bridges/bridge_builtin_features.c

   1 /*
   2  * Asterisk -- An open source telephony toolkit.
   3  *
   4  * Copyright (C) 2009, Digium, Inc.
   5  *
   6  * Joshua Colp <jcolp@digium.com>
   7  *
   8  * See http://www.asterisk.org for more information about
   9  * the Asterisk project. Please do not directly contact
  10  * any of the maintainers of this project for assistance;
  11  * the project provides a web site, mailing lists and IRC
  12  * channels for your use.
  13  *
  14  * This program is free software, distributed under the terms of
  15  * the GNU General Public License Version 2. See the LICENSE file
  16  * at the top of the source tree.
  17  */
  18
  19 /*! \file
  20  *
  21  * \brief Built in bridging features
  22  *
  23  * \author Joshua Colp <jcolp@digium.com>
  24  *
  25  * \ingroup bridges
  26  */
  27
  28 /*** MODULEINFO
  29         <support_level>core</support_level>
  30  ***/
  31
  32 #include "asterisk.h"
  33
  34 ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
  35
  36 #include <stdio.h>
  37 #include <stdlib.h>
  38 #include <string.h>
  39 #include <sys/types.h>
  40 #include <sys/stat.h>
  41
  42 #include "asterisk/module.h"
  43 #include "asterisk/channel.h"
  44 #include "asterisk/bridge.h"
  45 #include "asterisk/bridge_technology.h"
  46 #include "asterisk/frame.h"
  47 #include "asterisk/file.h"
  48 #include "asterisk/app.h"
  49 #include "asterisk/astobj2.h"
  50 #include "asterisk/pbx.h"
  51 #include "asterisk/parking.h"
  52 #include "asterisk/features_config.h"
  53 #include "asterisk/monitor.h"
  54 #include "asterisk/mixmonitor.h"
  55 #include "asterisk/audiohook.h"
  56 #include "asterisk/causes.h"
  57
  58 enum set_touch_variables_res {
  59         SET_TOUCH_SUCCESS,
  60         SET_TOUCH_UNSET,
  61         SET_TOUCH_ALLOC_FAILURE,
  62 };
  63
  64 static void set_touch_variable(enum set_touch_variables_res *res, struct ast_channel *chan, const char *var_name, char **touch)
  65 {
  66         const char *c_touch;
  67
  68         if (*res == SET_TOUCH_ALLOC_FAILURE) {
  69                 return;
  70         }
  71         c_touch = pbx_builtin_getvar_helper(chan, var_name);
  72         if (!ast_strlen_zero(c_touch)) {
  73                 *touch = ast_strdup(c_touch);
  74                 if (!*touch) {
  75                         *res = SET_TOUCH_ALLOC_FAILURE;
  76                 } else {
  77                         *res = SET_TOUCH_SUCCESS;
  78                 }
  79         }
  80 }
  81
  82 static enum set_touch_variables_res set_touch_variables(struct ast_channel *chan, int is_mixmonitor, char **touch_format, char **touch_monitor, char **touch_monitor_prefix)
  83 {
  84         enum set_touch_variables_res res = SET_TOUCH_UNSET;
  85         const char *var_format;
  86         const char *var_monitor;
  87         const char *var_prefix;
  88
  89         SCOPED_CHANNELLOCK(lock, chan);
  90
  91         if (is_mixmonitor) {
  92                 var_format = "TOUCH_MIXMONITOR_FORMAT";
  93                 var_monitor = "TOUCH_MIXMONITOR";
  94                 var_prefix = "TOUCH_MIXMONITOR_PREFIX";
  95         } else {
  96                 var_format = "TOUCH_MONITOR_FORMAT";
  97                 var_monitor = "TOUCH_MONITOR";
  98                 var_prefix = "TOUCH_MONITOR_PREFIX";
  99         }
 100         set_touch_variable(&res, chan, var_format, touch_format);
 101         set_touch_variable(&res, chan, var_monitor, touch_monitor);
 102         set_touch_variable(&res, chan, var_prefix, touch_monitor_prefix);
 103
 104         return res;
 105 }
 106
 107 static void stop_automonitor(struct ast_bridge_channel *bridge_channel, struct ast_channel *peer_chan, struct ast_features_general_config *features_cfg, const char *stop_message)
 108 {
 109         ast_verb(4, "AutoMonitor used to stop recording call.\n");
 110
 111         ast_channel_lock(peer_chan);
 112         if (ast_channel_monitor(peer_chan)) {
 113                 if (ast_channel_monitor(peer_chan)->stop(peer_chan, 1)) {
 114                         ast_verb(4, "Cannot stop AutoMonitor for %s\n", ast_channel_name(bridge_channel->chan));
