mp3_afh.c

   1 /* Copyright (C) 2003 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
   2
   3 /** \file mp3_afh.c para_server's mp3 audio format handler */
   4
   5 /*
   6  * This file is based in part on mp3tech.c and mp3tech.h, Copyright (C)
   7  * 2000-2001 Cedric Tefft <cedric@earthling.net>, which in turn is based
   8  * in part on
   9  *
  10  *      * MP3Info 0.5 by Ricardo Cerqueira <rmc@rccn.net>
  11  *      * MP3Stat 0.9 by Ed Sweetman <safemode@voicenet.com> and
  12  *                       Johannes Overmann <overmann@iname.com>
  13  */
  14
  15 #include <regex.h>
  16
  17 #include "para.h"
  18 #include "error.h"
  19 #include "afh.h"
  20 #include "string.h"
  21 #include "fd.h"
  22
  23 /*
  24  * MIN_CONSEC_GOOD_FRAMES defines how many consecutive valid MP3 frames we need
  25  * to see before we decide we are looking at a real MP3 file
  26  */
  27 #define MIN_CONSEC_GOOD_FRAMES 4
  28 #define FRAME_HEADER_SIZE 4
  29 #define MIN_FRAME_SIZE 21
  30
  31 struct mp3header {
  32         unsigned long sync;
  33         unsigned int version;
  34         unsigned int layer;
  35         unsigned int crc;
  36         unsigned int bitrate;
  37         unsigned int freq;
  38         unsigned int padding;
  39         unsigned int mode;
  40         unsigned int copyright;
  41         unsigned int original;
  42         unsigned int emphasis;
  43 };
  44
  45 static const int frequencies[3][4] = {
  46         {22050,24000,16000,50000}, /* MPEG 2.0 */
  47         {44100,48000,32000,50000}, /* MPEG 1.0 */
  48         {11025,12000,8000,50000} /* MPEG 2.5 */
  49 };
  50
  51 static const int mp3info_bitrate[2][3][14] = {
  52 { /* MPEG 2.0 */
  53         {32,48,56,64,80,96,112,128,144,160,176,192,224,256}, /* layer 1 */
  54         {8,16,24,32,40,48,56,64,80,96,112,128,144,160}, /* layer 2 */
  55         {8,16,24,32,40,48,56,64,80,96,112,128,144,160} /* layer 3 */
  56 },
  57
  58 { /* MPEG 1.0 */
  59         {32,64,96,128,160,192,224,256,288,320,352,384,416,448}, /* layer 1 */
  60         {32,48,56,64,80,96,112,128,160,192,224,256,320,384}, /* layer 2 */
  61         {32,40,48,56,64,80,96,112,128,160,192,224,256,320} /* layer 3 */
  62 }
  63 };
  64
  65 static const int frame_size_index[] = {24000, 72000, 72000};
  66 #ifdef HAVE_ID3TAG
  67
  68 #include <id3tag.h>
  69
  70 static char *get_utf8(id3_ucs4_t const *string)
  71 {
  72         if (!string)
  73                 return NULL;
  74         return (char *)id3_ucs4_utf8duplicate(string);
  75 }
  76
  77 static char *get_stringlist(union id3_field *field)
  78 {
  79         unsigned int k, nstrings = id3_field_getnstrings(field);
  80         char *result = NULL;
  81
  82         for (k = 0; k < nstrings; k++) {
  83                 char *tmp = (char *)get_utf8(id3_field_getstrings(field, k));
  84                 if (result) {
  85                         char *tmp2 = result;
  86                         result = make_message("%s %s", tmp2, tmp);
  87                         free(tmp);
  88                         free(tmp2);
  89                 } else
  90                         result = tmp;
  91         }
  92         return result;
  93 }
  94
  95 static char *get_string(union id3_field *field)
  96 {
  97         id3_ucs4_t const *string = id3_field_getfullstring(field);
  98
  99         return get_utf8(string);
 100 }
 101
 102 #define FOR_EACH_FIELD(f, j, fr) for (j = 0; j < (fr)->nfields && \
 103         (f = id3_frame_field((fr), j)); j++)
 104
 105 static char *get_strings(struct id3_frame *fr)
 106 {
 107         int j;
 108         union id3_field *field;
 109
 110         FOR_EACH_FIELD(field, j, fr) {
 111                 enum id3_field_type type = id3_field_type(field);
 112
 113                 if (type == ID3_FIELD_TYPE_STRINGLIST)
