id.tag);
         ast_channel_caller(chan)->id.tag = ast_strdup(p->user_tag);
      }
   }
   sig_pri_play_tone(p, -1);
   if (ast_exists_extension(chan, ast_channel_context(chan), exten, 1, p->cid_num)) {
      /* Start the real PBX */
      ast_channel_exten_set(chan, exten);
      sig_pri_dsp_reset_and_flush_digits(p);
#if defined(ISSUE_16789)
      /*
       * Conditionaled out this code to effectively revert the Mantis
       * issue 16789 change.  It breaks overlap dialing through
       * Asterisk.  There is not enough information available at this
       * point to know if dialing is complete.  The
       * ast_exists_extension(), ast_matchmore_extension(), and
       * ast_canmatch_extension() calls are not adequate to detect a
       * dial through extension pattern of "_9!".
       *
       * Workaround is to use the dialplan Proceeding() application
       * early on non-dial through extensions.
       */
      if ((p->pri->overlapdial & DAHDI_OVERLAPDIAL_INCOMING)
         && !ast_matchmore_extension(chan, ast_channel_context(chan), exten, 1, p->cid_num)) {
         sig_pri_lock_private(p);
         if (p->pri->pri) {
            pri_grab(p, p->pri);
            if (p->call_level < SIG_PRI_CALL_LEVEL_PROCEEDING) {
               p->call_level = SIG_PRI_CALL_LEVEL_PROCEEDING;
            }
            pri_proceeding(p->pri->pri, p->call, PVT_TO_CHANNEL(p), 0);
            pri_rel(p->pri);
         }
         sig_pri_unlock_private(p);
      }
#endif   /* defined(ISSUE_16789) */

      sig_pri_set_echocanceller(p, 1);
      ast_setstate(chan, AST_STATE_RING);
      res = ast_pbx_run(chan);
      if (res) {
         ast_log(LOG_WARNING, "PBX exited non-zero!\n");
      }
   } else {
      ast_debug(1, "No such possible extension '%s' in context '%s'\n", exten, ast_channel_context(chan));
      ast_channel_hangupcause_set(chan, AST_CAUSE_UNALLOCATED);
      ast_hangup(chan);
      p->exten[0] = '\0';
      /* Since we send release complete here, we won't get one */
      p->call = NULL;
      ast_mutex_lock(&p->pri->lock);
      sig_pri_span_devstate_changed(p->pri);
      ast_mutex_unlock(&p->pri->lock);
   }
   return NULL;
}

void pri_event_alarm(struct sig_pri_span *pri, int index, int before_start_pri)
{
   pri->dchanavail[index] &= ~(DCHAN_NOTINALARM | DCHAN_UP);
   if (!before_start_pri) {
      pri_find_dchan(pri);
   }
}

void pri_event_noalarm(struct sig_pri_span *pri, int index, int before_start_pri)
{
   pri->dchanavail[index] |= DCHAN_NOTINALARM;
   if (!before_start_pri)
      pri_restart(pri->dchans[index]);
}

/*!
 * \internal
 * \brief Convert libpri party name into asterisk party name.
 * \since 1.8
 *
 * \param ast_name Asterisk party name structure to fill.  Must already be set initialized.
 * \param pri_name libpri party name structure containing source information.
 *
 * \note The filled in ast_name structure needs to be destroyed by
 * ast_party_name_free() when it is no longer needed.
 *
 * \return Nothing
 */
static void sig_pri_party_name_convert(struct ast_party_name *ast_name, const struct pri_party_name *pri_name)
{
   ast_name->str = ast_strdup(pri_name->str);
   ast_name->char_set = pri_to_ast_char_set(pri_name->char_set);
   ast_name->presentation = pri_to_ast_presentation(pri_name->presentation);
   ast_name->valid = 1;
}

/*!
 * \internal
 * \brief Convert libpri party number into asterisk party number.
 * \since 1.8
 *
 * \param ast_number Asterisk party number structure to fill.  Must already be set initialized.
 * \param pri_number libpri party number structure containing source information.
 * \param pri PRI span control structure.
 *
 * \note The filled in ast_number structure needs to be destroyed by
 * ast_party_number_free() when it is no longer needed.
 *
 * \return Nothing
 */
static void sig_pri_party_number_convert(struct ast_party_number *ast_number, const struct pri_party_number *pri_number, struct sig_pri_span *pri)
{
   char number[AST_MAX_EXTENSION];

   apply_plan_to_existing_number(number, sizeof(number), pri, pri_number->str,
      pri_number->plan);
   ast_number->str = ast_strdup(number);
   ast_number->plan = pri_number->plan;
   ast_number->presentation = pri_to_ast_presentation(pri_number->presentation);
   ast_number->valid = 1;
}

/*!
 * \internal
 * \brief Convert libpri party id into asterisk party id.
 * \since 1.8
 *
 * \param ast_id Asterisk party id structure to fill.  Must already be set initialized.
 * \param pri_id libpri party id structure containing source information.
 * \param pri PRI span control structure.
 *
 * \note The filled in ast_id structure needs to be destroyed by
 * ast_party_id_free() when it is no longer needed.
 *
 * \return Nothing
 */
static void sig_pri_party_id_convert(struct ast_party_id *ast_id, const struct pri_party_id *pri_id, struct sig_pri_span *pri)
{
   if (pri_id->name.valid) {
      sig_pri_party_name_convert(&ast_id->name, &pri_id->name);
   }
   if (pri_id->number.valid) {
      sig_pri_party_number_convert(&ast_id->number, &pri_id->number, pri);
   }
#if defined(HAVE_PRI_SUBADDR)
   if (pri_id->subaddress.valid) {
      sig_pri_set_subaddress(&ast_id->subaddress, &pri_id->subaddress);
   }
#endif   /* defined(HAVE_PRI_SUBADDR) */
}

/*!
 * \internal
 * \brief Convert libpri redirecting information into asterisk redirecting information.
 * \since 1.8
 *
 * \param ast_redirecting Asterisk redirecting structure to fill.
 * \param pri_redirecting libpri redirecting structure containing source information.
 * \param ast_guide Asterisk redirecting structure to use as an initialization guide.
 * \param pri PRI span control structure.
 *
 * \note The filled in ast_redirecting structure needs to be destroyed by
 * ast_party_redirecting_free() when it is no longer needed.
 *
 * \return Nothing
 */
static void sig_pri_redirecting_convert(struct ast_party_redirecting *ast_redirecting,
   const struct pri_party_redirecting *pri_redirecting,
   const struct ast_party_redirecting *ast_guide,
   struct sig_pri_span *pri)
{
   ast_party_redirecting_set_init(ast_redirecting, ast_guide);

   sig_pri_party_id_convert(&ast_redirecting->orig, &pri_redirecting->orig_called, pri);
   sig_pri_party_id_convert(&ast_redirecting->from, &pri_redirecting->from, pri);
   sig_pri_party_id_convert(&ast_redirecting->to, &pri_redirecting->to, pri);
   ast_redirecting->count = pri_redirecting->count;
   ast_redirecting->reason = pri_to_ast_reason(pri_redirecting->reason);
   ast_redirecting->orig_reason = pri_to_ast_reason(pri_redirecting->orig_reason);
}

/*!
 * \internal
 * \brief Determine if the given extension matches one of the MSNs in the pattern list.
 * \since 1.8
 *
 * \param msn_patterns Comma separated list of MSN patterns to match.
 * \param exten Extension to match in the MSN list.
 *
 * \retval 1 if matches.
 * \retval 0 if no match.
 */
static int sig_pri_msn_match(const char *msn_patterns, const char *exten)
{
   char *pattern;
   char *msn_list;
   char *list_tail;

   msn_list = ast_strdupa(msn_patterns);

   list_tail = NULL;
   pattern = strtok_r(msn_list, ",", &list_tail);
   while (pattern) {
      pattern = ast_strip(pattern);
      if (!ast_strlen_zero(pattern) && ast_extension_match(pattern, exten)) {
         /* Extension matched the pattern. */
         return 1;
      }
      pattern = strtok_r(NULL, ",", &list_tail);
   }
   /* Did not match any pattern in the list. */
   return 0;
}

#if defined(HAVE_PRI_MCID)
/*!
 * \internal
 * \brief Append the given party id to the event string.
 * \since 1.8
 *
 * \param msg Event message string being built.
 * \param prefix Prefix to add to the party id lines.
 * \param party Party information to encode.
 *
 * \return Nothing
 */
static void sig_pri_event_party_id(struct ast_str **msg, const char *prefix, struct ast_party_id *party)
{
   int pres;

   /* Combined party presentation */
   pres = ast_party_id_presentation(party);
   ast_str_append(msg, 0, "%sPres: %d (%s)\r\n", prefix, pres,
      ast_describe_caller_presentation(pres));

   /* Party number */
   ast_str_append(msg, 0, "%sNumValid: %d\r\n", prefix,
      (unsigned) party->number.valid);
   ast_str_append(msg, 0, "%sNum: %s\r\n", prefix,
      S_COR(party->number.valid, party->number.str, ""));
   ast_str_append(msg, 0, "%ston: %d\r\n", prefix, party->number.plan);
   if (party->number.valid) {
      ast_str_append(msg, 0, "%sNumPlan: %d\r\n", prefix, party->number.plan);
      ast_str_append(msg, 0, "%sNumPres: %d (%s)\r\n", prefix,
         party->number.presentation,
         ast_describe_caller_presentation(party->number.presentation));
   }

   /* Party name */
   ast_str_append(msg, 0, "%sNameValid: %d\r\n", prefix,
      (unsigned) party->name.valid);
   ast_str_append(msg, 0, "%sName: %s\r\n", prefix,
      S_COR(party->name.valid, party->name.str, ""));
   if (party->name.valid) {
      ast_str_append(msg, 0, "%sNameCharSet: %s\r\n", prefix,
         ast_party_name_charset_describe(party->name.char_set));
      ast_str_append(msg, 0, "%sNamePres: %d (%s)\r\n", prefix,
         party->name.presentation,
         ast_describe_caller_presentation(party->name.presentation));
   }

#if defined(HAVE_PRI_SUBADDR)
   /* Party subaddress */
   if (party->subaddress.valid) {
      static const char subaddress[] = "Subaddr";

      ast_str_append(msg, 0, "%s%s: %s\r\n", prefix, subaddress,
         S_OR(party->subaddress.str, ""));
      ast_str_append(msg, 0, "%s%sType: %d\r\n", prefix, subaddress,
         party->subaddress.type);
      ast_str_append(msg, 0, "%s%sOdd: %d\r\n", prefix, subaddress,
         party->subaddress.odd_even_indicator);
   }
#endif   /* defined(HAVE_PRI_SUBADDR) */
}
#endif   /* defined(HAVE_PRI_MCID) */

#if defined(HAVE_PRI_MCID)
/*!
 * \internal
 * \brief Handle the MCID event.
 * \since 1.8
 *
 * \param pri PRI span control structure.
 * \param mcid MCID event parameters.
 * \param owner Asterisk channel associated with the call.
 * NULL if Asterisk no longer has the ast_channel struct.
 *
 * \note Assumes the pri->lock is already obtained.
 * \note Assumes the owner channel lock is already obtained if still present.
 *
 * \return Nothing
 */
static void sig_pri_mcid_event(struct sig_pri_span *pri, const struct pri_subcmd_mcid_req *mcid, struct ast_channel *owner)
{
   struct ast_channel *chans[1];
   struct ast_str *msg;
   struct ast_party_id party;

   msg = ast_str_create(4096);
   if (!msg) {
      return;
   }

   if (owner) {
      /*
       * The owner channel is present.
       * Pass the event to the peer as well.
       */
      ast_queue_control(owner, AST_CONTROL_MCID);

      ast_str_append(&msg, 0, "Channel: %s\r\n", ast_channel_name(owner));
      ast_str_append(&msg, 0, "UniqueID: %s\r\n", ast_channel_uniqueid(owner));

      sig_pri_event_party_id(&msg, "CallerID", &ast_channel_connected(owner)->id);
   } else {
      /*
       * Since we no longer have an owner channel,
       * we have to use the caller information supplied by libpri.
       */
      ast_party_id_init(&party);
      sig_pri_party_id_convert(&party, &mcid->originator, pri);
      sig_pri_event_party_id(&msg, "CallerID", &party);
      ast_party_id_free(&party);
   }

   /* Always use libpri's called party information. */
   ast_party_id_init(&party);
   sig_pri_party_id_convert(&party, &mcid->answerer, pri);
   sig_pri_event_party_id(&msg, "ConnectedID", &party);
   ast_party_id_free(&party);

   chans[0] = owner;
   ast_manager_event_multichan(EVENT_FLAG_CALL, "MCID", owner ? 1 : 0, chans, "%s",
      ast_str_buffer(msg));
   ast_free(msg);
}
#endif   /* defined(HAVE_PRI_MCID) */

#if defined(HAVE_PRI_TRANSFER)
struct xfer_rsp_data {
   struct sig_pri_span *pri;
   /*! Call to send transfer success/fail response over. */
   q931_call *call;
   /*! Invocation ID to use when sending a reply to the transfer request. */
   int invoke_id;
};
#endif   /* defined(HAVE_PRI_TRANSFER) */

#if defined(HAVE_PRI_TRANSFER)
/*!
 * \internal
 * \brief Send the transfer success/fail response message.
 * \since 1.8
 *
 * \param data Callback user data pointer
 * \param is_successful TRUE if the transfer was successful.
 *
 * \return Nothing
 */
static void sig_pri_transfer_rsp(void *data, int is_successful)
{
   struct xfer_rsp_data *rsp = data;

   pri_transfer_rsp(rsp->pri->pri, rsp->call, rsp->invoke_id, is_successful);
}
#endif   /* defined(HAVE_PRI_TRANSFER) */

#if defined(HAVE_PRI_CALL_HOLD) || defined(HAVE_PRI_TRANSFER)
/*!
 * \brief Protocol callback to indicate if transfer will happen.
 * \since 1.8
 *
 * \param data Callback user data pointer
 * \param is_successful TRUE if the transfer will happen.
 *
 * \return Nothing
 */
typedef void (*xfer_rsp_callback)(void *data, int is_successful);
#endif   /* defined(HAVE_PRI_CALL_HOLD) || defined(HAVE_PRI_TRANSFER) */

#if defined(HAVE_PRI_CALL_HOLD) || defined(HAVE_PRI_TRANSFER)
/*!
 * \internal
 * \brief Attempt to transfer the two calls to each other.
 * \since 1.8
 *
 * \param pri PRI span control structure.
 * \param call_1_pri First call involved in the transfer. (transferee; usually on hold)
 * \param call_1_held TRUE if call_1_pri is on hold.
 * \param call_2_pri Second call involved in the transfer. (target; usually active/ringing)
 * \param call_2_held TRUE if call_2_pri is on hold.
 * \param rsp_callback Protocol callback to indicate if transfer will happen. NULL if not used.
 * \param data Callback user data pointer
 *
 * \note Assumes the pri->lock is already obtained.
 *
 * \retval 0 on success.
 * \retval -1 on error.
 */
static int sig_pri_attempt_transfer(struct sig_pri_span *pri, q931_call *call_1_pri, int call_1_held, q931_call *call_2_pri, int call_2_held, xfer_rsp_callback rsp_callback, void *data)
{
   struct attempt_xfer_call {
      q931_call *pri;
      struct ast_channel *ast;
      int held;
      int chanpos;
   };
   int retval;
   struct ast_channel *transferee;
   struct attempt_xfer_call *call_1;
   struct attempt_xfer_call *call_2;
   struct attempt_xfer_call *swap_call;
   struct attempt_xfer_call c1;
   struct attempt_xfer_call c2;

   c1.pri = call_1_pri;
   c1.held = call_1_held;
   call_1 = &c1;

   c2.pri = call_2_pri;
   c2.held = call_2_held;
   call_2 = &c2;

   call_1->chanpos = pri_find_principle_by_call(pri, call_1->pri);
   call_2->chanpos = pri_find_principle_by_call(pri, call_2->pri);
   if (call_1->chanpos < 0 || call_2->chanpos < 0) {
      /* Calls not found in span control. */
      if (rsp_callback) {
         /* Transfer failed. */
         rsp_callback(data, 0);
      }
      return -1;
   }

   /* Attempt to make transferee and target consistent. */
   if (!call_1->held && call_2->held) {
      /*
       * Swap call_1 and call_2 to make call_1 the transferee(held call)
       * and call_2 the target(active call).
       */
      swap_call = call_1;
      call_1 = call_2;
      call_2 = swap_call;
   }

   /* Deadlock avoidance is attempted. */
   sig_pri_lock_private(pri->pvts[call_1->chanpos]);
   sig_pri_lock_owner(pri, call_1->chanpos);
   sig_pri_lock_private(pri->pvts[call_2->chanpos]);
   sig_pri_lock_owner(pri, call_2->chanpos);

   call_1->ast = pri->pvts[call_1->chanpos]->owner;
   call_2->ast = pri->pvts[call_2->chanpos]->owner;
   if (!call_1->ast || !call_2->ast) {
      /* At least one owner is not present. */
      if (call_1->ast) {
         ast_channel_unlock(call_1->ast);
      }
      if (call_2->ast) {
         ast_channel_unlock(call_2->ast);
      }
      sig_pri_unlock_private(pri->pvts[call_1->chanpos]);
      sig_pri_unlock_private(pri->pvts[call_2->chanpos]);
      if (rsp_callback) {
         /* Transfer failed. */
         rsp_callback(data, 0);
      }
      return -1;
   }

   for (;;) {
      transferee = ast_bridged_channel(call_1->ast);
      if (transferee) {
         break;
      }

      /* Try masquerading the other way. */
      swap_call = call_1;
      call_1 = call_2;
      call_2 = swap_call;

      transferee = ast_bridged_channel(call_1->ast);
      if (transferee) {
         break;
      }

      /* Could not transfer.  Neither call is bridged. */
      ast_channel_unlock(call_1->ast);
      ast_channel_unlock(call_2->ast);
      sig_pri_unlock_private(pri->pvts[call_1->chanpos]);
      sig_pri_unlock_private(pri->pvts[call_2->chanpos]);

      if (rsp_callback) {
         /* Transfer failed. */
         rsp_callback(data, 0);
      }
      return -1;
   }

   ast_verb(3, "TRANSFERRING %s to %s\n", ast_channel_name(call_1->ast), ast_channel_name(call_2->ast));

   /*
    * Setup transfer masquerade.
    *
    * Note:  There is an extremely nasty deadlock avoidance issue
    * with ast_channel_transfer_masquerade().  Deadlock may be possible if
    * the channels involved are proxies (chan_agent channels) and
    * it is called with locks.  Unfortunately, there is no simple
    * or even merely difficult way to guarantee deadlock avoidance
    * and still be able to send an ECT success response without the
    * possibility of the bridged channel hanging up on us.
    */
   ast_mutex_unlock(&pri->lock);
   retval = ast_channel_transfer_masquerade(
      call_2->ast,
      ast_channel_connected(call_2->ast),
      call_2->held,
      transferee,
      ast_channel_connected(call_1->ast),
      call_1->held);

   /* Reacquire the pri->lock to hold off completion of the transfer masquerade. */
   ast_mutex_lock(&pri->lock);

   ast_channel_unlock(call_1->ast);
   ast_channel_unlock(call_2->ast);
   sig_pri_unlock_private(pri->pvts[call_1->chanpos]);
   sig_pri_unlock_private(pri->pvts[call_2->chanpos]);

   if (rsp_callback) {
      /*
       * Report transfer status.
       *
       * Must do the callback before the masquerade completes to ensure
       * that the protocol message goes out before the call leg is
       * disconnected.
       */
      rsp_callback(data, retval ? 0 : 1);
   }
   return retval;
}
#endif   /* defined(HAVE_PRI_CALL_HOLD) || defined(HAVE_PRI_TRANSFER) */

#if defined(HAVE_PRI_CCSS)
/*!
 * \internal
 * \brief Compare the CC agent private data by libpri cc_id.
 * \since 1.8
 *
 * \param obj pointer to the (user-defined part) of an object.
 * \param arg callback argument from ao2_callback()
 * \param flags flags from ao2_callback()
 *
 * \return values are a combination of enum _cb_results.
 */
static int sig_pri_cc_agent_cmp_cc_id(void *obj, void *arg, int flags)
{
   struct ast_cc_agent *agent_1 = obj;
   struct sig_pri_cc_agent_prv *agent_prv_1 = agent_1->private_data;
   struct sig_pri_cc_agent_prv *agent_prv_2 = arg;

   return (agent_prv_1 && agent_prv_1->pri == agent_prv_2->pri
      && agent_prv_1->cc_id == agent_prv_2->cc_id) ? CMP_MATCH | CMP_STOP : 0;
}
#endif   /* defined(HAVE_PRI_CCSS) */

#if defined(HAVE_PRI_CCSS)
/*!
 * \internal
 * \brief Find the CC agent by libpri cc_id.
 * \since 1.8
 *
 * \param pri PRI span control structure.
 * \param cc_id CC record ID to find.
 *
 * \note
 * Since agents are refcounted, and this function returns
 * a reference to the agent, it is imperative that you decrement
 * the refcount of the agent once you have finished using it.
 *
 * \retval agent on success.
 * \retval NULL not found.
 */
static struct ast_cc_agent *sig_pri_find_cc_agent_by_cc_id(struct sig_pri_span *pri, long cc_id)
{
   struct sig_pri_cc_agent_prv finder = {
      .pri = pri,
      .cc_id = cc_id,
   };

   return ast_cc_agent_callback(0, sig_pri_cc_agent_cmp_cc_id, &finder,
      sig_pri_cc_type_name);
}
#endif   /* defined(HAVE_PRI_CCSS) */

#if defined(HAVE_PRI_CCSS)
/*!
 * \internal
 * \brief Compare the CC monitor instance by libpri cc_id.
 * \since 1.8
 *
 * \param obj pointer to the (user-defined part) of an object.
 * \param arg callback argument from ao2_callback()
 * \param flags flags from ao2_callback()
 *
 * \return values are a combination of enum _cb_results.
 */
static int sig_pri_cc_monitor_cmp_cc_id(void *obj, void *arg, int flags)
{
   struct sig_pri_cc_monitor_instance *monitor_1 = obj;
   struct sig_pri_cc_monitor_instance *monitor_2 = arg;

   return (monitor_1->pri == monitor_2->pri
      && monitor_1->cc_id == monitor_2->cc_id) ? CMP_MATCH | CMP_STOP : 0;
}
#endif   /* defined(HAVE_PRI_CCSS) */

#if defined(HAVE_PRI_CCSS)
/*!
 * \internal
 * \brief Find the CC monitor instance by libpri cc_id.
 * \since 1.8
 *
 * \param pri PRI span control structure.
 * \param cc_id CC record ID to find.
 *
 * \note
 * Since monitor_instances are refcounted, and this function returns
 * a reference to the instance, it is imperative that you decrement
 * the refcount of the instance once you have finished using it.
 *
 * \retval monitor_instance on success.
 * \retval NULL not found.
 */
static struct sig_pri_cc_monitor_instance *sig_pri_find_cc_monitor_by_cc_id(struct sig_pri_span *pri, long cc_id)
{
   struct sig_pri_cc_monitor_instance finder = {
      .pri = pri,
      .cc_id = cc_id,
   };

   return ao2_callback(sig_pri_cc_monitors, 0, sig_pri_cc_monitor_cmp_cc_id, &finder);
}
#endif   /* defined(HAVE_PRI_CCSS) */

#if defined(HAVE_PRI_CCSS)
/*!
 * \internal
 * \brief Destroy the given monitor instance.
 * \since 1.8
 *
 * \param data Monitor instance to destroy.
 *
 * \return Nothing
 */
static void sig_pri_cc_monitor_instance_destroy(void *data)
{
   struct sig_pri_cc_monitor_instance *monitor_instance = data;

   if (monitor_instance->cc_id != -1) {
      ast_mutex_lock(&monitor_instance->pri->lock);
      pri_cc_cancel(monitor_instance->pri->pri, monitor_instance->cc_id);
      ast_mutex_unlock(&monitor_instance->pri->lock);
   }
   sig_pri_callbacks.module_unref();
}
#endif   /* defined(HAVE_PRI_CCSS) */

#if defined(HAVE_PRI_CCSS)
/*!
 * \internal
 * \brief Construct a new monitor instance.
 * \since 1.8
 *
 * \param core_id CC core ID.
 * \param pri PRI span control structure.
 * \param cc_id CC record ID.
 * \param device_name Name of device (Asterisk channel name less sequence number).
 *
 * \note
 * Since monitor_instances are refcounted, and this function returns
 * a reference to the instance, it is imperative that you decrement
 * the refcount of the instance once you have finished using it.
 *
 * \retval monitor_instance on success.
 * \retval NULL on error.
 */
static struct sig_pri_cc_monitor_instance *sig_pri_cc_monitor_instance_init(int core_id, struct sig_pri_span *pri, long cc_id, const char *device_name)
{
   struct sig_pri_cc_monitor_instance *monitor_instance;

   if (!sig_pri_callbacks.module_ref || !sig_pri_callbacks.module_unref) {
      return NULL;
   }

   monitor_instance = ao2_alloc(sizeof(*monitor_instance) + strlen(device_name),
      sig_pri_cc_monitor_instance_destroy);
   if (!monitor_instance) {
      return NULL;
   }

   monitor_instance->cc_id = cc_id;
   monitor_instance->pri = pri;
   monitor_instance->core_id = core_id;
   strcpy(monitor_instance->name, device_name);

   sig_pri_callbacks.module_ref();

   ao2_link(sig_pri_cc_monitors, monitor_instance);
   return monitor_instance;
}
#endif   /* defined(HAVE_PRI_CCSS) */

#if defined(HAVE_PRI_CCSS)
/*!
 * \internal
 * \brief Announce to the CC core that protocol CC monitor is available for this call.
 * \since 1.8
 *
 * \param pri PRI span control structure.
 * \param chanpos Channel position in the span.
 * \param cc_id CC record ID.
 * \param service CCBS/CCNR indication.
 *
 * \note Assumes the pri->lock is already obtained.
 * \note Assumes the sig_pri_lock_private(pri->pvts[chanpos]) is already obtained.
 * \note Assumes the sig_pri_lock_owner(pri, chanpos) is already obtained.
 *
 * \retval 0 on success.
 * \retval -1 on error.
 */
static int sig_pri_cc_available(struct sig_pri_span *pri, int chanpos, long cc_id, enum ast_cc_service_type service)
{
   struct sig_pri_chan *pvt;
   struct ast_cc_config_params *cc_params;
   struct sig_pri_cc_monitor_instance *monitor;
   enum ast_cc_monitor_policies monitor_policy;
   int core_id;
   int res;
   char device_name[AST_CHANNEL_NAME];
   char dialstring[AST_CHANNEL_NAME];

   pvt = pri->pvts[chanpos];

   core_id = ast_cc_get_current_core_id(pvt->owner);
   if (core_id == -1) {
      return -1;
   }

   cc_params = ast_channel_get_cc_config_params(pvt->owner);
   if (!cc_params) {
      return -1;
   }

   res = -1;
   monitor_policy = ast_get_cc_monitor_policy(cc_params);
   switch (monitor_policy) {
   case AST_CC_MONITOR_NEVER:
      /* CCSS is not enabled. */
      break;
   case AST_CC_MONITOR_NATIVE:
   case AST_CC_MONITOR_ALWAYS:
      /*
       * If it is AST_CC_MONITOR_ALWAYS and native fails we will attempt the fallback
       * later in the call to sig_pri_cc_generic_check().
       */
      ast_channel_get_device_name(pvt->owner, device_name, sizeof(device_name));
      sig_pri_make_cc_dialstring(pvt, dialstring, sizeof(dialstring));
      monitor = sig_pri_cc_monitor_instance_init(core_id, pri, cc_id, device_name);
      if (!monitor) {
         break;
      }
      res = ast_queue_cc_frame(pvt->owner, sig_pri_cc_type_name, dialstring, service,
         monitor);
      if (res) {
         monitor->cc_id = -1;
         ao2_unlink(sig_pri_cc_monitors, monitor);
         ao2_ref(monitor, -1);
      }
      break;
   case AST_CC_MONITOR_GENERIC:
      ast_queue_cc_frame(pvt->owner, AST_CC_GENERIC_MONITOR_TYPE,
         sig_pri_get_orig_dialstring(pvt), service, NULL);
      /* Say it failed to force caller to cancel native CC. */
      break;
   }
   return res;
}
#endif   /* defined(HAVE_PRI_CCSS) */

/*!
 * \internal
 * \brief Check if generic CC monitor is needed and request it.
 * \since 1.8
 *
 * \param pri PRI span control structure.
 * \param chanpos Channel position in the span.
 * \param service CCBS/CCNR indication.
 *
 * \note Assumes the pri->lock is already obtained.
 * \note Assumes the sig_pri_lock_private(pri->pvts[chanpos]) is already obtained.
 *
 * \return Nothing
 */
static void sig_pri_cc_generic_check(struct sig_pri_span *pri, int chanpos, enum ast_cc_service_type service)
{
   struct ast_channel *owner;
   struct ast_cc_config_params *cc_params;
#if defined(HAVE_PRI_CCSS)
   struct ast_cc_monitor *monitor;
   char device_name[AST_CHANNEL_NAME];
#endif   /* defined(HAVE_PRI_CCSS) */
   enum ast_cc_monitor_policies monitor_policy;
   int core_id;

   if (!pri->pvts[chanpos]->outgoing) {
      /* This is not an outgoing call so it cannot be CC monitor. */
      return;
   }

   sig_pri_lock_owner(pri, chanpos);
   owner = pri->pvts[chanpos]->owner;
   if (!owner) {
      return;
   }
   core_id = ast_cc_get_current_core_id(owner);
   if (core_id == -1) {
      /* No CC core setup */
      goto done;
   }

   cc_params = ast_channel_get_cc_config_params(owner);
   if (!cc_params) {
      /* Could not get CC config parameters. */
      goto done;
   }

#if defined(HAVE_PRI_CCSS)
   ast_channel_get_device_name(owner, device_name, sizeof(device_name));
   monitor = ast_cc_get_monitor_by_recall_core_id(core_id, device_name);
   if (monitor) {
      /* CC monitor is already present so no need for generic CC. */
      ao2_ref(monitor, -1);
      goto done;
   }
#endif   /* defined(HAVE_PRI_CCSS) */

   monitor_policy = ast_get_cc_monitor_policy(cc_params);
   switch (monitor_policy) {
   case AST_CC_MONITOR_NEVER:
      /* CCSS is not enabled. */
      break;
   case AST_CC_MONITOR_NATIVE:
      if (pri->sig == SIG_BRI_PTMP && pri->nodetype == PRI_NETWORK) {
         /* Request generic CC monitor. */
         ast_queue_cc_frame(owner, AST_CC_GENERIC_MONITOR_TYPE,
            sig_pri_get_orig_dialstring(pri->pvts[chanpos]), service, NULL);
      }
      break;
   case AST_CC_MONITOR_ALWAYS:
      if (pri->sig == SIG_BRI_PTMP && pri->nodetype != PRI_NETWORK) {
         /*
          * Cannot monitor PTMP TE side since this is not defined.
          * We are playing the roll of a phone in this case and
          * a phone cannot monitor a party over the network without
          * protocol help.
          */
         break;
      }
      /*
       * We are either falling back or this is a PTMP NT span.
       * Request generic CC monitor.
       */
      ast_queue_cc_frame(owner, AST_CC_GENERIC_MONITOR_TYPE,
         sig_pri_get_orig_dialstring(pri->pvts[chanpos]), service, NULL);
      break;
   case AST_CC_MONITOR_GENERIC:
      if (pri->sig == SIG_BRI_PTMP && pri->nodetype == PRI_NETWORK) {
         /* Request generic CC monitor. */
         ast_queue_cc_frame(owner, AST_CC_GENERIC_MONITOR_TYPE,
            sig_pri_get_orig_dialstring(pri->pvts[chanpos]), service, NULL);
      }
      break;
   }

done:
   ast_channel_unlock(owner);
}

#if defined(HAVE_PRI_CCSS)
/*!
 * \internal
 * \brief The CC link canceled the CC instance.
 * \since 1.8
 *
 * \param pri PRI span control structure.
 * \param cc_id CC record ID.
 * \param is_agent TRUE if the cc_id is for an agent.
 *
 * \return Nothing
 */
static void sig_pri_cc_link_canceled(struct sig_pri_span *pri, long cc_id, int is_agent)
{
   if (is_agent) {
      struct ast_cc_agent *agent;

      agent = sig_pri_find_cc_agent_by_cc_id(pri, cc_id);
      if (!agent) {
         return;
      }
      ast_cc_failed(agent->core_id, "%s agent got canceled by link",
         sig_pri_cc_type_name);
      ao2_ref(agent, -1);
   } else {
      struct sig_pri_cc_monitor_instance *monitor;

      monitor = sig_pri_find_cc_monitor_by_cc_id(pri, cc_id);
      if (!monitor) {
         return;
      }
      monitor->cc_id = -1;
      ast_cc_monitor_failed(monitor->core_id, monitor->name,
         "%s monitor got canceled by link", sig_pri_cc_type_name);
      ao2_ref(monitor, -1);
   }
}
#endif   /* defined(HAVE_PRI_CCSS) */

#if defined(HAVE_PRI_AOC_EVENTS)
/*!
 * \internal
 * \brief Convert ast_aoc_charged_item to PRI_AOC_CHARGED_ITEM .
 * \since 1.8
 *
 * \param value Value to convert to string.
 *
 * \return PRI_AOC_CHARGED_ITEM
 */
static enum PRI_AOC_CHARGED_ITEM sig_pri_aoc_charged_item_to_pri(enum PRI_AOC_CHARGED_ITEM value)
{
   switch (value) {
   case AST_AOC_CHARGED_ITEM_NA:
      return PRI_AOC_CHARGED_ITEM_NOT_AVAILABLE;
   case AST_AOC_CHARGED_ITEM_SPECIAL_ARRANGEMENT:
      return PRI_AOC_CHARGED_ITEM_SPECIAL_ARRANGEMENT;
   case AST_AOC_CHARGED_ITEM_BASIC_COMMUNICATION:
      return PRI_AOC_CHARGED_ITEM_BASIC_COMMUNICATION;
   case AST_AOC_CHARGED_ITEM_CALL_ATTEMPT:
      return PRI_AOC_CHARGED_ITEM_CALL_ATTEMPT;
   case AST_AOC_CHARGED_ITEM_CALL_SETUP:
      return PRI_AOC_CHARGED_ITEM_CALL_SETUP;
   case AST_AOC_CHARGED_ITEM_USER_USER_INFO:
      return PRI_AOC_CHARGED_ITEM_USER_USER_INFO;
   case AST_AOC_CHARGED_ITEM_SUPPLEMENTARY_SERVICE:
      return PRI_AOC_CHARGED_ITEM_SUPPLEMENTARY_SERVICE;
   }
   return PRI_AOC_CHARGED_ITEM_NOT_AVAILABLE;
}
#endif   /* defined(HAVE_PRI_AOC_EVENTS) */

#if defined(HAVE_PRI_AOC_EVENTS)
/*!
 * \internal
 * \brief Convert PRI_AOC_CHARGED_ITEM to ast_aoc_charged_item.
 * \since 1.8
 *
 * \param value Value to convert to string.
 *
 * \return ast_aoc_charged_item
 */
static enum ast_aoc_s_charged_item sig_pri_aoc_charged_item_to_ast(enum PRI_AOC_CHARGED_ITEM value)
{
   switch (value) {
   case PRI_AOC_CHARGED_ITEM_NOT_AVAILABLE:
      return AST_AOC_CHARGED_ITEM_NA;
   case PRI_AOC_CHARGED_ITEM_SPECIAL_ARRANGEMENT:
      return AST_AOC_CHARGED_ITEM_SPECIAL_ARRANGEMENT;
   case PRI_AOC_CHARGED_ITEM_BASIC_COMMUNICATION:
      return AST_AOC_CHARGED_ITEM_BASIC_COMMUNICATION;
   case PRI_AOC_CHARGED_ITEM_CALL_ATTEMPT:
      return AST_AOC_CHARGED_ITEM_CALL_ATTEMPT;
   case PRI_AOC_CHARGED_ITEM_CALL_SETUP:
      return AST_AOC_CHARGED_ITEM_CALL_SETUP;
   case PRI_AOC_CHARGED_ITEM_USER_USER_INFO:
      return AST_AOC_CHARGED_ITEM_USER_USER_INFO;
   case PRI_AOC_CHARGED_ITEM_SUPPLEMENTARY_SERVICE:
      return AST_AOC_CHARGED_ITEM_SUPPLEMENTARY_SERVICE;
   }
   return AST_AOC_CHARGED_ITEM_NA;
}
#endif   /* defined(HAVE_PRI_AOC_EVENTS) */

#if defined(HAVE_PRI_AOC_EVENTS)
/*!
 * \internal
 * \brief Convert AST_AOC_MULTIPLER to PRI_AOC_MULTIPLIER.
 * \since 1.8
 *
 * \return pri enum equivalent.
 */
static int sig_pri_aoc_multiplier_from_ast(enum ast_aoc_currency_multiplier mult)
{
   switch (mult) {
   case AST_AOC_MULT_ONETHOUSANDTH:
      return PRI_AOC_MULTIPLIER_THOUSANDTH;
   case AST_AOC_MULT_ONEHUNDREDTH:
      return PRI_AOC_MULTIPLIER_HUNDREDTH;
   case AST_AOC_MULT_ONETENTH:
      return PRI_AOC_MULTIPLIER_TENTH;
   case AST_AOC_MULT_ONE:
      return PRI_AOC_MULTIPLIER_ONE;
   case AST_AOC_MULT_TEN:
      return PRI_AOC_MULTIPLIER_TEN;
   case AST_AOC_MULT_HUNDRED:
      return PRI_AOC_MULTIPLIER_HUNDRED;
   case AST_AOC_MULT_THOUSAND:
      return PRI_AOC_MULTIPLIER_THOUSAND;
   default:
      return PRI_AOC_MULTIPLIER_ONE;
   }
}
#endif   /* defined(HAVE_PRI_AOC_EVENTS) */

#if defined(HAVE_PRI_AOC_EVENTS)
/*!
 * \internal
 * \brief Convert PRI_AOC_MULTIPLIER to AST_AOC_MULTIPLIER
 * \since 1.8
 *
 * \return ast enum equivalent.
 */
static int sig_pri_aoc_multiplier_from_pri(const int mult)
{
   switch (mult) {
   case PRI_AOC_MULTIPLIER_THOUSANDTH:
      return AST_AOC_MULT_ONETHOUSANDTH;
   case PRI_AOC_MULTIPLIER_HUNDREDTH:
      return AST_AOC_MULT_ONEHUNDREDTH;
   case PRI_AOC_MULTIPLIER_TENTH:
      return AST_AOC_MULT_ONETENTH;
   case PRI_AOC_MULTIPLIER_ONE:
      return AST_AOC_MULT_ONE;
   case PRI_AOC_MULTIPLIER_TEN:
      return AST_AOC_MULT_TEN;
   case PRI_AOC_MULTIPLIER_HUNDRED:
      return AST_AOC_MULT_HUNDRED;
   case PRI_AOC_MULTIPLIER_THOUSAND:
      return AST_AOC_MULT_THOUSAND;
   default:
      return AST_AOC_MULT_ONE;
   }
}
#endif   /* defined(HAVE_PRI_AOC_EVENTS) */

