src/libFLAC/metadata_iterators.c

   1 /* libFLAC - Free Lossless Audio Codec library
   2  * Copyright (C) 2001,2002  Josh Coalson
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Library General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Library General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Library General Public
  15  * License along with this library; if not, write to the
  16  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17  * Boston, MA  02111-1307, USA.
  18  */
  19
  20 #if !defined _MSC_VER && !defined __MINGW32__
  21 /*@@@ don't know how to resolve errno without using LIBC.LIB; must use MSVCRT.LIB only for plugins */
  22 #include <errno.h>
  23 #endif
  24 #include <stdio.h>
  25 #include <stdlib.h>
  26 #include <string.h>
  27
  28 #if defined _MSC_VER || defined __MINGW32__
  29 #include <sys/utime.h> /* for utime() */
  30 #include <io.h> /* for chmod() */
  31 #else
  32 #include <sys/types.h> /* some flavors of BSD (like OS X) require this to get time_t */
  33 #include <utime.h> /* for utime() */
  34 #include <unistd.h> /* for chown(), unlink() */
  35 #endif
  36 #include <sys/stat.h> /* for stat(), maybe chmod() */
  37
  38 #include "private/metadata.h"
  39
  40 #include "FLAC/assert.h"
  41 #include "FLAC/file_decoder.h"
  42
  43 #ifdef max
  44 #undef max
  45 #endif
  46 #define max(a,b) ((a)>(b)?(a):(b))
  47 #ifdef min
  48 #undef min
  49 #endif
  50 #define min(a,b) ((a)<(b)?(a):(b))
  51
  52
  53 /****************************************************************************
  54  *
  55  * Local function declarations
  56  *
  57  ***************************************************************************/
  58
  59 static void pack_uint32_(FLAC__uint32 val, FLAC__byte *b, unsigned bytes);
  60 static void pack_uint32_little_endian_(FLAC__uint32 val, FLAC__byte *b, unsigned bytes);
  61 static void pack_uint64_(FLAC__uint64 val, FLAC__byte *b, unsigned bytes);
  62 static FLAC__uint32 unpack_uint32_(FLAC__byte *b, unsigned bytes);
  63 static FLAC__uint32 unpack_uint32_little_endian_(FLAC__byte *b, unsigned bytes);
  64 static FLAC__uint64 unpack_uint64_(FLAC__byte *b, unsigned bytes);
  65
  66 static FLAC__bool read_metadata_block_header_(FLAC__Metadata_SimpleIterator *iterator);
  67 static FLAC__bool read_metadata_block_data_(FLAC__Metadata_SimpleIterator *iterator, FLAC__StreamMetadata *block);
  68 static FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_streaminfo_(FILE *file, FLAC__StreamMetadata_StreamInfo *block);
  69 static FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_padding_(FILE *file, FLAC__StreamMetadata_Padding *block, unsigned block_length);
  70 static FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_application_(FILE *file, FLAC__StreamMetadata_Application *block, unsigned block_length);
  71 static FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_seektable_(FILE *file, FLAC__StreamMetadata_SeekTable *block, unsigned block_length);
  72 static FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_vorbis_comment_entry_(FILE *file, FLAC__StreamMetadata_VorbisComment_Entry *entry);
  73 static FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_vorbis_comment_(FILE *file, FLAC__StreamMetadata_VorbisComment *block);
  74 static FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_cuesheet_track_(FILE *file, FLAC__StreamMetadata_CueSheet_Track *track);
  75 static FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_cuesheet_(FILE *file, FLAC__StreamMetadata_CueSheet *block);
  76
  77 static FLAC__bool write_metadata_block_header_(FILE *file, FLAC__Metadata_SimpleIteratorStatus *status, const FLAC__StreamMetadata *block);
  78 static FLAC__bool write_metadata_block_data_(FILE *file, FLAC__Metadata_SimpleIteratorStatus *status, const FLAC__StreamMetadata *block);
  79 static FLAC__Metadata_SimpleIteratorStatus write_metadata_block_data_streaminfo_(FILE *file, const FLAC__StreamMetadata_StreamInfo *block);
  80 static FLAC__Metadata_SimpleIteratorStatus write_metadata_block_data_padding_(FILE *file, const FLAC__StreamMetadata_Padding *block, unsigned block_length);
  81 static FLAC__Metadata_SimpleIteratorStatus write_metadata_block_data_application_(FILE *file, const FLAC__StreamMetadata_Application *block, unsigned block_length);
  82 static FLAC__Metadata_SimpleIteratorStatus write_metadata_block_data_seektable_(FILE *file, const FLAC__StreamMetadata_SeekTable *block);
  83 static FLAC__Metadata_SimpleIteratorStatus write_metadata_block_data_vorbis_comment_(FILE *file, const FLAC__StreamMetadata_VorbisComment *block);
  84 static FLAC__Metadata_SimpleIteratorStatus write_metadata_block_data_cuesheet_(FILE *file, const FLAC__StreamMetadata_CueSheet *block);
  85 static FLAC__bool write_metadata_block_stationary_(FLAC__Metadata_SimpleIterator *iterator, const FLAC__StreamMetadata *block);
  86 static FLAC__bool write_metadata_block_stationary_with_padding_(FLAC__Metadata_SimpleIterator *iterator, FLAC__StreamMetadata *block, unsigned padding_length, FLAC__bool padding_is_last);
  87 static FLAC__bool rewrite_whole_file_(FLAC__Metadata_SimpleIterator *iterator, FLAC__StreamMetadata *block, FLAC__bool append);
  88
  89 static FLAC__bool chain_rewrite_chain_(FLAC__Metadata_Chain *chain);
  90 static FLAC__bool chain_rewrite_file_(FLAC__Metadata_Chain *chain, const char *tempfile_path_prefix);
  91
  92 static void simple_iterator_push_(FLAC__Metadata_SimpleIterator *iterator);
  93 static FLAC__bool simple_iterator_pop_(FLAC__Metadata_SimpleIterator *iterator);
  94
  95 /* return 0 if OK, 1 if read error, 2 if not a FLAC file */
  96 static unsigned seek_to_first_metadata_block_(FILE *f);
  97
  98 static FLAC__bool simple_iterator_copy_file_prefix_(FLAC__Metadata_SimpleIterator *iterator, FILE **tempfile, char **tempfilename, FLAC__bool append);
  99 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);
 100
 101 static FLAC__bool copy_n_bytes_from_file_(FILE *file, FILE *tempfile, unsigned bytes/*@@@ 4G limit*/, FLAC__Metadata_SimpleIteratorStatus *status);
 102 static FLAC__bool copy_remaining_bytes_from_file_(FILE *file, FILE *tempfile, FLAC__Metadata_SimpleIteratorStatus *status);
 103
 104 static FLAC__bool open_tempfile_(const char *filename, const char *tempfile_path_prefix, FILE **tempfile, char **tempfilename, FLAC__Metadata_SimpleIteratorStatus *status);
 105 static FLAC__bool transport_tempfile_(const char *filename, FILE **tempfile, char **tempfilename, FLAC__Metadata_SimpleIteratorStatus *status);
 106 static void cleanup_tempfile_(FILE **tempfile, char **tempfilename);
 107
 108 static FLAC__bool get_file_stats_(const char *filename, struct stat *stats);
 109 static void set_file_stats_(const char *filename, struct stat *stats);
 110
 111 static FLAC__Metadata_ChainStatus get_equivalent_status_(FLAC__Metadata_SimpleIteratorStatus status);
 112
 113
 114 /****************************************************************************
 115  *
 116  * Level 0 implementation
 117  *
 118  ***************************************************************************/
 119
 120 static FLAC__StreamDecoderWriteStatus write_callback_(const FLAC__FileDecoder *decoder, const FLAC__Frame *frame, const FLAC__int32 * const buffer[], void *client_data);
 121 static void metadata_callback_(const FLAC__FileDecoder *decoder, const FLAC__StreamMetadata *metadata, void *client_data);
 122 static void error_callback_(const FLAC__FileDecoder *decoder, FLAC__StreamDecoderErrorStatus status, void *client_data);
 123
 124 typedef struct {
 125         FLAC__bool got_error;
 126         FLAC__bool got_streaminfo;
 127         FLAC__StreamMetadata *streaminfo;
 128 } level0_client_data;
 129
 130 FLAC_API FLAC__bool FLAC__metadata_get_streaminfo(const char *filename, FLAC__StreamMetadata *streaminfo)
 131 {
 132         level0_client_data cd;
 133         FLAC__FileDecoder *decoder;
 134
 135         FLAC__ASSERT(0 != filename);
 136         FLAC__ASSERT(0 != streaminfo);
 137
 138         decoder = FLAC__file_decoder_new();
 139
 140         if(0 == decoder)
 141                 return false;
 142
 143         cd.got_error = false;
 144         cd.got_streaminfo = false;
 145         cd.streaminfo = streaminfo;
 146
 147         FLAC__file_decoder_set_md5_checking(decoder, false);
 148         FLAC__file_decoder_set_filename(decoder, filename);
 149         FLAC__file_decoder_set_metadata_ignore_all(decoder);
 150         FLAC__file_decoder_set_metadata_respond(decoder, FLAC__METADATA_TYPE_STREAMINFO);
 151         FLAC__file_decoder_set_write_callback(decoder, write_callback_);
 152         FLAC__file_decoder_set_metadata_callback(decoder, metadata_callback_);
 153         FLAC__file_decoder_set_error_callback(decoder, error_callback_);
 154         FLAC__file_decoder_set_client_data(decoder, &cd);
 155
 156         if(FLAC__file_decoder_init(decoder) != FLAC__FILE_DECODER_OK || cd.got_error) {
 157                 FLAC__file_decoder_finish(decoder);
