codecs/codec_dahdi.c

   1 /*
   2  * Asterisk -- An open source telephony toolkit.
   3  *
   4  * DAHDI native transcoding support
   5  *
   6  * Copyright (C) 1999 - 2006, Digium, Inc.
   7  *
   8  * Mark Spencer <markster@digium.com>
   9  * Kevin P. Fleming <kpfleming@digium.com>
  10  *
  11  * See http://www.asterisk.org for more information about
  12  * the Asterisk project. Please do not directly contact
  13  * any of the maintainers of this project for assistance;
  14  * the project provides a web site, mailing lists and IRC
  15  * channels for your use.
  16  *
  17  * This program is free software, distributed under the terms of
  18  * the GNU General Public License Version 2. See the LICENSE file
  19  * at the top of the source tree.
  20  */
  21
  22 /*! \file
  23  *
  24  * \brief Translate between various formats natively through DAHDI transcoding
  25  *
  26  * \ingroup codecs
  27  */
  28
  29 /*** MODULEINFO
  30         <depend>dahdi</depend>
  31  ***/
  32
  33 #include "asterisk.h"
  34
  35 ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
  36
  37 #include <fcntl.h>
  38 #include <netinet/in.h>
  39 #include <sys/ioctl.h>
  40 #include <sys/mman.h>
  41
  42 #include <dahdi/user.h>
  43
  44 #include "asterisk/lock.h"
  45 #include "asterisk/translate.h"
  46 #include "asterisk/config.h"
  47 #include "asterisk/module.h"
  48 #include "asterisk/cli.h"
  49 #include "asterisk/channel.h"
  50 #include "asterisk/utils.h"
  51 #include "asterisk/linkedlists.h"
  52
  53 #define BUFFER_SAMPLES  8000
  54
  55 static unsigned int global_useplc = 0;
  56
  57 static struct channel_usage {
  58         int total;
  59         int encoders;
  60         int decoders;
  61 } channels;
  62
  63 static char *handle_cli_transcoder_show(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a);
  64
  65 static struct ast_cli_entry cli[] = {
  66         AST_CLI_DEFINE(handle_cli_transcoder_show, "Display DAHDI transcoder utilization.")
  67 };
  68
  69 struct format_map {
  70         unsigned int map[32][32];
  71 };
  72
  73 static struct format_map global_format_map = { { { 0 } } };
  74
  75 struct translator {
  76         struct ast_translator t;
  77         AST_LIST_ENTRY(translator) entry;
  78 };
  79
  80 static AST_LIST_HEAD_STATIC(translators, translator);
  81
  82 struct pvt {
  83         int fd;
  84         int fake;
  85 #ifdef DEBUG_TRANSCODE
  86         int totalms;
  87         int lasttotalms;
  88 #endif
  89         struct dahdi_transcode_header *hdr;
  90 };
  91
  92 static char *handle_cli_transcoder_show(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
  93 {
  94         struct channel_usage copy;
  95
  96         switch (cmd) {
  97         case CLI_INIT:
  98                 e->command = "transcoder show";
  99                 e->usage =
 100                         "Usage: transcoder show\n"
 101                         "       Displays channel utilization of DAHDI transcoder(s).\n";
 102                 return NULL;
 103         case CLI_GENERATE:
 104                 return NULL;
 105         }
 106
 107         if (a->argc != 2)
 108                 return CLI_SHOWUSAGE;
 109
 110         copy = channels;
 111
 112         if (copy.total == 0)
 113                 ast_cli(a->fd, "No DAHDI transcoders found.\n");
 114         else
 115                 ast_cli(a->fd, "%d/%d encoders/decoders of %d channels are in use.\n", copy.encoders, copy.decoders, copy.total);
 116
 117         return CLI_SUCCESS;
 118 }
 119
 120 static int dahdi_framein(struct ast_trans_pvt *pvt, struct ast_frame *f)
 121 {
 122         struct pvt *dahdip = pvt->pvt;
 123         struct dahdi_transcode_header *hdr = dahdip->hdr;
 124
 125         if (!f->subclass) {
 126                 /* Fake a return frame for calculation purposes */
 127                 dahdip->fake = 2;
 128                 pvt->samples = f->samples;
 129                 return 0;
 130         }
 131
 132         if (!hdr->srclen)
 133                 /* Copy at front of buffer */
 134                 hdr->srcoffset = 0;
 135
 136         if (hdr->srclen + f->datalen > sizeof(hdr->srcdata)) {
 137                 ast_log(LOG_WARNING, "Out of space for codec translation!\n");
 138                 return -1;
