src/libFLAC/metadata_iterators.c

   1 /* libFLAC - Free Lossless Audio Codec library
   2  * Copyright (C) 2001,2002,2003  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 <errno.h>
  21 #include <stdio.h>
  22 #include <stdlib.h>
  23 #include <string.h>
  24
  25 #if defined _MSC_VER || defined __MINGW32__
  26 #include <sys/utime.h> /* for utime() */
  27 #include <io.h> /* for chmod() */
  28 #else
  29 #include <sys/types.h> /* some flavors of BSD (like OS X) require this to get time_t */
  30 #include <utime.h> /* for utime() */
  31 #include <unistd.h> /* for chown(), unlink() */
  32 #endif
  33 #include <sys/stat.h> /* for stat(), maybe chmod() */
  34
  35 #include "private/metadata.h"
  36
  37 #include "FLAC/assert.h"
  38 #include "FLAC/file_decoder.h"
  39
  40 #ifdef max
  41 #undef max
  42 #endif
  43 #define max(a,b) ((a)>(b)?(a):(b))
  44 #ifdef min
  45 #undef min
  46 #endif
  47 #define min(a,b) ((a)<(b)?(a):(b))
  48
  49
  50 /****************************************************************************
  51  *
  52  * Local function declarations
  53  *
  54  ***************************************************************************/
  55
  56 static void pack_uint32_(FLAC__uint32 val, FLAC__byte *b, unsigned bytes);
  57 static void pack_uint32_little_endian_(FLAC__uint32 val, FLAC__byte *b, unsigned bytes);
  58 static void pack_uint64_(FLAC__uint64 val, FLAC__byte *b, unsigned bytes);
  59 static FLAC__uint32 unpack_uint32_(FLAC__byte *b, unsigned bytes);
  60 static FLAC__uint32 unpack_uint32_little_endian_(FLAC__byte *b, unsigned bytes);
  61 static FLAC__uint64 unpack_uint64_(FLAC__byte *b, unsigned bytes);
  62
  63 static FLAC__bool read_metadata_block_header_(FLAC__Metadata_SimpleIterator *iterator);
  64 static FLAC__bool read_metadata_block_data_(FLAC__Metadata_SimpleIterator *iterator, FLAC__StreamMetadata *block);
  65 static FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_streaminfo_(FILE *file, FLAC__StreamMetadata_StreamInfo *block);
  66 static FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_padding_(FILE *file, FLAC__StreamMetadata_Padding *block, unsigned block_length);
  67 static FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_application_(FILE *file, FLAC__StreamMetadata_Application *block, unsigned block_length);
  68 static FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_seektable_(FILE *file, FLAC__StreamMetadata_SeekTable *block, unsigned block_length);
  69 static FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_vorbis_comment_entry_(FILE *file, FLAC__StreamMetadata_VorbisComment_Entry *entry);
  70 static FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_vorbis_comment_(FILE *file, FLAC__StreamMetadata_VorbisComment *block);
  71 static FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_cuesheet_track_(FILE *file, FLAC__StreamMetadata_CueSheet_Track *track);
  72 static FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_cuesheet_(FILE *file, FLAC__StreamMetadata_CueSheet *block);
  73 static FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_unknown_(FILE *file, FLAC__StreamMetadata_Unknown *block, unsigned block_length);
  74
  75 static FLAC__bool write_metadata_block_header_(FILE *file, FLAC__Metadata_SimpleIteratorStatus *status, const FLAC__StreamMetadata *block);
  76 static FLAC__bool write_metadata_block_data_(FILE *file, FLAC__Metadata_SimpleIteratorStatus *status, const FLAC__StreamMetadata *block);
  77 static FLAC__Metadata_SimpleIteratorStatus write_metadata_block_data_streaminfo_(FILE *file, const FLAC__StreamMetadata_StreamInfo *block);
  78 static FLAC__Metadata_SimpleIteratorStatus write_metadata_block_data_padding_(FILE *file, const FLAC__StreamMetadata_Padding *block, unsigned block_length);
  79 static FLAC__Metadata_SimpleIteratorStatus write_metadata_block_data_application_(FILE *file, const FLAC__StreamMetadata_Application *block, unsigned block_length);
  80 static FLAC__Metadata_SimpleIteratorStatus write_metadata_block_data_seektable_(FILE *file, const FLAC__StreamMetadata_SeekTable *block);
  81 static FLAC__Metadata_SimpleIteratorStatus write_metadata_block_data_vorbis_comment_(FILE *file, const FLAC__StreamMetadata_VorbisComment *block);
  82 static FLAC__Metadata_SimpleIteratorStatus write_metadata_block_data_cuesheet_(FILE *file, const FLAC__StreamMetadata_CueSheet *block);
  83 static FLAC__Metadata_SimpleIteratorStatus write_metadata_block_data_unknown_(FILE *file, const FLAC__StreamMetadata_Unknown *block, unsigned block_length);
  84 static FLAC__bool write_metadata_block_stationary_(FLAC__Metadata_SimpleIterator *iterator, const FLAC__StreamMetadata *block);
  85 static FLAC__bool write_metadata_block_stationary_with_padding_(FLAC__Metadata_SimpleIterator *iterator, FLAC__StreamMetadata *block, unsigned padding_length, FLAC__bool padding_is_last);
  86 static FLAC__bool rewrite_whole_file_(FLAC__Metadata_SimpleIterator *iterator, FLAC__StreamMetadata *block, FLAC__bool append);
  87
  88 static FLAC__bool chain_rewrite_chain_(FLAC__Metadata_Chain *chain);
  89 static FLAC__bool chain_rewrite_file_(FLAC__Metadata_Chain *chain, const char *tempfile_path_prefix);
  90
  91 static void simple_iterator_push_(FLAC__Metadata_SimpleIterator *iterator);
  92 static FLAC__bool simple_iterator_pop_(FLAC__Metadata_SimpleIterator *iterator);
  93
  94 /* return 0 if OK, 1 if read error, 2 if not a FLAC file */
  95 static unsigned seek_to_first_metadata_block_(FILE *f);
  96
  97 static FLAC__bool simple_iterator_copy_file_prefix_(FLAC__Metadata_SimpleIterator *iterator, FILE **tempfile, char **tempfilename, FLAC__bool append);
  98 static FLAC__bool simple_iterator_copy_file_postfix_(FLAC__Metadata_SimpleIterator *iterator, FILE **tempfile, char **tempfilename, int fixup_is_last_code, long fixup_is_last_flag_offset, FLAC__bool backup);
  99
 100 static FLAC__bool copy_n_bytes_from_file_(FILE *file, FILE *tempfile, unsigned bytes/*@@@ 4G limit*/, FLAC__Metadata_SimpleIteratorStatus *status);
 101 static FLAC__bool copy_remaining_bytes_from_file_(FILE *file, FILE *tempfile, FLAC__Metadata_SimpleIteratorStatus *status);
 102
 103 static FLAC__bool open_tempfile_(const char *filename, const char *tempfile_path_prefix, FILE **tempfile, char **tempfilename, FLAC__Metadata_SimpleIteratorStatus *status);
 104 static FLAC__bool transport_tempfile_(const char *filename, FILE **tempfile, char **tempfilename, FLAC__Metadata_SimpleIteratorStatus *status);
 105 static void cleanup_tempfile_(FILE **tempfile, char **tempfilename);
 106
 107 static FLAC__bool get_file_stats_(const char *filename, struct stat *stats);
 108 static void set_file_stats_(const char *filename, struct stat *stats);
 109
 110 static FLAC__Metadata_ChainStatus get_equivalent_status_(FLAC__Metadata_SimpleIteratorStatus status);
 111
 112
 113 #ifdef FLAC__VALGRIND_TESTING
 114 static size_t local__fwrite(const void *ptr, size_t size, size_t nmemb, FILE *stream)
 115 {
 116         size_t ret = fwrite(ptr, size, nmemb, stream);
 117         if(!ferror(stream))
 118                 fflush(stream);
 119         return ret;
 120 }
 121 #else
 122 #define local__fwrite fwrite
 123 #endif
 124
 125 /****************************************************************************
 126  *
 127  * Level 0 implementation
 128  *
 129  ***************************************************************************/
 130
 131 static FLAC__StreamDecoderWriteStatus write_callback_(const FLAC__FileDecoder *decoder, const FLAC__Frame *frame, const FLAC__int32 * const buffer[], void *client_data);
 132 static void metadata_callback_(const FLAC__FileDecoder *decoder, const FLAC__StreamMetadata *metadata, void *client_data);
 133 static void error_callback_(const FLAC__FileDecoder *decoder, FLAC__StreamDecoderErrorStatus status, void *client_data);
 134
 135 typedef struct {
 136         FLAC__bool got_error;
 137         FLAC__bool got_streaminfo;
 138         FLAC__StreamMetadata *streaminfo;
 139 } level0_client_data;
 140
 141 FLAC_API FLAC__bool FLAC__metadata_get_streaminfo(const char *filename, FLAC__StreamMetadata *streaminfo)
 142 {
 143         level0_client_data cd;
 144         FLAC__FileDecoder *decoder;
 145
 146         FLAC__ASSERT(0 != filename);
 147         FLAC__ASSERT(0 != streaminfo);
 148
 149         decoder = FLAC__file_decoder_new();
 150
 151         if(0 == decoder)
 152                 return false;
 153
 154         cd.got_error = false;
 155         cd.got_streaminfo = false;
 156         cd.streaminfo = streaminfo;
 157
 158         FLAC__file_decoder_set_md5_checking(decoder, false);
 159         FLAC__file_decoder_set_filename(decoder, filename);
 160         FLAC__file_decoder_set_metadata_ignore_all(decoder);
 161         FLAC__file_decoder_set_metadata_respond(decoder, FLAC__METADATA_TYPE_STREAMINFO);
 162         FLAC__file_decoder_set_write_callback(decoder, write_callback_);
 163         FLAC__file_decoder_set_metadata_callback(decoder, metadata_callback_);
 164         FLAC__file_decoder_set_error_callback(decoder, error_callback_);
 165         FLAC__file_decoder_set_client_data(decoder, &cd);
 166
 167         if(FLAC__file_decoder_init(decoder) != FLAC__FILE_DECODER_OK || cd.got_error) {
 168                 FLAC__file_decoder_finish(decoder);
 169                 FLAC__file_decoder_delete(decoder);
 170                 return false;
 171         }
 172
 173         /* the first thing decoded must be the STREAMINFO block: */
 174         if(!FLAC__file_decoder_process_until_end_of_metadata(decoder) || cd.got_error) {
 175                 FLAC__file_decoder_finish(decoder);
 176                 FLAC__file_decoder_delete(decoder);
 177                 return false;
 178         }
 179
 180         FLAC__file_decoder_finish(decoder);
 181         FLAC__file_decoder_delete(decoder);
 182
 183         return !cd.got_error && cd.got_streaminfo;
 184 }
 185
 186 FLAC__StreamDecoderWriteStatus write_callback_(const FLAC__FileDecoder *decoder, const FLAC__Frame *frame, const FLAC__int32 * const buffer[], void *client_data)
 187 {
 188         (void)decoder, (void)frame, (void)buffer, (void)client_data;
 189
 190         return FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE;
 191 }
 192
 193 void metadata_callback_(const FLAC__FileDecoder *decoder, const FLAC__StreamMetadata *metadata, void *client_data)
 194 {
 195         level0_client_data *cd = (level0_client_data *)client_data;
 196         (void)decoder;
 197
 198         if(metadata->type == FLAC__METADATA_TYPE_STREAMINFO && 0 != cd->streaminfo) {
 199                 *(cd->streaminfo) = *metadata;
 200                 cd->got_streaminfo = true;
 201         }
 202 }
 203
 204 void error_callback_(const FLAC__FileDecoder *decoder, FLAC__StreamDecoderErrorStatus status, void *client_data)
 205 {
 206         level0_client_data *cd = (level0_client_data *)client_data;
 207         (void)decoder;
 208
 209         if(status != FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC)
 210                 cd->got_error = true;
 211 }
 212
 213
 214 /****************************************************************************
 215  *
 216  * Level 1 implementation
 217  *
 218  ***************************************************************************/
 219
 220 #define SIMPLE_ITERATOR_MAX_PUSH_DEPTH (1+4)
 221 /* 1 for initial offset, +4 for our own personal use */
 222
 223 struct FLAC__Metadata_SimpleIterator {
 224         FILE *file;
 225         char *filename, *tempfile_path_prefix;
 226         struct stat stats;
 227         FLAC__bool has_stats;
 228         FLAC__bool is_writable;
 229         FLAC__Metadata_SimpleIteratorStatus status;
 230         /*@@@ 2G limits here because of the offset type: */
 231         long offset[SIMPLE_ITERATOR_MAX_PUSH_DEPTH];
 232         long first_offset; /* this is the offset to the STREAMINFO block */
 233         unsigned depth;
 234         /* this is the metadata block header of the current block we are pointing to: */
 235         FLAC__bool is_last;
 236         FLAC__MetadataType type;
 237         unsigned length;
 238 };
 239
 240 FLAC_API const char * const FLAC__Metadata_SimpleIteratorStatusString[] = {
 241         "FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK",
 242         "FLAC__METADATA_SIMPLE_ITERATOR_STATUS_ILLEGAL_INPUT",
 243         "FLAC__METADATA_SIMPLE_ITERATOR_STATUS_ERROR_OPENING_FILE",
 244         "FLAC__METADATA_SIMPLE_ITERATOR_STATUS_NOT_A_FLAC_FILE",
 245         "FLAC__METADATA_SIMPLE_ITERATOR_STATUS_NOT_WRITABLE",
 246         "FLAC__METADATA_SIMPLE_ITERATOR_STATUS_BAD_METADATA",
 247         "FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR",
 248         "FLAC__METADATA_SIMPLE_ITERATOR_STATUS_SEEK_ERROR",
 249         "FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR",
 250         "FLAC__METADATA_SIMPLE_ITERATOR_STATUS_RENAME_ERROR",
 251         "FLAC__METADATA_SIMPLE_ITERATOR_STATUS_UNLINK_ERROR",
 252         "FLAC__METADATA_SIMPLE_ITERATOR_STATUS_MEMORY_ALLOCATION_ERROR",
 253         "FLAC__METADATA_SIMPLE_ITERATOR_STATUS_INTERNAL_ERROR"
 254 };
 255
 256
 257 FLAC_API FLAC__Metadata_SimpleIterator *FLAC__metadata_simple_iterator_new()
 258 {
 259         FLAC__Metadata_SimpleIterator *iterator = (FLAC__Metadata_SimpleIterator*)calloc(1, sizeof(FLAC__Metadata_SimpleIterator));
 260
 261         if(0 != iterator) {
 262                 iterator->file = 0;
 263                 iterator->filename = 0;
 264                 iterator->tempfile_path_prefix = 0;
 265                 iterator->has_stats = false;
 266                 iterator->is_writable = false;
 267                 iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK;
 268                 iterator->first_offset = iterator->offset[0] = -1;
 269                 iterator->depth = 0;
 270         }
 271
 272         return iterator;
 273 }
 274
 275 static void simple_iterator_free_guts_(FLAC__Metadata_SimpleIterator *iterator)
 276 {
 277         FLAC__ASSERT(0 != iterator);
 278
 279         if(0 != iterator->file) {
 280                 fclose(iterator->file);
 281                 iterator->file = 0;
 282                 if(iterator->has_stats)
 283                         set_file_stats_(iterator->filename, &iterator->stats);
 284         }
 285         if(0 != iterator->filename) {
 286                 free(iterator->filename);
 287                 iterator->filename = 0;
 288         }
 289         if(0 != iterator->tempfile_path_prefix) {
 290                 free(iterator->tempfile_path_prefix);
 291                 iterator->tempfile_path_prefix = 0;
 292         }
 293 }
 294
 295 FLAC_API void FLAC__metadata_simple_iterator_delete(FLAC__Metadata_SimpleIterator *iterator)
 296 {
 297         FLAC__ASSERT(0 != iterator);
 298
 299         simple_iterator_free_guts_(iterator);
 300         free(iterator);
 301 }
 302
 303 FLAC_API FLAC__Metadata_SimpleIteratorStatus FLAC__metadata_simple_iterator_status(FLAC__Metadata_SimpleIterator *iterator)
 304 {
 305         FLAC__Metadata_SimpleIteratorStatus status;
 306
 307         FLAC__ASSERT(0 != iterator);
 308
 309         status = iterator->status;
 310         iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK;
 311         return status;
 312 }
 313
 314 static FLAC__bool simple_iterator_prime_input_(FLAC__Metadata_SimpleIterator *iterator, FLAC__bool read_only)
 315 {
 316         unsigned ret;
 317
 318         FLAC__ASSERT(0 != iterator);
 319
 320         if(read_only || 0 == (iterator->file = fopen(iterator->filename, "r+b"))) {
 321                 iterator->is_writable = false;
 322                 if(read_only || errno == EACCES) {
 323                         if(0 == (iterator->file = fopen(iterator->filename, "rb"))) {
 324                                 iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_ERROR_OPENING_FILE;
 325                                 return false;
 326                         }
 327                 }
 328                 else {
 329                         iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_ERROR_OPENING_FILE;
 330                         return false;
 331                 }
 332         }
 333         else {
 334                 iterator->is_writable = true;
 335         }
 336
 337         ret = seek_to_first_metadata_block_(iterator->file);
 338         switch(ret) {
 339                 case 0:
 340                         iterator->depth = 0;
 341                         iterator->first_offset = iterator->offset[iterator->depth] = ftell(iterator->file);
 342                         return read_metadata_block_header_(iterator);
 343                 case 1:
 344                         iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
 345                         return false;
 346                 case 2:
 347                         iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_NOT_A_FLAC_FILE;
 348                         return false;
 349                 default:
 350                         FLAC__ASSERT(0);
 351                         return false;
 352         }
 353 }
 354
 355 #if 0
 356 @@@ If we decide to finish implementing this, put this comment back in metadata.h
 357 /*
 358  * The 'tempfile_path_prefix' allows you to specify a directory where
 359  * tempfiles should go.  Remember that if your metadata edits cause the
 360  * FLAC file to grow, the entire file will have to be rewritten.  If
 361  * 'tempfile_path_prefix' is NULL, the temp file will be written in the
 362  * same directory as the original FLAC file.  This makes replacing the
 363  * original with the tempfile fast but requires extra space in the same
 364  * partition for the tempfile.  If space is a problem, you can pass a
 365  * directory name belonging to a different partition in
 366  * 'tempfile_path_prefix'.  Note that you should use the forward slash
 367  * '/' as the directory separator.  A trailing slash is not needed; it
 368  * will be added automatically.
