src/libFLAC/metadata_object.c

   1 /* libFLAC - Free Lossless Audio Codec library
   2  * Copyright (C) 2001,2002  Josh Coalson
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Library General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Library General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Library General Public
  15  * License along with this library; if not, write to the
  16  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17  * Boston, MA  02111-1307, USA.
  18  */
  19
  20 #include <stdlib.h>
  21 #include <string.h>
  22
  23 #include "private/metadata.h"
  24
  25 #include "FLAC/assert.h"
  26
  27
  28 /****************************************************************************
  29  *
  30  * Local routines
  31  *
  32  ***************************************************************************/
  33
  34 static FLAC__bool copy_bytes_(FLAC__byte **to, const FLAC__byte *from, unsigned bytes)
  35 {
  36         if(bytes > 0 && 0 != from) {
  37                 FLAC__byte *x;
  38                 if(0 == (x = malloc(bytes)))
  39                         return false;
  40                 memcpy(x, from, bytes);
  41                 *to = x;
  42         }
  43         else {
  44                 FLAC__ASSERT(0 == from);
  45                 FLAC__ASSERT(bytes == 0);
  46                 *to = 0;
  47         }
  48         return true;
  49 }
  50
  51 static FLAC__bool copy_vcentry_(FLAC__StreamMetadata_VorbisComment_Entry *to, const FLAC__StreamMetadata_VorbisComment_Entry *from)
  52 {
  53         to->length = from->length;
  54         if(0 == from->entry) {
  55                 FLAC__ASSERT(from->length == 0);
  56                 to->entry = 0;
  57         }
  58         else {
  59                 FLAC__byte *x;
  60                 FLAC__ASSERT(from->length > 0);
  61                 if(0 == (x = malloc(from->length)))
  62                         return false;
  63                 memcpy(x, from->entry, from->length);
  64                 to->entry = x;
  65         }
  66         return true;
  67 }
  68
  69 static void seektable_calculate_length_(FLAC__StreamMetadata *object)
  70 {
  71         FLAC__ASSERT(0 != object);
  72         FLAC__ASSERT(object->type == FLAC__METADATA_TYPE_SEEKTABLE);
  73
  74         object->length = object->data.seek_table.num_points * FLAC__STREAM_METADATA_SEEKPOINT_LENGTH;
  75 }
  76
  77 static FLAC__StreamMetadata_SeekPoint *seekpoint_array_new_(unsigned num_points)
  78 {
  79         FLAC__StreamMetadata_SeekPoint *object_array;
  80
  81         FLAC__ASSERT(num_points > 0);
  82
  83         object_array = malloc(num_points * sizeof(FLAC__StreamMetadata_SeekPoint));
  84
  85         if(0 != object_array) {
  86                 unsigned i;
  87                 for(i = 0; i < num_points; i++) {
  88                         object_array[i].sample_number = FLAC__STREAM_METADATA_SEEKPOINT_PLACEHOLDER;
  89                         object_array[i].stream_offset = 0;
  90                         object_array[i].frame_samples = 0;
  91                 }
  92         }
  93
  94         return object_array;
  95 }
  96
  97 static void vorbiscomment_calculate_length_(FLAC__StreamMetadata *object)
  98 {
  99         unsigned i;
 100
 101         FLAC__ASSERT(object->type == FLAC__METADATA_TYPE_VORBIS_COMMENT);
 102
 103         object->length = (FLAC__STREAM_METADATA_VORBIS_COMMENT_ENTRY_LENGTH_LEN) / 8;
 104         object->length += object->data.vorbis_comment.vendor_string.length;
 105         object->length += (FLAC__STREAM_METADATA_VORBIS_COMMENT_NUM_COMMENTS_LEN) / 8;
 106         for(i = 0; i < object->data.vorbis_comment.num_comments; i++) {
 107                 object->length += (FLAC__STREAM_METADATA_VORBIS_COMMENT_ENTRY_LENGTH_LEN / 8);
 108                 object->length += object->data.vorbis_comment.comments[i].length;
 109         }
 110 }
 111
 112 static FLAC__StreamMetadata_VorbisComment_Entry *vorbiscomment_entry_array_new_(unsigned num_comments)
 113 {
 114         FLAC__StreamMetadata_VorbisComment_Entry *object_array;
 115
 116         FLAC__ASSERT(num_comments > 0);
 117
 118         object_array = malloc(num_comments * sizeof(FLAC__StreamMetadata_VorbisComment_Entry));
 119
 120         if(0 != object_array)
 121                 memset(object_array, 0, num_comments * sizeof(FLAC__StreamMetadata_VorbisComment_Entry));
 122
 123         return object_array;