 158                 FLAC__file_decoder_delete(decoder);
 159                 return false;
 160         }
 161
 162         /* the first thing decoded must be the STREAMINFO block: */
 163         if(!FLAC__file_decoder_process_until_end_of_metadata(decoder) || cd.got_error) {
 164                 FLAC__file_decoder_finish(decoder);
 165                 FLAC__file_decoder_delete(decoder);
 166                 return false;
 167         }
 168
 169         FLAC__file_decoder_finish(decoder);
 170         FLAC__file_decoder_delete(decoder);
 171
 172         return !cd.got_error && cd.got_streaminfo;
 173 }
 174
 175 FLAC__StreamDecoderWriteStatus write_callback_(const FLAC__FileDecoder *decoder, const FLAC__Frame *frame, const FLAC__int32 * const buffer[], void *client_data)
 176 {
 177         (void)decoder, (void)frame, (void)buffer, (void)client_data;
 178
 179         return FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE;
 180 }
 181
 182 void metadata_callback_(const FLAC__FileDecoder *decoder, const FLAC__StreamMetadata *metadata, void *client_data)
 183 {
 184         level0_client_data *cd = (level0_client_data *)client_data;
 185         (void)decoder;
 186
 187         if(metadata->type == FLAC__METADATA_TYPE_STREAMINFO && 0 != cd->streaminfo) {
 188                 *(cd->streaminfo) = *metadata;
 189                 cd->got_streaminfo = true;
 190         }
 191 }
 192
 193 void error_callback_(const FLAC__FileDecoder *decoder, FLAC__StreamDecoderErrorStatus status, void *client_data)
 194 {
 195         level0_client_data *cd = (level0_client_data *)client_data;
 196         (void)decoder;
 197
 198         if(status != FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC)
 199                 cd->got_error = true;
 200 }
 201
 202
 203 /****************************************************************************
 204  *
 205  * Level 1 implementation
 206  *
 207  ***************************************************************************/
 208
 209 #define SIMPLE_ITERATOR_MAX_PUSH_DEPTH (1+4)
 210 /* 1 for initial offset, +4 for our own personal use */
 211
 212 struct FLAC__Metadata_SimpleIterator {
 213         FILE *file;
 214         char *filename, *tempfile_path_prefix;
 215         struct stat stats;
 216         FLAC__bool has_stats;
 217         FLAC__bool is_writable;
 218         FLAC__Metadata_SimpleIteratorStatus status;
 219         /*@@@ 2G limits here because of the offset type: */
 220         long offset[SIMPLE_ITERATOR_MAX_PUSH_DEPTH];
 221         long first_offset; /* this is the offset to the STREAMINFO block */
 222         unsigned depth;
 223         /* this is the metadata block header of the current block we are pointing to: */
 224         FLAC__bool is_last;
 225         FLAC__MetadataType type;
 226         unsigned length;
 227 };
 228
 229 FLAC_API const char * const FLAC__Metadata_SimpleIteratorStatusString[] = {
 230         "FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK",
 231         "FLAC__METADATA_SIMPLE_ITERATOR_STATUS_ILLEGAL_INPUT",
 232         "FLAC__METADATA_SIMPLE_ITERATOR_STATUS_ERROR_OPENING_FILE",
 233         "FLAC__METADATA_SIMPLE_ITERATOR_STATUS_NOT_A_FLAC_FILE",
 234         "FLAC__METADATA_SIMPLE_ITERATOR_STATUS_NOT_WRITABLE",
 235         "FLAC__METADATA_SIMPLE_ITERATOR_STATUS_BAD_METADATA",
 236         "FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR",
 237         "FLAC__METADATA_SIMPLE_ITERATOR_STATUS_SEEK_ERROR",
 238         "FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR",
 239         "FLAC__METADATA_SIMPLE_ITERATOR_STATUS_RENAME_ERROR",
 240         "FLAC__METADATA_SIMPLE_ITERATOR_STATUS_UNLINK_ERROR",
 241         "FLAC__METADATA_SIMPLE_ITERATOR_STATUS_MEMORY_ALLOCATION_ERROR",
 242         "FLAC__METADATA_SIMPLE_ITERATOR_STATUS_INTERNAL_ERROR"
 243 };
 244
 245
 246 FLAC_API FLAC__Metadata_SimpleIterator *FLAC__metadata_simple_iterator_new()
 247 {
 248         FLAC__Metadata_SimpleIterator *iterator = (FLAC__Metadata_SimpleIterator*)calloc(1, sizeof(FLAC__Metadata_SimpleIterator));
 249
 250         if(0 != iterator) {
 251                 iterator->file = 0;
 252                 iterator->filename = 0;
 253                 iterator->tempfile_path_prefix = 0;
 254                 iterator->has_stats = false;
 255                 iterator->is_writable = false;
 256                 iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK;
 257                 iterator->first_offset = iterator->offset[0] = -1;
 258                 iterator->depth = 0;
 259         }
 260
 261         return iterator;
 262 }
 263
 264 static void simple_iterator_free_guts_(FLAC__Metadata_SimpleIterator *iterator)
 265 {
 266         FLAC__ASSERT(0 != iterator);
 267
 268         if(0 != iterator->file) {
 269                 fclose(iterator->file);
 270                 iterator->file = 0;
 271                 if(iterator->has_stats)
 272                         set_file_stats_(iterator->filename, &iterator->stats);
 273         }
 274         if(0 != iterator->filename) {
 275                 free(iterator->filename);
 276                 iterator->filename = 0;
 277         }
 278         if(0 != iterator->tempfile_path_prefix) {
 279                 free(iterator->tempfile_path_prefix);
 280                 iterator->tempfile_path_prefix = 0;
 281         }
 282 }
 283
 284 FLAC_API void FLAC__metadata_simple_iterator_delete(FLAC__Metadata_SimpleIterator *iterator)
 285 {
 286         FLAC__ASSERT(0 != iterator);
 287
 288         simple_iterator_free_guts_(iterator);
 289         free(iterator);
 290 }
 291
 292 FLAC_API FLAC__Metadata_SimpleIteratorStatus FLAC__metadata_simple_iterator_status(FLAC__Metadata_SimpleIterator *iterator)
 293 {
 294         FLAC__Metadata_SimpleIteratorStatus status;
 295
 296         FLAC__ASSERT(0 != iterator);
 297
 298         status = iterator->status;
 299         iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK;
 300         return status;
 301 }
 302
 303 static FLAC__bool simple_iterator_prime_input_(FLAC__Metadata_SimpleIterator *iterator, FLAC__bool read_only)
 304 {
 305         unsigned ret;
 306
 307         FLAC__ASSERT(0 != iterator);
 308
 309         if(read_only || 0 == (iterator->file = fopen(iterator->filename, "r+b"))) {
 310                 iterator->is_writable = false;
 311 #if !defined _MSC_VER && !defined __MINGW32__
 312 /*@@@ don't know how to resolve errno without using LIBC.LIB; must use MSVCRT.LIB only for plugins */
 313                 if(read_only || errno == EACCES) {
 314 #endif
 315                         if(0 == (iterator->file = fopen(iterator->filename, "rb"))) {
 316                                 iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_ERROR_OPENING_FILE;
 317                                 return false;
 318                         }
 319 #if !defined _MSC_VER && !defined __MINGW32__
 320                 }
 321                 else {
 322                         iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_ERROR_OPENING_FILE;
 323                         return false;
 324                 }
 325 #endif
 326         }
 327         else {
 328                 iterator->is_writable = true;
 329         }
 330
 331         ret = seek_to_first_metadata_block_(iterator->file);
 332         switch(ret) {
 333                 case 0:
 334                         iterator->depth = 0;
 335                         iterator->first_offset = iterator->offset[iterator->depth] = ftell(iterator->file);
 336                         return read_metadata_block_header_(iterator);
 337                 case 1:
 338                         iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
 339                         return false;
 340                 case 2:
 341                         iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_NOT_A_FLAC_FILE;
 342                         return false;
 343                 default:
 344                         FLAC__ASSERT(0);
 345                         return false;
 346         }
 347 }
 348
 349 #if 0
 350 @@@ If we decide to finish implementing this, put this comment back in metadata.h
 351 /*
 352  * The 'tempfile_path_prefix' allows you to specify a directory where
 353  * tempfiles should go.  Remember that if your metadata edits cause the
 354  * FLAC file to grow, the entire file will have to be rewritten.  If
 355  * 'tempfile_path_prefix' is NULL, the temp file will be written in the
 356  * same directory as the original FLAC file.  This makes replacing the
 357  * original with the tempfile fast but requires extra space in the same
 358  * partition for the tempfile.  If space is a problem, you can pass a
 359  * directory name belonging to a different partition in
 360  * 'tempfile_path_prefix'.  Note that you should use the forward slash
 361  * '/' as the directory separator.  A trailing slash is not needed; it
 362  * will be added automatically.
