channels/chan_features.c

   1 /*
   2  * Asterisk -- A telephony toolkit for Linux.
   3  *
   4  * feature Proxy Channel
   5  *
   6  * Copyright (C) 1999, Mark Spencer
   7  *
   8  * Mark Spencer <markster@linux-support.net>
   9  *
  10  * This program is free software, distributed under the terms of
  11  * the GNU General Public License
  12  */
  13
  14 #include <stdio.h>
  15 #include <string.h>
  16 #include "asterisk/lock.h"
  17 #include "asterisk/channel.h"
  18 #include "asterisk/config.h"
  19 #include "asterisk/logger.h"
  20 #include "asterisk/module.h"
  21 #include "asterisk/pbx.h"
  22 #include "asterisk/options.h"
  23 #include "asterisk/lock.h"
  24 #include "asterisk/sched.h"
  25 #include "asterisk/io.h"
  26 #include "asterisk/rtp.h"
  27 #include "asterisk/acl.h"
  28 #include "asterisk/callerid.h"
  29 #include "asterisk/file.h"
  30 #include "asterisk/cli.h"
  31 #include "asterisk/app.h"
  32 #include "asterisk/musiconhold.h"
  33 #include "asterisk/manager.h"
  34 #include <sys/socket.h>
  35 #include <errno.h>
  36 #include <unistd.h>
  37 #include <stdlib.h>
  38 #include <fcntl.h>
  39 #include <netdb.h>
  40 #include <arpa/inet.h>
  41 #include <sys/signal.h>
  42
  43
  44 static const char desc[] = "Feature Proxy Channel";
  45 static const char type[] = "Feature";
  46 static const char tdesc[] = "Feature Proxy Channel Driver";
  47
  48 static int usecnt =0;
  49 AST_MUTEX_DEFINE_STATIC(usecnt_lock);
  50
  51 #define IS_OUTBOUND(a,b) (a == b->chan ? 1 : 0)
  52
  53 /* Protect the interface list (of feature_pvt's) */
  54 AST_MUTEX_DEFINE_STATIC(featurelock);
  55
  56 struct feature_sub {
  57         struct ast_channel *owner;
  58         int inthreeway;
  59         int pfd;
  60         int timingfdbackup;
  61         int alertpipebackup[2];
  62 };
  63
  64 static struct feature_pvt {
  65         ast_mutex_t lock;                               /* Channel private lock */
  66         char tech[AST_MAX_EXTENSION];   /* Technology to abstract */
  67         char dest[AST_MAX_EXTENSION];   /* Destination to abstract */
  68         struct ast_channel *subchan;
  69         struct feature_sub subs[3];             /* Subs */
  70         struct ast_channel *owner;                      /* Current Master Channel */
  71         struct feature_pvt *next;                               /* Next entity */
  72 } *features = NULL;
  73
  74 #define SUB_REAL                0                       /* Active call */
  75 #define SUB_CALLWAIT    1                       /* Call-Waiting call on hold */
  76 #define SUB_THREEWAY    2                       /* Three-way call */
  77
  78 static struct ast_channel *features_request(const char *type, int format, void *data, int *cause);
  79 static int features_digit(struct ast_channel *ast, char digit);
  80 static int features_call(struct ast_channel *ast, char *dest, int timeout);
  81 static int features_hangup(struct ast_channel *ast);
  82 static int features_answer(struct ast_channel *ast);
  83 static struct ast_frame *features_read(struct ast_channel *ast);
  84 static int features_write(struct ast_channel *ast, struct ast_frame *f);
  85 static int features_indicate(struct ast_channel *ast, int condition);
  86 static int features_fixup(struct ast_channel *oldchan, struct ast_channel *newchan);
  87
  88 static const struct ast_channel_tech features_tech = {
  89         .type = type,
  90         .description = tdesc,
  91         .capabilities = -1,
  92         .requester = features_request,
  93         .send_digit = features_digit,
  94         .call = features_call,
  95         .hangup = features_hangup,
  96         .answer = features_answer,
  97         .read = features_read,
  98         .write = features_write,
  99         .exception = features_read,
 100         .indicate = features_indicate,
 101         .fixup = features_fixup,
 102 };
 103
 104 static inline void init_sub(struct feature_sub *sub)
 105 {
 106         sub->inthreeway = 0;
 107         sub->pfd = -1;
 108         sub->timingfdbackup = -1;
 109         sub->alertpipebackup[0] = sub->alertpipebackup[1] = -1;
 110 }
 111
 112 static inline int indexof(struct feature_pvt *p, struct ast_channel *owner, int nullok)
 113 {
 114         int x;
 115         if (!owner) {
 116                 ast_log(LOG_WARNING, "indexof called on NULL owner??\n");
 117                 return -1;
 118         }