 139         }
 140
 141         if (hdr->srclen + f->datalen + hdr->srcoffset > sizeof(hdr->srcdata)) {
 142                 /* Very unlikely */
 143                 memmove(hdr->srcdata, hdr->srcdata + hdr->srcoffset, hdr->srclen);
 144                 hdr->srcoffset = 0;
 145         }
 146
 147         memcpy(hdr->srcdata + hdr->srcoffset + hdr->srclen, f->data.ptr, f->datalen);
 148         hdr->srclen += f->datalen;
 149         pvt->samples += f->samples;
 150
 151         return -1;
 152 }
 153
 154 static struct ast_frame *dahdi_frameout(struct ast_trans_pvt *pvt)
 155 {
 156         struct pvt *dahdip = pvt->pvt;
 157         struct dahdi_transcode_header *hdr = dahdip->hdr;
 158         unsigned int x;
 159
 160         if (dahdip->fake == 2) {
 161                 dahdip->fake = 1;
 162                 pvt->f.frametype = AST_FRAME_VOICE;
 163                 pvt->f.subclass = 0;
 164                 pvt->f.samples = 160;
 165                 pvt->f.data.ptr = NULL;
 166                 pvt->f.offset = 0;
 167                 pvt->f.datalen = 0;
 168                 pvt->f.mallocd = 0;
 169                 ast_set_flag(&pvt->f, AST_FRFLAG_FROM_TRANSLATOR);
 170                 pvt->samples = 0;
 171         } else if (dahdip->fake == 1) {
 172                 return NULL;
 173         } else {
 174                 if (hdr->dstlen) {
 175 #ifdef DEBUG_TRANSCODE
 176                         dahdip->totalms += hdr->dstsamples;
 177                         if ((dahdip->totalms - dahdip->lasttotalms) > 8000) {
 178                                 printf("Whee %p, %d (%d to %d)\n", dahdip, hdr->dstlen, dahdip->lasttotalms, dahdip->totalms);
 179                                 dahdip->lasttotalms = dahdip->totalms;
 180                         }
 181 #endif
 182                         pvt->f.frametype = AST_FRAME_VOICE;
 183                         pvt->f.subclass = hdr->dstfmt;
 184                         pvt->f.samples = hdr->dstsamples;
 185                         pvt->f.data.ptr = hdr->dstdata + hdr->dstoffset;
 186                         pvt->f.offset = hdr->dstoffset;
 187                         pvt->f.datalen = hdr->dstlen;
 188                         pvt->f.mallocd = 0;
 189                         ast_set_flag(&pvt->f, AST_FRFLAG_FROM_TRANSLATOR);
 190                         pvt->samples -= pvt->f.samples;
 191                         hdr->dstlen = 0;
 192
 193                 } else {
 194                         if (hdr->srclen) {
 195                                 hdr->dstoffset = AST_FRIENDLY_OFFSET;
 196                                 x = DAHDI_TCOP_TRANSCODE;
 197                                 if (ioctl(dahdip->fd, DAHDI_TRANSCODE_OP, &x))
 198                                         ast_log(LOG_WARNING, "Failed to transcode: %s\n", strerror(errno));
 199                         }
 200                         return NULL;
 201                 }
 202         }
 203
 204         return &pvt->f;
 205 }
 206
 207 static void dahdi_destroy(struct ast_trans_pvt *pvt)
 208 {
 209         struct pvt *dahdip = pvt->pvt;
 210         unsigned int x;
 211
 212         x = DAHDI_TCOP_RELEASE;
 213         if (ioctl(dahdip->fd, DAHDI_TRANSCODE_OP, &x))
 214                 ast_log(LOG_WARNING, "Failed to release transcoder channel: %s\n", strerror(errno));
 215
 216         switch (dahdip->hdr->dstfmt) {
 217         case AST_FORMAT_G729A:
 218         case AST_FORMAT_G723_1:
 219                 ast_atomic_fetchadd_int(&channels.encoders, -1);
 220                 break;
 221         default:
 222                 ast_atomic_fetchadd_int(&channels.decoders, -1);
 223                 break;
 224         }
 225
 226         munmap(dahdip->hdr, sizeof(*dahdip->hdr));
 227         close(dahdip->fd);
 228 }
 229
 230 static int dahdi_translate(struct ast_trans_pvt *pvt, int dest, int source)
 231 {
 232         /* Request translation through dahdi if possible */
 233         int fd;
 234         unsigned int x = DAHDI_TCOP_ALLOCATE;
 235         struct pvt *dahdip = pvt->pvt;
 236         struct dahdi_transcode_header *hdr;
 237         int flags;
 238
 239         if ((fd = open("/dev/dahdi/transcode", O_RDWR)) < 0)
 240                 return -1;
 241         flags = fcntl(fd, F_GETFL);
 242         if (flags > - 1) {