 369  */
 370 FLAC__bool FLAC__metadata_simple_iterator_init(FLAC__Metadata_SimpleIterator *iterator, const char *filename, FLAC__bool preserve_file_stats, const char *tempfile_path_prefix);
 371 #endif
 372
 373 FLAC_API FLAC__bool FLAC__metadata_simple_iterator_init(FLAC__Metadata_SimpleIterator *iterator, const char *filename, FLAC__bool read_only, FLAC__bool preserve_file_stats)
 374 {
 375         const char *tempfile_path_prefix = 0; /*@@@ search for comments near 'rename(...)' for what it will take to finish implementing this */
 376
 377         FLAC__ASSERT(0 != iterator);
 378         FLAC__ASSERT(0 != filename);
 379
 380         simple_iterator_free_guts_(iterator);
 381
 382         if(!read_only && preserve_file_stats)
 383                 iterator->has_stats = get_file_stats_(filename, &iterator->stats);
 384
 385         if(0 == (iterator->filename = strdup(filename))) {
 386                 iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_MEMORY_ALLOCATION_ERROR;
 387                 return false;
 388         }
 389         if(0 != tempfile_path_prefix && 0 == (iterator->tempfile_path_prefix = strdup(tempfile_path_prefix))) {
 390                 iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_MEMORY_ALLOCATION_ERROR;
 391                 return false;
 392         }
 393
 394         return simple_iterator_prime_input_(iterator, read_only);
 395 }
 396
 397 FLAC_API FLAC__bool FLAC__metadata_simple_iterator_is_writable(const FLAC__Metadata_SimpleIterator *iterator)
 398 {
 399         FLAC__ASSERT(0 != iterator);
 400         FLAC__ASSERT(0 != iterator->file);
 401
 402         return iterator->is_writable;
 403 }
 404
 405 FLAC_API FLAC__bool FLAC__metadata_simple_iterator_next(FLAC__Metadata_SimpleIterator *iterator)
 406 {
 407         FLAC__ASSERT(0 != iterator);
 408         FLAC__ASSERT(0 != iterator->file);
 409
 410         if(iterator->is_last)
 411                 return false;
 412
 413         if(0 != fseek(iterator->file, iterator->length, SEEK_CUR)) {
 414                 iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_SEEK_ERROR;
 415                 return false;
 416         }
 417
 418         iterator->offset[iterator->depth] = ftell(iterator->file);
 419
 420         return read_metadata_block_header_(iterator);
 421 }
 422
 423 FLAC_API FLAC__bool FLAC__metadata_simple_iterator_prev(FLAC__Metadata_SimpleIterator *iterator)
 424 {
 425         long this_offset;
 426
 427         FLAC__ASSERT(0 != iterator);
 428         FLAC__ASSERT(0 != iterator->file);
 429
 430         if(iterator->offset[iterator->depth] == iterator->first_offset)
 431                 return false;
 432
 433         if(0 != fseek(iterator->file, iterator->first_offset, SEEK_SET)) {
 434                 iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_SEEK_ERROR;
 435                 return false;
 436         }
 437         this_offset = iterator->first_offset;
 438         if(!read_metadata_block_header_(iterator))
 439                 return false;
 440
 441         /* we ignore any error from ftell() and catch it in fseek() */
 442         while(ftell(iterator->file) + (long)iterator->length < iterator->offset[iterator->depth]) {
 443                 if(0 != fseek(iterator->file, iterator->length, SEEK_CUR)) {
 444                         iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_SEEK_ERROR;
 445                         return false;
 446                 }
 447                 this_offset = ftell(iterator->file);
 448                 if(!read_metadata_block_header_(iterator))
 449                         return false;
 450         }
 451
 452         iterator->offset[iterator->depth] = this_offset;
 453
 454         return true;
 455 }
 456
 457 FLAC_API FLAC__MetadataType FLAC__metadata_simple_iterator_get_block_type(const FLAC__Metadata_SimpleIterator *iterator)
 458 {
 459         FLAC__ASSERT(0 != iterator);
 460         FLAC__ASSERT(0 != iterator->file);
 461
 462         return iterator->type;
 463 }
 464
 465 FLAC_API FLAC__StreamMetadata *FLAC__metadata_simple_iterator_get_block(FLAC__Metadata_SimpleIterator *iterator)
 466 {
 467         FLAC__StreamMetadata *block = FLAC__metadata_object_new(iterator->type);
 468
 469         FLAC__ASSERT(0 != iterator);
 470         FLAC__ASSERT(0 != iterator->file);
 471
 472         if(0 != block) {
 473                 block->is_last = iterator->is_last;
 474                 block->length = iterator->length;
 475
 476                 if(!read_metadata_block_data_(iterator, block)) {
 477                         FLAC__metadata_object_delete(block);
 478                         return 0;
 479                 }
 480
 481                 /* back up to the beginning of the block data to stay consistent */
 482                 if(0 != fseek(iterator->file, iterator->offset[iterator->depth] + FLAC__STREAM_METADATA_HEADER_LENGTH, SEEK_SET)) {
 483                         iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_SEEK_ERROR;
 484                         FLAC__metadata_object_delete(block);
 485                         return 0;
 486                 }
 487         }
 488         else
 489                 iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_MEMORY_ALLOCATION_ERROR;
 490
 491         return block;
 492 }
 493
 494 FLAC_API FLAC__bool FLAC__metadata_simple_iterator_set_block(FLAC__Metadata_SimpleIterator *iterator, FLAC__StreamMetadata *block, FLAC__bool use_padding)
 495 {
 496         FLAC__ASSERT_DECLARATION(long debug_target_offset = iterator->offset[iterator->depth];)
 497         FLAC__bool ret;
 498
 499         FLAC__ASSERT(0 != iterator);
 500         FLAC__ASSERT(0 != iterator->file);
 501         FLAC__ASSERT(0 != block);
 502
 503         if(!iterator->is_writable) {
 504                 iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_NOT_WRITABLE;
 505                 return false;
 506         }
 507
 508         if(iterator->type == FLAC__METADATA_TYPE_STREAMINFO || block->type == FLAC__METADATA_TYPE_STREAMINFO) {
 509                 if(iterator->type != block->type) {
 510                         iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_ILLEGAL_INPUT;
 511                         return false;
 512                 }
 513         }
 514
 515         block->is_last = iterator->is_last;
 516
 517         if(iterator->length == block->length)
 518                 return write_metadata_block_stationary_(iterator, block);
 519         else if(iterator->length > block->length) {
 520                 if(use_padding && iterator->length >= FLAC__STREAM_METADATA_HEADER_LENGTH + block->length) {
 521                         ret = write_metadata_block_stationary_with_padding_(iterator, block, iterator->length - FLAC__STREAM_METADATA_HEADER_LENGTH - block->length, block->is_last);
 522                         FLAC__ASSERT(!ret || iterator->offset[iterator->depth] == debug_target_offset);
 523                         FLAC__ASSERT(!ret || ftell(iterator->file) == debug_target_offset + (long)FLAC__STREAM_METADATA_HEADER_LENGTH);
 524                         return ret;
 525                 }
 526                 else {
 527                         ret = rewrite_whole_file_(iterator, block, /*append=*/false);
 528                         FLAC__ASSERT(!ret || iterator->offset[iterator->depth] == debug_target_offset);
 529                         FLAC__ASSERT(!ret || ftell(iterator->file) == debug_target_offset + (long)FLAC__STREAM_METADATA_HEADER_LENGTH);
 530                         return ret;
 531                 }
 532         }
 533         else /* iterator->length < block->length */ {
 534                 unsigned padding_leftover = 0;
 535                 FLAC__bool padding_is_last = false;
 536                 if(use_padding) {
 537                         /* first see if we can even use padding */
 538                         if(iterator->is_last) {
 539                                 use_padding = false;
 540                         }
 541                         else {
 542                                 const unsigned extra_padding_bytes_required = block->length - iterator->length;
 543                                 simple_iterator_push_(iterator);
 544                                 if(!FLAC__metadata_simple_iterator_next(iterator)) {
 545                                         (void)simple_iterator_pop_(iterator);
 546                                         return false;
 547                                 }
 548                                 if(iterator->type != FLAC__METADATA_TYPE_PADDING) {
 549                                         use_padding = false;
 550                                 }
 551                                 else {
 552                                         if(FLAC__STREAM_METADATA_HEADER_LENGTH + iterator->length == extra_padding_bytes_required) {
 553                                                 padding_leftover = 0;
 554                                                 block->is_last = iterator->is_last;
 555                                         }
 556                                         else if(iterator->length < extra_padding_bytes_required)
 557                                                 use_padding = false;
 558                                         else {
 559                                                 padding_leftover = FLAC__STREAM_METADATA_HEADER_LENGTH + iterator->length - extra_padding_bytes_required;
 560                                                 padding_is_last = iterator->is_last;
 561                                                 block->is_last = false;
 562                                         }
 563                                 }
 564                                 if(!simple_iterator_pop_(iterator))
 565                                         return false;
 566                         }
 567                 }
 568                 if(use_padding) {
 569                         if(padding_leftover == 0) {
 570                                 ret = write_metadata_block_stationary_(iterator, block);
 571                                 FLAC__ASSERT(!ret || iterator->offset[iterator->depth] == debug_target_offset);
 572                                 FLAC__ASSERT(!ret || ftell(iterator->file) == debug_target_offset + (long)FLAC__STREAM_METADATA_HEADER_LENGTH);
 573                                 return ret;
 574                         }
 575                         else {
 576                                 FLAC__ASSERT(padding_leftover >= FLAC__STREAM_METADATA_HEADER_LENGTH);
 577                                 ret = write_metadata_block_stationary_with_padding_(iterator, block, padding_leftover - FLAC__STREAM_METADATA_HEADER_LENGTH, padding_is_last);
 578                                 FLAC__ASSERT(!ret || iterator->offset[iterator->depth] == debug_target_offset);
 579                                 FLAC__ASSERT(!ret || ftell(iterator->file) == debug_target_offset + (long)FLAC__STREAM_METADATA_HEADER_LENGTH);
 580                                 return ret;
 581                         }
 582                 }
 583                 else {
 584                         ret = rewrite_whole_file_(iterator, block, /*append=*/false);
 585                         FLAC__ASSERT(!ret || iterator->offset[iterator->depth] == debug_target_offset);
 586                         FLAC__ASSERT(!ret || ftell(iterator->file) == debug_target_offset + (long)FLAC__STREAM_METADATA_HEADER_LENGTH);
 587                         return ret;
 588                 }
 589         }
 590 }
 591
 592 FLAC_API FLAC__bool FLAC__metadata_simple_iterator_insert_block_after(FLAC__Metadata_SimpleIterator *iterator, FLAC__StreamMetadata *block, FLAC__bool use_padding)
 593 {
 594         unsigned padding_leftover = 0;
 595         FLAC__bool padding_is_last = false;
 596
 597         FLAC__ASSERT_DECLARATION(long debug_target_offset = iterator->offset[iterator->depth] + FLAC__STREAM_METADATA_HEADER_LENGTH + iterator->length;)
 598         FLAC__bool ret;
 599
 600         FLAC__ASSERT(0 != iterator);
 601         FLAC__ASSERT(0 != iterator->file);
 602         FLAC__ASSERT(0 != block);
 603
 604         if(!iterator->is_writable)
 605                 return false;
 606
 607         if(block->type == FLAC__METADATA_TYPE_STREAMINFO) {
 608                 iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_ILLEGAL_INPUT;
 609                 return false;
 610         }
 611
 612         block->is_last = iterator->is_last;
 613
 614         if(use_padding) {
 615                 /* first see if we can even use padding */
 616                 if(iterator->is_last) {
 617                         use_padding = false;
 618                 }
 619                 else {
 620                         simple_iterator_push_(iterator);
 621                         if(!FLAC__metadata_simple_iterator_next(iterator)) {
 622                                 (void)simple_iterator_pop_(iterator);
 623                                 return false;
 624                         }
 625                         if(iterator->type != FLAC__METADATA_TYPE_PADDING) {
 626                                 use_padding = false;
 627                         }
 628                         else {
 629                                 if(iterator->length == block->length) {
 630                                         padding_leftover = 0;
 631                                         block->is_last = iterator->is_last;
 632                                 }
 633                                 else if(iterator->length < FLAC__STREAM_METADATA_HEADER_LENGTH + block->length)
 634                                         use_padding = false;
 635                                 else {
 636                                         padding_leftover = iterator->length - block->length;
 637                                         padding_is_last = iterator->is_last;
 638                                         block->is_last = false;
 639                                 }
 640                         }
 641                         if(!simple_iterator_pop_(iterator))
 642                                 return false;
 643                 }
 644         }
 645         if(use_padding) {
 646                 /* move to the next block, which is suitable padding */
 647                 if(!FLAC__metadata_simple_iterator_next(iterator))
 648                         return false;
 649                 if(padding_leftover == 0) {
 650                         ret = write_metadata_block_stationary_(iterator, block);
 651                         FLAC__ASSERT(iterator->offset[iterator->depth] == debug_target_offset);
 652                         FLAC__ASSERT(ftell(iterator->file) == debug_target_offset + (long)FLAC__STREAM_METADATA_HEADER_LENGTH);