 114                         return get_stringlist(field);
 115                 if (type == ID3_FIELD_TYPE_STRINGFULL)
 116                         return get_string(field);
 117         }
 118         return NULL;
 119 }
 120
 121 /* this only sets values which are undefined so far */
 122 static void parse_frames(struct id3_tag *id3_t, struct taginfo *tags)
 123 {
 124         int i;
 125
 126         for (i = 0; i < id3_t->nframes; i++) {
 127                 struct id3_frame *fr = id3_t->frames[i];
 128                 if (!strcmp(fr->id, ID3_FRAME_TITLE)) {
 129                         if (!tags->title)
 130                                 tags->title = get_strings(fr);
 131                         continue;
 132                 }
 133                 if (!strcmp(fr->id, ID3_FRAME_ARTIST)) {
 134                         if (!tags->artist)
 135                                 tags->artist = get_strings(fr);
 136                         continue;
 137                 }
 138                 if (!strcmp(fr->id, ID3_FRAME_ALBUM)) {
 139                         if (!tags->album)
 140                                 tags->album = get_strings(fr);
 141                         continue;
 142                 }
 143                 if (!strcmp(fr->id, ID3_FRAME_YEAR)) {
 144                         if (!tags->year)
 145                                 tags->year = get_strings(fr);
 146                         continue;
 147                 }
 148                 if (!strcmp(fr->id, ID3_FRAME_COMMENT)) {
 149                         if (!tags->comment)
 150                                 tags->comment = get_strings(fr);
 151                         continue;
 152                 }
 153         }
 154 }
 155
 156 static int mp3_get_id3(unsigned char *map, size_t numbytes, __a_unused int fd,
 157                 struct taginfo *tags)
 158 {
 159         int ret = 0;
 160         struct id3_tag *id3_t;
 161
 162         /* id3v2 tags are usually located at the beginning. */
 163         id3_t = id3_tag_parse(map, numbytes);
 164         if (id3_t) {
 165                 parse_frames(id3_t, tags);
 166                 ret |= 2;
 167                 id3_tag_delete(id3_t);
 168         }
 169         /* Also look for an id3v1 tag at the end of the file. */
 170         if (numbytes >= 128) {
 171                 id3_t = id3_tag_parse(map + numbytes - 128, 128);
 172                 if (id3_t) {
 173                         parse_frames(id3_t, tags);
 174                         ret |= 1;
 175                         id3_tag_delete(id3_t);
 176                 }
 177         }
 178         return ret;
 179 }
 180
 181 /* These helpers are not mentioned in the libid3tag header file. */
 182 void id3_field_init(union id3_field *field, enum id3_field_type type);
 183 void id3_field_finish(union id3_field *field);
 184
 185 /*
 186  * Frames of type ID3_FRAME_COMMENT contain three fields of type language,
 187  * string, and fullstring. The third field contains the actual comment.
 188  */
 189 static int set_comment_fields(struct id3_frame *fr, id3_ucs4_t *ucs4_val)
 190 {
 191         int ret;
 192         union id3_field *field;
 193
 194         field = id3_frame_field(fr, 1);
 195         id3_field_init(field, ID3_FIELD_TYPE_LANGUAGE);
 196
 197         field = id3_frame_field(fr, 2);
 198         id3_field_init(field, ID3_FIELD_TYPE_STRING);
 199
 200         field = id3_frame_field(fr, 3);
 201         id3_field_init(field, ID3_FIELD_TYPE_STRINGFULL);
 202         ret = id3_field_setfullstring(field, ucs4_val);
 203         if (ret < 0)
 204                 return -E_ID3_SETSTRING;
 205         return 1;
 206 }
 207
 208 /*
 209  * UCS-4 stands for Universal Character Set where each character uses exactly
 210  * 32 bits. It is also known as UTF-32, see ISO 10646.