 363  */
 364 FLAC__bool FLAC__metadata_simple_iterator_init(FLAC__Metadata_SimpleIterator *iterator, const char *filename, FLAC__bool preserve_file_stats, const char *tempfile_path_prefix);
 365 #endif
 366
 367 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)
 368 {
 369         const char *tempfile_path_prefix = 0; /*@@@ search for comments near 'rename(...)' for what it will take to finish implementing this */
 370
 371         FLAC__ASSERT(0 != iterator);
 372         FLAC__ASSERT(0 != filename);
 373
 374         simple_iterator_free_guts_(iterator);
 375
 376         if(!read_only && preserve_file_stats)
 377                 iterator->has_stats = get_file_stats_(filename, &iterator->stats);
 378
 379         if(0 == (iterator->filename = strdup(filename))) {
 380                 iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_MEMORY_ALLOCATION_ERROR;
 381                 return false;
 382         }
 383         if(0 != tempfile_path_prefix && 0 == (iterator->tempfile_path_prefix = strdup(tempfile_path_prefix))) {
 384                 iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_MEMORY_ALLOCATION_ERROR;
 385                 return false;
 386         }
 387
 388         return simple_iterator_prime_input_(iterator, read_only);
 389 }
 390
 391 FLAC_API FLAC__bool FLAC__metadata_simple_iterator_is_writable(const FLAC__Metadata_SimpleIterator *iterator)
 392 {
 393         FLAC__ASSERT(0 != iterator);
 394         FLAC__ASSERT(0 != iterator->file);
 395
 396         return iterator->is_writable;
 397 }
 398
 399 FLAC_API FLAC__bool FLAC__metadata_simple_iterator_next(FLAC__Metadata_SimpleIterator *iterator)
 400 {
 401         FLAC__ASSERT(0 != iterator);
 402         FLAC__ASSERT(0 != iterator->file);
 403
 404         if(iterator->is_last)
 405                 return false;
 406
 407         if(0 != fseek(iterator->file, iterator->length, SEEK_CUR)) {
 408                 iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_SEEK_ERROR;
 409                 return false;
 410         }
 411
 412         iterator->offset[iterator->depth] = ftell(iterator->file);
 413
 414         return read_metadata_block_header_(iterator);
 415 }
 416
 417 FLAC_API FLAC__bool FLAC__metadata_simple_iterator_prev(FLAC__Metadata_SimpleIterator *iterator)
 418 {
 419         long this_offset;
 420
 421         FLAC__ASSERT(0 != iterator);
 422         FLAC__ASSERT(0 != iterator->file);
 423
 424         if(iterator->offset[iterator->depth] == iterator->first_offset)
 425                 return false;
 426
 427         if(0 != fseek(iterator->file, iterator->first_offset, SEEK_SET)) {
 428                 iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_SEEK_ERROR;
 429                 return false;
 430         }
 431         this_offset = iterator->first_offset;
 432         if(!read_metadata_block_header_(iterator))
 433                 return false;
 434
 435         /* we ignore any error from ftell() and catch it in fseek() */
 436         while(ftell(iterator->file) + (long)iterator->length < iterator->offset[iterator->depth]) {
 437                 if(0 != fseek(iterator->file, iterator->length, SEEK_CUR)) {
 438                         iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_SEEK_ERROR;
 439                         return false;
 440                 }
 441                 this_offset = ftell(iterator->file);
 442                 if(!read_metadata_block_header_(iterator))
 443                         return false;
 444         }
 445
 446         iterator->offset[iterator->depth] = this_offset;
 447
 448         return true;
 449 }
 450
 451 FLAC_API FLAC__MetadataType FLAC__metadata_simple_iterator_get_block_type(const FLAC__Metadata_SimpleIterator *iterator)
 452 {
 453         FLAC__ASSERT(0 != iterator);
 454         FLAC__ASSERT(0 != iterator->file);
 455
 456         return iterator->type;
 457 }
 458
 459 FLAC_API FLAC__StreamMetadata *FLAC__metadata_simple_iterator_get_block(FLAC__Metadata_SimpleIterator *iterator)
 460 {
 461         FLAC__StreamMetadata *block = FLAC__metadata_object_new(iterator->type);
 462
 463         FLAC__ASSERT(0 != iterator);
 464         FLAC__ASSERT(0 != iterator->file);
 465
 466         if(0 != block) {
 467                 block->is_last = iterator->is_last;
 468                 block->length = iterator->length;
 469
 470                 if(!read_metadata_block_data_(iterator, block)) {
 471                         FLAC__metadata_object_delete(block);
 472                         return 0;
 473                 }
 474
 475                 /* back up to the beginning of the block data to stay consistent */
 476                 if(0 != fseek(iterator->file, iterator->offset[iterator->depth] + FLAC__STREAM_METADATA_HEADER_LENGTH, SEEK_SET)) {
 477                         iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_SEEK_ERROR;
 478                         FLAC__metadata_object_delete(block);
 479                         return 0;
 480                 }
 481         }
 482         else
 483                 iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_MEMORY_ALLOCATION_ERROR;
 484
 485         return block;
 486 }
 487
 488 FLAC_API FLAC__bool FLAC__metadata_simple_iterator_set_block(FLAC__Metadata_SimpleIterator *iterator, FLAC__StreamMetadata *block, FLAC__bool use_padding)
 489 {
 490         FLAC__ASSERT_DECLARATION(long debug_target_offset = iterator->offset[iterator->depth];)
 491         FLAC__bool ret;
 492
 493         FLAC__ASSERT(0 != iterator);
 494         FLAC__ASSERT(0 != iterator->file);
 495         FLAC__ASSERT(0 != block);
 496
 497         if(!iterator->is_writable) {
 498                 iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_NOT_WRITABLE;
 499                 return false;
 500         }
 501
 502         if(iterator->type == FLAC__METADATA_TYPE_STREAMINFO || block->type == FLAC__METADATA_TYPE_STREAMINFO) {
 503                 if(iterator->type != block->type) {
 504                         iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_ILLEGAL_INPUT;
 505                         return false;
 506                 }
 507         }
 508
 509         block->is_last = iterator->is_last;
 510
 511         if(iterator->length == block->length)
 512                 return write_metadata_block_stationary_(iterator, block);
 513         else if(iterator->length > block->length) {
 514                 if(use_padding && iterator->length >= FLAC__STREAM_METADATA_HEADER_LENGTH + block->length) {
 515                         ret =  write_metadata_block_stationary_with_padding_(iterator, block, iterator->length - FLAC__STREAM_METADATA_HEADER_LENGTH - block->length, block->is_last);
 516                         FLAC__ASSERT(iterator->offset[iterator->depth] == debug_target_offset);
 517                         FLAC__ASSERT(ftell(iterator->file) == debug_target_offset + (long)FLAC__STREAM_METADATA_HEADER_LENGTH);
 518                         return ret;
 519                 }
 520                 else {
 521                         ret = rewrite_whole_file_(iterator, block, /*append=*/false);
 522                         FLAC__ASSERT(iterator->offset[iterator->depth] == debug_target_offset);
 523                         FLAC__ASSERT(ftell(iterator->file) == debug_target_offset + (long)FLAC__STREAM_METADATA_HEADER_LENGTH);
 524                         return ret;
 525                 }
 526         }
 527         else /* iterator->length < block->length */ {
 528                 unsigned padding_leftover = 0;
 529                 FLAC__bool padding_is_last = false;
 530                 if(use_padding) {
 531                         /* first see if we can even use padding */
 532                         if(iterator->is_last) {
 533                                 use_padding = false;
 534                         }
 535                         else {
 536                                 const unsigned extra_padding_bytes_required = block->length - iterator->length;
 537                                 simple_iterator_push_(iterator);
 538                                 if(!FLAC__metadata_simple_iterator_next(iterator)) {
 539                                         (void)simple_iterator_pop_(iterator);
 540                                         return false;
 541                                 }
 542                                 if(iterator->type != FLAC__METADATA_TYPE_PADDING) {
 543                                         use_padding = false;
 544                                 }
 545                                 else {
 546                                         if(FLAC__STREAM_METADATA_HEADER_LENGTH + iterator->length == extra_padding_bytes_required) {
 547                                                 padding_leftover = 0;
 548                                                 block->is_last = iterator->is_last;
 549                                         }
 550                                         else if(iterator->length < extra_padding_bytes_required)
 551                                                 use_padding = false;
 552                                         else {