 115                         if (features_cfg && !(ast_strlen_zero(features_cfg->recordingfailsound))) {
 116                                 ast_bridge_channel_queue_playfile(bridge_channel, NULL, features_cfg->recordingfailsound, NULL);
 117                         }
 118                         ast_channel_unlock(peer_chan);
 119                         return;
 120                 }
 121         } else {
 122                 /* Something else removed the Monitor before we got to it. */
 123                 ast_channel_unlock(peer_chan);
 124                 return;
 125         }
 126
 127         ast_channel_unlock(peer_chan);
 128
 129         if (features_cfg && !(ast_strlen_zero(features_cfg->courtesytone))) {
 130                 ast_bridge_channel_queue_playfile(bridge_channel, NULL, features_cfg->courtesytone, NULL);
 131                 ast_bridge_channel_write_playfile(bridge_channel, NULL, features_cfg->courtesytone, NULL);
 132         }
 133
 134         if (!ast_strlen_zero(stop_message)) {
 135                 ast_bridge_channel_queue_playfile(bridge_channel, NULL, stop_message, NULL);
 136                 ast_bridge_channel_write_playfile(bridge_channel, NULL, stop_message, NULL);
 137         }
 138 }
 139
 140 static void start_automonitor(struct ast_bridge_channel *bridge_channel, struct ast_channel *peer_chan, struct ast_features_general_config *features_cfg, const char *start_message)
 141 {
 142         char *touch_filename;
 143         size_t len;
 144         int x;
 145         enum set_touch_variables_res set_touch_res;
 146
 147         RAII_VAR(char *, touch_format, NULL, ast_free);
 148         RAII_VAR(char *, touch_monitor, NULL, ast_free);
 149         RAII_VAR(char *, touch_monitor_prefix, NULL, ast_free);
 150
 151         set_touch_res = set_touch_variables(bridge_channel->chan, 0, &touch_format,
 152                 &touch_monitor, &touch_monitor_prefix);
 153         switch (set_touch_res) {
 154         case SET_TOUCH_SUCCESS:
 155                 break;
 156         case SET_TOUCH_UNSET:
 157                 set_touch_res = set_touch_variables(peer_chan, 0, &touch_format, &touch_monitor,
 158                         &touch_monitor_prefix);
 159                 if (set_touch_res == SET_TOUCH_ALLOC_FAILURE) {
 160                         return;
 161                 }
 162                 break;
 163         case SET_TOUCH_ALLOC_FAILURE:
 164                 return;
 165         }
 166
 167         if (!ast_strlen_zero(touch_monitor)) {
 168                 len = strlen(touch_monitor) + 50;
 169                 touch_filename = ast_alloca(len);
 170                 snprintf(touch_filename, len, "%s-%ld-%s",
 171                         S_OR(touch_monitor_prefix, "auto"),
 172                         (long) time(NULL),
 173                         touch_monitor);
 174         } else {
 175                 char *caller_chan_id;
 176                 char *peer_chan_id;
 177
 178                 caller_chan_id = ast_strdupa(S_COR(ast_channel_caller(bridge_channel->chan)->id.number.valid,
 179                         ast_channel_caller(bridge_channel->chan)->id.number.str, ast_channel_name(bridge_channel->chan)));
 180                 peer_chan_id = ast_strdupa(S_COR(ast_channel_caller(peer_chan)->id.number.valid,
 181                         ast_channel_caller(peer_chan)->id.number.str, ast_channel_name(peer_chan)));
 182                 len = strlen(caller_chan_id) + strlen(peer_chan_id) + 50;
 183                 touch_filename = ast_alloca(len);
 184                 snprintf(touch_filename, len, "%s-%ld-%s-%s",
 185                         S_OR(touch_monitor_prefix, "auto"),
 186                         (long) time(NULL),
 187                         caller_chan_id,
 188                         peer_chan_id);
 189         }
 190
 191         for (x = 0; x < strlen(touch_filename); x++) {
 192                 if (touch_filename[x] == '/') {
 193                         touch_filename[x] = '-';
 194                 }
 195         }
 196
 197         ast_verb(4, "AutoMonitor used to record call. Filename: %s\n", touch_filename);
 198
 199         if (ast_monitor_start(peer_chan, touch_format, touch_filename, 1, X_REC_IN | X_REC_OUT, NULL)) {