 124 }
 125
 126 static void vorbiscomment_entry_array_delete_(FLAC__StreamMetadata_VorbisComment_Entry *object_array, unsigned num_comments)
 127 {
 128         unsigned i;
 129
 130         FLAC__ASSERT(0 != object_array && num_comments > 0);
 131
 132         for(i = 0; i < num_comments; i++)
 133                 if(0 != object_array[i].entry)
 134                         free(object_array[i].entry);
 135
 136         if(0 != object_array)
 137                 free(object_array);
 138 }
 139
 140 static FLAC__StreamMetadata_VorbisComment_Entry *vorbiscomment_entry_array_copy_(const FLAC__StreamMetadata_VorbisComment_Entry *object_array, unsigned num_comments)
 141 {
 142         FLAC__StreamMetadata_VorbisComment_Entry *return_array;
 143
 144         FLAC__ASSERT(0 != object_array);
 145         FLAC__ASSERT(num_comments > 0);
 146
 147         return_array = vorbiscomment_entry_array_new_(num_comments);
 148
 149         if(0 != return_array) {
 150                 unsigned i;
 151
 152                 /* Need to do this to set the pointers inside the comments to 0.
 153                  * In case of an error in the following loop, the object will be
 154                  * deleted and we don't want the destructor freeing uninitialized
 155                  * pointers.
 156                  */
 157                 memset(return_array, 0, num_comments * sizeof(FLAC__StreamMetadata_VorbisComment_Entry));
 158
 159                 for(i = 0; i < num_comments; i++) {
 160                         if(!copy_vcentry_(return_array+i, object_array+i)) {
 161                                 vorbiscomment_entry_array_delete_(return_array, num_comments);
 162                                 return 0;
 163                         }
 164                 }
 165         }
 166
 167         return return_array;
 168 }
 169
 170 static FLAC__bool vorbiscomment_set_entry_(FLAC__StreamMetadata *object, FLAC__StreamMetadata_VorbisComment_Entry *dest, const FLAC__StreamMetadata_VorbisComment_Entry *src, FLAC__bool copy)
 171 {
 172         FLAC__byte *save;
 173
 174         FLAC__ASSERT(0 != object);
 175         FLAC__ASSERT(0 != dest);
 176         FLAC__ASSERT(0 != src);
 177         FLAC__ASSERT(object->type == FLAC__METADATA_TYPE_VORBIS_COMMENT);
 178         FLAC__ASSERT((0 != src->entry && src->length > 0) || (0 == src->entry && src->length == 0 && copy == false));
 179
 180         save = dest->entry;
 181
 182         /* do the copy first so that if we fail we leave the object untouched */
 183         if(copy) {
 184                 if(!copy_vcentry_(dest, src))
 185                         return false;
 186         }
 187         else {
 188                 *dest = *src;
 189         }
 190
 191         if(0 != save)
 192                 free(save);
 193
 194         vorbiscomment_calculate_length_(object);
 195         return true;
 196 }
 197
 198
 199 /****************************************************************************
 200  *
 201  * Metadata object routines
 202  *
 203  ***************************************************************************/
 204
 205 FLAC_API FLAC__StreamMetadata *FLAC__metadata_object_new(FLAC__MetadataType type)
 206 {
 207         FLAC__StreamMetadata *object = malloc(sizeof(FLAC__StreamMetadata));
 208         if(0 != object) {
 209                 memset(object, 0, sizeof(FLAC__StreamMetadata));
 210                 object->is_last = false;
 211                 object->type = type;
 212                 switch(type) {
 213                         case FLAC__METADATA_TYPE_STREAMINFO:
 214                                 object->length = FLAC__STREAM_METADATA_STREAMINFO_LENGTH;
 215                                 break;
 216                         case FLAC__METADATA_TYPE_PADDING:
 217                                 break;
 218                         case FLAC__METADATA_TYPE_APPLICATION:
 219                                 object->length = FLAC__STREAM_METADATA_APPLICATION_ID_LEN / 8;
 220                                 break;
 221                         case FLAC__METADATA_TYPE_SEEKTABLE:
 222                                 break;
 223                         case FLAC__METADATA_TYPE_VORBIS_COMMENT:
 224                                 object->length = (FLAC__STREAM_METADATA_VORBIS_COMMENT_ENTRY_LENGTH_LEN + FLAC__STREAM_METADATA_VORBIS_COMMENT_NUM_COMMENTS_LEN) / 8;
 225                                 break;
