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