 211  *
 212  * We have to use UCS-4 as an intermediate representation because the functions
 213  * of libid3tag which set the tag content expect an array of UCS-4 characters.
 214  * Fortunately, libid3tag contains conversion functions from and to UTF-8.
 215  */
 216 static int replace_tag(char const *id, const char *val, struct id3_tag *id3_t,
 217                 int options)
 218 {
 219         int ret;
 220         struct id3_frame *fr;
 221         union id3_field *field;
 222         id3_ucs4_t *ucs4_val;
 223
 224         /* First, detach all frames that match the given id. */
 225         while ((fr = id3_tag_findframe(id3_t, id, 0))) {
 226                 PARA_INFO_LOG("deleting %s frame\n", id);
 227                 ret = id3_tag_detachframe(id3_t, fr);
 228                 if (ret < 0)
 229                         return -E_ID3_DETACH;
 230                 id3_frame_delete(fr);
 231         }
 232         if (!val || !*val)
 233                 return 0;
 234         fr = id3_frame_new(id);
 235         PARA_DEBUG_LOG("frame desc: %s, %u fields\n", fr->description, fr->nfields);
 236
 237         /* Frame 0 contains the encoding. We always use UTF-8. */
 238         field = id3_frame_field(fr, 0);
 239         id3_field_init(field, ID3_FIELD_TYPE_TEXTENCODING);
 240         ret = id3_field_settextencoding(field, ID3_FIELD_TEXTENCODING_UTF_8);
 241         if (ret < 0)
 242                 return -E_ID3_SETENCODING;
 243         /* create UCS-4 representation */
 244         ucs4_val = id3_utf8_ucs4duplicate((const id3_utf8_t *)val);
 245
 246         if (strcmp(id, ID3_FRAME_COMMENT) == 0)
 247                 ret = set_comment_fields(fr, ucs4_val);
 248         else {
 249                 /* Non-comment frames contain the value in field 1. */
 250                 field = id3_frame_field(fr, 1);
 251                 if (options & ID3_TAG_OPTION_ID3V1) {
 252                         id3_ucs4_t *ptr[] = {ucs4_val, NULL};
 253                         id3_field_init(field, ID3_FIELD_TYPE_STRINGLIST);
 254                         ret = id3_field_setstrings(field, 1, ptr);
 255                 } else {
 256                         id3_field_init(field, ID3_FIELD_TYPE_STRINGFULL);
 257                         ret = id3_field_setfullstring(field, ucs4_val);
 258                 }
 259         }
 260         free(ucs4_val);
 261         if (ret < 0)
 262                 return -E_ID3_SETSTRING;
 263
 264         PARA_INFO_LOG("attaching %s frame, value: %s\n", id, val);
 265         ret = id3_tag_attachframe(id3_t, fr);
 266         if (ret < 0)
 267                 return -E_ID3_ATTACH;
 268         return 1;
 269 }
 270
 271 static int replace_tags(struct id3_tag *id3_t, struct taginfo *tags)
 272 {
 273         int ret, options = id3_tag_options(id3_t, 0, 0);
 274
 275         ret = replace_tag(ID3_FRAME_ARTIST, tags->artist, id3_t, options);
 276         if (ret < 0)
 277                 return ret;
 278         ret = replace_tag(ID3_FRAME_TITLE, tags->title, id3_t, options);
 279         if (ret < 0)
 280                 return ret;
 281         ret = replace_tag(ID3_FRAME_ALBUM, tags->album, id3_t, options);
 282         if (ret < 0)
 283                 return ret;
 284         ret = replace_tag(ID3_FRAME_YEAR, tags->year, id3_t, options);
 285         if (ret < 0)
 286                 return ret;
 287         ret = replace_tag(ID3_FRAME_COMMENT, tags->comment, id3_t, options);
 288         if (ret < 0)
 289                 return ret;
 290         return 1;
 291 }
 292
 293 /* id3_tag_delete() does not seem to work due to refcount issues. */
 294 static void free_tag(struct id3_tag *id3_t)
 295 {
 296         int i, j;