 200                 ast_verb(4, "AutoMonitor feature was tried by '%s' but monitor failed to start.\n",
 201                         ast_channel_name(bridge_channel->chan));
 202                 return;
 203         }
 204
 205         if (features_cfg && !ast_strlen_zero(features_cfg->courtesytone)) {
 206                 ast_bridge_channel_queue_playfile(bridge_channel, NULL, features_cfg->courtesytone, NULL);
 207                 ast_bridge_channel_write_playfile(bridge_channel, NULL, features_cfg->courtesytone, NULL);
 208         }
 209
 210         if (!ast_strlen_zero(start_message)) {
 211                 ast_bridge_channel_queue_playfile(bridge_channel, NULL, start_message, NULL);
 212                 ast_bridge_channel_write_playfile(bridge_channel, NULL, start_message, NULL);
 213         }
 214
 215         pbx_builtin_setvar_helper(peer_chan, "TOUCH_MONITOR_OUTPUT", touch_filename);
 216 }
 217
 218 static int feature_automonitor(struct ast_bridge_channel *bridge_channel, void *hook_pvt)
 219 {
 220         const char *start_message;
 221         const char *stop_message;
 222         struct ast_bridge_features_automonitor *options = hook_pvt;
 223         enum ast_bridge_features_monitor start_stop = options ? options->start_stop : AUTO_MONITOR_TOGGLE;
 224         int is_monitoring;
 225
 226         RAII_VAR(struct ast_channel *, peer_chan, NULL, ast_channel_cleanup);
 227         RAII_VAR(struct ast_features_general_config *, features_cfg, NULL, ao2_cleanup);
 228
 229         ast_channel_lock(bridge_channel->chan);
 230         features_cfg = ast_get_chan_features_general_config(bridge_channel->chan);
 231         ast_channel_unlock(bridge_channel->chan);
 232         ast_bridge_channel_lock_bridge(bridge_channel);
 233         peer_chan = ast_bridge_peer_nolock(bridge_channel->bridge, bridge_channel->chan);
 234         ast_bridge_unlock(bridge_channel->bridge);
 235
 236         if (!peer_chan) {
 237                 ast_verb(4, "Cannot start AutoMonitor for %s - can not determine peer in bridge.\n",
 238                         ast_channel_name(bridge_channel->chan));
 239                 if (features_cfg && !ast_strlen_zero(features_cfg->recordingfailsound)) {
 240                         ast_bridge_channel_queue_playfile(bridge_channel, NULL, features_cfg->recordingfailsound, NULL);
 241                 }
 242                 return 0;
 243         }
 244
 245         ast_channel_lock(bridge_channel->chan);
 246         start_message = pbx_builtin_getvar_helper(bridge_channel->chan,
 247                 "TOUCH_MONITOR_MESSAGE_START");
 248         start_message = ast_strdupa(S_OR(start_message, ""));
 249         stop_message = pbx_builtin_getvar_helper(bridge_channel->chan,
 250                 "TOUCH_MONITOR_MESSAGE_STOP");
 251         stop_message = ast_strdupa(S_OR(stop_message, ""));
 252         ast_channel_unlock(bridge_channel->chan);
 253
 254         is_monitoring = ast_channel_monitor(peer_chan) != NULL;
 255         switch (start_stop) {
 256         case AUTO_MONITOR_TOGGLE:
 257                 if (is_monitoring) {
 258                         stop_automonitor(bridge_channel, peer_chan, features_cfg, stop_message);
 259                 } else {
 260                         start_automonitor(bridge_channel, peer_chan, features_cfg, start_message);
 261                 }
 262                 return 0;
 263         case AUTO_MONITOR_START:
 264                 if (!is_monitoring) {
 265                         start_automonitor(bridge_channel, peer_chan, features_cfg, start_message);
 266                         return 0;
 267                 }
 268                 ast_verb(4, "AutoMonitor already recording call.\n");
 269                 break;
 270         case AUTO_MONITOR_STOP:
 271                 if (is_monitoring) {
 272                         stop_automonitor(bridge_channel, peer_chan, features_cfg, stop_message);
 273                         return 0;
 274                 }
 275                 ast_verb(4, "AutoMonitor already stopped on call.\n");
 276                 break;
 277         }
 278
 279         /*
 280          * Fake start/stop to invoker so will think it did something but
 281          * was already in that mode.