#if defined(HAVE_PRI_AOC_EVENTS)
/*!
 * \internal
 * \brief Convert ast_aoc_time_scale representation to PRI_AOC_TIME_SCALE
 * \since 1.8
 *
 * \param value Value to convert to ast representation
 *
 * \return PRI_AOC_TIME_SCALE
 */
static enum PRI_AOC_TIME_SCALE sig_pri_aoc_scale_to_pri(enum ast_aoc_time_scale value)
{
   switch (value) {
   default:
   case AST_AOC_TIME_SCALE_HUNDREDTH_SECOND:
      return PRI_AOC_TIME_SCALE_HUNDREDTH_SECOND;
   case AST_AOC_TIME_SCALE_TENTH_SECOND:
      return PRI_AOC_TIME_SCALE_TENTH_SECOND;
   case AST_AOC_TIME_SCALE_SECOND:
      return PRI_AOC_TIME_SCALE_SECOND;
   case AST_AOC_TIME_SCALE_TEN_SECOND:
      return PRI_AOC_TIME_SCALE_TEN_SECOND;
   case AST_AOC_TIME_SCALE_MINUTE:
      return PRI_AOC_TIME_SCALE_MINUTE;
   case AST_AOC_TIME_SCALE_HOUR:
      return PRI_AOC_TIME_SCALE_HOUR;
   case AST_AOC_TIME_SCALE_DAY:
      return PRI_AOC_TIME_SCALE_DAY;
   }
}
#endif   /* defined(HAVE_PRI_AOC_EVENTS) */

#if defined(HAVE_PRI_AOC_EVENTS)
/*!
 * \internal
 * \brief Convert PRI_AOC_TIME_SCALE to ast aoc representation
 * \since 1.8
 *
 * \param value Value to convert to ast representation
 *
 * \return ast aoc time scale
 */
static enum ast_aoc_time_scale sig_pri_aoc_scale_to_ast(enum PRI_AOC_TIME_SCALE value)
{
   switch (value) {
   default:
   case PRI_AOC_TIME_SCALE_HUNDREDTH_SECOND:
      return AST_AOC_TIME_SCALE_HUNDREDTH_SECOND;
   case PRI_AOC_TIME_SCALE_TENTH_SECOND:
      return AST_AOC_TIME_SCALE_TENTH_SECOND;
   case PRI_AOC_TIME_SCALE_SECOND:
      return AST_AOC_TIME_SCALE_SECOND;
   case PRI_AOC_TIME_SCALE_TEN_SECOND:
      return AST_AOC_TIME_SCALE_TEN_SECOND;
   case PRI_AOC_TIME_SCALE_MINUTE:
      return AST_AOC_TIME_SCALE_MINUTE;
   case PRI_AOC_TIME_SCALE_HOUR:
      return AST_AOC_TIME_SCALE_HOUR;
   case PRI_AOC_TIME_SCALE_DAY:
      return AST_AOC_TIME_SCALE_DAY;
   }
   return AST_AOC_TIME_SCALE_HUNDREDTH_SECOND;
}
#endif   /* defined(HAVE_PRI_AOC_EVENTS) */

#if defined(HAVE_PRI_AOC_EVENTS)
/*!
 * \internal
 * \brief Handle AOC-S control frame
 * \since 1.8
 *
 * \param aoc_s AOC-S event parameters.
 * \param owner Asterisk channel associated with the call.
 * \param passthrough indicating if this message should be queued on the ast channel
 *
 * \note Assumes the pri->lock is already obtained.
 * \note Assumes the sig_pri private is locked
 * \note Assumes the owner channel lock is already obtained.
 *
 * \return Nothing
 */
static void sig_pri_aoc_s_from_pri(const struct pri_subcmd_aoc_s *aoc_s, struct ast_channel *owner, int passthrough)
{
   struct ast_aoc_decoded *decoded = NULL;
   struct ast_aoc_encoded *encoded = NULL;
   size_t encoded_size = 0;
   int idx;

   if (!owner || !aoc_s) {
      return;
   }

   if (!(decoded = ast_aoc_create(AST_AOC_S, 0, 0))) {
      return;
   }

   for (idx = 0; idx < aoc_s->num_items; ++idx) {
      enum ast_aoc_s_charged_item charged_item;

      charged_item = sig_pri_aoc_charged_item_to_ast(aoc_s->item[idx].chargeable);
      if (charged_item == AST_AOC_CHARGED_ITEM_NA) {
         /* Delete the unknown charged item from the list. */
         continue;
      }
      switch (aoc_s->item[idx].rate_type) {
      case PRI_AOC_RATE_TYPE_DURATION:
         ast_aoc_s_add_rate_duration(decoded,
            charged_item,
            aoc_s->item[idx].rate.duration.amount.cost,
            sig_pri_aoc_multiplier_from_pri(aoc_s->item[idx].rate.duration.amount.multiplier),
            aoc_s->item[idx].rate.duration.currency,
            aoc_s->item[idx].rate.duration.time.length,
            sig_pri_aoc_scale_to_ast(aoc_s->item[idx].rate.duration.time.scale),
            aoc_s->item[idx].rate.duration.granularity.length,
            sig_pri_aoc_scale_to_ast(aoc_s->item[idx].rate.duration.granularity.scale),
            aoc_s->item[idx].rate.duration.charging_type);
         break;
      case PRI_AOC_RATE_TYPE_FLAT:
         ast_aoc_s_add_rate_flat(decoded,
            charged_item,
            aoc_s->item[idx].rate.flat.amount.cost,
            sig_pri_aoc_multiplier_from_pri(aoc_s->item[idx].rate.flat.amount.multiplier),
            aoc_s->item[idx].rate.flat.currency);
         break;
      case PRI_AOC_RATE_TYPE_VOLUME:
         ast_aoc_s_add_rate_volume(decoded,
            charged_item,
            aoc_s->item[idx].rate.volume.unit,
            aoc_s->item[idx].rate.volume.amount.cost,
            sig_pri_aoc_multiplier_from_pri(aoc_s->item[idx].rate.volume.amount.multiplier),
            aoc_s->item[idx].rate.volume.currency);
         break;
      case PRI_AOC_RATE_TYPE_SPECIAL_CODE:
         ast_aoc_s_add_rate_special_charge_code(decoded,
            charged_item,
            aoc_s->item[idx].rate.special);
         break;
      case PRI_AOC_RATE_TYPE_FREE:
         ast_aoc_s_add_rate_free(decoded, charged_item, 0);
         break;
      case PRI_AOC_RATE_TYPE_FREE_FROM_BEGINNING:
         ast_aoc_s_add_rate_free(decoded, charged_item, 1);
         break;
      default:
         ast_aoc_s_add_rate_na(decoded, charged_item);
         break;
      }
   }

   if (passthrough && (encoded = ast_aoc_encode(decoded, &encoded_size, owner))) {
      ast_queue_control_data(owner, AST_CONTROL_AOC, encoded, encoded_size);
   }

   ast_aoc_manager_event(decoded, owner);

   ast_aoc_destroy_decoded(decoded);
   ast_aoc_destroy_encoded(encoded);
}
#endif   /* defined(HAVE_PRI_AOC_EVENTS) */

#if defined(HAVE_PRI_AOC_EVENTS)
/*!
 * \internal
 * \brief Generate AOC Request Response
 * \since 1.8
 *
 * \param aoc_request
 *
 * \note Assumes the pri->lock is already obtained.
 * \note Assumes the sig_pri private is locked
 * \note Assumes the owner channel lock is already obtained.
 *
 * \return Nothing
 */
static void sig_pri_aoc_request_from_pri(const struct pri_subcmd_aoc_request *aoc_request, struct sig_pri_chan *pvt, q931_call *call)
{
   int request;

   if (!aoc_request) {
      return;
   }

   request = aoc_request->charging_request;

   if (request & PRI_AOC_REQUEST_S) {
      if (pvt->pri->aoc_passthrough_flag & SIG_PRI_AOC_GRANT_S) {
         /* An AOC-S response must come from the other side, so save off this invoke_id
          * and see if an AOC-S message comes in before the call is answered. */
         pvt->aoc_s_request_invoke_id = aoc_request->invoke_id;
         pvt->aoc_s_request_invoke_id_valid = 1;

      } else {
         pri_aoc_s_request_response_send(pvt->pri->pri,
            call,
            aoc_request->invoke_id,
            NULL);
      }
   }

   if (request & PRI_AOC_REQUEST_D) {
      if (pvt->pri->aoc_passthrough_flag & SIG_PRI_AOC_GRANT_D) {
         pri_aoc_de_request_response_send(pvt->pri->pri,
            call,
            PRI_AOC_REQ_RSP_CHARGING_INFO_FOLLOWS,
            aoc_request->invoke_id);
      } else {
         pri_aoc_de_request_response_send(pvt->pri->pri,
            call,
            PRI_AOC_REQ_RSP_ERROR_NOT_AVAILABLE,
            aoc_request->invoke_id);
      }
   }

   if (request & PRI_AOC_REQUEST_E) {
      if (pvt->pri->aoc_passthrough_flag & SIG_PRI_AOC_GRANT_E) {
         pri_aoc_de_request_response_send(pvt->pri->pri,
            call,
            PRI_AOC_REQ_RSP_CHARGING_INFO_FOLLOWS,
            aoc_request->invoke_id);
      } else {
         pri_aoc_de_request_response_send(pvt->pri->pri,
            call,
            PRI_AOC_REQ_RSP_ERROR_NOT_AVAILABLE,
            aoc_request->invoke_id);
      }
   }
}
#endif   /* defined(HAVE_PRI_AOC_EVENTS) */

#if defined(HAVE_PRI_AOC_EVENTS)
/*!
 * \internal
 * \brief Generate AOC-D AST_CONTROL_AOC frame
 * \since 1.8
 *
 * \param aoc_e AOC-D event parameters.
 * \param owner Asterisk channel associated with the call.
 * \param passthrough indicating if this message should be queued on the ast channel
 *
 * \note Assumes the pri->lock is already obtained.
 * \note Assumes the sig_pri private is locked
 * \note Assumes the owner channel lock is already obtained.
 *
 * \return Nothing
 */
static void sig_pri_aoc_d_from_pri(const struct pri_subcmd_aoc_d *aoc_d, struct ast_channel *owner, int passthrough)
{
   struct ast_aoc_decoded *decoded = NULL;
   struct ast_aoc_encoded *encoded = NULL;
   size_t encoded_size = 0;
   enum ast_aoc_charge_type type;

   if (!owner || !aoc_d) {
      return;
   }

   switch (aoc_d->charge) {
   case PRI_AOC_DE_CHARGE_CURRENCY:
      type = AST_AOC_CHARGE_CURRENCY;
      break;
   case PRI_AOC_DE_CHARGE_UNITS:
      type = AST_AOC_CHARGE_UNIT;
      break;
   case PRI_AOC_DE_CHARGE_FREE:
      type = AST_AOC_CHARGE_FREE;
      break;
   default:
      type = AST_AOC_CHARGE_NA;
      break;
   }

   if (!(decoded = ast_aoc_create(AST_AOC_D, type, 0))) {
      return;
   }

   switch (aoc_d->billing_accumulation) {
   default:
      ast_debug(1, "AOC-D billing accumulation has unknown value: %d\n",
         aoc_d->billing_accumulation);
      /* Fall through */
   case 0:/* subTotal */
      ast_aoc_set_total_type(decoded, AST_AOC_SUBTOTAL);
      break;
   case 1:/* total */
      ast_aoc_set_total_type(decoded, AST_AOC_TOTAL);
      break;
   }

   switch (aoc_d->billing_id) {
   case PRI_AOC_D_BILLING_ID_NORMAL:
      ast_aoc_set_billing_id(decoded, AST_AOC_BILLING_NORMAL);
      break;
   case PRI_AOC_D_BILLING_ID_REVERSE:
      ast_aoc_set_billing_id(decoded, AST_AOC_BILLING_REVERSE_CHARGE);
      break;
   case PRI_AOC_D_BILLING_ID_CREDIT_CARD:
      ast_aoc_set_billing_id(decoded, AST_AOC_BILLING_CREDIT_CARD);
      break;
   case PRI_AOC_D_BILLING_ID_NOT_AVAILABLE:
   default:
      ast_aoc_set_billing_id(decoded, AST_AOC_BILLING_NA);
      break;
   }

   switch (aoc_d->charge) {
   case PRI_AOC_DE_CHARGE_CURRENCY:
      ast_aoc_set_currency_info(decoded,
         aoc_d->recorded.money.amount.cost,
         sig_pri_aoc_multiplier_from_pri(aoc_d->recorded.money.amount.multiplier),
         aoc_d->recorded.money.currency);
      break;
   case PRI_AOC_DE_CHARGE_UNITS:
      {
         int i;
         for (i = 0; i < aoc_d->recorded.unit.num_items; ++i) {
            /* if type or number are negative, then they are not present */
            ast_aoc_add_unit_entry(decoded,
               (aoc_d->recorded.unit.item[i].number >= 0 ? 1 : 0),
               aoc_d->recorded.unit.item[i].number,
               (aoc_d->recorded.unit.item[i].type >= 0 ? 1 : 0),
               aoc_d->recorded.unit.item[i].type);
         }
      }
      break;
   }

   if (passthrough && (encoded = ast_aoc_encode(decoded, &encoded_size, owner))) {
      ast_queue_control_data(owner, AST_CONTROL_AOC, encoded, encoded_size);
   }

   ast_aoc_manager_event(decoded, owner);

   ast_aoc_destroy_decoded(decoded);
   ast_aoc_destroy_encoded(encoded);
}
#endif   /* defined(HAVE_PRI_AOC_EVENTS) */

#if defined(HAVE_PRI_AOC_EVENTS)
/*!
 * \internal
 * \brief Generate AOC-E AST_CONTROL_AOC frame
 * \since 1.8
 *
 * \param aoc_e AOC-E event parameters.
 * \param owner Asterisk channel associated with the call.
 * \param passthrough indicating if this message should be queued on the ast channel
 *
 * \note Assumes the pri->lock is already obtained.
 * \note Assumes the sig_pri private is locked
 * \note Assumes the owner channel lock is already obtained.
 * \note owner channel may be NULL. In that case, generate event only
 *
 * \return Nothing
 */
static void sig_pri_aoc_e_from_pri(const struct pri_subcmd_aoc_e *aoc_e, struct ast_channel *owner, int passthrough)
{
   struct ast_aoc_decoded *decoded = NULL;
   struct ast_aoc_encoded *encoded = NULL;
   size_t encoded_size = 0;
   enum ast_aoc_charge_type type;

   if (!aoc_e) {
      return;
   }

   switch (aoc_e->charge) {
   case PRI_AOC_DE_CHARGE_CURRENCY:
      type = AST_AOC_CHARGE_CURRENCY;
      break;
   case PRI_AOC_DE_CHARGE_UNITS:
      type = AST_AOC_CHARGE_UNIT;
      break;
   case PRI_AOC_DE_CHARGE_FREE:
      type = AST_AOC_CHARGE_FREE;
      break;
   default:
      type = AST_AOC_CHARGE_NA;
      break;
   }

   if (!(decoded = ast_aoc_create(AST_AOC_E, type, 0))) {
      return;
   }

   switch (aoc_e->associated.charging_type) {
   case PRI_AOC_E_CHARGING_ASSOCIATION_NUMBER:
      if (!aoc_e->associated.charge.number.valid) {
         break;
      }
      ast_aoc_set_association_number(decoded, aoc_e->associated.charge.number.str, aoc_e->associated.charge.number.plan);
      break;
   case PRI_AOC_E_CHARGING_ASSOCIATION_ID:
      ast_aoc_set_association_id(decoded, aoc_e->associated.charge.id);
      break;
   default:
      break;
   }

   switch (aoc_e->billing_id) {
   case PRI_AOC_E_BILLING_ID_NORMAL:
      ast_aoc_set_billing_id(decoded, AST_AOC_BILLING_NORMAL);
      break;
   case PRI_AOC_E_BILLING_ID_REVERSE:
      ast_aoc_set_billing_id(decoded, AST_AOC_BILLING_REVERSE_CHARGE);
      break;
   case PRI_AOC_E_BILLING_ID_CREDIT_CARD:
      ast_aoc_set_billing_id(decoded, AST_AOC_BILLING_CREDIT_CARD);
      break;
   case PRI_AOC_E_BILLING_ID_CALL_FORWARDING_UNCONDITIONAL:
      ast_aoc_set_billing_id(decoded, AST_AOC_BILLING_CALL_FWD_UNCONDITIONAL);
      break;
   case PRI_AOC_E_BILLING_ID_CALL_FORWARDING_BUSY:
      ast_aoc_set_billing_id(decoded, AST_AOC_BILLING_CALL_FWD_BUSY);
      break;
   case PRI_AOC_E_BILLING_ID_CALL_FORWARDING_NO_REPLY:
      ast_aoc_set_billing_id(decoded, AST_AOC_BILLING_CALL_FWD_NO_REPLY);
      break;
   case PRI_AOC_E_BILLING_ID_CALL_DEFLECTION:
      ast_aoc_set_billing_id(decoded, AST_AOC_BILLING_CALL_DEFLECTION);
      break;
   case PRI_AOC_E_BILLING_ID_CALL_TRANSFER:
      ast_aoc_set_billing_id(decoded, AST_AOC_BILLING_CALL_TRANSFER);
      break;
   case PRI_AOC_E_BILLING_ID_NOT_AVAILABLE:
   default:
      ast_aoc_set_billing_id(decoded, AST_AOC_BILLING_NA);
      break;
   }

   switch (aoc_e->charge) {
   case PRI_AOC_DE_CHARGE_CURRENCY:
      ast_aoc_set_currency_info(decoded,
         aoc_e->recorded.money.amount.cost,
         sig_pri_aoc_multiplier_from_pri(aoc_e->recorded.money.amount.multiplier),
         aoc_e->recorded.money.currency);
      break;
   case PRI_AOC_DE_CHARGE_UNITS:
      {
         int i;
         for (i = 0; i < aoc_e->recorded.unit.num_items; ++i) {
            /* if type or number are negative, then they are not present */
            ast_aoc_add_unit_entry(decoded,
               (aoc_e->recorded.unit.item[i].number >= 0 ? 1 : 0),
               aoc_e->recorded.unit.item[i].number,
               (aoc_e->recorded.unit.item[i].type >= 0 ? 1 : 0),
               aoc_e->recorded.unit.item[i].type);
         }
      }
   }

   if (passthrough && owner && (encoded = ast_aoc_encode(decoded, &encoded_size, owner))) {
      ast_queue_control_data(owner, AST_CONTROL_AOC, encoded, encoded_size);
   }

   ast_aoc_manager_event(decoded, owner);

   ast_aoc_destroy_decoded(decoded);
   ast_aoc_destroy_encoded(encoded);
}
#endif   /* defined(HAVE_PRI_AOC_EVENTS) */

#if defined(HAVE_PRI_AOC_EVENTS)
/*!
 * \internal
 * \brief send an AOC-S message on the current call
 *
 * \param pvt sig_pri private channel structure.
 * \param generic decoded ast AOC message
 *
 * \return Nothing
 *
 * \note Assumes that the PRI lock is already obtained.
 */
static void sig_pri_aoc_s_from_ast(struct sig_pri_chan *pvt, struct ast_aoc_decoded *decoded)
{
   struct pri_subcmd_aoc_s aoc_s = { 0, };
   const struct ast_aoc_s_entry *entry;
   int idx;

   for (idx = 0; idx < ast_aoc_s_get_count(decoded); idx++) {
      if (!(entry = ast_aoc_s_get_rate_info(decoded, idx))) {
         break;
      }

      aoc_s.item[idx].chargeable = sig_pri_aoc_charged_item_to_pri(entry->charged_item);

      switch (entry->rate_type) {
      case AST_AOC_RATE_TYPE_DURATION:
         aoc_s.item[idx].rate_type = PRI_AOC_RATE_TYPE_DURATION;
         aoc_s.item[idx].rate.duration.amount.cost = entry->rate.duration.amount;
         aoc_s.item[idx].rate.duration.amount.multiplier =
            sig_pri_aoc_multiplier_from_ast(entry->rate.duration.multiplier);
         aoc_s.item[idx].rate.duration.time.length = entry->rate.duration.time;
         aoc_s.item[idx].rate.duration.time.scale =
            sig_pri_aoc_scale_to_pri(entry->rate.duration.time_scale);
         aoc_s.item[idx].rate.duration.granularity.length = entry->rate.duration.granularity_time;
         aoc_s.item[idx].rate.duration.granularity.scale =
            sig_pri_aoc_scale_to_pri(entry->rate.duration.granularity_time_scale);
         aoc_s.item[idx].rate.duration.charging_type = entry->rate.duration.charging_type;

         if (!ast_strlen_zero(entry->rate.duration.currency_name)) {
            ast_copy_string(aoc_s.item[idx].rate.duration.currency,
               entry->rate.duration.currency_name,
               sizeof(aoc_s.item[idx].rate.duration.currency));
         }
         break;
      case AST_AOC_RATE_TYPE_FLAT:
         aoc_s.item[idx].rate_type = PRI_AOC_RATE_TYPE_FLAT;
         aoc_s.item[idx].rate.flat.amount.cost = entry->rate.flat.amount;
         aoc_s.item[idx].rate.flat.amount.multiplier =
            sig_pri_aoc_multiplier_from_ast(entry->rate.flat.multiplier);

         if (!ast_strlen_zero(entry->rate.flat.currency_name)) {
            ast_copy_string(aoc_s.item[idx].rate.flat.currency,
               entry->rate.flat.currency_name,
               sizeof(aoc_s.item[idx].rate.flat.currency));
         }
         break;
      case AST_AOC_RATE_TYPE_VOLUME:
         aoc_s.item[idx].rate_type = PRI_AOC_RATE_TYPE_VOLUME;
         aoc_s.item[idx].rate.volume.unit = entry->rate.volume.volume_unit;
         aoc_s.item[idx].rate.volume.amount.cost = entry->rate.volume.amount;
         aoc_s.item[idx].rate.volume.amount.multiplier =
            sig_pri_aoc_multiplier_from_ast(entry->rate.volume.multiplier);

         if (!ast_strlen_zero(entry->rate.volume.currency_name)) {
            ast_copy_string(aoc_s.item[idx].rate.volume.currency,
               entry->rate.volume.currency_name,
               sizeof(aoc_s.item[idx].rate.volume.currency));
         }
         break;
      case AST_AOC_RATE_TYPE_SPECIAL_CODE:
         aoc_s.item[idx].rate_type = PRI_AOC_RATE_TYPE_SPECIAL_CODE;
         aoc_s.item[idx].rate.special = entry->rate.special_code;
         break;
      case AST_AOC_RATE_TYPE_FREE:
         aoc_s.item[idx].rate_type = PRI_AOC_RATE_TYPE_FREE;
         break;
      case AST_AOC_RATE_TYPE_FREE_FROM_BEGINNING:
         aoc_s.item[idx].rate_type = PRI_AOC_RATE_TYPE_FREE_FROM_BEGINNING;
         break;
      default:
      case AST_AOC_RATE_TYPE_NA:
         aoc_s.item[idx].rate_type = PRI_AOC_RATE_TYPE_NOT_AVAILABLE;
         break;
      }
   }
   aoc_s.num_items = idx;

   /* if this rate should be sent as a response to an AOC-S request we will
    * have an aoc_s_request_invoke_id associated with this pvt */
   if (pvt->aoc_s_request_invoke_id_valid) {
      pri_aoc_s_request_response_send(pvt->pri->pri, pvt->call, pvt->aoc_s_request_invoke_id, &aoc_s);
      pvt->aoc_s_request_invoke_id_valid = 0;
   } else {
      pri_aoc_s_send(pvt->pri->pri, pvt->call, &aoc_s);
   }
}
#endif   /* defined(HAVE_PRI_AOC_EVENTS) */

#if defined(HAVE_PRI_AOC_EVENTS)
/*!
 * \internal
 * \brief send an AOC-D message on the current call
 *
 * \param pvt sig_pri private channel structure.
 * \param generic decoded ast AOC message
 *
 * \return Nothing
 *
 * \note Assumes that the PRI lock is already obtained.
 */
static void sig_pri_aoc_d_from_ast(struct sig_pri_chan *pvt, struct ast_aoc_decoded *decoded)
{
   struct pri_subcmd_aoc_d aoc_d = { 0, };

   aoc_d.billing_accumulation = (ast_aoc_get_total_type(decoded) == AST_AOC_TOTAL) ? 1 : 0;

   switch (ast_aoc_get_billing_id(decoded)) {
   case AST_AOC_BILLING_NORMAL:
      aoc_d.billing_id = PRI_AOC_D_BILLING_ID_NORMAL;
      break;
   case AST_AOC_BILLING_REVERSE_CHARGE:
      aoc_d.billing_id = PRI_AOC_D_BILLING_ID_REVERSE;
      break;
   case AST_AOC_BILLING_CREDIT_CARD:
      aoc_d.billing_id = PRI_AOC_D_BILLING_ID_CREDIT_CARD;
      break;
   case AST_AOC_BILLING_NA:
   default:
      aoc_d.billing_id = PRI_AOC_D_BILLING_ID_NOT_AVAILABLE;
      break;
   }

   switch (ast_aoc_get_charge_type(decoded)) {
   case AST_AOC_CHARGE_FREE:
      aoc_d.charge = PRI_AOC_DE_CHARGE_FREE;
      break;
   case AST_AOC_CHARGE_CURRENCY:
      {
         const char *currency_name = ast_aoc_get_currency_name(decoded);
         aoc_d.charge = PRI_AOC_DE_CHARGE_CURRENCY;
         aoc_d.recorded.money.amount.cost = ast_aoc_get_currency_amount(decoded);
         aoc_d.recorded.money.amount.multiplier = sig_pri_aoc_multiplier_from_ast(ast_aoc_get_currency_multiplier(decoded));
         if (!ast_strlen_zero(currency_name)) {
            ast_copy_string(aoc_d.recorded.money.currency, currency_name, sizeof(aoc_d.recorded.money.currency));
         }
      }
      break;
   case AST_AOC_CHARGE_UNIT:
      {
         const struct ast_aoc_unit_entry *entry;
         int i;
         aoc_d.charge = PRI_AOC_DE_CHARGE_UNITS;
         for (i = 0; i < ast_aoc_get_unit_count(decoded); i++) {
            if ((entry = ast_aoc_get_unit_info(decoded, i)) && i < ARRAY_LEN(aoc_d.recorded.unit.item)) {
               if (entry->valid_amount) {
                  aoc_d.recorded.unit.item[i].number = entry->amount;
               } else {
                  aoc_d.recorded.unit.item[i].number = -1;
               }
               if (entry->valid_type) {
                  aoc_d.recorded.unit.item[i].type = entry->type;
               } else {
                  aoc_d.recorded.unit.item[i].type = -1;
               }
               aoc_d.recorded.unit.num_items++;
            } else {
               break;
            }
         }
      }
      break;
   case AST_AOC_CHARGE_NA:
   default:
      aoc_d.charge = PRI_AOC_DE_CHARGE_NOT_AVAILABLE;
      break;
   }

   pri_aoc_d_send(pvt->pri->pri, pvt->call, &aoc_d);
}
#endif   /* defined(HAVE_PRI_AOC_EVENTS) */

#if defined(HAVE_PRI_AOC_EVENTS)
/*!
 * \internal
 * \brief send an AOC-E message on the current call
 *
 * \param pvt sig_pri private channel structure.
 * \param generic decoded ast AOC message
 *
 * \return Nothing
 *
 * \note Assumes that the PRI lock is already obtained.
 */
static void sig_pri_aoc_e_from_ast(struct sig_pri_chan *pvt, struct ast_aoc_decoded *decoded)
{
   struct pri_subcmd_aoc_e *aoc_e = &pvt->aoc_e;
   const struct ast_aoc_charging_association *ca = ast_aoc_get_association_info(decoded);

   memset(aoc_e, 0, sizeof(*aoc_e));
   pvt->holding_aoce = 1;

   switch (ca->charging_type) {
   case AST_AOC_CHARGING_ASSOCIATION_NUMBER:
      aoc_e->associated.charge.number.valid = 1;
      ast_copy_string(aoc_e->associated.charge.number.str,
         ca->charge.number.number,
         sizeof(aoc_e->associated.charge.number.str));
      aoc_e->associated.charge.number.plan = ca->charge.number.plan;
      aoc_e->associated.charging_type = PRI_AOC_E_CHARGING_ASSOCIATION_NUMBER;
      break;
   case AST_AOC_CHARGING_ASSOCIATION_ID:
      aoc_e->associated.charge.id = ca->charge.id;
      aoc_e->associated.charging_type = PRI_AOC_E_CHARGING_ASSOCIATION_ID;
      break;
   case AST_AOC_CHARGING_ASSOCIATION_NA:
   default:
      break;
   }

   switch (ast_aoc_get_billing_id(decoded)) {
   case AST_AOC_BILLING_NORMAL:
      aoc_e->billing_id = PRI_AOC_E_BILLING_ID_NORMAL;
      break;
   case AST_AOC_BILLING_REVERSE_CHARGE:
      aoc_e->billing_id = PRI_AOC_E_BILLING_ID_REVERSE;
      break;
   case AST_AOC_BILLING_CREDIT_CARD:
      aoc_e->billing_id = PRI_AOC_E_BILLING_ID_CREDIT_CARD;
      break;
   case AST_AOC_BILLING_CALL_FWD_UNCONDITIONAL:
      aoc_e->billing_id = PRI_AOC_E_BILLING_ID_CALL_FORWARDING_UNCONDITIONAL;
      break;
   case AST_AOC_BILLING_CALL_FWD_BUSY:
      aoc_e->billing_id = PRI_AOC_E_BILLING_ID_CALL_FORWARDING_BUSY;
      break;
   case AST_AOC_BILLING_CALL_FWD_NO_REPLY:
      aoc_e->billing_id = PRI_AOC_E_BILLING_ID_CALL_FORWARDING_NO_REPLY;
      break;
   case AST_AOC_BILLING_CALL_DEFLECTION:
      aoc_e->billing_id = PRI_AOC_E_BILLING_ID_CALL_DEFLECTION;
      break;
   case AST_AOC_BILLING_CALL_TRANSFER:
      aoc_e->billing_id = PRI_AOC_E_BILLING_ID_CALL_TRANSFER;
      break;
   case AST_AOC_BILLING_NA:
   default:
      aoc_e->billing_id = PRI_AOC_E_BILLING_ID_NOT_AVAILABLE;
      break;
   }

   switch (ast_aoc_get_charge_type(decoded)) {
   case AST_AOC_CHARGE_FREE:
      aoc_e->charge = PRI_AOC_DE_CHARGE_FREE;
      break;
   case AST_AOC_CHARGE_CURRENCY:
      {
         const char *currency_name = ast_aoc_get_currency_name(decoded);
         aoc_e->charge = PRI_AOC_DE_CHARGE_CURRENCY;
         aoc_e->recorded.money.amount.cost = ast_aoc_get_currency_amount(decoded);
         aoc_e->recorded.money.amount.multiplier = sig_pri_aoc_multiplier_from_ast(ast_aoc_get_currency_multiplier(decoded));
         if (!ast_strlen_zero(currency_name)) {
            ast_copy_string(aoc_e->recorded.money.currency, currency_name, sizeof(aoc_e->recorded.money.currency));
         }
      }
      break;
   case AST_AOC_CHARGE_UNIT:
      {
         const struct ast_aoc_unit_entry *entry;
         int i;
         aoc_e->charge = PRI_AOC_DE_CHARGE_UNITS;
         for (i = 0; i < ast_aoc_get_unit_count(decoded); i++) {
            if ((entry = ast_aoc_get_unit_info(decoded, i)) && i < ARRAY_LEN(aoc_e->recorded.unit.item)) {
               if (entry->valid_amount) {
                  aoc_e->recorded.unit.item[i].number = entry->amount;
               } else {
                  aoc_e->recorded.unit.item[i].number = -1;
               }
               if (entry->valid_type) {
                  aoc_e->recorded.unit.item[i].type = entry->type;
               } else {
                  aoc_e->recorded.unit.item[i].type = -1;
               }
               aoc_e->recorded.unit.num_items++;
            }
         }
      }
      break;
   case AST_AOC_CHARGE_NA:
   default:
      aoc_e->charge = PRI_AOC_DE_CHARGE_NOT_AVAILABLE;
      break;
   }
}
#endif   /* defined(HAVE_PRI_AOC_EVENTS) */

#if defined(HAVE_PRI_AOC_EVENTS)
/*!
 * \internal
 * \brief send an AOC-E termination request on ast_channel and set
 * hangup delay.
 *
 * \param pri PRI span control structure.
 * \param chanpos Channel position in the span.
 * \param ms to delay hangup
 *
 * \note Assumes the pri->lock is already obtained.
 * \note Assumes the sig_pri_lock_private(pri->pvts[chanpos]) is already obtained.
 *
 * \return Nothing
 */
static void sig_pri_send_aoce_termination_request(struct sig_pri_span *pri, int chanpos, unsigned int ms)
{
   struct sig_pri_chan *pvt;
   struct ast_aoc_decoded *decoded = NULL;
   struct ast_aoc_encoded *encoded = NULL;
   size_t encoded_size;
   struct timeval whentohangup = { 0, };

   sig_pri_lock_owner(pri, chanpos);
   pvt = pri->pvts[chanpos];
   if (!pvt->owner) {
      return;
   }

   if (!(decoded = ast_aoc_create(AST_AOC_REQUEST, 0, AST_AOC_REQUEST_E))) {
      ast_softhangup_nolock(pvt->owner, AST_SOFTHANGUP_DEV);
      goto cleanup_termination_request;
   }

   ast_aoc_set_termination_request(decoded);

   if (!(encoded = ast_aoc_encode(decoded, &encoded_size, pvt->owner))) {
      ast_softhangup_nolock(pvt->owner, AST_SOFTHANGUP_DEV);
      goto cleanup_termination_request;
   }

   /* convert ms to timeval */
   whentohangup.tv_usec = (ms % 1000) * 1000;
   whentohangup.tv_sec = ms / 1000;

   if (ast_queue_control_data(pvt->owner, AST_CONTROL_AOC, encoded, encoded_size)) {
      ast_softhangup_nolock(pvt->owner, AST_SOFTHANGUP_DEV);
      goto cleanup_termination_request;
   }

   pvt->waiting_for_aoce = 1;
   ast_channel_setwhentohangup_tv(pvt->owner, whentohangup);
   ast_debug(1, "Delaying hangup on %s for aoc-e msg\n", ast_channel_name(pvt->owner));

cleanup_termination_request:
   ast_channel_unlock(pvt->owner);
   ast_aoc_destroy_decoded(decoded);
   ast_aoc_destroy_encoded(encoded);
}
#endif   /* defined(HAVE_PRI_AOC_EVENTS) */

/*!
 * \internal
 * \brief TRUE if PRI event came in on a CIS call.
 * \since 1.8
 *
 * \param channel PRI encoded span/channel
 *
 * \retval non-zero if CIS call.
 */
static int sig_pri_is_cis_call(int channel)
{
   return channel != -1 && (channel & PRI_CIS_CALL);
}

/*!
 * \internal
 * \brief Handle the CIS associated PRI subcommand events.
 * \since 1.8
 *
 * \param pri PRI span control structure.
 * \param event_id PRI event id
 * \param subcmds Subcommands to process if any. (Could be NULL).
 * \param call_rsp libpri opaque call structure to send any responses toward.
 * Could be NULL either because it is not available or the call is for the
 * dummy call reference.  However, this should not be NULL in the cases that
 * need to use the pointer to send a response message back.
 *
 * \note Assumes the pri->lock is already obtained.
 *
 * \return Nothing
 */
static void sig_pri_handle_cis_subcmds(struct sig_pri_span *pri, int event_id,
   const struct pri_subcommands *subcmds, q931_call *call_rsp)
{
   int index;
#if defined(HAVE_PRI_CCSS)
   struct ast_cc_agent *agent;
   struct sig_pri_cc_agent_prv *agent_prv;
   struct sig_pri_cc_monitor_instance *monitor;
#endif   /* defined(HAVE_PRI_CCSS) */

   if (!subcmds) {
      return;
   }
   for (index = 0; index < subcmds->counter_subcmd; ++index) {
      const struct pri_subcommand *subcmd = &subcmds->subcmd[index];

      switch (subcmd->cmd) {
#if defined(STATUS_REQUEST_PLACE_HOLDER)
      case PRI_SUBCMD_STATUS_REQ:
      case PRI_SUBCMD_STATUS_REQ_RSP:
         /* Ignore for now. */
         break;
#endif   /* defined(STATUS_REQUEST_PLACE_HOLDER) */
#if defined(HAVE_PRI_CCSS)
      case PRI_SUBCMD_CC_REQ:
         agent = sig_pri_find_cc_agent_by_cc_id(pri, subcmd->u.cc_request.cc_id);
         if (!agent) {
            pri_cc_cancel(pri->pri, subcmd->u.cc_request.cc_id);
            break;
         }
         if (!ast_cc_request_is_within_limits()) {
            if (pri_cc_req_rsp(pri->pri, subcmd->u.cc_request.cc_id,
               5/* queue_full */)) {
               pri_cc_cancel(pri->pri, subcmd->u.cc_request.cc_id);
            }
            ast_cc_failed(agent->core_id, "%s agent system CC queue full",
               sig_pri_cc_type_name);
            ao2_ref(agent, -1);
            break;
         }
         agent_prv = agent->private_data;
         agent_prv->cc_request_response_pending = 1;
         if (ast_cc_agent_accept_request(agent->core_id,
            "%s caller accepted CC offer.", sig_pri_cc_type_name)) {
            agent_prv->cc_request_response_pending = 0;
            if (pri_cc_req_rsp(pri->pri, subcmd->u.cc_request.cc_id,
               2/* short_term_denial */)) {
               pri_cc_cancel(pri->pri, subcmd->u.cc_request.cc_id);
            }
            ast_cc_failed(agent->core_id, "%s agent CC core request accept failed",
               sig_pri_cc_type_name);
         }
         ao2_ref(agent, -1);
         break;
#endif   /* defined(HAVE_PRI_CCSS) */
#if defined(HAVE_PRI_CCSS)
      case PRI_SUBCMD_CC_REQ_RSP:
         monitor = sig_pri_find_cc_monitor_by_cc_id(pri,
            subcmd->u.cc_request_rsp.cc_id);
         if (!monitor) {
            pri_cc_cancel(pri->pri, subcmd->u.cc_request_rsp.cc_id);
            break;
         }
         switch (subcmd->u.cc_request_rsp.status) {
         case 0:/* success */
            ast_cc_monitor_request_acked(monitor->core_id,
               "%s far end accepted CC request", sig_pri_cc_type_name);
            break;
         case 1:/* timeout */
            ast_verb(2, "core_id:%d %s CC request timeout\n", monitor->core_id,
               sig_pri_cc_type_name);
            ast_cc_monitor_failed(monitor->core_id, monitor->name,
               "%s CC request timeout", sig_pri_cc_type_name);
            break;
         case 2:/* error */
            ast_verb(2, "core_id:%d %s CC request error: %s\n", monitor->core_id,
               sig_pri_cc_type_name,
               pri_facility_error2str(subcmd->u.cc_request_rsp.fail_code));
            ast_cc_monitor_failed(monitor->core_id, monitor->name,
               "%s CC request error", sig_pri_cc_type_name);
            break;
         case 3:/* reject */
            ast_verb(2, "core_id:%d %s CC request reject: %s\n", monitor->core_id,
               sig_pri_cc_type_name,
               pri_facility_reject2str(subcmd->u.cc_request_rsp.fail_code));
            ast_cc_monitor_failed(monitor->core_id, monitor->name,
               "%s CC request reject", sig_pri_cc_type_name);
            break;
         default:
            ast_verb(2, "core_id:%d %s CC request unknown status %d\n",
               monitor->core_id, sig_pri_cc_type_name,
               subcmd->u.cc_request_rsp.status);
            ast_cc_monitor_failed(monitor->core_id, monitor->name,
               "%s CC request unknown status", sig_pri_cc_type_name);
            break;
         }
         ao2_ref(monitor, -1);
         break;
#endif   /* defined(HAVE_PRI_CCSS) */
#if defined(HAVE_PRI_CCSS)
      case PRI_SUBCMD_CC_REMOTE_USER_FREE:
         monitor = sig_pri_find_cc_monitor_by_cc_id(pri,
            subcmd->u.cc_remote_user_free.cc_id);
         if (!monitor) {
            pri_cc_cancel(pri->pri, subcmd->u.cc_remote_user_free.cc_id);
            break;
         }
         ast_cc_monitor_callee_available(monitor->core_id,
            "%s callee has become available", sig_pri_cc_type_name);
         ao2_ref(monitor, -1);
         break;
#endif   /* defined(HAVE_PRI_CCSS) */
#if defined(HAVE_PRI_CCSS)
      case PRI_SUBCMD_CC_B_FREE:
         monitor = sig_pri_find_cc_monitor_by_cc_id(pri,
            subcmd->u.cc_b_free.cc_id);
         if (!monitor) {
            pri_cc_cancel(pri->pri, subcmd->u.cc_b_free.cc_id);
            break;
         }
         ast_cc_monitor_party_b_free(monitor->core_id);
         ao2_ref(monitor, -1);
         break;
#endif   /* defined(HAVE_PRI_CCSS) */
#if defined(HAVE_PRI_CCSS)
      case PRI_SUBCMD_CC_STATUS_REQ:
         monitor = sig_pri_find_cc_monitor_by_cc_id(pri,
            subcmd->u.cc_status_req.cc_id);
         if (!monitor) {
            pri_cc_cancel(pri->pri, subcmd->u.cc_status_req.cc_id);
            break;
         }
         ast_cc_monitor_status_request(monitor->core_id);
         ao2_ref(monitor, -1);
         break;
#endif   /* defined(HAVE_PRI_CCSS) */
#if defined(HAVE_PRI_CCSS)
      case PRI_SUBCMD_CC_STATUS_REQ_RSP:
         agent = sig_pri_find_cc_agent_by_cc_id(pri, subcmd->u.cc_status_req_rsp.cc_id);
         if (!agent) {
            pri_cc_cancel(pri->pri, subcmd->u.cc_status_req_rsp.cc_id);
            break;
         }
         ast_cc_agent_status_response(agent->core_id,
            subcmd->u.cc_status_req_rsp.status ? AST_DEVICE_INUSE
            : AST_DEVICE_NOT_INUSE);
         ao2_ref(agent, -1);
         break;
#endif   /* defined(HAVE_PRI_CCSS) */
#if defined(HAVE_PRI_CCSS)
      case PRI_SUBCMD_CC_STATUS:
         agent = sig_pri_find_cc_agent_by_cc_id(pri, subcmd->u.cc_status.cc_id);
         if (!agent) {
            pri_cc_cancel(pri->pri, subcmd->u.cc_status.cc_id);
            break;
         }
         if (subcmd->u.cc_status.status) {
            ast_cc_agent_caller_busy(agent->core_id, "%s agent caller is busy",
               sig_pri_cc_type_name);
         } else {
            ast_cc_agent_caller_available(agent->core_id,
               "%s agent caller is available", sig_pri_cc_type_name);
         }
         ao2_ref(agent, -1);
         break;
#endif   /* defined(HAVE_PRI_CCSS) */
#if defined(HAVE_PRI_CCSS)
      case PRI_SUBCMD_CC_CANCEL:
         sig_pri_cc_link_canceled(pri, subcmd->u.cc_cancel.cc_id,
            subcmd->u.cc_cancel.is_agent);
         break;
#endif   /* defined(HAVE_PRI_CCSS) */
#if defined(HAVE_PRI_CCSS)
      case PRI_SUBCMD_CC_STOP_ALERTING:
         monitor = sig_pri_find_cc_monitor_by_cc_id(pri,
            subcmd->u.cc_stop_alerting.cc_id);
         if (!monitor) {
            pri_cc_cancel(pri->pri, subcmd->u.cc_stop_alerting.cc_id);
            break;
         }
         ast_cc_monitor_stop_ringing(monitor->core_id);
         ao2_ref(monitor, -1);
         break;
#endif   /* defined(HAVE_PRI_CCSS) */
#if defined(HAVE_PRI_AOC_EVENTS)
      case PRI_SUBCMD_AOC_E:
         /* Queue AST_CONTROL_AOC frame */
         sig_pri_aoc_e_from_pri(&subcmd->u.aoc_e, NULL, 0);
         break;
#endif   /* defined(HAVE_PRI_AOC_EVENTS) */
      default:
         ast_debug(2, "Span %d: Unknown CIS subcommand(%d) in %s event.\n", pri->span,
            subcmd->cmd, pri_event2str(event_id));
         break;
      }
   }
}