 226                         default:
 227                                 /* double protection: */
 228                                 FLAC__ASSERT(0);
 229                                 free(object);
 230                                 return 0;
 231                 }
 232         }
 233
 234         return object;
 235 }
 236
 237 FLAC_API FLAC__StreamMetadata *FLAC__metadata_object_clone(const FLAC__StreamMetadata *object)
 238 {
 239         FLAC__StreamMetadata *to;
 240
 241         FLAC__ASSERT(0 != object);
 242
 243         if(0 != (to = FLAC__metadata_object_new(object->type))) {
 244                 to->is_last = object->is_last;
 245                 to->type = object->type;
 246                 to->length = object->length;
 247                 switch(to->type) {
 248                         case FLAC__METADATA_TYPE_STREAMINFO:
 249                                 memcpy(&to->data.stream_info, &object->data.stream_info, sizeof(FLAC__StreamMetadata_StreamInfo));
 250                                 break;
 251                         case FLAC__METADATA_TYPE_PADDING:
 252                                 break;
 253                         case FLAC__METADATA_TYPE_APPLICATION:
 254                                 memcpy(&to->data.application.id, &object->data.application.id, FLAC__STREAM_METADATA_APPLICATION_ID_LEN / 8);
 255                                 if(!copy_bytes_(&to->data.application.data, object->data.application.data, object->length - FLAC__STREAM_METADATA_APPLICATION_ID_LEN / 8)) {
 256                                         FLAC__metadata_object_delete(to);
 257                                         return 0;
 258                                 }
 259                                 break;
 260                         case FLAC__METADATA_TYPE_SEEKTABLE:
 261                                 to->data.seek_table.num_points = object->data.seek_table.num_points;
 262                                 if(!copy_bytes_((FLAC__byte**)&to->data.seek_table.points, (FLAC__byte*)object->data.seek_table.points, object->data.seek_table.num_points * sizeof(FLAC__StreamMetadata_SeekPoint))) {
 263                                         FLAC__metadata_object_delete(to);
 264                                         return 0;
 265                                 }
 266                                 break;
 267                         case FLAC__METADATA_TYPE_VORBIS_COMMENT:
 268                                 if(!copy_vcentry_(&to->data.vorbis_comment.vendor_string, &object->data.vorbis_comment.vendor_string)) {
 269                                         FLAC__metadata_object_delete(to);
 270                                         return 0;
 271                                 }
 272                                 if(object->data.vorbis_comment.num_comments == 0) {
 273                                         FLAC__ASSERT(0 == object->data.vorbis_comment.comments);
 274                                         to->data.vorbis_comment.comments = 0;
 275                                 }
 276                                 else {
 277                                         FLAC__ASSERT(0 != object->data.vorbis_comment.comments);
 278                                         to->data.vorbis_comment.comments = vorbiscomment_entry_array_copy_(object->data.vorbis_comment.comments, object->data.vorbis_comment.num_comments);
 279                                         if(0 == to->data.vorbis_comment.comments) {
 280                                                 FLAC__metadata_object_delete(to);
 281                                                 return 0;
 282                                         }
 283                                 }
 284                                 to->data.vorbis_comment.num_comments = object->data.vorbis_comment.num_comments;
 285                                 break;
 286                         default:
 287                                 /* double protection: */
 288                                 FLAC__ASSERT(0);
 289                                 free(to);
 290                                 return 0;
 291                 }
 292         }
 293
 294         return to;
 295 }
 296
 297 void FLAC__metadata_object_delete_data(FLAC__StreamMetadata *object)
 298 {
 299         FLAC__ASSERT(0 != object);
 300
 301         switch(object->type) {
 302                 case FLAC__METADATA_TYPE_STREAMINFO:
