Fri Aug 29 06:37:31 2008

Asterisk developer's documentation

---

app.c

Go to the documentation of this file.

/*
 * 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 Convenient Application Routines
 * 
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/time.h>
#include <signal.h>
#include <errno.h>
#include <unistd.h>
#include <dirent.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <regex.h>

#include "asterisk.h"

ASTERISK_FILE_VERSION(__FILE__, "$Revision: 74264 $")

#include "asterisk/channel.h"
#include "asterisk/pbx.h"
#include "asterisk/file.h"
#include "asterisk/app.h"
#include "asterisk/dsp.h"
#include "asterisk/logger.h"
#include "asterisk/options.h"
#include "asterisk/utils.h"
#include "asterisk/lock.h"
#include "asterisk/indications.h"
#include "asterisk/linkedlists.h"

#define MAX_OTHER_FORMATS 10

static AST_LIST_HEAD_STATIC(groups, ast_group_info);

/* !
This function presents a dialtone and reads an extension into 'collect' 
which must be a pointer to a **pre-initilized** array of char having a 
size of 'size' suitable for writing to.  It will collect no more than the smaller 
of 'maxlen' or 'size' minus the original strlen() of collect digits.
\return 0 if extension does not exist, 1 if extension exists
*/
int ast_app_dtget(struct ast_channel *chan, const char *context, char *collect, size_t size, int maxlen, int timeout) 
{
   struct tone_zone_sound *ts;
   int res=0, x=0;

   if(maxlen > size)
      maxlen = size;
   
   if(!timeout && chan->pbx)
      timeout = chan->pbx->dtimeout;
   else if(!timeout)
      timeout = 5;
   
   ts = ast_get_indication_tone(chan->zone,"dial");
   if (ts && ts->data[0])
      res = ast_playtones_start(chan, 0, ts->data, 0);
   else 
      ast_log(LOG_NOTICE,"Huh....? no dial for indications?\n");
   
   for (x = strlen(collect); strlen(collect) < maxlen; ) {
      res = ast_waitfordigit(chan, timeout);
      if (!ast_ignore_pattern(context, collect))
         ast_playtones_stop(chan);
      if (res < 1)
         break;
      if (res == '#')
         break;
      collect[x++] = res;
      if (!ast_matchmore_extension(chan, context, collect, 1, chan->cid.cid_num))
         break;
   }
   if (res >= 0) {
      if (ast_exists_extension(chan, context, collect, 1, chan->cid.cid_num))
         res = 1;
      else
         res = 0;
   }
   return res;
}



/*! \param timeout set timeout to 0 for "standard" timeouts. Set timeout to -1 for 
   "ludicrous time" (essentially never times out) */
int ast_app_getdata(struct ast_channel *c, char *prompt, char *s, int maxlen, int timeout)
{
   int res,to,fto;
   /* XXX Merge with full version? XXX */
   if (maxlen)
      s[0] = '\0';
   if (prompt) {
      res = ast_streamfile(c, prompt, c->language);
      if (res < 0)
         return res;
   }
   fto = c->pbx ? c->pbx->rtimeout * 1000 : 6000;
   to = c->pbx ? c->pbx->dtimeout * 1000 : 2000;

   if (timeout > 0) 
      fto = to = timeout;
   if (timeout < 0) 
      fto = to = 1000000000;
   res = ast_readstring(c, s, maxlen, to, fto, "#");
   return res;
}


int ast_app_getdata_full(struct ast_channel *c, char *prompt, char *s, int maxlen, int timeout, int audiofd, int ctrlfd)
{
   int res,to,fto;
   if (prompt) {
      res = ast_streamfile(c, prompt, c->language);
      if (res < 0)
         return res;
   }
   fto = 6000;
   to = 2000;
   if (timeout > 0) 
      fto = to = timeout;
   if (timeout < 0) 
      fto = to = 1000000000;
   res = ast_readstring_full(c, s, maxlen, to, fto, "#", audiofd, ctrlfd);
   return res;
}

int ast_app_getvoice(struct ast_channel *c, char *dest, char *dstfmt, char *prompt, int silence, int maxsec)
{
   int res;
   struct ast_filestream *writer;
   int rfmt;
   int totalms=0, total;
   