#if defined(HAVE_PRI_AOC_EVENTS)
/*!
 * \internal
 * \brief detect if AOC-S subcmd is present.
 * \since 1.8
 *
 * \param subcmds Subcommands to process if any. (Could be NULL).
 *
 * \note Knowing whether or not an AOC-E subcmd is present on certain
 * PRI hangup events is necessary to determine what method to use to hangup
 * the ast_channel.  If an AOC-E subcmd just came in, then a new AOC-E was queued
 * on the ast_channel.  If a soft hangup is used, the AOC-E msg will never make it
 * across the bridge, but if a AST_CONTROL_HANGUP frame is queued behind it
 * we can ensure the AOC-E frame makes it to it's destination before the hangup
 * frame is read.
 *
 *
 * \retval 0 AOC-E is not present in subcmd list
 * \retval 1 AOC-E is present in subcmd list
 */
static int detect_aoc_e_subcmd(const struct pri_subcommands *subcmds)
{
   int i;

   if (!subcmds) {
      return 0;
   }
   for (i = 0; i < subcmds->counter_subcmd; ++i) {
      const struct pri_subcommand *subcmd = &subcmds->subcmd[i];
      if (subcmd->cmd == PRI_SUBCMD_AOC_E) {
         return 1;
      }
   }
   return 0;
}
#endif   /* defined(HAVE_PRI_AOC_EVENTS) */

/*!
 * \internal
 * \brief Handle the call associated PRI subcommand events.
 * \since 1.8
 *
 * \param pri PRI span control structure.
 * \param chanpos Channel position in the span.
 * \param event_id PRI event id
 * \param subcmds Subcommands to process if any. (Could be NULL).
 * \param call_rsp libpri opaque call structure to send any responses toward.
 * Could be NULL either because it is not available or the call is for the
 * dummy call reference.  However, this should not be NULL in the cases that
 * need to use the pointer to send a response message back.
 *
 * \note Assumes the pri->lock is already obtained.
 * \note Assumes the sig_pri_lock_private(pri->pvts[chanpos]) is already obtained.
 *
 * \return Nothing
 */
static void sig_pri_handle_subcmds(struct sig_pri_span *pri, int chanpos, int event_id,
   const struct pri_subcommands *subcmds, q931_call *call_rsp)
{
   int index;
   struct ast_channel *owner;
   struct ast_party_redirecting ast_redirecting;
#if defined(HAVE_PRI_TRANSFER)
   struct xfer_rsp_data xfer_rsp;
#endif   /* defined(HAVE_PRI_TRANSFER) */

   if (!subcmds) {
      return;
   }
   for (index = 0; index < subcmds->counter_subcmd; ++index) {
      const struct pri_subcommand *subcmd = &subcmds->subcmd[index];

      switch (subcmd->cmd) {
      case PRI_SUBCMD_CONNECTED_LINE:
         sig_pri_lock_owner(pri, chanpos);
         owner = pri->pvts[chanpos]->owner;
         if (owner) {
            struct ast_party_connected_line ast_connected;
            int caller_id_update;

            /* Extract the connected line information */
            ast_party_connected_line_init(&ast_connected);
            sig_pri_party_id_convert(&ast_connected.id, &subcmd->u.connected_line.id,
               pri);
            ast_connected.id.tag = ast_strdup(pri->pvts[chanpos]->user_tag);

            caller_id_update = 0;
            if (ast_connected.id.name.str) {
               /* Save name for Caller-ID update */
               ast_copy_string(pri->pvts[chanpos]->cid_name,
                  ast_connected.id.name.str, sizeof(pri->pvts[chanpos]->cid_name));
               caller_id_update = 1;
            }
            if (ast_connected.id.number.str) {
               /* Save number for Caller-ID update */
               ast_copy_string(pri->pvts[chanpos]->cid_num,
                  ast_connected.id.number.str, sizeof(pri->pvts[chanpos]->cid_num));
               pri->pvts[chanpos]->cid_ton = ast_connected.id.number.plan;
               caller_id_update = 1;
            }
            ast_connected.source = AST_CONNECTED_LINE_UPDATE_SOURCE_ANSWER;

            pri->pvts[chanpos]->cid_subaddr[0] = '\0';
#if defined(HAVE_PRI_SUBADDR)
            if (ast_connected.id.subaddress.str) {
               ast_copy_string(pri->pvts[chanpos]->cid_subaddr,
                  ast_connected.id.subaddress.str,
                  sizeof(pri->pvts[chanpos]->cid_subaddr));
               caller_id_update = 1;
            }
#endif   /* defined(HAVE_PRI_SUBADDR) */
            if (caller_id_update) {
               struct ast_party_caller ast_caller;

               pri->pvts[chanpos]->callingpres =
                  ast_party_id_presentation(&ast_connected.id);
               sig_pri_set_caller_id(pri->pvts[chanpos]);

               ast_party_caller_set_init(&ast_caller, ast_channel_caller(owner));
               ast_caller.id = ast_connected.id;
               ast_caller.ani = ast_connected.id;
               ast_channel_set_caller_event(owner, &ast_caller, NULL);

               /* Update the connected line information on the other channel */
               if (event_id != PRI_EVENT_RING) {
                  /* This connected_line update was not from a SETUP message. */
                  ast_channel_queue_connected_line_update(owner, &ast_connected,
                     NULL);
               }
            }

            ast_party_connected_line_free(&ast_connected);
            ast_channel_unlock(owner);
         }
         break;
      case PRI_SUBCMD_REDIRECTING:
         sig_pri_lock_owner(pri, chanpos);
         owner = pri->pvts[chanpos]->owner;
         if (owner) {
            sig_pri_redirecting_convert(&ast_redirecting, &subcmd->u.redirecting,
               ast_channel_redirecting(owner), pri);
            ast_redirecting.orig.tag = ast_strdup(pri->pvts[chanpos]->user_tag);
            ast_redirecting.from.tag = ast_strdup(pri->pvts[chanpos]->user_tag);
            ast_redirecting.to.tag = ast_strdup(pri->pvts[chanpos]->user_tag);
            ast_channel_set_redirecting(owner, &ast_redirecting, NULL);
            if (event_id != PRI_EVENT_RING) {
               /* This redirection was not from a SETUP message. */

               /* Invalidate any earlier private redirecting id representations */
               ast_party_id_invalidate(&ast_redirecting.priv_orig);
               ast_party_id_invalidate(&ast_redirecting.priv_from);
               ast_party_id_invalidate(&ast_redirecting.priv_to);

               ast_channel_queue_redirecting_update(owner, &ast_redirecting, NULL);
            }
            ast_party_redirecting_free(&ast_redirecting);

            ast_channel_unlock(owner);
         }
         break;
#if defined(HAVE_PRI_CALL_REROUTING)
      case PRI_SUBCMD_REROUTING:
         sig_pri_lock_owner(pri, chanpos);
         owner = pri->pvts[chanpos]->owner;
         if (owner) {
            struct pri_party_redirecting pri_deflection;

            if (!call_rsp) {
               ast_log(LOG_WARNING,
                  "Span %d: %s tried CallRerouting/CallDeflection to '%s' without call!\n",
                  pri->span, ast_channel_name(owner), subcmd->u.rerouting.deflection.to.number.str);
               ast_channel_unlock(owner);
               break;
            }
            if (ast_strlen_zero(subcmd->u.rerouting.deflection.to.number.str)) {
               ast_log(LOG_WARNING,
                  "Span %d: %s tried CallRerouting/CallDeflection to empty number!\n",
                  pri->span, ast_channel_name(owner));
               pri_rerouting_rsp(pri->pri, call_rsp, subcmd->u.rerouting.invoke_id,
                  PRI_REROUTING_RSP_INVALID_NUMBER);
               ast_channel_unlock(owner);
               break;
            }

            ast_verb(3, "Span %d: %s is CallRerouting/CallDeflection to '%s'.\n",
               pri->span, ast_channel_name(owner), subcmd->u.rerouting.deflection.to.number.str);

            /*
             * Send back positive ACK to CallRerouting/CallDeflection.
             *
             * Note:  This call will be hungup by the core when it processes
             * the call_forward string.
             */
            pri_rerouting_rsp(pri->pri, call_rsp, subcmd->u.rerouting.invoke_id,
               PRI_REROUTING_RSP_OK_CLEAR);

            pri_deflection = subcmd->u.rerouting.deflection;

            /* Adjust the deflecting to number based upon the subscription option. */
            switch (subcmd->u.rerouting.subscription_option) {
            case 0:  /* noNotification */
            case 1:  /* notificationWithoutDivertedToNr */
               /* Delete the number because the far end is not supposed to see it. */
               pri_deflection.to.number.presentation =
                  PRI_PRES_RESTRICTED | PRI_PRES_USER_NUMBER_UNSCREENED;
               pri_deflection.to.number.plan =
                  (PRI_TON_UNKNOWN << 4) | PRI_NPI_E163_E164;
               pri_deflection.to.number.str[0] = '\0';
               break;
            case 2:  /* notificationWithDivertedToNr */
               break;
            case 3:  /* notApplicable */
            default:
               break;
            }
            sig_pri_redirecting_convert(&ast_redirecting, &pri_deflection,
               ast_channel_redirecting(owner), pri);
            ast_redirecting.orig.tag = ast_strdup(pri->pvts[chanpos]->user_tag);
            ast_redirecting.from.tag = ast_strdup(pri->pvts[chanpos]->user_tag);
            ast_redirecting.to.tag = ast_strdup(pri->pvts[chanpos]->user_tag);
            ast_channel_set_redirecting(owner, &ast_redirecting, NULL);
            ast_party_redirecting_free(&ast_redirecting);

            /* Request the core to forward to the new number. */
            ast_channel_call_forward_set(owner, subcmd->u.rerouting.deflection.to.number.str);

            /* Wake up the channel. */
            ast_queue_frame(owner, &ast_null_frame);

            ast_channel_unlock(owner);
         }
         break;
#endif   /* defined(HAVE_PRI_CALL_REROUTING) */
#if defined(HAVE_PRI_CCSS)
      case PRI_SUBCMD_CC_AVAILABLE:
         sig_pri_lock_owner(pri, chanpos);
         owner = pri->pvts[chanpos]->owner;
         if (owner) {
            enum ast_cc_service_type service;

            switch (event_id) {
            case PRI_EVENT_RINGING:
               service = AST_CC_CCNR;
               break;
            case PRI_EVENT_HANGUP_REQ:
               /* We will assume that the cause was busy/congestion. */
               service = AST_CC_CCBS;
               break;
            default:
               service = AST_CC_NONE;
               break;
            }
            if (service == AST_CC_NONE
               || sig_pri_cc_available(pri, chanpos, subcmd->u.cc_available.cc_id,
               service)) {
               pri_cc_cancel(pri->pri, subcmd->u.cc_available.cc_id);
            }
            ast_channel_unlock(owner);
         } else {
            /* No asterisk channel. */
            pri_cc_cancel(pri->pri, subcmd->u.cc_available.cc_id);
         }
         break;
#endif   /* defined(HAVE_PRI_CCSS) */
#if defined(HAVE_PRI_CCSS)
      case PRI_SUBCMD_CC_CALL:
         sig_pri_lock_owner(pri, chanpos);
         owner = pri->pvts[chanpos]->owner;
         if (owner) {
            struct ast_cc_agent *agent;

            agent = sig_pri_find_cc_agent_by_cc_id(pri, subcmd->u.cc_call.cc_id);
            if (agent) {
               ast_setup_cc_recall_datastore(owner, agent->core_id);
               ast_cc_agent_set_interfaces_chanvar(owner);
               ast_cc_agent_recalling(agent->core_id,
                  "%s caller is attempting recall", sig_pri_cc_type_name);
               ao2_ref(agent, -1);
            }

            ast_channel_unlock(owner);
         }
         break;
#endif   /* defined(HAVE_PRI_CCSS) */
#if defined(HAVE_PRI_CCSS)
      case PRI_SUBCMD_CC_CANCEL:
         sig_pri_cc_link_canceled(pri, subcmd->u.cc_cancel.cc_id,
            subcmd->u.cc_cancel.is_agent);
         break;
#endif   /* defined(HAVE_PRI_CCSS) */
#if defined(HAVE_PRI_TRANSFER)
      case PRI_SUBCMD_TRANSFER_CALL:
         if (!call_rsp) {
            /* Should never happen. */
            ast_log(LOG_ERROR,
               "Call transfer subcommand without call to send response!\n");
            break;
         }

         sig_pri_unlock_private(pri->pvts[chanpos]);
         xfer_rsp.pri = pri;
         xfer_rsp.call = call_rsp;
         xfer_rsp.invoke_id = subcmd->u.transfer.invoke_id;
         sig_pri_attempt_transfer(pri,
            subcmd->u.transfer.call_1, subcmd->u.transfer.is_call_1_held,
            subcmd->u.transfer.call_2, subcmd->u.transfer.is_call_2_held,
            sig_pri_transfer_rsp, &xfer_rsp);
         sig_pri_lock_private(pri->pvts[chanpos]);
         break;
#endif   /* defined(HAVE_PRI_TRANSFER) */
#if defined(HAVE_PRI_AOC_EVENTS)
      case PRI_SUBCMD_AOC_S:
         sig_pri_lock_owner(pri, chanpos);
         owner = pri->pvts[chanpos]->owner;
         if (owner) {
            sig_pri_aoc_s_from_pri(&subcmd->u.aoc_s, owner,
               (pri->aoc_passthrough_flag & SIG_PRI_AOC_GRANT_S));
            ast_channel_unlock(owner);
         }
         break;
#endif   /* defined(HAVE_PRI_AOC_EVENTS) */
#if defined(HAVE_PRI_AOC_EVENTS)
      case PRI_SUBCMD_AOC_D:
         sig_pri_lock_owner(pri, chanpos);
         owner = pri->pvts[chanpos]->owner;
         if (owner) {
            /* Queue AST_CONTROL_AOC frame on channel */
            sig_pri_aoc_d_from_pri(&subcmd->u.aoc_d, owner,
               (pri->aoc_passthrough_flag & SIG_PRI_AOC_GRANT_D));
            ast_channel_unlock(owner);
         }
         break;
#endif   /* defined(HAVE_PRI_AOC_EVENTS) */
#if defined(HAVE_PRI_AOC_EVENTS)
      case PRI_SUBCMD_AOC_E:
         sig_pri_lock_owner(pri, chanpos);
         owner = pri->pvts[chanpos]->owner;
         /* Queue AST_CONTROL_AOC frame */
         sig_pri_aoc_e_from_pri(&subcmd->u.aoc_e, owner,
            (pri->aoc_passthrough_flag & SIG_PRI_AOC_GRANT_E));
         if (owner) {
            ast_channel_unlock(owner);
         }
         break;
#endif   /* defined(HAVE_PRI_AOC_EVENTS) */
#if defined(HAVE_PRI_AOC_EVENTS)
      case PRI_SUBCMD_AOC_CHARGING_REQ:
         sig_pri_lock_owner(pri, chanpos);
         owner = pri->pvts[chanpos]->owner;
         if (owner) {
            sig_pri_aoc_request_from_pri(&subcmd->u.aoc_request, pri->pvts[chanpos],
               call_rsp);
            ast_channel_unlock(owner);
         }
         break;
#endif   /* defined(HAVE_PRI_AOC_EVENTS) */
#if defined(HAVE_PRI_AOC_EVENTS)
      case PRI_SUBCMD_AOC_CHARGING_REQ_RSP:
         /*
          * An AOC request response may contain an AOC-S rate list.
          * If this is the case handle this just like we
          * would an incoming AOC-S msg.
          */
         if (subcmd->u.aoc_request_response.valid_aoc_s) {
            sig_pri_lock_owner(pri, chanpos);
            owner = pri->pvts[chanpos]->owner;
            if (owner) {
               sig_pri_aoc_s_from_pri(&subcmd->u.aoc_request_response.aoc_s, owner,
                  (pri->aoc_passthrough_flag & SIG_PRI_AOC_GRANT_S));
               ast_channel_unlock(owner);
            }
         }
         break;
#endif   /* defined(HAVE_PRI_AOC_EVENTS) */
#if defined(HAVE_PRI_MCID)
      case PRI_SUBCMD_MCID_REQ:
         sig_pri_lock_owner(pri, chanpos);
         owner = pri->pvts[chanpos]->owner;
         sig_pri_mcid_event(pri, &subcmd->u.mcid_req, owner);
         if (owner) {
            ast_channel_unlock(owner);
         }
         break;
#endif   /* defined(HAVE_PRI_MCID) */
#if defined(HAVE_PRI_MCID)
      case PRI_SUBCMD_MCID_RSP:
         /* Ignore for now. */
         break;
#endif   /* defined(HAVE_PRI_MCID) */
#if defined(HAVE_PRI_DISPLAY_TEXT)
      case PRI_SUBCMD_DISPLAY_TEXT:
         if (event_id != PRI_EVENT_RING) {
            /*
             * This display text was not from a SETUP message.  We can do
             * something with this display text string.
             */
            sig_pri_lock_owner(pri, chanpos);
            owner = pri->pvts[chanpos]->owner;
            if (owner) {
               struct ast_frame f;

               /* Pass the display text to the peer channel. */
               memset(&f, 0, sizeof(f));
               f.frametype = AST_FRAME_TEXT;
               f.subclass.integer = 0;
               f.offset = 0;
               f.data.ptr = &subcmd->u.display.text;
               f.datalen = subcmd->u.display.length + 1;
               ast_queue_frame(owner, &f);
               ast_channel_unlock(owner);
            }
         }
         break;
#endif   /* defined(HAVE_PRI_DISPLAY_TEXT) */
      default:
         ast_debug(2, "Span %d: Unknown call subcommand(%d) in %s event.\n",
            pri->span, subcmd->cmd, pri_event2str(event_id));
         break;
      }
   }
}

/*!
 * \internal
 * \brief Convert the MOH state to string.
 * \since 10.0
 *
 * \param state MOH state to process.
 *
 * \return String version of MOH state.
 */
static const char *sig_pri_moh_state_str(enum sig_pri_moh_state state)
{
   const char *str;

   str = "Unknown";
   switch (state) {
   case SIG_PRI_MOH_STATE_IDLE:
      str = "SIG_PRI_MOH_STATE_IDLE";
      break;
   case SIG_PRI_MOH_STATE_NOTIFY:
      str = "SIG_PRI_MOH_STATE_NOTIFY";
      break;
   case SIG_PRI_MOH_STATE_MOH:
      str = "SIG_PRI_MOH_STATE_MOH";
      break;
#if defined(HAVE_PRI_CALL_HOLD)
   case SIG_PRI_MOH_STATE_HOLD_REQ:
      str = "SIG_PRI_MOH_STATE_HOLD_REQ";
      break;
   case SIG_PRI_MOH_STATE_PEND_UNHOLD:
      str = "SIG_PRI_MOH_STATE_PEND_UNHOLD";
      break;
   case SIG_PRI_MOH_STATE_HOLD:
      str = "SIG_PRI_MOH_STATE_HOLD";
      break;
   case SIG_PRI_MOH_STATE_RETRIEVE_REQ:
      str = "SIG_PRI_MOH_STATE_RETRIEVE_REQ";
      break;
   case SIG_PRI_MOH_STATE_PEND_HOLD:
      str = "SIG_PRI_MOH_STATE_PEND_HOLD";
      break;
   case SIG_PRI_MOH_STATE_RETRIEVE_FAIL:
      str = "SIG_PRI_MOH_STATE_RETRIEVE_FAIL";
      break;
#endif   /* defined(HAVE_PRI_CALL_HOLD) */
   case SIG_PRI_MOH_STATE_NUM:
      /* Not a real state. */
      break;
   }
   return str;
}

/*!
 * \internal
 * \brief Convert the MOH event to string.
 * \since 10.0
 *
 * \param event MOH event to process.
 *
 * \return String version of MOH event.
 */
static const char *sig_pri_moh_event_str(enum sig_pri_moh_event event)
{
   const char *str;

   str = "Unknown";
   switch (event) {
   case SIG_PRI_MOH_EVENT_RESET:
      str = "SIG_PRI_MOH_EVENT_RESET";
      break;
   case SIG_PRI_MOH_EVENT_HOLD:
      str = "SIG_PRI_MOH_EVENT_HOLD";
      break;
   case SIG_PRI_MOH_EVENT_UNHOLD:
      str = "SIG_PRI_MOH_EVENT_UNHOLD";
      break;
#if defined(HAVE_PRI_CALL_HOLD)
   case SIG_PRI_MOH_EVENT_HOLD_ACK:
      str = "SIG_PRI_MOH_EVENT_HOLD_ACK";
      break;
   case SIG_PRI_MOH_EVENT_HOLD_REJ:
      str = "SIG_PRI_MOH_EVENT_HOLD_REJ";
      break;
   case SIG_PRI_MOH_EVENT_RETRIEVE_ACK:
      str = "SIG_PRI_MOH_EVENT_RETRIEVE_ACK";
      break;
   case SIG_PRI_MOH_EVENT_RETRIEVE_REJ:
      str = "SIG_PRI_MOH_EVENT_RETRIEVE_REJ";
      break;
   case SIG_PRI_MOH_EVENT_REMOTE_RETRIEVE_ACK:
      str = "SIG_PRI_MOH_EVENT_REMOTE_RETRIEVE_ACK";
      break;
#endif   /* defined(HAVE_PRI_CALL_HOLD) */
   case SIG_PRI_MOH_EVENT_NUM:
      /* Not a real event. */
      break;
   }
   return str;
}

#if defined(HAVE_PRI_CALL_HOLD)
/*!
 * \internal
 * \brief Retrieve a call that was placed on hold by the HOLD message.
 * \since 10.0
 *
 * \param pvt Channel private control structure.
 * 
 * \note Assumes the pvt->pri->lock is already obtained.
 * \note Assumes the sig_pri_lock_private(pvt) is already obtained.
 *
 * \return Next MOH state
 */
static enum sig_pri_moh_state sig_pri_moh_retrieve_call(struct sig_pri_chan *pvt)
{
   int chanpos;
   int channel;

   if (pvt->pri->nodetype == PRI_NETWORK) {
      /* Find an available channel to propose */
      chanpos = pri_find_empty_chan(pvt->pri, 1);
      if (chanpos < 0) {
         /* No channels available. */
         return SIG_PRI_MOH_STATE_RETRIEVE_FAIL;
      }
      channel = PVT_TO_CHANNEL(pvt->pri->pvts[chanpos]);

      /*
       * We cannot occupy or reserve this channel at this time because
       * the retrieve may fail or we could have a RETRIEVE collision.
       */
   } else {
      /* Let the network pick the channel. */
      channel = 0;
   }

   if (pri_retrieve(pvt->pri->pri, pvt->call, channel)) {
      return SIG_PRI_MOH_STATE_RETRIEVE_FAIL;
   }
   return SIG_PRI_MOH_STATE_RETRIEVE_REQ;
}
#endif   /* defined(HAVE_PRI_CALL_HOLD) */

/*!
 * \internal
 * \brief MOH FSM state idle.
 * \since 10.0
 *
 * \param chan Channel to post event to (Usually pvt->owner)
 * \param pvt Channel private control structure.
 * \param event MOH event to process.
 * 
 * \note Assumes the pvt->pri->lock is already obtained.
 * \note Assumes the sig_pri_lock_private(pvt) is already obtained.
 *
 * \return Next MOH state
 */
static enum sig_pri_moh_state sig_pri_moh_fsm_idle(struct ast_channel *chan, struct sig_pri_chan *pvt, enum sig_pri_moh_event event)
{
   enum sig_pri_moh_state next_state;

   next_state = pvt->moh_state;
   switch (event) {
   case SIG_PRI_MOH_EVENT_HOLD:
      if (!strcasecmp(pvt->mohinterpret, "passthrough")) {
         /*
          * This config setting is deprecated.
          * The old way did not send MOH just in case the notification was ignored.
          */
         pri_notify(pvt->pri->pri, pvt->call, pvt->prioffset, PRI_NOTIFY_REMOTE_HOLD);
         next_state = SIG_PRI_MOH_STATE_NOTIFY;
         break;
      }

      switch (pvt->pri->moh_signaling) {
      default:
      case SIG_PRI_MOH_SIGNALING_MOH:
         ast_moh_start(chan, pvt->moh_suggested, pvt->mohinterpret);
         next_state = SIG_PRI_MOH_STATE_MOH;
         break;
      case SIG_PRI_MOH_SIGNALING_NOTIFY:
         /* Send MOH anyway in case the far end does not interpret the notification. */
         ast_moh_start(chan, pvt->moh_suggested, pvt->mohinterpret);

         pri_notify(pvt->pri->pri, pvt->call, pvt->prioffset, PRI_NOTIFY_REMOTE_HOLD);
         next_state = SIG_PRI_MOH_STATE_NOTIFY;
         break;
#if defined(HAVE_PRI_CALL_HOLD)
      case SIG_PRI_MOH_SIGNALING_HOLD:
         if (pri_hold(pvt->pri->pri, pvt->call)) {
            /* Fall back to MOH instead */
            ast_moh_start(chan, pvt->moh_suggested, pvt->mohinterpret);
            next_state = SIG_PRI_MOH_STATE_MOH;
         } else {
            next_state = SIG_PRI_MOH_STATE_HOLD_REQ;
         }
         break;
#endif   /* defined(HAVE_PRI_CALL_HOLD) */
      }
      break;
   default:
      break;
   }
   pvt->moh_state = next_state;
   return next_state;
}

/*!
 * \internal
 * \brief MOH FSM state notify remote party.
 * \since 10.0
 *
 * \param chan Channel to post event to (Usually pvt->owner)
 * \param pvt Channel private control structure.
 * \param event MOH event to process.
 * 
 * \note Assumes the pvt->pri->lock is already obtained.
 * \note Assumes the sig_pri_lock_private(pvt) is already obtained.
 *
 * \return Next MOH state
 */
static enum sig_pri_moh_state sig_pri_moh_fsm_notify(struct ast_channel *chan, struct sig_pri_chan *pvt, enum sig_pri_moh_event event)
{
   enum sig_pri_moh_state next_state;

   next_state = pvt->moh_state;
   switch (event) {
   case SIG_PRI_MOH_EVENT_HOLD:
      if (strcasecmp(pvt->mohinterpret, "passthrough")) {
         /* Restart MOH in case it was stopped by other means. */
         ast_moh_start(chan, pvt->moh_suggested, pvt->mohinterpret);
      }
      break;
   case SIG_PRI_MOH_EVENT_UNHOLD:
      pri_notify(pvt->pri->pri, pvt->call, pvt->prioffset, PRI_NOTIFY_REMOTE_RETRIEVAL);
      /* Fall through */
   case SIG_PRI_MOH_EVENT_RESET:
      ast_moh_stop(chan);
      next_state = SIG_PRI_MOH_STATE_IDLE;
      break;
   default:
      break;
   }
   pvt->moh_state = next_state;
   return next_state;
}

/*!
 * \internal
 * \brief MOH FSM state generate moh.
 * \since 10.0
 *
 * \param chan Channel to post event to (Usually pvt->owner)
 * \param pvt Channel private control structure.
 * \param event MOH event to process.
 * 
 * \note Assumes the pvt->pri->lock is already obtained.
 * \note Assumes the sig_pri_lock_private(pvt) is already obtained.
 *
 * \return Next MOH state
 */
static enum sig_pri_moh_state sig_pri_moh_fsm_moh(struct ast_channel *chan, struct sig_pri_chan *pvt, enum sig_pri_moh_event event)
{
   enum sig_pri_moh_state next_state;

   next_state = pvt->moh_state;
   switch (event) {
   case SIG_PRI_MOH_EVENT_HOLD:
      /* Restart MOH in case it was stopped by other means. */
      ast_moh_start(chan, pvt->moh_suggested, pvt->mohinterpret);
      break;
   case SIG_PRI_MOH_EVENT_RESET:
   case SIG_PRI_MOH_EVENT_UNHOLD:
      ast_moh_stop(chan);
      next_state = SIG_PRI_MOH_STATE_IDLE;
      break;
   default:
      break;
   }
   pvt->moh_state = next_state;
   return next_state;
}

#if defined(HAVE_PRI_CALL_HOLD)
/*!
 * \internal
 * \brief MOH FSM state hold requested.
 * \since 10.0
 *
 * \param chan Channel to post event to (Usually pvt->owner)
 * \param pvt Channel private control structure.
 * \param event MOH event to process.
 * 
 * \note Assumes the pvt->pri->lock is already obtained.
 * \note Assumes the sig_pri_lock_private(pvt) is already obtained.
 *
 * \return Next MOH state
 */
static enum sig_pri_moh_state sig_pri_moh_fsm_hold_req(struct ast_channel *chan, struct sig_pri_chan *pvt, enum sig_pri_moh_event event)
{
   enum sig_pri_moh_state next_state;

   next_state = pvt->moh_state;
   switch (event) {
   case SIG_PRI_MOH_EVENT_RESET:
      next_state = SIG_PRI_MOH_STATE_IDLE;
      break;
   case SIG_PRI_MOH_EVENT_UNHOLD:
      next_state = SIG_PRI_MOH_STATE_PEND_UNHOLD;
      break;
   case SIG_PRI_MOH_EVENT_HOLD_REJ:
      /* Fall back to MOH */
      if (chan) {
         ast_moh_start(chan, pvt->moh_suggested, pvt->mohinterpret);
      }
      next_state = SIG_PRI_MOH_STATE_MOH;
      break;
   case SIG_PRI_MOH_EVENT_HOLD_ACK:
      next_state = SIG_PRI_MOH_STATE_HOLD;
      break;
   default:
      break;
   }
   pvt->moh_state = next_state;
   return next_state;
}
#endif   /* defined(HAVE_PRI_CALL_HOLD) */

#if defined(HAVE_PRI_CALL_HOLD)
/*!
 * \internal
 * \brief MOH FSM state hold requested with pending unhold.
 * \since 10.0
 *
 * \param chan Channel to post event to (Usually pvt->owner)
 * \param pvt Channel private control structure.
 * \param event MOH event to process.
 * 
 * \note Assumes the pvt->pri->lock is already obtained.
 * \note Assumes the sig_pri_lock_private(pvt) is already obtained.
 *
 * \return Next MOH state
 */
static enum sig_pri_moh_state sig_pri_moh_fsm_pend_unhold(struct ast_channel *chan, struct sig_pri_chan *pvt, enum sig_pri_moh_event event)
{
   enum sig_pri_moh_state next_state;

   next_state = pvt->moh_state;
   switch (event) {
   case SIG_PRI_MOH_EVENT_RESET:
      next_state = SIG_PRI_MOH_STATE_IDLE;
      break;
   case SIG_PRI_MOH_EVENT_HOLD:
      next_state = SIG_PRI_MOH_STATE_HOLD_REQ;
      break;
   case SIG_PRI_MOH_EVENT_HOLD_REJ:
      next_state = SIG_PRI_MOH_STATE_IDLE;
      break;
   case SIG_PRI_MOH_EVENT_HOLD_ACK:
      next_state = sig_pri_moh_retrieve_call(pvt);
      break;
   default:
      break;
   }
   pvt->moh_state = next_state;
   return next_state;
}
#endif   /* defined(HAVE_PRI_CALL_HOLD) */

#if defined(HAVE_PRI_CALL_HOLD)
/*!
 * \internal
 * \brief MOH FSM state hold.
 * \since 10.0
 *
 * \param chan Channel to post event to (Usually pvt->owner)
 * \param pvt Channel private control structure.
 * \param event MOH event to process.
 * 
 * \note Assumes the pvt->pri->lock is already obtained.
 * \note Assumes the sig_pri_lock_private(pvt) is already obtained.
 *
 * \return Next MOH state
 */
static enum sig_pri_moh_state sig_pri_moh_fsm_hold(struct ast_channel *chan, struct sig_pri_chan *pvt, enum sig_pri_moh_event event)
{
   enum sig_pri_moh_state next_state;

   next_state = pvt->moh_state;
   switch (event) {
   case SIG_PRI_MOH_EVENT_RESET:
      next_state = SIG_PRI_MOH_STATE_IDLE;
      break;
   case SIG_PRI_MOH_EVENT_UNHOLD:
      next_state = sig_pri_moh_retrieve_call(pvt);
      break;
   case SIG_PRI_MOH_EVENT_REMOTE_RETRIEVE_ACK:
      /* Fall back to MOH */
      if (chan) {
         ast_moh_start(chan, pvt->moh_suggested, pvt->mohinterpret);
      }
      next_state = SIG_PRI_MOH_STATE_MOH;
      break;
   default:
      break;
   }
   pvt->moh_state = next_state;
   return next_state;
}
#endif   /* defined(HAVE_PRI_CALL_HOLD) */

#if defined(HAVE_PRI_CALL_HOLD)
/*!
 * \internal
 * \brief MOH FSM state retrieve requested.
 * \since 10.0
 *
 * \param chan Channel to post event to (Usually pvt->owner)
 * \param pvt Channel private control structure.
 * \param event MOH event to process.
 * 
 * \note Assumes the pvt->pri->lock is already obtained.
 * \note Assumes the sig_pri_lock_private(pvt) is already obtained.
 *
 * \return Next MOH state
 */
static enum sig_pri_moh_state sig_pri_moh_fsm_retrieve_req(struct ast_channel *chan, struct sig_pri_chan *pvt, enum sig_pri_moh_event event)
{
   enum sig_pri_moh_state next_state;

   next_state = pvt->moh_state;
   switch (event) {
   case SIG_PRI_MOH_EVENT_RESET:
      next_state = SIG_PRI_MOH_STATE_IDLE;
      break;
   case SIG_PRI_MOH_EVENT_HOLD:
      next_state = SIG_PRI_MOH_STATE_PEND_HOLD;
      break;
   case SIG_PRI_MOH_EVENT_RETRIEVE_ACK:
   case SIG_PRI_MOH_EVENT_REMOTE_RETRIEVE_ACK:
      next_state = SIG_PRI_MOH_STATE_IDLE;
      break;
   case SIG_PRI_MOH_EVENT_RETRIEVE_REJ:
      next_state = SIG_PRI_MOH_STATE_RETRIEVE_FAIL;
      break;
   default:
      break;
   }
   pvt->moh_state = next_state;
   return next_state;
}
#endif   /* defined(HAVE_PRI_CALL_HOLD) */