 303                 case FLAC__METADATA_TYPE_PADDING:
 304                         break;
 305                 case FLAC__METADATA_TYPE_APPLICATION:
 306                         if(0 != object->data.application.data)
 307                                 free(object->data.application.data);
 308                         break;
 309                 case FLAC__METADATA_TYPE_SEEKTABLE:
 310                         if(0 != object->data.seek_table.points)
 311                                 free(object->data.seek_table.points);
 312                         break;
 313                 case FLAC__METADATA_TYPE_VORBIS_COMMENT:
 314                         if(0 != object->data.vorbis_comment.vendor_string.entry)
 315                                 free(object->data.vorbis_comment.vendor_string.entry);
 316                         if(0 != object->data.vorbis_comment.comments) {
 317                                 FLAC__ASSERT(object->data.vorbis_comment.num_comments > 0);
 318                                 vorbiscomment_entry_array_delete_(object->data.vorbis_comment.comments, object->data.vorbis_comment.num_comments);
 319                         }
 320                         break;
 321                 default:
 322                         FLAC__ASSERT(0);
 323         }
 324 }
 325
 326 FLAC_API void FLAC__metadata_object_delete(FLAC__StreamMetadata *object)
 327 {
 328         FLAC__metadata_object_delete_data(object);
 329         free(object);
 330 }
 331
 332 static FLAC__bool compare_block_data_streaminfo_(const FLAC__StreamMetadata_StreamInfo *block1, const FLAC__StreamMetadata_StreamInfo *block2)
 333 {
 334         if(block1->min_blocksize != block2->min_blocksize)
 335                 return false;
 336         if(block1->max_blocksize != block2->max_blocksize)
 337                 return false;
 338         if(block1->min_framesize != block2->min_framesize)
 339                 return false;
 340         if(block1->max_framesize != block2->max_framesize)
 341                 return false;
 342         if(block1->sample_rate != block2->sample_rate)
 343                 return false;
 344         if(block1->channels != block2->channels)
 345                 return false;
 346         if(block1->bits_per_sample != block2->bits_per_sample)
 347                 return false;
 348         if(block1->total_samples != block2->total_samples)
 349                 return false;
 350         if(0 != memcmp(block1->md5sum, block2->md5sum, 16))
 351                 return false;
 352         return true;
 353 }
 354
 355 static FLAC__bool compare_block_data_application_(const FLAC__StreamMetadata_Application *block1, const FLAC__StreamMetadata_Application *block2, unsigned block_length)
 356 {
 357         FLAC__ASSERT(0 != block1);
 358         FLAC__ASSERT(0 != block2);
 359         FLAC__ASSERT(block_length >= sizeof(block1->id));
 360
 361         if(0 != memcmp(block1->id, block2->id, sizeof(block1->id)))
 362                 return false;
 363         if(0 != block1->data && 0 != block2->data)
 364                 return 0 == memcmp(block1->data, block2->data, block_length - sizeof(block1->id));
 365         else
 366                 return block1->data == block2->data;
 367 }
 368
 369 static FLAC__bool compare_block_data_seektable_(const FLAC__StreamMetadata_SeekTable *block1, const FLAC__StreamMetadata_SeekTable *block2)
 370 {
 371         unsigned i;
 372
 373         FLAC__ASSERT(0 != block1);
 374         FLAC__ASSERT(0 != block2);
 375
 376         if(block1->num_points != block2->num_points)
 377                 return false;
 378
 379         if(0 != block1->points && 0 != block2->points) {
 380                 for(i = 0; i < block1->num_points; i++) {
 381                         if(block1->points[i].sample_number != block2->points[i].sample_number)
 382                                 return false;
 383                         if(block1->points[i].stream_offset != block2->points[i].stream_offset)
 384                                 return false;
 385                         if(block1->points[i].frame_samples != block2->points[i].frame_samples)
 386                                 return false;
 387                 }
 388                 return true;
 389         }
 390         else
 391                 return block1->points == block2->points;
 392 }
 393
