formats/format_mp3.c

   1 /*
   2  * Asterisk -- A telephony toolkit for Linux.
   3  *
   4  * Everybody's favorite format: MP3 Files!  Yay!
   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 <asterisk/lock.h>
  15 #include <asterisk/channel.h>
  16 #include <asterisk/file.h>
  17 #include <asterisk/logger.h>
  18 #include <asterisk/sched.h>
  19 #include <asterisk/module.h>
  20 #include <arpa/inet.h>
  21 #include <stdlib.h>
  22 #include <stdio.h>
  23 #include <unistd.h>
  24 #include <errno.h>
  25 #include <string.h>
  26 #include <pthread.h>
  27 #include <sys/time.h>
  28 #include "../channels/adtranvofr.h"
  29
  30 #define MAX_FRAME_SIZE 1441
  31
  32 struct ast_filestream {
  33         /* First entry MUST be reserved for the channel type */
  34         void *reserved[AST_RESERVED_POINTERS];
  35         /* This is what a filestream means to us */
  36         int fd; /* Descriptor */
  37         struct ast_channel *owner;
  38         struct ast_filestream *next;
  39         struct ast_frame fr;    /* Frame representation of buf */
  40         char offset[AST_FRIENDLY_OFFSET];
  41         unsigned char buf[MAX_FRAME_SIZE * 2];
  42         int lasttimeout;
  43         int pos;
  44         int adj;
  45         struct timeval last;
  46 };
  47
  48
  49 static struct ast_filestream *glist = NULL;
  50 static pthread_mutex_t mp3_lock = AST_MUTEX_INITIALIZER;
  51 static int glistcnt = 0;
  52
  53 static char *name = "mp3";
  54 static char *desc = "MPEG-1,2 Layer 3 File Format Support";
  55 static char *exts = "mp3|mpeg3";
  56
  57 #include "../codecs/mp3anal.h"
  58
  59 static struct ast_filestream *mp3_open(int fd)
  60 {
  61         /* We don't have any header to read or anything really, but
  62            if we did, it would go here.  We also might want to check
  63            and be sure it's a valid file.  */
  64         struct ast_filestream *tmp;
  65         if ((tmp = malloc(sizeof(struct ast_filestream)))) {
  66                 if (ast_pthread_mutex_lock(&mp3_lock)) {
  67                         ast_log(LOG_WARNING, "Unable to lock mp3 list\n");
  68                         free(tmp);
  69                         return NULL;
  70                 }
  71                 tmp->next = glist;
  72                 glist = tmp;
  73                 tmp->fd = fd;
  74                 tmp->owner = NULL;
  75                 tmp->lasttimeout = -1;
  76                 tmp->last.tv_usec = 0;
  77                 tmp->last.tv_sec = 0;
  78                 tmp->adj = 0;
  79                 glistcnt++;
  80                 ast_pthread_mutex_unlock(&mp3_lock);
  81                 ast_update_use_count();
  82         }
  83         return tmp;
  84 }
  85
  86 static struct ast_filestream *mp3_rewrite(int fd, char *comment)
  87 {
  88         /* We don't have any header to read or anything really, but
  89            if we did, it would go here.  We also might want to check
  90            and be sure it's a valid file.  */
  91         struct ast_filestream *tmp;
  92         if ((tmp = malloc(sizeof(struct ast_filestream)))) {
  93                 if (ast_pthread_mutex_lock(&mp3_lock)) {
  94                         ast_log(LOG_WARNING, "Unable to lock mp3 list\n");
  95                         free(tmp);
  96                         return NULL;
  97                 }
  98                 tmp->next = glist;
  99                 glist = tmp;
 100                 tmp->fd = fd;
 101                 tmp->owner = NULL;
 102                 glistcnt++;
 103                 ast_pthread_mutex_unlock(&mp3_lock);
 104                 ast_update_use_count();
 105         } else
 106                 ast_log(LOG_WARNING, "Out of memory\n");
 107         return tmp;
 108 }
 109
 110 static struct ast_frame *mp3_read(struct ast_filestream *s)
 111 {
 112         return NULL;
 113 }
 114
 115 static void mp3_close(struct ast_filestream *s)
 116 {
 117         struct ast_filestream *tmp, *tmpl = NULL;
 118         if (ast_pthread_mutex_lock(&mp3_lock)) {
 119                 ast_log(LOG_WARNING, "Unable to lock mp3 list\n");
 120                 return;
 121         }
 122         tmp = glist;
 123         while(tmp) {
 124                 if (tmp == s) {
 125                         if (tmpl)
 126                                 tmpl->next = tmp->next;
 127                         else
 128                                 glist = tmp->next;
 129                         break;
 130                 }
 131                 tmpl = tmp;
 132                 tmp = tmp->next;
 133         }
 134         glistcnt--;
 135         if (s->owner) {
 136                 s->owner->stream = NULL;
 137                 if (s->owner->streamid > -1)
 138                         ast_sched_del(s->owner->sched, s->owner->streamid);
 139                 s->owner->streamid = -1;
 140         }
 141         ast_pthread_mutex_unlock(&mp3_lock);
 142         ast_update_use_count();
 143         if (!tmp)
 144                 ast_log(LOG_WARNING, "Freeing a filestream we don't seem to own\n");
 145         close(s->fd);
 146         free(s);
 147 }
 148
 149 static int ast_read_callback(void *data)
 150 {
 151         /* XXX Don't assume frames are this size XXX */
 152         u_int32_t delay = -1;
 153         int res;
 154         struct ast_filestream *s = data;
 155         int size;
 156         int ms=0;
 157         struct timeval tv;
 158         if ((res = read(s->fd, s->buf , 4)) != 4) {