 119         for (x=0;x<3;x++) {
 120                 if (owner == p->subs[x].owner)
 121                         return x;
 122         }
 123         return -1;
 124 }
 125
 126 #if 0
 127 static void wakeup_sub(struct feature_pvt *p, int a)
 128 {
 129         struct ast_frame null = { AST_FRAME_NULL, };
 130         for (;;) {
 131                 if (p->subs[a].owner) {
 132                         if (ast_mutex_trylock(&p->subs[a].owner->lock)) {
 133                                 ast_mutex_unlock(&p->lock);
 134                                 usleep(1);
 135                                 ast_mutex_lock(&p->lock);
 136                         } else {
 137                                 ast_queue_frame(p->subs[a].owner, &null);
 138                                 ast_mutex_unlock(&p->subs[a].owner->lock);
 139                                 break;
 140                         }
 141                 } else
 142                         break;
 143         }
 144 }
 145 #endif
 146
 147 static void restore_channel(struct feature_pvt *p, int index)
 148 {
 149         /* Restore timing/alertpipe */
 150         p->subs[index].owner->timingfd = p->subs[index].timingfdbackup;
 151         p->subs[index].owner->alertpipe[0] = p->subs[index].alertpipebackup[0];
 152         p->subs[index].owner->alertpipe[1] = p->subs[index].alertpipebackup[1];
 153         p->subs[index].owner->fds[AST_MAX_FDS-1] = p->subs[index].alertpipebackup[0];
 154         p->subs[index].owner->fds[AST_MAX_FDS-2] = p->subs[index].timingfdbackup;
 155 }
 156
 157 static void update_features(struct feature_pvt *p, int index)
 158 {
 159         int x;
 160         if (p->subs[index].owner) {
 161                 for (x=0;x<AST_MAX_FDS;x++) {
 162                         if (index)
 163                                 p->subs[index].owner->fds[x] = -1;
 164                         else
 165                                 p->subs[index].owner->fds[x] = p->subchan->fds[x];
 166                 }
 167                 if (!index) {
 168                         /* Copy timings from master channel */
 169                         p->subs[index].owner->timingfd = p->subchan->timingfd;
 170                         p->subs[index].owner->alertpipe[0] = p->subchan->alertpipe[0];
 171                         p->subs[index].owner->alertpipe[1] = p->subchan->alertpipe[1];
 172                         if (p->subs[index].owner->nativeformats != p->subchan->readformat) {
 173                                 p->subs[index].owner->nativeformats = p->subchan->readformat;
 174                                 if (p->subs[index].owner->readformat)
 175                                         ast_set_read_format(p->subs[index].owner, p->subs[index].owner->readformat);
 176                                 if (p->subs[index].owner->writeformat)
 177                                         ast_set_write_format(p->subs[index].owner, p->subs[index].owner->writeformat);
 178                         }
 179                 } else{
 180                         restore_channel(p, index);
 181                 }
 182         }
 183 }
 184
 185 #if 0
 186 static void swap_subs(struct feature_pvt *p, int a, int b)
 187 {
 188         int tinthreeway;
 189         struct ast_channel *towner;
 190
 191         ast_log(LOG_DEBUG, "Swapping %d and %d\n", a, b);
 192
 193         towner = p->subs[a].owner;
 194         tinthreeway = p->subs[a].inthreeway;
 195
 196         p->subs[a].owner = p->subs[b].owner;
 197         p->subs[a].inthreeway = p->subs[b].inthreeway;
 198
 199         p->subs[b].owner = towner;
 200         p->subs[b].inthreeway = tinthreeway;
 201         update_features(p,a);
 202         update_features(p,b);
 203         wakeup_sub(p, a);
 204         wakeup_sub(p, b);
 205 }
 206 #endif
 207
 208 static int features_answer(struct ast_channel *ast)
 209 {
 210         struct feature_pvt *p = ast->tech_pvt;
 211         int res = -1;
 212         int x;
 213         ast_mutex_lock(&p->lock);
 214         x = indexof(p, ast, 0);
 215         if (!x && p->subchan)
 216                 res = ast_answer(p->subchan);
 217         ast_mutex_unlock(&p->lock);
 218         return res;
 219 }
 220
 221 static struct ast_frame  *features_read(struct ast_channel *ast)
 222 {
 223         static struct ast_frame null_frame = { AST_FRAME_NULL, };
 224         struct feature_pvt *p = ast->tech_pvt;
 225         struct ast_frame *f;
