Sat Mar 10 01:54:45 2012

Asterisk developer's documentation


app_waitforsilence.c File Reference

Wait for Silence More...

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

Go to the source code of this file.

Functions

static void __reg_module (void)
static void __unreg_module (void)
static int do_waiting (struct ast_channel *chan, int timereqd, time_t waitstart, int timeout, int wait_for_silence)
static int load_module (void)
static int unload_module (void)
static int waitfor_exec (struct ast_channel *chan, const char *data, int wait_for_silence)
static int waitfornoise_exec (struct ast_channel *chan, const char *data)
static int waitforsilence_exec (struct ast_channel *chan, const char *data)

Variables

static struct ast_module_info __mod_info = { .name = AST_MODULE, .flags = AST_MODFLAG_LOAD_ORDER , .description = "Wait For Silence" , .key = "This paragraph is copyright (c) 2006 by Digium, Inc. \In order for your module to load, it must return this \key via a function called \"key\". Any code which \includes this paragraph must be licensed under the GNU \General Public License version 2 or later (at your \option). In addition to Digium's general reservations \of rights, Digium expressly reserves the right to \allow other parties to license this paragraph under \different terms. Any use of Digium, Inc. trademarks or \logos (including \"Asterisk\" or \"Digium\") without \express written permission of Digium, Inc. is prohibited.\n" , .buildopt_sum = "88eaa8f5c1bd988bedd71113385e0886" , .load = load_module, .unload = unload_module, .load_pri = AST_MODPRI_DEFAULT, }
static char * app_noise = "WaitForNoise"
static char * app_silence = "WaitForSilence"
static struct ast_module_infoast_module_info = &__mod_info


Detailed Description

Wait for Silence

Author:
David C. Troy <dave@popvox.com>

Philipp Skadorov <skadorov@yahoo.com>

Definition in file app_waitforsilence.c.


Function Documentation

static void __reg_module ( void   )  [static]

Definition at line 276 of file app_waitforsilence.c.

static void __unreg_module ( void   )  [static]

Definition at line 276 of file app_waitforsilence.c.

static int do_waiting ( struct ast_channel chan,
int  timereqd,
time_t  waitstart,
int  timeout,
int  wait_for_silence 
) [static]

Definition at line 129 of file app_waitforsilence.c.

References ast_debug, ast_dsp_free(), ast_dsp_get_threshold_from_settings(), ast_dsp_new(), ast_dsp_noise(), ast_dsp_set_threshold(), ast_dsp_silence(), AST_FORMAT_SLINEAR, AST_FRAME_VOICE, ast_frfree, ast_getformatname(), ast_log(), ast_read(), ast_set_read_format(), ast_verb, ast_waitfor(), f, LOG_WARNING, ast_channel::name, pbx_builtin_setvar_helper(), ast_channel::readformat, and THRESHOLD_SILENCE.

Referenced by waitfor_exec().

00129                                                                                                                    {
00130    struct ast_frame *f = NULL;
00131    int dsptime = 0;
00132    int rfmt = 0;
00133    int res = 0;
00134    struct ast_dsp *sildet;  /* silence detector dsp */
00135    time_t now;
00136 
00137    /*Either silence or noise calc depending on wait_for_silence flag*/
00138    int (*ast_dsp_func)(struct ast_dsp*, struct ast_frame*, int*) =
00139             wait_for_silence ? ast_dsp_silence : ast_dsp_noise;
00140 
00141    rfmt = chan->readformat; /* Set to linear mode */
00142    if ((res = ast_set_read_format(chan, AST_FORMAT_SLINEAR)) < 0) {
00143       ast_log(LOG_WARNING, "Unable to set channel to linear mode, giving up\n");
00144       return -1;
00145    }
00146 
00147    /* Create the silence detector */
00148    if (!(sildet = ast_dsp_new())) {
00149       ast_log(LOG_WARNING, "Unable to create silence detector :(\n");
00150       return -1;
00151    }
00152    ast_dsp_set_threshold(sildet, ast_dsp_get_threshold_from_settings(THRESHOLD_SILENCE));
00153 
00154    /* Await silence... */
00155    for (;;) {
00156       /* Start with no silence received */
00157       dsptime = 0;
00158 
00159       res = ast_waitfor(chan, timereqd);
00160 
00161       /* Must have gotten a hangup; let's exit */
00162       if (res < 0) {
00163          pbx_builtin_setvar_helper(chan, "WAITSTATUS", "HANGUP");
00164          break;
00165       }
00166       
00167       /* We waited and got no frame; sounds like digital silence or a muted digital channel */
00168       if (res == 0) {
00169          dsptime = timereqd;
00170       } else {
00171          /* Looks like we did get a frame, so let's check it out */
00172          if (!(f = ast_read(chan))) {
00173             pbx_builtin_setvar_helper(chan, "WAITSTATUS", "HANGUP");
00174             break;
00175          }
00176          if (f->frametype == AST_FRAME_VOICE) {
00177             ast_dsp_func(sildet, f, &dsptime);
00178          }
00179          ast_frfree(f);
00180       }
00181 
00182       ast_verb(6, "Got %dms %s < %dms required\n", dsptime, wait_for_silence ? "silence" : "noise", timereqd);
00183 
00184       if (dsptime >= timereqd) {
00185          ast_verb(3, "Exiting with %dms %s >= %dms required\n", dsptime, wait_for_silence ? "silence" : "noise", timereqd);
00186          /* Ended happily with silence */
00187          res = 1;
00188          pbx_builtin_setvar_helper(chan, "WAITSTATUS", wait_for_silence ? "SILENCE" : "NOISE");
00189          ast_debug(1, "WAITSTATUS was set to %s\n", wait_for_silence ? "SILENCE" : "NOISE");
00190          break;
00191       }
00192 
00193       if (timeout && (difftime(time(&now), waitstart) >= timeout)) {
00194          pbx_builtin_setvar_helper(chan, "WAITSTATUS", "TIMEOUT");
00195          ast_debug(1, "WAITSTATUS was set to TIMEOUT\n");
00196          res = 0;
00197          break;
00198       }
00199    }
00200 
00201 
00202    if (rfmt && ast_set_read_format(chan, rfmt)) {
00203       ast_log(LOG_WARNING, "Unable to restore format %s to channel '%s'\n", ast_getformatname(rfmt), chan->name);
00204    }
00205    ast_dsp_free(sildet);
00206    return res;
00207 }