 243                 if (fcntl(fd, F_SETFL, flags | O_NONBLOCK))
 244                         ast_log(LOG_WARNING, "Could not set non-block mode!\n");
 245         }
 246
 247
 248         if ((hdr = mmap(NULL, sizeof(*hdr), PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0)) == MAP_FAILED) {
 249                 ast_log(LOG_ERROR, "Memory Map failed for transcoding (%s)\n", strerror(errno));
 250                 close(fd);
 251
 252                 return -1;
 253         }
 254
 255         if (hdr->magic != DAHDI_TRANSCODE_MAGIC) {
 256                 ast_log(LOG_ERROR, "Transcoder header (%08x) wasn't magic.  Abandoning\n", hdr->magic);
 257                 munmap(hdr, sizeof(*hdr));
 258                 close(fd);
 259
 260                 return -1;
 261         }
 262
 263         hdr->srcfmt = (1 << source);
 264         hdr->dstfmt = (1 << dest);
 265         if (ioctl(fd, DAHDI_TRANSCODE_OP, &x)) {
 266                 ast_log(LOG_ERROR, "Unable to attach transcoder: %s\n", strerror(errno));
 267                 munmap(hdr, sizeof(*hdr));
 268                 close(fd);
 269
 270                 return -1;
 271         }
 272
 273         dahdip = pvt->pvt;
 274         dahdip->fd = fd;
 275         dahdip->hdr = hdr;
 276
 277         switch (hdr->dstfmt) {
 278         case AST_FORMAT_G729A:
 279         case AST_FORMAT_G723_1:
 280                 ast_atomic_fetchadd_int(&channels.encoders, +1);
 281                 break;
 282         default:
 283                 ast_atomic_fetchadd_int(&channels.decoders, +1);
 284                 break;
 285         }
 286
 287         return 0;
 288 }
 289
 290 static int dahdi_new(struct ast_trans_pvt *pvt)
 291 {
 292         return dahdi_translate(pvt, pvt->t->dstfmt, pvt->t->srcfmt);
 293 }
 294
 295 static struct ast_frame *fakesrc_sample(void)
 296 {
 297         /* Don't bother really trying to test hardware ones. */
 298         static struct ast_frame f = {
 299                 .frametype = AST_FRAME_VOICE,
 300                 .samples = 160,
 301                 .src = __PRETTY_FUNCTION__
 302         };
 303
 304         return &f;
 305 }
 306
 307 static int register_translator(int dst, int src)
 308 {
 309         struct translator *dahdi;
 310         int res;
 311
 312         if (!(dahdi = ast_calloc(1, sizeof(*dahdi))))
 313                 return -1;
 314
 315         snprintf((char *) (dahdi->t.name), sizeof(dahdi->t.name), "DAHDI%sto%s",
 316                  ast_getformatname((1 << src)), ast_getformatname((1 << dst)));
 317         dahdi->t.srcfmt = (1 << src);
 318         dahdi->t.dstfmt = (1 << dst);
 319         dahdi->t.newpvt = dahdi_new;
 320         dahdi->t.framein = dahdi_framein;
 321         dahdi->t.frameout = dahdi_frameout;
 322         dahdi->t.destroy = dahdi_destroy;
 323         dahdi->t.sample = fakesrc_sample;
 324         dahdi->t.useplc = global_useplc;
 325         dahdi->t.buf_size = BUFFER_SAMPLES * 2;
 326         dahdi->t.desc_size = sizeof(struct pvt);
 327         if ((res = ast_register_translator(&dahdi->t))) {
 328                 ast_free(dahdi);
 329                 return -1;
 330         }
 331
 332         AST_LIST_LOCK(&translators);
 333         AST_LIST_INSERT_HEAD(&translators, dahdi, entry);
 334         AST_LIST_UNLOCK(&translators);
 335
 336         global_format_map.map[dst][src] = 1;
 337
 338         return res;
 339 }
 340
 341 static void drop_translator(int dst, int src)
 342 {
 343         struct translator *cur;
 344
 345         AST_LIST_LOCK(&translators);
 346         AST_LIST_TRAVERSE_SAFE_BEGIN(&translators, cur, entry) {
 347                 if (cur->t.srcfmt != src)
 348                         continue;
 349
 350                 if (cur->t.dstfmt != dst)
 351                         continue;
 352
 353                 AST_LIST_REMOVE_CURRENT(entry);
 354                 ast_unregister_translator(&cur->t);
 355                 ast_free(cur);
 356                 global_format_map.map[dst][src] = 0;
 357                 break;
 358         }
 359         AST_LIST_TRAVERSE_SAFE_END;
 360         AST_LIST_UNLOCK(&translators);
 361 }
 362
 363 static void unregister_translators(void)
 364 {
 365         struct translator *current;
 366
 367         AST_LIST_LOCK(&translators);