 394 static FLAC__bool compare_block_data_vorbiscomment_(const FLAC__StreamMetadata_VorbisComment *block1, const FLAC__StreamMetadata_VorbisComment *block2)
 395 {
 396         unsigned i;
 397
 398         if(block1->vendor_string.length != block2->vendor_string.length)
 399                 return false;
 400
 401         if(0 != block1->vendor_string.entry && 0 != block2->vendor_string.entry) {
 402                 if(0 != memcmp(block1->vendor_string.entry, block2->vendor_string.entry, block1->vendor_string.length))
 403                         return false;
 404         }
 405         else if(block1->vendor_string.entry != block2->vendor_string.entry)
 406                 return false;
 407
 408         if(block1->num_comments != block2->num_comments)
 409                 return false;
 410
 411         for(i = 0; i < block1->num_comments; i++) {
 412                 if(0 != block1->comments[i].entry && 0 != block2->comments[i].entry) {
 413                         if(0 != memcmp(block1->comments[i].entry, block2->comments[i].entry, block1->comments[i].length))
 414                                 return false;
 415                 }
 416                 else if(block1->comments[i].entry != block2->comments[i].entry)
 417                         return false;
 418         }
 419         return true;
 420 }
 421
 422 FLAC_API FLAC__bool FLAC__metadata_object_is_equal(const FLAC__StreamMetadata *block1, const FLAC__StreamMetadata *block2)
 423 {
 424         FLAC__ASSERT(0 != block1);
 425         FLAC__ASSERT(0 != block2);
 426
 427         if(block1->type != block2->type) {
 428                 return false;
 429         }
 430         if(block1->is_last != block2->is_last) {
 431                 return false;
 432         }
 433         if(block1->length != block2->length) {
 434                 return false;
 435         }
 436         switch(block1->type) {
 437                 case FLAC__METADATA_TYPE_STREAMINFO:
 438                         return compare_block_data_streaminfo_(&block1->data.stream_info, &block2->data.stream_info);
 439                 case FLAC__METADATA_TYPE_PADDING:
 440                         return true; /* we don't compare the padding guts */
 441                 case FLAC__METADATA_TYPE_APPLICATION:
 442                         return compare_block_data_application_(&block1->data.application, &block2->data.application, block1->length);
 443                 case FLAC__METADATA_TYPE_SEEKTABLE:
 444                         return compare_block_data_seektable_(&block1->data.seek_table, &block2->data.seek_table);
 445                 case FLAC__METADATA_TYPE_VORBIS_COMMENT:
 446                         return compare_block_data_vorbiscomment_(&block1->data.vorbis_comment, &block2->data.vorbis_comment);
 447                 default:
 448                         FLAC__ASSERT(0);
 449                         return false;
 450         }
 451 }
 452
 453 FLAC_API FLAC__bool FLAC__metadata_object_application_set_data(FLAC__StreamMetadata *object, FLAC__byte *data, unsigned length, FLAC__bool copy)
 454 {
 455         FLAC__byte *save;
 456
 457         FLAC__ASSERT(0 != object);
 458         FLAC__ASSERT(object->type == FLAC__METADATA_TYPE_APPLICATION);
 459         FLAC__ASSERT((0 != data && length > 0) || (0 == data && length == 0 && copy == false));
 460
 461         save = object->data.application.data;
 462
 463         /* do the copy first so that if we fail we leave the object untouched */
 464         if(copy) {
 465                 if(!copy_bytes_(&object->data.application.data, data, length))
 466                         return false;
 467         }
 468         else {
 469                 object->data.application.data = data;
 470         }
 471
 472         if(0 != save)
 473                 free(save);
 474
 475         object->length = FLAC__STREAM_METADATA_APPLICATION_ID_LEN / 8 + length;
 476         return true;
 477 }
 478
 479 FLAC_API FLAC__bool FLAC__metadata_object_seektable_resize_points(FLAC__StreamMetadata *object, unsigned new_num_points)
 480 {
 481         FLAC__ASSERT(0 != object);
 482         FLAC__ASSERT(object->type == FLAC__METADATA_TYPE_SEEKTABLE);
 483
 484         if(0 == object->data.seek_table.points) {
 485                 FLAC__ASSERT(object->data.seek_table.num_points == 0);
 486                 if(0 == new_num_points)
 487                         return true;
 488                 else if(0 == (object->data.seek_table.points = seekpoint_array_new_(new_num_points)))
