res_adsi.c

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/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 1999 - 2005, Digium, Inc.
 *
 * Mark Spencer <markster@digium.com>
 *
 * Includes code and algorithms from the Zapata library.
 *
 * 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 ADSI support
 *
 * \author Mark Spencer <markster@digium.com>
 *
 * \note this module is required by app_voicemail and app_getcpeid
 * \todo Move app_getcpeid into this module
 * \todo Create a core layer so that app_voicemail does not require
 *    res_adsi to load
 */

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

#include "asterisk.h"

ASTERISK_FILE_VERSION(__FILE__, "$Revision: 369326 $")

#include <time.h>
#include <math.h>

#include "asterisk/ulaw.h"
#include "asterisk/alaw.h"
#include "asterisk/callerid.h"
#include "asterisk/fskmodem.h"
#include "asterisk/channel.h"
#include "asterisk/module.h"
#include "asterisk/config.h"
#include "asterisk/file.h"
#include "asterisk/adsi.h"

#define DEFAULT_ADSI_MAX_RETRIES 3

#define ADSI_MAX_INTRO 20
#define ADSI_MAX_SPEED_DIAL 6

#define ADSI_FLAG_DATAMODE (1 << 8)

static int maxretries = DEFAULT_ADSI_MAX_RETRIES;

/* Asterisk ADSI button definitions */
#define ADSI_SPEED_DIAL    10 /* 10-15 are reserved for speed dial */

static char intro[ADSI_MAX_INTRO][20];
static int aligns[ADSI_MAX_INTRO];

#define  SPEEDDIAL_MAX_LEN 20
static char speeddial[ADSI_MAX_SPEED_DIAL][3][SPEEDDIAL_MAX_LEN];

static int alignment = 0;

static int adsi_begin_download(struct ast_channel *chan, char *service, unsigned char *fdn, unsigned char *sec, int version);
static int adsi_end_download(struct ast_channel *chan);
static int adsi_channel_restore(struct ast_channel *chan);
static int adsi_print(struct ast_channel *chan, char **lines, int *align, int voice);
static int adsi_load_session(struct ast_channel *chan, unsigned char *app, int ver, int data);
static int adsi_unload_session(struct ast_channel *chan);
static int adsi_transmit_message(struct ast_channel *chan, unsigned char *msg, int msglen, int msgtype);
static int adsi_transmit_message_full(struct ast_channel *chan, unsigned char *msg, int msglen, int msgtype, int dowait);
static int adsi_read_encoded_dtmf(struct ast_channel *chan, unsigned char *buf, int maxlen);
static int adsi_connect_session(unsigned char *buf, unsigned char *fdn, int ver);
static int adsi_query_cpeid(unsigned char *buf);
static int adsi_query_cpeinfo(unsigned char *buf);
static int adsi_get_cpeid(struct ast_channel *chan, unsigned char *cpeid, int voice);
static int adsi_get_cpeinfo(struct ast_channel *chan, int *width, int *height, int *buttons, int voice);
static int adsi_download_connect(unsigned char *buf, char *service, unsigned char *fdn, unsigned char *sec, int ver);
static int adsi_disconnect_session(unsigned char *buf);
static int adsi_download_disconnect(unsigned char *buf);
static int adsi_data_mode(unsigned char *buf);
static int adsi_clear_soft_keys(unsigned char *buf);
static int adsi_clear_screen(unsigned char *buf);
static int adsi_voice_mode(unsigned char *buf, int when);
static int adsi_available(struct ast_channel *chan);
static int adsi_display(unsigned char *buf, int page, int line, int just, int wrap, char *col1, char *col2);
static int adsi_set_line(unsigned char *buf, int page, int line);
static int adsi_load_soft_key(unsigned char *buf, int key, const char *llabel, const char *slabel, char *ret, int data);
static int adsi_set_keys(unsigned char *buf, unsigned char *keys);
static int adsi_input_control(unsigned char *buf, int page, int line, int display, int format, int just);
static int adsi_input_format(unsigned char *buf, int num, int dir, int wrap, char *format1, char *format2);

static int adsi_generate(unsigned char *buf, int msgtype, unsigned char *msg, int msglen, int msgnum, int last, struct ast_format *codec)
{
   int sum, x, bytes = 0;
   /* Initial carrier (imaginary) */
   float cr = 1.0, ci = 0.0, scont = 0.0;

   if (msglen > 255) {
      msglen = 255;
   }

   /* If first message, Send 150ms of MARK's */
   if (msgnum == 1) {
      for (x = 0; x < 150; x++) { /* was 150 */
         PUT_CLID_MARKMS;
      }
   }

   /* Put message type */
   PUT_CLID(msgtype);
   sum = msgtype;

   /* Put message length (plus one for the message number) */
   PUT_CLID(msglen + 1);
   sum += msglen + 1;