 297
 298         if (!id3_t)
 299                 return;
 300         for (i = 0; i < id3_t->nframes; i++) {
 301                 struct id3_frame *fr = id3_t->frames[i];
 302                 for (j = 0; j < fr->nfields; j++) {
 303                         union id3_field *field = &fr->fields[j];
 304                         id3_field_finish(field);
 305                 }
 306                 free(fr);
 307         }
 308         free(id3_t->frames);
 309         free(id3_t);
 310 }
 311
 312 static int mp3_rewrite_tags(const char *map, size_t mapsize,
 313                 struct taginfo *tags, int fd, __a_unused const char *filename)
 314 {
 315         int ret;
 316         id3_length_t old_v2size, new_v2size;
 317         id3_byte_t v1_buffer[128], *v2_buffer;
 318         size_t data_sz;
 319         struct id3_tag *v1_tag = NULL, *v2_tag = NULL;
 320
 321         if (mapsize >= 128) {
 322                 v1_tag = id3_tag_parse((const id3_byte_t *)map + mapsize - 128,
 323                         128);
 324                 if (v1_tag) {
 325                         PARA_NOTICE_LOG("replacing id3v1 tag\n");
 326                         ret = replace_tags(v1_tag, tags);
 327                         if (ret < 0)
 328                                 goto out;
 329                         id3_tag_render(v1_tag, v1_buffer);
 330                 }
 331         }
 332         old_v2size = 0;
 333         v2_tag = id3_tag_parse((const id3_byte_t *)map, mapsize);
 334         if (v2_tag) {
 335                 PARA_NOTICE_LOG("replacing id3v2 tag\n");
 336                 old_v2size = v2_tag->paddedsize;
 337         } else {
 338                 PARA_NOTICE_LOG("adding id3v2 tag\n");
 339                 v2_tag = id3_tag_new();
 340                 assert(v2_tag);
 341         }
 342         /*
 343          * Turn off all options to avoid creating an extended header.  id321
 344          * does not understand it.
 345          */
 346         id3_tag_options(v2_tag, ~0U, 0);
 347         ret = replace_tags(v2_tag, tags);
 348         if (ret < 0)
 349                 goto out;
 350         new_v2size = id3_tag_render(v2_tag, NULL);
 351         v2_buffer = para_malloc(new_v2size);
 352         id3_tag_render(v2_tag, v2_buffer);
 353         PARA_INFO_LOG("writing v2 tag (%lu bytes)\n", new_v2size);
 354         ret = write_all(fd, (char *)v2_buffer, new_v2size);
 355         free(v2_buffer);
 356         if (ret < 0)
 357                 goto out;
 358         data_sz = mapsize - old_v2size;
 359         if (v1_tag && data_sz >= 128)
 360                 data_sz -= 128;
 361         PARA_INFO_LOG("writing data part (%zu bytes)\n", data_sz);
 362         ret = write_all(fd, map + old_v2size, data_sz);
 363         if (ret < 0)
 364                 goto out;
 365         if (v1_tag) {
 366                 PARA_INFO_LOG("writing v1 tag\n");
 367                 ret = write_all(fd, (char *)v1_buffer, 128);
 368         }
 369 out:
 370         free_tag(v1_tag);
 371         free_tag(v2_tag);
 372         return ret;
 373 }
 374
 375 #else /* HAVE_ID3TAG */
 376
 377 /*
 378  * Remove trailing whitespace from the end of a string
 379  */
 380 static char *unpad(char *string)
 381 {
 382         char *pos = string + strlen(string) - 1;
 383         while (para_isspace(pos[0]))
 384                 (pos--)[0] = 0;
 385         return string;
 386 }
 387
 388 static int mp3_get_id3(unsigned char *map, size_t numbytes, __a_unused int fd,
 389         struct taginfo *tags)
 390 {
 391         char title[31], artist[31], album[31], year[5], comment[31];
 392         off_t fpos;
 393
 394         if (numbytes < 128 || strncmp("TAG", (char *)map + numbytes - 128, 3)) {