 226         int x;
 227
 228         f = &null_frame;
 229         ast_mutex_lock(&p->lock);
 230         x = indexof(p, ast, 0);
 231         if (!x && p->subchan) {
 232                 update_features(p, x);
 233                 f = ast_read(p->subchan);
 234         }
 235         ast_mutex_unlock(&p->lock);
 236         return f;
 237 }
 238
 239 static int features_write(struct ast_channel *ast, struct ast_frame *f)
 240 {
 241         struct feature_pvt *p = ast->tech_pvt;
 242         int res = -1;
 243         int x;
 244         ast_mutex_lock(&p->lock);
 245         x = indexof(p, ast, 0);
 246         if (!x && p->subchan)
 247                 res = ast_write(p->subchan, f);
 248         ast_mutex_unlock(&p->lock);
 249         return res;
 250 }
 251
 252 static int features_fixup(struct ast_channel *oldchan, struct ast_channel *newchan)
 253 {
 254         struct feature_pvt *p = newchan->tech_pvt;
 255         int x;
 256         ast_mutex_lock(&p->lock);
 257         if (p->owner == oldchan)
 258                 p->owner = newchan;
 259         for (x=0;x<3;x++) {
 260                 if (p->subs[x].owner == oldchan)
 261                         p->subs[x].owner = newchan;
 262         }
 263         ast_mutex_unlock(&p->lock);
 264         return 0;
 265 }
 266
 267 static int features_indicate(struct ast_channel *ast, int condition)
 268 {
 269         struct feature_pvt *p = ast->tech_pvt;
 270         int res = -1;
 271         int x;
 272         /* Queue up a frame representing the indication as a control frame */
 273         ast_mutex_lock(&p->lock);
 274         x = indexof(p, ast, 0);
 275         if (!x && p->subchan)
 276                 res = ast_indicate(p->subchan, condition);
 277         ast_mutex_unlock(&p->lock);
 278         return res;
 279 }
 280
 281 static int features_digit(struct ast_channel *ast, char digit)
 282 {
 283         struct feature_pvt *p = ast->tech_pvt;
 284         int res = -1;
 285         int x;
 286         /* Queue up a frame representing the indication as a control frame */
 287         ast_mutex_lock(&p->lock);
 288         x = indexof(p, ast, 0);
 289         if (!x && p->subchan)
 290                 res = ast_senddigit(p->subchan, digit);
 291         ast_mutex_unlock(&p->lock);
 292         return res;
 293 }
 294
 295 static int features_call(struct ast_channel *ast, char *dest, int timeout)
 296 {
 297         struct feature_pvt *p = ast->tech_pvt;
 298         int res = -1;
 299         int x;
 300         char *dest2;
 301
 302         dest2 = strchr(dest, '/');
 303         if (dest2) {
 304                 ast_mutex_lock(&p->lock);
 305                 x = indexof(p, ast, 0);
 306                 if (!x && p->subchan) {
 307                         if (p->owner->cid.cid_num)
 308                                 p->subchan->cid.cid_num = strdup(p->owner->cid.cid_num);
 309                         else
 310                                 p->subchan->cid.cid_num = NULL;
 311
 312                         if (p->owner->cid.cid_name)
 313                                 p->subchan->cid.cid_name = strdup(p->owner->cid.cid_name);
 314                         else
 315                                 p->subchan->cid.cid_name = NULL;
 316
 317                         if (p->owner->cid.cid_rdnis)
 318                                 p->subchan->cid.cid_rdnis = strdup(p->owner->cid.cid_rdnis);
 319                         else
 320                                 p->subchan->cid.cid_rdnis = NULL;
 321
 322                         if (p->owner->cid.cid_ani)
 323                                 p->subchan->cid.cid_ani = strdup(p->owner->cid.cid_ani);
 324                         else
 325                                 p->subchan->cid.cid_ani = NULL;
 326
 327                         strncpy(p->subchan->language, p->owner->language, sizeof(p->subchan->language) - 1);
 328                         strncpy(p->subchan->accountcode, p->owner->accountcode, sizeof(p->subchan->accountcode) - 1);
 329                         p->subchan->cdrflags = p->owner->cdrflags;
 330                         res = ast_call(p->subchan, dest2, timeout);
 331                         update_features(p, x);
 332                 } else
 333                         ast_log(LOG_NOTICE, "Uhm yah, not quite there with the call waiting...\n");
 334                 ast_mutex_unlock(&p->lock);
 335         }
 336         return res;
 337 }
