apps/app_chanisavail.c

   1 /*
   2  * Asterisk -- A telephony toolkit for Linux.
   3  *
   4  * Check if Channel is Available
   5  *
   6  * Copyright (C) 2003, Digium
   7  *
   8  * Mark Spencer <markster@digium.com>
   9  * James Golovich <james@gnuinter.net>
  10  *
  11  * This program is free software, distributed under the terms of
  12  * the GNU General Public License
  13  *
  14  */
  15
  16 #include <asterisk/lock.h>
  17 #include <asterisk/file.h>
  18 #include <asterisk/logger.h>
  19 #include <asterisk/channel.h>
  20 #include <asterisk/pbx.h>
  21 #include <asterisk/module.h>
  22 #include <asterisk/app.h>
  23 #include <stdlib.h>
  24 #include <unistd.h>
  25 #include <errno.h>
  26 #include <string.h>
  27 #include <stdlib.h>
  28 #include <sys/ioctl.h>
  29
  30 #include <pthread.h>
  31
  32 static char *tdesc = "Check if channel is available";
  33
  34 static char *app = "ChanIsAvail";
  35
  36 static char *synopsis = "Check if channel is available";
  37
  38 static char *descrip =
  39 "  ChanIsAvail(Technology/resource[&Technology2/resource2...]): \n"
  40 "Checks is any of the requested channels are available.  If none\n"
  41 "of the requested channels are available the new priority will be\n"
  42 "n+101 (unless such a priority does not exist or on error, in which\n"
  43 "case ChanIsAvail will return -1).  If any of the requested channels\n"
  44 "are available, the next priority will be n+1, the channel variable\n"
  45 "${AVAILCHAN} will be set to the name of the available channel and\n"
  46 "the ChanIsAvail app will return 0.  ${AVAILORIGCHAN} is\n"
  47 "the canonical channel name that was used to create the channel.\n";
  48
  49 STANDARD_LOCAL_USER;
  50
  51 LOCAL_USER_DECL;
  52
  53 static int chanavail_exec(struct ast_channel *chan, void *data)
  54 {
  55         int res=-1;
  56         struct localuser *u;
  57         char info[512], tmp[512], *peers, *tech, *number, *rest, *cur;
  58         struct ast_channel *tempchan;
  59
  60         if (!data) {
  61                 ast_log(LOG_WARNING, "ChanIsAvail requires an argument (Zap/1&Zap/2)\n");
  62                 return -1;
  63         }
  64         LOCAL_USER_ADD(u);
  65
  66         strncpy(info, (char *)data, sizeof(info)-1);
  67         peers = info;
  68         if (peers) {
  69                 cur = peers;
  70                 do {
  71                         /* remember where to start next time */
  72                         rest = strchr(cur, '&');
  73                         if (rest) {
  74                                 *rest = 0;
  75                                 rest++;
  76                         }
  77                         tech = cur;
  78                         number = strchr(tech, '/');
  79                         if (!number) {
  80                                 ast_log(LOG_WARNING, "ChanIsAvail argument takes format ([technology]/[device])\n");
  81                                 return -1;
  82                         }
  83                         *number = '\0';
  84                         number++;
  85                         if ((tempchan = ast_request(tech, chan->nativeformats, number))) {
  86                                         pbx_builtin_setvar_helper(chan, "AVAILCHAN", tempchan->name);
  87                                         /* Store the originally used channel too */
  88                                         snprintf(tmp, sizeof(tmp), "%s/%s", tech, number);
  89                                         pbx_builtin_setvar_helper(chan, "AVAILORIGCHAN", tmp);
  90                                         ast_hangup(tempchan);
  91                                         tempchan = NULL;
  92                                         res = 1;
  93                                         break;
  94                         }
  95                         cur = rest;
  96                 } while (cur);
  97         }
  98
  99         if (res < 1) {
 100                 pbx_builtin_setvar_helper(chan, "AVAILCHAN", "");
 101                 pbx_builtin_setvar_helper(chan, "AVAILORIGCHAN", "");
 102                 if (ast_exists_extension(chan, chan->context, chan->exten, chan->priority + 101, chan->callerid))
 103                         chan->priority+=100;
 104                 else
 105                         return -1;
 106         }
 107
 108         LOCAL_USER_REMOVE(u);
 109         return 0;
 110 }
 111
 112 int unload_module(void)
 113 {
 114         STANDARD_HANGUP_LOCALUSERS;
 115         return ast_unregister_application(app);
 116 }
 117
 118 int load_module(void)
 119 {
 120         return ast_register_application(app, chanavail_exec, synopsis, descrip);
 121 }
 122
 123 char *description(void)
 124 {
 125         return tdesc;
 126 }
 127
 128 int usecount(void)
 129 {
 130         int res;
 131         STANDARD_USECOUNT(res);
 132         return res;
 133 }
 134
 135 char *key()
 136 {
 137         return ASTERISK_GPL_KEY;
 138 }