 395                 PARA_DEBUG_LOG("no id3 v1 tag\n");
 396                 return 0;
 397         }
 398         fpos = numbytes - 125;
 399         memcpy(title, map + fpos, 30);
 400         fpos += 30;
 401         title[30] = '\0';
 402         memcpy(artist, map + fpos, 30);
 403         fpos += 30;
 404         artist[30] = '\0';
 405         memcpy(album, map + fpos, 30);
 406         fpos += 30;
 407         album[30] = '\0';
 408         memcpy(year, map + fpos, 4);
 409         fpos += 4;
 410         year[4] = '\0';
 411         memcpy(comment, map + fpos, 30);
 412         comment[30] = '\0';
 413         unpad(title);
 414         unpad(artist);
 415         unpad(album);
 416         unpad(year);
 417         unpad(comment);
 418         tags->artist = para_strdup(artist);
 419         tags->title = para_strdup(title);
 420         tags->year = para_strdup(year);
 421         tags->album = para_strdup(album);
 422         tags->comment = para_strdup(comment);
 423         return 1;
 424 }
 425 #endif /* HAVE_ID3TAG */
 426
 427 static int header_frequency(struct mp3header *h)
 428 {
 429         if (h->version > 2 || h->freq > 3)
 430                 return -E_HEADER_FREQ;
 431         return frequencies[h->version][h->freq];
 432 }
 433
 434 static const char *header_mode(const struct mp3header *h)
 435 {
 436         const char * const mode_text[] = {"stereo", "joint stereo",
 437                 "dual channel", "mono"};
 438
 439         if (h->mode >= ARRAY_SIZE(mode_text))
 440                 return "invalid";
 441         return mode_text[h->mode];
 442 }
 443
 444 static int header_channels(struct mp3header *h)
 445 {
 446         if (h->mode > 3)
 447                 return 0;
 448         if (h->mode < 3)
 449                 return 2;
 450         return 1;
 451 }
 452
 453 static int header_bitrate(struct mp3header *h)
 454 {
 455         if (!h->layer || h->layer > 3 || h->bitrate > 14 || !h->bitrate)
 456                 return -E_HEADER_BITRATE;
 457         return mp3info_bitrate[h->version & 1][3 - h->layer][h->bitrate - 1];
 458 }
 459
 460 static int frame_length(struct mp3header *header)
 461 {
 462         int hb, hf = header_frequency(header);
 463
 464         if (hf < 0)
 465                 return hf;
 466         hb = header_bitrate(header);
 467         if (hb < 0)
 468                 return hb;
 469         if (header->sync != 0xFFE || header->layer > 3)
 470                 return -E_FRAME;
 471         return frame_size_index[3 - header->layer] *
 472                 ((header->version & 1) + 1) * hb / hf
 473                 + header->padding;
 474 }
 475
 476 static int compare_headers(struct mp3header *h1,struct mp3header *h2)
 477 {
 478         if ((*(unsigned int*)h1) == (*(unsigned int*)h2))
 479                 return 1;
 480         if ((h1->version == h2->version) &&
 481                         (h1->layer == h2->layer) &&
 482                         (h1->crc == h2->crc) &&
 483                         (h1->freq == h2->freq) &&
 484                         (h1->mode == h2->mode) &&
 485                         (h1->copyright == h2->copyright) &&
 486                         (h1->original == h2->original) &&
 487                         (h1->emphasis == h2->emphasis))
 488                 return 1;
 489         return 0;
 490 }
 491
 492 /*
 493  * get next MP3 frame header.
 494  *
 495  * On success, the header frame length is returned and the given header
 496  * structure that is filled in.  A return value of zero means that we did not
 497  * retrieve a valid frame header, and a negative return value indicates an
 498  * error.
