channels/chan_features.c

   1 /*
   2  * Asterisk -- An open source telephony toolkit.
   3  *
   4  * Copyright (C) 1999 - 2005, Digium, Inc.
   5  *
   6  * Mark Spencer <markster@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 feature Proxy Channel
  22  *
  23  * \author Mark Spencer <markster@digium.com>
  24  *
  25  * \note *** Experimental code ****
  26  *
  27  * \ingroup channel_drivers
  28  */
  29 /*** MODULEINFO
  30         <defaultenabled>no</defaultenabled>
  31  ***/
  32
  33 #include "asterisk.h"
  34
  35 ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
  36
  37 #include <fcntl.h>
  38 #include <sys/signal.h>
  39
  40 #include "asterisk/lock.h"
  41 #include "asterisk/channel.h"
  42 #include "asterisk/config.h"
  43 #include "asterisk/module.h"
  44 #include "asterisk/pbx.h"
  45 #include "asterisk/sched.h"
  46 #include "asterisk/io.h"
  47 #include "asterisk/rtp.h"
  48 #include "asterisk/acl.h"
  49 #include "asterisk/callerid.h"
  50 #include "asterisk/file.h"
  51 #include "asterisk/cli.h"
  52 #include "asterisk/app.h"
  53 #include "asterisk/musiconhold.h"
  54 #include "asterisk/manager.h"
  55 #include "asterisk/stringfields.h"
  56
  57 static const char tdesc[] = "Feature Proxy Channel Driver";
  58
  59 #define IS_OUTBOUND(a,b) (a == b->chan ? 1 : 0)
  60
  61 struct feature_sub {
  62         struct ast_channel *owner;
  63         int inthreeway;
  64         int pfd;
  65         int timingfdbackup;
  66         int alertpipebackup[2];
  67 };
  68
  69 struct feature_pvt {
  70         ast_mutex_t lock;                       /* Channel private lock */
  71         char tech[AST_MAX_EXTENSION];           /* Technology to abstract */
  72         char dest[AST_MAX_EXTENSION];           /* Destination to abstract */
  73         struct ast_channel *subchan;
  74         struct feature_sub subs[3];             /* Subs */
  75         struct ast_channel *owner;              /* Current Master Channel */
  76         AST_LIST_ENTRY(feature_pvt) list;       /* Next entity */
  77 };
  78
  79 static AST_LIST_HEAD_STATIC(features, feature_pvt);
  80
  81 #define SUB_REAL        0                       /* Active call */
  82 #define SUB_CALLWAIT    1                       /* Call-Waiting call on hold */
  83 #define SUB_THREEWAY    2                       /* Three-way call */
  84
  85 static struct ast_channel *features_request(const char *type, int format, void *data, int *cause);
  86 static int features_digit_begin(struct ast_channel *ast, char digit);
  87 static int features_digit_end(struct ast_channel *ast, char digit, unsigned int duration);
  88 static int features_call(struct ast_channel *ast, char *dest, int timeout);
  89 static int features_hangup(struct ast_channel *ast);
  90 static int features_answer(struct ast_channel *ast);
  91 static struct ast_frame *features_read(struct ast_channel *ast);
  92 static int features_write(struct ast_channel *ast, struct ast_frame *f);
  93 static int features_indicate(struct ast_channel *ast, int condition, const void *data, size_t datalen);
  94 static int features_fixup(struct ast_channel *oldchan, struct ast_channel *newchan);
  95
  96 static const struct ast_channel_tech features_tech = {
  97         .type = "Feature",
  98         .description = tdesc,
  99         .capabilities = -1,
 100         .requester = features_request,
 101         .send_digit_begin = features_digit_begin,
 102         .send_digit_end = features_digit_end,
 103         .call = features_call,
 104         .hangup = features_hangup,
 105         .answer = features_answer,
 106         .read = features_read,
 107         .write = features_write,
 108         .exception = features_read,
 109         .indicate = features_indicate,
 110         .fixup = features_fixup,
 111 };
 112
 113 static inline void init_sub(struct feature_sub *sub)
 114 {
 115         sub->inthreeway = 0;
 116         sub->pfd = -1;
 117         sub->timingfdbackup = -1;
 118         sub->alertpipebackup[0] = sub->alertpipebackup[1] = -1;
 119 }
 120
 121 static inline int indexof(struct feature_pvt *p, struct ast_channel *owner, int nullok)
 122 {
 123         int x;
 124         if (!owner) {
 125                 ast_log(LOG_WARNING, "indexof called on NULL owner??\n");
 126                 return -1;
 127         }