#if defined(HAVE_PRI_CALL_HOLD)
/*!
 * \internal
 * \brief MOH FSM state retrieve requested with pending hold.
 * \since 10.0
 *
 * \param chan Channel to post event to (Usually pvt->owner)
 * \param pvt Channel private control structure.
 * \param event MOH event to process.
 * 
 * \note Assumes the pvt->pri->lock is already obtained.
 * \note Assumes the sig_pri_lock_private(pvt) is already obtained.
 *
 * \return Next MOH state
 */
static enum sig_pri_moh_state sig_pri_moh_fsm_pend_hold(struct ast_channel *chan, struct sig_pri_chan *pvt, enum sig_pri_moh_event event)
{
   enum sig_pri_moh_state next_state;

   next_state = pvt->moh_state;
   switch (event) {
   case SIG_PRI_MOH_EVENT_RESET:
      next_state = SIG_PRI_MOH_STATE_IDLE;
      break;
   case SIG_PRI_MOH_EVENT_UNHOLD:
      next_state = SIG_PRI_MOH_STATE_RETRIEVE_REQ;
      break;
   case SIG_PRI_MOH_EVENT_RETRIEVE_ACK:
   case SIG_PRI_MOH_EVENT_REMOTE_RETRIEVE_ACK:
      /*
       * Successfully came off of hold.  Now we can reinterpret the
       * MOH signaling option to handle the pending HOLD request.
       */
      switch (pvt->pri->moh_signaling) {
      default:
      case SIG_PRI_MOH_SIGNALING_MOH:
         if (chan) {
            ast_moh_start(chan, pvt->moh_suggested, pvt->mohinterpret);
         }
         next_state = SIG_PRI_MOH_STATE_MOH;
         break;
      case SIG_PRI_MOH_SIGNALING_NOTIFY:
         /* Send MOH anyway in case the far end does not interpret the notification. */
         if (chan) {
            ast_moh_start(chan, pvt->moh_suggested, pvt->mohinterpret);
         }

         pri_notify(pvt->pri->pri, pvt->call, pvt->prioffset, PRI_NOTIFY_REMOTE_HOLD);
         next_state = SIG_PRI_MOH_STATE_NOTIFY;
         break;
      case SIG_PRI_MOH_SIGNALING_HOLD:
         if (pri_hold(pvt->pri->pri, pvt->call)) {
            /* Fall back to MOH instead */
            if (chan) {
               ast_moh_start(chan, pvt->moh_suggested, pvt->mohinterpret);
            }
            next_state = SIG_PRI_MOH_STATE_MOH;
         } else {
            next_state = SIG_PRI_MOH_STATE_HOLD_REQ;
         }
         break;
      }
      break;
   case SIG_PRI_MOH_EVENT_RETRIEVE_REJ:
      /*
       * We cannot reinterpret the MOH signaling option because we
       * failed to come off of hold.
       */
      next_state = SIG_PRI_MOH_STATE_HOLD;
      break;
   default:
      break;
   }
   pvt->moh_state = next_state;
   return next_state;
}
#endif   /* defined(HAVE_PRI_CALL_HOLD) */

#if defined(HAVE_PRI_CALL_HOLD)
/*!
 * \internal
 * \brief MOH FSM state retrieve failed.
 * \since 10.0
 *
 * \param chan Channel to post event to (Usually pvt->owner)
 * \param pvt Channel private control structure.
 * \param event MOH event to process.
 * 
 * \note Assumes the pvt->pri->lock is already obtained.
 * \note Assumes the sig_pri_lock_private(pvt) is already obtained.
 *
 * \return Next MOH state
 */
static enum sig_pri_moh_state sig_pri_moh_fsm_retrieve_fail(struct ast_channel *chan, struct sig_pri_chan *pvt, enum sig_pri_moh_event event)
{
   enum sig_pri_moh_state next_state;

   next_state = pvt->moh_state;
   switch (event) {
   case SIG_PRI_MOH_EVENT_RESET:
      next_state = SIG_PRI_MOH_STATE_IDLE;
      break;
   case SIG_PRI_MOH_EVENT_HOLD:
      next_state = SIG_PRI_MOH_STATE_HOLD;
      break;
   case SIG_PRI_MOH_EVENT_UNHOLD:
      next_state = sig_pri_moh_retrieve_call(pvt);
      break;
   case SIG_PRI_MOH_EVENT_REMOTE_RETRIEVE_ACK:
      next_state = SIG_PRI_MOH_STATE_IDLE;
      break;
   default:
      break;
   }
   pvt->moh_state = next_state;
   return next_state;
}
#endif   /* defined(HAVE_PRI_CALL_HOLD) */

/*!
 * \internal
 * \brief MOH FSM state function type.
 * \since 10.0
 *
 * \param chan Channel to post event to (Usually pvt->owner)
 * \param pvt Channel private control structure.
 * \param event MOH event to process.
 * 
 * \note Assumes the pvt->pri->lock is already obtained.
 * \note Assumes the sig_pri_lock_private(pvt) is already obtained.
 *
 * \return Next MOH state
 */
typedef enum sig_pri_moh_state (*sig_pri_moh_fsm_state)(struct ast_channel *chan, struct sig_pri_chan *pvt, enum sig_pri_moh_event event);

/*! MOH FSM state table. */
static const sig_pri_moh_fsm_state sig_pri_moh_fsm[SIG_PRI_MOH_STATE_NUM] = {
/* *INDENT-OFF* */
   [SIG_PRI_MOH_STATE_IDLE] = sig_pri_moh_fsm_idle,
   [SIG_PRI_MOH_STATE_NOTIFY] = sig_pri_moh_fsm_notify,
   [SIG_PRI_MOH_STATE_MOH] = sig_pri_moh_fsm_moh,
#if defined(HAVE_PRI_CALL_HOLD)
   [SIG_PRI_MOH_STATE_HOLD_REQ] = sig_pri_moh_fsm_hold_req,
   [SIG_PRI_MOH_STATE_PEND_UNHOLD] = sig_pri_moh_fsm_pend_unhold,
   [SIG_PRI_MOH_STATE_HOLD] = sig_pri_moh_fsm_hold,
   [SIG_PRI_MOH_STATE_RETRIEVE_REQ] = sig_pri_moh_fsm_retrieve_req,
   [SIG_PRI_MOH_STATE_PEND_HOLD] = sig_pri_moh_fsm_pend_hold,
   [SIG_PRI_MOH_STATE_RETRIEVE_FAIL] = sig_pri_moh_fsm_retrieve_fail,
#endif   /* defined(HAVE_PRI_CALL_HOLD) */
/* *INDENT-ON* */
};

/*!
 * \internal
 * \brief Send an event to the MOH FSM.
 * \since 10.0
 *
 * \param chan Channel to post event to (Usually pvt->owner)
 * \param pvt Channel private control structure.
 * \param event MOH event to process.
 * 
 * \note Assumes the pvt->pri->lock is already obtained.
 * \note Assumes the sig_pri_lock_private(pvt) is already obtained.
 *
 * \return Nothing
 */
static void sig_pri_moh_fsm_event(struct ast_channel *chan, struct sig_pri_chan *pvt, enum sig_pri_moh_event event)
{
   enum sig_pri_moh_state orig_state;
   enum sig_pri_moh_state next_state;
   const char *chan_name;

   if (chan) {
      chan_name = ast_strdupa(ast_channel_name(chan));
   } else {
      chan_name = "Unknown";
   }
   orig_state = pvt->moh_state;
   ast_debug(2, "Channel '%s' MOH-Event: %s in state %s\n", chan_name,
      sig_pri_moh_event_str(event), sig_pri_moh_state_str(orig_state));
   if (orig_state < SIG_PRI_MOH_STATE_IDLE || SIG_PRI_MOH_STATE_NUM <= orig_state
      || !sig_pri_moh_fsm[orig_state]) {
      /* Programming error: State not implemented. */
      ast_log(LOG_ERROR, "MOH state not implemented: %s(%d)\n",
         sig_pri_moh_state_str(orig_state), orig_state);
      return;
   }
   /* Execute the state. */
   next_state = sig_pri_moh_fsm[orig_state](chan, pvt, event);
   ast_debug(2, "Channel '%s'  MOH-Next-State: %s\n", chan_name,
      (orig_state == next_state) ? "$" : sig_pri_moh_state_str(next_state));
}

#if defined(HAVE_PRI_CALL_HOLD)
/*!
 * \internal
 * \brief Post an AMI hold event.
 * \since 10.0
 *
 * \param chan Channel to post event to
 * \param is_held TRUE if the call was placed on hold.
 *
 * \return Nothing
 */
static void sig_pri_ami_hold_event(struct ast_channel *chan, int is_held)
{
   /*** DOCUMENTATION
      <managerEventInstance>
         <synopsis>Raised when a PRI channel is put on Hold.</synopsis>
         <syntax>
            <parameter name="Status">
               <enumlist>
                  <enum name="On"/>
                  <enum name="Off"/>
               </enumlist>
            </parameter>
         </syntax>
      </managerEventInstance>
   ***/
   ast_manager_event(chan, EVENT_FLAG_CALL, "Hold",
      "Status: %s\r\n"
      "Channel: %s\r\n"
      "Uniqueid: %s\r\n",
      is_held ? "On" : "Off",
      ast_channel_name(chan),
      ast_channel_uniqueid(chan));
}
#endif   /* defined(HAVE_PRI_CALL_HOLD) */

/*!
 * \internal
 * \brief Set callid threadstorage for the pri_dchannel thread when a new call is created
 *
 * \return A new callid which has been bound to threadstorage. The return must be
 *         unreffed and the threadstorage should be unbound when the pri_dchannel
 *         primary loop wraps.
 */
static struct ast_callid *func_pri_dchannel_new_callid(void)
{
   struct ast_callid *callid = ast_create_callid();

   if (callid) {
      ast_callid_threadassoc_add(callid);
   }

   return callid;
}

/*!
 * \internal
 * \brief Set callid threadstorage for the pri_dchannel thread to that of an existing channel
 *
 * \param pri PRI span control structure.
 * \param chanpos channel position in the span
 *
 * \note Assumes the pri->lock is already obtained.
 * \note Assumes the sig_pri_lock_private(pri->pvts[chanpos]) is already obtained.
 *
 * \return a reference to the callid bound to the channel which has also
 *         been bound to threadstorage if it exists. If this returns non-NULL,
 *         the callid must be unreffed and the threadstorage should be unbound
 *         when the pri_dchannel primary loop wraps.
 */
static struct ast_callid *func_pri_dchannel_chanpos_callid(struct sig_pri_span *pri, int chanpos)
{
   if (chanpos < 0) {
      return NULL;
   }

   sig_pri_lock_owner(pri, chanpos);
   if (pri->pvts[chanpos]->owner) {
      struct ast_callid *callid;
      callid = ast_channel_callid(pri->pvts[chanpos]->owner);
      ast_channel_unlock(pri->pvts[chanpos]->owner);
      if (callid) {
         ast_callid_threadassoc_add(callid);
         return callid;
      }
   }

   return NULL;
}

#if defined(HAVE_PRI_CALL_HOLD)
/*!
 * \internal
 * \brief Handle the hold event from libpri.
 * \since 1.8
 *
 * \param pri PRI span control structure.
 * \param ev Hold event received.
 *
 * \note Assumes the pri->lock is already obtained.
 *
 * \retval 0 on success.
 * \retval -1 on error.
 */
static int sig_pri_handle_hold(struct sig_pri_span *pri, pri_event *ev)
{
   int retval;
   int chanpos_old;
   int chanpos_new;
   struct ast_channel *owner;
   struct ast_callid *callid = NULL;

   chanpos_old = pri_find_principle_by_call(pri, ev->hold.call);
   if (chanpos_old < 0) {
      ast_log(LOG_WARNING, "Span %d: Received HOLD for unknown call.\n", pri->span);
      return -1;
   }
   if (pri->pvts[chanpos_old]->no_b_channel) {
      /* Call is already on hold or is call waiting call. */
      return -1;
   }

   chanpos_new = -1;

   sig_pri_lock_private(pri->pvts[chanpos_old]);
   sig_pri_lock_owner(pri, chanpos_old);
   owner = pri->pvts[chanpos_old]->owner;
   if (!owner) {
      goto done_with_private;
   }

   callid = ast_channel_callid(owner);

   if (callid) {
      ast_callid_threadassoc_add(callid);
   }

   if (pri->pvts[chanpos_old]->call_level != SIG_PRI_CALL_LEVEL_CONNECT) {
      /*
       * Make things simple.  Don't allow placing a call on hold that
       * is not connected.
       */
      goto done_with_owner;
   }
   chanpos_new = pri_find_empty_nobch(pri);
   if (chanpos_new < 0) {
      /* No hold channel available. */
      goto done_with_owner;
   }
   sig_pri_handle_subcmds(pri, chanpos_old, ev->e, ev->hold.subcmds, ev->hold.call);
   pri_queue_control(pri, chanpos_old, AST_CONTROL_HOLD);
   chanpos_new = pri_fixup_principle(pri, chanpos_new, ev->hold.call);
   if (chanpos_new < 0) {
      /* Should never happen. */
      pri_queue_control(pri, chanpos_old, AST_CONTROL_UNHOLD);
   } else {
      sig_pri_ami_hold_event(owner, 1);
   }

done_with_owner:;
   ast_channel_unlock(owner);
done_with_private:;
   sig_pri_unlock_private(pri->pvts[chanpos_old]);

   if (chanpos_new < 0) {
      retval = -1;
   } else {
      sig_pri_span_devstate_changed(pri);
      retval = 0;
   }

   if (callid) {
      ast_callid_unref(callid);
      ast_callid_threadassoc_remove();
   }

   return retval;
}
#endif   /* defined(HAVE_PRI_CALL_HOLD) */

#if defined(HAVE_PRI_CALL_HOLD)
/*!
 * \internal
 * \brief Handle the hold acknowledge event from libpri.
 * \since 10.0
 *
 * \param pri PRI span control structure.
 * \param ev Hold acknowledge event received.
 *
 * \note Assumes the pri->lock is already obtained.
 *
 * \return Nothing
 */
static void sig_pri_handle_hold_ack(struct sig_pri_span *pri, pri_event *ev)
{
   int chanpos;
   struct ast_callid *callid;

   /*
    * We were successfully put on hold by the remote party
    * so we just need to switch to a no_b_channel channel.
    */
   chanpos = pri_find_empty_nobch(pri);
   if (chanpos < 0) {
      /* Very bad news.  No hold channel available. */
      ast_log(LOG_ERROR,
         "Span %d: No hold channel available for held call that is on %d/%d\n",
         pri->span, PRI_SPAN(ev->hold_ack.channel), PRI_CHANNEL(ev->hold_ack.channel));
      sig_pri_kill_call(pri, ev->hold_ack.call, PRI_CAUSE_RESOURCE_UNAVAIL_UNSPECIFIED);
      return;
   }
   chanpos = pri_fixup_principle(pri, chanpos, ev->hold_ack.call);
   if (chanpos < 0) {
      /* Should never happen. */
      sig_pri_kill_call(pri, ev->hold_ack.call, PRI_CAUSE_NORMAL_TEMPORARY_FAILURE);
      return;
   }

   sig_pri_lock_private(pri->pvts[chanpos]);
   callid = func_pri_dchannel_chanpos_callid(pri, chanpos);

   sig_pri_handle_subcmds(pri, chanpos, ev->e, ev->hold_ack.subcmds, ev->hold_ack.call);
   sig_pri_moh_fsm_event(pri->pvts[chanpos]->owner, pri->pvts[chanpos],
      SIG_PRI_MOH_EVENT_HOLD_ACK);
   sig_pri_unlock_private(pri->pvts[chanpos]);
   sig_pri_span_devstate_changed(pri);

   if (callid) {
      ast_callid_unref(callid);
      ast_callid_threadassoc_remove();
   }
}
#endif   /* defined(HAVE_PRI_CALL_HOLD) */

#if defined(HAVE_PRI_CALL_HOLD)
/*!
 * \internal
 * \brief Handle the hold reject event from libpri.
 * \since 10.0
 *
 * \param pri PRI span control structure.
 * \param ev Hold reject event received.
 *
 * \note Assumes the pri->lock is already obtained.
 *
 * \return Nothing
 */
static void sig_pri_handle_hold_rej(struct sig_pri_span *pri, pri_event *ev)
{
   int chanpos;
   struct ast_callid *callid;

   chanpos = pri_find_principle(pri, ev->hold_rej.channel, ev->hold_rej.call);
   if (chanpos < 0) {
      ast_log(LOG_WARNING, "Span %d: Could not find principle for HOLD_REJECT\n",
         pri->span);
      sig_pri_kill_call(pri, ev->hold_rej.call, PRI_CAUSE_NORMAL_TEMPORARY_FAILURE);
      return;
   }
   chanpos = pri_fixup_principle(pri, chanpos, ev->hold_rej.call);
   if (chanpos < 0) {
      /* Should never happen. */
      sig_pri_kill_call(pri, ev->hold_rej.call, PRI_CAUSE_NORMAL_TEMPORARY_FAILURE);
      return;
   }

   ast_debug(1, "Span %d: HOLD_REJECT cause: %d(%s)\n", pri->span,
      ev->hold_rej.cause, pri_cause2str(ev->hold_rej.cause));

   sig_pri_lock_private(pri->pvts[chanpos]);
   callid = func_pri_dchannel_chanpos_callid(pri, chanpos);

   sig_pri_handle_subcmds(pri, chanpos, ev->e, ev->hold_rej.subcmds, ev->hold_rej.call);
   sig_pri_moh_fsm_event(pri->pvts[chanpos]->owner, pri->pvts[chanpos],
      SIG_PRI_MOH_EVENT_HOLD_REJ);
   sig_pri_unlock_private(pri->pvts[chanpos]);

   if (callid) {
      ast_callid_unref(callid);
      ast_callid_threadassoc_remove();
   }
}
#endif   /* defined(HAVE_PRI_CALL_HOLD) */

#if defined(HAVE_PRI_CALL_HOLD)
/*!
 * \internal
 * \brief Handle the retrieve event from libpri.
 * \since 1.8
 *
 * \param pri PRI span control structure.
 * \param ev Retrieve event received.
 *
 * \note Assumes the pri->lock is already obtained.
 *
 * \return Nothing
 */
static void sig_pri_handle_retrieve(struct sig_pri_span *pri, pri_event *ev)
{
   int chanpos;
   struct ast_callid *callid;

   if (!(ev->retrieve.channel & PRI_HELD_CALL)) {
      /* The call is not currently held. */
      pri_retrieve_rej(pri->pri, ev->retrieve.call,
         PRI_CAUSE_RESOURCE_UNAVAIL_UNSPECIFIED);
      return;
   }
   if (pri_find_principle_by_call(pri, ev->retrieve.call) < 0) {
      ast_log(LOG_WARNING, "Span %d: Received RETRIEVE for unknown call.\n", pri->span);
      pri_retrieve_rej(pri->pri, ev->retrieve.call,
         PRI_CAUSE_RESOURCE_UNAVAIL_UNSPECIFIED);
      return;
   }
   if (PRI_CHANNEL(ev->retrieve.channel) == 0xFF) {
      chanpos = pri_find_empty_chan(pri, 1);
   } else {
      chanpos = pri_find_principle(pri,
         ev->retrieve.channel & ~PRI_HELD_CALL, ev->retrieve.call);
      if (ev->retrieve.flexible
         && (chanpos < 0 || !sig_pri_is_chan_available(pri->pvts[chanpos]))) {
         /*
          * Channel selection is flexible and the requested channel
          * is bad or not available.  Pick another channel.
          */
         chanpos = pri_find_empty_chan(pri, 1);
      }
   }
   if (chanpos < 0) {
      pri_retrieve_rej(pri->pri, ev->retrieve.call,
         ev->retrieve.flexible ? PRI_CAUSE_NORMAL_CIRCUIT_CONGESTION
         : PRI_CAUSE_REQUESTED_CHAN_UNAVAIL);
      return;
   }
   chanpos = pri_fixup_principle(pri, chanpos, ev->retrieve.call);
   if (chanpos < 0) {
      /* Channel is already in use. */
      pri_retrieve_rej(pri->pri, ev->retrieve.call,
         PRI_CAUSE_REQUESTED_CHAN_UNAVAIL);
      return;
   }
   sig_pri_lock_private(pri->pvts[chanpos]);
   callid = func_pri_dchannel_chanpos_callid(pri, chanpos);
   sig_pri_handle_subcmds(pri, chanpos, ev->e, ev->retrieve.subcmds, ev->retrieve.call);
   sig_pri_lock_owner(pri, chanpos);
   pri_queue_control(pri, chanpos, AST_CONTROL_UNHOLD);
   if (pri->pvts[chanpos]->owner) {
      sig_pri_ami_hold_event(pri->pvts[chanpos]->owner, 0);
      ast_channel_unlock(pri->pvts[chanpos]->owner);
   }
   pri_retrieve_ack(pri->pri, ev->retrieve.call,
      PVT_TO_CHANNEL(pri->pvts[chanpos]));
   sig_pri_moh_fsm_event(pri->pvts[chanpos]->owner, pri->pvts[chanpos],
      SIG_PRI_MOH_EVENT_REMOTE_RETRIEVE_ACK);
   sig_pri_unlock_private(pri->pvts[chanpos]);
   sig_pri_span_devstate_changed(pri);

   if (callid) {
      ast_callid_unref(callid);
      ast_callid_threadassoc_remove();
   }
}
#endif   /* defined(HAVE_PRI_CALL_HOLD) */

#if defined(HAVE_PRI_CALL_HOLD)
/*!
 * \internal
 * \brief Handle the retrieve acknowledge event from libpri.
 * \since 10.0
 *
 * \param pri PRI span control structure.
 * \param ev Retrieve acknowledge event received.
 *
 * \note Assumes the pri->lock is already obtained.
 *
 * \return Nothing
 */
static void sig_pri_handle_retrieve_ack(struct sig_pri_span *pri, pri_event *ev)
{
   int chanpos;
   struct ast_callid *callid;

   chanpos = pri_find_fixup_principle(pri, ev->retrieve_ack.channel,
      ev->retrieve_ack.call);
   if (chanpos < 0) {
      return;
   }

   sig_pri_lock_private(pri->pvts[chanpos]);
   callid = func_pri_dchannel_chanpos_callid(pri, chanpos);

   sig_pri_handle_subcmds(pri, chanpos, ev->e, ev->retrieve_ack.subcmds,
      ev->retrieve_ack.call);
   sig_pri_moh_fsm_event(pri->pvts[chanpos]->owner, pri->pvts[chanpos],
      SIG_PRI_MOH_EVENT_RETRIEVE_ACK);
   sig_pri_unlock_private(pri->pvts[chanpos]);
   sig_pri_span_devstate_changed(pri);

   if (callid) {
      ast_callid_unref(callid);
      ast_callid_threadassoc_remove();
   }
}
#endif   /* defined(HAVE_PRI_CALL_HOLD) */

#if defined(HAVE_PRI_CALL_HOLD)
/*!
 * \internal
 * \brief Handle the retrieve reject event from libpri.
 * \since 10.0
 *
 * \param pri PRI span control structure.
 * \param ev Retrieve reject event received.
 *
 * \note Assumes the pri->lock is already obtained.
 *
 * \return Nothing
 */
static void sig_pri_handle_retrieve_rej(struct sig_pri_span *pri, pri_event *ev)
{
   int chanpos;
   struct ast_callid *callid;

   chanpos = pri_find_principle(pri, ev->retrieve_rej.channel, ev->retrieve_rej.call);
   if (chanpos < 0) {
      ast_log(LOG_WARNING, "Span %d: Could not find principle for RETRIEVE_REJECT\n",
         pri->span);
      sig_pri_kill_call(pri, ev->retrieve_rej.call, PRI_CAUSE_NORMAL_TEMPORARY_FAILURE);
      return;
   }
   chanpos = pri_fixup_principle(pri, chanpos, ev->retrieve_rej.call);
   if (chanpos < 0) {
      /* Should never happen. */
      sig_pri_kill_call(pri, ev->retrieve_rej.call, PRI_CAUSE_NORMAL_TEMPORARY_FAILURE);
      return;
   }

   ast_debug(1, "Span %d: RETRIEVE_REJECT cause: %d(%s)\n", pri->span,
      ev->retrieve_rej.cause, pri_cause2str(ev->retrieve_rej.cause));

   sig_pri_lock_private(pri->pvts[chanpos]);
   callid = func_pri_dchannel_chanpos_callid(pri, chanpos);

   sig_pri_handle_subcmds(pri, chanpos, ev->e, ev->retrieve_rej.subcmds,
      ev->retrieve_rej.call);
   sig_pri_moh_fsm_event(pri->pvts[chanpos]->owner, pri->pvts[chanpos],
      SIG_PRI_MOH_EVENT_RETRIEVE_REJ);
   sig_pri_unlock_private(pri->pvts[chanpos]);

   if (callid) {
      ast_callid_unref(callid);
      ast_callid_threadassoc_remove();
   }
}
#endif   /* defined(HAVE_PRI_CALL_HOLD) */

static void *pri_dchannel(void *vpri)
{
   struct sig_pri_span *pri = vpri;
   pri_event *e;
   struct pollfd fds[SIG_PRI_NUM_DCHANS];
   int res;
   int x;
   int law;
   struct ast_channel *c;
   struct timeval tv, lowest, *next;
   int doidling=0;
   char *cc;
   time_t t;
   int i, which=-1;
   int numdchans;
   pthread_t threadid;
   char ani2str[6];
   char plancallingnum[AST_MAX_EXTENSION];
   char plancallingani[AST_MAX_EXTENSION];
   char calledtonstr[10];
   struct timeval lastidle = { 0, 0 };
   pthread_t p;
   struct ast_channel *idle;
   char idlen[80];
   int nextidle = -1;
   int haveidles;
   int activeidles;
   unsigned int len;

   gettimeofday(&lastidle, NULL);
   pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, NULL);

   if (!ast_strlen_zero(pri->idledial) && !ast_strlen_zero(pri->idleext)) {
      /* Need to do idle dialing, check to be sure though */
      cc = strchr(pri->idleext, '@');
      if (cc) {
         *cc = '\0';
         cc++;
         ast_copy_string(pri->idlecontext, cc, sizeof(pri->idlecontext));
#if 0
         /* Extensions may not be loaded yet */
         if (!ast_exists_extension(NULL, pri->idlecontext, pri->idleext, 1, NULL))
            ast_log(LOG_WARNING, "Extension '%s @ %s' does not exist\n", pri->idleext, pri->idlecontext);
         else
#endif
            doidling = 1;
      } else
         ast_log(LOG_WARNING, "Idle dial string '%s' lacks '@context'\n", pri->idleext);
   }
   for (;;) {
      struct ast_callid *callid = NULL;

      for (i = 0; i < SIG_PRI_NUM_DCHANS; i++) {
         if (!pri->dchans[i])
            break;
         fds[i].fd = pri->fds[i];
         fds[i].events = POLLIN | POLLPRI;
         fds[i].revents = 0;
      }
      numdchans = i;
      time(&t);
      ast_mutex_lock(&pri->lock);
      if (pri->switchtype != PRI_SWITCH_GR303_TMC && (pri->sig != SIG_BRI_PTMP) && (pri->resetinterval > 0)) {
         if (pri->resetting && pri_is_up(pri)) {
            if (pri->resetpos < 0) {
               pri_check_restart(pri);
               if (pri->resetting) {
                  sig_pri_span_devstate_changed(pri);
               }
            }
         } else {
            if (!pri->resetting  && (t - pri->lastreset) >= pri->resetinterval) {
               pri->resetting = 1;
               pri->resetpos = -1;
            }
         }
      }
      /* Look for any idle channels if appropriate */
      if (doidling && pri_is_up(pri)) {
         nextidle = -1;
         haveidles = 0;
         activeidles = 0;
         for (x = pri->numchans; x >= 0; x--) {
            if (pri->pvts[x] && !pri->pvts[x]->no_b_channel) {
               if (sig_pri_is_chan_available(pri->pvts[x])) {
                  if (haveidles < pri->minunused) {
                     haveidles++;
                  } else {
                     nextidle = x;
                     break;
                  }
               } else if (pri->pvts[x]->owner && pri->pvts[x]->isidlecall) {
                  activeidles++;
               }
            }
         }
         if (nextidle > -1) {
            if (ast_tvdiff_ms(ast_tvnow(), lastidle) > 1000) {
               /* Don't create a new idle call more than once per second */
               snprintf(idlen, sizeof(idlen), "%d/%s", pri->pvts[nextidle]->channel, pri->idledial);
               pri->pvts[nextidle]->allocated = 1;
               /*
                * Release the PRI lock while we create the channel so other
                * threads can send D channel messages.
                */
               ast_mutex_unlock(&pri->lock);
               /*
                * We already have the B channel reserved for this call.  We
                * just need to make sure that sig_pri_hangup() has completed
                * cleaning up before continuing.
                */
               sig_pri_lock_private(pri->pvts[nextidle]);
               sig_pri_unlock_private(pri->pvts[nextidle]);
               idle = sig_pri_request(pri->pvts[nextidle], AST_FORMAT_ULAW, NULL, 0);
               ast_mutex_lock(&pri->lock);
               if (idle) {
                  pri->pvts[nextidle]->isidlecall = 1;
                  if (ast_pthread_create_background(&p, NULL, do_idle_thread, pri->pvts[nextidle])) {
                     ast_log(LOG_WARNING, "Unable to start new thread for idle channel '%s'\n", ast_channel_name(idle));
                     ast_mutex_unlock(&pri->lock);
                     ast_hangup(idle);
                     ast_mutex_lock(&pri->lock);
                  }
               } else {
                  pri->pvts[nextidle]->allocated = 0;
                  ast_log(LOG_WARNING, "Unable to request channel 'DAHDI/%s' for idle call\n", idlen);
               }
               gettimeofday(&lastidle, NULL);
            }
         } else if ((haveidles < pri->minunused) &&
            (activeidles > pri->minidle)) {
            /* Mark something for hangup if there is something
               that can be hungup */
            for (x = pri->numchans; x >= 0; x--) {
               /* find a candidate channel */
               if (pri->pvts[x] && pri->pvts[x]->owner && pri->pvts[x]->isidlecall) {
                  ast_channel_softhangup_internal_flag_add(pri->pvts[x]->owner, AST_SOFTHANGUP_DEV);
                  haveidles++;
                  /* Stop if we have enough idle channels or
                    can't spare any more active idle ones */
                  if ((haveidles >= pri->minunused) ||
                     (activeidles <= pri->minidle))
                     break;
               }
            }
         }
      }
      /* Start with reasonable max */
      if (doidling || pri->resetting) {
         /*
          * Make sure we stop at least once per second if we're
          * monitoring idle channels
          */
         lowest = ast_tv(1, 0);
      } else {
         /* Don't poll for more than 60 seconds */
         lowest = ast_tv(60, 0);
      }
      for (i = 0; i < SIG_PRI_NUM_DCHANS; i++) {
         if (!pri->dchans[i]) {
            /* We scanned all D channels on this span. */
            break;
         }
         next = pri_schedule_next(pri->dchans[i]);
         if (next) {
            /* We need relative time here */
            tv = ast_tvsub(*next, ast_tvnow());
            if (tv.tv_sec < 0) {
               /*
                * A timer has already expired.
                * By definition zero time is the lowest so we can quit early.
                */
               lowest = ast_tv(0, 0);
               break;
            }
            if (ast_tvcmp(tv, lowest) < 0) {
               lowest = tv;
            }
         }
      }
      ast_mutex_unlock(&pri->lock);

      pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, NULL);
      pthread_testcancel();
      e = NULL;
      res = poll(fds, numdchans, lowest.tv_sec * 1000 + lowest.tv_usec / 1000);
      pthread_testcancel();
      pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, NULL);

      ast_mutex_lock(&pri->lock);
      if (!res) {
         for (which = 0; which < SIG_PRI_NUM_DCHANS; which++) {
            if (!pri->dchans[which])
               break;
            /* Just a timeout, run the scheduler */
            e = pri_schedule_run(pri->dchans[which]);
            if (e)
               break;
         }
      } else if (res > -1) {
         for (which = 0; which < SIG_PRI_NUM_DCHANS; which++) {
            if (!pri->dchans[which])
               break;
            if (fds[which].revents & POLLPRI) {
               sig_pri_handle_dchan_exception(pri, which);
            } else if (fds[which].revents & POLLIN) {
               e = pri_check_event(pri->dchans[which]);
            }
            if (e)
               break;
         }
      } else if (errno != EINTR)
         ast_log(LOG_WARNING, "pri_event returned error %d (%s)\n", errno, strerror(errno));

      if (e) {
         int chanpos = -1;
         char cause_str[35];

         if (pri->debug) {
            ast_verbose("Span %d: Processing event %s(%d)\n",
               pri->span, pri_event2str(e->e), e->e);
         }

         if (e->e != PRI_EVENT_DCHAN_DOWN) {
            if (!(pri->dchanavail[which] & DCHAN_UP)) {
               ast_verb(2, "%s D-Channel on span %d up\n", pri_order(which), pri->span);
            }
            pri->dchanavail[which] |= DCHAN_UP;
         } else {
            if (pri->dchanavail[which] & DCHAN_UP) {
               ast_verb(2, "%s D-Channel on span %d down\n", pri_order(which), pri->span);
            }
            pri->dchanavail[which] &= ~DCHAN_UP;
         }

         if ((e->e != PRI_EVENT_DCHAN_UP) && (e->e != PRI_EVENT_DCHAN_DOWN) && (pri->pri != pri->dchans[which]))
            /* Must be an NFAS group that has the secondary dchan active */
            pri->pri = pri->dchans[which];

         switch (e->e) {
         case PRI_EVENT_DCHAN_UP:
            pri->no_d_channels = 0;
            if (!pri->pri) {
               pri_find_dchan(pri);
            }

            /* Note presense of D-channel */
            time(&pri->lastreset);

            /* Restart in 5 seconds */
            if (pri->resetinterval > -1) {
               pri->lastreset -= pri->resetinterval;
               pri->lastreset += 5;
            }
            /* Take the channels from inalarm condition */
            pri->resetting = 0;
            for (i = 0; i < pri->numchans; i++) {
               if (pri->pvts[i]) {
                  sig_pri_set_alarm(pri->pvts[i], 0);
               }
            }
            sig_pri_span_devstate_changed(pri);
            break;
         case PRI_EVENT_DCHAN_DOWN:
            pri_find_dchan(pri);
            if (!pri_is_up(pri)) {
               if (pri->sig == SIG_BRI_PTMP) {
                  /*
                   * For PTMP connections with non-persistent layer 2 we want to
                   * *not* declare inalarm unless there actually is an alarm.
                   */
                  break;
               }
               /* Hangup active channels and put them in alarm mode */
               pri->resetting = 0;
               for (i = 0; i < pri->numchans; i++) {
                  struct sig_pri_chan *p = pri->pvts[i];

                  if (p) {
                     if (pri_get_timer(p->pri->pri, PRI_TIMER_T309) < 0) {
                        /* T309 is not enabled : destroy calls when alarm occurs */
                        if (p->call) {
                           pri_destroycall(p->pri->pri, p->call);
                           p->call = NULL;
                        }
                        if (p->owner)
                           ast_channel_softhangup_internal_flag_add(p->owner, AST_SOFTHANGUP_DEV);
                     }
                     sig_pri_set_alarm(p, 1);
                  }
               }
               sig_pri_span_devstate_changed(pri);
            }
            break;
         case PRI_EVENT_RESTART:
            if (e->restart.channel > -1 && PRI_CHANNEL(e->restart.channel) != 0xFF) {
               chanpos = pri_find_principle(pri, e->restart.channel, NULL);
               if (chanpos < 0)
                  ast_log(LOG_WARNING,
                     "Span %d: Restart requested on odd/unavailable channel number %d/%d\n",
                     pri->span, PRI_SPAN(e->restart.channel),
                     PRI_CHANNEL(e->restart.channel));
               else {
                  int skipit = 0;
#if defined(HAVE_PRI_SERVICE_MESSAGES)
                  unsigned why;

                  why = pri->pvts[chanpos]->service_status;
                  if (why) {
                     ast_log(LOG_NOTICE,
                        "Span %d: Channel %d/%d out-of-service (reason: %s), ignoring RESTART\n",
                        pri->span, PRI_SPAN(e->restart.channel),
                        PRI_CHANNEL(e->restart.channel),
                        (why & SRVST_FAREND) ? (why & SRVST_NEAREND) ? "both ends" : "far end" : "near end");
                     skipit = 1;
                  }
#endif   /* defined(HAVE_PRI_SERVICE_MESSAGES) */
                  sig_pri_lock_private(pri->pvts[chanpos]);
                  if (!skipit) {
                     ast_verb(3, "Span %d: Channel %d/%d restarted\n", pri->span,
                        PRI_SPAN(e->restart.channel),
                        PRI_CHANNEL(e->restart.channel));
                     if (pri->pvts[chanpos]->call) {
                        pri_destroycall(pri->pri, pri->pvts[chanpos]->call);
                        pri->pvts[chanpos]->call = NULL;
                     }
                  }
                  /* Force soft hangup if appropriate */
                  if (pri->pvts[chanpos]->owner)
                     ast_channel_softhangup_internal_flag_add(pri->pvts[chanpos]->owner, AST_SOFTHANGUP_DEV);
                  sig_pri_unlock_private(pri->pvts[chanpos]);
               }
            } else {
               ast_verb(3, "Restart requested on entire span %d\n", pri->span);
               for (x = 0; x < pri->numchans; x++)
                  if (pri->pvts[x]) {
                     sig_pri_lock_private(pri->pvts[x]);
                     if (pri->pvts[x]->call) {
                        pri_destroycall(pri->pri, pri->pvts[x]->call);
                        pri->pvts[x]->call = NULL;
                     }
                     if (pri->pvts[x]->owner)
                        ast_channel_softhangup_internal_flag_add(pri->pvts[x]->owner, AST_SOFTHANGUP_DEV);
                     sig_pri_unlock_private(pri->pvts[x]);
                  }
            }
            sig_pri_span_devstate_changed(pri);
            break;
         case PRI_EVENT_KEYPAD_DIGIT:
            if (sig_pri_is_cis_call(e->digit.channel)) {
               sig_pri_handle_cis_subcmds(pri, e->e, e->digit.subcmds,
                  e->digit.call);
               break;
            }
            chanpos = pri_find_principle_by_call(pri, e->digit.call);
            if (chanpos < 0) {
               ast_log(LOG_WARNING,
                  "Span %d: Received keypad digits for unknown call.\n", pri->span);
               break;
            }
            sig_pri_lock_private(pri->pvts[chanpos]);

            callid = func_pri_dchannel_chanpos_callid(pri, chanpos);

            sig_pri_handle_subcmds(pri, chanpos, e->e, e->digit.subcmds,
               e->digit.call);
            /* queue DTMF frame if the PBX for this call was already started (we're forwarding KEYPAD_DIGITs further on */
            if ((pri->overlapdial & DAHDI_OVERLAPDIAL_INCOMING)
               && pri->pvts[chanpos]->owner) {
               /* how to do that */
               int digitlen = strlen(e->digit.digits);
               int i;

               for (i = 0; i < digitlen; i++) {
                  struct ast_frame f = { AST_FRAME_DTMF, .subclass.integer = e->digit.digits[i], };

                  pri_queue_frame(pri, chanpos, &f);
               }
            }
            sig_pri_unlock_private(pri->pvts[chanpos]);
            break;

         case PRI_EVENT_INFO_RECEIVED:
            if (sig_pri_is_cis_call(e->ring.channel)) {
               sig_pri_handle_cis_subcmds(pri, e->e, e->ring.subcmds,
                  e->ring.call);
               break;
            }
            chanpos = pri_find_principle_by_call(pri, e->ring.call);
            if (chanpos < 0) {
               ast_log(LOG_WARNING,
                  "Span %d: Received INFORMATION for unknown call.\n", pri->span);
               break;
            }
            sig_pri_lock_private(pri->pvts[chanpos]);

            callid = func_pri_dchannel_chanpos_callid(pri, chanpos);

            sig_pri_handle_subcmds(pri, chanpos, e->e, e->ring.subcmds, e->ring.call);
            /* queue DTMF frame if the PBX for this call was already started (we're forwarding INFORMATION further on */
            if ((pri->overlapdial & DAHDI_OVERLAPDIAL_INCOMING)
               && pri->pvts[chanpos]->owner) {
               /* how to do that */
               int digitlen = strlen(e->ring.callednum);
               int i;

               for (i = 0; i < digitlen; i++) {
                  struct ast_frame f = { AST_FRAME_DTMF, .subclass.integer = e->ring.callednum[i], };

                  pri_queue_frame(pri, chanpos, &f);
               }
            }
            sig_pri_unlock_private(pri->pvts[chanpos]);
            break;
#if defined(HAVE_PRI_SERVICE_MESSAGES)
         case PRI_EVENT_SERVICE:
            chanpos = pri_find_principle(pri, e->service.channel, NULL);
            if (chanpos < 0) {
               ast_log(LOG_WARNING, "Received service change status %d on unconfigured channel %d/%d span %d\n",
                  e->service_ack.changestatus, PRI_SPAN(e->service_ack.channel), PRI_CHANNEL(e->service_ack.channel), pri->span);
            } else {
               char db_chan_name[20];
               char db_answer[5];
               int ch;
               unsigned *why;

               ch = pri->pvts[chanpos]->channel;
               snprintf(db_chan_name, sizeof(db_chan_name), "%s/%d:%d", dahdi_db, pri->span, ch);
               why = &pri->pvts[chanpos]->service_status;
               switch (e->service.changestatus) {
               case 0: /* in-service */
                  /* Far end wants to be in service now. */
                  ast_db_del(db_chan_name, SRVST_DBKEY);
                  *why &= ~SRVST_FAREND;
                  if (*why) {
                     snprintf(db_answer, sizeof(db_answer), "%s:%u",
                        SRVST_TYPE_OOS, *why);
                     ast_db_put(db_chan_name, SRVST_DBKEY, db_answer);
                  } else {
                     sig_pri_span_devstate_changed(pri);
                  }
                  break;
               case 2: /* out-of-service */
                  /* Far end wants to be out-of-service now. */
                  ast_db_del(db_chan_name, SRVST_DBKEY);
                  *why |= SRVST_FAREND;
                  snprintf(db_answer, sizeof(db_answer), "%s:%u", SRVST_TYPE_OOS,
                     *why);
                  ast_db_put(db_chan_name, SRVST_DBKEY, db_answer);
                  sig_pri_span_devstate_changed(pri);
                  break;
               default:
                  ast_log(LOG_ERROR, "Huh?  changestatus is: %d\n", e->service.changestatus);
                  break;
               }
               ast_log(LOG_NOTICE, "Channel %d/%d span %d (logical: %d) received a change of service message, status '%d'\n",
                  PRI_SPAN(e->service.channel), PRI_CHANNEL(e->service.channel), pri->span, ch, e->service.changestatus);
            }
            break;
         case PRI_EVENT_SERVICE_ACK:
            chanpos = pri_find_principle(pri, e->service_ack.channel, NULL);
            if (chanpos < 0) {
               ast_log(LOG_WARNING, "Received service acknowledge change status '%d' on unconfigured channel %d/%d span %d\n",
                  e->service_ack.changestatus, PRI_SPAN(e->service_ack.channel), PRI_CHANNEL(e->service_ack.channel), pri->span);
            } else {
               ast_debug(2, "Channel %d/%d span %d received a change os service acknowledgement message, status '%d'\n",
                  PRI_SPAN(e->service_ack.channel), PRI_CHANNEL(e->service_ack.channel), pri->span, e->service_ack.changestatus);
            }
            break;
#endif   /* defined(HAVE_PRI_SERVICE_MESSAGES) */
         case PRI_EVENT_RING:
            if (!ast_strlen_zero(pri->msn_list)
               && !sig_pri_msn_match(pri->msn_list, e->ring.callednum)) {
               /* The call is not for us so ignore it. */
               ast_verb(3,
                  "Ignoring call to '%s' on span %d.  Its not in the MSN list: %s\n",
                  e->ring.callednum, pri->span, pri->msn_list);
               pri_destroycall(pri->pri, e->ring.call);
               break;
            }
            if (sig_pri_is_cis_call(e->ring.channel)) {
               sig_pri_handle_cis_subcmds(pri, e->e, e->ring.subcmds,
                  e->ring.call);
               break;
            }
            chanpos = pri_find_principle_by_call(pri, e->ring.call);
            if (-1 < chanpos) {
               /* Libpri has already filtered out duplicate SETUPs. */
               ast_log(LOG_WARNING,
                  "Span %d: Got SETUP with duplicate call ptr (%p).  Dropping call.\n",
                  pri->span, e->ring.call);
               pri_hangup(pri->pri, e->ring.call, PRI_CAUSE_NORMAL_TEMPORARY_FAILURE);
               break;
            }
            if (e->ring.channel == -1 || PRI_CHANNEL(e->ring.channel) == 0xFF) {
               /* Any channel requested. */
               chanpos = pri_find_empty_chan(pri, 1);
               if (-1 < chanpos) {
                  callid = func_pri_dchannel_new_callid();
               }
            } else if (PRI_CHANNEL(e->ring.channel) == 0x00) {
               /* No channel specified. */
#if defined(HAVE_PRI_CALL_WAITING)
               if (!pri->allow_call_waiting_calls)
#endif   /* defined(HAVE_PRI_CALL_WAITING) */
               {
                  /* We will not accept incoming call waiting calls. */
                  pri_hangup(pri->pri, e->ring.call, PRI_CAUSE_NORMAL_CIRCUIT_CONGESTION);
                  break;
               }
#if defined(HAVE_PRI_CALL_WAITING)
               chanpos = pri_find_empty_nobch(pri);
               if (chanpos < 0) {
                  /* We could not find/create a call interface. */
                  pri_hangup(pri->pri, e->ring.call, PRI_CAUSE_NORMAL_CIRCUIT_CONGESTION);
                  break;
               }

               callid = func_pri_dchannel_new_callid();