 499  */
 500 static int get_header(unsigned char *map, size_t numbytes, off_t *fpos,
 501         struct mp3header *header)
 502 {
 503         int fl, ret;
 504
 505         if (*fpos + FRAME_HEADER_SIZE > numbytes) {
 506                 *fpos = numbytes - 1;
 507                 header->sync = 0;
 508                 return 0;
 509         }
 510         header->layer = (map[*fpos + 1] >> 1) & 3;
 511         header->sync = (((int)map[*fpos]<<4) | ((int)(map[*fpos + 1]&0xE0)>>4));
 512         if (map[*fpos + 1] & 0x10)
 513                 header->version = (map[*fpos + 1] >> 3) & 1;
 514         else
 515                 header->version = 2;
 516         if ((header->sync != 0xFFE) || (header->layer != 1)) {
 517                 ret = 0;
 518                 header->sync = 0;
 519                 goto out;
 520         }
 521         header->crc = map[*fpos + 1] & 1;
 522         header->bitrate = (map[*fpos + 2] >> 4) & 0x0F;
 523         header->freq = (map[*fpos + 2] >> 2) & 0x3;
 524         header->padding = (map[*fpos + 2] >>1) & 0x1;
 525         header->mode = (map[*fpos + 3] >> 6) & 0x3;
 526         fl = frame_length(header);
 527         ret = (fl >= MIN_FRAME_SIZE)? fl : -E_FRAME_LENGTH;
 528 out:
 529         *fpos += FRAME_HEADER_SIZE;
 530         return ret;
 531 }
 532
 533 /*
 534  * find the next mp3 header
 535  *
 536  * Return the length of the next frame header or zero if the end of the file is
 537  * reached.
 538  */
 539 static int mp3_seek_next_header(unsigned char *map, size_t numbytes, off_t *fpos,
 540         struct mp3header *result)
 541 {
 542         int k, l = 0, first_len;
 543         struct mp3header h, h2;
 544         long valid_start = 0;
 545
 546         for (; *fpos < numbytes; (*fpos)++) {
 547                 if (map[*fpos] != 0xff)
 548                         continue;
 549                 valid_start = *fpos;
 550                 first_len = get_header(map, numbytes, fpos, &h);
 551                 if (first_len <= 0)
 552                         continue;
 553                 *fpos += first_len - FRAME_HEADER_SIZE;
 554                 for (k = 1; k < MIN_CONSEC_GOOD_FRAMES; k++) {
 555                         if ((l = get_header(map, numbytes, fpos, &h2)) <= 0)
 556                                 break;
 557                         if (!compare_headers(&h, &h2))
 558                                 break;
 559                         *fpos += l - FRAME_HEADER_SIZE;
 560                 }
 561                 if (k == MIN_CONSEC_GOOD_FRAMES) {
 562                         *fpos = valid_start;
 563                         *result = h2;
 564                         return first_len;
 565                 }
 566         }
 567         return 0;
 568 }
 569
 570 static int find_valid_start(unsigned char *map, size_t numbytes, off_t *fpos,
 571         struct mp3header *header)
 572 {
 573         int frame_len;
 574
 575         frame_len = get_header(map, numbytes, fpos, header);
 576         if (frame_len < 0)
 577                 return frame_len;
 578         if (!frame_len) {
 579                 frame_len = mp3_seek_next_header(map, numbytes, fpos, header);
 580                 if (frame_len <= 0)
 581                         return frame_len;
 582         } else
 583                 *fpos -= FRAME_HEADER_SIZE;
 584         if (frame_len <= 1)
 585                 return -E_FRAME_LENGTH;
 586         return frame_len;
 587 }
 588
 589 static int mp3_read_info(unsigned char *map, size_t numbytes, int fd,
 590                 struct afh_info *afhi)
 591 {
 592         uint64_t freq_sum = 0, br_sum = 0;
 593         int fl = 0, ret, len = 0, old_br = -1, vbr = 0;
 594         struct timeval total_time = {0, 0};
 595         unsigned chunk_table_size = 1000; /* gets increased on demand */
 596         off_t fpos = 0;
 597         struct mp3header header;
 598         const char *tag_versions[] = {"no", "id3v1", "id3v2", "id3v1+id3v2"};
 599
 600         afhi->chunks_total = 0;