   struct ast_frame *f;
   struct ast_dsp *sildet;
   /* Play prompt if requested */
   if (prompt) {
      res = ast_streamfile(c, prompt, c->language);
      if (res < 0)
         return res;
      res = ast_waitstream(c,"");
      if (res < 0)
         return res;
   }
   rfmt = c->readformat;
   res = ast_set_read_format(c, AST_FORMAT_SLINEAR);
   if (res < 0) {
      ast_log(LOG_WARNING, "Unable to set to linear mode, giving up\n");
      return -1;
   }
   sildet = ast_dsp_new();
   if (!sildet) {
      ast_log(LOG_WARNING, "Unable to create silence detector :(\n");
      return -1;
   }
   writer = ast_writefile(dest, dstfmt, "Voice file", 0, 0, 0666);
   if (!writer) {
      ast_log(LOG_WARNING, "Unable to open file '%s' in format '%s' for writing\n", dest, dstfmt);
      ast_dsp_free(sildet);
      return -1;
   }
   for(;;) {
      if ((res = ast_waitfor(c, 2000)) < 0) {
         ast_log(LOG_NOTICE, "Waitfor failed while recording file '%s' format '%s'\n", dest, dstfmt);
         break;
      }
      if (res) {
         f = ast_read(c);
         if (!f) {
            ast_log(LOG_NOTICE, "Hungup while recording file '%s' format '%s'\n", dest, dstfmt);
            break;
         }
         if ((f->frametype == AST_FRAME_DTMF) && (f->subclass == '#')) {
            /* Ended happily with DTMF */
            ast_frfree(f);
            break;
         } else if (f->frametype == AST_FRAME_VOICE) {
            ast_dsp_silence(sildet, f, &total); 
            if (total > silence) {
               /* Ended happily with silence */
               ast_frfree(f);
               break;
            }
            totalms += f->samples / 8;
            if (totalms > maxsec * 1000) {
               /* Ended happily with too much stuff */
               ast_log(LOG_NOTICE, "Constraining voice on '%s' to %d seconds\n", c->name, maxsec);
               ast_frfree(f);
               break;
            }
            res = ast_writestream(writer, f);
            if (res < 0) {
               ast_log(LOG_WARNING, "Failed to write to stream at %s!\n", dest);
               ast_frfree(f);
               break;
            }
               
         }
         ast_frfree(f);
      }
   }
   res = ast_set_read_format(c, rfmt);
   if (res)
      ast_log(LOG_WARNING, "Unable to restore read format on '%s'\n", c->name);
   ast_dsp_free(sildet);
   ast_closestream(writer);
   return 0;
}

static int (*ast_has_voicemail_func)(const char *mailbox, const char *folder) = NULL;
static int (*ast_messagecount_func)(const char *mailbox, int *newmsgs, int *oldmsgs) = NULL;

void ast_install_vm_functions(int (*has_voicemail_func)(const char *mailbox, const char *folder),
               int (*messagecount_func)(const char *mailbox, int *newmsgs, int *oldmsgs))
{
   ast_has_voicemail_func = has_voicemail_func;
   ast_messagecount_func = messagecount_func;
}

void ast_uninstall_vm_functions(void)
{
   ast_has_voicemail_func = NULL;
   ast_messagecount_func = NULL;
}

int ast_app_has_voicemail(const char *mailbox, const char *folder)
{
   static int warned = 0;
   if (ast_has_voicemail_func)
      return ast_has_voicemail_func(mailbox, folder);

   if ((option_verbose > 2) && !warned) {
      ast_verbose(VERBOSE_PREFIX_3 "Message check requested for mailbox %s/folder %s but voicemail not loaded.\n", mailbox, folder ? folder : "INBOX");
      warned++;
   }
   return 0;
}


int ast_app_messagecount(const char *mailbox, int *newmsgs, int *oldmsgs)
{
   static int warned = 0;
   if (newmsgs)
      *newmsgs = 0;
   if (oldmsgs)
      *oldmsgs = 0;
   if (ast_messagecount_func)
      return ast_messagecount_func(mailbox, newmsgs, oldmsgs);

   if (!warned && (option_verbose > 2)) {
      warned++;
      ast_verbose(VERBOSE_PREFIX_3 "Message count requested for mailbox %s but voicemail not loaded.\n", mailbox);
   }

   return 0;
}

int ast_dtmf_stream(struct ast_channel *chan,struct ast_channel *peer,char *digits,int between) 
{
   char *ptr;
   int res = 0;
   struct ast_frame f;
   if (!between)
      between = 100;

