app_waitforsilence.c File Reference

Wait for Silence. More...

#include "asterisk.h"
#include "asterisk/app.h"
#include "asterisk/file.h"
#include "asterisk/channel.h"
#include "asterisk/pbx.h"
#include "asterisk/dsp.h"
#include "asterisk/module.h"
#include "asterisk/format_cache.h"

Include dependency graph for app_waitforsilence.c:

Go to the source code of this file.

Data Structures
struct	wait_type

Functions
	AST_MODULE_INFO_STANDARD_EXTENDED (ASTERISK_GPL_KEY, "Wait For Silence/Noise")
static int	do_waiting (struct ast_channel *chan, int timereqd, time_t waitstart, int timeout, const struct wait_type *wait_for)
static int	load_module (void)
static int	unload_module (void)
static int	waitfor_exec (struct ast_channel *chan, const char *data, const struct wait_type *wait_for)
static int	waitfornoise_exec (struct ast_channel *chan, const char *data)
static int	waitforsilence_exec (struct ast_channel *chan, const char *data)

Variables
static char *	app_noise = "WaitForNoise"
static char *	app_silence = "WaitForSilence"
static const struct wait_type	wait_for_noise
static const struct wait_type	wait_for_silence

Detailed Description

Wait for Silence.

• Waits for up to 'x' milliseconds of silence, 'y' times
  
• WaitForSilence(500,2) will wait for 1/2 second of silence, twice
  
• WaitForSilence(1000,1) will wait for 1 second of silence, once
  
• WaitForSilence(300,3,10) will wait for 300ms of silence, 3 times, and return after 10sec
  

  Author

  David C. Troy dave@.nosp@m.popv.nosp@m.ox.co.nosp@m.m

  Wait For Noise The same as Wait For Silence but listenes noise on the chennel that is above
  the pre-configured silence threshold from dsp.conf

Author

Philipp Skadorov skado.nosp@m.rov@.nosp@m.yahoo.nosp@m..com

Definition in file app_waitforsilence.c.

Function Documentation

AST_MODULE_INFO_STANDARD_EXTENDED()

AST_MODULE_INFO_STANDARD_EXTENDED	(	ASTERISK_GPL_KEY	,
		"Wait For Silence/Noise"
	)

Referenced by load_module().

do_waiting()

static int do_waiting ( struct ast_channel *  chan, int  timereqd, time_t  waitstart, int  timeout, const struct wait_type *  wait_for  )

static

Definition at line 154 of file app_waitforsilence.c.

References ao2_bump, ao2_cleanup, ast_channel_name(), ast_channel_readformat(), ast_debug, ast_dsp_free(), ast_dsp_get_threshold_from_settings(), ast_dsp_new(), ast_dsp_set_threshold(), ast_format_get_name(), ast_format_slin, AST_FRAME_VOICE, ast_frfree, ast_log, ast_read(), ast_set_read_format(), ast_verb, ast_waitfor(), ast_frame::frametype, wait_type::func, LOG_WARNING, wait_type::name, NULL, pbx_builtin_setvar_helper(), RAII_VAR, wait_type::status, wait_type::stop_on_frame_timeout, and THRESHOLD_SILENCE.

Referenced by waitfor_exec().

{
   RAII_VAR(struct ast_format *, rfmt, NULL, ao2_cleanup);
   int res;
   struct ast_dsp *sildet;

   rfmt = ao2_bump(ast_channel_readformat(chan));
   if ((res = ast_set_read_format(chan, ast_format_slin)) < 0) {
      ast_log(LOG_WARNING, "Unable to set channel to linear mode, giving up\n");
      return -1;
   }

   /* Create the silence detector */
   if (!(sildet = ast_dsp_new())) {
      ast_log(LOG_WARNING, "Unable to create silence detector\n");
      return -1;
   }
   ast_dsp_set_threshold(sildet, ast_dsp_get_threshold_from_settings(THRESHOLD_SILENCE));

   for (;;) {
      int dsptime = 0;

      res = ast_waitfor(chan, timereqd);

      /* Must have gotten a hangup; let's exit */
      if (res < 0) {
         pbx_builtin_setvar_helper(chan, "WAITSTATUS", "HANGUP");
         break;
      }

      /* We waited and got no frame; sounds like digital silence or a muted digital channel */
      if (res == 0) {
         if (wait_for->stop_on_frame_timeout) {
            dsptime = timereqd;
         }
      } else {
         /* Looks like we did get a frame, so let's check it out */
         struct ast_frame *f = ast_read(chan);
         if (!f) {
            pbx_builtin_setvar_helper(chan, "WAITSTATUS", "HANGUP");
            break;
         }
         if (f->frametype == AST_FRAME_VOICE) {
            wait_for->func(sildet, f, &dsptime);
         }
         ast_frfree(f);
      }

      ast_debug(1, "Got %dms of %s < %dms required\n", dsptime, wait_for->name, timereqd);

      if (dsptime >= timereqd) {
         ast_verb(3, "Exiting with %dms of %s >= %dms required\n", dsptime, wait_for->name, timereqd);
         pbx_builtin_setvar_helper(chan, "WAITSTATUS", wait_for->status);
         ast_debug(1, "WAITSTATUS was set to %s\n", wait_for->status);
         res = 1;
         break;
      }

      if (timeout && difftime(time(NULL), waitstart) >= timeout) {
         pbx_builtin_setvar_helper(chan, "WAITSTATUS", "TIMEOUT");
         ast_debug(1, "WAITSTATUS was set to TIMEOUT\n");
         res = 0;
         break;
      }
   }

   if (rfmt && ast_set_read_format(chan, rfmt)) {
      ast_log(LOG_WARNING, "Unable to restore format %s to channel '%s'\n", ast_format_get_name(rfmt), ast_channel_name(chan));
   }

   ast_dsp_free(sildet);
   return res;
}

load_module()

static int load_module ( void  )

static

Definition at line 311 of file app_waitforsilence.c.