 128         for (x=0; x<3; x++) {
 129                 if (owner == p->subs[x].owner)
 130                         return x;
 131         }
 132         return -1;
 133 }
 134
 135 #if 0
 136 static void wakeup_sub(struct feature_pvt *p, int a)
 137 {
 138         struct ast_frame null = { AST_FRAME_NULL, };
 139         for (;;) {
 140                 if (p->subs[a].owner) {
 141                         if (ast_mutex_trylock(&p->subs[a].owner->lock)) {
 142                                 ast_mutex_unlock(&p->lock);
 143                                 usleep(1);
 144                                 ast_mutex_lock(&p->lock);
 145                         } else {
 146                                 ast_queue_frame(p->subs[a].owner, &null);
 147                                 ast_mutex_unlock(&p->subs[a].owner->lock);
 148                                 break;
 149                         }
 150                 } else
 151                         break;
 152         }
 153 }
 154 #endif
 155
 156 static void restore_channel(struct feature_pvt *p, int index)
 157 {
 158         /* Restore timing/alertpipe */
 159         p->subs[index].owner->timingfd = p->subs[index].timingfdbackup;
 160         p->subs[index].owner->alertpipe[0] = p->subs[index].alertpipebackup[0];
 161         p->subs[index].owner->alertpipe[1] = p->subs[index].alertpipebackup[1];
 162         ast_channel_set_fd(p->subs[index].owner, AST_ALERT_FD, p->subs[index].alertpipebackup[0]);
 163         ast_channel_set_fd(p->subs[index].owner, AST_TIMING_FD, p->subs[index].timingfdbackup);
 164 }
 165
 166 static void update_features(struct feature_pvt *p, int index)
 167 {
 168         int x;
 169         if (p->subs[index].owner) {
 170                 for (x=0; x<AST_MAX_FDS; x++) {
 171                         if (index)
 172                                 ast_channel_set_fd(p->subs[index].owner, x, -1);
 173                         else
 174                                 ast_channel_set_fd(p->subs[index].owner, x, p->subchan->fds[x]);
 175                 }
 176                 if (!index) {
 177                         /* Copy timings from master channel */
 178                         p->subs[index].owner->timingfd = p->subchan->timingfd;
 179                         p->subs[index].owner->alertpipe[0] = p->subchan->alertpipe[0];
 180                         p->subs[index].owner->alertpipe[1] = p->subchan->alertpipe[1];
 181                         if (p->subs[index].owner->nativeformats != p->subchan->readformat) {
 182                                 p->subs[index].owner->nativeformats = p->subchan->readformat;
 183                                 if (p->subs[index].owner->readformat)
 184                                         ast_set_read_format(p->subs[index].owner, p->subs[index].owner->readformat);
 185                                 if (p->subs[index].owner->writeformat)
 186                                         ast_set_write_format(p->subs[index].owner, p->subs[index].owner->writeformat);
 187                         }
 188                 } else{
 189                         restore_channel(p, index);
 190                 }
 191         }
 192 }
 193
 194 #if 0
 195 static void swap_subs(struct feature_pvt *p, int a, int b)
 196 {
 197         int tinthreeway;
 198         struct ast_channel *towner;
 199
 200         ast_debug(1, "Swapping %d and %d\n", a, b);
 201
 202         towner = p->subs[a].owner;
 203         tinthreeway = p->subs[a].inthreeway;
 204
 205         p->subs[a].owner = p->subs[b].owner;
 206         p->subs[a].inthreeway = p->subs[b].inthreeway;
 207
 208         p->subs[b].owner = towner;
 209         p->subs[b].inthreeway = tinthreeway;
 210         update_features(p,a);
 211         update_features(p,b);
 212         wakeup_sub(p, a);
 213         wakeup_sub(p, b);
 214 }
 215 #endif
 216
 217 static int features_answer(struct ast_channel *ast)
 218 {
 219         struct feature_pvt *p = ast->tech_pvt;
 220         int res = -1;
 221         int x;
 222
 223         ast_mutex_lock(&p->lock);
 224         x = indexof(p, ast, 0);
 225         if (!x && p->subchan)
 226                 res = ast_answer(p->subchan);
 227         ast_mutex_unlock(&p->lock);
 228         return res;
 229 }
 230
 231 static struct ast_frame  *features_read(struct ast_channel *ast)
 232 {