 553                                                 padding_leftover = FLAC__STREAM_METADATA_HEADER_LENGTH + iterator->length - extra_padding_bytes_required;
 554                                                 padding_is_last = iterator->is_last;
 555                                                 block->is_last = false;
 556                                         }
 557                                 }
 558                                 if(!simple_iterator_pop_(iterator))
 559                                         return false;
 560                         }
 561                 }
 562                 if(use_padding) {
 563                         if(padding_leftover == 0) {
 564                                 ret = write_metadata_block_stationary_(iterator, block);
 565                                 FLAC__ASSERT(iterator->offset[iterator->depth] == debug_target_offset);
 566                                 FLAC__ASSERT(ftell(iterator->file) == debug_target_offset + (long)FLAC__STREAM_METADATA_HEADER_LENGTH);
 567                                 return ret;
 568                         }
 569                         else {
 570                                 FLAC__ASSERT(padding_leftover >= FLAC__STREAM_METADATA_HEADER_LENGTH);
 571                                 ret = write_metadata_block_stationary_with_padding_(iterator, block, padding_leftover - FLAC__STREAM_METADATA_HEADER_LENGTH, padding_is_last);
 572                                 FLAC__ASSERT(iterator->offset[iterator->depth] == debug_target_offset);
 573                                 FLAC__ASSERT(ftell(iterator->file) == debug_target_offset + (long)FLAC__STREAM_METADATA_HEADER_LENGTH);
 574                                 return ret;
 575                         }
 576                 }
 577                 else {
 578                         ret = rewrite_whole_file_(iterator, block, /*append=*/false);
 579                         FLAC__ASSERT(iterator->offset[iterator->depth] == debug_target_offset);
 580                         FLAC__ASSERT(ftell(iterator->file) == debug_target_offset + (long)FLAC__STREAM_METADATA_HEADER_LENGTH);
 581                         return ret;
 582                 }
 583         }
 584 }
 585
 586 FLAC_API FLAC__bool FLAC__metadata_simple_iterator_insert_block_after(FLAC__Metadata_SimpleIterator *iterator, FLAC__StreamMetadata *block, FLAC__bool use_padding)
 587 {
 588         unsigned padding_leftover = 0;
 589         FLAC__bool padding_is_last = false;
 590
 591         FLAC__ASSERT_DECLARATION(long debug_target_offset = iterator->offset[iterator->depth] + FLAC__STREAM_METADATA_HEADER_LENGTH + iterator->length;)
 592         FLAC__bool ret;
 593
 594         FLAC__ASSERT(0 != iterator);
 595         FLAC__ASSERT(0 != iterator->file);
 596         FLAC__ASSERT(0 != block);
 597
 598         if(!iterator->is_writable)
 599                 return false;
 600
 601         if(block->type == FLAC__METADATA_TYPE_STREAMINFO) {
 602                 iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_ILLEGAL_INPUT;
 603                 return false;
 604         }
 605
 606         block->is_last = iterator->is_last;
 607
 608         if(use_padding) {
 609                 /* first see if we can even use padding */
 610                 if(iterator->is_last) {
 611                         use_padding = false;
 612                 }
 613                 else {
 614                         simple_iterator_push_(iterator);
 615                         if(!FLAC__metadata_simple_iterator_next(iterator)) {
 616                                 (void)simple_iterator_pop_(iterator);
 617                                 return false;
 618                         }
 619                         if(iterator->type != FLAC__METADATA_TYPE_PADDING) {
 620                                 use_padding = false;
 621                         }
 622                         else {
 623                                 if(iterator->length == block->length) {
 624                                         padding_leftover = 0;
 625                                         block->is_last = iterator->is_last;
 626                                 }
 627                                 else if(iterator->length < FLAC__STREAM_METADATA_HEADER_LENGTH + block->length)
 628                                         use_padding = false;
 629                                 else {
 630                                         padding_leftover = iterator->length - block->length;
 631                                         padding_is_last = iterator->is_last;
 632                                         block->is_last = false;
 633                                 }
 634                         }
 635                         if(!simple_iterator_pop_(iterator))
 636                                 return false;
 637                 }
 638         }
 639         if(use_padding) {
 640                 /* move to the next block, which is suitable padding */
 641                 if(!FLAC__metadata_simple_iterator_next(iterator))
 642                         return false;
 643                 if(padding_leftover == 0) {
 644                         ret = write_metadata_block_stationary_(iterator, block);
 645                         FLAC__ASSERT(iterator->offset[iterator->depth] == debug_target_offset);
 646                         FLAC__ASSERT(ftell(iterator->file) == debug_target_offset + (long)FLAC__STREAM_METADATA_HEADER_LENGTH);
 647                         return ret;
 648                 }
 649                 else {
 650                         FLAC__ASSERT(padding_leftover >= FLAC__STREAM_METADATA_HEADER_LENGTH);
 651                         ret = write_metadata_block_stationary_with_padding_(iterator, block, padding_leftover - FLAC__STREAM_METADATA_HEADER_LENGTH, padding_is_last);
 652                         FLAC__ASSERT(iterator->offset[iterator->depth] == debug_target_offset);
 653                         FLAC__ASSERT(ftell(iterator->file) == debug_target_offset + (long)FLAC__STREAM_METADATA_HEADER_LENGTH);
 654                         return ret;
 655                 }
 656         }
 657         else {
 658                 ret = rewrite_whole_file_(iterator, block, /*append=*/true);
 659                 FLAC__ASSERT(iterator->offset[iterator->depth] == debug_target_offset);
 660                 FLAC__ASSERT(ftell(iterator->file) == debug_target_offset + (long)FLAC__STREAM_METADATA_HEADER_LENGTH);
 661                 return ret;
 662         }
 663 }
 664
 665 FLAC_API FLAC__bool FLAC__metadata_simple_iterator_delete_block(FLAC__Metadata_SimpleIterator *iterator, FLAC__bool use_padding)
 666 {
 667         FLAC__ASSERT_DECLARATION(long debug_target_offset = iterator->offset[iterator->depth];)
 668         FLAC__bool ret;
 669
 670         if(iterator->type == FLAC__METADATA_TYPE_STREAMINFO) {
 671                 iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_ILLEGAL_INPUT;
 672                 return false;
 673         }
 674
 675         if(use_padding) {
 676                 FLAC__StreamMetadata *padding = FLAC__metadata_object_new(FLAC__METADATA_TYPE_PADDING);
 677                 if(0 == padding) {
 678                         iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_MEMORY_ALLOCATION_ERROR;
 679                         return false;
 680                 }
 681                 padding->length = iterator->length;
 682                 if(!FLAC__metadata_simple_iterator_set_block(iterator, padding, false)) {
 683                         FLAC__metadata_object_delete(padding);
 684                         return false;
 685                 }
 686                 FLAC__metadata_object_delete(padding);
 687                 if(!FLAC__metadata_simple_iterator_prev(iterator))
 688                         return false;
 689                 FLAC__ASSERT(iterator->offset[iterator->depth] + (long)FLAC__STREAM_METADATA_HEADER_LENGTH + (long)iterator->length == debug_target_offset);
 690                 FLAC__ASSERT(ftell(iterator->file) + (long)iterator->length == debug_target_offset);
 691                 return true;
 692         }
 693         else {
 694                 ret = rewrite_whole_file_(iterator, 0, /*append=*/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 ret;
 698         }
 699 }
 700
 701
 702
 703 /****************************************************************************
 704  *
 705  * Level 2 implementation
 706  *
 707  ***************************************************************************/
 708
 709
 710 typedef struct FLAC__Metadata_Node {
 711         FLAC__StreamMetadata *data;
 712         struct FLAC__Metadata_Node *prev, *next;
 713 } FLAC__Metadata_Node;
 714
 715 struct FLAC__Metadata_Chain {
 716         char *filename;
 717         FLAC__Metadata_Node *head;
 718         FLAC__Metadata_Node *tail;
 719         unsigned nodes;
 720         FLAC__Metadata_ChainStatus status;
 721         long first_offset, last_offset; /*@@@ 2G limit */
 722         /*
 723          * This is the length of the chain initially read from the FLAC file.
 724          * it is used to compare against the current length to decide whether
 725          * or not the whole file has to be rewritten.