   if (peer)
      res = ast_autoservice_start(peer);

   if (!res) {
      res = ast_waitfor(chan,100);
      if (res > -1) {
         for (ptr=digits; *ptr; ptr++) {
            if (*ptr == 'w') {
               res = ast_safe_sleep(chan, 500);
               if (res) 
                  break;
               continue;
            }
            memset(&f, 0, sizeof(f));
            f.frametype = AST_FRAME_DTMF;
            f.subclass = *ptr;
            f.src = "ast_dtmf_stream";
            if (strchr("0123456789*#abcdABCD",*ptr)==NULL) {
               ast_log(LOG_WARNING, "Illegal DTMF character '%c' in string. (0-9*#aAbBcCdD allowed)\n",*ptr);
            } else {
               res = ast_write(chan, &f);
               if (res) 
                  break;
               /* pause between digits */
               res = ast_safe_sleep(chan,between);
               if (res) 
                  break;
            }
         }
      }
      if (peer) {
         /* Stop autoservice on the peer channel, but don't overwrite any error condition 
            that has occurred previously while acting on the primary channel */  
         if (ast_autoservice_stop(peer) && !res)
            res = -1;
      }
   }
   return res;
}

struct linear_state {
   int fd;
   int autoclose;
   int allowoverride;
   int origwfmt;
};

static void linear_release(struct ast_channel *chan, void *params)
{
   struct linear_state *ls = params;
   if (ls->origwfmt && ast_set_write_format(chan, ls->origwfmt)) {
      ast_log(LOG_WARNING, "Unable to restore channel '%s' to format '%d'\n", chan->name, ls->origwfmt);
   }
   if (ls->autoclose)
      close(ls->fd);
   free(params);
}

static int linear_generator(struct ast_channel *chan, void *data, int len, int samples)
{
   struct ast_frame f;
   short buf[2048 + AST_FRIENDLY_OFFSET / 2];
   struct linear_state *ls = data;
   int res;
   len = samples * 2;
   if (len > sizeof(buf) - AST_FRIENDLY_OFFSET) {
      ast_log(LOG_WARNING, "Can't generate %d bytes of data!\n" ,len);
      len = sizeof(buf) - AST_FRIENDLY_OFFSET;
   }
   memset(&f, 0, sizeof(f));
   res = read(ls->fd, buf + AST_FRIENDLY_OFFSET/2, len);
   if (res > 0) {
      f.frametype = AST_FRAME_VOICE;
      f.subclass = AST_FORMAT_SLINEAR;
      f.data = buf + AST_FRIENDLY_OFFSET/2;
      f.datalen = res;
      f.samples = res / 2;
      f.offset = AST_FRIENDLY_OFFSET;
      ast_write(chan, &f);
      if (res == len)
         return 0;
   }
   return -1;
}

static void *linear_alloc(struct ast_channel *chan, void *params)
{
   struct linear_state *ls;
   /* In this case, params is already malloc'd */
   if (params) {
      ls = params;
      if (ls->allowoverride)
         ast_set_flag(chan, AST_FLAG_WRITE_INT);
      else
         ast_clear_flag(chan, AST_FLAG_WRITE_INT);
      ls->origwfmt = chan->writeformat;
      if (ast_set_write_format(chan, AST_FORMAT_SLINEAR)) {
         ast_log(LOG_WARNING, "Unable to set '%s' to linear format (write)\n", chan->name);
         free(ls);
         ls = params = NULL;
      }
   }
   return params;
}

static struct ast_generator linearstream = 
{
   alloc: linear_alloc,
   release: linear_release,
   generate: linear_generator,
};

int ast_linear_stream(struct ast_channel *chan, const char *filename, int fd, int allowoverride)
{
   struct linear_state *lin;
   char tmpf[256];
   int res = -1;
   int autoclose = 0;
   if (fd < 0) {
      if (ast_strlen_zero(filename))
         return -1;
      autoclose = 1;
      if (filename[0] == '/') 
         ast_copy_string(tmpf, filename, sizeof(tmpf));
      else
         snprintf(tmpf, sizeof(tmpf), "%s/%s/%s", (char *)ast_config_AST_VAR_DIR, "sounds", filename);
      fd = open(tmpf, O_RDONLY);
      if (fd < 0){
         ast_log(LOG_WARNING, "Unable to open file '%s': %s\n", tmpf, strerror(errno));
         return -1;
      }
   }
   lin = malloc(sizeof(struct linear_state));
   if (lin) {
      memset(lin, 0, sizeof(lin));
      lin->fd = fd;
      lin->allowoverride = allowoverride;
      lin->autoclose = autoclose;
      res = ast_activate_generator(chan, &linearstream, lin);
   }
   return res;
}