 653                         return ret;
 654                 }
 655                 else {
 656                         FLAC__ASSERT(padding_leftover >= FLAC__STREAM_METADATA_HEADER_LENGTH);
 657                         ret = write_metadata_block_stationary_with_padding_(iterator, block, padding_leftover - FLAC__STREAM_METADATA_HEADER_LENGTH, padding_is_last);
 658                         FLAC__ASSERT(iterator->offset[iterator->depth] == debug_target_offset);
 659                         FLAC__ASSERT(ftell(iterator->file) == debug_target_offset + (long)FLAC__STREAM_METADATA_HEADER_LENGTH);
 660                         return ret;
 661                 }
 662         }
 663         else {
 664                 ret = rewrite_whole_file_(iterator, block, /*append=*/true);
 665                 FLAC__ASSERT(iterator->offset[iterator->depth] == debug_target_offset);
 666                 FLAC__ASSERT(ftell(iterator->file) == debug_target_offset + (long)FLAC__STREAM_METADATA_HEADER_LENGTH);
 667                 return ret;
 668         }
 669 }
 670
 671 FLAC_API FLAC__bool FLAC__metadata_simple_iterator_delete_block(FLAC__Metadata_SimpleIterator *iterator, FLAC__bool use_padding)
 672 {
 673         FLAC__ASSERT_DECLARATION(long debug_target_offset = iterator->offset[iterator->depth];)
 674         FLAC__bool ret;
 675
 676         if(iterator->type == FLAC__METADATA_TYPE_STREAMINFO) {
 677                 iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_ILLEGAL_INPUT;
 678                 return false;
 679         }
 680
 681         if(use_padding) {
 682                 FLAC__StreamMetadata *padding = FLAC__metadata_object_new(FLAC__METADATA_TYPE_PADDING);
 683                 if(0 == padding) {
 684                         iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_MEMORY_ALLOCATION_ERROR;
 685                         return false;
 686                 }
 687                 padding->length = iterator->length;
 688                 if(!FLAC__metadata_simple_iterator_set_block(iterator, padding, false)) {
 689                         FLAC__metadata_object_delete(padding);
 690                         return false;
 691                 }
 692                 FLAC__metadata_object_delete(padding);
 693                 if(!FLAC__metadata_simple_iterator_prev(iterator))
 694                         return false;
 695                 FLAC__ASSERT(iterator->offset[iterator->depth] + (long)FLAC__STREAM_METADATA_HEADER_LENGTH + (long)iterator->length == debug_target_offset);
 696                 FLAC__ASSERT(ftell(iterator->file) + (long)iterator->length == debug_target_offset);
 697                 return true;
 698         }
 699         else {
 700                 ret = rewrite_whole_file_(iterator, 0, /*append=*/false);
 701                 FLAC__ASSERT(iterator->offset[iterator->depth] + (long)FLAC__STREAM_METADATA_HEADER_LENGTH + (long)iterator->length == debug_target_offset);
 702                 FLAC__ASSERT(ftell(iterator->file) + (long)iterator->length == debug_target_offset);
 703                 return ret;
 704         }
 705 }
 706
 707
 708
 709 /****************************************************************************
 710  *
 711  * Level 2 implementation
 712  *
 713  ***************************************************************************/
 714
 715
 716 typedef struct FLAC__Metadata_Node {
 717         FLAC__StreamMetadata *data;
 718         struct FLAC__Metadata_Node *prev, *next;
 719 } FLAC__Metadata_Node;
 720
 721 struct FLAC__Metadata_Chain {
 722         char *filename;
 723         FLAC__Metadata_Node *head;
 724         FLAC__Metadata_Node *tail;
 725         unsigned nodes;
 726         FLAC__Metadata_ChainStatus status;
 727         long first_offset, last_offset; /*@@@ 2G limit */
 728         /*
 729          * This is the length of the chain initially read from the FLAC file.
 730          * it is used to compare against the current length to decide whether
 731          * or not the whole file has to be rewritten.
 732          */
 733         unsigned initial_length; /*@@@ 4G limit */
 734 };
 735
 736 struct FLAC__Metadata_Iterator {
 737         FLAC__Metadata_Chain *chain;
 738         FLAC__Metadata_Node *current;
 739 };
 740
 741 FLAC_API const char * const FLAC__Metadata_ChainStatusString[] = {
 742         "FLAC__METADATA_CHAIN_STATUS_OK",
 743         "FLAC__METADATA_CHAIN_STATUS_ILLEGAL_INPUT",
 744         "FLAC__METADATA_CHAIN_STATUS_ERROR_OPENING_FILE",
 745         "FLAC__METADATA_CHAIN_STATUS_NOT_A_FLAC_FILE",
 746         "FLAC__METADATA_CHAIN_STATUS_NOT_WRITABLE",
 747         "FLAC__METADATA_CHAIN_STATUS_BAD_METADATA",
 748         "FLAC__METADATA_CHAIN_STATUS_READ_ERROR",
 749         "FLAC__METADATA_CHAIN_STATUS_SEEK_ERROR",
 750         "FLAC__METADATA_CHAIN_STATUS_WRITE_ERROR",
 751         "FLAC__METADATA_CHAIN_STATUS_RENAME_ERROR",
 752         "FLAC__METADATA_CHAIN_STATUS_UNLINK_ERROR",
 753         "FLAC__METADATA_CHAIN_STATUS_MEMORY_ALLOCATION_ERROR",
 754         "FLAC__METADATA_CHAIN_STATUS_INTERNAL_ERROR"
 755 };
 756
 757
 758 static FLAC__Metadata_Node *node_new_()
 759 {
 760         return (FLAC__Metadata_Node*)calloc(1, sizeof(FLAC__Metadata_Node));
 761 }
 762
 763 static void node_delete_(FLAC__Metadata_Node *node)
 764 {
 765         FLAC__ASSERT(0 != node);
 766         if(0 != node->data)
 767                 FLAC__metadata_object_delete(node->data);
 768         free(node);
 769 }
 770
 771 static void chain_append_node_(FLAC__Metadata_Chain *chain, FLAC__Metadata_Node *node)
 772 {
 773         FLAC__ASSERT(0 != chain);
 774         FLAC__ASSERT(0 != node);
 775         FLAC__ASSERT(0 != node->data);
 776
 777         node->next = node->prev = 0;
 778         node->data->is_last = true;
 779         if(0 != chain->tail)
 780                 chain->tail->data->is_last = false;
 781
 782         if(0 == chain->head)
 783                 chain->head = node;
 784         else {
 785                 FLAC__ASSERT(0 != chain->tail);
 786                 chain->tail->next = node;
 787                 node->prev = chain->tail;
 788         }
 789         chain->tail = node;
 790         chain->nodes++;
 791 }
 792
 793 static void chain_remove_node_(FLAC__Metadata_Chain *chain, FLAC__Metadata_Node *node)
 794 {
 795         FLAC__ASSERT(0 != chain);
 796         FLAC__ASSERT(0 != node);
 797
 798         if(node == chain->head)
 799                 chain->head = node->next;
 800         else
 801                 node->prev->next = node->next;
 802
 803         if(node == chain->tail)
 804                 chain->tail = node->prev;
 805         else
 806                 node->next->prev = node->prev;
 807
 808         if(0 != chain->tail)
 809                 chain->tail->data->is_last = true;
 810
 811         chain->nodes--;
 812 }
 813
 814 static void chain_delete_node_(FLAC__Metadata_Chain *chain, FLAC__Metadata_Node *node)
 815 {
 816         chain_remove_node_(chain, node);
 817         node_delete_(node);
 818 }
 819
 820 static unsigned chain_calculate_length_(FLAC__Metadata_Chain *chain)
 821 {
 822         const FLAC__Metadata_Node *node;
 823         unsigned length = 0;
 824         for(node = chain->head; node; node = node->next)
 825                 length += (FLAC__STREAM_METADATA_HEADER_LENGTH + node->data->length);
 826         return length;
 827 }
 828
 829 static void iterator_insert_node_(FLAC__Metadata_Iterator *iterator, FLAC__Metadata_Node *node)
 830 {
 831         FLAC__ASSERT(0 != node);
 832         FLAC__ASSERT(0 != node->data);
 833         FLAC__ASSERT(0 != iterator);
 834         FLAC__ASSERT(0 != iterator->current);
 835         FLAC__ASSERT(0 != iterator->chain);
 836         FLAC__ASSERT(0 != iterator->chain->head);
 837         FLAC__ASSERT(0 != iterator->chain->tail);
 838
 839         node->data->is_last = false;
 840
 841         node->prev = iterator->current->prev;
 842         node->next = iterator->current;
 843
 844         if(0 == node->prev)
 845                 iterator->chain->head = node;
 846         else
 847                 node->prev->next = node;
 848
 849         iterator->current->prev = node;
 850
 851         iterator->chain->nodes++;
 852 }
 853
 854 static void iterator_insert_node_after_(FLAC__Metadata_Iterator *iterator, FLAC__Metadata_Node *node)
 855 {
 856         FLAC__ASSERT(0 != node);
 857         FLAC__ASSERT(0 != node->data);
 858         FLAC__ASSERT(0 != iterator);
 859         FLAC__ASSERT(0 != iterator->current);
 860         FLAC__ASSERT(0 != iterator->chain);
 861         FLAC__ASSERT(0 != iterator->chain->head);
 862         FLAC__ASSERT(0 != iterator->chain->tail);
 863
 864         iterator->current->data->is_last = false;
 865
 866         node->prev = iterator->current;
 867         node->next = iterator->current->next;
 868
 869         if(0 == node->next)
 870                 iterator->chain->tail = node;
 871         else
 872                 node->next->prev = node;
 873
 874         node->prev->next = node;
 875
 876         iterator->chain->tail->data->is_last = true;
 877
 878         iterator->chain->nodes++;
 879 }
 880
 881 /* return true iff node and node->next are both padding */
 882 static FLAC__bool chain_merge_adjacent_padding_(FLAC__Metadata_Chain *chain, FLAC__Metadata_Node *node)
 883 {
 884         if(node->data->type == FLAC__METADATA_TYPE_PADDING && 0 != node->next && node->next->data->type == FLAC__METADATA_TYPE_PADDING) {
 885                 const unsigned growth = FLAC__STREAM_METADATA_HEADER_LENGTH + node->next->data->length;
 886                 node->data->length += growth;
 887
 888                 chain_delete_node_(chain, node->next);
 889                 return true;
 890         }
 891         else
 892                 return false;
 893 }
 894
 895 FLAC_API FLAC__Metadata_Chain *FLAC__metadata_chain_new()
 896 {
 897         FLAC__Metadata_Chain *chain = (FLAC__Metadata_Chain*)calloc(1, sizeof(FLAC__Metadata_Chain));
 898
 899         if(0 != chain) {
 900                 chain->filename = 0;
 901                 chain->head = chain->tail = 0;
 902                 chain->nodes = 0;
 903                 chain->status = FLAC__METADATA_CHAIN_STATUS_OK;
 904                 chain->initial_length = 0;
 905         }
 906
 907         return chain;
 908 }
 909
 910 FLAC_API void FLAC__metadata_chain_delete(FLAC__Metadata_Chain *chain)
 911 {
 912         FLAC__Metadata_Node *node, *next;
 913
 914         FLAC__ASSERT(0 != chain);
 915
 916         for(node = chain->head; node; ) {
 917                 next = node->next;
 918                 node_delete_(node);
 919                 node = next;
 920         }
 921
 922         if(0 != chain->filename)
 923                 free(chain->filename);
 924
 925         free(chain);
 926 }
 927
 928 FLAC_API FLAC__Metadata_ChainStatus FLAC__metadata_chain_status(FLAC__Metadata_Chain *chain)
 929 {
 930         FLAC__Metadata_ChainStatus status;
 931
 932         FLAC__ASSERT(0 != chain);
 933
 934         status = chain->status;
 935         chain->status = FLAC__METADATA_CHAIN_STATUS_OK;
 936         return status;
 937 }
 938
 939 FLAC_API FLAC__bool FLAC__metadata_chain_read(FLAC__Metadata_Chain *chain, const char *filename)
 940 {
 941         FLAC__Metadata_SimpleIterator *iterator;
 942         FLAC__Metadata_Node *node;
 943
 944         FLAC__ASSERT(0 != chain);
 945         FLAC__ASSERT(0 != filename);
 946
 947         if(0 == (chain->filename = strdup(filename))) {
 948                 chain->status = FLAC__METADATA_CHAIN_STATUS_MEMORY_ALLOCATION_ERROR;
 949                 return false;
 950         }
 951
 952         if(0 == (iterator = FLAC__metadata_simple_iterator_new())) {
 953                 chain->status = FLAC__METADATA_CHAIN_STATUS_MEMORY_ALLOCATION_ERROR;
 954                 return false;
 955         }
 956
 957         if(!FLAC__metadata_simple_iterator_init(iterator, filename, /*read_only=*/true, /*preserve_file_stats=*/false)) {
 958                 chain->status = get_equivalent_status_(iterator->status);
 959                 return false;
 960         }
 961
 962         chain->first_offset = iterator->offset[iterator->depth];
 963
 964         do {
 965                 node = node_new_();
 966                 if(0 == node) {
 967                         chain->status = FLAC__METADATA_CHAIN_STATUS_MEMORY_ALLOCATION_ERROR;
 968                         return false;
 969                 }
 970                 node->data = FLAC__metadata_simple_iterator_get_block(iterator);
 971                 if(0 == node->data) {
 972                         node_delete_(node);
 973                         chain->status = get_equivalent_status_(iterator->status);
 974                         return false;
 975                 }
 976                 chain_append_node_(chain, node);
 977         } while(FLAC__metadata_simple_iterator_next(iterator));
 978
 979         if(!iterator->is_last || iterator->status != FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK) {
 980                 chain->status = get_equivalent_status_(iterator->status);
 981                 return false;
 982         }
 983
 984         chain->last_offset = ftell(iterator->file) + iterator->length;
 985         FLAC__metadata_simple_iterator_delete(iterator);
 986
 987         chain->initial_length = chain_calculate_length_(chain);
 988         return true;
 989 }
 990
 991 FLAC_API FLAC__bool FLAC__metadata_chain_write(FLAC__Metadata_Chain *chain, FLAC__bool use_padding, FLAC__bool preserve_file_stats)
 992 {
 993         struct stat stats;
 994         const char *tempfile_path_prefix = 0;
 995         unsigned current_length;
 996
 997         FLAC__ASSERT(0 != chain);
 998
 999         current_length = chain_calculate_length_(chain);
1000
1001         if(use_padding) {
1002                 if(current_length < chain->initial_length && chain->tail->data->type == FLAC__METADATA_TYPE_PADDING) {
1003                         const unsigned delta = chain->initial_length - current_length;
1004                         chain->tail->data->length += delta;
1005                         current_length += delta;
1006                         FLAC__ASSERT(current_length == chain->initial_length);
1007                 }
1008                 else if(current_length + FLAC__STREAM_METADATA_HEADER_LENGTH <= chain->initial_length) {
1009                         FLAC__StreamMetadata *padding;
1010                         FLAC__Metadata_Node *node;
1011                         if(0 == (padding = FLAC__metadata_object_new(FLAC__METADATA_TYPE_PADDING))) {
1012                                 chain->status = FLAC__METADATA_CHAIN_STATUS_MEMORY_ALLOCATION_ERROR;
1013                                 return false;
1014                         }