 489                         return false;
 490         }
 491         else {
 492                 const unsigned old_size = object->data.seek_table.num_points * sizeof(FLAC__StreamMetadata_SeekPoint);
 493                 const unsigned new_size = new_num_points * sizeof(FLAC__StreamMetadata_SeekPoint);
 494
 495                 FLAC__ASSERT(object->data.seek_table.num_points > 0);
 496
 497                 if(new_size == 0) {
 498                         free(object->data.seek_table.points);
 499                         object->data.seek_table.points = 0;
 500                 }
 501                 else if(0 == (object->data.seek_table.points = realloc(object->data.seek_table.points, new_size)))
 502                         return false;
 503
 504                 /* if growing, set new elements to placeholders */
 505                 if(new_size > old_size) {
 506                         unsigned i;
 507                         for(i = object->data.seek_table.num_points; i < new_num_points; i++) {
 508                                 object->data.seek_table.points[i].sample_number = FLAC__STREAM_METADATA_SEEKPOINT_PLACEHOLDER;
 509                                 object->data.seek_table.points[i].stream_offset = 0;
 510                                 object->data.seek_table.points[i].frame_samples = 0;
 511                         }
 512                 }
 513         }
 514
 515         object->data.seek_table.num_points = new_num_points;
 516
 517         seektable_calculate_length_(object);
 518         return true;
 519 }
 520
 521 FLAC_API void FLAC__metadata_object_seektable_set_point(FLAC__StreamMetadata *object, unsigned point_num, FLAC__StreamMetadata_SeekPoint point)
 522 {
 523         FLAC__ASSERT(0 != object);
 524         FLAC__ASSERT(object->type == FLAC__METADATA_TYPE_SEEKTABLE);
 525         FLAC__ASSERT(object->data.seek_table.num_points > point_num);
 526
 527         object->data.seek_table.points[point_num] = point;
 528 }
 529
 530 FLAC_API FLAC__bool FLAC__metadata_object_seektable_insert_point(FLAC__StreamMetadata *object, unsigned point_num, FLAC__StreamMetadata_SeekPoint point)
 531 {
 532         int i;
 533
 534         FLAC__ASSERT(0 != object);
 535         FLAC__ASSERT(object->type == FLAC__METADATA_TYPE_SEEKTABLE);
 536         FLAC__ASSERT(object->data.seek_table.num_points >= point_num);
 537
 538         if(!FLAC__metadata_object_seektable_resize_points(object, object->data.seek_table.num_points+1))
 539                 return false;
 540
 541         /* move all points >= point_num forward one space */
 542         for(i = (int)object->data.seek_table.num_points-1; i > (int)point_num; i--)
 543                 object->data.seek_table.points[i] = object->data.seek_table.points[i-1];
 544
 545         FLAC__metadata_object_seektable_set_point(object, point_num, point);
 546         seektable_calculate_length_(object);
 547         return true;
 548 }
 549
 550 FLAC_API FLAC__bool FLAC__metadata_object_seektable_delete_point(FLAC__StreamMetadata *object, unsigned point_num)
 551 {
 552         unsigned i;
 553
 554         FLAC__ASSERT(0 != object);
 555         FLAC__ASSERT(object->type == FLAC__METADATA_TYPE_SEEKTABLE);
 556         FLAC__ASSERT(object->data.seek_table.num_points > point_num);
 557
 558         /* move all points > point_num backward one space */
 559         for(i = point_num; i < object->data.seek_table.num_points-1; i++)
 560                 object->data.seek_table.points[i] = object->data.seek_table.points[i+1];
 561
 562         return FLAC__metadata_object_seektable_resize_points(object, object->data.seek_table.num_points-1);
 563 }
 564
 565 FLAC_API FLAC__bool FLAC__metadata_object_seektable_is_legal(const FLAC__StreamMetadata *object)
 566 {
 567         FLAC__ASSERT(0 != object);
 568         FLAC__ASSERT(object->type == FLAC__METADATA_TYPE_SEEKTABLE);
 569
 570         return FLAC__format_seektable_is_legal(&object->data.seek_table);
 571 }
 572
 573 FLAC_API FLAC__bool FLAC__metadata_object_seektable_template_append_placeholders(FLAC__StreamMetadata *object, unsigned num)
 574 {
 575         FLAC__ASSERT(0 != object);
 576         FLAC__ASSERT(object->type == FLAC__METADATA_TYPE_SEEKTABLE);
 577
 578         if(num > 0)
 579                 /* WATCHOUT: we rely on the fact that growing the array adds PLACEHOLDERS at the end */