 159                 ast_log(LOG_WARNING, "Short read (%d of 4 bytes) (%s)!\n", res, strerror(errno));
 160                 s->owner->streamid = -1;
 161                 return 0;
 162         }
 163         if (mp3_badheader(s->buf)) {
 164                 ast_log(LOG_WARNING, "Bad mp3 header\n");
 165                 return 0;
 166         }
 167         if ((size = mp3_framelen(s->buf)) < 0) {
 168                 ast_log(LOG_WARNING, "Unable to calculate frame size\n");
 169                 return 0;
 170         }
 171         if ((res = read(s->fd, s->buf + 4 , size - 4)) != size - 4) {
 172                 ast_log(LOG_WARNING, "Short read (%d of %d bytes) (%s)!\n", res, size - 4, strerror(errno));
 173                 s->owner->streamid = -1;
 174                 return 0;
 175         }
 176         /* Send a frame from the file to the appropriate channel */
 177         /* Read the data into the buffer */
 178         s->fr.offset = AST_FRIENDLY_OFFSET;
 179         s->fr.frametype = AST_FRAME_VOICE;
 180         s->fr.subclass = AST_FORMAT_MP3;
 181         s->fr.mallocd = 0;
 182         s->fr.src = name;
 183         s->fr.datalen = size;
 184         s->fr.data = s->buf;
 185         delay = mp3_samples(s->buf) * 1000 / mp3_samplerate(s->buf);
 186         if (s->last.tv_sec || s->last.tv_usec) {
 187                 /* To keep things running smoothly, we watch how close we're coming */
 188                 gettimeofday(&tv, NULL);
 189                 ms = ((tv.tv_usec - s->last.tv_usec) / 1000 + (tv.tv_sec - s->last.tv_sec) * 1000);
 190                 /* If we're within 2 milliseconds, that's close enough */
 191                 if ((ms - delay) > 0 )
 192                         s->adj -= (ms - delay);
 193                 s->adj -= 2;
 194         }
 195         s->fr.timelen = delay;
 196 #if 0
 197         ast_log(LOG_DEBUG, "delay is %d, adjusting by %d, as last was %d\n", delay, s->adj, ms);
 198 #endif
 199         delay += s->adj;
 200         if (delay < 1)
 201                 delay = 1;
 202         /* Lastly, process the frame */
 203         if (ast_write(s->owner, &s->fr)) {
 204                 ast_log(LOG_WARNING, "Failed to write frame\n");
 205                 s->owner->streamid = -1;
 206                 return 0;
 207         }
 208         gettimeofday(&s->last, NULL);
 209         if (s->lasttimeout != delay) {
 210                 s->owner->streamid = ast_sched_add(s->owner->sched, delay, ast_read_callback, s);
 211                 s->lasttimeout = delay;
 212                 return 0;
 213         }
 214         return -1;
 215 }
 216
 217 static int mp3_apply(struct ast_channel *c, struct ast_filestream *s)
 218 {
 219         /* Select our owner for this stream, and get the ball rolling. */
 220         s->owner = c;
 221         ast_read_callback(s);
 222         return 0;
 223 }
 224
 225 static int mp3_write(struct ast_filestream *fs, struct ast_frame *f)
 226 {
 227         int res;
 228         if (f->frametype != AST_FRAME_VOICE) {
 229                 ast_log(LOG_WARNING, "Asked to write non-voice frame!\n");
 230                 return -1;
 231         }
 232         if (f->subclass != AST_FORMAT_MP3) {
 233                 ast_log(LOG_WARNING, "Asked to write non-mp3 frame!\n");
 234                 return -1;
 235         }
 236         if ((res = write(fs->fd, f->data, f->datalen)) != f->datalen) {
 237                 ast_log(LOG_WARNING, "Unable to write frame: res=%d (%s)\n", res, strerror(errno));
 238                 return -1;
 239         }
 240         return 0;
 241 }
 242
 243 static char *mp3_getcomment(struct ast_filestream *s)
 244 {
 245         return NULL;
 246 }
 247
 248 int load_module()
 249 {
 250         return ast_format_register(name, exts, AST_FORMAT_MP3,
 251                                                                 mp3_open,
 252                                                                 mp3_rewrite,
 253                                                                 mp3_apply,
 254                                                                 mp3_write,
 255                                                                 mp3_read,
 256                                                                 mp3_close,
 257                                                                 mp3_getcomment);
 258
 259
 260 }
 261
 262 int unload_module()
 263 {
 264         struct ast_filestream *tmp, *tmpl;
 265         if (ast_pthread_mutex_lock(&mp3_lock)) {
 266                 ast_log(LOG_WARNING, "Unable to lock mp3 list\n");
 267                 return -1;
 268         }
 269         tmp = glist;
 270         while(tmp) {
 271                 if (tmp->owner)
 272                         ast_softhangup(tmp->owner, AST_SOFTHANGUP_APPUNLOAD);
 273                 tmpl = tmp;
 274                 tmp = tmp->next;
 275                 free(tmpl);
 276         }
 277         ast_pthread_mutex_unlock(&mp3_lock);
 278         return ast_format_unregister(name);
 279 }
 280
 281 int usecount()
 282 {
 283         int res;
 284         if (ast_pthread_mutex_lock(&mp3_lock)) {
 285                 ast_log(LOG_WARNING, "Unable to lock mp3 list\n");
 286                 return -1;
 287         }
 288         res = glistcnt;
 289         ast_pthread_mutex_unlock(&mp3_lock);
 290         return res;
 291 }
 292
 293 char *description()
 294 {
 295         return desc;
 296 }
 297
 298
 299 char *key()
 300 {
 301         return ASTERISK_GPL_KEY;
 302 }