1015                         padding->length = chain->initial_length - (FLAC__STREAM_METADATA_HEADER_LENGTH + current_length);
1016                         if(0 == (node = node_new_())) {
1017                                 FLAC__metadata_object_delete(padding);
1018                                 chain->status = FLAC__METADATA_CHAIN_STATUS_MEMORY_ALLOCATION_ERROR;
1019                                 return false;
1020                         }
1021                         node->data = padding;
1022                         chain_append_node_(chain, node);
1023                         current_length = chain_calculate_length_(chain);
1024                         FLAC__ASSERT(current_length == chain->initial_length);
1025                 }
1026                 else if(current_length > chain->initial_length) {
1027                         const unsigned delta = current_length - chain->initial_length;
1028                         if(chain->tail->data->type == FLAC__METADATA_TYPE_PADDING) {
1029                                 if(chain->tail->data->length + FLAC__STREAM_METADATA_HEADER_LENGTH == delta) {
1030                                         chain_delete_node_(chain, chain->tail);
1031                                         current_length = chain_calculate_length_(chain);
1032                                         FLAC__ASSERT(current_length == chain->initial_length);
1033                                 }
1034                                 else if(chain->tail->data->length >= delta) {
1035                                         chain->tail->data->length -= delta;
1036                                         current_length -= delta;
1037                                         FLAC__ASSERT(current_length == chain->initial_length);
1038                                 }
1039                         }
1040                 }
1041         }
1042
1043         if(preserve_file_stats)
1044                 get_file_stats_(chain->filename, &stats);
1045
1046         if(current_length == chain->initial_length) {
1047                 if(!chain_rewrite_chain_(chain))
1048                         return false;
1049         }
1050         else {
1051                 if(!chain_rewrite_file_(chain, tempfile_path_prefix))
1052                         return false;
1053         }
1054
1055         if(preserve_file_stats)
1056                 set_file_stats_(chain->filename, &stats);
1057
1058         /* recompute lengths and offsets if necessary */
1059         if(chain->initial_length != current_length) {
1060                 const FLAC__Metadata_Node *node;
1061                 chain->initial_length = current_length;
1062                 chain->last_offset = chain->first_offset;
1063                 for(node = chain->head; node; node = node->next)
1064                         chain->last_offset += (FLAC__STREAM_METADATA_HEADER_LENGTH + node->data->length);
1065         }
1066
1067         return true;
1068 }
1069
1070 FLAC_API void FLAC__metadata_chain_merge_padding(FLAC__Metadata_Chain *chain)
1071 {
1072         FLAC__Metadata_Node *node;
1073
1074         FLAC__ASSERT(0 != chain);
1075
1076         for(node = chain->head; node; ) {
1077                 if(!chain_merge_adjacent_padding_(chain, node))
1078                         node = node->next;
1079         }
1080 }
1081
1082 FLAC_API void FLAC__metadata_chain_sort_padding(FLAC__Metadata_Chain *chain)
1083 {
1084         FLAC__Metadata_Node *node, *save;
1085         unsigned i;
1086
1087         FLAC__ASSERT(0 != chain);
1088
1089         /*
1090          * Don't try and be too smart... this simple algo is good enough for
1091          * the small number of nodes that we deal with.
1092          */
1093         for(i = 0, node = chain->head; i < chain->nodes; i++) {
1094                 if(node->data->type == FLAC__METADATA_TYPE_PADDING) {
1095                         save = node->next;
1096                         chain_remove_node_(chain, node);
1097                         chain_append_node_(chain, node);
1098                         node = save;
1099                 }
1100                 else {
1101                         node = node->next;
1102                 }
1103         }
1104
1105         FLAC__metadata_chain_merge_padding(chain);
1106 }
1107
1108
1109 FLAC_API FLAC__Metadata_Iterator *FLAC__metadata_iterator_new()
1110 {
1111         FLAC__Metadata_Iterator *iterator = (FLAC__Metadata_Iterator*)calloc(1, sizeof(FLAC__Metadata_Iterator));
1112
1113         /* calloc() implies:
1114                 iterator->current = 0;
1115                 iterator->chain = 0;
1116         */
1117
1118         return iterator;
1119 }
1120
1121 FLAC_API void FLAC__metadata_iterator_delete(FLAC__Metadata_Iterator *iterator)
1122 {
1123         FLAC__ASSERT(0 != iterator);
1124
1125         free(iterator);
1126 }
1127
1128 FLAC_API void FLAC__metadata_iterator_init(FLAC__Metadata_Iterator *iterator, FLAC__Metadata_Chain *chain)
1129 {
1130         FLAC__ASSERT(0 != iterator);
1131         FLAC__ASSERT(0 != chain);
1132         FLAC__ASSERT(0 != chain->head);
1133
1134         iterator->chain = chain;
1135         iterator->current = chain->head;
1136 }
1137
1138 FLAC_API FLAC__bool FLAC__metadata_iterator_next(FLAC__Metadata_Iterator *iterator)
1139 {
1140         FLAC__ASSERT(0 != iterator);
1141
1142         if(0 == iterator->current || 0 == iterator->current->next)
1143                 return false;
1144
1145         iterator->current = iterator->current->next;
1146         return true;
1147 }
1148
1149 FLAC_API FLAC__bool FLAC__metadata_iterator_prev(FLAC__Metadata_Iterator *iterator)
1150 {
1151         FLAC__ASSERT(0 != iterator);
1152
1153         if(0 == iterator->current || 0 == iterator->current->prev)
1154                 return false;
1155
1156         iterator->current = iterator->current->prev;
1157         return true;
1158 }
1159
1160 FLAC_API FLAC__MetadataType FLAC__metadata_iterator_get_block_type(const FLAC__Metadata_Iterator *iterator)
1161 {
1162         FLAC__ASSERT(0 != iterator);
1163         FLAC__ASSERT(0 != iterator->current);
1164         FLAC__ASSERT(0 != iterator->current->data);
1165
1166         return iterator->current->data->type;
1167 }
1168
1169 FLAC_API FLAC__StreamMetadata *FLAC__metadata_iterator_get_block(FLAC__Metadata_Iterator *iterator)
1170 {
1171         FLAC__ASSERT(0 != iterator);
1172         FLAC__ASSERT(0 != iterator->current);
1173
1174         return iterator->current->data;
1175 }
1176
1177 FLAC_API FLAC__bool FLAC__metadata_iterator_set_block(FLAC__Metadata_Iterator *iterator, FLAC__StreamMetadata *block)
1178 {
1179         FLAC__ASSERT(0 != iterator);
1180         FLAC__ASSERT(0 != block);
1181         return FLAC__metadata_iterator_delete_block(iterator, false) && FLAC__metadata_iterator_insert_block_after(iterator, block);
1182 }
1183
1184 FLAC_API FLAC__bool FLAC__metadata_iterator_delete_block(FLAC__Metadata_Iterator *iterator, FLAC__bool replace_with_padding)
1185 {
1186         FLAC__Metadata_Node *save;
1187
1188         FLAC__ASSERT(0 != iterator);
1189         FLAC__ASSERT(0 != iterator->current);
1190
1191         if(0 == iterator->current->prev) {
1192                 FLAC__ASSERT(iterator->current->data->type == FLAC__METADATA_TYPE_STREAMINFO);
1193                 return false;
1194         }
1195
1196         save = iterator->current->prev;
1197
1198         if(replace_with_padding) {
1199                 FLAC__metadata_object_delete_data(iterator->current->data);
1200                 iterator->current->data->type = FLAC__METADATA_TYPE_PADDING;
1201         }
1202         else {
1203                 chain_delete_node_(iterator->chain, iterator->current);
1204         }
1205
1206         iterator->current = save;
1207         return true;
1208 }
1209
1210 FLAC_API FLAC__bool FLAC__metadata_iterator_insert_block_before(FLAC__Metadata_Iterator *iterator, FLAC__StreamMetadata *block)
1211 {
1212         FLAC__Metadata_Node *node;
1213
1214         FLAC__ASSERT(0 != iterator);
1215         FLAC__ASSERT(0 != iterator->current);
1216         FLAC__ASSERT(0 != block);
1217
1218         if(block->type == FLAC__METADATA_TYPE_STREAMINFO)
1219                 return false;
1220
1221         if(0 == iterator->current->prev) {
1222                 FLAC__ASSERT(iterator->current->data->type == FLAC__METADATA_TYPE_STREAMINFO);
1223                 return false;
1224         }
1225
1226         if(0 == (node = node_new_()))
1227                 return false;
1228
1229         node->data = block;
1230         iterator_insert_node_(iterator, node);
1231         iterator->current = node;
1232         return true;
1233 }
1234
1235 FLAC_API FLAC__bool FLAC__metadata_iterator_insert_block_after(FLAC__Metadata_Iterator *iterator, FLAC__StreamMetadata *block)
1236 {
1237         FLAC__Metadata_Node *node;
1238
1239         FLAC__ASSERT(0 != iterator);
1240         FLAC__ASSERT(0 != iterator->current);
1241         FLAC__ASSERT(0 != block);
1242
1243         if(block->type == FLAC__METADATA_TYPE_STREAMINFO)
1244                 return false;
1245
1246         if(0 == (node = node_new_()))
1247                 return false;
1248
1249         node->data = block;
1250         iterator_insert_node_after_(iterator, node);
1251         iterator->current = node;
1252         return true;
1253 }
1254
1255
1256 /****************************************************************************
1257  *
1258  * Local function definitions
1259  *
1260  ***************************************************************************/
1261
1262 void pack_uint32_(FLAC__uint32 val, FLAC__byte *b, unsigned bytes)
1263 {
1264         unsigned i;
1265
1266         b += bytes;
1267
1268         for(i = 0; i < bytes; i++) {
1269                 *(--b) = (FLAC__byte)(val & 0xff);
1270                 val >>= 8;
1271         }
1272 }
1273
1274 void pack_uint32_little_endian_(FLAC__uint32 val, FLAC__byte *b, unsigned bytes)
1275 {
1276         unsigned i;
1277
1278         for(i = 0; i < bytes; i++) {
1279                 *(b++) = (FLAC__byte)(val & 0xff);
1280                 val >>= 8;
1281         }
1282 }
1283
1284 void pack_uint64_(FLAC__uint64 val, FLAC__byte *b, unsigned bytes)
1285 {
1286         unsigned i;
1287
1288         b += bytes;
1289
1290         for(i = 0; i < bytes; i++) {
1291                 *(--b) = (FLAC__byte)(val & 0xff);
1292                 val >>= 8;
1293         }
1294 }
1295
1296 FLAC__uint32 unpack_uint32_(FLAC__byte *b, unsigned bytes)
1297 {
1298         FLAC__uint32 ret = 0;
1299         unsigned i;
1300
1301         for(i = 0; i < bytes; i++)
1302                 ret = (ret << 8) | (FLAC__uint32)(*b++);
1303
1304         return ret;
1305 }
1306
1307 FLAC__uint32 unpack_uint32_little_endian_(FLAC__byte *b, unsigned bytes)
1308 {
1309         FLAC__uint32 ret = 0;
1310         unsigned i;
1311
1312         b += bytes;
1313
1314         for(i = 0; i < bytes; i++)
1315                 ret = (ret << 8) | (FLAC__uint32)(*--b);
1316
1317         return ret;
1318 }
1319
1320 FLAC__uint64 unpack_uint64_(FLAC__byte *b, unsigned bytes)
1321 {
1322         FLAC__uint64 ret = 0;
1323         unsigned i;
1324
1325         for(i = 0; i < bytes; i++)
1326                 ret = (ret << 8) | (FLAC__uint64)(*b++);
1327
1328         return ret;
1329 }
1330
1331 FLAC__bool read_metadata_block_header_(FLAC__Metadata_SimpleIterator *iterator)
1332 {
1333         FLAC__byte raw_header[FLAC__STREAM_METADATA_HEADER_LENGTH];
1334
1335         FLAC__ASSERT(0 != iterator);
1336         FLAC__ASSERT(0 != iterator->file);
1337
1338         if(fread(raw_header, 1, FLAC__STREAM_METADATA_HEADER_LENGTH, iterator->file) != FLAC__STREAM_METADATA_HEADER_LENGTH) {
1339                 iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1340                 return false;
1341         }
1342
1343         iterator->is_last = raw_header[0] & 0x80? true : false;
1344         iterator->type = (FLAC__MetadataType)(raw_header[0] & 0x7f);
1345         iterator->length = unpack_uint32_(raw_header + 1, 3);
1346
1347         /* Note that we don't check:
1348          *    if(iterator->type >= FLAC__METADATA_TYPE_UNDEFINED)
1349          * we just will read in an opaque block
1350          */
1351
1352         return true;
1353 }
1354
1355 FLAC__bool read_metadata_block_data_(FLAC__Metadata_SimpleIterator *iterator, FLAC__StreamMetadata *block)
1356 {
1357         FLAC__ASSERT(0 != iterator);
1358         FLAC__ASSERT(0 != iterator->file);
1359
1360         switch(block->type) {
1361                 case FLAC__METADATA_TYPE_STREAMINFO:
1362                         iterator->status = read_metadata_block_data_streaminfo_(iterator->file, &block->data.stream_info);
1363                         break;
1364                 case FLAC__METADATA_TYPE_PADDING:
1365                         iterator->status = read_metadata_block_data_padding_(iterator->file, &block->data.padding, block->length);
1366                         break;
1367                 case FLAC__METADATA_TYPE_APPLICATION:
1368                         iterator->status = read_metadata_block_data_application_(iterator->file, &block->data.application, block->length);
1369                         break;
1370                 case FLAC__METADATA_TYPE_SEEKTABLE:
1371                         iterator->status = read_metadata_block_data_seektable_(iterator->file, &block->data.seek_table, block->length);
1372                         break;
1373                 case FLAC__METADATA_TYPE_VORBIS_COMMENT:
1374                         iterator->status = read_metadata_block_data_vorbis_comment_(iterator->file, &block->data.vorbis_comment);
1375                         break;
1376                 case FLAC__METADATA_TYPE_CUESHEET:
1377                         iterator->status = read_metadata_block_data_cuesheet_(iterator->file, &block->data.cue_sheet);
1378                         break;
1379                 default:
1380                         iterator->status = read_metadata_block_data_unknown_(iterator->file, &block->data.unknown, block->length);
1381                         break;
1382         }
1383
1384         return (iterator->status == FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK);
1385 }
1386
1387 FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_streaminfo_(FILE *file, FLAC__StreamMetadata_StreamInfo *block)
1388 {
1389         FLAC__byte buffer[FLAC__STREAM_METADATA_STREAMINFO_LENGTH], *b;
1390
1391         FLAC__ASSERT(0 != file);
1392
1393         if(fread(buffer, 1, FLAC__STREAM_METADATA_STREAMINFO_LENGTH, file) != FLAC__STREAM_METADATA_STREAMINFO_LENGTH)
1394                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1395
1396         b = buffer;
1397
1398         /* we are using hardcoded numbers for simplicity but we should
1399          * probably eventually write a bit-level unpacker and use the
1400          * _STREAMINFO_ constants.