   /* Put message number */
   PUT_CLID(msgnum);
   sum += msgnum;

   /* Put actual message */
   for (x = 0; x < msglen; x++) {
      PUT_CLID(msg[x]);
      sum += msg[x];
   }

   /* Put 2's compliment of sum */
   PUT_CLID(256-(sum & 0xff));

#if 0
   if (last) {
      /* Put trailing marks */
      for (x = 0; x < 50; x++) {
         PUT_CLID_MARKMS;
      }
   }
#endif
   return bytes;

}

static int adsi_careful_send(struct ast_channel *chan, unsigned char *buf, int len, int *remain)
{
   /* Sends carefully on a full duplex channel by using reading for
      timing */
   struct ast_frame *inf, outf;
   int amt;

   /* Zero out our outgoing frame */
   memset(&outf, 0, sizeof(outf));

   if (remain && *remain) {
      amt = len;

      /* Send remainder if provided */
      if (amt > *remain) {
         amt = *remain;
      } else {
         *remain = *remain - amt;
      }
      outf.frametype = AST_FRAME_VOICE;
      ast_format_set(&outf.subclass.format, AST_FORMAT_ULAW, 0);
      outf.data.ptr = buf;
      outf.datalen = amt;
      outf.samples = amt;
      if (ast_write(chan, &outf)) {
         ast_log(LOG_WARNING, "Failed to carefully write frame\n");
         return -1;
      }
      /* Update pointers and lengths */
      buf += amt;
      len -= amt;
   }

   while (len) {
      amt = len;
      /* If we don't get anything at all back in a second, forget
         about it */
      if (ast_waitfor(chan, 1000) < 1) {
         return -1;
      }
      /* Detect hangup */
      if (!(inf = ast_read(chan))) {
         return -1;
      }

      /* Drop any frames that are not voice */
      if (inf->frametype != AST_FRAME_VOICE) {
         ast_frfree(inf);
         continue;
      }

      if (inf->subclass.format.id != AST_FORMAT_ULAW) {
         ast_log(LOG_WARNING, "Channel not in ulaw?\n");
         ast_frfree(inf);
         return -1;
      }
      /* Send no more than they sent us */
      if (amt > inf->datalen) {
         amt = inf->datalen;
      } else if (remain) {
         *remain = inf->datalen - amt;
      }
      outf.frametype = AST_FRAME_VOICE;
      ast_format_set(&outf.subclass.format, AST_FORMAT_ULAW, 0);
      outf.data.ptr = buf;
      outf.datalen = amt;
      outf.samples = amt;
      if (ast_write(chan, &outf)) {
         ast_log(LOG_WARNING, "Failed to carefully write frame\n");
         ast_frfree(inf);
         return -1;
      }
      /* Update pointers and lengths */
      buf += amt;
      len -= amt;
      ast_frfree(inf);
   }
   return 0;
}

static int __adsi_transmit_messages(struct ast_channel *chan, unsigned char **msg, int *msglen, int *msgtype)
{
   /* msglen must be no more than 256 bits, each */
   unsigned char buf[24000 * 5];
   int pos = 0, res, x, start = 0, retries = 0, waittime, rem = 0, def;
   char ack[3];
   struct ast_frame *f;

   if (ast_channel_adsicpe(chan) == AST_ADSI_UNAVAILABLE) {
      /* Don't bother if we know they don't support ADSI */
      errno = ENOSYS;
      return -1;
   }

   while (retries < maxretries) {
      struct ast_format tmpfmt;
      if (!(ast_channel_adsicpe(chan) & ADSI_FLAG_DATAMODE)) {
         /* Generate CAS (no SAS) */
         ast_format_set(&tmpfmt, AST_FORMAT_ULAW, 0);
         ast_gen_cas(buf, 0, 680, &tmpfmt);

         /* Send CAS */
         if (adsi_careful_send(chan, buf, 680, NULL)) {
            ast_log(LOG_WARNING, "Unable to send CAS\n");
         }