int ast_control_streamfile(struct ast_channel *chan, const char *file,
            const char *fwd, const char *rev,
            const char *stop, const char *pause,
            const char *restart, int skipms) 
{
   char *breaks = NULL;
   char *end = NULL;
   int blen = 2;
   int res;
   long pause_restart_point = 0;

   if (stop)
      blen += strlen(stop);
   if (pause)
      blen += strlen(pause);
   if (restart)
      blen += strlen(restart);

   if (blen > 2) {
      breaks = alloca(blen + 1);
      breaks[0] = '\0';
      if (stop)
         strcat(breaks, stop);
      if (pause)
         strcat(breaks, pause);
      if (restart)
         strcat(breaks, restart);
   }
   if (chan->_state != AST_STATE_UP)
      res = ast_answer(chan);

   if (file) {
      if ((end = strchr(file,':'))) {
         if (!strcasecmp(end, ":end")) {
            *end = '\0';
            end++;
         }
      }
   }

   for (;;) {
      ast_stopstream(chan);
      res = ast_streamfile(chan, file, chan->language);
      if (!res) {
         if (pause_restart_point) {
            ast_seekstream(chan->stream, pause_restart_point, SEEK_SET);
            pause_restart_point = 0;
         }
         else if (end) {
            ast_seekstream(chan->stream, 0, SEEK_END);
            end = NULL;
         };
         res = ast_waitstream_fr(chan, breaks, fwd, rev, skipms);
      }

      if (res < 1)
         break;

      /* We go at next loop if we got the restart char */
      if (restart && strchr(restart, res)) {
         ast_log(LOG_DEBUG, "we'll restart the stream here at next loop\n");
         pause_restart_point = 0;
         continue;
      }

      if (pause && strchr(pause, res)) {
         pause_restart_point = ast_tellstream(chan->stream);
         for (;;) {
            ast_stopstream(chan);
            res = ast_waitfordigit(chan, 1000);
            if (!res)
               continue;
            else if (res == -1 || strchr(pause, res) || (stop && strchr(stop, res)))
               break;
         }
         if (res == *pause) {
            res = 0;
            continue;
         }
      }

      if (res == -1)
         break;

      /* if we get one of our stop chars, return it to the calling function */
      if (stop && strchr(stop, res))
         break;
   }

   ast_stopstream(chan);

   return res;
}

int ast_play_and_wait(struct ast_channel *chan, const char *fn)
{
   int d;
   d = ast_streamfile(chan, fn, chan->language);
   if (d)
      return d;
   d = ast_waitstream(chan, AST_DIGIT_ANY);
   ast_stopstream(chan);
   return d;
}

static int global_silence_threshold = 128;
static int global_maxsilence = 0;

int ast_play_and_record_full(struct ast_channel *chan, const char *playfile, const char *recordfile, int maxtime, const char *fmt, int *duration, int silencethreshold, int maxsilence, const char *path, const char *acceptdtmf, const char *canceldtmf)
{
   int d;
   char *fmts;
   char comment[256];
   int x, fmtcnt=1, res=-1,outmsg=0;
   struct ast_frame *f;
   struct ast_filestream *others[MAX_OTHER_FORMATS];
   char *sfmt[MAX_OTHER_FORMATS];
   char *stringp=NULL;
   time_t start, end;
   struct ast_dsp *sildet=NULL;     /* silence detector dsp */
   int totalsilence = 0;
   int dspsilence = 0;
   int rfmt=0;
   struct ast_silence_generator *silgen = NULL;

   if (silencethreshold < 0)
      silencethreshold = global_silence_threshold;

   if (maxsilence < 0)
      maxsilence = global_maxsilence;