static int load_module ( void   )  [static]

Definition at line 267 of file app_waitforsilence.c.

References ast_register_application_xml, waitfornoise_exec(), and waitforsilence_exec().

00268 {
00269    int res;
00270 
00271    res = ast_register_application_xml(app_silence, waitforsilence_exec);
00272    res |= ast_register_application_xml(app_noise, waitfornoise_exec);
00273    return res;
00274 }

static int unload_module ( void   )  [static]

Definition at line 258 of file app_waitforsilence.c.

References ast_unregister_application().

00259 {
00260    int res;
00261    res = ast_unregister_application(app_silence);
00262    res |= ast_unregister_application(app_noise);
00263 
00264    return res;
00265 }

static int waitfor_exec ( struct ast_channel chan,
const char *  data,
int  wait_for_silence 
) [static]

Definition at line 209 of file app_waitforsilence.c.

References ast_channel::_state, ast_answer(), ast_channel_start_silence_generator(), ast_channel_stop_silence_generator(), ast_log(), ast_opt_transmit_silence, AST_STATE_UP, ast_verb, do_waiting(), and LOG_WARNING.

Referenced by waitfornoise_exec(), and waitforsilence_exec().

00210 {
00211    int res = 1;
00212    int timereqd = 1000;
00213    int timeout = 0;
00214    int iterations = 1, i;
00215    time_t waitstart;
00216    struct ast_silence_generator *silgen = NULL;
00217 
00218    if (chan->_state != AST_STATE_UP) {
00219       res = ast_answer(chan); /* Answer the channel */
00220    }
00221 
00222    if (!data || ( (sscanf(data, "%30d,%30d,%30d", &timereqd, &iterations, &timeout) != 3) &&
00223       (sscanf(data, "%30d,%30d", &timereqd, &iterations) != 2) &&
00224       (sscanf(data, "%30d", &timereqd) != 1) ) ) {
00225       ast_log(LOG_WARNING, "Using default value of 1000ms, 1 iteration, no timeout\n");
00226    }
00227 
00228    ast_verb(3, "Waiting %d time(s) for %d ms silence with %d timeout\n", iterations, timereqd, timeout);
00229 
00230    if (ast_opt_transmit_silence) {
00231       silgen = ast_channel_start_silence_generator(chan);
00232    }
00233    time(&waitstart);
00234    res = 1;
00235    for (i=0; (i<iterations) && (res == 1); i++) {
00236       res = do_waiting(chan, timereqd, waitstart, timeout, wait_for_silence);
00237    }
00238    if (silgen) {
00239       ast_channel_stop_silence_generator(chan, silgen);
00240    }
00241 
00242 
00243    if (res > 0)
00244       res = 0;
00245    return res;
00246 }

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

Definition at line 253 of file app_waitforsilence.c.

References waitfor_exec().

Referenced by load_module().

00254 {
00255    return waitfor_exec(chan, data, 0);
00256 }

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

Definition at line 248 of file app_waitforsilence.c.

References waitfor_exec().

Referenced by load_module().

00249 {
00250    return waitfor_exec(chan, data, 1);
00251 }


Variable Documentation

struct ast_module_info __mod_info = { .name = AST_MODULE, .flags = AST_MODFLAG_LOAD_ORDER , .description = "Wait For Silence" , .key = "This paragraph is copyright (c) 2006 by Digium, Inc. \In order for your module to load, it must return this \key via a function called \"key\". Any code which \includes this paragraph must be licensed under the GNU \General Public License version 2 or later (at your \option). In addition to Digium's general reservations \of rights, Digium expressly reserves the right to \allow other parties to license this paragraph under \different terms. Any use of Digium, Inc. trademarks or \logos (including \"Asterisk\" or \"Digium\") without \express written permission of Digium, Inc. is prohibited.\n" , .buildopt_sum = "88eaa8f5c1bd988bedd71113385e0886" , .load = load_module, .unload = unload_module, .load_pri = AST_MODPRI_DEFAULT, } [static]

Definition at line 276 of file app_waitforsilence.c.

char* app_noise = "WaitForNoise" [static]

Definition at line 127 of file app_waitforsilence.c.

char* app_silence = "WaitForSilence" [static]

Definition at line 126 of file app_waitforsilence.c.

struct ast_module_info* ast_module_info = &__mod_info [static]

Definition at line 276 of file app_waitforsilence.c.


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