         /* Wait For DTMF result */
         waittime = 500;
         for (;;) {
            if (((res = ast_waitfor(chan, waittime)) < 1)) {
               /* Didn't get back DTMF A in time */
               ast_debug(1, "No ADSI CPE detected (%d)\n", res);
               if (!ast_channel_adsicpe(chan)) {
                  ast_channel_adsicpe_set(chan, AST_ADSI_UNAVAILABLE);
               }
               errno = ENOSYS;
               return -1;
            }
            waittime = res;
            if (!(f = ast_read(chan))) {
               ast_debug(1, "Hangup in ADSI\n");
               return -1;
            }
            if (f->frametype == AST_FRAME_DTMF) {
               if (f->subclass.integer == 'A') {
                  /* Okay, this is an ADSI CPE.  Note this for future reference, too */
                  if (!ast_channel_adsicpe(chan)) {
                     ast_channel_adsicpe_set(chan, AST_ADSI_AVAILABLE);
                  }
                  break;
               } else {
                  if (f->subclass.integer == 'D') {
                     ast_debug(1, "Off-hook capable CPE only, not ADSI\n");
                  } else {
                     ast_log(LOG_WARNING, "Unknown ADSI response '%c'\n", f->subclass.integer);
                  }
                  if (!ast_channel_adsicpe(chan)) {
                     ast_channel_adsicpe_set(chan, AST_ADSI_UNAVAILABLE);
                  }
                  errno =  ENOSYS;
                  ast_frfree(f);
                  return -1;
               }
            }
            ast_frfree(f);
         }

         ast_debug(1, "ADSI Compatible CPE Detected\n");
      } else {
         ast_debug(1, "Already in data mode\n");
      }

      x = 0;
      pos = 0;
#if 1
      def= ast_channel_defer_dtmf(chan);
#endif
      while ((x < 6) && msg[x]) {
         if ((res = adsi_generate(buf + pos, msgtype[x], msg[x], msglen[x], x+1 - start, (x == 5) || !msg[x+1], ast_format_set(&tmpfmt, AST_FORMAT_ULAW,0))) < 0) {
            ast_log(LOG_WARNING, "Failed to generate ADSI message %d on channel %s\n", x + 1, ast_channel_name(chan));
            return -1;
         }
         ast_debug(1, "Message %d, of %d input bytes, %d output bytes\n", x + 1, msglen[x], res);
         pos += res;
         x++;
      }


      rem = 0;
      res = adsi_careful_send(chan, buf, pos, &rem);
      if (!def) {
         ast_channel_undefer_dtmf(chan);
      }
      if (res) {
         return -1;
      }

      ast_debug(1, "Sent total spill of %d bytes\n", pos);

      memset(ack, 0, sizeof(ack));
      /* Get real result and check for hangup */
      if ((res = ast_readstring(chan, ack, 2, 1000, 1000, "")) < 0) {
         return -1;
      }
      if (ack[0] == 'D') {
         ast_debug(1, "Acked up to message %d\n", atoi(ack + 1)); start += atoi(ack + 1);
         if (start >= x) {
            break;
         } else {
            retries++;
            ast_debug(1, "Retransmitting (%d), from %d\n", retries, start + 1);
         }
      } else {
         retries++;
         ast_log(LOG_WARNING, "Unexpected response to ack: %s (retry %d)\n", ack, retries);
      }
   }
   if (retries >= maxretries) {
      ast_log(LOG_WARNING, "Maximum ADSI Retries (%d) exceeded\n", maxretries);
      errno = ETIMEDOUT;
      return -1;
   }
   return 0;
}

static int adsi_begin_download(struct ast_channel *chan, char *service, unsigned char *fdn, unsigned char *sec, int version)
{
   int bytes = 0;
   unsigned char buf[256];
   char ack[2];

   /* Setup the resident soft key stuff, a piece at a time */
   /* Upload what scripts we can for voicemail ahead of time */
   bytes += adsi_download_connect(buf + bytes, service, fdn, sec, version);
   if (adsi_transmit_message_full(chan, buf, bytes, ADSI_MSG_DOWNLOAD, 0)) {
      return -1;
   }
   if (ast_readstring(chan, ack, 1, 10000, 10000, "")) {
      return -1;
   }
   if (ack[0] == 'B') {
      return 0;
   }
   ast_debug(1, "Download was denied by CPE\n");
   return -1;
}

static int adsi_end_download(struct ast_channel *chan)
{
   int bytes = 0;
   unsigned char buf[256];

   /* Setup the resident soft key stuff, a piece at a time */
   /* Upload what scripts we can for voicemail ahead of time */
   bytes += adsi_download_disconnect(buf + bytes);
   if (adsi_transmit_message_full(chan, buf, bytes, ADSI_MSG_DOWNLOAD, 0)) {
      return -1;
   }
   return 0;
}

static int adsi_transmit_message_full(struct ast_channel *chan, unsigned char *msg, int msglen, int msgtype, int dowait)
{
   unsigned char *msgs[5] = { NULL, NULL, NULL, NULL, NULL };
   int msglens[5], msgtypes[5], newdatamode = (ast_channel_adsicpe(chan) & ADSI_FLAG_DATAMODE), res, x, waitforswitch = 0;
   struct ast_format writeformat;
   struct ast_format readformat;

   ast_format_copy(&writeformat, ast_channel_writeformat(chan));
   ast_format_copy(&readformat, ast_channel_readformat(chan));