 580                 return FLAC__metadata_object_seektable_resize_points(object, object->data.seek_table.num_points + num);
 581         else
 582                 return true;
 583 }
 584
 585 FLAC_API FLAC__bool FLAC__metadata_object_seektable_template_append_point(FLAC__StreamMetadata *object, FLAC__uint64 sample_number)
 586 {
 587         FLAC__StreamMetadata_SeekTable *seek_table;
 588
 589         FLAC__ASSERT(0 != object);
 590         FLAC__ASSERT(object->type == FLAC__METADATA_TYPE_SEEKTABLE);
 591
 592         seek_table = &object->data.seek_table;
 593
 594         if(!FLAC__metadata_object_seektable_resize_points(object, seek_table->num_points + 1))
 595                 return false;
 596
 597         seek_table->points[seek_table->num_points - 1].sample_number = sample_number;
 598         seek_table->points[seek_table->num_points - 1].stream_offset = 0;
 599         seek_table->points[seek_table->num_points - 1].frame_samples = 0;
 600
 601         return true;
 602 }
 603
 604 FLAC_API FLAC__bool FLAC__metadata_object_seektable_template_append_points(FLAC__StreamMetadata *object, FLAC__uint64 sample_numbers[], unsigned num)
 605 {
 606         FLAC__ASSERT(0 != object);
 607         FLAC__ASSERT(object->type == FLAC__METADATA_TYPE_SEEKTABLE);
 608         FLAC__ASSERT(0 != sample_numbers || num == 0);
 609
 610         if(num > 0) {
 611                 FLAC__StreamMetadata_SeekTable *seek_table = &object->data.seek_table;
 612                 unsigned i, j;
 613
 614                 i = seek_table->num_points;
 615
 616                 if(!FLAC__metadata_object_seektable_resize_points(object, seek_table->num_points + num))
 617                         return false;
 618
 619                 for(j = 0; j < num; i++, j++) {
 620                         seek_table->points[i].sample_number = sample_numbers[j];
 621                         seek_table->points[i].stream_offset = 0;
 622                         seek_table->points[i].frame_samples = 0;
 623                 }
 624         }
 625
 626         return true;
 627 }
 628
 629 FLAC_API FLAC__bool FLAC__metadata_object_seektable_template_append_spaced_points(FLAC__StreamMetadata *object, unsigned num, FLAC__uint64 total_samples)
 630 {
 631         FLAC__ASSERT(0 != object);
 632         FLAC__ASSERT(object->type == FLAC__METADATA_TYPE_SEEKTABLE);
 633         FLAC__ASSERT(total_samples > 0);
 634
 635         if(num > 0) {
 636                 FLAC__StreamMetadata_SeekTable *seek_table = &object->data.seek_table;
 637                 unsigned i, j;
 638
 639                 i = seek_table->num_points;
 640
 641                 if(!FLAC__metadata_object_seektable_resize_points(object, seek_table->num_points + num))
 642                         return false;
 643
 644                 for(j = 0; j < num; i++, j++) {
 645                         seek_table->points[i].sample_number = total_samples * (FLAC__uint64)j / (FLAC__uint64)num;
 646                         seek_table->points[i].stream_offset = 0;
 647                         seek_table->points[i].frame_samples = 0;
 648                 }
 649         }
 650
 651         return true;
 652 }
 653
 654 FLAC_API FLAC__bool FLAC__metadata_object_seektable_template_sort(FLAC__StreamMetadata *object, FLAC__bool compact)
 655 {
 656         unsigned unique;
 657
 658         FLAC__ASSERT(0 != object);
 659         FLAC__ASSERT(object->type == FLAC__METADATA_TYPE_SEEKTABLE);
 660
 661         unique = FLAC__format_seektable_sort(&object->data.seek_table);
 662
 663         return !compact || FLAC__metadata_object_seektable_resize_points(object, unique);
 664 }
 665
 666 FLAC_API FLAC__bool FLAC__metadata_object_vorbiscomment_set_vendor_string(FLAC__StreamMetadata *object, FLAC__StreamMetadata_VorbisComment_Entry entry, FLAC__bool copy)
 667 {
 668         return vorbiscomment_set_entry_(object, &object->data.vorbis_comment.vendor_string, &entry, copy);
 669 }
 670
 671 FLAC_API FLAC__bool FLAC__metadata_object_vorbiscomment_resize_comments(FLAC__StreamMetadata *object, unsigned new_num_comments)
 672 {
 673         FLAC__ASSERT(0 != object);
 674         FLAC__ASSERT(object->type == FLAC__METADATA_TYPE_VORBIS_COMMENT);
 675
 676         if(0 == object->data.vorbis_comment.comments) {
 677                 FLAC__ASSERT(object->data.vorbis_comment.num_comments == 0);
 678                 if(0 == new_num_comments)
 679                         return true;