 233         struct feature_pvt *p = ast->tech_pvt;
 234         struct ast_frame *f;
 235         int x;
 236
 237         f = &ast_null_frame;
 238         ast_mutex_lock(&p->lock);
 239         x = indexof(p, ast, 0);
 240         if (!x && p->subchan) {
 241                 update_features(p, x);
 242                 f = ast_read(p->subchan);
 243         }
 244         ast_mutex_unlock(&p->lock);
 245         return f;
 246 }
 247
 248 static int features_write(struct ast_channel *ast, struct ast_frame *f)
 249 {
 250         struct feature_pvt *p = ast->tech_pvt;
 251         int res = -1;
 252         int x;
 253
 254         ast_mutex_lock(&p->lock);
 255         x = indexof(p, ast, 0);
 256         if (!x && p->subchan)
 257                 res = ast_write(p->subchan, f);
 258         ast_mutex_unlock(&p->lock);
 259         return res;
 260 }
 261
 262 static int features_fixup(struct ast_channel *oldchan, struct ast_channel *newchan)
 263 {
 264         struct feature_pvt *p = newchan->tech_pvt;
 265         int x;
 266
 267         ast_mutex_lock(&p->lock);
 268         if (p->owner == oldchan)
 269                 p->owner = newchan;
 270         for (x = 0; x < 3; x++) {
 271                 if (p->subs[x].owner == oldchan)
 272                         p->subs[x].owner = newchan;
 273         }
 274         ast_mutex_unlock(&p->lock);
 275         return 0;
 276 }
 277
 278 static int features_indicate(struct ast_channel *ast, int condition, const void *data, size_t datalen)
 279 {
 280         struct feature_pvt *p = ast->tech_pvt;
 281         int res = -1;
 282         int x;
 283
 284         /* Queue up a frame representing the indication as a control frame */
 285         ast_mutex_lock(&p->lock);
 286         x = indexof(p, ast, 0);
 287         if (!x && p->subchan)
 288                 res = ast_indicate(p->subchan, condition);
 289         ast_mutex_unlock(&p->lock);
 290         return res;
 291 }
 292
 293 static int features_digit_begin(struct ast_channel *ast, char digit)
 294 {
 295         struct feature_pvt *p = ast->tech_pvt;
 296         int res = -1;
 297         int x;
 298
 299         /* Queue up a frame representing the indication as a control frame */
 300         ast_mutex_lock(&p->lock);
 301         x = indexof(p, ast, 0);
 302         if (!x && p->subchan)
 303                 res = ast_senddigit_begin(p->subchan, digit);
 304         ast_mutex_unlock(&p->lock);
 305
 306         return res;
 307 }
 308
 309 static int features_digit_end(struct ast_channel *ast, char digit, unsigned int duration)
 310 {
 311         struct feature_pvt *p = ast->tech_pvt;
 312         int res = -1;
 313         int x;
 314
 315         /* Queue up a frame representing the indication as a control frame */
 316         ast_mutex_lock(&p->lock);
 317         x = indexof(p, ast, 0);
 318         if (!x && p->subchan)
 319                 res = ast_senddigit_end(p->subchan, digit, duration);
 320         ast_mutex_unlock(&p->lock);
 321         return res;
 322 }
 323
 324 static int features_call(struct ast_channel *ast, char *dest, int timeout)
 325 {
 326         struct feature_pvt *p = ast->tech_pvt;
 327         int res = -1;
 328         int x;
 329         char *dest2;
 330
 331         dest2 = strchr(dest, '/');
 332         if (dest2) {
 333                 ast_mutex_lock(&p->lock);
 334                 x = indexof(p, ast, 0);
 335                 if (!x && p->subchan) {
 336                         p->subchan->cid.cid_num = ast_strdup(p->owner->cid.cid_num);
 337                         p->subchan->cid.cid_name = ast_strdup(p->owner->cid.cid_name);
 338                         p->subchan->cid.cid_rdnis = ast_strdup(p->owner->cid.cid_rdnis);
 339                         p->subchan->cid.cid_ani = ast_strdup(p->owner->cid.cid_ani);
 340
 341                         p->subchan->cid.cid_pres = p->owner->cid.cid_pres;
 342                         ast_string_field_set(p->subchan, language, p->owner->language);
 343                         ast_string_field_set(p->subchan, accountcode, p->owner->accountcode);
 344                         p->subchan->cdrflags = p->owner->cdrflags;
 345                         res = ast_call(p->subchan, dest2, timeout);
 346                         update_features(p, x);
 347                 } else