   for (x = 0; x < msglen; x += (msg[x+1]+2)) {
      if (msg[x] == ADSI_SWITCH_TO_DATA) {
         ast_debug(1, "Switch to data is sent!\n");
         waitforswitch++;
         newdatamode = ADSI_FLAG_DATAMODE;
      }

      if (msg[x] == ADSI_SWITCH_TO_VOICE) {
         ast_debug(1, "Switch to voice is sent!\n");
         waitforswitch++;
         newdatamode = 0;
      }
   }
   msgs[0] = msg;

   msglens[0] = msglen;
   msgtypes[0] = msgtype;

   if (msglen > 253) {
      ast_log(LOG_WARNING, "Can't send ADSI message of %d bytes, too large\n", msglen);
      return -1;
   }

   ast_stopstream(chan);

   if (ast_set_write_format_by_id(chan, AST_FORMAT_ULAW)) {
      ast_log(LOG_WARNING, "Unable to set write format to ULAW\n");
      return -1;
   }

   if (ast_set_read_format_by_id(chan, AST_FORMAT_ULAW)) {
      ast_log(LOG_WARNING, "Unable to set read format to ULAW\n");
      if (writeformat.id) {
         if (ast_set_write_format(chan, &writeformat)) {
            ast_log(LOG_WARNING, "Unable to restore write format to %s\n", ast_getformatname(&writeformat));
         }
      }
      return -1;
   }
   res = __adsi_transmit_messages(chan, msgs, msglens, msgtypes);

   if (dowait) {
      ast_debug(1, "Wait for switch is '%d'\n", waitforswitch);
      while (waitforswitch-- && ((res = ast_waitfordigit(chan, 1000)) > 0)) {
         res = 0;
         ast_debug(1, "Waiting for 'B'...\n");
      }
   }

   if (!res) {
      ast_channel_adsicpe_set(chan, (ast_channel_adsicpe(chan) & ~ADSI_FLAG_DATAMODE) | newdatamode);
   }

   if (writeformat.id) {
      ast_set_write_format(chan, &writeformat);
   }
   if (readformat.id) {
      ast_set_read_format(chan, &readformat);
   }

   if (!res) {
      res = ast_safe_sleep(chan, 100 );
   }
   return res;
}

static int adsi_transmit_message(struct ast_channel *chan, unsigned char *msg, int msglen, int msgtype)
{
   return adsi_transmit_message_full(chan, msg, msglen, msgtype, 1);
}

static inline int ccopy(unsigned char *dst, const unsigned char *src, int max)
{
   int x = 0;
   /* Carefully copy the requested data */
   while ((x < max) && src[x] && (src[x] != 0xff)) {
      dst[x] = src[x];
      x++;
   }
   return x;
}

static int adsi_load_soft_key(unsigned char *buf, int key, const char *llabel, const char *slabel, char *ret, int data)
{
   int bytes = 0;

   /* Abort if invalid key specified */
   if ((key < 2) || (key > 33)) {
      return -1;
   }

   buf[bytes++] = ADSI_LOAD_SOFTKEY;
   /* Reserve for length */
   bytes++;
   /* Which key */
   buf[bytes++] = key;

   /* Carefully copy long label */
   bytes += ccopy(buf + bytes, (const unsigned char *)llabel, 18);

   /* Place delimiter */
   buf[bytes++] = 0xff;

   /* Short label */
   bytes += ccopy(buf + bytes, (const unsigned char *)slabel, 7);


   /* If specified, copy return string */
   if (ret) {
      /* Place delimiter */
      buf[bytes++] = 0xff;
      if (data) {
         buf[bytes++] = ADSI_SWITCH_TO_DATA2;
      }
      /* Carefully copy return string */
      bytes += ccopy(buf + bytes, (const unsigned char *)ret, 20);

   }
   /* Replace parameter length */
   buf[1] = bytes - 2;
   return bytes;
}

static int adsi_connect_session(unsigned char *buf, unsigned char *fdn, int ver)
{
   int bytes = 0, x;

   /* Message type */
   buf[bytes++] = ADSI_CONNECT_SESSION;

   /* Reserve space for length */
   bytes++;

   if (fdn) {
      for (x = 0; x < 4; x++) {
         buf[bytes++] = fdn[x];
      }
      if (ver > -1) {
         buf[bytes++] = ver & 0xff;
      }
   }

   buf[1] = bytes - 2;
   return bytes;

}

static int adsi_download_connect(unsigned char *buf, char *service,  unsigned char *fdn, unsigned char *sec, int ver)
{
   int bytes = 0, x;

   /* Message type */
   buf[bytes++] = ADSI_DOWNLOAD_CONNECT;

   /* Reserve space for length */
   bytes++;

   /* Primary column */
   bytes+= ccopy(buf + bytes, (unsigned char *)service, 18);