 338
 339 static int features_hangup(struct ast_channel *ast)
 340 {
 341         struct feature_pvt *p = ast->tech_pvt;
 342         struct feature_pvt *cur, *prev=NULL;
 343         int x;
 344
 345         ast_mutex_lock(&p->lock);
 346         x = indexof(p, ast, 0);
 347         if (x > -1) {
 348                 restore_channel(p, x);
 349                 p->subs[x].owner = NULL;
 350                 /* XXX Re-arrange, unconference, etc XXX */
 351         }
 352         ast->tech_pvt = NULL;
 353
 354
 355         if (!p->subs[SUB_REAL].owner && !p->subs[SUB_CALLWAIT].owner && !p->subs[SUB_THREEWAY].owner) {
 356                 ast_mutex_unlock(&p->lock);
 357                 /* Remove from list */
 358                 ast_mutex_lock(&featurelock);
 359                 cur = features;
 360                 while(cur) {
 361                         if (cur == p) {
 362                                 if (prev)
 363                                         prev->next = cur->next;
 364                                 else
 365                                         features = cur->next;
 366                                 break;
 367                         }
 368                         prev = cur;
 369                         cur = cur->next;
 370                 }
 371                 ast_mutex_unlock(&featurelock);
 372                 ast_mutex_lock(&p->lock);
 373                 /* And destroy */
 374                 if (p->subchan)
 375                         ast_hangup(p->subchan);
 376                 ast_mutex_unlock(&p->lock);
 377                 ast_mutex_destroy(&p->lock);
 378                 free(p);
 379                 return 0;
 380         }
 381         ast_mutex_unlock(&p->lock);
 382         return 0;
 383 }
 384
 385 static struct feature_pvt *features_alloc(char *data, int format)
 386 {
 387         struct feature_pvt *tmp;
 388         char *dest=NULL;
 389         char *tech;
 390         int x;
 391         int status;
 392         struct ast_channel *chan;
 393
 394         tech = ast_strdupa(data);
 395         if (tech) {
 396                 dest = strchr(tech, '/');
 397                 if (dest) {
 398                         *dest = '\0';
 399                         dest++;
 400                 }
 401         }
 402         if (!tech || !dest) {
 403                 ast_log(LOG_NOTICE, "Format for feature channel is Feature/Tech/Dest ('%s' not valid)!\n",
 404                         data);
 405                 return NULL;
 406         }
 407         ast_mutex_lock(&featurelock);
 408         tmp = features;
 409         while(tmp) {
 410                 if (!strcasecmp(tmp->tech, tech) && !strcmp(tmp->dest, dest))
 411                         break;
 412                 tmp = tmp->next;
 413         }
 414         ast_mutex_unlock(&featurelock);
 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 = malloc(sizeof(struct feature_pvt));
 422                 if (tmp) {
 423                         memset(tmp, 0, sizeof(struct feature_pvt));
 424                         for (x=0;x<3;x++)
 425                                 init_sub(tmp->subs + x);
 426                         ast_mutex_init(&tmp->lock);
 427                         strncpy(tmp->tech, tech, sizeof(tmp->tech) - 1);
 428                         strncpy(tmp->dest, dest, sizeof(tmp->dest) - 1);
 429                         tmp->subchan = chan;
 430                         ast_mutex_lock(&featurelock);
 431                         tmp->next = features;
 432                         features = tmp;
 433                         ast_mutex_unlock(&featurelock);
 434                 }
 435         }
 436         return tmp;
 437 }
 438
 439 static struct ast_channel *features_new(struct feature_pvt *p, int state, int index)
 440 {
 441         struct ast_channel *tmp;
 442         int x,y;
 443         if (!p->subchan) {
 444                 ast_log(LOG_WARNING, "Called upon channel with no subchan:(\n");
 445                 return NULL;
 446         }
 447         if (p->subs[index].owner) {
 448                 ast_log(LOG_WARNING, "Called to put index %d already there!\n", index);
 449                 return NULL;
 450         }
 451         tmp = ast_channel_alloc(0);
 452         if (!tmp)
 453                 return NULL;
 454         if (tmp) {
 455                 tmp->tech = &features_tech;
 456                 for (x=1;x<4;x++) {