               /* Setup the call interface to use. */
               sig_pri_init_config(pri->pvts[chanpos], pri);
#endif   /* defined(HAVE_PRI_CALL_WAITING) */
            } else {
               /* A channel is specified. */
               callid = func_pri_dchannel_new_callid();
               chanpos = pri_find_principle(pri, e->ring.channel, e->ring.call);
               if (chanpos < 0) {
                  ast_log(LOG_WARNING,
                     "Span %d: SETUP on unconfigured channel %d/%d\n",
                     pri->span, PRI_SPAN(e->ring.channel),
                     PRI_CHANNEL(e->ring.channel));
               } else {
                  switch (pri->pvts[chanpos]->resetting) {
                  case SIG_PRI_RESET_IDLE:
                     break;
                  case SIG_PRI_RESET_ACTIVE:
                     /*
                      * The peer may have lost the expected ack or not received the
                      * RESTART yet.
                      */
                     pri->pvts[chanpos]->resetting = SIG_PRI_RESET_NO_ACK;
                     break;
                  case SIG_PRI_RESET_NO_ACK:
                     /* The peer likely is not going to ack the RESTART. */
                     ast_debug(1,
                        "Span %d: Second SETUP while waiting for RESTART ACKNOWLEDGE on channel %d/%d\n",
                        pri->span, PRI_SPAN(e->ring.channel),
                        PRI_CHANNEL(e->ring.channel));

                     /* Assume we got the ack. */
                     pri->pvts[chanpos]->resetting = SIG_PRI_RESET_IDLE;
                     if (pri->resetting) {
                        /* Go on to the next idle channel to RESTART. */
                        pri_check_restart(pri);
                     }
                     break;
                  }
                  if (!sig_pri_is_chan_available(pri->pvts[chanpos])) {
                     /* This is where we handle initial glare */
                     ast_debug(1,
                        "Span %d: SETUP requested unavailable channel %d/%d.  Attempting to renegotiate.\n",
                        pri->span, PRI_SPAN(e->ring.channel),
                        PRI_CHANNEL(e->ring.channel));
                     chanpos = -1;
                  }
               }
#if defined(ALWAYS_PICK_CHANNEL)
               if (e->ring.flexible) {
                  chanpos = -1;
               }
#endif   /* defined(ALWAYS_PICK_CHANNEL) */
               if (chanpos < 0 && e->ring.flexible) {
                  /* We can try to pick another channel. */
                  chanpos = pri_find_empty_chan(pri, 1);
               }
            }
            if (chanpos < 0) {
               if (e->ring.flexible) {
                  pri_hangup(pri->pri, e->ring.call, PRI_CAUSE_NORMAL_CIRCUIT_CONGESTION);
               } else {
                  pri_hangup(pri->pri, e->ring.call, PRI_CAUSE_REQUESTED_CHAN_UNAVAIL);
               }
               break;
            }

            sig_pri_lock_private(pri->pvts[chanpos]);

            /* Mark channel as in use so noone else will steal it. */
            pri->pvts[chanpos]->call = e->ring.call;

            /* Use plancallingnum as a scratch buffer since it is initialized next. */
            apply_plan_to_existing_number(plancallingnum, sizeof(plancallingnum), pri,
               e->ring.redirectingnum, e->ring.callingplanrdnis);
            sig_pri_set_rdnis(pri->pvts[chanpos], plancallingnum);

            /* Setup caller-id info */
            apply_plan_to_existing_number(plancallingnum, sizeof(plancallingnum), pri,
               e->ring.callingnum, e->ring.callingplan);
            pri->pvts[chanpos]->cid_ani2 = 0;
            if (pri->pvts[chanpos]->use_callerid) {
               ast_shrink_phone_number(plancallingnum);
               ast_copy_string(pri->pvts[chanpos]->cid_num, plancallingnum, sizeof(pri->pvts[chanpos]->cid_num));
#ifdef PRI_ANI
               apply_plan_to_existing_number(plancallingani, sizeof(plancallingani),
                  pri, e->ring.callingani, e->ring.callingplanani);
               ast_shrink_phone_number(plancallingani);
               ast_copy_string(pri->pvts[chanpos]->cid_ani, plancallingani,
                  sizeof(pri->pvts[chanpos]->cid_ani));
#endif
               pri->pvts[chanpos]->cid_subaddr[0] = '\0';
#if defined(HAVE_PRI_SUBADDR)
               if (e->ring.calling.subaddress.valid) {
                  struct ast_party_subaddress calling_subaddress;

                  ast_party_subaddress_init(&calling_subaddress);
                  sig_pri_set_subaddress(&calling_subaddress,
                     &e->ring.calling.subaddress);
                  if (calling_subaddress.str) {
                     ast_copy_string(pri->pvts[chanpos]->cid_subaddr,
                        calling_subaddress.str,
                        sizeof(pri->pvts[chanpos]->cid_subaddr));
                  }
                  ast_party_subaddress_free(&calling_subaddress);
               }
#endif /* defined(HAVE_PRI_SUBADDR) */
               ast_copy_string(pri->pvts[chanpos]->cid_name, e->ring.callingname, sizeof(pri->pvts[chanpos]->cid_name));
               pri->pvts[chanpos]->cid_ton = e->ring.callingplan; /* this is the callingplan (TON/NPI), e->ring.callingplan>>4 would be the TON */
               pri->pvts[chanpos]->callingpres = e->ring.callingpres;
               if (e->ring.ani2 >= 0) {
                  pri->pvts[chanpos]->cid_ani2 = e->ring.ani2;
               }
            } else {
               pri->pvts[chanpos]->cid_num[0] = '\0';
               pri->pvts[chanpos]->cid_subaddr[0] = '\0';
               pri->pvts[chanpos]->cid_ani[0] = '\0';
               pri->pvts[chanpos]->cid_name[0] = '\0';
               pri->pvts[chanpos]->cid_ton = 0;
               pri->pvts[chanpos]->callingpres = 0;
            }

            /* Setup the user tag for party id's from this device for this call. */
            if (pri->append_msn_to_user_tag) {
               snprintf(pri->pvts[chanpos]->user_tag,
                  sizeof(pri->pvts[chanpos]->user_tag), "%s_%s",
                  pri->initial_user_tag,
                  pri->nodetype == PRI_NETWORK
                     ? plancallingnum : e->ring.callednum);
            } else {
               ast_copy_string(pri->pvts[chanpos]->user_tag,
                  pri->initial_user_tag, sizeof(pri->pvts[chanpos]->user_tag));
            }

            sig_pri_set_caller_id(pri->pvts[chanpos]);

            /* Set DNID on all incoming calls -- even immediate */
            sig_pri_set_dnid(pri->pvts[chanpos], e->ring.callednum);

            /* If immediate=yes go to s|1 */
            if (pri->pvts[chanpos]->immediate) {
               ast_verb(3, "Going to extension s|1 because of immediate=yes\n");
               pri->pvts[chanpos]->exten[0] = 's';
               pri->pvts[chanpos]->exten[1] = '\0';
            }
            /* Get called number */
            else if (!ast_strlen_zero(e->ring.callednum)) {
               ast_copy_string(pri->pvts[chanpos]->exten, e->ring.callednum, sizeof(pri->pvts[chanpos]->exten));
            } else if (pri->overlapdial)
               pri->pvts[chanpos]->exten[0] = '\0';
            else {
               /* Some PRI circuits are set up to send _no_ digits.  Handle them as 's'. */
               pri->pvts[chanpos]->exten[0] = 's';
               pri->pvts[chanpos]->exten[1] = '\0';
            }
            /* No number yet, but received "sending complete"? */
            if (e->ring.complete && (ast_strlen_zero(e->ring.callednum))) {
               ast_verb(3, "Going to extension s|1 because of Complete received\n");
               pri->pvts[chanpos]->exten[0] = 's';
               pri->pvts[chanpos]->exten[1] = '\0';
            }

            /* Make sure extension exists (or in overlap dial mode, can exist) */
            if (((pri->overlapdial & DAHDI_OVERLAPDIAL_INCOMING) && ast_canmatch_extension(NULL, pri->pvts[chanpos]->context, pri->pvts[chanpos]->exten, 1, pri->pvts[chanpos]->cid_num)) ||
               ast_exists_extension(NULL, pri->pvts[chanpos]->context, pri->pvts[chanpos]->exten, 1, pri->pvts[chanpos]->cid_num)) {
               /* Select audio companding mode. */
               switch (e->ring.layer1) {
               case PRI_LAYER_1_ALAW:
                  law = SIG_PRI_ALAW;
                  break;
               case PRI_LAYER_1_ULAW:
                  law = SIG_PRI_ULAW;
                  break;
               default:
                  /* This is a data call to us. */
                  law = SIG_PRI_DEFLAW;
                  break;
               }

               if (e->ring.complete || !(pri->overlapdial & DAHDI_OVERLAPDIAL_INCOMING)) {
                  /* Just announce proceeding */
                  pri->pvts[chanpos]->call_level = SIG_PRI_CALL_LEVEL_PROCEEDING;
                  pri_proceeding(pri->pri, e->ring.call, PVT_TO_CHANNEL(pri->pvts[chanpos]), 0);
               } else if (pri->switchtype == PRI_SWITCH_GR303_TMC) {
                  pri->pvts[chanpos]->call_level = SIG_PRI_CALL_LEVEL_CONNECT;
                  pri_answer(pri->pri, e->ring.call, PVT_TO_CHANNEL(pri->pvts[chanpos]), 1);
               } else {
                  pri->pvts[chanpos]->call_level = SIG_PRI_CALL_LEVEL_OVERLAP;
                  pri_need_more_info(pri->pri, e->ring.call, PVT_TO_CHANNEL(pri->pvts[chanpos]), 1);
               }

               /* Start PBX */
               if (!e->ring.complete
                  && (pri->overlapdial & DAHDI_OVERLAPDIAL_INCOMING)
                  && ast_matchmore_extension(NULL, pri->pvts[chanpos]->context, pri->pvts[chanpos]->exten, 1, pri->pvts[chanpos]->cid_num)) {
                  /*
                   * Release the PRI lock while we create the channel so other
                   * threads can send D channel messages.  We must also release
                   * the private lock to prevent deadlock while creating the
                   * channel.
                   */
                  sig_pri_unlock_private(pri->pvts[chanpos]);
                  ast_mutex_unlock(&pri->lock);
                  c = sig_pri_new_ast_channel(pri->pvts[chanpos],
                     AST_STATE_RESERVED, law, e->ring.ctype,
                     pri->pvts[chanpos]->exten, NULL);
                  ast_mutex_lock(&pri->lock);
                  sig_pri_lock_private(pri->pvts[chanpos]);
                  if (c) {
#if defined(HAVE_PRI_SUBADDR)
                     if (e->ring.calling.subaddress.valid) {
                        /* Set Calling Subaddress */
                        sig_pri_lock_owner(pri, chanpos);
                        sig_pri_set_subaddress(
                           &ast_channel_caller(pri->pvts[chanpos]->owner)->id.subaddress,
                           &e->ring.calling.subaddress);
                        if (!e->ring.calling.subaddress.type
                           && !ast_strlen_zero(
                              (char *) e->ring.calling.subaddress.data)) {
                           /* NSAP */
                           pbx_builtin_setvar_helper(c, "CALLINGSUBADDR",
                              (char *) e->ring.calling.subaddress.data);
                        }
                        ast_channel_unlock(c);
                     }
                     if (e->ring.called_subaddress.valid) {
                        /* Set Called Subaddress */
                        sig_pri_lock_owner(pri, chanpos);
                        sig_pri_set_subaddress(
                           &ast_channel_dialed(pri->pvts[chanpos]->owner)->subaddress,
                           &e->ring.called_subaddress);
                        if (!e->ring.called_subaddress.type
                           && !ast_strlen_zero(
                              (char *) e->ring.called_subaddress.data)) {
                           /* NSAP */
                           pbx_builtin_setvar_helper(c, "CALLEDSUBADDR",
                              (char *) e->ring.called_subaddress.data);
                        }
                        ast_channel_unlock(c);
                     }
#else
                     if (!ast_strlen_zero(e->ring.callingsubaddr)) {
                        pbx_builtin_setvar_helper(c, "CALLINGSUBADDR", e->ring.callingsubaddr);
                     }
#endif /* !defined(HAVE_PRI_SUBADDR) */
                     if (e->ring.ani2 >= 0) {
                        snprintf(ani2str, sizeof(ani2str), "%d", e->ring.ani2);
                        pbx_builtin_setvar_helper(c, "ANI2", ani2str);
                     }

#ifdef SUPPORT_USERUSER
                     if (!ast_strlen_zero(e->ring.useruserinfo)) {
                        pbx_builtin_setvar_helper(c, "USERUSERINFO", e->ring.useruserinfo);
                     }
#endif

                     snprintf(calledtonstr, sizeof(calledtonstr), "%d", e->ring.calledplan);
                     pbx_builtin_setvar_helper(c, "CALLEDTON", calledtonstr);
                     ast_channel_lock(c);
                     ast_channel_dialed(c)->number.plan = e->ring.calledplan;
                     ast_channel_unlock(c);

                     if (e->ring.redirectingreason >= 0) {
                        /* This is now just a status variable.  Use REDIRECTING() dialplan function. */
                        pbx_builtin_setvar_helper(c, "PRIREDIRECTREASON", redirectingreason2str(e->ring.redirectingreason));
                     }
#if defined(HAVE_PRI_REVERSE_CHARGE)
                     pri->pvts[chanpos]->reverse_charging_indication = e->ring.reversecharge;
#endif
#if defined(HAVE_PRI_SETUP_KEYPAD)
                     ast_copy_string(pri->pvts[chanpos]->keypad_digits,
                        e->ring.keypad_digits,
                        sizeof(pri->pvts[chanpos]->keypad_digits));
#endif   /* defined(HAVE_PRI_SETUP_KEYPAD) */

                     sig_pri_handle_subcmds(pri, chanpos, e->e, e->ring.subcmds,
                        e->ring.call);

                     if (!pri->pvts[chanpos]->digital
                        && !pri->pvts[chanpos]->no_b_channel) {
                        /*
                         * Call has a channel.
                         * Indicate that we are providing dialtone.
                         */
                        pri->pvts[chanpos]->progress = 1;/* No need to send plain PROGRESS again. */
#ifdef HAVE_PRI_PROG_W_CAUSE
                        pri_progress_with_cause(pri->pri, e->ring.call,
                           PVT_TO_CHANNEL(pri->pvts[chanpos]), 1, -1);/* no cause at all */
#else
                        pri_progress(pri->pri, e->ring.call,
                           PVT_TO_CHANNEL(pri->pvts[chanpos]), 1);
#endif
                     }
                  }
                  if (c && !ast_pthread_create_detached(&threadid, NULL, pri_ss_thread, pri->pvts[chanpos])) {
                     ast_verb(3, "Accepting overlap call from '%s' to '%s' on channel %d/%d, span %d\n",
                        plancallingnum, S_OR(pri->pvts[chanpos]->exten, "<unspecified>"),
                        pri->pvts[chanpos]->logicalspan, pri->pvts[chanpos]->prioffset, pri->span);
                  } else {
                     ast_log(LOG_WARNING, "Unable to start PBX on channel %d/%d, span %d\n",
                        pri->pvts[chanpos]->logicalspan, pri->pvts[chanpos]->prioffset, pri->span);
                     if (c) {
                        /* Avoid deadlock while destroying channel */
                        sig_pri_unlock_private(pri->pvts[chanpos]);
                        ast_mutex_unlock(&pri->lock);
                        ast_hangup(c);
                        ast_mutex_lock(&pri->lock);
                     } else {
                        pri_hangup(pri->pri, e->ring.call, PRI_CAUSE_SWITCH_CONGESTION);
                        pri->pvts[chanpos]->call = NULL;
                        sig_pri_unlock_private(pri->pvts[chanpos]);
                        sig_pri_span_devstate_changed(pri);
                     }
                     break;
                  }
               } else {
                  /*
                   * Release the PRI lock while we create the channel so other
                   * threads can send D channel messages.  We must also release
                   * the private lock to prevent deadlock while creating the
                   * channel.
                   */
                  sig_pri_unlock_private(pri->pvts[chanpos]);
                  ast_mutex_unlock(&pri->lock);
                  c = sig_pri_new_ast_channel(pri->pvts[chanpos],
                     AST_STATE_RING, law, e->ring.ctype,
                     pri->pvts[chanpos]->exten, NULL);
                  ast_mutex_lock(&pri->lock);
                  sig_pri_lock_private(pri->pvts[chanpos]);
                  if (c) {
                     /*
                      * It is reasonably safe to set the following
                      * channel variables while the PRI and DAHDI private
                      * structures are locked.  The PBX has not been
                      * started yet and it is unlikely that any other task
                      * will do anything with the channel we have just
                      * created.
                      */
#if defined(HAVE_PRI_SUBADDR)
                     if (e->ring.calling.subaddress.valid) {
                        /* Set Calling Subaddress */
                        sig_pri_lock_owner(pri, chanpos);
                        sig_pri_set_subaddress(
                           &ast_channel_caller(pri->pvts[chanpos]->owner)->id.subaddress,
                           &e->ring.calling.subaddress);
                        if (!e->ring.calling.subaddress.type
                           && !ast_strlen_zero(
                              (char *) e->ring.calling.subaddress.data)) {
                           /* NSAP */
                           pbx_builtin_setvar_helper(c, "CALLINGSUBADDR",
                              (char *) e->ring.calling.subaddress.data);
                        }
                        ast_channel_unlock(c);
                     }
                     if (e->ring.called_subaddress.valid) {
                        /* Set Called Subaddress */
                        sig_pri_lock_owner(pri, chanpos);
                        sig_pri_set_subaddress(
                           &ast_channel_dialed(pri->pvts[chanpos]->owner)->subaddress,
                           &e->ring.called_subaddress);
                        if (!e->ring.called_subaddress.type
                           && !ast_strlen_zero(
                              (char *) e->ring.called_subaddress.data)) {
                           /* NSAP */
                           pbx_builtin_setvar_helper(c, "CALLEDSUBADDR",
                              (char *) e->ring.called_subaddress.data);
                        }
                        ast_channel_unlock(c);
                     }
#else
                     if (!ast_strlen_zero(e->ring.callingsubaddr)) {
                        pbx_builtin_setvar_helper(c, "CALLINGSUBADDR", e->ring.callingsubaddr);
                     }
#endif /* !defined(HAVE_PRI_SUBADDR) */
                     if (e->ring.ani2 >= 0) {
                        snprintf(ani2str, sizeof(ani2str), "%d", e->ring.ani2);
                        pbx_builtin_setvar_helper(c, "ANI2", ani2str);
                     }

#ifdef SUPPORT_USERUSER
                     if (!ast_strlen_zero(e->ring.useruserinfo)) {
                        pbx_builtin_setvar_helper(c, "USERUSERINFO", e->ring.useruserinfo);
                     }
#endif

                     if (e->ring.redirectingreason >= 0) {
                        /* This is now just a status variable.  Use REDIRECTING() dialplan function. */
                        pbx_builtin_setvar_helper(c, "PRIREDIRECTREASON", redirectingreason2str(e->ring.redirectingreason));
                     }
#if defined(HAVE_PRI_REVERSE_CHARGE)
                     pri->pvts[chanpos]->reverse_charging_indication = e->ring.reversecharge;
#endif
#if defined(HAVE_PRI_SETUP_KEYPAD)
                     ast_copy_string(pri->pvts[chanpos]->keypad_digits,
                        e->ring.keypad_digits,
                        sizeof(pri->pvts[chanpos]->keypad_digits));
#endif   /* defined(HAVE_PRI_SETUP_KEYPAD) */

                     snprintf(calledtonstr, sizeof(calledtonstr), "%d", e->ring.calledplan);
                     pbx_builtin_setvar_helper(c, "CALLEDTON", calledtonstr);
                     ast_channel_lock(c);
                     ast_channel_dialed(c)->number.plan = e->ring.calledplan;
                     ast_channel_unlock(c);

                     sig_pri_handle_subcmds(pri, chanpos, e->e, e->ring.subcmds,
                        e->ring.call);
                  }
                  if (c && !ast_pbx_start(c)) {
                     ast_verb(3, "Accepting call from '%s' to '%s' on channel %d/%d, span %d\n",
                        plancallingnum, pri->pvts[chanpos]->exten,
                        pri->pvts[chanpos]->logicalspan, pri->pvts[chanpos]->prioffset, pri->span);
                     sig_pri_set_echocanceller(pri->pvts[chanpos], 1);
                  } else {
                     ast_log(LOG_WARNING, "Unable to start PBX on channel %d/%d, span %d\n",
                        pri->pvts[chanpos]->logicalspan, pri->pvts[chanpos]->prioffset, pri->span);
                     if (c) {
                        /* Avoid deadlock while destroying channel */
                        sig_pri_unlock_private(pri->pvts[chanpos]);
                        ast_mutex_unlock(&pri->lock);
                        ast_hangup(c);
                        ast_mutex_lock(&pri->lock);
                     } else {
                        pri_hangup(pri->pri, e->ring.call, PRI_CAUSE_SWITCH_CONGESTION);
                        pri->pvts[chanpos]->call = NULL;
                        sig_pri_unlock_private(pri->pvts[chanpos]);
                        sig_pri_span_devstate_changed(pri);
                     }
                     break;
                  }
               }
            } else {
               ast_verb(3,
                  "Span %d: Extension %s@%s does not exist.  Rejecting call from '%s'.\n",
                  pri->span, pri->pvts[chanpos]->exten, pri->pvts[chanpos]->context,
                  pri->pvts[chanpos]->cid_num);
               pri_hangup(pri->pri, e->ring.call, PRI_CAUSE_UNALLOCATED);
               pri->pvts[chanpos]->call = NULL;
               pri->pvts[chanpos]->exten[0] = '\0';
               sig_pri_unlock_private(pri->pvts[chanpos]);
               sig_pri_span_devstate_changed(pri);
               break;
            }
            sig_pri_unlock_private(pri->pvts[chanpos]);
            break;
         case PRI_EVENT_RINGING:
            if (sig_pri_is_cis_call(e->ringing.channel)) {
               sig_pri_handle_cis_subcmds(pri, e->e, e->ringing.subcmds,
                  e->ringing.call);
               break;
            }
            chanpos = pri_find_fixup_principle(pri, e->ringing.channel,
               e->ringing.call);
            if (chanpos < 0) {
               break;
            }
            sig_pri_lock_private(pri->pvts[chanpos]);

            callid = func_pri_dchannel_chanpos_callid(pri, chanpos);

            sig_pri_handle_subcmds(pri, chanpos, e->e, e->ringing.subcmds,
               e->ringing.call);
            sig_pri_cc_generic_check(pri, chanpos, AST_CC_CCNR);
            sig_pri_set_echocanceller(pri->pvts[chanpos], 1);
            sig_pri_lock_owner(pri, chanpos);
            if (pri->pvts[chanpos]->owner) {
               ast_setstate(pri->pvts[chanpos]->owner, AST_STATE_RINGING);
               ast_channel_unlock(pri->pvts[chanpos]->owner);
            }
            pri_queue_control(pri, chanpos, AST_CONTROL_RINGING);
            if (pri->pvts[chanpos]->call_level < SIG_PRI_CALL_LEVEL_ALERTING) {
               pri->pvts[chanpos]->call_level = SIG_PRI_CALL_LEVEL_ALERTING;
            }

            if (!pri->pvts[chanpos]->progress
               && !pri->pvts[chanpos]->no_b_channel
#ifdef PRI_PROGRESS_MASK
               && (e->ringing.progressmask
                  & (PRI_PROG_CALL_NOT_E2E_ISDN | PRI_PROG_INBAND_AVAILABLE))
#else
               && e->ringing.progress == 8
#endif
               ) {
               /* Bring voice path up */
               pri_queue_control(pri, chanpos, AST_CONTROL_PROGRESS);
               pri->pvts[chanpos]->progress = 1;
               sig_pri_set_dialing(pri->pvts[chanpos], 0);
               sig_pri_open_media(pri->pvts[chanpos]);
            }

#ifdef SUPPORT_USERUSER
            if (!ast_strlen_zero(e->ringing.useruserinfo)) {
               struct ast_channel *owner;

               sig_pri_lock_owner(pri, chanpos);
               owner = pri->pvts[chanpos]->owner;
               if (owner) {
                  pbx_builtin_setvar_helper(owner, "USERUSERINFO",
                     e->ringing.useruserinfo);
                  ast_channel_unlock(owner);
               }
            }
#endif

            sig_pri_unlock_private(pri->pvts[chanpos]);
            break;
         case PRI_EVENT_PROGRESS:
            if (sig_pri_is_cis_call(e->proceeding.channel)) {
               sig_pri_handle_cis_subcmds(pri, e->e, e->proceeding.subcmds,
                  e->proceeding.call);
               break;
            }
            chanpos = pri_find_fixup_principle(pri, e->proceeding.channel,
               e->proceeding.call);
            if (chanpos < 0) {
               break;
            }
            sig_pri_lock_private(pri->pvts[chanpos]);

            callid = func_pri_dchannel_chanpos_callid(pri, chanpos);

            sig_pri_handle_subcmds(pri, chanpos, e->e, e->proceeding.subcmds,
               e->proceeding.call);

            if (e->proceeding.cause > -1) {
               if (pri->pvts[chanpos]->owner) {
                  snprintf(cause_str, sizeof(cause_str), "PRI PRI_EVENT_PROGRESS (%d)", e->proceeding.cause);
                  pri_queue_pvt_cause_data(pri, chanpos, cause_str, e->proceeding.cause);
               }

               ast_verb(3, "PROGRESS with cause code %d received\n", e->proceeding.cause);

               /* Work around broken, out of spec USER_BUSY cause in a progress message */
               if (e->proceeding.cause == AST_CAUSE_USER_BUSY) {
                  if (pri->pvts[chanpos]->owner) {
                     ast_verb(3, "PROGRESS with 'user busy' received, signaling AST_CONTROL_BUSY instead of AST_CONTROL_PROGRESS\n");

                     ast_channel_hangupcause_set(pri->pvts[chanpos]->owner, e->proceeding.cause);
                     pri_queue_control(pri, chanpos, AST_CONTROL_BUSY);
                  }
               }
            }

            if (!pri->pvts[chanpos]->progress
               && !pri->pvts[chanpos]->no_b_channel
#ifdef PRI_PROGRESS_MASK
               && (e->proceeding.progressmask
                  & (PRI_PROG_CALL_NOT_E2E_ISDN | PRI_PROG_INBAND_AVAILABLE))
#else
               && e->proceeding.progress == 8
#endif
               ) {
               /* Bring voice path up */
               ast_debug(1,
                  "Queuing frame from PRI_EVENT_PROGRESS on channel %d/%d span %d\n",
                  pri->pvts[chanpos]->logicalspan, pri->pvts[chanpos]->prioffset,
                  pri->span);
               pri_queue_control(pri, chanpos, AST_CONTROL_PROGRESS);
               pri->pvts[chanpos]->progress = 1;
               sig_pri_set_dialing(pri->pvts[chanpos], 0);
               sig_pri_open_media(pri->pvts[chanpos]);
            }
            sig_pri_unlock_private(pri->pvts[chanpos]);
            break;
         case PRI_EVENT_PROCEEDING:
            if (sig_pri_is_cis_call(e->proceeding.channel)) {
               sig_pri_handle_cis_subcmds(pri, e->e, e->proceeding.subcmds,
                  e->proceeding.call);
               break;
            }
            chanpos = pri_find_fixup_principle(pri, e->proceeding.channel,
               e->proceeding.call);
            if (chanpos < 0) {
               break;
            }
            sig_pri_lock_private(pri->pvts[chanpos]);

            callid = func_pri_dchannel_chanpos_callid(pri, chanpos);

            sig_pri_handle_subcmds(pri, chanpos, e->e, e->proceeding.subcmds,
               e->proceeding.call);
            if (pri->pvts[chanpos]->call_level < SIG_PRI_CALL_LEVEL_PROCEEDING) {
               pri->pvts[chanpos]->call_level = SIG_PRI_CALL_LEVEL_PROCEEDING;
               ast_debug(1,
                  "Queuing frame from PRI_EVENT_PROCEEDING on channel %d/%d span %d\n",
                  pri->pvts[chanpos]->logicalspan, pri->pvts[chanpos]->prioffset,
                  pri->span);
               pri_queue_control(pri, chanpos, AST_CONTROL_PROCEEDING);
            }
            if (!pri->pvts[chanpos]->progress
               && !pri->pvts[chanpos]->no_b_channel
#ifdef PRI_PROGRESS_MASK
               && (e->proceeding.progressmask
                  & (PRI_PROG_CALL_NOT_E2E_ISDN | PRI_PROG_INBAND_AVAILABLE))
#else
               && e->proceeding.progress == 8
#endif
               ) {
               /* Bring voice path up */
               pri_queue_control(pri, chanpos, AST_CONTROL_PROGRESS);
               pri->pvts[chanpos]->progress = 1;
               sig_pri_set_dialing(pri->pvts[chanpos], 0);
               sig_pri_open_media(pri->pvts[chanpos]);
            } else if (pri->inband_on_proceeding) {
               sig_pri_set_dialing(pri->pvts[chanpos], 0);
            }
            sig_pri_unlock_private(pri->pvts[chanpos]);
            break;
         case PRI_EVENT_FACILITY:
            if (!e->facility.call || sig_pri_is_cis_call(e->facility.channel)) {
               /* Event came in on the dummy channel or a CIS call. */
#if defined(HAVE_PRI_CALL_REROUTING)
               sig_pri_handle_cis_subcmds(pri, e->e, e->facility.subcmds,
                  e->facility.subcall);
#else
               sig_pri_handle_cis_subcmds(pri, e->e, e->facility.subcmds,
                  e->facility.call);
#endif   /* !defined(HAVE_PRI_CALL_REROUTING) */
               break;
            }
            chanpos = pri_find_principle_by_call(pri, e->facility.call);
            if (chanpos < 0) {
               ast_log(LOG_WARNING, "Span %d: Received facility for unknown call.\n",
                  pri->span);
               break;
            }
            sig_pri_lock_private(pri->pvts[chanpos]);

            callid = func_pri_dchannel_chanpos_callid(pri, chanpos);

#if defined(HAVE_PRI_CALL_REROUTING)
            sig_pri_handle_subcmds(pri, chanpos, e->e, e->facility.subcmds,
               e->facility.subcall);
#else
            sig_pri_handle_subcmds(pri, chanpos, e->e, e->facility.subcmds,
               e->facility.call);
#endif   /* !defined(HAVE_PRI_CALL_REROUTING) */
            sig_pri_unlock_private(pri->pvts[chanpos]);
            break;
         case PRI_EVENT_ANSWER:
            if (sig_pri_is_cis_call(e->answer.channel)) {
#if defined(HAVE_PRI_CALL_WAITING)
               /* Call is CIS so do normal CONNECT_ACKNOWLEDGE. */
               pri_connect_ack(pri->pri, e->answer.call, 0);
#endif   /* defined(HAVE_PRI_CALL_WAITING) */
               sig_pri_handle_cis_subcmds(pri, e->e, e->answer.subcmds,
                  e->answer.call);
               break;
            }
            chanpos = pri_find_fixup_principle(pri, e->answer.channel, e->answer.call);
            if (chanpos < 0) {
               break;
            }
#if defined(HAVE_PRI_CALL_WAITING)
            if (pri->pvts[chanpos]->is_call_waiting) {
               if (pri->pvts[chanpos]->no_b_channel) {
                  int new_chanpos;

                  /*
                   * Need to find a free channel now or
                   * kill the call with PRI_CAUSE_NORMAL_CIRCUIT_CONGESTION.
                   */
                  new_chanpos = pri_find_empty_chan(pri, 1);
                  if (0 <= new_chanpos) {
                     new_chanpos = pri_fixup_principle(pri, new_chanpos,
                        e->answer.call);
                  }
                  if (new_chanpos < 0) {
                     /*
                      * Either no channel was available or someone stole
                      * the channel!
                      */
                     ast_verb(3,
                        "Span %d: Channel not available for call waiting call.\n",
                        pri->span);
                     sig_pri_lock_private(pri->pvts[chanpos]);
                     sig_pri_handle_subcmds(pri, chanpos, e->e, e->answer.subcmds,
                        e->answer.call);
                     sig_pri_cc_generic_check(pri, chanpos, AST_CC_CCBS);
                     sig_pri_lock_owner(pri, chanpos);
                     if (pri->pvts[chanpos]->owner) {
                        ast_channel_hangupcause_set(pri->pvts[chanpos]->owner, PRI_CAUSE_NORMAL_CIRCUIT_CONGESTION);
                        switch (ast_channel_state(pri->pvts[chanpos]->owner)) {
                        case AST_STATE_BUSY:
                        case AST_STATE_UP:
                           ast_softhangup_nolock(pri->pvts[chanpos]->owner, AST_SOFTHANGUP_DEV);
                           break;
                        default:
                           pri_queue_control(pri, chanpos, AST_CONTROL_CONGESTION);
                           break;
                        }
                        ast_channel_unlock(pri->pvts[chanpos]->owner);
                     } else {
                        pri->pvts[chanpos]->is_call_waiting = 0;
                        ast_atomic_fetchadd_int(&pri->num_call_waiting_calls, -1);
                        pri_hangup(pri->pri, e->answer.call, PRI_CAUSE_NORMAL_CIRCUIT_CONGESTION);
                        pri->pvts[chanpos]->call = NULL;
                     }
                     sig_pri_unlock_private(pri->pvts[chanpos]);
                     sig_pri_span_devstate_changed(pri);
                     break;
                  }
                  chanpos = new_chanpos;
               }
               pri_connect_ack(pri->pri, e->answer.call, PVT_TO_CHANNEL(pri->pvts[chanpos]));
               sig_pri_span_devstate_changed(pri);
            } else {
               /* Call is normal so do normal CONNECT_ACKNOWLEDGE. */
               pri_connect_ack(pri->pri, e->answer.call, 0);
            }
#endif   /* defined(HAVE_PRI_CALL_WAITING) */
            sig_pri_lock_private(pri->pvts[chanpos]);

            callid = func_pri_dchannel_chanpos_callid(pri, chanpos);