   /* Delimiter */
   buf[bytes++] = 0xff;

   for (x = 0; x < 4; x++) {
      buf[bytes++] = fdn[x];
   }

   for (x = 0; x < 4; x++) {
      buf[bytes++] = sec[x];
   }

   buf[bytes++] = ver & 0xff;

   buf[1] = bytes - 2;

   return bytes;

}

static int adsi_disconnect_session(unsigned char *buf)
{
   int bytes = 0;

   /* Message type */
   buf[bytes++] = ADSI_DISC_SESSION;

   /* Reserve space for length */
   bytes++;

   buf[1] = bytes - 2;
   return bytes;

}

static int adsi_query_cpeid(unsigned char *buf)
{
   int bytes = 0;
   buf[bytes++] = ADSI_QUERY_CPEID;
   /* Reserve space for length */
   bytes++;
   buf[1] = bytes - 2;
   return bytes;
}

static int adsi_query_cpeinfo(unsigned char *buf)
{
   int bytes = 0;
   buf[bytes++] = ADSI_QUERY_CONFIG;
   /* Reserve space for length */
   bytes++;
   buf[1] = bytes - 2;
   return bytes;
}

static int adsi_read_encoded_dtmf(struct ast_channel *chan, unsigned char *buf, int maxlen)
{
   int bytes = 0, res, gotstar = 0, pos = 0;
   unsigned char current = 0;

   memset(buf, 0, maxlen);

   while (bytes <= maxlen) {
      /* Wait up to a second for a digit */
      if (!(res = ast_waitfordigit(chan, 1000))) {
         break;
      }
      if (res == '*') {
         gotstar = 1;
         continue;
      }
      /* Ignore anything other than a digit */
      if ((res < '0') || (res > '9')) {
         continue;
      }
      res -= '0';
      if (gotstar) {
         res += 9;
      }
      if (pos)  {
         pos = 0;
         buf[bytes++] = (res << 4) | current;
      } else {
         pos = 1;
         current = res;
      }
      gotstar = 0;
   }

   return bytes;
}

static int adsi_get_cpeid(struct ast_channel *chan, unsigned char *cpeid, int voice)
{
   unsigned char buf[256] = "";
   int bytes = 0, res;

   bytes += adsi_data_mode(buf);
   adsi_transmit_message_full(chan, buf, bytes, ADSI_MSG_DISPLAY, 0);

   bytes = 0;
   bytes += adsi_query_cpeid(buf);
   adsi_transmit_message_full(chan, buf, bytes, ADSI_MSG_DISPLAY, 0);

   /* Get response */
   res = adsi_read_encoded_dtmf(chan, cpeid, 4);
   if (res != 4) {
      ast_log(LOG_WARNING, "Got %d bytes back of encoded DTMF, expecting 4\n", res);
      res = 0;
   } else {
      res = 1;
   }

   if (voice) {
      bytes = 0;
      bytes += adsi_voice_mode(buf, 0);
      adsi_transmit_message_full(chan, buf, bytes, ADSI_MSG_DISPLAY, 0);
      /* Ignore the resulting DTMF B announcing it's in voice mode */
      ast_waitfordigit(chan, 1000);
   }
   return res;
}

static int adsi_get_cpeinfo(struct ast_channel *chan, int *width, int *height, int *buttons, int voice)
{
   unsigned char buf[256] = "";
   int bytes = 0, res;

   bytes += adsi_data_mode(buf);
   adsi_transmit_message_full(chan, buf, bytes, ADSI_MSG_DISPLAY, 0);

   bytes = 0;
   bytes += adsi_query_cpeinfo(buf);
   adsi_transmit_message_full(chan, buf, bytes, ADSI_MSG_DISPLAY, 0);

   /* Get width */
   if ((res = ast_readstring(chan, (char *) buf, 2, 1000, 500, "")) < 0) {
      return res;
   }
   if (strlen((char *) buf) != 2) {
      ast_log(LOG_WARNING, "Got %d bytes of width, expecting 2\n", res);
      res = 0;
   } else {
      res = 1;
   }
   if (width) {
      *width = atoi((char *) buf);
   }
   /* Get height */
   memset(buf, 0, sizeof(buf));
   if (res) {
      if ((res = ast_readstring(chan, (char *) buf, 2, 1000, 500, "")) < 0) {
         return res;
      }
      if (strlen((char *) buf) != 2) {
         ast_log(LOG_WARNING, "Got %d bytes of height, expecting 2\n", res);
         res = 0;
      } else {
         res = 1;
      }
      if (height) {
         *height = atoi((char *) buf);
      }
   }
   /* Get buttons */
   memset(buf, 0, sizeof(buf));
   if (res) {
      if ((res = ast_readstring(chan, (char *) buf, 1, 1000, 500, "")) < 0) {
         return res;
      }
      if (strlen((char *) buf) != 1) {
         ast_log(LOG_WARNING, "Got %d bytes of buttons, expecting 1\n", res);
         res = 0;
      } else {
         res = 1;
      }
      if (buttons) {
         *buttons = atoi((char *) buf);
      }
   }
   if (voice) {
      bytes = 0;
      bytes += adsi_voice_mode(buf, 0);
      adsi_transmit_message_full(chan, buf, bytes, ADSI_MSG_DISPLAY, 0);
      /* Ignore the resulting DTMF B announcing it's in voice mode */
      ast_waitfordigit(chan, 1000);
   }
   return res;
}

static int adsi_data_mode(unsigned char *buf)
{
   int bytes = 0;