 348                         ast_log(LOG_NOTICE, "Uhm yah, not quite there with the call waiting...\n");
 349                 ast_mutex_unlock(&p->lock);
 350         }
 351         return res;
 352 }
 353
 354 static int features_hangup(struct ast_channel *ast)
 355 {
 356         struct feature_pvt *p = ast->tech_pvt;
 357         int x;
 358
 359         ast_mutex_lock(&p->lock);
 360         x = indexof(p, ast, 0);
 361         if (x > -1) {
 362                 restore_channel(p, x);
 363                 p->subs[x].owner = NULL;
 364                 /* XXX Re-arrange, unconference, etc XXX */
 365         }
 366         ast->tech_pvt = NULL;
 367
 368         if (!p->subs[SUB_REAL].owner && !p->subs[SUB_CALLWAIT].owner && !p->subs[SUB_THREEWAY].owner) {
 369                 ast_mutex_unlock(&p->lock);
 370                 /* Remove from list */
 371                 AST_LIST_LOCK(&features);
 372                 AST_LIST_REMOVE(&features, p, list);
 373                 AST_LIST_UNLOCK(&features);
 374                 ast_mutex_lock(&p->lock);
 375                 /* And destroy */
 376                 if (p->subchan)
 377                         ast_hangup(p->subchan);
 378                 ast_mutex_unlock(&p->lock);
 379                 ast_mutex_destroy(&p->lock);
 380                 ast_free(p);
 381                 return 0;
 382         }
 383         ast_mutex_unlock(&p->lock);
 384         return 0;
 385 }
 386
 387 static struct feature_pvt *features_alloc(char *data, int format)
 388 {
 389         struct feature_pvt *tmp;
 390         char *dest=NULL;
 391         char *tech;
 392         int x;
 393         int status;
 394         struct ast_channel *chan;
 395
 396         tech = ast_strdupa(data);
 397         if (tech) {
 398                 dest = strchr(tech, '/');
 399                 if (dest) {
 400                         *dest = '\0';
 401                         dest++;
 402                 }
 403         }
 404         if (!tech || !dest) {
 405                 ast_log(LOG_NOTICE, "Format for feature channel is Feature/Tech/Dest ('%s' not valid)!\n",
 406                         data);
 407                 return NULL;
 408         }
 409         AST_LIST_LOCK(&features);
 410         AST_LIST_TRAVERSE(&features, tmp, list) {
 411                 if (!strcasecmp(tmp->tech, tech) && !strcmp(tmp->dest, dest))
 412                         break;
 413         }
 414         AST_LIST_UNLOCK(&features);
 415         if (!tmp) {
 416                 chan = ast_request(tech, format, dest, &status);
 417                 if (!chan) {
 418                         ast_log(LOG_NOTICE, "Unable to allocate subchannel '%s/%s'\n", tech, dest);
 419                         return NULL;
 420                 }
 421                 tmp = ast_calloc(1, sizeof(*tmp));
 422                 if (tmp) {
 423                         for (x=0;x<3;x++)
 424                                 init_sub(tmp->subs + x);
 425                         ast_mutex_init(&tmp->lock);
 426                         ast_copy_string(tmp->tech, tech, sizeof(tmp->tech));
 427                         ast_copy_string(tmp->dest, dest, sizeof(tmp->dest));
 428                         tmp->subchan = chan;
 429                         AST_LIST_LOCK(&features);
 430                         AST_LIST_INSERT_HEAD(&features, tmp, list);
 431                         AST_LIST_UNLOCK(&features);
 432                 }
 433         }
 434         return tmp;
 435 }
 436
 437 static struct ast_channel *features_new(struct feature_pvt *p, int state, int index)
 438 {
 439         struct ast_channel *tmp;
 440         int x,y;
 441         char *b2 = 0;
 442         if (!p->subchan) {
 443                 ast_log(LOG_WARNING, "Called upon channel with no subchan:(\n");
 444                 return NULL;
 445         }
 446         if (p->subs[index].owner) {
 447                 ast_log(LOG_WARNING, "Called to put index %d already there!\n", index);
 448                 return NULL;
 449         }
 450         /* figure out what you want the name to be */
 451         for (x=1;x<4;x++) {
 452                 if (b2)
 453                         ast_free(b2);
 454                 asprintf(&b2, "%s/%s-%d", p->tech, p->dest, x);
 455                 for (y=0;y<3;y++) {
 456                         if (y == index)
 457                                 continue;
