app_nbscat.c

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/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 1999 - 2005, 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 Silly application to play an NBScat file -- uses nbscat8k
 *
 * \author Mark Spencer <markster@digium.com>
 *  
 * \ingroup applications
 */

/*** MODULEINFO
   <support_level>extended</support_level>
 ***/
 
#include "asterisk.h"

ASTERISK_FILE_VERSION(__FILE__, "$Revision: 356573 $")

#include <fcntl.h>
#include <sys/time.h>
#include <sys/socket.h>
#include <signal.h>

#include "asterisk/lock.h"
#include "asterisk/file.h"
#include "asterisk/channel.h"
#include "asterisk/frame.h"
#include "asterisk/pbx.h"
#include "asterisk/module.h"
#include "asterisk/translate.h"
#include "asterisk/app.h"

/*** DOCUMENTATION
   <application name="NBScat" language="en_US">
      <synopsis>
         Play an NBS local stream.
      </synopsis>
      <syntax />
      <description>
         <para>Executes nbscat to listen to the local NBS stream.
         User can exit by pressing any key.</para>
      </description>
   </application>
 ***/

#define LOCAL_NBSCAT "/usr/local/bin/nbscat8k"
#define NBSCAT "/usr/bin/nbscat8k"

#ifndef AF_LOCAL
#define AF_LOCAL AF_UNIX
#endif

static char *app = "NBScat";

static int NBScatplay(int fd)
{
   int res;

   res = ast_safe_fork(0);
   if (res < 0) {
      ast_log(LOG_WARNING, "Fork failed\n");
   }

   if (res) {
      return res;
   }

   if (ast_opt_high_priority)
      ast_set_priority(0);

   dup2(fd, STDOUT_FILENO);
   ast_close_fds_above_n(STDERR_FILENO);
   /* Most commonly installed in /usr/local/bin */
   execl(NBSCAT, "nbscat8k", "-d", (char *)NULL);
   execl(LOCAL_NBSCAT, "nbscat8k", "-d", (char *)NULL);
   fprintf(stderr, "Execute of nbscat8k failed\n");
   _exit(0);
}

static int timed_read(int fd, void *data, int datalen)
{
   int res;
   struct pollfd fds[1];
   fds[0].fd = fd;
   fds[0].events = POLLIN;
   res = ast_poll(fds, 1, 2000);
   if (res < 1) {
      ast_log(LOG_NOTICE, "Selected timed out/errored out with %d\n", res);
      return -1;
   }
   return read(fd, data, datalen);
   
}

static int NBScat_exec(struct ast_channel *chan, const char *data)
{
   int res=0;
   int fds[2];
   int ms = -1;
   int pid = -1;
   struct ast_format owriteformat;
   struct timeval next;
   struct ast_frame *f;
   struct myframe {
      struct ast_frame f;
      char offset[AST_FRIENDLY_OFFSET];
      short frdata[160];
   } myf;

   ast_format_clear(&owriteformat);
   if (socketpair(AF_LOCAL, SOCK_STREAM, 0, fds)) {
      ast_log(LOG_WARNING, "Unable to create socketpair\n");
      return -1;
   }
   
   ast_stopstream(chan);

   ast_format_copy(&owriteformat, ast_channel_writeformat(chan));
   res = ast_set_write_format_by_id(chan, AST_FORMAT_SLINEAR);
   if (res < 0) {
      ast_log(LOG_WARNING, "Unable to set write format to signed linear\n");
      return -1;
   }
   
   res = NBScatplay(fds[1]);
   /* Wait 1000 ms first */
   next = ast_tvnow();
   next.tv_sec += 1;
   if (res >= 0) {
      pid = res;
      /* Order is important -- there's almost always going to be mp3...  we want to prioritize the
         user */
      for (;;) {
         ms = ast_tvdiff_ms(next, ast_tvnow());
         if (ms <= 0) {
            res = timed_read(fds[0], myf.frdata, sizeof(myf.frdata));
            if (res > 0) {
               myf.f.frametype = AST_FRAME_VOICE;
               ast_format_set(&myf.f.subclass.format, AST_FORMAT_SLINEAR, 0);
               myf.f.datalen = res;
               myf.f.samples = res / 2;
               myf.f.mallocd = 0;
               myf.f.offset = AST_FRIENDLY_OFFSET;
               myf.f.src = __PRETTY_FUNCTION__;
               myf.f.delivery.tv_sec = 0;
               myf.f.delivery.tv_usec = 0;
               myf.f.data.ptr = myf.frdata;
               if (ast_write(chan, &myf.f) < 0) {
                  res = -1;
                  break;
               }
            } else {
               ast_debug(1, "No more mp3\n");
               res = 0;
               break;
            }
            next = ast_tvadd(next, ast_samp2tv(myf.f.samples, 8000));
         } else {
            ms = ast_waitfor(chan, ms);
            if (ms < 0) {
               ast_debug(1, "Hangup detected\n");
               res = -1;
               break;
            }
            if (ms) {
               f = ast_read(chan);
               if (!f) {
                  ast_debug(1, "Null frame == hangup() detected\n");
                  res = -1;
                  break;
               }
               if (f->frametype == AST_FRAME_DTMF) {
                  ast_debug(1, "User pressed a key\n");
                  ast_frfree(f);
                  res = 0;
                  break;
               }
               ast_frfree(f);
            } 
         }
      }
   }
   close(fds[0]);
   close(fds[1]);
   
   if (pid > -1)
      kill(pid, SIGKILL);
   if (!res && owriteformat.id)
      ast_set_write_format(chan, &owriteformat);

   return res;
}

static int unload_module(void)
{
   return ast_unregister_application(app);
}

static int load_module(void)
{
   return ast_register_application_xml(app, NBScat_exec);
}

AST_MODULE_INFO_STANDARD(ASTERISK_GPL_KEY, "Silly NBS Stream Application");