 726          */
 727         unsigned initial_length; /*@@@ 4G limit */
 728 };
 729
 730 struct FLAC__Metadata_Iterator {
 731         FLAC__Metadata_Chain *chain;
 732         FLAC__Metadata_Node *current;
 733 };
 734
 735 FLAC_API const char * const FLAC__Metadata_ChainStatusString[] = {
 736         "FLAC__METADATA_CHAIN_STATUS_OK",
 737         "FLAC__METADATA_CHAIN_STATUS_ILLEGAL_INPUT",
 738         "FLAC__METADATA_CHAIN_STATUS_ERROR_OPENING_FILE",
 739         "FLAC__METADATA_CHAIN_STATUS_NOT_A_FLAC_FILE",
 740         "FLAC__METADATA_CHAIN_STATUS_NOT_WRITABLE",
 741         "FLAC__METADATA_CHAIN_STATUS_BAD_METADATA",
 742         "FLAC__METADATA_CHAIN_STATUS_READ_ERROR",
 743         "FLAC__METADATA_CHAIN_STATUS_SEEK_ERROR",
 744         "FLAC__METADATA_CHAIN_STATUS_WRITE_ERROR",
 745         "FLAC__METADATA_CHAIN_STATUS_RENAME_ERROR",
 746         "FLAC__METADATA_CHAIN_STATUS_UNLINK_ERROR",
 747         "FLAC__METADATA_CHAIN_STATUS_MEMORY_ALLOCATION_ERROR",
 748         "FLAC__METADATA_CHAIN_STATUS_INTERNAL_ERROR"
 749 };
 750
 751
 752 static FLAC__Metadata_Node *node_new_()
 753 {
 754         return (FLAC__Metadata_Node*)calloc(1, sizeof(FLAC__Metadata_Node));
 755 }
 756
 757 static void node_delete_(FLAC__Metadata_Node *node)
 758 {
 759         FLAC__ASSERT(0 != node);
 760         if(0 != node->data)
 761                 FLAC__metadata_object_delete(node->data);
 762         free(node);
 763 }
 764
 765 static void chain_append_node_(FLAC__Metadata_Chain *chain, FLAC__Metadata_Node *node)
 766 {
 767         FLAC__ASSERT(0 != chain);
 768         FLAC__ASSERT(0 != node);
 769         FLAC__ASSERT(0 != node->data);
 770
 771         node->next = node->prev = 0;
 772         node->data->is_last = true;
 773         if(0 != chain->tail)
 774                 chain->tail->data->is_last = false;
 775
 776         if(0 == chain->head)
 777                 chain->head = node;
 778         else {
 779                 FLAC__ASSERT(0 != chain->tail);
 780                 chain->tail->next = node;
 781                 node->prev = chain->tail;
 782         }
 783         chain->tail = node;
 784         chain->nodes++;
 785 }
 786
 787 static void chain_remove_node_(FLAC__Metadata_Chain *chain, FLAC__Metadata_Node *node)
 788 {
 789         FLAC__ASSERT(0 != chain);
 790         FLAC__ASSERT(0 != node);
 791
 792         if(node == chain->head)
 793                 chain->head = node->next;
 794         else
 795                 node->prev->next = node->next;
 796
 797         if(node == chain->tail)
 798                 chain->tail = node->prev;
 799         else
 800                 node->next->prev = node->prev;
 801
 802         if(0 != chain->tail)
 803                 chain->tail->data->is_last = true;
 804
 805         chain->nodes--;
 806 }
 807
 808 static void chain_delete_node_(FLAC__Metadata_Chain *chain, FLAC__Metadata_Node *node)
 809 {
 810         chain_remove_node_(chain, node);
 811         node_delete_(node);
 812 }
 813
 814 static unsigned chain_calculate_length_(FLAC__Metadata_Chain *chain)
 815 {
 816         const FLAC__Metadata_Node *node;
 817         unsigned length = 0;
 818         for(node = chain->head; node; node = node->next)
 819                 length += (FLAC__STREAM_METADATA_HEADER_LENGTH + node->data->length);
 820         return length;
 821 }
 822
 823 static void iterator_insert_node_(FLAC__Metadata_Iterator *iterator, FLAC__Metadata_Node *node)
 824 {
 825         FLAC__ASSERT(0 != node);
 826         FLAC__ASSERT(0 != node->data);
 827         FLAC__ASSERT(0 != iterator);
 828         FLAC__ASSERT(0 != iterator->current);
 829         FLAC__ASSERT(0 != iterator->chain);
 830         FLAC__ASSERT(0 != iterator->chain->head);
 831         FLAC__ASSERT(0 != iterator->chain->tail);
 832
 833         node->data->is_last = false;
 834
 835         node->prev = iterator->current->prev;
 836         node->next = iterator->current;
 837
 838         if(0 == node->prev)
 839                 iterator->chain->head = node;
 840         else
 841                 node->prev->next = node;
 842
 843         iterator->current->prev = node;
 844
 845         iterator->chain->nodes++;
 846 }
 847
 848 static void iterator_insert_node_after_(FLAC__Metadata_Iterator *iterator, FLAC__Metadata_Node *node)
 849 {
 850         FLAC__ASSERT(0 != node);
 851         FLAC__ASSERT(0 != node->data);
 852         FLAC__ASSERT(0 != iterator);
 853         FLAC__ASSERT(0 != iterator->current);
 854         FLAC__ASSERT(0 != iterator->chain);
 855         FLAC__ASSERT(0 != iterator->chain->head);
 856         FLAC__ASSERT(0 != iterator->chain->tail);
 857
 858         iterator->current->data->is_last = false;
 859
 860         node->prev = iterator->current;
 861         node->next = iterator->current->next;
 862
 863         if(0 == node->next)
 864                 iterator->chain->tail = node;
 865         else
 866                 node->next->prev = node;
 867
 868         node->prev->next = node;
 869
 870         iterator->chain->tail->data->is_last = true;
 871
 872         iterator->chain->nodes++;
 873 }
 874
 875 /* return true iff node and node->next are both padding */
 876 static FLAC__bool chain_merge_adjacent_padding_(FLAC__Metadata_Chain *chain, FLAC__Metadata_Node *node)
 877 {
 878         if(node->data->type == FLAC__METADATA_TYPE_PADDING && 0 != node->next && node->next->data->type == FLAC__METADATA_TYPE_PADDING) {
 879                 const unsigned growth = FLAC__STREAM_METADATA_HEADER_LENGTH + node->next->data->length;
 880                 node->data->length += growth;
 881
 882                 chain_delete_node_(chain, node->next);
 883                 return true;
 884         }
 885         else
 886                 return false;
 887 }
 888
 889 FLAC_API FLAC__Metadata_Chain *FLAC__metadata_chain_new()
 890 {
 891         FLAC__Metadata_Chain *chain = (FLAC__Metadata_Chain*)calloc(1, sizeof(FLAC__Metadata_Chain));
 892
 893         if(0 != chain) {
 894                 chain->filename = 0;
 895                 chain->head = chain->tail = 0;
 896                 chain->nodes = 0;
 897                 chain->status = FLAC__METADATA_CHAIN_STATUS_OK;
 898                 chain->initial_length = 0;
 899         }
 900
 901         return chain;
 902 }
 903
 904 FLAC_API void FLAC__metadata_chain_delete(FLAC__Metadata_Chain *chain)
 905 {
 906         FLAC__Metadata_Node *node, *next;
 907
 908         FLAC__ASSERT(0 != chain);
 909
 910         for(node = chain->head; node; ) {
 911                 next = node->next;
 912                 node_delete_(node);
 913                 node = next;
 914         }
 915
 916         if(0 != chain->filename)
 917                 free(chain->filename);
 918
 919         free(chain);
 920 }
 921
 922 FLAC_API FLAC__Metadata_ChainStatus FLAC__metadata_chain_status(FLAC__Metadata_Chain *chain)
 923 {
 924         FLAC__Metadata_ChainStatus status;
 925
 926         FLAC__ASSERT(0 != chain);
 927
 928         status = chain->status;
 929         chain->status = FLAC__METADATA_CHAIN_STATUS_OK;
 930         return status;
 931 }
 932
 933 FLAC_API FLAC__bool FLAC__metadata_chain_read(FLAC__Metadata_Chain *chain, const char *filename)
 934 {
 935         FLAC__Metadata_SimpleIterator *iterator;
 936         FLAC__Metadata_Node *node;
 937
 938         FLAC__ASSERT(0 != chain);
 939         FLAC__ASSERT(0 != filename);
 940
 941         if(0 == (chain->filename = strdup(filename))) {
 942                 chain->status = FLAC__METADATA_CHAIN_STATUS_MEMORY_ALLOCATION_ERROR;
 943                 return false;
 944         }
 945
 946         if(0 == (iterator = FLAC__metadata_simple_iterator_new())) {
 947                 chain->status = FLAC__METADATA_CHAIN_STATUS_MEMORY_ALLOCATION_ERROR;
 948                 return false;
 949         }
 950
 951         if(!FLAC__metadata_simple_iterator_init(iterator, filename, /*read_only=*/true, /*preserve_file_stats=*/false)) {
 952                 chain->status = get_equivalent_status_(iterator->status);
 953                 return false;
 954         }
 955
 956         chain->first_offset = iterator->offset[iterator->depth];
 957
 958         do {
 959                 node = node_new_();
 960                 if(0 == node) {
 961                         chain->status = FLAC__METADATA_CHAIN_STATUS_MEMORY_ALLOCATION_ERROR;
 962                         return false;
 963                 }
 964                 node->data = FLAC__metadata_simple_iterator_get_block(iterator);
 965                 if(0 == node->data) {