#if defined(HAVE_PRI_CALL_WAITING)
            if (pri->pvts[chanpos]->is_call_waiting) {
               pri->pvts[chanpos]->is_call_waiting = 0;
               ast_atomic_fetchadd_int(&pri->num_call_waiting_calls, -1);
            }
#endif   /* defined(HAVE_PRI_CALL_WAITING) */
            sig_pri_handle_subcmds(pri, chanpos, e->e, e->answer.subcmds,
               e->answer.call);
            if (!ast_strlen_zero(pri->pvts[chanpos]->deferred_digits)) {
               /* We have some 'w' deferred digits to dial now. */
               ast_verb(3,
                  "Span %d: Channel %d/%d dialing deferred digit string: %s\n",
                  pri->span, pri->pvts[chanpos]->logicalspan,
                  pri->pvts[chanpos]->prioffset,
                  pri->pvts[chanpos]->deferred_digits);
               if (pri->pvts[chanpos]->call_level < SIG_PRI_CALL_LEVEL_DEFER_DIAL) {
                  pri->pvts[chanpos]->call_level = SIG_PRI_CALL_LEVEL_DEFER_DIAL;
               }
               sig_pri_dial_digits(pri->pvts[chanpos],
                  pri->pvts[chanpos]->deferred_digits);
            } else {
               if (pri->pvts[chanpos]->call_level < SIG_PRI_CALL_LEVEL_CONNECT) {
                  pri->pvts[chanpos]->call_level = SIG_PRI_CALL_LEVEL_CONNECT;
               }
               sig_pri_open_media(pri->pvts[chanpos]);
               pri_queue_control(pri, chanpos, AST_CONTROL_ANSWER);
               sig_pri_set_dialing(pri->pvts[chanpos], 0);
               /* Enable echo cancellation if it's not on already */
               sig_pri_set_echocanceller(pri->pvts[chanpos], 1);
            }

#ifdef SUPPORT_USERUSER
            if (!ast_strlen_zero(e->answer.useruserinfo)) {
               struct ast_channel *owner;

               sig_pri_lock_owner(pri, chanpos);
               owner = pri->pvts[chanpos]->owner;
               if (owner) {
                  pbx_builtin_setvar_helper(owner, "USERUSERINFO",
                     e->answer.useruserinfo);
                  ast_channel_unlock(owner);
               }
            }
#endif

            sig_pri_unlock_private(pri->pvts[chanpos]);
            break;
#if defined(HAVE_PRI_CALL_WAITING)
         case PRI_EVENT_CONNECT_ACK:
            if (sig_pri_is_cis_call(e->connect_ack.channel)) {
               sig_pri_handle_cis_subcmds(pri, e->e, e->connect_ack.subcmds,
                  e->connect_ack.call);
               break;
            }
            chanpos = pri_find_fixup_principle(pri, e->connect_ack.channel,
               e->connect_ack.call);
            if (chanpos < 0) {
               break;
            }

            sig_pri_lock_private(pri->pvts[chanpos]);

            callid = func_pri_dchannel_chanpos_callid(pri, chanpos);

            sig_pri_handle_subcmds(pri, chanpos, e->e, e->connect_ack.subcmds,
               e->connect_ack.call);
            sig_pri_open_media(pri->pvts[chanpos]);
            sig_pri_unlock_private(pri->pvts[chanpos]);
            sig_pri_span_devstate_changed(pri);
            break;
#endif   /* defined(HAVE_PRI_CALL_WAITING) */
         case PRI_EVENT_HANGUP:
            if (sig_pri_is_cis_call(e->hangup.channel)) {
               sig_pri_handle_cis_subcmds(pri, e->e, e->hangup.subcmds,
                  e->hangup.call);
               pri_hangup(pri->pri, e->hangup.call, e->hangup.cause);
               break;
            }
            chanpos = pri_find_principle_by_call(pri, e->hangup.call);
            if (chanpos < 0) {
               /*
                * Continue hanging up the call even though
                * we do not remember it (if we ever did).
                */
               pri_hangup(pri->pri, e->hangup.call, e->hangup.cause);
               break;
            }
            sig_pri_lock_private(pri->pvts[chanpos]);

            callid = func_pri_dchannel_chanpos_callid(pri, chanpos);

            sig_pri_handle_subcmds(pri, chanpos, e->e, e->hangup.subcmds,
               e->hangup.call);
            switch (e->hangup.cause) {
            case PRI_CAUSE_INVALID_CALL_REFERENCE:
               /*
                * The peer denies the existence of this call so we must
                * continue hanging it up and forget about it.
                */
               pri_hangup(pri->pri, e->hangup.call, e->hangup.cause);
               pri->pvts[chanpos]->call = NULL;
               break;
            default:
               break;
            }
            if (!pri->pvts[chanpos]->alreadyhungup) {
               /* we're calling here dahdi_hangup so once we get there we need to clear p->call after calling pri_hangup */
               pri->pvts[chanpos]->alreadyhungup = 1;
               switch (e->hangup.cause) {
               case PRI_CAUSE_USER_BUSY:
               case PRI_CAUSE_NORMAL_CIRCUIT_CONGESTION:
                  sig_pri_cc_generic_check(pri, chanpos, AST_CC_CCBS);
                  break;
               default:
                  break;
               }
               if (pri->pvts[chanpos]->owner) {
                  int do_hangup = 0;

                  snprintf(cause_str, sizeof(cause_str), "PRI PRI_EVENT_HANGUP (%d)", e->hangup.cause);
                  pri_queue_pvt_cause_data(pri, chanpos, cause_str, e->hangup.cause);

                  /* Queue a BUSY instead of a hangup if our cause is appropriate */
                  ast_channel_hangupcause_set(pri->pvts[chanpos]->owner, e->hangup.cause);
                  switch (ast_channel_state(pri->pvts[chanpos]->owner)) {
                  case AST_STATE_BUSY:
                  case AST_STATE_UP:
                     do_hangup = 1;
                     break;
                  default:
                     if (!pri->pvts[chanpos]->outgoing) {
                        /*
                         * The incoming call leg hung up before getting
                         * connected so just hangup the call.
                         */
                        do_hangup = 1;
                        break;
                     }
                     switch (e->hangup.cause) {
                     case PRI_CAUSE_USER_BUSY:
                        pri_queue_control(pri, chanpos, AST_CONTROL_BUSY);
                        break;
                     case PRI_CAUSE_CALL_REJECTED:
                     case PRI_CAUSE_NETWORK_OUT_OF_ORDER:
                     case PRI_CAUSE_NORMAL_CIRCUIT_CONGESTION:
                     case PRI_CAUSE_SWITCH_CONGESTION:
                     case PRI_CAUSE_DESTINATION_OUT_OF_ORDER:
                     case PRI_CAUSE_NORMAL_TEMPORARY_FAILURE:
                        pri_queue_control(pri, chanpos, AST_CONTROL_CONGESTION);
                        break;
                     default:
                        do_hangup = 1;
                        break;
                     }
                     break;
                  }

                  if (do_hangup) {
#if defined(HAVE_PRI_AOC_EVENTS)
                     if (detect_aoc_e_subcmd(e->hangup.subcmds)) {
                        /* If a AOC-E msg was sent during the release, we must use a
                         * AST_CONTROL_HANGUP frame to guarantee that frame gets read before hangup */
                        pri_queue_control(pri, chanpos, AST_CONTROL_HANGUP);
                     } else {
                        ast_channel_softhangup_internal_flag_add(pri->pvts[chanpos]->owner, AST_SOFTHANGUP_DEV);
                     }
#else
                     ast_channel_softhangup_internal_flag_add(pri->pvts[chanpos]->owner, AST_SOFTHANGUP_DEV);
#endif   /* defined(HAVE_PRI_AOC_EVENTS) */
                  }
               } else {
                  /*
                   * Continue hanging up the call even though
                   * we do not have an owner.
                   */
                  pri_hangup(pri->pri, pri->pvts[chanpos]->call, e->hangup.cause);
                  pri->pvts[chanpos]->call = NULL;
               }
               ast_verb(3, "Span %d: Channel %d/%d got hangup, cause %d\n",
                  pri->span, pri->pvts[chanpos]->logicalspan,
                  pri->pvts[chanpos]->prioffset, e->hangup.cause);
            } else {
               /* Continue hanging up the call. */
               pri_hangup(pri->pri, pri->pvts[chanpos]->call, e->hangup.cause);
               pri->pvts[chanpos]->call = NULL;
            }
#if defined(FORCE_RESTART_UNAVAIL_CHANS)
            if (e->hangup.cause == PRI_CAUSE_REQUESTED_CHAN_UNAVAIL
               && pri->sig != SIG_BRI_PTMP && !pri->resetting
               && pri->pvts[chanpos]->resetting == SIG_PRI_RESET_IDLE) {
               ast_verb(3,
                  "Span %d: Forcing restart of channel %d/%d since channel reported in use\n",
                  pri->span, pri->pvts[chanpos]->logicalspan,
                  pri->pvts[chanpos]->prioffset);
               pri->pvts[chanpos]->resetting = SIG_PRI_RESET_ACTIVE;
               pri_reset(pri->pri, PVT_TO_CHANNEL(pri->pvts[chanpos]));
            }
#endif   /* defined(FORCE_RESTART_UNAVAIL_CHANS) */
            if (e->hangup.aoc_units > -1)
               ast_verb(3, "Channel %d/%d, span %d received AOC-E charging %d unit%s\n",
                  pri->pvts[chanpos]->logicalspan, pri->pvts[chanpos]->prioffset, pri->span, (int)e->hangup.aoc_units, (e->hangup.aoc_units == 1) ? "" : "s");

#ifdef SUPPORT_USERUSER
            if (!ast_strlen_zero(e->hangup.useruserinfo)) {
               struct ast_channel *owner;

               sig_pri_lock_owner(pri, chanpos);
               owner = pri->pvts[chanpos]->owner;
               if (owner) {
                  pbx_builtin_setvar_helper(owner, "USERUSERINFO",
                     e->hangup.useruserinfo);
                  ast_channel_unlock(owner);
               }
            }
#endif

            sig_pri_unlock_private(pri->pvts[chanpos]);
            sig_pri_span_devstate_changed(pri);
            break;
         case PRI_EVENT_HANGUP_REQ:
            if (sig_pri_is_cis_call(e->hangup.channel)) {
               sig_pri_handle_cis_subcmds(pri, e->e, e->hangup.subcmds,
                  e->hangup.call);
               pri_hangup(pri->pri, e->hangup.call, e->hangup.cause);
               break;
            }
            chanpos = pri_find_principle_by_call(pri, e->hangup.call);
            if (chanpos < 0) {
               /*
                * Continue hanging up the call even though
                * we do not remember it (if we ever did).
                */
               pri_hangup(pri->pri, e->hangup.call, e->hangup.cause);
               break;
            }
            sig_pri_lock_private(pri->pvts[chanpos]);

            callid = func_pri_dchannel_chanpos_callid(pri, chanpos);

            sig_pri_handle_subcmds(pri, chanpos, e->e, e->hangup.subcmds,
               e->hangup.call);
#if defined(HAVE_PRI_CALL_HOLD)
            if (e->hangup.call_active && e->hangup.call_held
               && pri->hold_disconnect_transfer) {
               /* We are to transfer the call instead of simply hanging up. */
               sig_pri_unlock_private(pri->pvts[chanpos]);
               if (!sig_pri_attempt_transfer(pri, e->hangup.call_held, 1,
                  e->hangup.call_active, 0, NULL, NULL)) {
                  break;
               }
               sig_pri_lock_private(pri->pvts[chanpos]);
            }
#endif   /* defined(HAVE_PRI_CALL_HOLD) */
            switch (e->hangup.cause) {
            case PRI_CAUSE_USER_BUSY:
            case PRI_CAUSE_NORMAL_CIRCUIT_CONGESTION:
               sig_pri_cc_generic_check(pri, chanpos, AST_CC_CCBS);
               break;
            case PRI_CAUSE_INVALID_CALL_REFERENCE:
               /*
                * The peer denies the existence of this call so we must
                * continue hanging it up and forget about it.  We should not
                * get this cause here, but for completeness we will handle it
                * anyway.
                */
               pri_hangup(pri->pri, e->hangup.call, e->hangup.cause);
               pri->pvts[chanpos]->call = NULL;
               break;
            default:
               break;
            }
            if (pri->pvts[chanpos]->owner) {
               int do_hangup = 0;

               snprintf(cause_str, sizeof(cause_str), "PRI PRI_EVENT_HANGUP_REQ (%d)", e->hangup.cause);
               pri_queue_pvt_cause_data(pri, chanpos, cause_str, e->hangup.cause);

               ast_channel_hangupcause_set(pri->pvts[chanpos]->owner, e->hangup.cause);
               switch (ast_channel_state(pri->pvts[chanpos]->owner)) {
               case AST_STATE_BUSY:
               case AST_STATE_UP:
                  do_hangup = 1;
                  break;
               default:
                  if (!pri->pvts[chanpos]->outgoing) {
                     /*
                      * The incoming call leg hung up before getting
                      * connected so just hangup the call.
                      */
                     do_hangup = 1;
                     break;
                  }
                  switch (e->hangup.cause) {
                  case PRI_CAUSE_USER_BUSY:
                     pri_queue_control(pri, chanpos, AST_CONTROL_BUSY);
                     break;
                  case PRI_CAUSE_CALL_REJECTED:
                  case PRI_CAUSE_NETWORK_OUT_OF_ORDER:
                  case PRI_CAUSE_NORMAL_CIRCUIT_CONGESTION:
                  case PRI_CAUSE_SWITCH_CONGESTION:
                  case PRI_CAUSE_DESTINATION_OUT_OF_ORDER:
                  case PRI_CAUSE_NORMAL_TEMPORARY_FAILURE:
                     pri_queue_control(pri, chanpos, AST_CONTROL_CONGESTION);
                     break;
                  default:
                     do_hangup = 1;
                     break;
                  }
                  break;
               }

               if (do_hangup) {
#if defined(HAVE_PRI_AOC_EVENTS)
                  if (!pri->pvts[chanpos]->holding_aoce
                     && pri->aoce_delayhangup
                     && ast_bridged_channel(pri->pvts[chanpos]->owner)) {
                     sig_pri_send_aoce_termination_request(pri, chanpos,
                        pri_get_timer(pri->pri, PRI_TIMER_T305) / 2);
                  } else if (detect_aoc_e_subcmd(e->hangup.subcmds)) {
                     /* If a AOC-E msg was sent during the Disconnect, we must use a AST_CONTROL_HANGUP frame
                      * to guarantee that frame gets read before hangup */
                     pri_queue_control(pri, chanpos, AST_CONTROL_HANGUP);
                  } else {
                     ast_channel_softhangup_internal_flag_add(pri->pvts[chanpos]->owner, AST_SOFTHANGUP_DEV);
                  }
#else
                  ast_channel_softhangup_internal_flag_add(pri->pvts[chanpos]->owner, AST_SOFTHANGUP_DEV);
#endif   /* defined(HAVE_PRI_AOC_EVENTS) */
               }
               ast_verb(3, "Span %d: Channel %d/%d got hangup request, cause %d\n",
                  pri->span, pri->pvts[chanpos]->logicalspan,
                  pri->pvts[chanpos]->prioffset, e->hangup.cause);
            } else {
               /*
                * Continue hanging up the call even though
                * we do not have an owner.
                */
               pri_hangup(pri->pri, pri->pvts[chanpos]->call, e->hangup.cause);
               pri->pvts[chanpos]->call = NULL;
            }
#if defined(FORCE_RESTART_UNAVAIL_CHANS)
            if (e->hangup.cause == PRI_CAUSE_REQUESTED_CHAN_UNAVAIL
               && pri->sig != SIG_BRI_PTMP && !pri->resetting
               && pri->pvts[chanpos]->resetting == SIG_PRI_RESET_IDLE) {
               ast_verb(3,
                  "Span %d: Forcing restart of channel %d/%d since channel reported in use\n",
                  pri->span, pri->pvts[chanpos]->logicalspan,
                  pri->pvts[chanpos]->prioffset);
               pri->pvts[chanpos]->resetting = SIG_PRI_RESET_ACTIVE;
               pri_reset(pri->pri, PVT_TO_CHANNEL(pri->pvts[chanpos]));
            }
#endif   /* defined(FORCE_RESTART_UNAVAIL_CHANS) */

#ifdef SUPPORT_USERUSER
            if (!ast_strlen_zero(e->hangup.useruserinfo)) {
               struct ast_channel *owner;

               sig_pri_lock_owner(pri, chanpos);
               owner = pri->pvts[chanpos]->owner;
               if (owner) {
                  pbx_builtin_setvar_helper(owner, "USERUSERINFO",
                     e->hangup.useruserinfo);
                  ast_channel_unlock(owner);
               }
            }
#endif

            sig_pri_unlock_private(pri->pvts[chanpos]);
            sig_pri_span_devstate_changed(pri);
            break;
         case PRI_EVENT_HANGUP_ACK:
            if (sig_pri_is_cis_call(e->hangup.channel)) {
               sig_pri_handle_cis_subcmds(pri, e->e, e->hangup.subcmds,
                  e->hangup.call);
               break;
            }
            chanpos = pri_find_principle_by_call(pri, e->hangup.call);
            if (chanpos < 0) {
               break;
            }
            sig_pri_lock_private(pri->pvts[chanpos]);

            callid = func_pri_dchannel_chanpos_callid(pri, chanpos);

            pri->pvts[chanpos]->call = NULL;
            if (pri->pvts[chanpos]->owner) {
               ast_verb(3, "Span %d: Channel %d/%d got hangup ACK\n", pri->span,
                  pri->pvts[chanpos]->logicalspan, pri->pvts[chanpos]->prioffset);
            }
#ifdef SUPPORT_USERUSER
            if (!ast_strlen_zero(e->hangup.useruserinfo)) {
               struct ast_channel *owner;

               sig_pri_lock_owner(pri, chanpos);
               owner = pri->pvts[chanpos]->owner;
               if (owner) {
                  pbx_builtin_setvar_helper(owner, "USERUSERINFO",
                     e->hangup.useruserinfo);
                  ast_channel_unlock(owner);
               }
            }
#endif
            sig_pri_unlock_private(pri->pvts[chanpos]);
            sig_pri_span_devstate_changed(pri);
            break;
         case PRI_EVENT_CONFIG_ERR:
            ast_log(LOG_WARNING, "PRI Error on span %d: %s\n", pri->span, e->err.err);
            break;
         case PRI_EVENT_RESTART_ACK:
            chanpos = pri_find_principle(pri, e->restartack.channel, NULL);
            if (chanpos < 0) {
               /* Sometime switches (e.g. I421 / British Telecom) don't give us the
                  channel number, so we have to figure it out...  This must be why
                  everybody resets exactly a channel at a time. */
               for (x = 0; x < pri->numchans; x++) {
                  if (pri->pvts[x]
                     && pri->pvts[x]->resetting != SIG_PRI_RESET_IDLE) {
                     chanpos = x;
                     sig_pri_lock_private(pri->pvts[chanpos]);
                     ast_debug(1,
                        "Span %d: Assuming restart ack is for channel %d/%d\n",
                        pri->span, pri->pvts[chanpos]->logicalspan,
                        pri->pvts[chanpos]->prioffset);
                     if (pri->pvts[chanpos]->owner) {
                        ast_log(LOG_WARNING,
                           "Span %d: Got restart ack on channel %d/%d with owner\n",
                           pri->span, pri->pvts[chanpos]->logicalspan,
                           pri->pvts[chanpos]->prioffset);
                        ast_channel_softhangup_internal_flag_add(pri->pvts[chanpos]->owner, AST_SOFTHANGUP_DEV);
                     }
                     pri->pvts[chanpos]->resetting = SIG_PRI_RESET_IDLE;
                     ast_verb(3,
                        "Span %d: Channel %d/%d successfully restarted\n",
                        pri->span, pri->pvts[chanpos]->logicalspan,
                        pri->pvts[chanpos]->prioffset);
                     sig_pri_unlock_private(pri->pvts[chanpos]);
                     if (pri->resetting)
                        pri_check_restart(pri);
                     break;
                  }
               }
               if (chanpos < 0) {
                  ast_log(LOG_WARNING,
                     "Span %d: Restart ACK on strange channel %d/%d\n",
                     pri->span, PRI_SPAN(e->restartack.channel),
                     PRI_CHANNEL(e->restartack.channel));
               }
            } else {
               sig_pri_lock_private(pri->pvts[chanpos]);
               if (pri->pvts[chanpos]->resetting == SIG_PRI_RESET_IDLE) {
                  /* The channel is not in the resetting state. */
                  ast_debug(1,
                     "Span %d: Unexpected or late restart ack on channel %d/%d (Ignoring)\n",
                     pri->span, pri->pvts[chanpos]->logicalspan,
                     pri->pvts[chanpos]->prioffset);
                  sig_pri_unlock_private(pri->pvts[chanpos]);
                  break;
               }
               if (pri->pvts[chanpos]->owner) {
                  ast_log(LOG_WARNING,
                     "Span %d: Got restart ack on channel %d/%d with owner\n",
                     pri->span, pri->pvts[chanpos]->logicalspan,
                     pri->pvts[chanpos]->prioffset);
                  ast_channel_softhangup_internal_flag_add(pri->pvts[chanpos]->owner, AST_SOFTHANGUP_DEV);
               }
               pri->pvts[chanpos]->resetting = SIG_PRI_RESET_IDLE;
               ast_verb(3,
                  "Span %d: Channel %d/%d successfully restarted\n",
                  pri->span, pri->pvts[chanpos]->logicalspan,
                  pri->pvts[chanpos]->prioffset);
               sig_pri_unlock_private(pri->pvts[chanpos]);
               if (pri->resetting)
                  pri_check_restart(pri);
            }
            break;
         case PRI_EVENT_SETUP_ACK:
            if (sig_pri_is_cis_call(e->setup_ack.channel)) {
               sig_pri_handle_cis_subcmds(pri, e->e, e->setup_ack.subcmds,
                  e->setup_ack.call);
               break;
            }
            chanpos = pri_find_fixup_principle(pri, e->setup_ack.channel,
               e->setup_ack.call);
            if (chanpos < 0) {
               break;
            }
            sig_pri_lock_private(pri->pvts[chanpos]);

            callid = func_pri_dchannel_chanpos_callid(pri, chanpos);

            sig_pri_handle_subcmds(pri, chanpos, e->e, e->setup_ack.subcmds,
               e->setup_ack.call);
            if (pri->pvts[chanpos]->call_level < SIG_PRI_CALL_LEVEL_OVERLAP) {
               pri->pvts[chanpos]->call_level = SIG_PRI_CALL_LEVEL_OVERLAP;
            }

            /* Send any queued digits */
            len = strlen(pri->pvts[chanpos]->dialdest);
            for (x = 0; x < len; ++x) {
               ast_debug(1, "Sending pending digit '%c'\n", pri->pvts[chanpos]->dialdest[x]);
               pri_information(pri->pri, pri->pvts[chanpos]->call,
                  pri->pvts[chanpos]->dialdest[x]);
            }

            if (!pri->pvts[chanpos]->progress
               && (pri->overlapdial & DAHDI_OVERLAPDIAL_OUTGOING)
               && !pri->pvts[chanpos]->digital
               && !pri->pvts[chanpos]->no_b_channel) {
               /*
                * Call has a channel.
                * Indicate for overlap dialing that dialtone may be present.
                */
               pri_queue_control(pri, chanpos, AST_CONTROL_PROGRESS);
               pri->pvts[chanpos]->progress = 1;/* Claim to have seen inband-information */
               sig_pri_set_dialing(pri->pvts[chanpos], 0);
               sig_pri_open_media(pri->pvts[chanpos]);
            }
            sig_pri_unlock_private(pri->pvts[chanpos]);
            break;
         case PRI_EVENT_NOTIFY:
            if (sig_pri_is_cis_call(e->notify.channel)) {
#if defined(HAVE_PRI_CALL_HOLD)
               sig_pri_handle_cis_subcmds(pri, e->e, e->notify.subcmds,
                  e->notify.call);
#else
               sig_pri_handle_cis_subcmds(pri, e->e, e->notify.subcmds, NULL);
#endif   /* !defined(HAVE_PRI_CALL_HOLD) */
               break;
            }
#if defined(HAVE_PRI_CALL_HOLD)
            chanpos = pri_find_principle_by_call(pri, e->notify.call);
            if (chanpos < 0) {
               ast_log(LOG_WARNING, "Span %d: Received NOTIFY for unknown call.\n",
                  pri->span);
               break;
            }
#else
            /*
             * This version of libpri does not supply a call pointer for
             * this message.  We are just going to have to trust that the
             * correct principle is found.
             */
            chanpos = pri_find_principle(pri, e->notify.channel, NULL);
            if (chanpos < 0) {
               ast_log(LOG_WARNING, "Received NOTIFY on unconfigured channel %d/%d span %d\n",
                  PRI_SPAN(e->notify.channel), PRI_CHANNEL(e->notify.channel), pri->span);
               break;
            }
#endif   /* !defined(HAVE_PRI_CALL_HOLD) */
            sig_pri_lock_private(pri->pvts[chanpos]);

            callid = func_pri_dchannel_chanpos_callid(pri, chanpos);

#if defined(HAVE_PRI_CALL_HOLD)
            sig_pri_handle_subcmds(pri, chanpos, e->e, e->notify.subcmds,
               e->notify.call);
#else
            sig_pri_handle_subcmds(pri, chanpos, e->e, e->notify.subcmds, NULL);
#endif   /* !defined(HAVE_PRI_CALL_HOLD) */
            switch (e->notify.info) {
            case PRI_NOTIFY_REMOTE_HOLD:
               if (!pri->discardremoteholdretrieval) {
                  pri_queue_control(pri, chanpos, AST_CONTROL_HOLD);
               }
               break;
            case PRI_NOTIFY_REMOTE_RETRIEVAL:
               if (!pri->discardremoteholdretrieval) {
                  pri_queue_control(pri, chanpos, AST_CONTROL_UNHOLD);
               }
               break;
            }
            sig_pri_unlock_private(pri->pvts[chanpos]);
            break;
#if defined(HAVE_PRI_CALL_HOLD)
         case PRI_EVENT_HOLD:
            /* We should not be getting any CIS calls with this message type. */
            if (sig_pri_handle_hold(pri, e)) {
               pri_hold_rej(pri->pri, e->hold.call,
                  PRI_CAUSE_RESOURCE_UNAVAIL_UNSPECIFIED);
            } else {
               pri_hold_ack(pri->pri, e->hold.call);
            }
            break;
#endif   /* defined(HAVE_PRI_CALL_HOLD) */
#if defined(HAVE_PRI_CALL_HOLD)
         case PRI_EVENT_HOLD_ACK:
            /* We should not be getting any CIS calls with this message type. */
            sig_pri_handle_hold_ack(pri, e);
            break;
#endif   /* defined(HAVE_PRI_CALL_HOLD) */
#if defined(HAVE_PRI_CALL_HOLD)
         case PRI_EVENT_HOLD_REJ:
            /* We should not be getting any CIS calls with this message type. */
            sig_pri_handle_hold_rej(pri, e);
            break;
#endif   /* defined(HAVE_PRI_CALL_HOLD) */
#if defined(HAVE_PRI_CALL_HOLD)
         case PRI_EVENT_RETRIEVE:
            /* We should not be getting any CIS calls with this message type. */
            sig_pri_handle_retrieve(pri, e);
            break;
#endif   /* defined(HAVE_PRI_CALL_HOLD) */
#if defined(HAVE_PRI_CALL_HOLD)
         case PRI_EVENT_RETRIEVE_ACK:
            /* We should not be getting any CIS calls with this message type. */
            sig_pri_handle_retrieve_ack(pri, e);
            break;
#endif   /* defined(HAVE_PRI_CALL_HOLD) */
#if defined(HAVE_PRI_CALL_HOLD)
         case PRI_EVENT_RETRIEVE_REJ:
            /* We should not be getting any CIS calls with this message type. */
            sig_pri_handle_retrieve_rej(pri, e);
            break;
#endif   /* defined(HAVE_PRI_CALL_HOLD) */
         default:
            ast_debug(1, "Span: %d Unhandled event: %s(%d)\n",
               pri->span, pri_event2str(e->e), e->e);
            break;
         }

         /* If a callid was set, we need to deref it and remove it from thread storage. */
         if (callid) {
            callid = ast_callid_unref(callid);
            ast_callid_threadassoc_remove();
         }
      }
      ast_mutex_unlock(&pri->lock);
   }
   /* Never reached */
   return NULL;
}

/*!
 * \brief Output AMI show spans response events for the given PRI span.
 * \since 10.0
 *
 * \param show_cmd AMI command name
 * \param s AMI session to output span information.
 * \param pri PRI span control structure.
 * \param dchannels Array of D channel channel numbers.
 * \param action_id Action ID line to use.
 *
 * \return Number of D channels on this span.
 */
int sig_pri_ami_show_spans(struct mansession *s, const char *show_cmd, struct sig_pri_span *pri, const int *dchannels, const char *action_id)
{
   int count;
   int x;

   count = 0;
   for (x = 0; x < ARRAY_LEN(pri->dchans); ++x) {
      if (pri->dchans[x]) {
         ++count;

         astman_append(s,
            "Event: %s\r\n"
            "Span: %d\r\n"
            "DChannel: %d\r\n"
            "Order: %s\r\n"
            "Active: %s\r\n"
            "Alarm: %s\r\n"
            "Up: %s\r\n"
            "%s"
            "\r\n",
            show_cmd,
            pri->span,
            dchannels[x],
            pri_order(x),
            (pri->dchans[x] == pri->pri) ? "Yes" : "No",
            (pri->dchanavail[x] & DCHAN_NOTINALARM) ? "No" : "Yes",
            (pri->dchanavail[x] & DCHAN_UP) ? "Yes" : "No",
            action_id
            );
      }
   }
   return count;
}

void sig_pri_init_pri(struct sig_pri_span *pri)
{
   int i;

   memset(pri, 0, sizeof(*pri));

   ast_mutex_init(&pri->lock);

   pri->master = AST_PTHREADT_NULL;
   for (i = 0; i < SIG_PRI_NUM_DCHANS; i++)
      pri->fds[i] = -1;
}

int sig_pri_hangup(struct sig_pri_chan *p, struct ast_channel *ast)
{
   ast_debug(1, "%s %d\n", __FUNCTION__, p->channel);
   if (!ast_channel_tech_pvt(ast)) {
      ast_log(LOG_WARNING, "Asked to hangup channel not connected\n");
      return 0;
   }

   sig_pri_set_outgoing(p, 0);
   sig_pri_set_digital(p, 0); /* push up to parent for EC*/
#if defined(HAVE_PRI_CALL_WAITING)
   if (p->is_call_waiting) {
      p->is_call_waiting = 0;
      ast_atomic_fetchadd_int(&p->pri->num_call_waiting_calls, -1);
   }
#endif   /* defined(HAVE_PRI_CALL_WAITING) */
   p->call_level = SIG_PRI_CALL_LEVEL_IDLE;
   p->progress = 0;
   p->cid_num[0] = '\0';
   p->cid_subaddr[0] = '\0';
   p->cid_name[0] = '\0';
   p->user_tag[0] = '\0';
   p->exten[0] = '\0';
   sig_pri_set_dialing(p, 0);

   /* Make sure we really have a call */
   pri_grab(p, p->pri);
   sig_pri_moh_fsm_event(ast, p, SIG_PRI_MOH_EVENT_RESET);
   if (p->call) {
#if defined(SUPPORT_USERUSER)
      const char *useruser = pbx_builtin_getvar_helper(ast, "USERUSERINFO");

      if (!ast_strlen_zero(useruser)) {
         pri_call_set_useruser(p->call, useruser);
      }
#endif   /* defined(SUPPORT_USERUSER) */

#if defined(HAVE_PRI_AOC_EVENTS)
      if (p->holding_aoce) {
         pri_aoc_e_send(p->pri->pri, p->call, &p->aoc_e);
      }
#endif   /* defined(HAVE_PRI_AOC_EVENTS) */

      if (p->alreadyhungup) {
         ast_debug(1, "Already hungup...  Calling hangup once, and clearing call\n");

         pri_hangup(p->pri->pri, p->call, -1);
         p->call = NULL;
      } else {
         const char *cause = pbx_builtin_getvar_helper(ast,"PRI_CAUSE");
         int icause = ast_channel_hangupcause(ast) ? ast_channel_hangupcause(ast) : -1;

         p->alreadyhungup = 1;
         if (!ast_strlen_zero(cause)) {
            if (atoi(cause)) {
               icause = atoi(cause);
            }
         }
         ast_debug(1,
            "Not yet hungup...  Calling hangup with cause %d, and clearing call\n",
            icause);

         pri_hangup(p->pri->pri, p->call, icause);
      }
   }
#if defined(HAVE_PRI_AOC_EVENTS)
   p->aoc_s_request_invoke_id_valid = 0;
   p->holding_aoce = 0;
   p->waiting_for_aoce = 0;
#endif   /* defined(HAVE_PRI_AOC_EVENTS) */

   p->allocated = 0;
   p->owner = NULL;

   sig_pri_span_devstate_changed(p->pri);
   pri_rel(p->pri);
   return 0;
}

/*!
 * \brief Extract the called number and subaddress from the dial string.
 * \since 1.8
 *
 * \param p sig_pri channel structure.
 * \param rdest Dial string buffer to extract called number and subaddress.
 * \param called Buffer to fill with extracted <number>[:<subaddress>]
 * \param called_buff_size Size of buffer to fill.
 *
 * \note Parsing must remain in sync with sig_pri_call().
 *
 * \return Nothing
 */
void sig_pri_extract_called_num_subaddr(struct sig_pri_chan *p, const char *rdest, char *called, size_t called_buff_size)
{
   char *dial;
   char *number;
   char *subaddr;
   AST_DECLARE_APP_ARGS(args,
      AST_APP_ARG(group);  /* channel/group token */
      AST_APP_ARG(ext); /* extension token */
      //AST_APP_ARG(opts); /* options token */
      AST_APP_ARG(other);  /* Any remining unused arguments */
   );

   /* Get private copy of dial string and break it up. */
   dial = ast_strdupa(rdest);
   AST_NONSTANDARD_APP_ARGS(args, dial, '/');

   number = args.ext;
   if (!number) {
      number = "";
   }

   /* Find and extract dialed_subaddress */
   subaddr = strchr(number, ':');
   if (subaddr) {
      *subaddr++ = '\0';

      /* Skip subaddress type prefix. */
      switch (*subaddr) {
      case 'U':
      case 'u':
      case 'N':
      case 'n':
         ++subaddr;
         break;
      default:
         break;
      }
   }

   /* Skip type-of-number/dial-plan prefix characters. */
   if (strlen(number) < p->stripmsd) {
      number = "";
   } else {
      char *deferred;

      number += p->stripmsd;
      deferred = strchr(number, 'w');
      if (deferred) {
         /* Remove any 'w' deferred digits. */
         *deferred = '\0';
      }
      while (isalpha(*number)) {
         ++number;
      }
   }

   /* Fill buffer with extracted number and subaddress. */
   if (ast_strlen_zero(subaddr)) {
      /* Put in called number only since there is no subaddress. */
      snprintf(called, called_buff_size, "%s", number);
   } else {
      /* Put in called number and subaddress. */
      snprintf(called, called_buff_size, "%s:%s", number, subaddr);
   }
}

enum SIG_PRI_CALL_OPT_FLAGS {
   OPT_KEYPAD =         (1 << 0),
   OPT_REVERSE_CHARGE = (1 << 1),   /* Collect call */
   OPT_AOC_REQUEST =    (1 << 2),   /* AOC Request */
};
enum SIG_PRI_CALL_OPT_ARGS {
   OPT_ARG_KEYPAD = 0,
   OPT_ARG_AOC_REQUEST,

   /* note: this entry _MUST_ be the last one in the enum */
   OPT_ARG_ARRAY_SIZE,
};

AST_APP_OPTIONS(sig_pri_call_opts, BEGIN_OPTIONS
   AST_APP_OPTION_ARG('K', OPT_KEYPAD, OPT_ARG_KEYPAD),
   AST_APP_OPTION('R', OPT_REVERSE_CHARGE),
   AST_APP_OPTION_ARG('A', OPT_AOC_REQUEST, OPT_ARG_AOC_REQUEST),
END_OPTIONS);

/*! \note Parsing must remain in sync with sig_pri_extract_called_num_subaddr(). */
int sig_pri_call(struct sig_pri_chan *p, struct ast_channel *ast, const char *rdest, int timeout, int layer1)
{
   char dest[256]; /* must be same length as p->dialdest */
   struct ast_party_subaddress dialed_subaddress; /* Called subaddress */
   struct pri_sr *sr;
   char *c, *l, *n, *s;
#ifdef SUPPORT_USERUSER
   const char *useruser;
#endif
   int core_id;
   int pridialplan;
   int dp_strip;
   int prilocaldialplan;
   int ldp_strip;
   int exclusive;
#if defined(HAVE_PRI_SETUP_KEYPAD)
   const char *keypad;
#endif   /* defined(HAVE_PRI_SETUP_KEYPAD) */
   AST_DECLARE_APP_ARGS(args,
      AST_APP_ARG(group);  /* channel/group token */
      AST_APP_ARG(ext); /* extension token */
      AST_APP_ARG(opts);   /* options token */
      AST_APP_ARG(other);  /* Any remining unused arguments */
   );
   struct ast_flags opts;
   char *opt_args[OPT_ARG_ARRAY_SIZE];
   struct ast_party_id connected_id = ast_channel_connected_effective_id(ast);

   ast_debug(1, "CALLER NAME: %s NUM: %s\n",
      S_COR(connected_id.name.valid, connected_id.name.str, ""),
      S_COR(connected_id.number.valid, connected_id.number.str, ""));

   if (!p->pri) {
      ast_log(LOG_ERROR, "Could not find pri on channel %d\n", p->channel);
      return -1;
   }

   if ((ast_channel_state(ast) != AST_STATE_DOWN) && (ast_channel_state(ast) != AST_STATE_RESERVED)) {
      ast_log(LOG_WARNING, "sig_pri_call called on %s, neither down nor reserved\n", ast_channel_name(ast));
      return -1;
   }

   p->dialdest[0] = '\0';
   sig_pri_set_outgoing(p, 1);

   ast_copy_string(dest, rdest, sizeof(dest));
   AST_NONSTANDARD_APP_ARGS(args, dest, '/');
   if (ast_app_parse_options(sig_pri_call_opts, &opts, opt_args, args.opts)) {
      /* General invalid option syntax. */
      return -1;
   }

   c = args.ext;
   if (!c) {
      c = "";
   }

   /* setup dialed_subaddress if found */
   ast_party_subaddress_init(&dialed_subaddress);
   s = strchr(c, ':');
   if (s) {
      *s = '\0';
      s++;
      /* prefix */
      /* 'n' = NSAP */
      /* 'u' = User Specified */
      /* Default = NSAP */
      switch (*s) {
      case 'U':
      case 'u':
         s++;
         dialed_subaddress.type = 2;
         break;
      case 'N':
      case 'n':
         s++;
         /* default already covered with ast_party_subaddress_init */
         break;
      }
      dialed_subaddress.str = s;
      dialed_subaddress.valid = 1;
   }

   l = NULL;
   n = NULL;
   if (!p->hidecallerid) {
      if (connected_id.number.valid) {
         /* If we get to the end of this loop without breaking, there's no
          * calleridnum.  This is done instead of testing for "unknown" or
          * the thousands of other ways that the calleridnum could be
          * invalid. */
         for (l = connected_id.number.str; l && *l; l++) {
            if (strchr("0123456789", *l)) {
               l = connected_id.number.str;
               break;
            }
         }
      } else {
         l = NULL;
      }
      if (!p->hidecalleridname) {
         n = connected_id.name.valid ? connected_id.name.str : NULL;
      }
   }

   if (strlen(c) < p->stripmsd) {
      ast_log(LOG_WARNING, "Number '%s' is shorter than stripmsd (%d)\n", c, p->stripmsd);
      return -1;
   }