   /* barf if no pointer passed to store duration in */
   if (duration == NULL) {
      ast_log(LOG_WARNING, "Error play_and_record called without duration pointer\n");
      return -1;
   }

   ast_log(LOG_DEBUG,"play_and_record: %s, %s, '%s'\n", playfile ? playfile : "<None>", recordfile, fmt);
   snprintf(comment,sizeof(comment),"Playing %s, Recording to: %s on %s\n", playfile ? playfile : "<None>", recordfile, chan->name);

   if (playfile) {
      d = ast_play_and_wait(chan, playfile);
      if (d > -1)
         d = ast_streamfile(chan, "beep",chan->language);
      if (!d)
         d = ast_waitstream(chan,"");
      if (d < 0)
         return -1;
   }

   fmts = ast_strdupa(fmt);

   stringp=fmts;
   strsep(&stringp, "|");
   ast_log(LOG_DEBUG,"Recording Formats: sfmts=%s\n", fmts);
   sfmt[0] = ast_strdupa(fmts);

   while((fmt = strsep(&stringp, "|"))) {
      if (fmtcnt > MAX_OTHER_FORMATS - 1) {
         ast_log(LOG_WARNING, "Please increase MAX_OTHER_FORMATS in app.c\n");
         break;
      }
      sfmt[fmtcnt++] = ast_strdupa(fmt);
   }

   time(&start);
   end=start;  /* pre-initialize end to be same as start in case we never get into loop */
   for (x=0;x<fmtcnt;x++) {
      others[x] = ast_writefile(recordfile, sfmt[x], comment, O_TRUNC, 0, 0700);
      ast_verbose( VERBOSE_PREFIX_3 "x=%d, open writing:  %s format: %s, %p\n", x, recordfile, sfmt[x], others[x]);

      if (!others[x]) {
         break;
      }
   }

   if (path)
      ast_unlock_path(path);

   if (maxsilence > 0) {
      sildet = ast_dsp_new(); /* Create the silence detector */
      if (!sildet) {
         ast_log(LOG_WARNING, "Unable to create silence detector :(\n");
         return -1;
      }
      ast_dsp_set_threshold(sildet, silencethreshold);
      rfmt = chan->readformat;
      res = ast_set_read_format(chan, AST_FORMAT_SLINEAR);
      if (res < 0) {
         ast_log(LOG_WARNING, "Unable to set to linear mode, giving up\n");
         ast_dsp_free(sildet);
         return -1;
      }
   }

   /* Request a video update */
   ast_indicate(chan, AST_CONTROL_VIDUPDATE);

   if (option_transmit_silence_during_record)
      silgen = ast_channel_start_silence_generator(chan);

   if (x == fmtcnt) {
   /* Loop forever, writing the packets we read to the writer(s), until
      we read a # or get a hangup */
      f = NULL;
      for(;;) {
         res = ast_waitfor(chan, 2000);
         if (!res) {
            ast_log(LOG_DEBUG, "One waitfor failed, trying another\n");
            /* Try one more time in case of masq */
            res = ast_waitfor(chan, 2000);
            if (!res) {
               ast_log(LOG_WARNING, "No audio available on %s??\n", chan->name);
               res = -1;
            }
         }

         if (res < 0) {
            f = NULL;
            break;
         }
         f = ast_read(chan);
         if (!f)
            break;
         if (f->frametype == AST_FRAME_VOICE) {
            /* write each format */
            for (x=0;x<fmtcnt;x++) {
               res = ast_writestream(others[x], f);
            }

            /* Silence Detection */
            if (maxsilence > 0) {
               dspsilence = 0;
               ast_dsp_silence(sildet, f, &dspsilence);
               if (dspsilence)
                  totalsilence = dspsilence;
               else
                  totalsilence = 0;