 966                         node_delete_(node);
 967                         chain->status = get_equivalent_status_(iterator->status);
 968                         return false;
 969                 }
 970                 chain_append_node_(chain, node);
 971         } while(FLAC__metadata_simple_iterator_next(iterator));
 972
 973         if(!iterator->is_last || iterator->status != FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK) {
 974                 chain->status = get_equivalent_status_(iterator->status);
 975                 return false;
 976         }
 977
 978         chain->last_offset = ftell(iterator->file) + iterator->length;
 979         FLAC__metadata_simple_iterator_delete(iterator);
 980
 981         chain->initial_length = chain_calculate_length_(chain);
 982         return true;
 983 }
 984
 985 FLAC_API FLAC__bool FLAC__metadata_chain_write(FLAC__Metadata_Chain *chain, FLAC__bool use_padding, FLAC__bool preserve_file_stats)
 986 {
 987         struct stat stats;
 988         const char *tempfile_path_prefix = 0;
 989         unsigned current_length;
 990
 991         FLAC__ASSERT(0 != chain);
 992
 993         current_length = chain_calculate_length_(chain);
 994
 995         if(use_padding) {
 996                 if(current_length < chain->initial_length && chain->tail->data->type == FLAC__METADATA_TYPE_PADDING) {
 997                         const unsigned delta = chain->initial_length - current_length;
 998                         chain->tail->data->length += delta;
 999                         current_length += delta;
1000                         FLAC__ASSERT(current_length == chain->initial_length);
1001                 }
1002                 else if(current_length + FLAC__STREAM_METADATA_HEADER_LENGTH <= chain->initial_length) {
1003                         FLAC__StreamMetadata *padding;
1004                         FLAC__Metadata_Node *node;
1005                         if(0 == (padding = FLAC__metadata_object_new(FLAC__METADATA_TYPE_PADDING))) {
1006                                 chain->status = FLAC__METADATA_CHAIN_STATUS_MEMORY_ALLOCATION_ERROR;
1007                                 return false;
1008                         }
1009                         padding->length = chain->initial_length - (FLAC__STREAM_METADATA_HEADER_LENGTH + current_length);
1010                         if(0 == (node = node_new_())) {
1011                                 FLAC__metadata_object_delete(padding);
1012                                 chain->status = FLAC__METADATA_CHAIN_STATUS_MEMORY_ALLOCATION_ERROR;
1013                                 return false;
1014                         }
1015                         node->data = padding;
1016                         chain_append_node_(chain, node);
1017                         current_length = chain_calculate_length_(chain);
1018                         FLAC__ASSERT(current_length == chain->initial_length);
1019                 }
1020                 else if(current_length > chain->initial_length) {
1021                         const unsigned delta = current_length - chain->initial_length;
1022                         if(chain->tail->data->type == FLAC__METADATA_TYPE_PADDING) {
1023                                 if(chain->tail->data->length + FLAC__STREAM_METADATA_HEADER_LENGTH == delta) {
1024                                         chain_delete_node_(chain, chain->tail);
1025                                         current_length = chain_calculate_length_(chain);
1026                                         FLAC__ASSERT(current_length == chain->initial_length);
1027                                 }
1028                                 else if(chain->tail->data->length >= delta) {
1029                                         chain->tail->data->length -= delta;
1030                                         current_length -= delta;
1031                                         FLAC__ASSERT(current_length == chain->initial_length);
1032                                 }
1033                         }
1034                 }
1035         }
1036
1037         if(preserve_file_stats)
1038                 get_file_stats_(chain->filename, &stats);
1039
1040         if(current_length == chain->initial_length) {
1041                 if(!chain_rewrite_chain_(chain))
1042                         return false;
1043         }
1044         else {
1045                 if(!chain_rewrite_file_(chain, tempfile_path_prefix))
1046                         return false;
1047         }
1048
1049         if(preserve_file_stats)
1050                 set_file_stats_(chain->filename, &stats);
1051
1052         /* recompute lengths and offsets if necessary */
1053         if(chain->initial_length != current_length) {
1054                 const FLAC__Metadata_Node *node;
1055                 chain->initial_length = current_length;
1056                 chain->last_offset = chain->first_offset;
1057                 for(node = chain->head; node; node = node->next)
1058                         chain->last_offset += (FLAC__STREAM_METADATA_HEADER_LENGTH + node->data->length);
1059         }
1060
1061         return true;
1062 }
1063
1064 FLAC_API void FLAC__metadata_chain_merge_padding(FLAC__Metadata_Chain *chain)
1065 {
1066         FLAC__Metadata_Node *node;
1067
1068         FLAC__ASSERT(0 != chain);
1069
1070         for(node = chain->head; node; ) {
1071                 if(!chain_merge_adjacent_padding_(chain, node))
1072                         node = node->next;
1073         }
1074 }
1075
1076 FLAC_API void FLAC__metadata_chain_sort_padding(FLAC__Metadata_Chain *chain)
1077 {
1078         FLAC__Metadata_Node *node, *save;
1079         unsigned i;
1080
1081         FLAC__ASSERT(0 != chain);
1082
1083         /*
1084          * Don't try and be too smart... this simple algo is good enough for
1085          * the small number of nodes that we deal with.
1086          */
1087         for(i = 0, node = chain->head; i < chain->nodes; i++) {
1088                 if(node->data->type == FLAC__METADATA_TYPE_PADDING) {
1089                         save = node->next;
1090                         chain_remove_node_(chain, node);
1091                         chain_append_node_(chain, node);
1092                         node = save;
1093                 }
1094                 else {
1095                         node = node->next;
1096                 }
1097         }
1098
1099         FLAC__metadata_chain_merge_padding(chain);
1100 }
1101
1102
1103 FLAC_API FLAC__Metadata_Iterator *FLAC__metadata_iterator_new()
1104 {
1105         FLAC__Metadata_Iterator *iterator = (FLAC__Metadata_Iterator*)calloc(1, sizeof(FLAC__Metadata_Iterator));
1106
1107         /* calloc() implies:
1108                 iterator->current = 0;
1109                 iterator->chain = 0;
1110         */
1111
1112         return iterator;
1113 }
1114
1115 FLAC_API void FLAC__metadata_iterator_delete(FLAC__Metadata_Iterator *iterator)
1116 {
1117         FLAC__ASSERT(0 != iterator);
1118
1119         free(iterator);
1120 }
1121
1122 FLAC_API void FLAC__metadata_iterator_init(FLAC__Metadata_Iterator *iterator, FLAC__Metadata_Chain *chain)
1123 {
1124         FLAC__ASSERT(0 != iterator);
1125         FLAC__ASSERT(0 != chain);
1126         FLAC__ASSERT(0 != chain->head);
1127
1128         iterator->chain = chain;
1129         iterator->current = chain->head;
1130 }
1131
1132 FLAC_API FLAC__bool FLAC__metadata_iterator_next(FLAC__Metadata_Iterator *iterator)
1133 {
1134         FLAC__ASSERT(0 != iterator);
1135
1136         if(0 == iterator->current || 0 == iterator->current->next)
1137                 return false;
1138
1139         iterator->current = iterator->current->next;
1140         return true;
1141 }
1142
1143 FLAC_API FLAC__bool FLAC__metadata_iterator_prev(FLAC__Metadata_Iterator *iterator)
1144 {
1145         FLAC__ASSERT(0 != iterator);
1146
1147         if(0 == iterator->current || 0 == iterator->current->prev)
1148                 return false;
1149
1150         iterator->current = iterator->current->prev;
1151         return true;
1152 }
1153
1154 FLAC_API FLAC__MetadataType FLAC__metadata_iterator_get_block_type(const FLAC__Metadata_Iterator *iterator)
1155 {
1156         FLAC__ASSERT(0 != iterator);
1157         FLAC__ASSERT(0 != iterator->current);
1158         FLAC__ASSERT(0 != iterator->current->data);
1159
1160         return iterator->current->data->type;
1161 }
1162
1163 FLAC_API FLAC__StreamMetadata *FLAC__metadata_iterator_get_block(FLAC__Metadata_Iterator *iterator)
1164 {
1165         FLAC__ASSERT(0 != iterator);