 368         while ((current = AST_LIST_REMOVE_HEAD(&translators, entry))) {
 369                 ast_unregister_translator(&current->t);
 370                 ast_free(current);
 371         }
 372         AST_LIST_UNLOCK(&translators);
 373 }
 374
 375 static int parse_config(int reload)
 376 {
 377         struct ast_variable *var;
 378         struct ast_flags config_flags = { reload ? CONFIG_FLAG_FILEUNCHANGED : 0 };
 379         struct ast_config *cfg = ast_config_load("codecs.conf", config_flags);
 380
 381         if (cfg == NULL)
 382                 return 0;
 383         if (cfg == CONFIG_STATUS_FILEUNCHANGED)
 384                 return 0;
 385
 386         for (var = ast_variable_browse(cfg, "plc"); var; var = var->next) {
 387                if (!strcasecmp(var->name, "genericplc")) {
 388                        global_useplc = ast_true(var->value);
 389                            ast_verb(3, "codec_dahdi: %susing generic PLC\n",
 390                                            global_useplc ? "" : "not ");
 391                }
 392         }
 393         ast_config_destroy(cfg);
 394         return 0;
 395 }
 396
 397 static void build_translators(struct format_map *map, unsigned int dstfmts, unsigned int srcfmts)
 398 {
 399         unsigned int src, dst;
 400
 401         for (src = 0; src < 32; src++) {
 402                 for (dst = 0; dst < 32; dst++) {
 403                         if (!(srcfmts & (1 << src)))
 404                                 continue;
 405
 406                         if (!(dstfmts & (1 << dst)))
 407                                 continue;
 408
 409                         if (global_format_map.map[dst][src])
 410                                 continue;
 411
 412                         if (!register_translator(dst, src))
 413                                 map->map[dst][src] = 1;
 414                 }
 415         }
 416 }
 417
 418 static int find_transcoders(void)
 419 {
 420         struct dahdi_transcode_info info = { 0, };
 421         struct format_map map = { { { 0 } } };
 422         int fd, res;
 423         unsigned int x, y;
 424
 425         if ((fd = open("/dev/dahdi/transcode", O_RDWR)) < 0) {
 426                 ast_verbose(VERBOSE_PREFIX_2 "No hardware transcoders found.\n");
 427                 return 0;
 428         }
 429
 430         info.op = DAHDI_TCOP_GETINFO;
 431         for (info.tcnum = 0; !(res = ioctl(fd, DAHDI_TRANSCODE_OP, &info)); info.tcnum++) {
 432                 ast_verb(2, "Found transcoder '%s'.\n", info.name);
 433                 build_translators(&map, info.dstfmts, info.srcfmts);
 434                 ast_atomic_fetchadd_int(&channels.total, info.numchannels / 2);
 435         }
 436
 437         close(fd);
 438
 439         if (!info.tcnum)
 440                 ast_verb(2, "No hardware transcoders found.\n");
 441
 442         for (x = 0; x < 32; x++) {
 443                 for (y = 0; y < 32; y++) {
 444                         if (!map.map[x][y] && global_format_map.map[x][y])
 445                                 drop_translator(x, y);
 446                 }
 447         }
 448
 449         return 0;
 450 }
 451
 452 static int reload(void)
 453 {
 454         struct translator *cur;
 455
 456         if (parse_config(1))
 457                 return AST_MODULE_LOAD_DECLINE;
 458
 459         AST_LIST_LOCK(&translators);
 460         AST_LIST_TRAVERSE(&translators, cur, entry)
 461                 cur->t.useplc = global_useplc;
 462         AST_LIST_UNLOCK(&translators);
 463
 464         return AST_MODULE_LOAD_SUCCESS;
 465 }
 466
 467 static int unload_module(void)
 468 {
 469         ast_cli_unregister_multiple(cli, ARRAY_LEN(cli));
 470         unregister_translators();
 471
 472         return 0;
 473 }
 474
 475 static int load_module(void)
 476 {
 477         if (parse_config(0))
 478                 return AST_MODULE_LOAD_DECLINE;
 479         find_transcoders();
 480         ast_cli_register_multiple(cli, ARRAY_LEN(cli));
 481         return AST_MODULE_LOAD_SUCCESS;
 482 }
 483
 484 AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_DEFAULT, "Generic DAHDI Transcoder Codec Translator",
 485                 .load = load_module,
 486                 .unload = unload_module,
 487                 .reload = reload,
 488                 );