   /* Extract any 'w' deferred digits. */
   s = strchr(c + p->stripmsd, 'w');
   if (s) {
      *s++ = '\0';
      ast_copy_string(p->deferred_digits, s, sizeof(p->deferred_digits));
      /*
       * Since we have a 'w', this means that there will not be any
       * more normal dialed digits.  Therefore, the sending complete
       * ie needs to be sent with any normal digits.
       */
   } else {
      p->deferred_digits[0] = '\0';
   }

   pri_grab(p, p->pri);
   if (!(p->call = pri_new_call(p->pri->pri))) {
      ast_log(LOG_WARNING, "Unable to create call on channel %d\n", p->channel);
      pri_rel(p->pri);
      return -1;
   }
   if (!(sr = pri_sr_new())) {
      ast_log(LOG_WARNING, "Failed to allocate setup request on channel %d\n",
         p->channel);
      pri_destroycall(p->pri->pri, p->call);
      p->call = NULL;
      pri_rel(p->pri);
      return -1;
   }

   sig_pri_set_digital(p, IS_DIGITAL(ast_channel_transfercapability(ast)));   /* push up to parent for EC */

#if defined(HAVE_PRI_CALL_WAITING)
   if (p->is_call_waiting) {
      /*
       * Indicate that this is a call waiting call.
       * i.e., Normal call but with no B channel.
       */
      pri_sr_set_channel(sr, 0, 0, 1);
   } else
#endif   /* defined(HAVE_PRI_CALL_WAITING) */
   {
      /* Should the picked channel be used exclusively? */
      if (p->priexclusive || p->pri->nodetype == PRI_NETWORK) {
         exclusive = 1;
      } else {
         exclusive = 0;
      }
      pri_sr_set_channel(sr, PVT_TO_CHANNEL(p), exclusive, 1);
   }

   pri_sr_set_bearer(sr, p->digital ? PRI_TRANS_CAP_DIGITAL : ast_channel_transfercapability(ast),
      (p->digital ? -1 : layer1));

   if (p->pri->facilityenable)
      pri_facility_enable(p->pri->pri);

   ast_verb(3, "Requested transfer capability: 0x%.2x - %s\n", ast_channel_transfercapability(ast), ast_transfercapability2str(ast_channel_transfercapability(ast)));
   dp_strip = 0;
   pridialplan = p->pri->dialplan - 1;
   if (pridialplan == -2 || pridialplan == -3) { /* compute dynamically */
      if (strncmp(c + p->stripmsd, p->pri->internationalprefix, strlen(p->pri->internationalprefix)) == 0) {
         if (pridialplan == -2) {
            dp_strip = strlen(p->pri->internationalprefix);
         }
         pridialplan = PRI_INTERNATIONAL_ISDN;
      } else if (strncmp(c + p->stripmsd, p->pri->nationalprefix, strlen(p->pri->nationalprefix)) == 0) {
         if (pridialplan == -2) {
            dp_strip = strlen(p->pri->nationalprefix);
         }
         pridialplan = PRI_NATIONAL_ISDN;
      } else {
         pridialplan = PRI_LOCAL_ISDN;
      }
   }
   while (c[p->stripmsd] > '9' && c[p->stripmsd] != '*' && c[p->stripmsd] != '#') {
      switch (c[p->stripmsd]) {
      case 'U':
         pridialplan = (PRI_TON_UNKNOWN << 4) | (pridialplan & 0xf);
         break;
      case 'I':
         pridialplan = (PRI_TON_INTERNATIONAL << 4) | (pridialplan & 0xf);
         break;
      case 'N':
         pridialplan = (PRI_TON_NATIONAL << 4) | (pridialplan & 0xf);
         break;
      case 'L':
         pridialplan = (PRI_TON_NET_SPECIFIC << 4) | (pridialplan & 0xf);
         break;
      case 'S':
         pridialplan = (PRI_TON_SUBSCRIBER << 4) | (pridialplan & 0xf);
         break;
      case 'V':
         pridialplan = (PRI_TON_ABBREVIATED << 4) | (pridialplan & 0xf);
         break;
      case 'R':
         pridialplan = (PRI_TON_RESERVED << 4) | (pridialplan & 0xf);
         break;
      case 'u':
         pridialplan = PRI_NPI_UNKNOWN | (pridialplan & 0xf0);
         break;
      case 'e':
         pridialplan = PRI_NPI_E163_E164 | (pridialplan & 0xf0);
         break;
      case 'x':
         pridialplan = PRI_NPI_X121 | (pridialplan & 0xf0);
         break;
      case 'f':
         pridialplan = PRI_NPI_F69 | (pridialplan & 0xf0);
         break;
      case 'n':
         pridialplan = PRI_NPI_NATIONAL | (pridialplan & 0xf0);
         break;
      case 'p':
         pridialplan = PRI_NPI_PRIVATE | (pridialplan & 0xf0);
         break;
      case 'r':
         pridialplan = PRI_NPI_RESERVED | (pridialplan & 0xf0);
         break;
      default:
         if (isalpha(c[p->stripmsd])) {
            ast_log(LOG_WARNING, "Unrecognized pridialplan %s modifier: %c\n",
               c[p->stripmsd] > 'Z' ? "NPI" : "TON", c[p->stripmsd]);
         }
         break;
      }
      c++;
   }
#if defined(HAVE_PRI_SETUP_KEYPAD)
   if (ast_test_flag(&opts, OPT_KEYPAD)
      && !ast_strlen_zero(opt_args[OPT_ARG_KEYPAD])) {
      /* We have a keypad facility digits option with digits. */
      keypad = opt_args[OPT_ARG_KEYPAD];
      pri_sr_set_keypad_digits(sr, keypad);
   } else {
      keypad = NULL;
   }
   if (!keypad || !ast_strlen_zero(c + p->stripmsd + dp_strip))
#endif   /* defined(HAVE_PRI_SETUP_KEYPAD) */
   {
      pri_sr_set_called(sr, c + p->stripmsd + dp_strip, pridialplan, s ? 1 : 0);
   }

#if defined(HAVE_PRI_SUBADDR)
   if (dialed_subaddress.valid) {
      struct pri_party_subaddress subaddress;

      memset(&subaddress, 0, sizeof(subaddress));
      sig_pri_party_subaddress_from_ast(&subaddress, &dialed_subaddress);
      pri_sr_set_called_subaddress(sr, &subaddress);
   }
#endif   /* defined(HAVE_PRI_SUBADDR) */
#if defined(HAVE_PRI_REVERSE_CHARGE)
   if (ast_test_flag(&opts, OPT_REVERSE_CHARGE)) {
      pri_sr_set_reversecharge(sr, PRI_REVERSECHARGE_REQUESTED);
   }
#endif   /* defined(HAVE_PRI_REVERSE_CHARGE) */
#if defined(HAVE_PRI_AOC_EVENTS)
   if (ast_test_flag(&opts, OPT_AOC_REQUEST)
      && !ast_strlen_zero(opt_args[OPT_ARG_AOC_REQUEST])) {
      if (strchr(opt_args[OPT_ARG_AOC_REQUEST], 's')) {
         pri_sr_set_aoc_charging_request(sr, PRI_AOC_REQUEST_S);
      }
      if (strchr(opt_args[OPT_ARG_AOC_REQUEST], 'd')) {
         pri_sr_set_aoc_charging_request(sr, PRI_AOC_REQUEST_D);
      }
      if (strchr(opt_args[OPT_ARG_AOC_REQUEST], 'e')) {
         pri_sr_set_aoc_charging_request(sr, PRI_AOC_REQUEST_E);
      }
   }
#endif   /* defined(HAVE_PRI_AOC_EVENTS) */

   /* Setup the user tag for party id's from this device for this call. */
   if (p->pri->append_msn_to_user_tag) {
      snprintf(p->user_tag, sizeof(p->user_tag), "%s_%s", p->pri->initial_user_tag,
         p->pri->nodetype == PRI_NETWORK
            ? c + p->stripmsd + dp_strip
            : S_COR(ast_channel_connected(ast)->id.number.valid,
               ast_channel_connected(ast)->id.number.str, ""));
   } else {
      ast_copy_string(p->user_tag, p->pri->initial_user_tag, sizeof(p->user_tag));
   }

   /*
    * Replace the caller id tag from the channel creation
    * with the actual tag value.
    */
   ast_free(ast_channel_caller(ast)->id.tag);
   ast_channel_caller(ast)->id.tag = ast_strdup(p->user_tag);

   ldp_strip = 0;
   prilocaldialplan = p->pri->localdialplan - 1;
   if ((l != NULL) && (prilocaldialplan == -2 || prilocaldialplan == -3)) { /* compute dynamically */
      if (strncmp(l, p->pri->internationalprefix, strlen(p->pri->internationalprefix)) == 0) {
         if (prilocaldialplan == -2) {
            ldp_strip = strlen(p->pri->internationalprefix);
         }
         prilocaldialplan = PRI_INTERNATIONAL_ISDN;
      } else if (strncmp(l, p->pri->nationalprefix, strlen(p->pri->nationalprefix)) == 0) {
         if (prilocaldialplan == -2) {
            ldp_strip = strlen(p->pri->nationalprefix);
         }
         prilocaldialplan = PRI_NATIONAL_ISDN;
      } else {
         prilocaldialplan = PRI_LOCAL_ISDN;
      }
   } else if (prilocaldialplan == -1) {
      /* Use the numbering plan passed in. */
      prilocaldialplan = connected_id.number.plan;
   }
   if (l != NULL) {
      while (*l > '9' && *l != '*' && *l != '#') {
         switch (*l) {
         case 'U':
            prilocaldialplan = (PRI_TON_UNKNOWN << 4) | (prilocaldialplan & 0xf);
            break;
         case 'I':
            prilocaldialplan = (PRI_TON_INTERNATIONAL << 4) | (prilocaldialplan & 0xf);
            break;
         case 'N':
            prilocaldialplan = (PRI_TON_NATIONAL << 4) | (prilocaldialplan & 0xf);
            break;
         case 'L':
            prilocaldialplan = (PRI_TON_NET_SPECIFIC << 4) | (prilocaldialplan & 0xf);
            break;
         case 'S':
            prilocaldialplan = (PRI_TON_SUBSCRIBER << 4) | (prilocaldialplan & 0xf);
            break;
         case 'V':
            prilocaldialplan = (PRI_TON_ABBREVIATED << 4) | (prilocaldialplan & 0xf);
            break;
         case 'R':
            prilocaldialplan = (PRI_TON_RESERVED << 4) | (prilocaldialplan & 0xf);
            break;
         case 'u':
            prilocaldialplan = PRI_NPI_UNKNOWN | (prilocaldialplan & 0xf0);
            break;
         case 'e':
            prilocaldialplan = PRI_NPI_E163_E164 | (prilocaldialplan & 0xf0);
            break;
         case 'x':
            prilocaldialplan = PRI_NPI_X121 | (prilocaldialplan & 0xf0);
            break;
         case 'f':
            prilocaldialplan = PRI_NPI_F69 | (prilocaldialplan & 0xf0);
            break;
         case 'n':
            prilocaldialplan = PRI_NPI_NATIONAL | (prilocaldialplan & 0xf0);
            break;
         case 'p':
            prilocaldialplan = PRI_NPI_PRIVATE | (prilocaldialplan & 0xf0);
            break;
         case 'r':
            prilocaldialplan = PRI_NPI_RESERVED | (prilocaldialplan & 0xf0);
            break;
         default:
            if (isalpha(*l)) {
               ast_log(LOG_WARNING,
                  "Unrecognized prilocaldialplan %s modifier: %c\n",
                  *l > 'Z' ? "NPI" : "TON", *l);
            }
            break;
         }
         l++;
      }
   }
   pri_sr_set_caller(sr, l ? (l + ldp_strip) : NULL, n, prilocaldialplan,
      p->use_callingpres ? connected_id.number.presentation : (l ? PRES_ALLOWED_USER_NUMBER_PASSED_SCREEN : PRES_NUMBER_NOT_AVAILABLE));

#if defined(HAVE_PRI_SUBADDR)
   if (connected_id.subaddress.valid) {
      struct pri_party_subaddress subaddress;

      memset(&subaddress, 0, sizeof(subaddress));
      sig_pri_party_subaddress_from_ast(&subaddress, &connected_id.subaddress);
      pri_sr_set_caller_subaddress(sr, &subaddress);
   }
#endif   /* defined(HAVE_PRI_SUBADDR) */

   sig_pri_redirecting_update(p, ast);

#ifdef SUPPORT_USERUSER
   /* User-user info */
   useruser = pbx_builtin_getvar_helper(p->owner, "USERUSERINFO");
   if (useruser)
      pri_sr_set_useruser(sr, useruser);
#endif

#if defined(HAVE_PRI_CCSS)
   if (ast_cc_is_recall(ast, &core_id, sig_pri_cc_type_name)) {
      struct ast_cc_monitor *monitor;
      char device_name[AST_CHANNEL_NAME];

      /* This is a CC recall call. */
      ast_channel_get_device_name(ast, device_name, sizeof(device_name));
      monitor = ast_cc_get_monitor_by_recall_core_id(core_id, device_name);
      if (monitor) {
         struct sig_pri_cc_monitor_instance *instance;

         instance = monitor->private_data;

         /* If this fails then we have monitor instance ambiguity. */
         ast_assert(p->pri == instance->pri);

         if (pri_cc_call(p->pri->pri, instance->cc_id, p->call, sr)) {
            /* The CC recall call failed for some reason. */
            ast_log(LOG_WARNING, "Unable to setup CC recall call to device %s\n",
               device_name);
            ao2_ref(monitor, -1);
            pri_destroycall(p->pri->pri, p->call);
            p->call = NULL;
            pri_rel(p->pri);
            pri_sr_free(sr);
            return -1;
         }
         ao2_ref(monitor, -1);
      } else {
         core_id = -1;
      }
   } else
#endif   /* defined(HAVE_PRI_CCSS) */
   {
      core_id = -1;
   }
   if (core_id == -1 && pri_setup(p->pri->pri, p->call, sr)) {
      ast_log(LOG_WARNING, "Unable to setup call to %s (using %s)\n",
         c + p->stripmsd + dp_strip, dialplan2str(p->pri->dialplan));
      pri_destroycall(p->pri->pri, p->call);
      p->call = NULL;
      pri_rel(p->pri);
      pri_sr_free(sr);
      return -1;
   }
   p->call_level = SIG_PRI_CALL_LEVEL_SETUP;
   pri_sr_free(sr);
   ast_setstate(ast, AST_STATE_DIALING);
   sig_pri_set_dialing(p, 1);
   pri_rel(p->pri);
   return 0;
}

int sig_pri_indicate(struct sig_pri_chan *p, struct ast_channel *chan, int condition, const void *data, size_t datalen)
{
   int res = -1;

   switch (condition) {
   case AST_CONTROL_BUSY:
      if (p->priindication_oob || p->no_b_channel) {
         ast_channel_hangupcause_set(chan, AST_CAUSE_USER_BUSY);
         ast_channel_softhangup_internal_flag_add(chan, AST_SOFTHANGUP_DEV);
         res = 0;
         break;
      }
      res = sig_pri_play_tone(p, SIG_PRI_TONE_BUSY);
      if (p->call_level < SIG_PRI_CALL_LEVEL_ALERTING && !p->outgoing) {
         ast_channel_hangupcause_set(chan, AST_CAUSE_USER_BUSY);
         p->progress = 1;/* No need to send plain PROGRESS after this. */
         if (p->pri && p->pri->pri) {
            pri_grab(p, p->pri);
#ifdef HAVE_PRI_PROG_W_CAUSE
            pri_progress_with_cause(p->pri->pri, p->call, PVT_TO_CHANNEL(p), 1, ast_channel_hangupcause(chan));
#else
            pri_progress(p->pri->pri,p->call, PVT_TO_CHANNEL(p), 1);
#endif
            pri_rel(p->pri);
         }
      }
      break;
   case AST_CONTROL_RINGING:
      if (p->call_level < SIG_PRI_CALL_LEVEL_ALERTING && !p->outgoing) {
         p->call_level = SIG_PRI_CALL_LEVEL_ALERTING;
         if (p->pri && p->pri->pri) {
            pri_grab(p, p->pri);
            pri_acknowledge(p->pri->pri,p->call, PVT_TO_CHANNEL(p),
               p->no_b_channel || p->digital ? 0 : 1);
            pri_rel(p->pri);
         }
      }
      res = sig_pri_play_tone(p, SIG_PRI_TONE_RINGTONE);
      if (ast_channel_state(chan) != AST_STATE_UP) {
         if (ast_channel_state(chan) != AST_STATE_RING)
            ast_setstate(chan, AST_STATE_RINGING);
      }
      break;
   case AST_CONTROL_PROCEEDING:
      ast_debug(1, "Received AST_CONTROL_PROCEEDING on %s\n",ast_channel_name(chan));
      if (p->call_level < SIG_PRI_CALL_LEVEL_PROCEEDING && !p->outgoing) {
         p->call_level = SIG_PRI_CALL_LEVEL_PROCEEDING;
         if (p->pri && p->pri->pri) {
            pri_grab(p, p->pri);
            pri_proceeding(p->pri->pri,p->call, PVT_TO_CHANNEL(p),
               p->no_b_channel || p->digital ? 0 : 1);
            if (!p->no_b_channel && !p->digital) {
               sig_pri_set_dialing(p, 0);
            }
            pri_rel(p->pri);
         }
      }
      /* don't continue in ast_indicate */
      res = 0;
      break;
   case AST_CONTROL_PROGRESS:
      ast_debug(1, "Received AST_CONTROL_PROGRESS on %s\n",ast_channel_name(chan));
      sig_pri_set_digital(p, 0); /* Digital-only calls isn't allowing any inband progress messages */
      if (!p->progress && p->call_level < SIG_PRI_CALL_LEVEL_ALERTING && !p->outgoing
         && !p->no_b_channel) {
         p->progress = 1;/* No need to send plain PROGRESS again. */
         if (p->pri && p->pri->pri) {
            pri_grab(p, p->pri);
#ifdef HAVE_PRI_PROG_W_CAUSE
            pri_progress_with_cause(p->pri->pri,p->call, PVT_TO_CHANNEL(p), 1, -1);  /* no cause at all */
#else
            pri_progress(p->pri->pri,p->call, PVT_TO_CHANNEL(p), 1);
#endif
            pri_rel(p->pri);
         }
      }
      /* don't continue in ast_indicate */
      res = 0;
      break;
   case AST_CONTROL_INCOMPLETE:
      /* If we are connected or if we support overlap dialing, wait for additional digits */
      if (p->call_level == SIG_PRI_CALL_LEVEL_CONNECT || (p->pri->overlapdial & DAHDI_OVERLAPDIAL_INCOMING)) {
         res = 0;
         break;
      }
      /* Otherwise, treat as congestion */
      ast_channel_hangupcause_set(chan, AST_CAUSE_INVALID_NUMBER_FORMAT);
      /* Falls through */
   case AST_CONTROL_CONGESTION:
      if (p->priindication_oob || p->no_b_channel) {
         /* There are many cause codes that generate an AST_CONTROL_CONGESTION. */
         switch (ast_channel_hangupcause(chan)) {
         case AST_CAUSE_USER_BUSY:
         case AST_CAUSE_NORMAL_CLEARING:
         case 0:/* Cause has not been set. */
            /* Supply a more appropriate cause. */
            ast_channel_hangupcause_set(chan, AST_CAUSE_SWITCH_CONGESTION);
            break;
         default:
            break;
         }
         ast_channel_softhangup_internal_flag_add(chan, AST_SOFTHANGUP_DEV);
         res = 0;
         break;
      }
      res = sig_pri_play_tone(p, SIG_PRI_TONE_CONGESTION);
      if (p->call_level < SIG_PRI_CALL_LEVEL_ALERTING && !p->outgoing) {
         /* There are many cause codes that generate an AST_CONTROL_CONGESTION. */
         switch (ast_channel_hangupcause(chan)) {
         case AST_CAUSE_USER_BUSY:
         case AST_CAUSE_NORMAL_CLEARING:
         case 0:/* Cause has not been set. */
            /* Supply a more appropriate cause. */
            ast_channel_hangupcause_set(chan, AST_CAUSE_SWITCH_CONGESTION);
            break;
         default:
            break;
         }
         p->progress = 1;/* No need to send plain PROGRESS after this. */
         if (p->pri && p->pri->pri) {
            pri_grab(p, p->pri);
#ifdef HAVE_PRI_PROG_W_CAUSE
            pri_progress_with_cause(p->pri->pri, p->call, PVT_TO_CHANNEL(p), 1, ast_channel_hangupcause(chan));
#else
            pri_progress(p->pri->pri,p->call, PVT_TO_CHANNEL(p), 1);
#endif
            pri_rel(p->pri);
         }
      }
      break;
   case AST_CONTROL_HOLD:
      ast_copy_string(p->moh_suggested, S_OR(data, ""), sizeof(p->moh_suggested));
      if (p->pri) {
         pri_grab(p, p->pri);
         sig_pri_moh_fsm_event(chan, p, SIG_PRI_MOH_EVENT_HOLD);
         pri_rel(p->pri);
      } else {
         /* Something is wrong here.  A PRI channel without the pri pointer? */
         ast_moh_start(chan, data, p->mohinterpret);
      }
      break;
   case AST_CONTROL_UNHOLD:
      if (p->pri) {
         pri_grab(p, p->pri);
         sig_pri_moh_fsm_event(chan, p, SIG_PRI_MOH_EVENT_UNHOLD);
         pri_rel(p->pri);
      } else {
         /* Something is wrong here.  A PRI channel without the pri pointer? */
         ast_moh_stop(chan);
      }
      break;
   case AST_CONTROL_SRCUPDATE:
      res = 0;
      break;
   case -1:
      res = sig_pri_play_tone(p, -1);
      break;
   case AST_CONTROL_CONNECTED_LINE:
      ast_debug(1, "Received AST_CONTROL_CONNECTED_LINE on %s\n", ast_channel_name(chan));
      if (p->pri) {
         struct pri_party_connected_line connected;
         int dialplan;
         int prefix_strip;
         int colp_allowed = 0;
         struct ast_party_id connected_id = ast_channel_connected_effective_id(chan);

         pri_grab(p, p->pri);

         /* Check if a connected line update is allowed at this time. */
         switch (p->pri->colp_send) {
         case SIG_PRI_COLP_BLOCK:
            break;
         case SIG_PRI_COLP_CONNECT:
            /*
             * Outgoing calls receive CONNECT and act like an update before
             * the call is connected.
             */
            if (p->call_level <= SIG_PRI_CALL_LEVEL_ALERTING && !p->outgoing) {
               colp_allowed = 1;
            }
            break;
         case SIG_PRI_COLP_UPDATE:
            colp_allowed = 1;
            break;
         }
         if (!colp_allowed) {
            pri_rel(p->pri);
            ast_debug(1, "Blocked AST_CONTROL_CONNECTED_LINE on %s\n",
               ast_channel_name(chan));
            break;
         }

         memset(&connected, 0, sizeof(connected));
         sig_pri_party_id_from_ast(&connected.id, &connected_id);

         /* Determine the connected line numbering plan to actually use. */
         switch (p->pri->cpndialplan) {
         case -2:/* redundant */
         case -1:/* dynamic */
            /* compute dynamically */
            prefix_strip = 0;
            if (!strncmp(connected.id.number.str, p->pri->internationalprefix,
               strlen(p->pri->internationalprefix))) {
               prefix_strip = strlen(p->pri->internationalprefix);
               dialplan = PRI_INTERNATIONAL_ISDN;
            } else if (!strncmp(connected.id.number.str, p->pri->nationalprefix,
               strlen(p->pri->nationalprefix))) {
               prefix_strip = strlen(p->pri->nationalprefix);
               dialplan = PRI_NATIONAL_ISDN;
            } else {
               dialplan = PRI_LOCAL_ISDN;
            }
            connected.id.number.plan = dialplan;

            if (prefix_strip && p->pri->cpndialplan != -2) {
               /* Strip the prefix from the connected line number. */
               memmove(connected.id.number.str,
                  connected.id.number.str + prefix_strip,
                  strlen(connected.id.number.str + prefix_strip) + 1);
            }
            break;
         case 0:/* from_channel */
            /* Use the numbering plan passed in. */
            break;
         default:
            connected.id.number.plan = p->pri->cpndialplan - 1;
            break;
         }

         pri_connected_line_update(p->pri->pri, p->call, &connected);
         pri_rel(p->pri);
      }
      break;
   case AST_CONTROL_REDIRECTING:
      ast_debug(1, "Received AST_CONTROL_REDIRECTING on %s\n", ast_channel_name(chan));
      if (p->pri) {
         pri_grab(p, p->pri);
         sig_pri_redirecting_update(p, chan);
         pri_rel(p->pri);
      }
      break;
   case AST_CONTROL_AOC:
#if defined(HAVE_PRI_AOC_EVENTS)
      {
         struct ast_aoc_decoded *decoded
            = ast_aoc_decode((struct ast_aoc_encoded *) data, datalen, chan);
         ast_debug(1, "Received AST_CONTROL_AOC on %s\n", ast_channel_name(chan));
         if (decoded && p->pri) {
            pri_grab(p, p->pri);
            switch (ast_aoc_get_msg_type(decoded)) {
            case AST_AOC_S:
               if (p->pri->aoc_passthrough_flag & SIG_PRI_AOC_GRANT_S) {
                  sig_pri_aoc_s_from_ast(p, decoded);
               }
               break;
            case AST_AOC_D:
               if (p->pri->aoc_passthrough_flag & SIG_PRI_AOC_GRANT_D) {
                  sig_pri_aoc_d_from_ast(p, decoded);
               }
               break;
            case AST_AOC_E:
               if (p->pri->aoc_passthrough_flag & SIG_PRI_AOC_GRANT_E) {
                  sig_pri_aoc_e_from_ast(p, decoded);
               }
               /* if hangup was delayed for this AOC-E msg, waiting_for_aoc
                * will be set.  A hangup is already occuring via a timeout during
                * this delay.  Instead of waiting for that timeout to occur, go ahead
                * and initiate the softhangup since the delay is no longer necessary */
               if (p->waiting_for_aoce) {
                  p->waiting_for_aoce = 0;
                  ast_debug(1,
                     "Received final AOC-E msg, continue with hangup on %s\n",
                     ast_channel_name(chan));
                  ast_softhangup_nolock(chan, AST_SOFTHANGUP_DEV);
               }
               break;
            case AST_AOC_REQUEST:
               /* We do not pass through AOC requests, So unless this
                * is an AOC termination request it will be ignored */
               if (ast_aoc_get_termination_request(decoded)) {
                  pri_hangup(p->pri->pri, p->call, -1);
               }
               break;
            default:
               break;
            }
            pri_rel(p->pri);
         }
         ast_aoc_destroy_decoded(decoded);
      }
#endif   /* defined(HAVE_PRI_AOC_EVENTS) */
      break;
#if defined(HAVE_PRI_MCID)
   case AST_CONTROL_MCID:
      if (p->pri && p->pri->pri && p->pri->mcid_send) {
         pri_grab(p, p->pri);
         pri_mcid_req_send(p->pri->pri, p->call);
         pri_rel(p->pri);
      }
      break;
#endif   /* defined(HAVE_PRI_MCID) */
   }

   return res;
}

int sig_pri_answer(struct sig_pri_chan *p, struct ast_channel *ast)
{
   int res;

   /* Send a pri acknowledge */
   pri_grab(p, p->pri);
#if defined(HAVE_PRI_AOC_EVENTS)
   if (p->aoc_s_request_invoke_id_valid) {
      /* if AOC-S was requested and the invoke id is still present on answer.  That means
       * no AOC-S rate list was provided, so send a NULL response which will indicate that
       * AOC-S is not available */
      pri_aoc_s_request_response_send(p->pri->pri, p->call,
         p->aoc_s_request_invoke_id, NULL);
      p->aoc_s_request_invoke_id_valid = 0;
   }
#endif   /* defined(HAVE_PRI_AOC_EVENTS) */
   if (p->call_level < SIG_PRI_CALL_LEVEL_CONNECT) {
      p->call_level = SIG_PRI_CALL_LEVEL_CONNECT;
   }
   sig_pri_set_dialing(p, 0);
   sig_pri_open_media(p);
   res = pri_answer(p->pri->pri, p->call, 0, !p->digital);
   pri_rel(p->pri);
   ast_setstate(ast, AST_STATE_UP);
   return res;
}

/*!
 * \internal
 * \brief Simple check if the channel is available to use.
 * \since 1.8
 *
 * \param pvt Private channel control structure.
 *
 * \retval 0 Interface not available.
 * \retval 1 Interface is available.
 */
static int sig_pri_available_check(struct sig_pri_chan *pvt)
{
   /*
    * If interface has a B channel and is available for use
    * then the channel is available.
    */
   if (!pvt->no_b_channel && sig_pri_is_chan_available(pvt)) {
      return 1;
   }
   return 0;
}

#if defined(HAVE_PRI_CALL_WAITING)
/*!
 * \internal
 * \brief Get an available call waiting interface.
 * \since 1.8
 *
 * \param pri PRI span control structure.
 *
 * \note Assumes the pri->lock is already obtained.
 *
 * \retval cw Call waiting interface to use.
 * \retval NULL if no call waiting interface available.
 */
static struct sig_pri_chan *sig_pri_cw_available(struct sig_pri_span *pri)
{
   struct sig_pri_chan *cw;
   int idx;

   cw = NULL;
   if (pri->num_call_waiting_calls < pri->max_call_waiting_calls) {
      if (!pri->num_call_waiting_calls) {
         /*
          * There are no outstanding call waiting calls.  Check to see
          * if the span is in a congested state for the first call
          * waiting call.
          */
         for (idx = 0; idx < pri->numchans; ++idx) {
            if (pri->pvts[idx] && sig_pri_available_check(pri->pvts[idx])) {
               /* There is another channel that is available on this span. */
               return cw;
            }
         }
      }
      idx = pri_find_empty_nobch(pri);
      if (0 <= idx) {
         /* Setup the call waiting interface to use. */
         cw = pri->pvts[idx];
         cw->is_call_waiting = 1;
         sig_pri_init_config(cw, pri);
         ast_atomic_fetchadd_int(&pri->num_call_waiting_calls, 1);
      }
   }
   return cw;
}
#endif   /* defined(HAVE_PRI_CALL_WAITING) */

int sig_pri_available(struct sig_pri_chan **pvt, int is_specific_channel)
{
   struct sig_pri_chan *p = *pvt;
   struct sig_pri_span *pri;

   if (!p->pri) {
      /* Something is wrong here.  A PRI channel without the pri pointer? */
      return 0;
   }
   pri = p->pri;

   ast_mutex_lock(&pri->lock);
   if (
#if defined(HAVE_PRI_CALL_WAITING)
      /*
       * Only do call waiting calls if we have any
       * call waiting call outstanding.  We do not
       * want new calls to steal a B channel
       * freed for an earlier call waiting call.
       */
      !pri->num_call_waiting_calls &&
#endif   /* defined(HAVE_PRI_CALL_WAITING) */
      sig_pri_available_check(p)) {
      p->allocated = 1;
      ast_mutex_unlock(&pri->lock);
      return 1;
   }

#if defined(HAVE_PRI_CALL_WAITING)
   if (!is_specific_channel) {
      struct sig_pri_chan *cw;

      cw = sig_pri_cw_available(pri);
      if (cw) {
         /* We have a call waiting interface to use instead. */
         cw->allocated = 1;
         *pvt = cw;
         ast_mutex_unlock(&pri->lock);
         return 1;
      }
   }
#endif   /* defined(HAVE_PRI_CALL_WAITING) */
   ast_mutex_unlock(&pri->lock);
   return 0;
}

/* If return 0, it means this function was able to handle it (pre setup digits).  If non zero, the user of this
 * functions should handle it normally (generate inband DTMF) */
int sig_pri_digit_begin(struct sig_pri_chan *pvt, struct ast_channel *ast, char digit)
{
   if (ast_channel_state(ast) == AST_STATE_DIALING) {
      if (pvt->call_level < SIG_PRI_CALL_LEVEL_OVERLAP) {
         unsigned int len;

         len = strlen(pvt->dialdest);
         if (len < sizeof(pvt->dialdest) - 1) {
            ast_debug(1, "Queueing digit '%c' since setup_ack not yet received\n",
               digit);
            pvt->dialdest[len++] = digit;
            pvt->dialdest[len] = '\0';
         } else {
            ast_log(LOG_WARNING,
               "Span %d: Deferred digit buffer overflow for digit '%c'.\n",
               pvt->pri->span, digit);
         }
         return 0;
      }
      if (pvt->call_level < SIG_PRI_CALL_LEVEL_PROCEEDING) {
         pri_grab(pvt, pvt->pri);
         pri_information(pvt->pri->pri, pvt->call, digit);
         pri_rel(pvt->pri);
         return 0;
      }
      if (pvt->call_level < SIG_PRI_CALL_LEVEL_CONNECT) {
         ast_log(LOG_WARNING,
            "Span %d: Digit '%c' may be ignored by peer. (Call level:%d(%s))\n",
            pvt->pri->span, digit, pvt->call_level,
            sig_pri_call_level2str(pvt->call_level));
      }
   }
   return 1;
}

/*!
 * \brief DTMF dial string complete.
 * \since 1.8.11
 *
 * \param pvt sig_pri private channel structure.
 * \param ast Asterisk channel
 *
 * \note Channel and private lock are already held.
 *
 * \return Nothing
 */
void sig_pri_dial_complete(struct sig_pri_chan *pvt, struct ast_channel *ast)
{
   /* If we just completed 'w' deferred dialing digits, we need to answer now. */
   if (pvt->call_level == SIG_PRI_CALL_LEVEL_DEFER_DIAL) {
      pvt->call_level = SIG_PRI_CALL_LEVEL_CONNECT;

      sig_pri_open_media(pvt);
      {
         struct ast_frame f = {AST_FRAME_CONTROL, };

         if (sig_pri_callbacks.queue_control) {
            sig_pri_callbacks.queue_control(pvt->chan_pvt, AST_CONTROL_ANSWER);
         }

         f.subclass.integer = AST_CONTROL_ANSWER;
         ast_queue_frame(ast, &f);
      }
      sig_pri_set_dialing(pvt, 0);
      /* Enable echo cancellation if it's not on already */
      sig_pri_set_echocanceller(pvt, 1);
   }
}

#if defined(HAVE_PRI_MWI)
/*!
 * \internal
 * \brief Send a MWI indication to the given span.
 * \since 1.8
 *
 * \param pri PRI span control structure.
 * \param vm_number Voicemail controlling number (NULL if not present).
 * \param mbox_number Mailbox number
 * \param mbox_context Mailbox context
 * \param num_messages Number of messages waiting.
 *
 * \return Nothing
 */
static void sig_pri_send_mwi_indication(struct sig_pri_span *pri, const char *vm_number, const char *mbox_number, const char *mbox_context, int num_messages)
{
   struct pri_party_id voicemail;
   struct pri_party_id mailbox;

   ast_debug(1, "Send MWI indication for %s@%s vm_number:%s num_messages:%d\n",
      mbox_number, mbox_context, S_OR(vm_number, "<not-present>"), num_messages);

   memset(&mailbox, 0, sizeof(mailbox));
   mailbox.number.valid = 1;
   mailbox.number.presentation = PRES_ALLOWED_USER_NUMBER_NOT_SCREENED;
   mailbox.number.plan = (PRI_TON_UNKNOWN << 4) | PRI_NPI_UNKNOWN;
   ast_copy_string(mailbox.number.str, mbox_number, sizeof(mailbox.number.str));

   memset(&voicemail, 0, sizeof(voicemail));
   voicemail.number.valid = 1;
   voicemail.number.presentation = PRES_ALLOWED_USER_NUMBER_NOT_SCREENED;
   voicemail.number.plan = (PRI_TON_UNKNOWN << 4) | PRI_NPI_UNKNOWN;
   if (vm_number) {
      ast_copy_string(voicemail.number.str, vm_number, sizeof(voicemail.number.str));
   }

   ast_mutex_lock(&pri->lock);
#if defined(HAVE_PRI_MWI_V2)
   pri_mwi_indicate_v2(pri->pri, &mailbox, &voicemail, 1 /* speech */, num_messages,
      NULL, NULL, -1, 0);
#else /* !defined(HAVE_PRI_MWI_V2) */
   pri_mwi_indicate(pri->pri, &mailbox, 1 /* speech */, num_messages, NULL, NULL, -1, 0);
#endif   /* !defined(HAVE_PRI_MWI_V2) */
   ast_mutex_unlock(&pri->lock);
}
#endif   /* defined(HAVE_PRI_MWI) */

#if defined(HAVE_PRI_MWI)
/*!
 * \internal
 * \brief MWI subscription event callback.
 * \since 1.8
 *
 * \param event the event being passed to the subscriber
 * \param userdata the data provider in the call to ast_event_subscribe()
 *
 * \return Nothing
 */
static void sig_pri_mwi_event_cb(const struct ast_event *event, void *userdata)
{
   struct sig_pri_span *pri = userdata;
   const char *mbox_context;
   const char *mbox_number;
   int num_messages;
   int idx;

   mbox_number = ast_event_get_ie_str(event, AST_EVENT_IE_MAILBOX);
   if (ast_strlen_zero(mbox_number)) {
      return;
   }
   mbox_context = ast_event_get_ie_str(event, AST_EVENT_IE_CONTEXT);
   if (ast_strlen_zero(mbox_context)) {
      return;
   }
   num_messages = ast_event_get_ie_uint(event, AST_EVENT_IE_NEWMSGS);

   for (idx = 0; idx < ARRAY_LEN(pri->mbox); ++idx) {
      if (!pri->mbox[idx].sub) {
         /* Mailbox slot is empty */
         continue;
      }
      if (!strcmp(pri->mbox[idx].number, mbox_number)
         && !strcmp(pri->mbox[idx].context, mbox_context)) {
         /* Found the mailbox. */
         sig_pri_send_mwi_indication(pri, pri->mbox[idx].vm_number, mbox_number,
            mbox_context, num_messages);
         break;
      }
   }
}
#endif   /* defined(HAVE_PRI_MWI) */

#if defined(HAVE_PRI_MWI)
/*!
 * \internal
 * \brief Send update MWI indications from the event cache.
 * \since 1.8
 *
 * \param pri PRI span control structure.
 *
 * \return Nothing
 */
static void sig_pri_mwi_cache_update(struct sig_pri_span *pri)
{
   int idx;
   int num_messages;
   struct ast_event *event;

   for (idx = 0; idx < ARRAY_LEN(pri->mbox); ++idx) {
      if (!pri->mbox[idx].sub) {
         /* Mailbox slot is empty */
         continue;
      }

      event = ast_event_get_cached(AST_EVENT_MWI,
         AST_EVENT_IE_MAILBOX, AST_EVENT_IE_PLTYPE_STR, pri->mbox[idx].number,
         AST_EVENT_IE_CONTEXT, AST_EVENT_IE_PLTYPE_STR, pri->mbox[idx].context,
         AST_EVENT_IE_END);
      if (!event) {
         /* No cached event for this mailbox. */
         continue;
      }
      num_messages = ast_event_get_ie_uint(event, AST_EVENT_IE_NEWMSGS);
      sig_pri_send_mwi_indication(pri, pri->mbox[idx].vm_number, pri->mbox[idx].number,
         pri->mbox[idx].context, num_messages);
      ast_event_destroy(event);
   }
}
#endif   /* defined(HAVE_PRI_MWI) */

/*!
 * \brief Stop PRI span.
 * \since 1.8
 *
 * \param pri PRI span control structure.
 *
 * \return Nothing
 */
void sig_pri_stop_pri(struct sig_pri_span *pri)
{
#if defined(HAVE_PRI_MWI)
   int idx;
#endif   /* defined(HAVE_PRI_MWI) */