1166         FLAC__ASSERT(0 != iterator->current);
1167
1168         return iterator->current->data;
1169 }
1170
1171 FLAC_API FLAC__bool FLAC__metadata_iterator_set_block(FLAC__Metadata_Iterator *iterator, FLAC__StreamMetadata *block)
1172 {
1173         FLAC__ASSERT(0 != iterator);
1174         FLAC__ASSERT(0 != block);
1175         return FLAC__metadata_iterator_delete_block(iterator, false) && FLAC__metadata_iterator_insert_block_after(iterator, block);
1176 }
1177
1178 FLAC_API FLAC__bool FLAC__metadata_iterator_delete_block(FLAC__Metadata_Iterator *iterator, FLAC__bool replace_with_padding)
1179 {
1180         FLAC__Metadata_Node *save;
1181
1182         FLAC__ASSERT(0 != iterator);
1183         FLAC__ASSERT(0 != iterator->current);
1184
1185         if(0 == iterator->current->prev) {
1186                 FLAC__ASSERT(iterator->current->data->type == FLAC__METADATA_TYPE_STREAMINFO);
1187                 return false;
1188         }
1189
1190         save = iterator->current->prev;
1191
1192         if(replace_with_padding) {
1193                 FLAC__metadata_object_delete_data(iterator->current->data);
1194                 iterator->current->data->type = FLAC__METADATA_TYPE_PADDING;
1195         }
1196         else {
1197                 chain_delete_node_(iterator->chain, iterator->current);
1198         }
1199
1200         iterator->current = save;
1201         return true;
1202 }
1203
1204 FLAC_API FLAC__bool FLAC__metadata_iterator_insert_block_before(FLAC__Metadata_Iterator *iterator, FLAC__StreamMetadata *block)
1205 {
1206         FLAC__Metadata_Node *node;
1207
1208         FLAC__ASSERT(0 != iterator);
1209         FLAC__ASSERT(0 != iterator->current);
1210         FLAC__ASSERT(0 != block);
1211
1212         if(block->type == FLAC__METADATA_TYPE_STREAMINFO)
1213                 return false;
1214
1215         if(0 == iterator->current->prev) {
1216                 FLAC__ASSERT(iterator->current->data->type == FLAC__METADATA_TYPE_STREAMINFO);
1217                 return false;
1218         }
1219
1220         if(0 == (node = node_new_()))
1221                 return false;
1222
1223         node->data = block;
1224         iterator_insert_node_(iterator, node);
1225         iterator->current = node;
1226         return true;
1227 }
1228
1229 FLAC_API FLAC__bool FLAC__metadata_iterator_insert_block_after(FLAC__Metadata_Iterator *iterator, FLAC__StreamMetadata *block)
1230 {
1231         FLAC__Metadata_Node *node;
1232
1233         FLAC__ASSERT(0 != iterator);
1234         FLAC__ASSERT(0 != iterator->current);
1235         FLAC__ASSERT(0 != block);
1236
1237         if(block->type == FLAC__METADATA_TYPE_STREAMINFO)
1238                 return false;
1239
1240         if(0 == (node = node_new_()))
1241                 return false;
1242
1243         node->data = block;
1244         iterator_insert_node_after_(iterator, node);
1245         iterator->current = node;
1246         return true;
1247 }
1248
1249
1250 /****************************************************************************
1251  *
1252  * Local function definitions
1253  *
1254  ***************************************************************************/
1255
1256 void pack_uint32_(FLAC__uint32 val, FLAC__byte *b, unsigned bytes)
1257 {
1258         unsigned i;
1259
1260         b += bytes;
1261
1262         for(i = 0; i < bytes; i++) {
1263                 *(--b) = (FLAC__byte)(val & 0xff);
1264                 val >>= 8;
1265         }
1266 }
1267
1268 void pack_uint32_little_endian_(FLAC__uint32 val, FLAC__byte *b, unsigned bytes)
1269 {
1270         unsigned i;
1271
1272         for(i = 0; i < bytes; i++) {
1273                 *(b++) = (FLAC__byte)(val & 0xff);
1274                 val >>= 8;
1275         }
1276 }
1277
1278 void pack_uint64_(FLAC__uint64 val, FLAC__byte *b, unsigned bytes)
1279 {
1280         unsigned i;
1281
1282         b += bytes;
1283
1284         for(i = 0; i < bytes; i++) {
1285                 *(--b) = (FLAC__byte)(val & 0xff);
1286                 val >>= 8;
1287         }
1288 }
1289
1290 FLAC__uint32 unpack_uint32_(FLAC__byte *b, unsigned bytes)
1291 {
1292         FLAC__uint32 ret = 0;
1293         unsigned i;
1294
1295         for(i = 0; i < bytes; i++)
1296                 ret = (ret << 8) | (FLAC__uint32)(*b++);
1297
1298         return ret;
1299 }
1300
1301 FLAC__uint32 unpack_uint32_little_endian_(FLAC__byte *b, unsigned bytes)
1302 {
1303         FLAC__uint32 ret = 0;
1304         unsigned i;
1305
1306         b += bytes;
1307
1308         for(i = 0; i < bytes; i++)
1309                 ret = (ret << 8) | (FLAC__uint32)(*--b);
1310
1311         return ret;
1312 }
1313
1314 FLAC__uint64 unpack_uint64_(FLAC__byte *b, unsigned bytes)
1315 {
1316         FLAC__uint64 ret = 0;
1317         unsigned i;
1318
1319         for(i = 0; i < bytes; i++)
1320                 ret = (ret << 8) | (FLAC__uint64)(*b++);
1321
1322         return ret;
1323 }
1324
1325 FLAC__bool read_metadata_block_header_(FLAC__Metadata_SimpleIterator *iterator)
1326 {
1327         FLAC__byte raw_header[FLAC__STREAM_METADATA_HEADER_LENGTH];
1328
1329         FLAC__ASSERT(0 != iterator);
1330         FLAC__ASSERT(0 != iterator->file);
1331
1332         if(fread(raw_header, 1, FLAC__STREAM_METADATA_HEADER_LENGTH, iterator->file) != FLAC__STREAM_METADATA_HEADER_LENGTH) {
1333                 iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1334                 return false;
1335         }
1336
1337         iterator->is_last = raw_header[0] & 0x80? true : false;
1338         iterator->type = (FLAC__MetadataType)(raw_header[0] & 0x7f);
1339         iterator->length = unpack_uint32_(raw_header + 1, 3);
1340
1341         /* do some checking */
1342         if(iterator->type >= FLAC__METADATA_TYPE_UNDEFINED) {
1343                 iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_BAD_METADATA;
1344                 return false;
1345         }
1346
1347         return true;
1348 }
1349
1350 FLAC__bool read_metadata_block_data_(FLAC__Metadata_SimpleIterator *iterator, FLAC__StreamMetadata *block)
1351 {
1352         FLAC__ASSERT(0 != iterator);
1353         FLAC__ASSERT(0 != iterator->file);
1354
1355         switch(block->type) {
1356                 case FLAC__METADATA_TYPE_STREAMINFO:
1357                         iterator->status = read_metadata_block_data_streaminfo_(iterator->file, &block->data.stream_info);
1358                         break;
1359                 case FLAC__METADATA_TYPE_PADDING:
1360                         iterator->status = read_metadata_block_data_padding_(iterator->file, &block->data.padding, block->length);
1361                         break;
1362                 case FLAC__METADATA_TYPE_APPLICATION:
1363                         iterator->status = read_metadata_block_data_application_(iterator->file, &block->data.application, block->length);
1364                         break;
1365                 case FLAC__METADATA_TYPE_SEEKTABLE:
1366                         iterator->status = read_metadata_block_data_seektable_(iterator->file, &block->data.seek_table, block->length);
1367                         break;
1368                 case FLAC__METADATA_TYPE_VORBIS_COMMENT:
1369                         iterator->status = read_metadata_block_data_vorbis_comment_(iterator->file, &block->data.vorbis_comment);
1370                         break;
1371                 case FLAC__METADATA_TYPE_CUESHEET:
1372                         iterator->status = read_metadata_block_data_cuesheet_(iterator->file, &block->data.cue_sheet);
1373                         break;
1374                 default:
1375                         FLAC__ASSERT(0);
1376                         iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_INTERNAL_ERROR;
1377         }
1378
1379         return (iterator->status == FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK);
1380 }
1381
1382 FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_streaminfo_(FILE *file, FLAC__StreamMetadata_StreamInfo *block)
1383 {
1384         FLAC__byte buffer[FLAC__STREAM_METADATA_STREAMINFO_LENGTH], *b;
1385
1386         FLAC__ASSERT(0 != file);
1387
1388         if(fread(buffer, 1, FLAC__STREAM_METADATA_STREAMINFO_LENGTH, file) != FLAC__STREAM_METADATA_STREAMINFO_LENGTH)
1389                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1390
1391         b = buffer;
1392
1393         /* @@@ we are using hardcoded numbers for simplicity but we should
1394          * probably eventually write a bit-level unpacker and use the
1395          * _STREAMINFO_ constants.