 457                         snprintf(tmp->name, sizeof(tmp->name), "Feature/%s/%s-%d", p->tech, p->dest, x);
 458                         for (y=0;y<3;y++) {
 459                                 if (y == index)
 460                                         continue;
 461                                 if (p->subs[x].owner && !strcasecmp(p->subs[x].owner->name, tmp->name))
 462                                         break;
 463                         }
 464                         if (y >= 3)
 465                                 break;
 466                 }
 467                 tmp->type = type;
 468                 ast_setstate(tmp, state);
 469                 tmp->writeformat = p->subchan->writeformat;
 470                 tmp->rawwriteformat = p->subchan->rawwriteformat;
 471                 tmp->readformat = p->subchan->readformat;
 472                 tmp->rawreadformat = p->subchan->rawreadformat;
 473                 tmp->nativeformats = p->subchan->readformat;
 474                 tmp->tech_pvt = p;
 475                 p->subs[index].owner = tmp;
 476                 if (!p->owner)
 477                         p->owner = tmp;
 478                 ast_mutex_lock(&usecnt_lock);
 479                 usecnt++;
 480                 ast_mutex_unlock(&usecnt_lock);
 481                 ast_update_use_count();
 482         } else
 483                 ast_log(LOG_WARNING, "Unable to allocate channel structure\n");
 484         return tmp;
 485 }
 486
 487
 488 static struct ast_channel *features_request(const char *type, int format, void *data, int *cause)
 489 {
 490         struct feature_pvt *p;
 491         struct ast_channel *chan = NULL;
 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 int features_show(int fd, int argc, char **argv)
 501 {
 502         struct feature_pvt *p;
 503
 504         if (argc != 3)
 505                 return RESULT_SHOWUSAGE;
 506         ast_mutex_lock(&featurelock);
 507         p = features;
 508         while(p) {
 509                 ast_mutex_lock(&p->lock);
 510                 ast_cli(fd, "%s -- %s/%s\n", p->owner ? p->owner->name : "<unowned>", p->tech, p->dest);
 511                 ast_mutex_unlock(&p->lock);
 512                 p = p->next;
 513         }
 514         if (!features)
 515                 ast_cli(fd, "No feature channels in use\n");
 516         ast_mutex_unlock(&featurelock);
 517         return RESULT_SUCCESS;
 518 }
 519
 520 static char show_features_usage[] =
 521 "Usage: feature show channels\n"
 522 "       Provides summary information on feature channels.\n";
 523
 524 static struct ast_cli_entry cli_show_features = {
 525         { "feature", "show", "channels", NULL }, features_show,
 526         "Show status of feature channels", show_features_usage, NULL };
 527
 528 int load_module()
 529 {
 530         /* Make sure we can register our sip channel type */
 531         if (ast_channel_register(&features_tech)) {
 532                 ast_log(LOG_ERROR, "Unable to register channel class %s\n", type);
 533                 return -1;
 534         }
 535         ast_cli_register(&cli_show_features);
 536         return 0;
 537 }
 538
 539 int reload()
 540 {
 541         return 0;
 542 }
 543
 544 int unload_module()
 545 {
 546         struct feature_pvt *p;
 547         /* First, take us out of the channel loop */
 548         ast_cli_unregister(&cli_show_features);
 549         ast_channel_unregister(&features_tech);
 550         if (!ast_mutex_lock(&featurelock)) {
 551                 /* Hangup all interfaces if they have an owner */
 552                 p = features;
 553                 while(p) {
 554                         if (p->owner)
 555                                 ast_softhangup(p->owner, AST_SOFTHANGUP_APPUNLOAD);
 556                         p = p->next;
 557                 }
 558                 features = NULL;
 559                 ast_mutex_unlock(&featurelock);
 560         } else {
 561                 ast_log(LOG_WARNING, "Unable to lock the monitor\n");
 562                 return -1;
 563         }
 564         return 0;
 565 }
 566
 567 int usecount()
 568 {
 569         int res;
 570         ast_mutex_lock(&usecnt_lock);
 571         res = usecnt;
 572         ast_mutex_unlock(&usecnt_lock);
 573         return res;
 574 }
 575
 576 char *key()
 577 {
 578         return ASTERISK_GPL_KEY;
 579 }
 580
 581 char *description()
 582 {
 583         return (char *) desc;
 584 }
 585