               if (totalsilence > maxsilence) {
                  /* Ended happily with silence */
                  if (option_verbose > 2)
                     ast_verbose( VERBOSE_PREFIX_3 "Recording automatically stopped after a silence of %d seconds\n", totalsilence/1000);
                  ast_frfree(f);
                  res = 'S';
                  outmsg=2;
                  break;
               }
            }
            /* Exit on any error */
            if (res) {
               ast_log(LOG_WARNING, "Error writing frame\n");
               ast_frfree(f);
               break;
            }
         } else if (f->frametype == AST_FRAME_VIDEO) {
            /* Write only once */
            ast_writestream(others[0], f);
         } else if (f->frametype == AST_FRAME_DTMF) {
            if (strchr(acceptdtmf, f->subclass)) {
               if (option_verbose > 2)
                  ast_verbose(VERBOSE_PREFIX_3 "User ended message by pressing %c\n", f->subclass);
               res = f->subclass;
               outmsg = 2;
               ast_frfree(f);
               break;
            }
            if (strchr(canceldtmf, f->subclass)) {
               if (option_verbose > 2)
                  ast_verbose(VERBOSE_PREFIX_3 "User cancelled message by pressing %c\n", f->subclass);
               res = f->subclass;
               outmsg = 0;
               ast_frfree(f);
               break;
            }
         }
         if (maxtime) {
            time(&end);
            if (maxtime < (end - start)) {
               if (option_verbose > 2)
                  ast_verbose( VERBOSE_PREFIX_3 "Took too long, cutting it short...\n");
               outmsg = 2;
               res = 't';
               ast_frfree(f);
               break;
            }
         }
         ast_frfree(f);
      }
      if (end == start) time(&end);
      if (!f) {
         if (option_verbose > 2)
            ast_verbose( VERBOSE_PREFIX_3 "User hung up\n");
         res = -1;
         outmsg=1;
      }
   } else {
      ast_log(LOG_WARNING, "Error creating writestream '%s', format '%s'\n", recordfile, sfmt[x]);
   }

   if (silgen)
      ast_channel_stop_silence_generator(chan, silgen);

   *duration = end - start;

   for (x=0;x<fmtcnt;x++) {
      if (!others[x])
         break;
      if (res > 0) {
         if (totalsilence)
            ast_stream_rewind(others[x], totalsilence-200);
         else
            ast_stream_rewind(others[x], 200);
      }
      ast_truncstream(others[x]);
      ast_closestream(others[x]);
   }
   if (rfmt) {
      if (ast_set_read_format(chan, rfmt)) {
         ast_log(LOG_WARNING, "Unable to restore format %s to channel '%s'\n", ast_getformatname(rfmt), chan->name);
      }
   }
   if (outmsg > 1) {
      /* Let them know recording is stopped */
      if(!ast_streamfile(chan, "auth-thankyou", chan->language))
         ast_waitstream(chan, "");
   }
   if (sildet)
      ast_dsp_free(sildet);
   return res;
}

static char default_acceptdtmf[] = "#";
static char default_canceldtmf[] = "0";

int ast_play_and_record(struct ast_channel *chan, const char *playfile, const char *recordfile, int maxtime, const char *fmt, int *duration, int silencethreshold, int maxsilence, const char *path)
{
   return ast_play_and_record_full(chan, playfile, recordfile, maxtime, fmt, duration, silencethreshold, maxsilence, path, default_acceptdtmf, default_canceldtmf);
}

int ast_play_and_prepend(struct ast_channel *chan, char *playfile, char *recordfile, int maxtime, char *fmt, int *duration, int beep, int silencethreshold, int maxsilence)
{
   int d = 0;
   char *fmts;
   char comment[256];
   int x, fmtcnt=1, res=-1,outmsg=0;
   struct ast_frame *f;
   struct ast_filestream *others[MAX_OTHER_FORMATS];
   struct ast_filestream *realfiles[MAX_OTHER_FORMATS];
   char *sfmt[MAX_OTHER_FORMATS];
   char *stringp=NULL;
   time_t start, end;
   struct ast_dsp *sildet;    /* silence detector dsp */
   int totalsilence = 0;
   int dspsilence = 0;
   int rfmt=0; 
   char prependfile[80];
   
   if (silencethreshold < 0)
      silencethreshold = global_silence_threshold;

   if (maxsilence < 0)
      maxsilence = global_maxsilence;

   /* barf if no pointer passed to store duration in */
   if (duration == NULL) {
      ast_log(LOG_WARNING, "Error play_and_prepend called without duration pointer\n");
      return -1;
   }

   ast_log(LOG_DEBUG,"play_and_prepend: %s, %s, '%s'\n", playfile ? playfile : "<None>", recordfile, fmt);
   snprintf(comment,sizeof(comment),"Playing %s, Recording to: %s on %s\n", playfile ? playfile : "<None>", recordfile, chan->name);

   if (playfile || beep) { 
      if (!beep)
         d = ast_play_and_wait(chan, playfile);
      if (d > -1)
         d = ast_streamfile(chan, "beep",chan->language);
      if (!d)
         d = ast_waitstream(chan,"");
      if (d < 0)
         return -1;
   }
   ast_copy_string(prependfile, recordfile, sizeof(prependfile)); 
   strncat(prependfile, "-prepend", sizeof(prependfile) - strlen(prependfile) - 1);
         