   /* Message type */
   buf[bytes++] = ADSI_SWITCH_TO_DATA;

   /* Reserve space for length */
   bytes++;

   buf[1] = bytes - 2;
   return bytes;

}

static int adsi_clear_soft_keys(unsigned char *buf)
{
   int bytes = 0;

   /* Message type */
   buf[bytes++] = ADSI_CLEAR_SOFTKEY;

   /* Reserve space for length */
   bytes++;

   buf[1] = bytes - 2;
   return bytes;

}

static int adsi_clear_screen(unsigned char *buf)
{
   int bytes = 0;

   /* Message type */
   buf[bytes++] = ADSI_CLEAR_SCREEN;

   /* Reserve space for length */
   bytes++;

   buf[1] = bytes - 2;
   return bytes;

}

static int adsi_voice_mode(unsigned char *buf, int when)
{
   int bytes = 0;

   /* Message type */
   buf[bytes++] = ADSI_SWITCH_TO_VOICE;

   /* Reserve space for length */
   bytes++;

   buf[bytes++] = when & 0x7f;

   buf[1] = bytes - 2;
   return bytes;

}

static int adsi_available(struct ast_channel *chan)
{
   int cpe = ast_channel_adsicpe(chan) & 0xff;
   if ((cpe == AST_ADSI_AVAILABLE) ||
       (cpe == AST_ADSI_UNKNOWN)) {
      return 1;
   }
   return 0;
}

static int adsi_download_disconnect(unsigned char *buf)
{
   int bytes = 0;

   /* Message type */
   buf[bytes++] = ADSI_DOWNLOAD_DISC;

   /* Reserve space for length */
   bytes++;

   buf[1] = bytes - 2;
   return bytes;

}

static int adsi_display(unsigned char *buf, int page, int line, int just, int wrap,
       char *col1, char *col2)
{
   int bytes = 0;

   /* Sanity check line number */

   if (page) {
      if (line > 4) return -1;
   } else {
      if (line > 33) return -1;
   }

   if (line < 1) {
      return -1;
   }
   /* Parameter type */
   buf[bytes++] = ADSI_LOAD_VIRTUAL_DISP;

   /* Reserve space for size */
   bytes++;

   /* Page and wrap indicator */
   buf[bytes++] = ((page & 0x1) << 7) | ((wrap & 0x1) << 6) | (line & 0x3f);

   /* Justification */
   buf[bytes++] = (just & 0x3) << 5;

   /* Omit highlight mode definition */
   buf[bytes++] = 0xff;

   /* Primary column */
   bytes+= ccopy(buf + bytes, (unsigned char *)col1, 20);

   /* Delimiter */
   buf[bytes++] = 0xff;

   /* Secondary column */
   bytes += ccopy(buf + bytes, (unsigned char *)col2, 20);

   /* Update length */
   buf[1] = bytes - 2;

   return bytes;

}

static int adsi_input_control(unsigned char *buf, int page, int line, int display, int format, int just)
{
   int bytes = 0;

   if (page) {
      if (line > 4) return -1;
   } else {
      if (line > 33) return -1;
   }

   if (line < 1) {
      return -1;
   }

   buf[bytes++] = ADSI_INPUT_CONTROL;
   bytes++;
   buf[bytes++] = ((page & 1) << 7) | (line & 0x3f);
   buf[bytes++] = ((display & 1) << 7) | ((just & 0x3) << 4) | (format & 0x7);

   buf[1] = bytes - 2;
   return bytes;
}

static int adsi_input_format(unsigned char *buf, int num, int dir, int wrap, char *format1, char *format2)
{
   int bytes = 0;

   if (ast_strlen_zero((char *) format1)) {
      return -1;
   }

   buf[bytes++] = ADSI_INPUT_FORMAT;
   bytes++;
   buf[bytes++] = ((dir & 1) << 7) | ((wrap & 1) << 6) | (num & 0x7);
   bytes += ccopy(buf + bytes, (unsigned char *) format1, 20);
   buf[bytes++] = 0xff;
   if (!ast_strlen_zero(format2)) {
      bytes += ccopy(buf + bytes, (unsigned char *) format2, 20);
   }
   buf[1] = bytes - 2;
   return bytes;
}

static int adsi_set_keys(unsigned char *buf, unsigned char *keys)
{
   int bytes = 0, x;