 601         afhi->chunk_table = para_malloc(chunk_table_size * sizeof(uint32_t));
 602         while (1) {
 603                 int freq, br;
 604                 struct timeval tmp, cct; /* current chunk time */
 605                 fpos += len;
 606                 len = find_valid_start(map, numbytes, &fpos, &header);
 607                 if (len <= 0) {
 608                         size_t end;
 609                         ret = -E_MP3_INFO;
 610                         if (!afhi->chunks_total)
 611                                 goto err_out;
 612                         end = afhi->chunk_table[afhi->chunks_total - 1] + fl;
 613                         afhi->chunk_table[afhi->chunks_total]
 614                                 = PARA_MIN(end, numbytes);
 615                         break;
 616                 }
 617                 ret = header_frequency(&header);
 618                 if (ret < 0)
 619                         continue;
 620                 freq = ret;
 621                 ret = header_bitrate(&header);
 622                 if (ret < 0)
 623                         continue;
 624                 br = ret;
 625                 ret = frame_length(&header);
 626                 if (ret < 0)
 627                         continue;
 628                 fl = ret;
 629                 tmp.tv_sec = fl - header.padding;
 630                 tmp.tv_usec = 0;
 631                 tv_divide(br * 125, &tmp, &cct);
 632                 tv_add(&cct, &total_time, &tmp);
 633                 total_time = tmp;
 634                 if (afhi->chunks_total >= chunk_table_size) {
 635                         chunk_table_size *= 2;
 636                         afhi->chunk_table = para_realloc(afhi->chunk_table,
 637                                 chunk_table_size * sizeof(uint32_t));
 638                 }
 639                 afhi->chunk_table[afhi->chunks_total] = fpos;
 640                 afhi->chunks_total++;
 641                 freq_sum += freq;
 642                 br_sum += br;
 643                 if (afhi->chunks_total != 1 && old_br != br)
 644                         vbr = 1;
 645                 old_br = br;
 646         }
 647         ret = -E_MP3_INFO;
 648         if (!freq_sum || !br_sum)
 649                 goto err_out;
 650         afhi->bitrate = br_sum / afhi->chunks_total;
 651         afhi->frequency = freq_sum / afhi->chunks_total;
 652         afhi->channels = header_channels(&header);
 653         afhi->seconds_total = (tv2ms(&total_time) + 500) / 1000;
 654         tv_divide(afhi->chunks_total, &total_time, &afhi->chunk_tv);
 655         PARA_DEBUG_LOG("%" PRIu32 " chunks, each %lums\n", afhi->chunks_total,
 656                 tv2ms(&afhi->chunk_tv));
 657         set_max_chunk_size(afhi);
 658         ret = mp3_get_id3(map, numbytes, fd, &afhi->tags);
 659         afhi->techinfo = make_message("%cbr, %s, %s tags", vbr? 'v' : 'c',
 660                 header_mode(&header), tag_versions[ret]);
 661         return 1;
 662 err_out:
 663         free(afhi->chunk_table);
 664         return ret;
 665 }
 666
 667 /*
 668  * Read mp3 information from audio file
 669  */
 670 static int mp3_get_file_info(char *map, size_t numbytes, int fd,
 671                 struct afh_info *afhi)
 672 {
 673         int ret;
 674
 675         ret = mp3_read_info((unsigned char *)map, numbytes, fd, afhi);
 676         if (ret < 0)
 677                 return ret;
 678         if (afhi->chunks_total == 0)
 679                 return -E_MP3_INFO;
 680         return 1;
 681 }
 682
 683 static const char * const mp3_suffixes[] = {"mp3", NULL};
 684
 685 /**
 686  * The mp3 audio format handler.
 687  *
 688  * It does not depend on any libraries and is hence always compiled in.
 689  */
 690 const struct audio_format_handler mp3_afh = {
 691         .get_file_info = mp3_get_file_info,
 692         .suffixes = mp3_suffixes,
 693 #ifdef HAVE_LIBID3TAG
 694         .rewrite_tags = mp3_rewrite_tags,
 695 #endif /* HAVE_LIBID3TAG */
 696 };