   fmts = ast_strdupa(fmt);
   
   stringp=fmts;
   strsep(&stringp, "|");
   ast_log(LOG_DEBUG,"Recording Formats: sfmts=%s\n", fmts);   
   sfmt[0] = ast_strdupa(fmts);
   
   while((fmt = strsep(&stringp, "|"))) {
      if (fmtcnt > MAX_OTHER_FORMATS - 1) {
         ast_log(LOG_WARNING, "Please increase MAX_OTHER_FORMATS in app.c\n");
         break;
      }
      sfmt[fmtcnt++] = ast_strdupa(fmt);
   }

   time(&start);
   end=start;  /* pre-initialize end to be same as start in case we never get into loop */
   for (x=0;x<fmtcnt;x++) {
      others[x] = ast_writefile(prependfile, sfmt[x], comment, O_TRUNC, 0, 0700);
      ast_verbose( VERBOSE_PREFIX_3 "x=%d, open writing:  %s format: %s, %p\n", x, prependfile, sfmt[x], others[x]);
      if (!others[x]) {
         break;
      }
   }
   
   sildet = ast_dsp_new(); /* Create the silence detector */
   if (!sildet) {
      ast_log(LOG_WARNING, "Unable to create silence detector :(\n");
      return -1;
   }
   ast_dsp_set_threshold(sildet, silencethreshold);

   if (maxsilence > 0) {
      rfmt = chan->readformat;
      res = ast_set_read_format(chan, AST_FORMAT_SLINEAR);
      if (res < 0) {
         ast_log(LOG_WARNING, "Unable to set to linear mode, giving up\n");
         ast_dsp_free(sildet);
         return -1;
      }
   }
                  
   if (x == fmtcnt) {
   /* Loop forever, writing the packets we read to the writer(s), until
      we read a # or get a hangup */
      f = NULL;
      for(;;) {
         res = ast_waitfor(chan, 2000);
         if (!res) {
            ast_log(LOG_DEBUG, "One waitfor failed, trying another\n");
            /* Try one more time in case of masq */
            res = ast_waitfor(chan, 2000);
            if (!res) {
               ast_log(LOG_WARNING, "No audio available on %s??\n", chan->name);
               res = -1;
            }
         }
         
         if (res < 0) {
            f = NULL;
            break;
         }
         f = ast_read(chan);
         if (!f)
            break;
         if (f->frametype == AST_FRAME_VOICE) {
            /* write each format */
            for (x=0;x<fmtcnt;x++) {
               if (!others[x])
                  break;
               res = ast_writestream(others[x], f);
            }
            
            /* Silence Detection */
            if (maxsilence > 0) {
               dspsilence = 0;
               ast_dsp_silence(sildet, f, &dspsilence);
               if (dspsilence)
                  totalsilence = dspsilence;
               else
                  totalsilence = 0;
               