 680                 else if(0 == (object->data.vorbis_comment.comments = vorbiscomment_entry_array_new_(new_num_comments)))
 681                         return false;
 682         }
 683         else {
 684                 const unsigned old_size = object->data.vorbis_comment.num_comments * sizeof(FLAC__StreamMetadata_VorbisComment_Entry);
 685                 const unsigned new_size = new_num_comments * sizeof(FLAC__StreamMetadata_VorbisComment_Entry);
 686
 687                 FLAC__ASSERT(object->data.vorbis_comment.num_comments > 0);
 688
 689                 /* if shrinking, free the truncated entries */
 690                 if(new_num_comments < object->data.vorbis_comment.num_comments) {
 691                         unsigned i;
 692                         for(i = new_num_comments; i < object->data.vorbis_comment.num_comments; i++)
 693                                 if(0 != object->data.vorbis_comment.comments[i].entry)
 694                                         free(object->data.vorbis_comment.comments[i].entry);
 695                 }
 696
 697                 if(new_size == 0) {
 698                         free(object->data.vorbis_comment.comments);
 699                         object->data.vorbis_comment.comments = 0;
 700                 }
 701                 else if(0 == (object->data.vorbis_comment.comments = realloc(object->data.vorbis_comment.comments, new_size)))
 702                         return false;
 703
 704                 /* if growing, zero all the length/pointers of new elements */
 705                 if(new_size > old_size)
 706                         memset(object->data.vorbis_comment.comments + object->data.vorbis_comment.num_comments, 0, new_size - old_size);
 707         }
 708
 709         object->data.vorbis_comment.num_comments = new_num_comments;
 710
 711         vorbiscomment_calculate_length_(object);
 712         return true;
 713 }
 714
 715 FLAC_API FLAC__bool FLAC__metadata_object_vorbiscomment_set_comment(FLAC__StreamMetadata *object, unsigned comment_num, FLAC__StreamMetadata_VorbisComment_Entry entry, FLAC__bool copy)
 716 {
 717         return vorbiscomment_set_entry_(object, &object->data.vorbis_comment.comments[comment_num], &entry, copy);
 718 }
 719
 720 FLAC_API FLAC__bool FLAC__metadata_object_vorbiscomment_insert_comment(FLAC__StreamMetadata *object, unsigned comment_num, FLAC__StreamMetadata_VorbisComment_Entry entry, FLAC__bool copy)
 721 {
 722         FLAC__StreamMetadata_VorbisComment *vc;
 723
 724         FLAC__ASSERT(0 != object);
 725         FLAC__ASSERT(object->type == FLAC__METADATA_TYPE_VORBIS_COMMENT);
 726         FLAC__ASSERT(object->data.vorbis_comment.num_comments >= comment_num);
 727
 728         vc = &object->data.vorbis_comment;
 729
 730         if(!FLAC__metadata_object_vorbiscomment_resize_comments(object, vc->num_comments+1))
 731                 return false;
 732
 733         /* move all comments >= comment_num forward one space */
 734         memmove(&vc->comments[comment_num+1], &vc->comments[comment_num], sizeof(FLAC__StreamMetadata_VorbisComment_Entry)*(vc->num_comments-1-comment_num));
 735         vc->comments[comment_num].length = 0;
 736         vc->comments[comment_num].entry = 0;
 737
 738         return FLAC__metadata_object_vorbiscomment_set_comment(object, comment_num, entry, copy);
 739 }
 740
 741 FLAC_API FLAC__bool FLAC__metadata_object_vorbiscomment_delete_comment(FLAC__StreamMetadata *object, unsigned comment_num)
 742 {
 743         FLAC__StreamMetadata_VorbisComment *vc;
 744
 745         FLAC__ASSERT(0 != object);
 746         FLAC__ASSERT(object->type == FLAC__METADATA_TYPE_VORBIS_COMMENT);
 747         FLAC__ASSERT(object->data.vorbis_comment.num_comments > comment_num);
 748
 749         vc = &object->data.vorbis_comment;
 750
 751         /* free the comment at comment_num */
 752         if(0 != vc->comments[comment_num].entry)
 753                 free(vc->comments[comment_num].entry);
 754
 755         /* move all comments > comment_num backward one space */
 756         memmove(&vc->comments[comment_num], &vc->comments[comment_num+1], sizeof(FLAC__StreamMetadata_VorbisComment_Entry)*(vc->num_comments-comment_num-1));
 757         vc->comments[vc->num_comments-1].length = 0;
 758         vc->comments[vc->num_comments-1].entry = 0;
 759
 760         return FLAC__metadata_object_vorbiscomment_resize_comments(object, vc->num_comments-1);
 761 }