 282          */
 283         if (features_cfg && !ast_strlen_zero(features_cfg->courtesytone)) {
 284                 ast_bridge_channel_queue_playfile(bridge_channel, NULL, features_cfg->courtesytone, NULL);
 285         }
 286         if (is_monitoring) {
 287                 if (!ast_strlen_zero(start_message)) {
 288                         ast_bridge_channel_queue_playfile(bridge_channel, NULL, start_message, NULL);
 289                 }
 290         } else {
 291                 if (!ast_strlen_zero(stop_message)) {
 292                         ast_bridge_channel_queue_playfile(bridge_channel, NULL, stop_message, NULL);
 293                 }
 294         }
 295         return 0;
 296 }
 297
 298 static void stop_automixmonitor(struct ast_bridge_channel *bridge_channel, struct ast_channel *peer_chan, struct ast_features_general_config *features_cfg, const char *stop_message)
 299 {
 300         ast_verb(4, "AutoMixMonitor used to stop recording call.\n");
 301
 302         if (ast_stop_mixmonitor(peer_chan, NULL)) {
 303                 ast_verb(4, "Failed to stop AutoMixMonitor for %s.\n", ast_channel_name(bridge_channel->chan));
 304                 if (features_cfg && !(ast_strlen_zero(features_cfg->recordingfailsound))) {
 305                         ast_bridge_channel_queue_playfile(bridge_channel, NULL, features_cfg->recordingfailsound, NULL);
 306                 }
 307                 return;
 308         }
 309
 310         if (features_cfg && !ast_strlen_zero(features_cfg->courtesytone)) {
 311                 ast_bridge_channel_queue_playfile(bridge_channel, NULL, features_cfg->courtesytone, NULL);
 312                 ast_bridge_channel_write_playfile(bridge_channel, NULL, features_cfg->courtesytone, NULL);
 313         }
 314
 315         if (!ast_strlen_zero(stop_message)) {
 316                 ast_bridge_channel_queue_playfile(bridge_channel, NULL, stop_message, NULL);
 317                 ast_bridge_channel_write_playfile(bridge_channel, NULL, stop_message, NULL);
 318         }
 319 }
 320
 321 static void start_automixmonitor(struct ast_bridge_channel *bridge_channel, struct ast_channel *peer_chan, struct ast_features_general_config *features_cfg, const char *start_message)
 322 {
 323         char *touch_filename;
 324         size_t len;
 325         int x;
 326         enum set_touch_variables_res set_touch_res;
 327
 328         RAII_VAR(char *, touch_format, NULL, ast_free);
 329         RAII_VAR(char *, touch_monitor, NULL, ast_free);
 330         RAII_VAR(char *, touch_monitor_prefix, NULL, ast_free);
 331
 332         set_touch_res = set_touch_variables(bridge_channel->chan, 1, &touch_format,
 333                 &touch_monitor, &touch_monitor_prefix);
 334         switch (set_touch_res) {
 335         case SET_TOUCH_SUCCESS:
 336                 break;
 337         case SET_TOUCH_UNSET:
 338                 set_touch_res = set_touch_variables(peer_chan, 1, &touch_format, &touch_monitor,
 339                         &touch_monitor_prefix);
 340                 if (set_touch_res == SET_TOUCH_ALLOC_FAILURE) {
 341                         return;
 342                 }
 343                 break;
 344         case SET_TOUCH_ALLOC_FAILURE:
 345                 return;
 346         }
 347
 348         if (!ast_strlen_zero(touch_monitor)) {
 349                 len = strlen(touch_monitor) + 50;
 350                 touch_filename = ast_alloca(len);
 351                 snprintf(touch_filename, len, "%s-%ld-%s.%s",
 352                         S_OR(touch_monitor_prefix, "auto"),
 353                         (long) time(NULL),
 354                         touch_monitor,
 355                         S_OR(touch_format, "wav"));
 356         } else {
 357                 char *caller_chan_id;
 358                 char *peer_chan_id;
 359
 360                 caller_chan_id = ast_strdupa(S_COR(ast_channel_caller(bridge_channel->chan)->id.number.valid,