#if defined(HAVE_PRI_MWI)
   for (idx = 0; idx < ARRAY_LEN(pri->mbox); ++idx) {
      if (pri->mbox[idx].sub) {
         pri->mbox[idx].sub = ast_event_unsubscribe(pri->mbox[idx].sub);
      }
   }
#endif   /* defined(HAVE_PRI_MWI) */
}

/*!
 * \internal
 * \brief qsort comparison function.
 * \since 1.8
 *
 * \param left Ptr to sig_pri_chan ptr to compare.
 * \param right Ptr to sig_pri_chan ptr to compare.
 *
 * \retval <0 if left < right.
 * \retval =0 if left == right.
 * \retval >0 if left > right.
 */
static int sig_pri_cmp_pri_chans(const void *left, const void *right)
{
   const struct sig_pri_chan *pvt_left;
   const struct sig_pri_chan *pvt_right;

   pvt_left = *(struct sig_pri_chan **) left;
   pvt_right = *(struct sig_pri_chan **) right;
   if (!pvt_left) {
      if (!pvt_right) {
         return 0;
      }
      return 1;
   }
   if (!pvt_right) {
      return -1;
   }

   return pvt_left->channel - pvt_right->channel;
}

/*!
 * \internal
 * \brief Sort the PRI B channel private pointer array.
 * \since 1.8
 *
 * \param pri PRI span control structure.
 *
 * \details
 * Since the chan_dahdi.conf file can declare channels in any order, we need to sort
 * the private channel pointer array.
 *
 * \return Nothing
 */
static void sig_pri_sort_pri_chans(struct sig_pri_span *pri)
{
   qsort(&pri->pvts, pri->numchans, sizeof(pri->pvts[0]), sig_pri_cmp_pri_chans);
}

int sig_pri_start_pri(struct sig_pri_span *pri)
{
   int x;
   int i;
#if defined(HAVE_PRI_MWI)
   char *saveptr;
   char *prev_vm_number;
   struct ast_str *mwi_description = ast_str_alloca(64);
#endif   /* defined(HAVE_PRI_MWI) */

#if defined(HAVE_PRI_MWI)
   /* Prepare the mbox[] for use. */
   for (i = 0; i < ARRAY_LEN(pri->mbox); ++i) {
      if (pri->mbox[i].sub) {
         pri->mbox[i].sub = ast_event_unsubscribe(pri->mbox[i].sub);
      }
   }
#endif   /* defined(HAVE_PRI_MWI) */

   ast_mutex_init(&pri->lock);
   sig_pri_sort_pri_chans(pri);

#if defined(HAVE_PRI_MWI)
   /*
    * Split the mwi_vm_numbers configuration string into the mbox[].vm_number:
    * vm_number{,vm_number}
    */
   prev_vm_number = NULL;
   saveptr = pri->mwi_vm_numbers;
   for (i = 0; i < ARRAY_LEN(pri->mbox); ++i) {
      char *vm_number;

      vm_number = strsep(&saveptr, ",");
      if (vm_number) {
         vm_number = ast_strip(vm_number);
      }
      if (ast_strlen_zero(vm_number)) {
         /* There was no number so reuse the previous number. */
         vm_number = prev_vm_number;
      } else {
         /* We have a new number. */
         prev_vm_number = vm_number;
      }
      pri->mbox[i].vm_number = vm_number;
   }

   /*
    * Split the mwi_mailboxes configuration string into the mbox[]:
    * mailbox_number[@context]{,mailbox_number[@context]}
    */
   saveptr = pri->mwi_mailboxes;
   for (i = 0; i < ARRAY_LEN(pri->mbox); ++i) {
      char *mbox_number;
      char *mbox_context;

      mbox_number = strsep(&saveptr, ",");
      if (!mbox_number) {
         /* No more defined mailboxes. */
         break;
      }
      /* Split the mailbox_number and context */
      mbox_context = strchr(mbox_number, '@');
      if (mbox_context) {
         *mbox_context++ = '\0';
         mbox_context = ast_strip(mbox_context);
      }
      mbox_number = ast_strip(mbox_number);
      if (ast_strlen_zero(mbox_number)) {
         /* There is no mailbox number.  Skip it. */
         continue;
      }
      if (ast_strlen_zero(mbox_context)) {
         /* There was no context so use the default. */
         mbox_context = "default";
      }

      /* Fill the mbox[] element. */
      pri->mbox[i].number = mbox_number;
      pri->mbox[i].context = mbox_context;
      ast_str_set(&mwi_description, -1, "%s span %d[%d] MWI mailbox %s@%s",
         sig_pri_cc_type_name, pri->span, i, mbox_number, mbox_context);
      pri->mbox[i].sub = ast_event_subscribe(AST_EVENT_MWI, sig_pri_mwi_event_cb,
         ast_str_buffer(mwi_description), pri,
         AST_EVENT_IE_MAILBOX, AST_EVENT_IE_PLTYPE_STR, mbox_number,
         AST_EVENT_IE_CONTEXT, AST_EVENT_IE_PLTYPE_STR, mbox_context,
         AST_EVENT_IE_END);
      if (!pri->mbox[i].sub) {
         ast_log(LOG_ERROR, "%s span %d could not subscribe to MWI events for %s@%s.",
            sig_pri_cc_type_name, pri->span, mbox_number, mbox_context);
      }
#if defined(HAVE_PRI_MWI_V2)
      if (ast_strlen_zero(pri->mbox[i].vm_number)) {
         ast_log(LOG_WARNING, "%s span %d MWI voicemail number for %s@%s is empty.\n",
            sig_pri_cc_type_name, pri->span, mbox_number, mbox_context);
      }
#endif   /* defined(HAVE_PRI_MWI_V2) */
   }
#endif   /* defined(HAVE_PRI_MWI) */

   for (i = 0; i < SIG_PRI_NUM_DCHANS; i++) {
      if (pri->fds[i] == -1) {
         break;
      }

      switch (pri->sig) {
      case SIG_BRI:
         pri->dchans[i] = pri_new_bri(pri->fds[i], 1, pri->nodetype, pri->switchtype);
         break;
      case SIG_BRI_PTMP:
         pri->dchans[i] = pri_new_bri(pri->fds[i], 0, pri->nodetype, pri->switchtype);
         break;
      default:
         pri->dchans[i] = pri_new(pri->fds[i], pri->nodetype, pri->switchtype);
#if defined(HAVE_PRI_SERVICE_MESSAGES)
         if (pri->enable_service_message_support) {
            pri_set_service_message_support(pri->dchans[i], 1);
         }
#endif   /* defined(HAVE_PRI_SERVICE_MESSAGES) */
         break;
      }

      pri_set_overlapdial(pri->dchans[i], (pri->overlapdial & DAHDI_OVERLAPDIAL_OUTGOING) ? 1 : 0);
#ifdef HAVE_PRI_PROG_W_CAUSE
      pri_set_chan_mapping_logical(pri->dchans[i], pri->qsigchannelmapping == DAHDI_CHAN_MAPPING_LOGICAL);
#endif
#ifdef HAVE_PRI_INBANDDISCONNECT
      pri_set_inbanddisconnect(pri->dchans[i], pri->inbanddisconnect);
#endif
      /* Enslave to master if appropriate */
      if (i)
         pri_enslave(pri->dchans[0], pri->dchans[i]);
      if (!pri->dchans[i]) {
         if (pri->fds[i] > 0)
            close(pri->fds[i]);
         pri->fds[i] = -1;
         ast_log(LOG_ERROR, "Unable to create PRI structure\n");
         return -1;
      }
      pri_set_debug(pri->dchans[i], SIG_PRI_DEBUG_DEFAULT);
      pri_set_nsf(pri->dchans[i], pri->nsf);
#ifdef PRI_GETSET_TIMERS
      for (x = 0; x < PRI_MAX_TIMERS; x++) {
         if (pri->pritimers[x] != 0)
            pri_set_timer(pri->dchans[i], x, pri->pritimers[x]);
      }
#endif
   }

   /* Assume primary is the one we use */
   pri->pri = pri->dchans[0];

#if defined(HAVE_PRI_CALL_HOLD)
   pri_hold_enable(pri->pri, 1);
#endif   /* defined(HAVE_PRI_CALL_HOLD) */
#if defined(HAVE_PRI_CALL_REROUTING)
   pri_reroute_enable(pri->pri, 1);
#endif   /* defined(HAVE_PRI_CALL_REROUTING) */
#if defined(HAVE_PRI_HANGUP_FIX)
   pri_hangup_fix_enable(pri->pri, 1);
#endif   /* defined(HAVE_PRI_HANGUP_FIX) */
#if defined(HAVE_PRI_CCSS)
   pri_cc_enable(pri->pri, 1);
   pri_cc_recall_mode(pri->pri, pri->cc_ptmp_recall_mode);
   pri_cc_retain_signaling_req(pri->pri, pri->cc_qsig_signaling_link_req);
   pri_cc_retain_signaling_rsp(pri->pri, pri->cc_qsig_signaling_link_rsp);
#endif   /* defined(HAVE_PRI_CCSS) */
#if defined(HAVE_PRI_TRANSFER)
   pri_transfer_enable(pri->pri, 1);
#endif   /* defined(HAVE_PRI_TRANSFER) */
#if defined(HAVE_PRI_AOC_EVENTS)
   pri_aoc_events_enable(pri->pri, 1);
#endif   /* defined(HAVE_PRI_AOC_EVENTS) */
#if defined(HAVE_PRI_CALL_WAITING)
   pri_connect_ack_enable(pri->pri, 1);
#endif   /* defined(HAVE_PRI_CALL_WAITING) */
#if defined(HAVE_PRI_MCID)
   pri_mcid_enable(pri->pri, 1);
#endif   /* defined(HAVE_PRI_MCID) */
#if defined(HAVE_PRI_DISPLAY_TEXT)
   pri_display_options_send(pri->pri, pri->display_flags_send);
   pri_display_options_receive(pri->pri, pri->display_flags_receive);
#endif   /* defined(HAVE_PRI_DISPLAY_TEXT) */
#if defined(HAVE_PRI_DATETIME_SEND)
   pri_date_time_send_option(pri->pri, pri->datetime_send);
#endif   /* defined(HAVE_PRI_DATETIME_SEND) */
#if defined(HAVE_PRI_L2_PERSISTENCE)
   pri_persistent_layer2_option(pri->pri, pri->l2_persistence);
#endif   /* defined(HAVE_PRI_L2_PERSISTENCE) */

   pri->resetpos = -1;
   if (ast_pthread_create_background(&pri->master, NULL, pri_dchannel, pri)) {
      for (i = 0; i < SIG_PRI_NUM_DCHANS; i++) {
         if (!pri->dchans[i])
            break;
         if (pri->fds[i] > 0)
            close(pri->fds[i]);
         pri->fds[i] = -1;
      }
      ast_log(LOG_ERROR, "Unable to spawn D-channel: %s\n", strerror(errno));
      return -1;
   }

#if defined(HAVE_PRI_MWI)
   /*
    * Send the initial MWI indications from the event cache for this span.
    *
    * If we were loaded after app_voicemail the event would already be in
    * the cache.  If we were loaded before app_voicemail the event would not
    * be in the cache yet and app_voicemail will send the event when it
    * gets loaded.
    */
   sig_pri_mwi_cache_update(pri);
#endif   /* defined(HAVE_PRI_MWI) */

   return 0;
}

/*!
 * \brief Notify new alarm status.
 *
 * \param p Channel private pointer.
 * \param noalarm Non-zero if not in alarm mode.
 * 
 * \note Assumes the sig_pri_lock_private(p) is already obtained.
 *
 * \return Nothing
 */
void sig_pri_chan_alarm_notify(struct sig_pri_chan *p, int noalarm)
{
   pri_grab(p, p->pri);
   sig_pri_set_alarm(p, !noalarm);
   if (!noalarm) {
      if (pri_get_timer(p->pri->pri, PRI_TIMER_T309) < 0) {
         /* T309 is not enabled : destroy calls when alarm occurs */
         if (p->call) {
            pri_destroycall(p->pri->pri, p->call);
            p->call = NULL;
         }
         if (p->owner)
            ast_channel_softhangup_internal_flag_add(p->owner, AST_SOFTHANGUP_DEV);
      }
   }
   sig_pri_span_devstate_changed(p->pri);
   pri_rel(p->pri);
}

/*!
 * \brief Determine if layer 1 alarms are ignored.
 *
 * \param p Channel private pointer.
 *
 * \return TRUE if the alarm is ignored.
 */
int sig_pri_is_alarm_ignored(struct sig_pri_span *pri)
{
   return pri->layer1_ignored;
}

struct sig_pri_chan *sig_pri_chan_new(void *pvt_data, struct sig_pri_span *pri, int logicalspan, int channo, int trunkgroup)
{
   struct sig_pri_chan *p;

   p = ast_calloc(1, sizeof(*p));
   if (!p)
      return p;

   p->logicalspan = logicalspan;
   p->prioffset = channo;
   p->mastertrunkgroup = trunkgroup;

   p->chan_pvt = pvt_data;

   p->pri = pri;

   return p;
}

/*!
 * \brief Delete the sig_pri private channel structure.
 * \since 1.8
 *
 * \param doomed sig_pri private channel structure to delete.
 *
 * \return Nothing
 */
void sig_pri_chan_delete(struct sig_pri_chan *doomed)
{
   ast_free(doomed);
}

#define SIG_PRI_SC_HEADER  "%-4s %4s %-4s %-4s %-10s %-4s %s\n"
#define SIG_PRI_SC_LINE     "%4d %4d %-4s %-4s %-10s %-4s %s"
void sig_pri_cli_show_channels_header(int fd)
{
   ast_cli(fd, SIG_PRI_SC_HEADER, "PRI",  "",     "B",    "Chan", "Call",  "PRI",  "Channel");
   ast_cli(fd, SIG_PRI_SC_HEADER, "Span", "Chan", "Chan", "Idle", "Level", "Call", "Name");
}

void sig_pri_cli_show_channels(int fd, struct sig_pri_span *pri)
{
   char line[256];
   int idx;
   struct sig_pri_chan *pvt;

   ast_mutex_lock(&pri->lock);
   for (idx = 0; idx < pri->numchans; ++idx) {
      if (!pri->pvts[idx]) {
         continue;
      }
      pvt = pri->pvts[idx];
      sig_pri_lock_private(pvt);
      sig_pri_lock_owner(pri, idx);
      if (pvt->no_b_channel && sig_pri_is_chan_available(pvt)) {
         /* Don't show held/call-waiting channels if they are not in use. */
         sig_pri_unlock_private(pvt);
         continue;
      }

      snprintf(line, sizeof(line), SIG_PRI_SC_LINE,
         pri->span,
         pvt->channel,
         pvt->no_b_channel ? "No" : "Yes",/* Has media */
         sig_pri_is_chan_available(pvt) ? "Yes" : "No",
         sig_pri_call_level2str(pvt->call_level),
         pvt->call ? "Yes" : "No",
         pvt->owner ? ast_channel_name(pvt->owner) : "");

      if (pvt->owner) {
         ast_channel_unlock(pvt->owner);
      }
      sig_pri_unlock_private(pvt);

      ast_mutex_unlock(&pri->lock);
      ast_cli(fd, "%s\n", line);
      ast_mutex_lock(&pri->lock);
   }
   ast_mutex_unlock(&pri->lock);
}

static void build_status(char *s, size_t len, int status, int active)
{
   if (!s || len < 1) {
      return;
   }
   snprintf(s, len, "%s%s, %s",
      (status & DCHAN_NOTINALARM) ? "" : "In Alarm, ",
      (status & DCHAN_UP) ? "Up" : "Down",
      (active) ? "Active" : "Standby");
}

void sig_pri_cli_show_spans(int fd, int span, struct sig_pri_span *pri)
{
   char status[256];
   int x;
   for (x = 0; x < SIG_PRI_NUM_DCHANS; x++) {
      if (pri->dchans[x]) {
         build_status(status, sizeof(status), pri->dchanavail[x], pri->dchans[x] == pri->pri);
         ast_cli(fd, "PRI span %d/%d: %s\n", span, x, status);
      }
   }
}

void sig_pri_cli_show_span(int fd, int *dchannels, struct sig_pri_span *pri)
{
   int x;
   char status[256];

   for (x = 0; x < SIG_PRI_NUM_DCHANS; x++) {
      if (pri->dchans[x]) {
#ifdef PRI_DUMP_INFO_STR
         char *info_str = NULL;
#endif
         ast_cli(fd, "%s D-channel: %d\n", pri_order(x), dchannels[x]);
         build_status(status, sizeof(status), pri->dchanavail[x], pri->dchans[x] == pri->pri);
         ast_cli(fd, "Status: %s\n", status);
         ast_mutex_lock(&pri->lock);
#ifdef PRI_DUMP_INFO_STR
         info_str = pri_dump_info_str(pri->pri);
         if (info_str) {
            ast_cli(fd, "%s", info_str);
            ast_std_free(info_str);
         }
#else
         pri_dump_info(pri->pri);
#endif
         ast_mutex_unlock(&pri->lock);
         ast_cli(fd, "Overlap Recv: %s\n\n", (pri->overlapdial & DAHDI_OVERLAPDIAL_INCOMING)?"Yes":"No");
         ast_cli(fd, "\n");
      }
   }
}

int pri_send_keypad_facility_exec(struct sig_pri_chan *p, const char *digits)
{
   sig_pri_lock_private(p);

   if (!p->pri || !p->call) {
      ast_debug(1, "Unable to find pri or call on channel!\n");
      sig_pri_unlock_private(p);
      return -1;
   }

   pri_grab(p, p->pri);
   pri_keypad_facility(p->pri->pri, p->call, digits);
   pri_rel(p->pri);

   sig_pri_unlock_private(p);

   return 0;
}

int pri_send_callrerouting_facility_exec(struct sig_pri_chan *p, enum ast_channel_state chanstate, const char *destination, const char *original, const char *reason)
{
   int res;

   sig_pri_lock_private(p);

   if (!p->pri || !p->call) {
      ast_debug(1, "Unable to find pri or call on channel!\n");
      sig_pri_unlock_private(p);
      return -1;
   }

   pri_grab(p, p->pri);
   res = pri_callrerouting_facility(p->pri->pri, p->call, destination, original, reason);
   pri_rel(p->pri);

   sig_pri_unlock_private(p);

   return res;
}

#if defined(HAVE_PRI_SERVICE_MESSAGES)
int pri_maintenance_bservice(struct pri *pri, struct sig_pri_chan *p, int changestatus)
{
   int channel = PVT_TO_CHANNEL(p);
   int span = PRI_SPAN(channel);

   return pri_maintenance_service(pri, span, channel, changestatus);
}
#endif   /* defined(HAVE_PRI_SERVICE_MESSAGES) */

void sig_pri_fixup(struct ast_channel *oldchan, struct ast_channel *newchan, struct sig_pri_chan *pchan)
{
   if (pchan->owner == oldchan) {
      pchan->owner = newchan;
   }
}

#if defined(HAVE_PRI_DISPLAY_TEXT)
/*!
 * \brief Send display text.
 * \since 10.0
 *
 * \param p Channel to send text over
 * \param text Text to send.
 *
 * \return Nothing
 */
void sig_pri_sendtext(struct sig_pri_chan *p, const char *text)
{
   struct pri_subcmd_display_txt display;

   if (p->pri && p->pri->pri) {
      ast_copy_string(display.text, text, sizeof(display.text));
      display.length = strlen(display.text);
      display.char_set = 0;/* unknown(0) */
      pri_grab(p, p->pri);
      pri_display_text(p->pri->pri, p->call, &display);
      pri_rel(p->pri);
   }
}
#endif   /* defined(HAVE_PRI_DISPLAY_TEXT) */

#if defined(HAVE_PRI_CCSS)
/*!
 * \brief PRI CC agent initialization.
 * \since 1.8
 *
 * \param agent CC core agent control.
 * \param pvt_chan Original channel the agent will attempt to recall.
 *
 * \details
 * This callback is called when the CC core is initialized.  Agents should allocate
 * any private data necessary for the call and assign it to the private_data
 * on the agent.  Additionally, if any ast_cc_agent_flags are pertinent to the
 * specific agent type, they should be set in this function as well.
 *
 * \retval 0 on success.
 * \retval -1 on error.
 */
int sig_pri_cc_agent_init(struct ast_cc_agent *agent, struct sig_pri_chan *pvt_chan)
{
   struct sig_pri_cc_agent_prv *cc_pvt;

   cc_pvt = ast_calloc(1, sizeof(*cc_pvt));
   if (!cc_pvt) {
      return -1;
   }

   ast_mutex_lock(&pvt_chan->pri->lock);
   cc_pvt->pri = pvt_chan->pri;
   cc_pvt->cc_id = pri_cc_available(pvt_chan->pri->pri, pvt_chan->call);
   ast_mutex_unlock(&pvt_chan->pri->lock);
   if (cc_pvt->cc_id == -1) {
      ast_free(cc_pvt);
      return -1;
   }
   agent->private_data = cc_pvt;
   return 0;
}
#endif   /* defined(HAVE_PRI_CCSS) */

#if defined(HAVE_PRI_CCSS)
/*!
 * \brief Start the offer timer.
 * \since 1.8
 *
 * \param agent CC core agent control.
 *
 * \details
 * This is called by the core when the caller hangs up after
 * a call for which CC may be requested. The agent should
 * begin the timer as configured.
 *
 * The primary reason why this functionality is left to
 * the specific agent implementations is due to the differing
 * use of schedulers throughout the code. Some channel drivers
 * may already have a scheduler context they wish to use, and
 * amongst those, some may use the ast_sched API while others
 * may use the ast_sched_thread API, which are incompatible.
 *
 * \retval 0 on success.
 * \retval -1 on error.
 */
int sig_pri_cc_agent_start_offer_timer(struct ast_cc_agent *agent)
{
   /* libpri maintains it's own offer timer in the form of T_RETENTION. */
   return 0;
}
#endif   /* defined(HAVE_PRI_CCSS) */

#if defined(HAVE_PRI_CCSS)
/*!
 * \brief Stop the offer timer.
 * \since 1.8
 *
 * \param agent CC core agent control.
 *
 * \details
 * This callback is called by the CC core when the caller
 * has requested CC.
 *
 * \retval 0 on success.
 * \retval -1 on error.
 */
int sig_pri_cc_agent_stop_offer_timer(struct ast_cc_agent *agent)
{
   /* libpri maintains it's own offer timer in the form of T_RETENTION. */
   return 0;
}
#endif   /* defined(HAVE_PRI_CCSS) */

#if defined(HAVE_PRI_CCSS)
/*!
 * \brief Response to a CC request.
 * \since 1.8
 *
 * \param agent CC core agent control.
 * \param reason CC request response status.
 *
 * \details
 * When the core receives knowledge that a called
 * party has accepted a CC request, it will call
 * this callback.  The core may also call this
 * if there is some error when attempting to process
 * the incoming CC request.
 *
 * The duty of this is to issue a propper response to a
 * CC request from the caller by acknowledging receipt
 * of that request or rejecting it.
 *
 * \return Nothing
 */
void sig_pri_cc_agent_req_rsp(struct ast_cc_agent *agent, enum ast_cc_agent_response_reason reason)
{
   struct sig_pri_cc_agent_prv *cc_pvt;
   int res;
   int status;
   const char *failed_msg;
   static const char *failed_to_send = "Failed to send the CC request response.";
   static const char *not_accepted = "The core declined the CC request.";

   cc_pvt = agent->private_data;
   ast_mutex_lock(&cc_pvt->pri->lock);
   if (cc_pvt->cc_request_response_pending) {
      cc_pvt->cc_request_response_pending = 0;

      /* Convert core response reason to ISDN response status. */
      status = 2;/* short_term_denial */
      switch (reason) {
      case AST_CC_AGENT_RESPONSE_SUCCESS:
         status = 0;/* success */
         break;
      case AST_CC_AGENT_RESPONSE_FAILURE_INVALID:
         status = 2;/* short_term_denial */
         break;
      case AST_CC_AGENT_RESPONSE_FAILURE_TOO_MANY:
         status = 5;/* queue_full */
         break;
      }

      res = pri_cc_req_rsp(cc_pvt->pri->pri, cc_pvt->cc_id, status);
      if (!status) {
         /* CC core request was accepted. */
         if (res) {
            failed_msg = failed_to_send;
         } else {
            failed_msg = NULL;
         }
      } else {
         /* CC core request was declined. */
         if (res) {
            failed_msg = failed_to_send;
         } else {
            failed_msg = not_accepted;
         }
      }
   } else {
      failed_msg = NULL;
   }
   ast_mutex_unlock(&cc_pvt->pri->lock);
   if (failed_msg) {
      ast_cc_failed(agent->core_id, "%s agent: %s", sig_pri_cc_type_name, failed_msg);
   }
}
#endif   /* defined(HAVE_PRI_CCSS) */

#if defined(HAVE_PRI_CCSS)
/*!
 * \brief Request the status of the agent's device.
 * \since 1.8
 *
 * \param agent CC core agent control.
 *
 * \details
 * Asynchronous request for the status of any caller
 * which may be a valid caller for the CC transaction.
 * Status responses should be made using the
 * ast_cc_status_response function.
 *
 * \retval 0 on success.
 * \retval -1 on error.
 */
int sig_pri_cc_agent_status_req(struct ast_cc_agent *agent)
{
   struct sig_pri_cc_agent_prv *cc_pvt;

   cc_pvt = agent->private_data;
   ast_mutex_lock(&cc_pvt->pri->lock);
   pri_cc_status_req(cc_pvt->pri->pri, cc_pvt->cc_id);
   ast_mutex_unlock(&cc_pvt->pri->lock);
   return 0;
}
#endif   /* defined(HAVE_PRI_CCSS) */

#if defined(HAVE_PRI_CCSS)
/*!
 * \brief Request for an agent's phone to stop ringing.
 * \since 1.8
 *
 * \param agent CC core agent control.
 *
 * \details
 * The usefulness of this is quite limited. The only specific
 * known case for this is if Asterisk requests CC over an ISDN
 * PTMP link as the TE side. If other phones are in the same
 * recall group as the Asterisk server, and one of those phones
 * picks up the recall notice, then Asterisk will receive a
 * "stop ringing" notification from the NT side of the PTMP
 * link. This indication needs to be passed to the phone
 * on the other side of the Asterisk server which originally
 * placed the call so that it will stop ringing. Since the
 * phone may be of any type, it is necessary to have a callback
 * that the core can know about.
 *
 * \retval 0 on success.
 * \retval -1 on error.
 */
int sig_pri_cc_agent_stop_ringing(struct ast_cc_agent *agent)
{
   struct sig_pri_cc_agent_prv *cc_pvt;

   cc_pvt = agent->private_data;
   ast_mutex_lock(&cc_pvt->pri->lock);
   pri_cc_stop_alerting(cc_pvt->pri->pri, cc_pvt->cc_id);
   ast_mutex_unlock(&cc_pvt->pri->lock);
   return 0;
}
#endif   /* defined(HAVE_PRI_CCSS) */

#if defined(HAVE_PRI_CCSS)
/*!
 * \brief Let the caller know that the callee has become free
 * but that the caller cannot attempt to call back because
 * he is either busy or there is congestion on his line.
 * \since 1.8
 *
 * \param agent CC core agent control.
 *
 * \details
 * This is something that really only affects a scenario where
 * a phone places a call over ISDN PTMP to Asterisk, who then
 * connects over PTMP again to the ISDN network. For most agent
 * types, there is no need to implement this callback at all
 * because they don't really need to actually do anything in
 * this situation. If you're having trouble understanding what
 * the purpose of this callback is, then you can be safe simply
 * not implementing it.
 *
 * \retval 0 on success.
 * \retval -1 on error.
 */
int sig_pri_cc_agent_party_b_free(struct ast_cc_agent *agent)
{
   struct sig_pri_cc_agent_prv *cc_pvt;

   cc_pvt = agent->private_data;
   ast_mutex_lock(&cc_pvt->pri->lock);
   pri_cc_b_free(cc_pvt->pri->pri, cc_pvt->cc_id);
   ast_mutex_unlock(&cc_pvt->pri->lock);
   return 0;
}
#endif   /* defined(HAVE_PRI_CCSS) */

#if defined(HAVE_PRI_CCSS)
/*!
 * \brief Begin monitoring a busy device.
 * \since 1.8
 *
 * \param agent CC core agent control.
 *
 * \details
 * The core will call this callback if the callee becomes
 * available but the caller has reported that he is busy.
 * The agent should begin monitoring the caller's device.
 * When the caller becomes available again, the agent should
 * call ast_cc_agent_caller_available.
 *
 * \retval 0 on success.
 * \retval -1 on error.
 */
int sig_pri_cc_agent_start_monitoring(struct ast_cc_agent *agent)
{
   /* libpri already knows when and how it needs to monitor Party A. */
   return 0;
}
#endif   /* defined(HAVE_PRI_CCSS) */

#if defined(HAVE_PRI_CCSS)
/*!
 * \brief Alert the caller that it is time to try recalling.
 * \since 1.8
 *
 * \param agent CC core agent control.
 *
 * \details
 * The core will call this function when it receives notice
 * that a monitored party has become available.
 *
 * The agent's job is to send a message to the caller to
 * notify it of such a change. If the agent is able to
 * discern that the caller is currently unavailable, then
 * the agent should react by calling the ast_cc_caller_unavailable
 * function.
 *
 * \retval 0 on success.
 * \retval -1 on error.
 */
int sig_pri_cc_agent_callee_available(struct ast_cc_agent *agent)
{
   struct sig_pri_cc_agent_prv *cc_pvt;

   cc_pvt = agent->private_data;
   ast_mutex_lock(&cc_pvt->pri->lock);
   pri_cc_remote_user_free(cc_pvt->pri->pri, cc_pvt->cc_id);
   ast_mutex_unlock(&cc_pvt->pri->lock);
   return 0;
}
#endif   /* defined(HAVE_PRI_CCSS) */

#if defined(HAVE_PRI_CCSS)
/*!
 * \brief Destroy private data on the agent.
 * \since 1.8
 *
 * \param agent CC core agent control.
 *
 * \details
 * The core will call this function upon completion
 * or failure of CC.
 *
 * \note
 * The agent private_data pointer may be NULL if the agent
 * constructor failed.
 *
 * \return Nothing
 */
void sig_pri_cc_agent_destructor(struct ast_cc_agent *agent)
{
   struct sig_pri_cc_agent_prv *cc_pvt;
   int res;

   cc_pvt = agent->private_data;
   if (!cc_pvt) {
      /* The agent constructor probably failed. */
      return;
   }
   ast_mutex_lock(&cc_pvt->pri->lock);
   res = -1;
   if (cc_pvt->cc_request_response_pending) {
      res = pri_cc_req_rsp(cc_pvt->pri->pri, cc_pvt->cc_id, 2/* short_term_denial */);
   }
   if (res) {
      pri_cc_cancel(cc_pvt->pri->pri, cc_pvt->cc_id);
   }
   ast_mutex_unlock(&cc_pvt->pri->lock);
   ast_free(cc_pvt);
}
#endif   /* defined(HAVE_PRI_CCSS) */

#if defined(HAVE_PRI_CCSS)
/*!
 * \internal
 * \brief Return the hash value of the given CC monitor instance object.
 * \since 1.8
 *
 * \param obj pointer to the (user-defined part) of an object.
 * \param flags flags from ao2_callback().  Ignored at the moment.
 *
 * \retval core_id
 */
static int sig_pri_cc_monitor_instance_hash_fn(const void *obj, const int flags)
{
   const struct sig_pri_cc_monitor_instance *monitor_instance = obj;

   return monitor_instance->core_id;
}
#endif   /* defined(HAVE_PRI_CCSS) */

#if defined(HAVE_PRI_CCSS)
/*!
 * \internal
 * \brief Compere the monitor instance core_id key value.
 * \since 1.8
 *
 * \param obj pointer to the (user-defined part) of an object.
 * \param arg callback argument from ao2_callback()
 * \param flags flags from ao2_callback()
 *
 * \return values are a combination of enum _cb_results.
 */
static int sig_pri_cc_monitor_instance_cmp_fn(void *obj, void *arg, int flags)
{
   struct sig_pri_cc_monitor_instance *monitor_1 = obj;
   struct sig_pri_cc_monitor_instance *monitor_2 = arg;

   return monitor_1->core_id == monitor_2->core_id ? CMP_MATCH | CMP_STOP : 0;
}
#endif   /* defined(HAVE_PRI_CCSS) */

#if defined(HAVE_PRI_CCSS)
/*!
 * \brief Request CCSS.
 * \since 1.8
 *
 * \param monitor CC core monitor control.
 * \param available_timer_id Where to put the available timer scheduler id.
 * Will never be NULL for a device monitor.
 *
 * \details
 * Perform whatever steps are necessary in order to request CC.
 * In addition, the monitor implementation is responsible for
 * starting the available timer in this callback. The scheduler
 * ID for the callback must be stored in the parent_link's child_avail_id
 * field.
 *
 * \retval 0 on success
 * \retval -1 on failure.
 */
int sig_pri_cc_monitor_req_cc(struct ast_cc_monitor *monitor, int *available_timer_id)
{
   struct sig_pri_cc_monitor_instance *instance;
   int cc_mode;
   int res;

   switch (monitor->service_offered) {
   case AST_CC_CCBS:
      cc_mode = 0;/* CCBS */
      break;
   case AST_CC_CCNR:
      cc_mode = 1;/* CCNR */
      break;
   default:
      /* CC service not supported by ISDN. */
      return -1;
   }

   instance = monitor->private_data;

   /* libpri handles it's own available timer. */
   ast_mutex_lock(&instance->pri->lock);
   res = pri_cc_req(instance->pri->pri, instance->cc_id, cc_mode);
   ast_mutex_unlock(&instance->pri->lock);

   return res;
}
#endif   /* defined(HAVE_PRI_CCSS) */

#if defined(HAVE_PRI_CCSS)
/*!
 * \brief Suspend monitoring.
 * \since 1.8
 *
 * \param monitor CC core monitor control.
 *
 * \details
 * Implementers must perform the necessary steps to suspend
 * monitoring.
 *
 * \retval 0 on success
 * \retval -1 on failure.
 */
int sig_pri_cc_monitor_suspend(struct ast_cc_monitor *monitor)
{
   struct sig_pri_cc_monitor_instance *instance;

   instance = monitor->private_data;
   ast_mutex_lock(&instance->pri->lock);
   pri_cc_status(instance->pri->pri, instance->cc_id, 1/* busy */);
   ast_mutex_unlock(&instance->pri->lock);

   return 0;
}
#endif   /* defined(HAVE_PRI_CCSS) */

#if defined(HAVE_PRI_CCSS)
/*!
 * \brief Unsuspend monitoring.
 * \since 1.8
 *
 * \param monitor CC core monitor control.
 *
 * \details
 * Perform the necessary steps to unsuspend monitoring.
 *
 * \retval 0 on success
 * \retval -1 on failure.
 */
int sig_pri_cc_monitor_unsuspend(struct ast_cc_monitor *monitor)
{
   struct sig_pri_cc_monitor_instance *instance;

   instance = monitor->private_data;
   ast_mutex_lock(&instance->pri->lock);
   pri_cc_status(instance->pri->pri, instance->cc_id, 0/* free */);
   ast_mutex_unlock(&instance->pri->lock);

   return 0;
}
#endif   /* defined(HAVE_PRI_CCSS) */

#if defined(HAVE_PRI_CCSS)
/*!
 * \brief Status response to an ast_cc_monitor_status_request().
 * \since 1.8
 *
 * \param monitor CC core monitor control.
 * \param devstate Current status of a Party A device.
 *
 * \details
 * Alert a monitor as to the status of the agent for which
 * the monitor had previously requested a status request.
 *
 * \note Zero or more responses may come as a result.
 *
 * \retval 0 on success
 * \retval -1 on failure.
 */
int sig_pri_cc_monitor_status_rsp(struct ast_cc_monitor *monitor, enum ast_device_state devstate)
{
   struct sig_pri_cc_monitor_instance *instance;
   int cc_status;

   switch (devstate) {
   case AST_DEVICE_UNKNOWN:
   case AST_DEVICE_NOT_INUSE:
      cc_status = 0;/* free */
      break;
   case AST_DEVICE_BUSY:
   case AST_DEVICE_INUSE:
      cc_status = 1;/* busy */
      break;
   default:
      /* Don't know how to interpret this device state into free/busy status. */
      return 0;
   }
   instance = monitor->private_data;
   ast_mutex_lock(&instance->pri->lock);
   pri_cc_status_req_rsp(instance->pri->pri, instance->cc_id, cc_status);
   ast_mutex_unlock(&instance->pri->lock);

   return 0;
}
#endif   /* defined(HAVE_PRI_CCSS) */

#if defined(HAVE_PRI_CCSS)
/*!
 * \brief Cancel the running available timer.
 * \since 1.8
 *
 * \param monitor CC core monitor control.
 * \param sched_id Available timer scheduler id to cancel.
 * Will never be NULL for a device monitor.
 *
 * \details
 * In most cases, this function will likely consist of just a
 * call to AST_SCHED_DEL. It might have been possible to do this
 * within the core, but unfortunately the mixture of sched_thread
 * and sched usage in Asterisk prevents such usage.
 *
 * \retval 0 on success
 * \retval -1 on failure.
 */
int sig_pri_cc_monitor_cancel_available_timer(struct ast_cc_monitor *monitor, int *sched_id)
{
   /*
    * libpri maintains it's own available timer as one of:
    * T_CCBS2/T_CCBS5/T_CCBS6/QSIG_CCBS_T2
    * T_CCNR2/T_CCNR5/T_CCNR6/QSIG_CCNR_T2
    */
   return 0;
}
#endif   /* defined(HAVE_PRI_CCSS) */

#if defined(HAVE_PRI_CCSS)
/*!
 * \brief Destroy PRI private data on the monitor.
 * \since 1.8
 *
 * \param monitor_pvt CC device monitor private data pointer.
 *
 * \details
 * Implementers of this callback are responsible for destroying
 * all heap-allocated data in the monitor's private_data pointer, including
 * the private_data itself.
 */
void sig_pri_cc_monitor_destructor(void *monitor_pvt)
{
   struct sig_pri_cc_monitor_instance *instance;

   instance = monitor_pvt;
   if (!instance) {
      return;
   }
   ao2_unlink(sig_pri_cc_monitors, instance);
   ao2_ref(instance, -1);
}
#endif   /* defined(HAVE_PRI_CCSS) */

/*!
 * \brief Load the sig_pri submodule.
 * \since 1.8
 *
 * \param cc_type_name CC type name to use when looking up agent/monitor.
 *
 * \retval 0 on success.
 * \retval -1 on error.
 */
int sig_pri_load(const char *cc_type_name)
{
#if defined(HAVE_PRI_CCSS)
   sig_pri_cc_type_name = cc_type_name;
   sig_pri_cc_monitors = ao2_container_alloc(37, sig_pri_cc_monitor_instance_hash_fn,
      sig_pri_cc_monitor_instance_cmp_fn);
   if (!sig_pri_cc_monitors) {
      return -1;
   }
#endif   /* defined(HAVE_PRI_CCSS) */
   return 0;
}

/*!
 * \brief Unload the sig_pri submodule.
 * \since 1.8
 *
 * \return Nothing
 */
void sig_pri_unload(void)
{
#if defined(HAVE_PRI_CCSS)
   if (sig_pri_cc_monitors) {
      ao2_ref(sig_pri_cc_monitors, -1);
      sig_pri_cc_monitors = NULL;
   }
#endif   /* defined(HAVE_PRI_CCSS) */
}

#endif /* HAVE_PRI */