   /* Message type */
   buf[bytes++] = ADSI_INIT_SOFTKEY_LINE;
   /* Space for size */
   bytes++;
   /* Key definitions */
   for (x = 0; x < 6; x++) {
      buf[bytes++] = (keys[x] & 0x3f) ? keys[x] : (keys[x] | 0x1);
   }
   buf[1] = bytes - 2;
   return bytes;
}

static int adsi_set_line(unsigned char *buf, int page, int line)
{
   int bytes = 0;

   /* Sanity check line number */

   if (page) {
      if (line > 4) return -1;
   } else {
      if (line > 33) return -1;
   }

   if (line < 1) {
      return -1;
   }
   /* Parameter type */
   buf[bytes++] = ADSI_LINE_CONTROL;

   /* Reserve space for size */
   bytes++;

   /* Page and line */
   buf[bytes++] = ((page & 0x1) << 7) | (line & 0x3f);

   buf[1] = bytes - 2;
   return bytes;
}

static int total = 0;
static int speeds = 0;

static int adsi_channel_restore(struct ast_channel *chan)
{
   unsigned char dsp[256] = "", keyd[6] = "";
   int bytes, x;

   /* Start with initial display setup */
   bytes = 0;
   bytes += adsi_set_line(dsp + bytes, ADSI_INFO_PAGE, 1);

   /* Prepare key setup messages */

   if (speeds) {
      for (x = 0; x < speeds; x++) {
         keyd[x] = ADSI_SPEED_DIAL + x;
      }
      bytes += adsi_set_keys(dsp + bytes, keyd);
   }
   adsi_transmit_message_full(chan, dsp, bytes, ADSI_MSG_DISPLAY, 0);
   return 0;

}

static int adsi_print(struct ast_channel *chan, char **lines, int *alignments, int voice)
{
   unsigned char buf[4096];
   int bytes = 0, res, x;

   for (x = 0; lines[x]; x++) {
      bytes += adsi_display(buf + bytes, ADSI_INFO_PAGE, x+1, alignments[x], 0, lines[x], "");
   }
   bytes += adsi_set_line(buf + bytes, ADSI_INFO_PAGE, 1);
   if (voice) {
      bytes += adsi_voice_mode(buf + bytes, 0);
   }
   res = adsi_transmit_message_full(chan, buf, bytes, ADSI_MSG_DISPLAY, 0);
   if (voice) {
      /* Ignore the resulting DTMF B announcing it's in voice mode */
      ast_waitfordigit(chan, 1000);
   }
   return res;
}

static int adsi_load_session(struct ast_channel *chan, unsigned char *app, int ver, int data)
{
   unsigned char dsp[256] = "";
   int bytes = 0, res;
   char resp[2];

   /* Connect to session */
   bytes += adsi_connect_session(dsp + bytes, app, ver);

   if (data) {
      bytes += adsi_data_mode(dsp + bytes);
   }

   /* Prepare key setup messages */
   if (adsi_transmit_message_full(chan, dsp, bytes, ADSI_MSG_DISPLAY, 0)) {
      return -1;
   }
   if (app) {
      if ((res = ast_readstring(chan, resp, 1, 1200, 1200, "")) < 0) {
         return -1;
      }
      if (res) {
         ast_debug(1, "No response from CPE about version.  Assuming not there.\n");
         return 0;
      }
      if (!strcmp(resp, "B")) {
         ast_debug(1, "CPE has script '%s' version %d already loaded\n", app, ver);
         return 1;
      } else if (!strcmp(resp, "A")) {
         ast_debug(1, "CPE hasn't script '%s' version %d already loaded\n", app, ver);
      } else {
         ast_log(LOG_WARNING, "Unexpected CPE response to script query: %s\n", resp);
      }
   } else
      return 1;
   return 0;

}

static int adsi_unload_session(struct ast_channel *chan)
{
   unsigned char dsp[256] = "";
   int bytes = 0;

   /* Connect to session */
   bytes += adsi_disconnect_session(dsp + bytes);
   bytes += adsi_voice_mode(dsp + bytes, 0);