1401          */
1402         block->min_blocksize = unpack_uint32_(b, 2); b += 2;
1403         block->max_blocksize = unpack_uint32_(b, 2); b += 2;
1404         block->min_framesize = unpack_uint32_(b, 3); b += 3;
1405         block->max_framesize = unpack_uint32_(b, 3); b += 3;
1406         block->sample_rate = (unpack_uint32_(b, 2) << 4) | ((unsigned)(b[2] & 0xf0) >> 4);
1407         block->channels = (unsigned)((b[2] & 0x0e) >> 1) + 1;
1408         block->bits_per_sample = ((((unsigned)(b[2] & 0x01)) << 4) | (((unsigned)(b[3] & 0xf0)) >> 4)) + 1;
1409         block->total_samples = (((FLAC__uint64)(b[3] & 0x0f)) << 32) | unpack_uint64_(b+4, 4);
1410         memcpy(block->md5sum, b+8, 16);
1411
1412         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK;
1413 }
1414
1415
1416 FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_padding_(FILE *file, FLAC__StreamMetadata_Padding *block, unsigned block_length)
1417 {
1418         FLAC__ASSERT(0 != file);
1419
1420         (void)block; /* nothing to do; we don't care about reading the padding bytes */
1421
1422         if(0 != fseek(file, block_length, SEEK_CUR))
1423                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_SEEK_ERROR;
1424
1425         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK;
1426 }
1427
1428 FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_application_(FILE *file, FLAC__StreamMetadata_Application *block, unsigned block_length)
1429 {
1430         const unsigned id_bytes = FLAC__STREAM_METADATA_APPLICATION_ID_LEN / 8;
1431
1432         FLAC__ASSERT(0 != file);
1433
1434         if(fread(block->id, 1, id_bytes, file) != id_bytes)
1435                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1436
1437         block_length -= id_bytes;
1438
1439         if(block_length == 0) {
1440                 block->data = 0;
1441         }
1442         else {
1443                 if(0 == (block->data = (FLAC__byte*)malloc(block_length)))
1444                         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_MEMORY_ALLOCATION_ERROR;
1445
1446                 if(fread(block->data, 1, block_length, file) != block_length)
1447                         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1448         }
1449
1450         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK;
1451 }
1452
1453 FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_seektable_(FILE *file, FLAC__StreamMetadata_SeekTable *block, unsigned block_length)
1454 {
1455         unsigned i;
1456         FLAC__byte buffer[FLAC__STREAM_METADATA_SEEKPOINT_LENGTH];
1457
1458         FLAC__ASSERT(0 != file);
1459         FLAC__ASSERT(block_length % FLAC__STREAM_METADATA_SEEKPOINT_LENGTH == 0);
1460
1461         block->num_points = block_length / FLAC__STREAM_METADATA_SEEKPOINT_LENGTH;
1462
1463         if(block->num_points == 0)
1464                 block->points = 0;
1465         else if(0 == (block->points = (FLAC__StreamMetadata_SeekPoint*)malloc(block->num_points * sizeof(FLAC__StreamMetadata_SeekPoint))))
1466                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_MEMORY_ALLOCATION_ERROR;
1467
1468         for(i = 0; i < block->num_points; i++) {
1469                 if(fread(buffer, 1, FLAC__STREAM_METADATA_SEEKPOINT_LENGTH, file) != FLAC__STREAM_METADATA_SEEKPOINT_LENGTH)
1470                         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1471                 /* some MAGIC NUMBERs here */
1472                 block->points[i].sample_number = unpack_uint64_(buffer, 8);
1473                 block->points[i].stream_offset = unpack_uint64_(buffer+8, 8);
1474                 block->points[i].frame_samples = unpack_uint32_(buffer+16, 2);
1475         }
1476
1477         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK;
1478 }
1479
1480 FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_vorbis_comment_entry_(FILE *file, FLAC__StreamMetadata_VorbisComment_Entry *entry)
1481 {
1482         const unsigned entry_length_len = FLAC__STREAM_METADATA_VORBIS_COMMENT_ENTRY_LENGTH_LEN / 8;
1483         FLAC__byte buffer[4]; /* magic number is asserted below */
1484
1485         FLAC__ASSERT(FLAC__STREAM_METADATA_VORBIS_COMMENT_ENTRY_LENGTH_LEN / 8 == 4);
1486         FLAC__ASSERT(0 != file);
1487
1488         if(fread(buffer, 1, entry_length_len, file) != entry_length_len)
1489                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1490         entry->length = unpack_uint32_little_endian_(buffer, entry_length_len);
1491
1492         if(0 != entry->entry)
1493                 free(entry->entry);
1494
1495         if(entry->length == 0) {
1496                 entry->entry = 0;
1497         }
1498         else {
1499                 if(0 == (entry->entry = (FLAC__byte*)malloc(entry->length)))
1500                         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_MEMORY_ALLOCATION_ERROR;
1501
1502                 if(fread(entry->entry, 1, entry->length, file) != entry->length)
1503                         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1504         }
1505
1506         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK;
1507 }
1508
1509 FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_vorbis_comment_(FILE *file, FLAC__StreamMetadata_VorbisComment *block)
1510 {
1511         unsigned i;
1512         FLAC__Metadata_SimpleIteratorStatus status;
1513         const unsigned num_comments_len = FLAC__STREAM_METADATA_VORBIS_COMMENT_NUM_COMMENTS_LEN / 8;
1514         FLAC__byte buffer[4]; /* magic number is asserted below */
1515
1516         FLAC__ASSERT(FLAC__STREAM_METADATA_VORBIS_COMMENT_NUM_COMMENTS_LEN / 8 == 4);
1517         FLAC__ASSERT(0 != file);
1518
1519         if(FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK != (status = read_metadata_block_data_vorbis_comment_entry_(file, &(block->vendor_string))))
1520                 return status;
1521
1522         if(fread(buffer, 1, num_comments_len, file) != num_comments_len)
1523                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1524         block->num_comments = unpack_uint32_little_endian_(buffer, num_comments_len);
1525
1526         if(block->num_comments == 0) {
1527                 block->comments = 0;
1528         }
1529         else if(0 == (block->comments = (FLAC__StreamMetadata_VorbisComment_Entry*)calloc(block->num_comments, sizeof(FLAC__StreamMetadata_VorbisComment_Entry))))
1530                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_MEMORY_ALLOCATION_ERROR;
1531
1532         for(i = 0; i < block->num_comments; i++) {
1533                 if(FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK != (status = read_metadata_block_data_vorbis_comment_entry_(file, block->comments + i)))
1534                         return status;
1535         }
1536
1537         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK;
1538 }
1539
1540 FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_cuesheet_track_(FILE *file, FLAC__StreamMetadata_CueSheet_Track *track)
1541 {
1542         unsigned i, len;
1543         FLAC__byte buffer[32]; /* asserted below that this is big enough */
1544
1545         FLAC__ASSERT(sizeof(buffer) >= sizeof(FLAC__uint64));
1546         FLAC__ASSERT(sizeof(buffer) >= FLAC__STREAM_METADATA_CUESHEET_INDEX_RESERVED_LEN/8);
1547         FLAC__ASSERT(sizeof(buffer) >= (FLAC__STREAM_METADATA_CUESHEET_TRACK_TYPE_LEN + FLAC__STREAM_METADATA_CUESHEET_TRACK_PRE_EMPHASIS_LEN + FLAC__STREAM_METADATA_CUESHEET_TRACK_RESERVED_LEN) / 8);
1548
1549         FLAC__ASSERT(0 != file);
1550
1551         FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_TRACK_OFFSET_LEN % 8 == 0);
1552         len = FLAC__STREAM_METADATA_CUESHEET_TRACK_OFFSET_LEN / 8;
1553         if(fread(buffer, 1, len, file) != len)
1554                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1555         track->offset = unpack_uint64_(buffer, len);
1556
1557         FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_TRACK_NUMBER_LEN % 8 == 0);
1558         len = FLAC__STREAM_METADATA_CUESHEET_TRACK_NUMBER_LEN / 8;
1559         if(fread(buffer, 1, len, file) != len)
1560                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1561         track->number = (FLAC__byte)unpack_uint32_(buffer, len);
1562
1563         FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_TRACK_ISRC_LEN % 8 == 0);
1564         len = FLAC__STREAM_METADATA_CUESHEET_TRACK_ISRC_LEN / 8;
1565         if(fread(track->isrc, 1, len, file) != len)
1566                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1567
1568         FLAC__ASSERT((FLAC__STREAM_METADATA_CUESHEET_TRACK_TYPE_LEN + FLAC__STREAM_METADATA_CUESHEET_TRACK_PRE_EMPHASIS_LEN + FLAC__STREAM_METADATA_CUESHEET_TRACK_RESERVED_LEN) % 8 == 0);
1569         len = (FLAC__STREAM_METADATA_CUESHEET_TRACK_TYPE_LEN + FLAC__STREAM_METADATA_CUESHEET_TRACK_PRE_EMPHASIS_LEN + FLAC__STREAM_METADATA_CUESHEET_TRACK_RESERVED_LEN) / 8;
1570         if(fread(buffer, 1, len, file) != len)
1571                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1572         FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_TRACK_TYPE_LEN == 1);
1573         FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_TRACK_PRE_EMPHASIS_LEN == 1);
1574         track->type = buffer[0] >> 7;
1575         track->pre_emphasis = (buffer[0] >> 6) & 1;
1576
1577         FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_TRACK_NUM_INDICES_LEN % 8 == 0);
1578         len = FLAC__STREAM_METADATA_CUESHEET_TRACK_NUM_INDICES_LEN / 8;
1579         if(fread(buffer, 1, len, file) != len)
1580                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1581         track->num_indices = (FLAC__byte)unpack_uint32_(buffer, len);
1582
1583         if(track->num_indices == 0) {
1584                 track->indices = 0;
1585         }
1586         else if(0 == (track->indices = (FLAC__StreamMetadata_CueSheet_Index*)calloc(track->num_indices, sizeof(FLAC__StreamMetadata_CueSheet_Index))))
1587                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_MEMORY_ALLOCATION_ERROR;
1588
1589         for(i = 0; i < track->num_indices; i++) {
1590                 FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_INDEX_OFFSET_LEN % 8 == 0);
1591                 len = FLAC__STREAM_METADATA_CUESHEET_INDEX_OFFSET_LEN / 8;
1592                 if(fread(buffer, 1, len, file) != len)
1593                         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1594                 track->indices[i].offset = unpack_uint64_(buffer, len);
1595
1596                 FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_INDEX_NUMBER_LEN % 8 == 0);
1597                 len = FLAC__STREAM_METADATA_CUESHEET_INDEX_NUMBER_LEN / 8;
1598                 if(fread(buffer, 1, len, file) != len)
1599                         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1600                 track->indices[i].number = (FLAC__byte)unpack_uint32_(buffer, len);
1601
1602                 FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_INDEX_RESERVED_LEN % 8 == 0);
1603                 len = FLAC__STREAM_METADATA_CUESHEET_INDEX_RESERVED_LEN / 8;
1604                 if(fread(buffer, 1, len, file) != len)
1605                         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1606         }
1607
1608         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK;
1609 }
1610
1611 FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_cuesheet_(FILE *file, FLAC__StreamMetadata_CueSheet *block)
1612 {
1613         unsigned i, len;
1614         FLAC__Metadata_SimpleIteratorStatus status;
1615         FLAC__byte buffer[1024]; /* MSVC needs a constant expression so we put a magic number and assert */
1616
1617         FLAC__ASSERT(0 != file);
1618         FLAC__ASSERT((FLAC__STREAM_METADATA_CUESHEET_IS_CD_LEN + FLAC__STREAM_METADATA_CUESHEET_RESERVED_LEN)/8 <= sizeof(buffer));
1619         FLAC__ASSERT(sizeof(FLAC__uint64) <= sizeof(buffer));
1620
1621         FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_MEDIA_CATALOG_NUMBER_LEN % 8 == 0);
1622         len = FLAC__STREAM_METADATA_CUESHEET_MEDIA_CATALOG_NUMBER_LEN / 8;
1623         if(fread(block->media_catalog_number, 1, len, file) != len)
1624                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1625
1626         FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_LEAD_IN_LEN % 8 == 0);
1627         len = FLAC__STREAM_METADATA_CUESHEET_LEAD_IN_LEN / 8;
1628         if(fread(buffer, 1, len, file) != len)
1629                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1630         block->lead_in = unpack_uint64_(buffer, len);
1631
1632         FLAC__ASSERT((FLAC__STREAM_METADATA_CUESHEET_IS_CD_LEN + FLAC__STREAM_METADATA_CUESHEET_RESERVED_LEN) % 8 == 0);
1633         len = (FLAC__STREAM_METADATA_CUESHEET_IS_CD_LEN + FLAC__STREAM_METADATA_CUESHEET_RESERVED_LEN) / 8;
1634         if(fread(buffer, 1, len, file) != len)
1635                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1636         block->is_cd = buffer[0]&0x80? true : false;
1637
1638         FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_NUM_TRACKS_LEN % 8 == 0);
1639         len = FLAC__STREAM_METADATA_CUESHEET_NUM_TRACKS_LEN / 8;
1640         if(fread(buffer, 1, len, file) != len)
1641                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1642         block->num_tracks = unpack_uint32_(buffer, len);
1643
1644         if(block->num_tracks == 0) {
1645                 block->tracks = 0;
1646         }
1647         else if(0 == (block->tracks = (FLAC__StreamMetadata_CueSheet_Track*)calloc(block->num_tracks, sizeof(FLAC__StreamMetadata_CueSheet_Track))))
1648                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_MEMORY_ALLOCATION_ERROR;
1649
1650         for(i = 0; i < block->num_tracks; i++) {