References app_noise, app_silence, AST_MODULE_INFO_STANDARD_EXTENDED(), ast_register_application_xml, ASTERISK_GPL_KEY, waitfornoise_exec(), and waitforsilence_exec().

{
   int res;

   res = ast_register_application_xml(app_silence, waitforsilence_exec);
   res |= ast_register_application_xml(app_noise, waitfornoise_exec);
   return res;
}

unload_module()

static int unload_module ( void  )

static

Definition at line 302 of file app_waitforsilence.c.

References app_noise, app_silence, and ast_unregister_application().

{
   int res;
   res = ast_unregister_application(app_silence);
   res |= ast_unregister_application(app_noise);

   return res;
}

waitfor_exec()

static int waitfor_exec ( struct ast_channel *  chan, const char *  data, const struct wait_type *  wait_for  )

static

Definition at line 228 of file app_waitforsilence.c.

References args, ast_answer(), AST_APP_ARG, ast_channel_start_silence_generator(), ast_channel_stop_silence_generator(), AST_DECLARE_APP_ARGS, ast_log, ast_opt_transmit_silence, AST_STANDARD_APP_ARGS, AST_STATE_UP, ast_strdupa, ast_strlen_zero, ast_verb, do_waiting(), LOG_ERROR, wait_type::name, NULL, parse(), and timeout.

Referenced by waitfornoise_exec(), and waitforsilence_exec().

{
   int res = 1;
   int timereqd = 1000;
   int timeout = 0;
   int iterations = 1, i;
   time_t waitstart;
   char *parse;
   struct ast_silence_generator *silgen = NULL;

   AST_DECLARE_APP_ARGS(args,
      AST_APP_ARG(timereqd);
      AST_APP_ARG(iterations);
      AST_APP_ARG(timeout);
   );

   parse = ast_strdupa(data);
   AST_STANDARD_APP_ARGS(args, parse);

   if (!ast_strlen_zero(args.timereqd)) {
      if (sscanf(args.timereqd, "%30d", &timereqd) != 1 || timereqd < 0) {
         ast_log(LOG_ERROR, "Argument '%srequired' must be an integer greater than or equal to zero.\n",
               wait_for->name);
         return -1;
      }
   }

   if (!ast_strlen_zero(args.iterations)) {
      if (sscanf(args.iterations, "%30d", &iterations) != 1 || iterations < 1) {
         ast_log(LOG_ERROR, "Argument 'iterations' must be an integer greater than 0.\n");
         return -1;
      }
   }

   if (!ast_strlen_zero(args.timeout)) {
      if (sscanf(args.timeout, "%30d", &timeout) != 1 || timeout < 0) {
         ast_log(LOG_ERROR, "Argument 'timeout' must be an integer greater than or equal to zero.\n");
         return -1;
      }
   }

   if (ast_channel_state(chan) != AST_STATE_UP) {
      ast_answer(chan); /* Answer the channel */
   }

   ast_verb(3, "Waiting %d time(s) for %dms of %s with %ds timeout\n",
          iterations, timereqd, wait_for->name, timeout);

   if (ast_opt_transmit_silence) {
      silgen = ast_channel_start_silence_generator(chan);
   }

   time(&waitstart);
   for (i = 0; i < iterations && res == 1; i++) {
      res = do_waiting(chan, timereqd, waitstart, timeout, wait_for);
   }

   if (silgen) {
      ast_channel_stop_silence_generator(chan, silgen);
   }

   return res > 0 ? 0 : res;
}

waitfornoise_exec()

static int waitfornoise_exec ( struct ast_channel *  chan, const char *  data  )

static

Definition at line 297 of file app_waitforsilence.c.

References waitfor_exec().

Referenced by load_module().

{
   return waitfor_exec(chan, data, &wait_for_noise);
}

waitforsilence_exec()

static int waitforsilence_exec ( struct ast_channel *  chan, const char *  data  )

static

Definition at line 292 of file app_waitforsilence.c.

References waitfor_exec().

Referenced by load_module().

{
   return waitfor_exec(chan, data, &wait_for_silence);
}

Variable Documentation

app_noise

char* app_noise = "WaitForNoise"

static

Definition at line 131 of file app_waitforsilence.c.

Referenced by load_module(), and unload_module().

app_silence

char* app_silence = "WaitForSilence"

static

Definition at line 130 of file app_waitforsilence.c.

Referenced by load_module(), and unload_module().

wait_for_noise

const struct wait_type wait_for_noise

static

Definition at line 147 of file app_waitforsilence.c.

wait_for_silence

const struct wait_type wait_for_silence

static

Definition at line 140 of file app_waitforsilence.c.