   /* Prepare key setup messages */
   if (adsi_transmit_message_full(chan, dsp, bytes, ADSI_MSG_DISPLAY, 0)) {
      return -1;
   }

   return 0;
}

static int str2align(const char *s)
{
   if (!strncasecmp(s, "l", 1)) {
      return ADSI_JUST_LEFT;
   } else if (!strncasecmp(s, "r", 1)) {
      return ADSI_JUST_RIGHT;
   } else if (!strncasecmp(s, "i", 1)) {
      return ADSI_JUST_IND;
   } else {
      return ADSI_JUST_CENT;
   }
}

static void init_state(void)
{
   int x;

   for (x = 0; x < ADSI_MAX_INTRO; x++) {
      aligns[x] = ADSI_JUST_CENT;
   }
   ast_copy_string(intro[0], "Welcome to the", sizeof(intro[0]));
   ast_copy_string(intro[1], "Asterisk", sizeof(intro[1]));
   ast_copy_string(intro[2], "Open Source PBX", sizeof(intro[2]));
   total = 3;
   speeds = 0;
   for (x = 3; x < ADSI_MAX_INTRO; x++) {
      intro[x][0] = '\0';
   }
   memset(speeddial, 0, sizeof(speeddial));
   alignment = ADSI_JUST_CENT;
}

static void adsi_load(int reload)
{
   int x = 0;
   struct ast_config *conf = NULL;
   struct ast_variable *v;
   struct ast_flags config_flags = { reload ? CONFIG_FLAG_FILEUNCHANGED : 0 };
   char *name, *sname;
   init_state();

   conf = ast_config_load("adsi.conf", config_flags);
   if (conf == CONFIG_STATUS_FILEMISSING || conf == CONFIG_STATUS_FILEUNCHANGED || conf == CONFIG_STATUS_FILEINVALID) {
      return;
   }
   for (v = ast_variable_browse(conf, "intro"); v; v = v->next) {
      if (!strcasecmp(v->name, "alignment")) {
         alignment = str2align(v->value);
      } else if (!strcasecmp(v->name, "greeting")) {
         if (x < ADSI_MAX_INTRO) {
            aligns[x] = alignment;
            ast_copy_string(intro[x], v->value, sizeof(intro[x]));
            x++;
         }
      } else if (!strcasecmp(v->name, "maxretries")) {
         if (atoi(v->value) > 0) {
            maxretries = atoi(v->value);
         }
      }
   }
   if (x) {
      total = x;
   }

   x = 0;
   for (v = ast_variable_browse(conf, "speeddial"); v; v = v->next) {
      char buf[3 * SPEEDDIAL_MAX_LEN];
      char *stringp = buf;
      ast_copy_string(buf, v->value, sizeof(buf));
      name = strsep(&stringp, ",");
      sname = strsep(&stringp, ",");
      if (!sname) {
         sname = name;
      }
      if (x < ADSI_MAX_SPEED_DIAL) {
         ast_copy_string(speeddial[x][0], v->name, sizeof(speeddial[x][0]));
         ast_copy_string(speeddial[x][1], name, 18);
         ast_copy_string(speeddial[x][2], sname, 7);
         x++;
      }
   }
   if (x) {
      speeds = x;
   }
   ast_config_destroy(conf);

   return;
}

static int reload(void)
{
   adsi_load(1);
   return 0;
}

static struct adsi_funcs res_adsi_funcs = {
   .version = AST_ADSI_VERSION,
   .begin_download = adsi_begin_download,
   .end_download = adsi_end_download,
   .channel_restore = adsi_channel_restore,
   .print = adsi_print,
   .load_session = adsi_load_session,
   .unload_session = adsi_unload_session,
   .transmit_message = adsi_transmit_message,
   .transmit_message_full = adsi_transmit_message_full,
   .read_encoded_dtmf = adsi_read_encoded_dtmf,
   .connect_session = adsi_connect_session,
   .query_cpeid = adsi_query_cpeid,
   .query_cpeinfo = adsi_query_cpeinfo,
   .get_cpeid = adsi_get_cpeid,
   .get_cpeinfo = adsi_get_cpeinfo,
   .download_connect = adsi_download_connect,
   .disconnect_session = adsi_disconnect_session,
   .download_disconnect = adsi_download_disconnect,
   .data_mode = adsi_data_mode,
   .clear_soft_keys = adsi_clear_soft_keys,
   .clear_screen = adsi_clear_screen,
   .voice_mode = adsi_voice_mode,
   .available = adsi_available,
   .display = adsi_display,
   .set_line = adsi_set_line,
   .load_soft_key = adsi_load_soft_key,
   .set_keys = adsi_set_keys,
   .input_control = adsi_input_control,
   .input_format = adsi_input_format,
};

static int load_module(void)
{
   adsi_load(0);
   ast_adsi_install_funcs(&res_adsi_funcs);
   return AST_MODULE_LOAD_SUCCESS;
}

static int unload_module(void)
{
   /* Can't unload this once we're loaded */
   ast_adsi_install_funcs(NULL);
   return -1;
}

AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_LOAD_ORDER, "ADSI Resource",
      .load = load_module,
      .unload = unload_module,
      .reload = reload,
      .load_pri = AST_MODPRI_APP_DEPEND,
          );