1651                 if(FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK != (status = read_metadata_block_data_cuesheet_track_(file, block->tracks + i)))
1652                         return status;
1653         }
1654
1655         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK;
1656 }
1657
1658 FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_unknown_(FILE *file, FLAC__StreamMetadata_Unknown *block, unsigned block_length)
1659 {
1660         FLAC__ASSERT(0 != file);
1661
1662         if(block_length == 0) {
1663                 block->data = 0;
1664         }
1665         else {
1666                 if(0 == (block->data = (FLAC__byte*)malloc(block_length)))
1667                         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_MEMORY_ALLOCATION_ERROR;
1668
1669                 if(fread(block->data, 1, block_length, file) != block_length)
1670                         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1671         }
1672
1673         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK;
1674 }
1675
1676 FLAC__bool write_metadata_block_header_(FILE *file, FLAC__Metadata_SimpleIteratorStatus *status, const FLAC__StreamMetadata *block)
1677 {
1678         FLAC__byte buffer[FLAC__STREAM_METADATA_HEADER_LENGTH];
1679
1680         FLAC__ASSERT(0 != file);
1681         FLAC__ASSERT(0 != status);
1682         FLAC__ASSERT(block->length < (1u << FLAC__STREAM_METADATA_LENGTH_LEN));
1683
1684         buffer[0] = (block->is_last? 0x80 : 0) | (FLAC__byte)block->type;
1685         pack_uint32_(block->length, buffer + 1, 3);
1686
1687         if(local__fwrite(buffer, 1, FLAC__STREAM_METADATA_HEADER_LENGTH, file) != FLAC__STREAM_METADATA_HEADER_LENGTH) {
1688                 *status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1689                 return false;
1690         }
1691
1692         return true;
1693 }
1694
1695 FLAC__bool write_metadata_block_data_(FILE *file, FLAC__Metadata_SimpleIteratorStatus *status, const FLAC__StreamMetadata *block)
1696 {
1697         FLAC__ASSERT(0 != file);
1698         FLAC__ASSERT(0 != status);
1699
1700         switch(block->type) {
1701                 case FLAC__METADATA_TYPE_STREAMINFO:
1702                         *status = write_metadata_block_data_streaminfo_(file, &block->data.stream_info);
1703                         break;
1704                 case FLAC__METADATA_TYPE_PADDING:
1705                         *status = write_metadata_block_data_padding_(file, &block->data.padding, block->length);
1706                         break;
1707                 case FLAC__METADATA_TYPE_APPLICATION:
1708                         *status = write_metadata_block_data_application_(file, &block->data.application, block->length);
1709                         break;
1710                 case FLAC__METADATA_TYPE_SEEKTABLE:
1711                         *status = write_metadata_block_data_seektable_(file, &block->data.seek_table);
1712                         break;
1713                 case FLAC__METADATA_TYPE_VORBIS_COMMENT:
1714                         *status = write_metadata_block_data_vorbis_comment_(file, &block->data.vorbis_comment);
1715                         break;
1716                 case FLAC__METADATA_TYPE_CUESHEET:
1717                         *status = write_metadata_block_data_cuesheet_(file, &block->data.cue_sheet);
1718                         break;
1719                 default:
1720                         *status = write_metadata_block_data_unknown_(file, &block->data.unknown, block->length);
1721                         break;
1722         }
1723         return (*status == FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK);
1724 }
1725
1726 FLAC__Metadata_SimpleIteratorStatus write_metadata_block_data_streaminfo_(FILE *file, const FLAC__StreamMetadata_StreamInfo *block)
1727 {
1728         FLAC__byte buffer[FLAC__STREAM_METADATA_STREAMINFO_LENGTH];
1729         const unsigned channels1 = block->channels - 1;
1730         const unsigned bps1 = block->bits_per_sample - 1;
1731
1732         FLAC__ASSERT(0 != file);
1733
1734         /* we are using hardcoded numbers for simplicity but we should
1735          * probably eventually write a bit-level packer and use the
1736          * _STREAMINFO_ constants.
1737          */
1738         pack_uint32_(block->min_blocksize, buffer, 2);
1739         pack_uint32_(block->max_blocksize, buffer+2, 2);
1740         pack_uint32_(block->min_framesize, buffer+4, 3);
1741         pack_uint32_(block->max_framesize, buffer+7, 3);
1742         buffer[10] = (block->sample_rate >> 12) & 0xff;
1743         buffer[11] = (block->sample_rate >> 4) & 0xff;
1744         buffer[12] = ((block->sample_rate & 0x0f) << 4) | (channels1 << 1) | (bps1 >> 4);
1745         buffer[13] = (FLAC__byte)(((bps1 & 0x0f) << 4) | ((block->total_samples >> 32) & 0x0f));
1746         pack_uint32_((FLAC__uint32)block->total_samples, buffer+14, 4);
1747         memcpy(buffer+18, block->md5sum, 16);
1748
1749         if(local__fwrite(buffer, 1, FLAC__STREAM_METADATA_STREAMINFO_LENGTH, file) != FLAC__STREAM_METADATA_STREAMINFO_LENGTH)
1750                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1751
1752         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK;
1753 }
1754
1755 FLAC__Metadata_SimpleIteratorStatus write_metadata_block_data_padding_(FILE *file, const FLAC__StreamMetadata_Padding *block, unsigned block_length)
1756 {
1757         unsigned i, n = block_length;
1758         FLAC__byte buffer[1024];
1759
1760         FLAC__ASSERT(0 != file);
1761
1762         (void)block;
1763
1764         memset(buffer, 0, 1024);
1765
1766         for(i = 0; i < n/1024; i++)
1767                 if(local__fwrite(buffer, 1, 1024, file) != 1024)
1768                         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1769
1770         n %= 1024;
1771
1772         if(local__fwrite(buffer, 1, n, file) != n)
1773                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1774
1775         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK;
1776 }
1777
1778 FLAC__Metadata_SimpleIteratorStatus write_metadata_block_data_application_(FILE *file, const FLAC__StreamMetadata_Application *block, unsigned block_length)
1779 {
1780         const unsigned id_bytes = FLAC__STREAM_METADATA_APPLICATION_ID_LEN / 8;
1781
1782         FLAC__ASSERT(0 != file);
1783
1784         if(local__fwrite(block->id, 1, id_bytes, file) != id_bytes)
1785                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1786
1787         block_length -= id_bytes;
1788
1789         if(local__fwrite(block->data, 1, block_length, file) != block_length)
1790                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1791
1792         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK;
1793 }
1794
1795 FLAC__Metadata_SimpleIteratorStatus write_metadata_block_data_seektable_(FILE *file, const FLAC__StreamMetadata_SeekTable *block)
1796 {
1797         unsigned i;
1798         FLAC__byte buffer[FLAC__STREAM_METADATA_SEEKPOINT_LENGTH];
1799
1800         FLAC__ASSERT(0 != file);
1801
1802         for(i = 0; i < block->num_points; i++) {
1803                 /* some MAGIC NUMBERs here */
1804                 pack_uint64_(block->points[i].sample_number, buffer, 8);
1805                 pack_uint64_(block->points[i].stream_offset, buffer+8, 8);
1806                 pack_uint32_(block->points[i].frame_samples, buffer+16, 2);
1807                 if(local__fwrite(buffer, 1, FLAC__STREAM_METADATA_SEEKPOINT_LENGTH, file) != FLAC__STREAM_METADATA_SEEKPOINT_LENGTH)
1808                         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1809         }
1810
1811         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK;
1812 }
1813
1814 FLAC__Metadata_SimpleIteratorStatus write_metadata_block_data_vorbis_comment_(FILE *file, const FLAC__StreamMetadata_VorbisComment *block)
1815 {
1816         unsigned i;
1817         const unsigned entry_length_len = FLAC__STREAM_METADATA_VORBIS_COMMENT_ENTRY_LENGTH_LEN / 8;
1818         const unsigned num_comments_len = FLAC__STREAM_METADATA_VORBIS_COMMENT_NUM_COMMENTS_LEN / 8;
1819         FLAC__byte buffer[4]; /* magic number is asserted below */
1820
1821         FLAC__ASSERT(max(FLAC__STREAM_METADATA_VORBIS_COMMENT_ENTRY_LENGTH_LEN, FLAC__STREAM_METADATA_VORBIS_COMMENT_NUM_COMMENTS_LEN) / 8 == 4);
1822         FLAC__ASSERT(0 != file);
1823
1824         pack_uint32_little_endian_(block->vendor_string.length, buffer, entry_length_len);
1825         if(local__fwrite(buffer, 1, entry_length_len, file) != entry_length_len)
1826                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1827         if(local__fwrite(block->vendor_string.entry, 1, block->vendor_string.length, file) != block->vendor_string.length)
1828                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1829
1830         pack_uint32_little_endian_(block->num_comments, buffer, num_comments_len);
1831         if(local__fwrite(buffer, 1, num_comments_len, file) != num_comments_len)
1832                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1833
1834         for(i = 0; i < block->num_comments; i++) {
1835                 pack_uint32_little_endian_(block->comments[i].length, buffer, entry_length_len);
1836                 if(local__fwrite(buffer, 1, entry_length_len, file) != entry_length_len)
1837                         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1838                 if(local__fwrite(block->comments[i].entry, 1, block->comments[i].length, file) != block->comments[i].length)
1839                         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1840         }
1841
1842         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK;
1843 }
1844
1845 FLAC__Metadata_SimpleIteratorStatus write_metadata_block_data_cuesheet_(FILE *file, const FLAC__StreamMetadata_CueSheet *block)
1846 {
1847         unsigned i, j, len;
1848         FLAC__byte buffer[1024]; /* asserted below that this is big enough */
1849
1850         FLAC__ASSERT(sizeof(buffer) >= sizeof(FLAC__uint64));
1851         FLAC__ASSERT(sizeof(buffer) >= FLAC__STREAM_METADATA_CUESHEET_RESERVED_LEN/8);
1852         FLAC__ASSERT(sizeof(buffer) >= (FLAC__STREAM_METADATA_CUESHEET_TRACK_TYPE_LEN + FLAC__STREAM_METADATA_CUESHEET_TRACK_PRE_EMPHASIS_LEN + FLAC__STREAM_METADATA_CUESHEET_IS_CD_LEN + FLAC__STREAM_METADATA_CUESHEET_TRACK_RESERVED_LEN)/8);
1853         FLAC__ASSERT(sizeof(buffer) >= FLAC__STREAM_METADATA_CUESHEET_INDEX_RESERVED_LEN/8);
1854
1855         FLAC__ASSERT(0 != file);
1856
1857         FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_MEDIA_CATALOG_NUMBER_LEN % 8 == 0);
1858         len = FLAC__STREAM_METADATA_CUESHEET_MEDIA_CATALOG_NUMBER_LEN / 8;
1859         if(local__fwrite(block->media_catalog_number, 1, len, file) != len)
1860                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1861
1862         FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_LEAD_IN_LEN % 8 == 0);
1863         len = FLAC__STREAM_METADATA_CUESHEET_LEAD_IN_LEN / 8;
1864         pack_uint64_(block->lead_in, buffer, len);
1865         if(local__fwrite(buffer, 1, len, file) != len)
1866                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1867
1868         FLAC__ASSERT((FLAC__STREAM_METADATA_CUESHEET_IS_CD_LEN + FLAC__STREAM_METADATA_CUESHEET_RESERVED_LEN) % 8 == 0);
1869         len = (FLAC__STREAM_METADATA_CUESHEET_IS_CD_LEN + FLAC__STREAM_METADATA_CUESHEET_RESERVED_LEN) / 8;
1870         memset(buffer, 0, len);
1871         if(block->is_cd)
1872                 buffer[0] |= 0x80;
1873         if(local__fwrite(buffer, 1, len, file) != len)
1874                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1875
1876         FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_NUM_TRACKS_LEN % 8 == 0);
1877         len = FLAC__STREAM_METADATA_CUESHEET_NUM_TRACKS_LEN / 8;
1878         pack_uint32_(block->num_tracks, buffer, len);
1879         if(local__fwrite(buffer, 1, len, file) != len)
1880                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1881
1882         for(i = 0; i < block->num_tracks; i++) {
1883                 FLAC__StreamMetadata_CueSheet_Track *track = block->tracks + i;
1884
1885                 FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_TRACK_OFFSET_LEN % 8 == 0);
1886                 len = FLAC__STREAM_METADATA_CUESHEET_TRACK_OFFSET_LEN / 8;
1887                 pack_uint64_(track->offset, buffer, len);
1888                 if(local__fwrite(buffer, 1, len, file) != len)
1889                         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1890
1891                 FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_TRACK_NUMBER_LEN % 8 == 0);
1892                 len = FLAC__STREAM_METADATA_CUESHEET_TRACK_NUMBER_LEN / 8;
1893                 pack_uint32_(track->number, buffer, len);
1894                 if(local__fwrite(buffer, 1, len, file) != len)
1895                         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1896
1897                 FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_TRACK_ISRC_LEN % 8 == 0);
1898                 len = FLAC__STREAM_METADATA_CUESHEET_TRACK_ISRC_LEN / 8;
1899                 if(local__fwrite(track->isrc, 1, len, file) != len)
1900                         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1901
1902                 FLAC__ASSERT((FLAC__STREAM_METADATA_CUESHEET_TRACK_TYPE_LEN + FLAC__STREAM_METADATA_CUESHEET_TRACK_PRE_EMPHASIS_LEN + FLAC__STREAM_METADATA_CUESHEET_TRACK_RESERVED_LEN) % 8 == 0);
1903                 len = (FLAC__STREAM_METADATA_CUESHEET_TRACK_TYPE_LEN + FLAC__STREAM_METADATA_CUESHEET_TRACK_PRE_EMPHASIS_LEN + FLAC__STREAM_METADATA_CUESHEET_TRACK_RESERVED_LEN) / 8;
1904                 memset(buffer, 0, len);
1905                 buffer[0] = (track->type << 7) | (track->pre_emphasis << 6);