 361                         ast_channel_caller(bridge_channel->chan)->id.number.str, ast_channel_name(bridge_channel->chan)));
 362                 peer_chan_id = ast_strdupa(S_COR(ast_channel_caller(peer_chan)->id.number.valid,
 363                         ast_channel_caller(peer_chan)->id.number.str, ast_channel_name(peer_chan)));
 364                 len = strlen(caller_chan_id) + strlen(peer_chan_id) + 50;
 365                 touch_filename = ast_alloca(len);
 366                 snprintf(touch_filename, len, "%s-%ld-%s-%s.%s",
 367                         S_OR(touch_monitor_prefix, "auto"),
 368                         (long) time(NULL),
 369                         caller_chan_id,
 370                         peer_chan_id,
 371                         S_OR(touch_format, "wav"));
 372         }
 373
 374         for (x = 0; x < strlen(touch_filename); x++) {
 375                 if (touch_filename[x] == '/') {
 376                         touch_filename[x] = '-';
 377                 }
 378         }
 379
 380         ast_verb(4, "AutoMixMonitor used to record call. Filename: %s\n", touch_filename);
 381
 382         if (ast_start_mixmonitor(peer_chan, touch_filename, "b")) {
 383                 ast_verb(4, "AutoMixMonitor feature was tried by '%s' but MixMonitor failed to start.\n",
 384                         ast_channel_name(bridge_channel->chan));
 385
 386                 if (features_cfg && !ast_strlen_zero(features_cfg->recordingfailsound)) {
 387                         ast_bridge_channel_queue_playfile(bridge_channel, NULL, features_cfg->recordingfailsound, NULL);
 388                 }
 389                 return;
 390         }
 391
 392         if (features_cfg && !ast_strlen_zero(features_cfg->courtesytone)) {
 393                 ast_bridge_channel_queue_playfile(bridge_channel, NULL, features_cfg->courtesytone, NULL);
 394                 ast_bridge_channel_write_playfile(bridge_channel, NULL, features_cfg->courtesytone, NULL);
 395         }
 396
 397         if (!ast_strlen_zero(start_message)) {
 398                 ast_bridge_channel_queue_playfile(bridge_channel, NULL, start_message, NULL);
 399                 ast_bridge_channel_write_playfile(bridge_channel, NULL, start_message, NULL);
 400         }
 401
 402         pbx_builtin_setvar_helper(peer_chan, "TOUCH_MIXMONITOR_OUTPUT", touch_filename);
 403 }
 404
 405 static int feature_automixmonitor(struct ast_bridge_channel *bridge_channel, void *hook_pvt)
 406 {
 407         static const char *mixmonitor_spy_type = "MixMonitor";
 408         const char *stop_message;
 409         const char *start_message;
 410         struct ast_bridge_features_automixmonitor *options = hook_pvt;
 411         enum ast_bridge_features_monitor start_stop = options ? options->start_stop : AUTO_MONITOR_TOGGLE;
 412         int is_monitoring;
 413
 414         RAII_VAR(struct ast_channel *, peer_chan, NULL, ast_channel_cleanup);
 415         RAII_VAR(struct ast_features_general_config *, features_cfg, NULL, ao2_cleanup);
 416
 417         ast_channel_lock(bridge_channel->chan);
 418         features_cfg = ast_get_chan_features_general_config(bridge_channel->chan);
 419         ast_channel_unlock(bridge_channel->chan);
 420         ast_bridge_channel_lock_bridge(bridge_channel);
 421         peer_chan = ast_bridge_peer_nolock(bridge_channel->bridge, bridge_channel->chan);
 422         ast_bridge_unlock(bridge_channel->bridge);
 423
 424         if (!peer_chan) {
 425                 ast_verb(4, "Cannot start AutoMixMonitor for %s - cannot determine peer in bridge.\n",
 426                         ast_channel_name(bridge_channel->chan));
 427                 if (features_cfg && !ast_strlen_zero(features_cfg->recordingfailsound)) {
 428                         ast_bridge_channel_queue_playfile(bridge_channel, NULL, features_cfg->recordingfailsound, NULL);
 429                 }
 430                 return 0;
 431         }
 432
 433         ast_channel_lock(bridge_channel->chan);
 434         start_message = pbx_builtin_getvar_helper(bridge_channel->chan,