               if (totalsilence > maxsilence) {
               /* Ended happily with silence */
               if (option_verbose > 2) 
                  ast_verbose( VERBOSE_PREFIX_3 "Recording automatically stopped after a silence of %d seconds\n", totalsilence/1000);
               ast_frfree(f);
               res = 'S';
               outmsg=2;
               break;
               }
            }
            /* Exit on any error */
            if (res) {
               ast_log(LOG_WARNING, "Error writing frame\n");
               ast_frfree(f);
               break;
            }
         } else if (f->frametype == AST_FRAME_VIDEO) {
            /* Write only once */
            ast_writestream(others[0], f);
         } else if (f->frametype == AST_FRAME_DTMF) {
            /* stop recording with any digit */
            if (option_verbose > 2) 
               ast_verbose( VERBOSE_PREFIX_3 "User ended message by pressing %c\n", f->subclass);
            res = 't';
            outmsg = 2;
            ast_frfree(f);
            break;
         }
         if (maxtime) {
            time(&end);
            if (maxtime < (end - start)) {
               if (option_verbose > 2)
                  ast_verbose( VERBOSE_PREFIX_3 "Took too long, cutting it short...\n");
               res = 't';
               outmsg=2;
               ast_frfree(f);
               break;
            }
         }
         ast_frfree(f);
      }
      if (end == start) time(&end);
      if (!f) {
         if (option_verbose > 2) 
            ast_verbose( VERBOSE_PREFIX_3 "User hung up\n");
         res = -1;
         outmsg=1;
#if 0
         /* delete all the prepend files */
         for (x=0;x<fmtcnt;x++) {
            if (!others[x])
               break;
            ast_closestream(others[x]);
            ast_filedelete(prependfile, sfmt[x]);
         }
#endif
      }
   } else {
      ast_log(LOG_WARNING, "Error creating writestream '%s', format '%s'\n", prependfile, sfmt[x]); 
   }
   ast_dsp_free(sildet);
   *duration = end - start;
#if 0
   if (outmsg > 1) {
#else
   if (outmsg) {
#endif
      struct ast_frame *fr;
      for (x=0;x<fmtcnt;x++) {
         snprintf(comment, sizeof(comment), "Opening the real file %s.%s\n", recordfile, sfmt[x]);
         realfiles[x] = ast_readfile(recordfile, sfmt[x], comment, O_RDONLY, 0, 0);
         if (!others[x] || !realfiles[x])
            break;
         if (totalsilence)
            ast_stream_rewind(others[x], totalsilence-200);
         else
            ast_stream_rewind(others[x], 200);
         ast_truncstream(others[x]);
         /* add the original file too */
         while ((fr = ast_readframe(realfiles[x]))) {
            ast_writestream(others[x],fr);
         }
         ast_closestream(others[x]);
         ast_closestream(realfiles[x]);
         ast_filerename(prependfile, recordfile, sfmt[x]);
#if 0
         ast_verbose("Recording Format: sfmts=%s, prependfile %s, recordfile %s\n", sfmt[x],prependfile,recordfile);
#endif
         ast_filedelete(prependfile, sfmt[x]);
      }
   }
   if (rfmt) {
      if (ast_set_read_format(chan, rfmt)) {
         ast_log(LOG_WARNING, "Unable to restore format %s to channel '%s'\n", ast_getformatname(rfmt), chan->name);
      }
   }
   if (outmsg) {
      if (outmsg > 1) {
         /* Let them know it worked */
         ast_streamfile(chan, "auth-thankyou", chan->language);
         ast_waitstream(chan, "");
      }
   }  
   return res;
}

/* Channel group core functions */

int ast_app_group_split_group(char *data, char *group, int group_max, char *category, int category_max)
{
   int res=0;
   char tmp[256];
   char *grp=NULL, *cat=NULL;

   if (!ast_strlen_zero(data)) {
      ast_copy_string(tmp, data, sizeof(tmp));
      grp = tmp;
      cat = strchr(tmp, '@');
      if (cat) {
         *cat = '\0';
         cat++;
      }
   }

   if (!ast_strlen_zero(grp))
      ast_copy_string(group, grp, group_max);
   else
      res = -1;

   if (!ast_strlen_zero(cat))
      ast_copy_string(category, cat, category_max);

   return res;
}

int ast_app_group_set_channel(struct ast_channel *chan, char *data)
{
   int res = 0;
   char group[80] = "", category[80] = "";
   struct ast_group_info *gi = NULL;
   size_t len = 0;

   if (ast_app_group_split_group(data, group, sizeof(group), category, sizeof(category)))
      return -1;

   /* Calculate memory we will need if this is new */
   len = sizeof(*gi) + strlen(group) + 1;
   if (!ast_strlen_zero(category))
      len += strlen(category) + 1;

   AST_LIST_LOCK(&groups);
   AST_LIST_TRAVERSE_SAFE_BEGIN(&groups, gi, list) {
      if ((gi->chan == chan) && ((ast_strlen_zero(category) && ast_strlen_zero(gi->category)) || (!ast_strlen_zero(gi->category) && !strcasecmp(gi->category, category)))) {
         AST_LIST_REMOVE_CURRENT(&groups, list);
         free(gi);
         break;
      }
   }
   AST_LIST_TRAVERSE_SAFE_END

   if ((gi = calloc(1, len))) {
      gi->chan = chan;
      gi->group = (char *) gi + sizeof(*gi);
      strcpy(gi->group, group);
      if (!ast_strlen_zero(category)) {
         gi->category = (char *) gi + sizeof(*gi) + strlen(group) + 1;
         strcpy(gi->category, category);
      }
      AST_LIST_INSERT_TAIL(&groups, gi, list);
   } else {
      res = -1;
   }

   AST_LIST_UNLOCK(&groups);

   return res;
}

int ast_app_group_get_count(