1906                 if(local__fwrite(buffer, 1, len, file) != len)
1907                         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1908
1909                 FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_TRACK_NUM_INDICES_LEN % 8 == 0);
1910                 len = FLAC__STREAM_METADATA_CUESHEET_TRACK_NUM_INDICES_LEN / 8;
1911                 pack_uint32_(track->num_indices, buffer, len);
1912                 if(local__fwrite(buffer, 1, len, file) != len)
1913                         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1914
1915                 for(j = 0; j < track->num_indices; j++) {
1916                         FLAC__StreamMetadata_CueSheet_Index *index = track->indices + j;
1917
1918                         FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_INDEX_OFFSET_LEN % 8 == 0);
1919                         len = FLAC__STREAM_METADATA_CUESHEET_INDEX_OFFSET_LEN / 8;
1920                         pack_uint64_(index->offset, buffer, len);
1921                         if(local__fwrite(buffer, 1, len, file) != len)
1922                                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1923
1924                         FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_INDEX_NUMBER_LEN % 8 == 0);
1925                         len = FLAC__STREAM_METADATA_CUESHEET_INDEX_NUMBER_LEN / 8;
1926                         pack_uint32_(index->number, buffer, len);
1927                         if(local__fwrite(buffer, 1, len, file) != len)
1928                                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1929
1930                         FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_INDEX_RESERVED_LEN % 8 == 0);
1931                         len = FLAC__STREAM_METADATA_CUESHEET_INDEX_RESERVED_LEN / 8;
1932                         memset(buffer, 0, len);
1933                         if(local__fwrite(buffer, 1, len, file) != len)
1934                                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1935                 }
1936         }
1937
1938         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK;
1939 }
1940
1941 FLAC__Metadata_SimpleIteratorStatus write_metadata_block_data_unknown_(FILE *file, const FLAC__StreamMetadata_Unknown *block, unsigned block_length)
1942 {
1943         FLAC__ASSERT(0 != file);
1944
1945         if(local__fwrite(block->data, 1, block_length, file) != block_length)
1946                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1947
1948         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK;
1949 }
1950
1951 FLAC__bool write_metadata_block_stationary_(FLAC__Metadata_SimpleIterator *iterator, const FLAC__StreamMetadata *block)
1952 {
1953         if(0 != fseek(iterator->file, iterator->offset[iterator->depth], SEEK_SET)) {
1954                 iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_SEEK_ERROR;
1955                 return false;
1956         }
1957
1958         if(!write_metadata_block_header_(iterator->file, &iterator->status, block))
1959                 return false;
1960
1961         if(!write_metadata_block_data_(iterator->file, &iterator->status, block))
1962                 return false;
1963
1964         if(0 != fseek(iterator->file, iterator->offset[iterator->depth], SEEK_SET)) {
1965                 iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_SEEK_ERROR;
1966                 return false;
1967         }
1968
1969         return read_metadata_block_header_(iterator);
1970 }
1971
1972 FLAC__bool write_metadata_block_stationary_with_padding_(FLAC__Metadata_SimpleIterator *iterator, FLAC__StreamMetadata *block, unsigned padding_length, FLAC__bool padding_is_last)
1973 {
1974         FLAC__StreamMetadata *padding;
1975
1976         if(0 != fseek(iterator->file, iterator->offset[iterator->depth], SEEK_SET)) {
1977                 iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_SEEK_ERROR;
1978                 return false;
1979         }
1980
1981         block->is_last = false;
1982
1983         if(!write_metadata_block_header_(iterator->file, &iterator->status, block))
1984                 return false;
1985
1986         if(!write_metadata_block_data_(iterator->file, &iterator->status, block))
1987                 return false;
1988
1989         if(0 == (padding = FLAC__metadata_object_new(FLAC__METADATA_TYPE_PADDING)))
1990                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_MEMORY_ALLOCATION_ERROR;
1991
1992         padding->is_last = padding_is_last;
1993         padding->length = padding_length;
1994
1995         if(!write_metadata_block_header_(iterator->file, &iterator->status, padding)) {
1996                 FLAC__metadata_object_delete(padding);
1997                 return false;
1998         }
1999
2000         if(!write_metadata_block_data_(iterator->file, &iterator->status, padding)) {
2001                 FLAC__metadata_object_delete(padding);
2002                 return false;
2003         }
2004
2005         FLAC__metadata_object_delete(padding);
2006
2007         if(0 != fseek(iterator->file, iterator->offset[iterator->depth], SEEK_SET)) {
2008                 iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_SEEK_ERROR;
2009                 return false;
2010         }
2011
2012         return read_metadata_block_header_(iterator);
2013 }
2014
2015 FLAC__bool rewrite_whole_file_(FLAC__Metadata_SimpleIterator *iterator, FLAC__StreamMetadata *block, FLAC__bool append)
2016 {
2017         FILE *tempfile;
2018         char *tempfilename;
2019         int fixup_is_last_code = 0; /* 0 => no need to change any is_last flags */
2020         long fixup_is_last_flag_offset = -1;
2021
2022         FLAC__ASSERT(0 != block || append == false);
2023
2024         if(iterator->is_last) {
2025                 if(append) {
2026                         fixup_is_last_code = 1; /* 1 => clear the is_last flag at the following offset */
2027                         fixup_is_last_flag_offset = iterator->offset[iterator->depth];
2028                 }
2029                 else if(0 == block) {
2030                         simple_iterator_push_(iterator);
2031                         if(!FLAC__metadata_simple_iterator_prev(iterator)) {
2032                                 (void)simple_iterator_pop_(iterator);
2033                                 return false;
2034                         }
2035                         fixup_is_last_code = -1; /* -1 => set the is_last the flag at the following offset */
2036                         fixup_is_last_flag_offset = iterator->offset[iterator->depth];
2037                         if(!simple_iterator_pop_(iterator))
2038                                 return false;
2039                 }
2040         }
2041
2042         if(!simple_iterator_copy_file_prefix_(iterator, &tempfile, &tempfilename, append))
2043                 return false;
2044
2045         if(0 != block) {
2046                 if(!write_metadata_block_header_(tempfile, &iterator->status, block)) {
2047                         cleanup_tempfile_(&tempfile, &tempfilename);
2048                         return false;
2049                 }
2050
2051                 if(!write_metadata_block_data_(tempfile, &iterator->status, block)) {
2052                         cleanup_tempfile_(&tempfile, &tempfilename);
2053                         return false;
2054                 }
2055         }
2056
2057         if(!simple_iterator_copy_file_postfix_(iterator, &tempfile, &tempfilename, fixup_is_last_code, fixup_is_last_flag_offset, block==0))
2058                 return false;
2059
2060         if(append)
2061                 return FLAC__metadata_simple_iterator_next(iterator);
2062
2063         return true;
2064 }
2065
2066 FLAC__bool chain_rewrite_chain_(FLAC__Metadata_Chain *chain)
2067 {
2068         FILE *f;
2069         FLAC__Metadata_Node *node;
2070         FLAC__Metadata_SimpleIteratorStatus status;
2071
2072         FLAC__ASSERT(0 != chain);
2073         FLAC__ASSERT(0 != chain->filename);
2074         FLAC__ASSERT(0 != chain->head);
2075
2076         if(0 == (f = fopen(chain->filename, "r+b"))) {
2077                 chain->status = FLAC__METADATA_CHAIN_STATUS_ERROR_OPENING_FILE;
2078                 return false;
2079         }
2080         if(0 != fseek(f, chain->first_offset, SEEK_SET)) {
2081                 chain->status = FLAC__METADATA_CHAIN_STATUS_SEEK_ERROR;
2082                 return false;
2083         }
2084
2085         for(node = chain->head; node; node = node->next) {
2086                 if(!write_metadata_block_header_(f, &status, node->data)) {
2087                         chain->status = get_equivalent_status_(status);
2088                         return false;
2089                 }
2090                 if(!write_metadata_block_data_(f, &status, node->data)) {
2091                         chain->status = get_equivalent_status_(status);
2092                         return false;
2093                 }
2094         }
2095
2096         /*FLAC__ASSERT(fflush(), ftell() == chain->last_offset);*/
2097
2098         (void)fclose(f);
2099
2100         return true;
2101 }
2102
2103 FLAC__bool chain_rewrite_file_(FLAC__Metadata_Chain *chain, const char *tempfile_path_prefix)
2104 {
2105         FILE *f, *tempfile;
2106         char *tempfilename;
2107         FLAC__Metadata_SimpleIteratorStatus status;
2108         const FLAC__Metadata_Node *node;
2109
2110         FLAC__ASSERT(0 != chain);
2111         FLAC__ASSERT(0 != chain->filename);
2112         FLAC__ASSERT(0 != chain->head);
2113
2114         /* copy the file prefix (data up to first metadata block */
2115         if(0 == (f = fopen(chain->filename, "rb"))) {
2116                 chain->status = FLAC__METADATA_CHAIN_STATUS_ERROR_OPENING_FILE;
2117                 return false;
2118         }
2119         if(!open_tempfile_(chain->filename, tempfile_path_prefix, &tempfile, &tempfilename, &status)) {
2120                 chain->status = get_equivalent_status_(status);
2121                 cleanup_tempfile_(&tempfile, &tempfilename);
2122                 return false;
2123         }
2124         if(!copy_n_bytes_from_file_(f, tempfile, chain->first_offset, &status)) {
2125                 chain->status = get_equivalent_status_(status);
2126                 cleanup_tempfile_(&tempfile, &tempfilename);
2127                 return false;
2128         }
2129
2130         /* write the metadata */
2131         for(node = chain->head; node; node = node->next) {
2132                 if(!write_metadata_block_header_(tempfile, &status, node->data)) {
2133                         chain->status = get_equivalent_status_(status);
2134                         return false;
2135                 }
2136                 if(!write_metadata_block_data_(tempfile, &status, node->data)) {
2137                         chain->status = get_equivalent_status_(status);
2138                         return false;
2139                 }
2140         }
2141         /*FLAC__ASSERT(fflush(), ftell() == chain->last_offset);*/
2142
2143         /* copy the file postfix (everything after the metadata) */
2144         if(0 != fseek(f, chain->last_offset, SEEK_SET)) {
2145                 cleanup_tempfile_(&tempfile, &tempfilename);
2146                 chain->status = FLAC__METADATA_CHAIN_STATUS_SEEK_ERROR;
2147                 return false;
2148         }
2149         if(!copy_remaining_bytes_from_file_(f, tempfile, &status)) {
2150                 cleanup_tempfile_(&tempfile, &tempfilename);
2151                 chain->status = get_equivalent_status_(status);
2152                 return false;
2153         }
2154
2155         /* move the tempfile on top of the original */
2156         (void)fclose(f);
2157         if(!transport_tempfile_(chain->filename, &tempfile, &tempfilename, &status))
2158                 return false;
2159
2160         return true;
2161 }
2162
2163 void simple_iterator_push_(FLAC__Metadata_SimpleIterator *iterator)
2164 {
2165         FLAC__ASSERT(iterator->depth+1 < SIMPLE_ITERATOR_MAX_PUSH_DEPTH);
2166         iterator->offset[iterator->depth+1] = iterator->offset[iterator->depth];
2167         iterator->depth++;
2168 }
2169
2170 FLAC__bool simple_iterator_pop_(FLAC__Metadata_SimpleIterator *iterator)
2171 {
2172         FLAC__ASSERT(iterator->depth > 0);
2173         iterator->depth--;
2174         if(0 != fseek(iterator->file, iterator->offset[iterator->depth], SEEK_SET)) {
2175                 iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_SEEK_ERROR;
2176                 return false;
2177         }
2178
2179         return read_metadata_block_header_(iterator);
2180 }
2181
2182 unsigned seek_to_first_metadata_block_(FILE *f)
2183 {
2184         FLAC__byte buffer[4];
2185         size_t n;
2186         unsigned i;
2187
2188         FLAC__ASSERT(0 != f);
2189         FLAC__ASSERT(FLAC__STREAM_SYNC_LENGTH == 4);
2190
2191         /* skip any id3v2 tag */
2192         errno = 0;
2193         n = fread(buffer, 1, 4, f);
2194         if(errno)
2195                 return 1;
2196         else
2197         if(n != 4)
2198                 return 2;
2199         else if(0 == memcmp(buffer, "ID3", 3)) {
2200                 unsigned tag_length = 0;
2201
2202                 /* skip to the tag length */
2203                 if(fseek(f, 2, SEEK_CUR) < 0)
2204                         return 1;
2205
2206                 /* read the length */
2207                 for(i = 0; i < 4; i++) {
2208                         if(fread(buffer, 1, 1, f) < 1 || buffer[0] & 0x80)
2209                                 return 1;
2210                         tag_length <<= 7;
2211                         tag_length |= (buffer[0] & 0x7f);
2212                 }
2213
2214                 /* skip the rest of the tag */
2215                 if(fseek(f, tag_length, SEEK_CUR) < 0)
2216                         return 1;