 458                         if (p->subs[y].owner && !strcasecmp(p->subs[y].owner->name, b2))
 459                                 break;
 460                 }
 461                 if (y >= 3)
 462                         break;
 463         }
 464         tmp = ast_channel_alloc(0, state, 0,0, "", "", "", 0, "Feature/%s", b2);
 465         /* free up the name, it was copied into the channel name */
 466         if (b2)
 467                 ast_free(b2);
 468         if (!tmp) {
 469                 ast_log(LOG_WARNING, "Unable to allocate channel structure\n");
 470                 return NULL;
 471         }
 472         tmp->tech = &features_tech;
 473         tmp->writeformat = p->subchan->writeformat;
 474         tmp->rawwriteformat = p->subchan->rawwriteformat;
 475         tmp->readformat = p->subchan->readformat;
 476         tmp->rawreadformat = p->subchan->rawreadformat;
 477         tmp->nativeformats = p->subchan->readformat;
 478         tmp->tech_pvt = p;
 479         p->subs[index].owner = tmp;
 480         if (!p->owner)
 481                 p->owner = tmp;
 482         ast_module_ref(ast_module_info->self);
 483         return tmp;
 484 }
 485
 486
 487 static struct ast_channel *features_request(const char *type, int format, void *data, int *cause)
 488 {
 489         struct feature_pvt *p;
 490         struct ast_channel *chan = NULL;
 491
 492         p = features_alloc(data, format);
 493         if (p && !p->subs[SUB_REAL].owner)
 494                 chan = features_new(p, AST_STATE_DOWN, SUB_REAL);
 495         if (chan)
 496                 update_features(p,SUB_REAL);
 497         return chan;
 498 }
 499
 500 static char *features_show(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
 501 {
 502         struct feature_pvt *p;
 503
 504         switch (cmd) {
 505         case CLI_INIT:
 506                 e->command = "feature show channels";
 507                 e->usage =
 508                         "Usage: feature show channels\n"
 509                         "       Provides summary information on feature channels.\n";
 510                 return NULL;
 511         case CLI_GENERATE:
 512                 return NULL;
 513         }
 514
 515         if (a->argc != 3)
 516                 return CLI_SHOWUSAGE;
 517
 518         if (AST_LIST_EMPTY(&features)) {
 519                 ast_cli(a->fd, "No feature channels in use\n");
 520                 return CLI_SUCCESS;
 521         }
 522
 523         AST_LIST_LOCK(&features);
 524         AST_LIST_TRAVERSE(&features, p, list) {
 525                 ast_mutex_lock(&p->lock);
 526                 ast_cli(a->fd, "%s -- %s/%s\n", p->owner ? p->owner->name : "<unowned>", p->tech, p->dest);
 527                 ast_mutex_unlock(&p->lock);
 528         }
 529         AST_LIST_UNLOCK(&features);
 530         return CLI_SUCCESS;
 531 }
 532
 533 static struct ast_cli_entry cli_features[] = {
 534         AST_CLI_DEFINE(features_show, "List status of feature channels"),
 535 };
 536
 537 static int load_module(void)
 538 {
 539         /* Make sure we can register our sip channel type */
 540         if (ast_channel_register(&features_tech)) {
 541                 ast_log(LOG_ERROR, "Unable to register channel class 'Feature'\n");
 542                 return AST_MODULE_LOAD_FAILURE;
 543         }
 544         ast_cli_register_multiple(cli_features, sizeof(cli_features) / sizeof(struct ast_cli_entry));
 545         return AST_MODULE_LOAD_SUCCESS;
 546 }
 547
 548 static int unload_module(void)
 549 {
 550         struct feature_pvt *p;
 551
 552         /* First, take us out of the channel loop */
 553         ast_cli_unregister_multiple(cli_features, sizeof(cli_features) / sizeof(struct ast_cli_entry));
 554         ast_channel_unregister(&features_tech);
 555
 556         if (!AST_LIST_LOCK(&features))
 557                 return -1;
 558         /* Hangup all interfaces if they have an owner */
 559         while ((p = AST_LIST_REMOVE_HEAD(&features, list))) {
 560                 if (p->owner)
 561                         ast_softhangup(p->owner, AST_SOFTHANGUP_APPUNLOAD);
 562                 ast_free(p);
 563         }
 564         AST_LIST_UNLOCK(&features);
 565
 566         return 0;
 567 }
 568
 569 AST_MODULE_INFO_STANDARD(ASTERISK_GPL_KEY, "Feature Proxy Channel");
 570