 435                 "TOUCH_MIXMONITOR_MESSAGE_START");
 436         start_message = ast_strdupa(S_OR(start_message, ""));
 437         stop_message = pbx_builtin_getvar_helper(bridge_channel->chan,
 438                 "TOUCH_MIXMONITOR_MESSAGE_STOP");
 439         stop_message = ast_strdupa(S_OR(stop_message, ""));
 440         ast_channel_unlock(bridge_channel->chan);
 441
 442         is_monitoring =
 443                 0 < ast_channel_audiohook_count_by_source(peer_chan, mixmonitor_spy_type, AST_AUDIOHOOK_TYPE_SPY);
 444         switch (start_stop) {
 445         case AUTO_MONITOR_TOGGLE:
 446                 if (is_monitoring) {
 447                         stop_automixmonitor(bridge_channel, peer_chan, features_cfg, stop_message);
 448                 } else {
 449                         start_automixmonitor(bridge_channel, peer_chan, features_cfg, start_message);
 450                 }
 451                 return 0;
 452         case AUTO_MONITOR_START:
 453                 if (!is_monitoring) {
 454                         start_automixmonitor(bridge_channel, peer_chan, features_cfg, start_message);
 455                         return 0;
 456                 }
 457                 ast_verb(4, "AutoMixMonitor already recording call.\n");
 458                 break;
 459         case AUTO_MONITOR_STOP:
 460                 if (is_monitoring) {
 461                         stop_automixmonitor(bridge_channel, peer_chan, features_cfg, stop_message);
 462                         return 0;
 463                 }
 464                 ast_verb(4, "AutoMixMonitor already stopped on call.\n");
 465                 break;
 466         }
 467
 468         /*
 469          * Fake start/stop to invoker so will think it did something but
 470          * was already in that mode.
 471          */
 472         if (features_cfg && !ast_strlen_zero(features_cfg->courtesytone)) {
 473                 ast_bridge_channel_queue_playfile(bridge_channel, NULL, features_cfg->courtesytone, NULL);
 474         }
 475         if (is_monitoring) {
 476                 if (!ast_strlen_zero(start_message)) {
 477                         ast_bridge_channel_queue_playfile(bridge_channel, NULL, start_message, NULL);
 478                 }
 479         } else {
 480                 if (!ast_strlen_zero(stop_message)) {
 481                         ast_bridge_channel_queue_playfile(bridge_channel, NULL, stop_message, NULL);
 482                 }
 483         }
 484         return 0;
 485 }
 486
 487 /*! \brief Internal built in feature for hangup */
 488 static int feature_hangup(struct ast_bridge_channel *bridge_channel, void *hook_pvt)
 489 {
 490         /*
 491          * This is very simple, we simply change the state on the
 492          * bridge_channel to force the channel out of the bridge and the
 493          * core takes care of the rest.
 494          */
 495         ast_bridge_channel_leave_bridge(bridge_channel, BRIDGE_CHANNEL_STATE_END,
 496                 AST_CAUSE_NORMAL_CLEARING);
 497         return 0;
 498 }
 499
 500 static int unload_module(void)
 501 {
 502         ast_bridge_features_unregister(AST_BRIDGE_BUILTIN_HANGUP);
 503         ast_bridge_features_unregister(AST_BRIDGE_BUILTIN_AUTOMON);
 504         ast_bridge_features_unregister(AST_BRIDGE_BUILTIN_AUTOMIXMON);
 505
 506         return 0;
 507 }
 508
 509 static int load_module(void)
 510 {
 511         ast_bridge_features_register(AST_BRIDGE_BUILTIN_HANGUP, feature_hangup, NULL);
 512         ast_bridge_features_register(AST_BRIDGE_BUILTIN_AUTOMON, feature_automonitor, NULL);
 513         ast_bridge_features_register(AST_BRIDGE_BUILTIN_AUTOMIXMON, feature_automixmonitor, NULL);
 514
 515         /* This module cannot be unloaded until shutdown */
 516         ast_module_shutdown_ref(ast_module_info->self);
 517
 518         return AST_MODULE_LOAD_SUCCESS;
 519 }
 520
 521 AST_MODULE_INFO_STANDARD(ASTERISK_GPL_KEY, "Built in bridging features");