2217
2218                 /* read the stream sync code */
2219                 errno = 0;
2220                 n = fread(buffer, 1, 4, f);
2221                 if(errno)
2222                         return 1;
2223                 else
2224                 if(n != 4)
2225                         return 2;
2226         }
2227
2228         /* check for the fLaC signature */
2229         if(0 == memcmp(FLAC__STREAM_SYNC_STRING, buffer, FLAC__STREAM_SYNC_LENGTH))
2230                 return 0;
2231         else
2232                 return 2;
2233 }
2234
2235 FLAC__bool simple_iterator_copy_file_prefix_(FLAC__Metadata_SimpleIterator *iterator, FILE **tempfile, char **tempfilename, FLAC__bool append)
2236 {
2237         const long offset_end = append? iterator->offset[iterator->depth] + (long)FLAC__STREAM_METADATA_HEADER_LENGTH + (long)iterator->length : iterator->offset[iterator->depth];
2238
2239         if(0 != fseek(iterator->file, 0, SEEK_SET)) {
2240                 iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_SEEK_ERROR;
2241                 return false;
2242         }
2243         if(!open_tempfile_(iterator->filename, iterator->tempfile_path_prefix, tempfile, tempfilename, &iterator->status)) {
2244                 cleanup_tempfile_(tempfile, tempfilename);
2245                 return false;
2246         }
2247         if(!copy_n_bytes_from_file_(iterator->file, *tempfile, offset_end, &iterator->status)) {
2248                 cleanup_tempfile_(tempfile, tempfilename);
2249                 return false;
2250         }
2251
2252         return true;
2253 }
2254
2255 FLAC__bool simple_iterator_copy_file_postfix_(FLAC__Metadata_SimpleIterator *iterator, FILE **tempfile, char **tempfilename, int fixup_is_last_code, long fixup_is_last_flag_offset, FLAC__bool backup)
2256 {
2257         long save_offset = iterator->offset[iterator->depth]; /*@@@ 2G limit */
2258         FLAC__ASSERT(0 != *tempfile);
2259
2260         if(0 != fseek(iterator->file, save_offset + FLAC__STREAM_METADATA_HEADER_LENGTH + iterator->length, SEEK_SET)) {
2261                 cleanup_tempfile_(tempfile, tempfilename);
2262                 iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_SEEK_ERROR;
2263                 return false;
2264         }
2265         if(!copy_remaining_bytes_from_file_(iterator->file, *tempfile, &iterator->status)) {
2266                 cleanup_tempfile_(tempfile, tempfilename);
2267                 return false;
2268         }
2269
2270         if(fixup_is_last_code != 0) {
2271                 /*
2272                  * if code == 1, it means a block was appended to the end so
2273                  *   we have to clear the is_last flag of the previous block
2274                  * if code == -1, it means the last block was deleted so
2275                  *   we have to set the is_last flag of the previous block
2276                  */
2277                 /* MAGIC NUMBERs here; we know the is_last flag is the high bit of the byte at this location */
2278                 FLAC__byte x;
2279                 if(0 != fseek(*tempfile, fixup_is_last_flag_offset, SEEK_SET)) {
2280                         cleanup_tempfile_(tempfile, tempfilename);
2281                         iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_SEEK_ERROR;
2282                         return false;
2283                 }
2284                 if(fread(&x, 1, 1, *tempfile) != 1) {
2285                         cleanup_tempfile_(tempfile, tempfilename);
2286                         iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
2287                         return false;
2288                 }
2289                 if(fixup_is_last_code > 0) {
2290                         FLAC__ASSERT(x & 0x80);
2291                         x &= 0x7f;
2292                 }
2293                 else {
2294                         FLAC__ASSERT(!(x & 0x80));
2295                         x |= 0x80;
2296                 }
2297                 if(0 != fseek(*tempfile, fixup_is_last_flag_offset, SEEK_SET)) {
2298                         cleanup_tempfile_(tempfile, tempfilename);
2299                         iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_SEEK_ERROR;
2300                         return false;
2301                 }
2302                 if(local__fwrite(&x, 1, 1, *tempfile) != 1) {
2303                         cleanup_tempfile_(tempfile, tempfilename);
2304                         iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
2305                         return false;
2306                 }
2307         }
2308
2309         (void)fclose(iterator->file);
2310
2311         if(!transport_tempfile_(iterator->filename, tempfile, tempfilename, &iterator->status))
2312                 return false;
2313
2314         if(iterator->has_stats)
2315                 set_file_stats_(iterator->filename, &iterator->stats);
2316
2317         if(!simple_iterator_prime_input_(iterator, !iterator->is_writable))
2318                 return false;
2319         if(backup) {
2320                 while(iterator->offset[iterator->depth] + (long)FLAC__STREAM_METADATA_HEADER_LENGTH + (long)iterator->length < save_offset)
2321                         if(!FLAC__metadata_simple_iterator_next(iterator))
2322                                 return false;
2323                 return true;
2324         }
2325         else {
2326                 /* move the iterator to it's original block faster by faking a push, then doing a pop_ */
2327                 FLAC__ASSERT(iterator->depth == 0);
2328                 iterator->offset[0] = save_offset;
2329                 iterator->depth++;
2330                 return simple_iterator_pop_(iterator);
2331         }
2332 }
2333
2334 FLAC__bool copy_n_bytes_from_file_(FILE *file, FILE *tempfile, unsigned bytes/*@@@ 4G limit*/, FLAC__Metadata_SimpleIteratorStatus *status)
2335 {
2336         FLAC__byte buffer[8192];
2337         unsigned n;
2338
2339         while(bytes > 0) {
2340                 n = min(sizeof(buffer), bytes);
2341                 if(fread(buffer, 1, n, file) != n) {
2342                         *status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
2343                         return false;
2344                 }
2345                 if(local__fwrite(buffer, 1, n, tempfile) != n) {
2346                         *status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
2347                         return false;
2348                 }
2349                 bytes -= n;
2350         }
2351
2352         return true;
2353 }
2354
2355 FLAC__bool copy_remaining_bytes_from_file_(FILE *file, FILE *tempfile, FLAC__Metadata_SimpleIteratorStatus *status)
2356 {
2357         FLAC__byte buffer[8192];
2358         size_t n;
2359
2360         while(!feof(file)) {
2361                 n = fread(buffer, 1, sizeof(buffer), file);
2362                 if(n == 0 && !feof(file)) {
2363                         *status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
2364                         return false;
2365                 }
2366                 if(n > 0 && local__fwrite(buffer, 1, n, tempfile) != n) {
2367                         *status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
2368                         return false;
2369                 }
2370         }
2371
2372         return true;
2373 }
2374
2375 FLAC__bool open_tempfile_(const char *filename, const char *tempfile_path_prefix, FILE **tempfile, char **tempfilename, FLAC__Metadata_SimpleIteratorStatus *status)
2376 {
2377         static const char *tempfile_suffix = ".metadata_edit";
2378         if(0 == tempfile_path_prefix) {
2379                 if(0 == (*tempfilename = (char*)malloc(strlen(filename) + strlen(tempfile_suffix) + 1))) {
2380                         *status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_MEMORY_ALLOCATION_ERROR;
2381                         return false;
2382                 }
2383                 strcpy(*tempfilename, filename);
2384                 strcat(*tempfilename, tempfile_suffix);
2385         }
2386         else {
2387                 const char *p = strrchr(filename, '/');
2388                 if(0 == p)
2389                         p = filename;
2390                 else
2391                         p++;
2392
2393                 if(0 == (*tempfilename = (char*)malloc(strlen(tempfile_path_prefix) + 1 + strlen(p) + strlen(tempfile_suffix) + 1))) {
2394                         *status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_MEMORY_ALLOCATION_ERROR;
2395                         return false;
2396                 }
2397                 strcpy(*tempfilename, tempfile_path_prefix);
2398                 strcat(*tempfilename, "/");
2399                 strcat(*tempfilename, p);
2400                 strcat(*tempfilename, tempfile_suffix);
2401         }
2402
2403         if(0 == (*tempfile = fopen(*tempfilename, "w+b"))) {
2404                 *status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_ERROR_OPENING_FILE;
2405                 return false;
2406         }
2407
2408         return true;
2409 }
2410
2411 FLAC__bool transport_tempfile_(const char *filename, FILE **tempfile, char **tempfilename, FLAC__Metadata_SimpleIteratorStatus *status)
2412 {
2413         FLAC__ASSERT(0 != filename);
2414         FLAC__ASSERT(0 != tempfile);
2415         FLAC__ASSERT(0 != *tempfile);
2416         FLAC__ASSERT(0 != tempfilename);
2417         FLAC__ASSERT(0 != *tempfilename);
2418         FLAC__ASSERT(0 != status);
2419
2420         (void)fclose(*tempfile);
2421         *tempfile = 0;
2422
2423 #if defined _MSC_VER || defined __MINGW32__
2424         if(unlink(filename) < 0) {
2425                 cleanup_tempfile_(tempfile, tempfilename);
2426                 *status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_UNLINK_ERROR;
2427                 return false;
2428         }
2429 #endif
2430
2431         /*@@@ to fully support the tempfile_path_prefix we need to update this piece to actually copy across filesystems instead of just rename(): */
2432         if(0 != rename(*tempfilename, filename)) {
2433                 cleanup_tempfile_(tempfile, tempfilename);
2434                 *status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_RENAME_ERROR;
2435                 return false;
2436         }
2437
2438         cleanup_tempfile_(tempfile, tempfilename);
2439
2440         return true;
2441 }
2442
2443 void cleanup_tempfile_(FILE **tempfile, char **tempfilename)
2444 {
2445         if(0 != *tempfile) {
2446                 (void)fclose(*tempfile);
2447                 *tempfile = 0;
2448         }
2449
2450         if(0 != *tempfilename) {
2451                 (void)unlink(*tempfilename);
2452                 free(*tempfilename);
2453                 *tempfilename = 0;
2454         }
2455 }
2456
2457 FLAC__bool get_file_stats_(const char *filename, struct stat *stats)
2458 {
2459         FLAC__ASSERT(0 != filename);
2460         FLAC__ASSERT(0 != stats);
2461         return (0 == stat(filename, stats));
2462 }
2463
2464 void set_file_stats_(const char *filename, struct stat *stats)
2465 {
2466         struct utimbuf srctime;
2467
2468         FLAC__ASSERT(0 != filename);
2469         FLAC__ASSERT(0 != stats);
2470
2471         srctime.actime = stats->st_atime;
2472         srctime.modtime = stats->st_mtime;
2473         (void)chmod(filename, stats->st_mode);
2474         (void)utime(filename, &srctime);
2475 #if !defined _MSC_VER && !defined __MINGW32__
2476         (void)chown(filename, stats->st_uid, -1);
2477         (void)chown(filename, -1, stats->st_gid);
2478 #endif
2479 }
2480
2481 FLAC__Metadata_ChainStatus get_equivalent_status_(FLAC__Metadata_SimpleIteratorStatus status)
2482 {
2483         switch(status) {
2484                 case FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK:
2485                         return FLAC__METADATA_CHAIN_STATUS_OK;
2486                 case FLAC__METADATA_SIMPLE_ITERATOR_STATUS_ILLEGAL_INPUT:
2487                         return FLAC__METADATA_CHAIN_STATUS_ILLEGAL_INPUT;
2488                 case FLAC__METADATA_SIMPLE_ITERATOR_STATUS_ERROR_OPENING_FILE:
2489                         return FLAC__METADATA_CHAIN_STATUS_ERROR_OPENING_FILE;
2490                 case FLAC__METADATA_SIMPLE_ITERATOR_STATUS_NOT_A_FLAC_FILE:
2491                         return FLAC__METADATA_CHAIN_STATUS_NOT_A_FLAC_FILE;
2492                 case FLAC__METADATA_SIMPLE_ITERATOR_STATUS_NOT_WRITABLE:
2493                         return FLAC__METADATA_CHAIN_STATUS_NOT_WRITABLE;
2494                 case FLAC__METADATA_SIMPLE_ITERATOR_STATUS_BAD_METADATA:
2495                         return FLAC__METADATA_CHAIN_STATUS_BAD_METADATA;
2496                 case FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR:
2497                         return FLAC__METADATA_CHAIN_STATUS_READ_ERROR;
2498                 case FLAC__METADATA_SIMPLE_ITERATOR_STATUS_SEEK_ERROR:
2499                         return FLAC__METADATA_CHAIN_STATUS_SEEK_ERROR;
2500                 case FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR:
2501                         return FLAC__METADATA_CHAIN_STATUS_WRITE_ERROR;
2502                 case FLAC__METADATA_SIMPLE_ITERATOR_STATUS_RENAME_ERROR:
2503                         return FLAC__METADATA_CHAIN_STATUS_RENAME_ERROR;
2504                 case FLAC__METADATA_SIMPLE_ITERATOR_STATUS_UNLINK_ERROR:
2505                         return FLAC__METADATA_CHAIN_STATUS_UNLINK_ERROR;
2506                 case FLAC__METADATA_SIMPLE_ITERATOR_STATUS_MEMORY_ALLOCATION_ERROR:
2507                         return FLAC__METADATA_CHAIN_STATUS_MEMORY_ALLOCATION_ERROR;
2508                 case FLAC__METADATA_SIMPLE_ITERATOR_STATUS_INTERNAL_ERROR:
2509                 default:
2510                         return FLAC__METADATA_CHAIN_STATUS_INTERNAL_ERROR;
2511         }
2512 }