1396          */
1397         block->min_blocksize = unpack_uint32_(b, 2); b += 2;
1398         block->max_blocksize = unpack_uint32_(b, 2); b += 2;
1399         block->min_framesize = unpack_uint32_(b, 3); b += 3;
1400         block->max_framesize = unpack_uint32_(b, 3); b += 3;
1401         block->sample_rate = (unpack_uint32_(b, 2) << 4) | ((unsigned)(b[2] & 0xf0) >> 4);
1402         block->channels = (unsigned)((b[2] & 0x0e) >> 1) + 1;
1403         block->bits_per_sample = ((((unsigned)(b[2] & 0x01)) << 4) | (((unsigned)(b[3] & 0xf0)) >> 4)) + 1;
1404         block->total_samples = (((FLAC__uint64)(b[3] & 0x0f)) << 32) | unpack_uint64_(b+4, 4);
1405         memcpy(block->md5sum, b+8, 16);
1406
1407         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK;
1408 }
1409
1410
1411 FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_padding_(FILE *file, FLAC__StreamMetadata_Padding *block, unsigned block_length)
1412 {
1413         FLAC__ASSERT(0 != file);
1414
1415         (void)block; /* nothing to do; we don't care about reading the padding bytes */
1416
1417         if(0 != fseek(file, block_length, SEEK_CUR))
1418                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_SEEK_ERROR;
1419
1420         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK;
1421 }
1422
1423 FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_application_(FILE *file, FLAC__StreamMetadata_Application *block, unsigned block_length)
1424 {
1425         const unsigned id_bytes = FLAC__STREAM_METADATA_APPLICATION_ID_LEN / 8;
1426
1427         FLAC__ASSERT(0 != file);
1428
1429         if(fread(block->id, 1, id_bytes, file) != id_bytes)
1430                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1431
1432         block_length -= id_bytes;
1433
1434         if(block_length == 0) {
1435                 block->data = 0;
1436         }
1437         else {
1438                 if(0 == (block->data = (FLAC__byte*)malloc(block_length)))
1439                         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_MEMORY_ALLOCATION_ERROR;
1440
1441                 if(fread(block->data, 1, block_length, file) != block_length)
1442                         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1443         }
1444
1445         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK;
1446 }
1447
1448 FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_seektable_(FILE *file, FLAC__StreamMetadata_SeekTable *block, unsigned block_length)
1449 {
1450         unsigned i;
1451         FLAC__byte buffer[FLAC__STREAM_METADATA_SEEKPOINT_LENGTH];
1452
1453         FLAC__ASSERT(0 != file);
1454         FLAC__ASSERT(block_length % FLAC__STREAM_METADATA_SEEKPOINT_LENGTH == 0);
1455
1456         block->num_points = block_length / FLAC__STREAM_METADATA_SEEKPOINT_LENGTH;
1457
1458         if(block->num_points == 0)
1459                 block->points = 0;
1460         else if(0 == (block->points = (FLAC__StreamMetadata_SeekPoint*)malloc(block->num_points * sizeof(FLAC__StreamMetadata_SeekPoint))))
1461                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_MEMORY_ALLOCATION_ERROR;
1462
1463         for(i = 0; i < block->num_points; i++) {
1464                 if(fread(buffer, 1, FLAC__STREAM_METADATA_SEEKPOINT_LENGTH, file) != FLAC__STREAM_METADATA_SEEKPOINT_LENGTH)
1465                         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1466                 /*@@@ some MAGIC NUMBERs here */
1467                 block->points[i].sample_number = unpack_uint64_(buffer, 8);
1468                 block->points[i].stream_offset = unpack_uint64_(buffer+8, 8);
1469                 block->points[i].frame_samples = unpack_uint32_(buffer+16, 2);
1470         }
1471
1472         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK;
1473 }
1474
1475 FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_vorbis_comment_entry_(FILE *file, FLAC__StreamMetadata_VorbisComment_Entry *entry)
1476 {
1477         const unsigned entry_length_len = FLAC__STREAM_METADATA_VORBIS_COMMENT_ENTRY_LENGTH_LEN / 8;
1478         FLAC__byte buffer[4]; /* magic number is asserted below */
1479
1480         FLAC__ASSERT(FLAC__STREAM_METADATA_VORBIS_COMMENT_ENTRY_LENGTH_LEN / 8 == 4);
1481         FLAC__ASSERT(0 != file);
1482
1483         if(fread(buffer, 1, entry_length_len, file) != entry_length_len)
1484                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1485         entry->length = unpack_uint32_little_endian_(buffer, entry_length_len);
1486
1487         if(0 != entry->entry)
1488                 free(entry->entry);
1489
1490         if(entry->length == 0) {
1491                 entry->entry = 0;
1492         }
1493         else {
1494                 if(0 == (entry->entry = (FLAC__byte*)malloc(entry->length)))
1495                         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_MEMORY_ALLOCATION_ERROR;
1496
1497                 if(fread(entry->entry, 1, entry->length, file) != entry->length)
1498                         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1499         }
1500
1501         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK;
1502 }
1503
1504 FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_vorbis_comment_(FILE *file, FLAC__StreamMetadata_VorbisComment *block)
1505 {
1506         unsigned i;
1507         FLAC__Metadata_SimpleIteratorStatus status;
1508         const unsigned num_comments_len = FLAC__STREAM_METADATA_VORBIS_COMMENT_NUM_COMMENTS_LEN / 8;
1509         FLAC__byte buffer[4]; /* magic number is asserted below */
1510
1511         FLAC__ASSERT(FLAC__STREAM_METADATA_VORBIS_COMMENT_NUM_COMMENTS_LEN / 8 == 4);
1512         FLAC__ASSERT(0 != file);
1513
1514         if(FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK != (status = read_metadata_block_data_vorbis_comment_entry_(file, &(block->vendor_string))))
1515                 return status;
1516
1517         if(fread(buffer, 1, num_comments_len, file) != num_comments_len)
1518                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1519         block->num_comments = unpack_uint32_little_endian_(buffer, num_comments_len);
1520
1521         if(block->num_comments == 0) {
1522                 block->comments = 0;
1523         }
1524         else if(0 == (block->comments = (FLAC__StreamMetadata_VorbisComment_Entry*)calloc(block->num_comments, sizeof(FLAC__StreamMetadata_VorbisComment_Entry))))
1525                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_MEMORY_ALLOCATION_ERROR;
1526
1527         for(i = 0; i < block->num_comments; i++) {
1528                 if(FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK != (status = read_metadata_block_data_vorbis_comment_entry_(file, block->comments + i)))
1529                         return status;
1530         }
1531
1532         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK;
1533 }
1534
1535 FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_cuesheet_track_(FILE *file, FLAC__StreamMetadata_CueSheet_Track *track)
1536 {
1537         unsigned i, len;
1538         FLAC__byte buffer[32]; /* asserted below that this is big enough */
1539
1540         FLAC__ASSERT(sizeof(buffer) >= sizeof(FLAC__uint64));
1541         FLAC__ASSERT(sizeof(buffer) >= FLAC__STREAM_METADATA_CUESHEET_INDEX_RESERVED_LEN/8);
1542         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);
1543
1544         FLAC__ASSERT(0 != file);
1545
1546         FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_TRACK_OFFSET_LEN % 8 == 0);
1547         len = FLAC__STREAM_METADATA_CUESHEET_TRACK_OFFSET_LEN / 8;
1548         if(fread(buffer, 1, len, file) != len)
1549                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1550         track->offset = unpack_uint64_(buffer, len);
1551
1552         FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_TRACK_NUMBER_LEN % 8 == 0);
1553         len = FLAC__STREAM_METADATA_CUESHEET_TRACK_NUMBER_LEN / 8;
1554         if(fread(buffer, 1, len, file) != len)
1555                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1556         track->number = (FLAC__byte)unpack_uint32_(buffer, len);
1557
1558         FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_TRACK_ISRC_LEN % 8 == 0);
1559         len = FLAC__STREAM_METADATA_CUESHEET_TRACK_ISRC_LEN / 8;
1560         if(fread(track->isrc, 1, len, file) != len)
1561                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1562
1563         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);
1564         len = (FLAC__STREAM_METADATA_CUESHEET_TRACK_TYPE_LEN + FLAC__STREAM_METADATA_CUESHEET_TRACK_PRE_EMPHASIS_LEN + FLAC__STREAM_METADATA_CUESHEET_TRACK_RESERVED_LEN) / 8;
1565         if(fread(buffer, 1, len, file) != len)
1566                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1567         FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_TRACK_TYPE_LEN == 1);
1568         FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_TRACK_PRE_EMPHASIS_LEN == 1);
1569         track->type = buffer[0] >> 7;
1570         track->pre_emphasis = (buffer[0] >> 6) & 1;
1571
1572         FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_TRACK_NUM_INDICES_LEN % 8 == 0);
1573         len = FLAC__STREAM_METADATA_CUESHEET_TRACK_NUM_INDICES_LEN / 8;
1574         if(fread(buffer, 1, len, file) != len)
1575                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1576         track->num_indices = (FLAC__byte)unpack_uint32_(buffer, len);
1577
1578         if(track->num_indices == 0) {
1579                 track->indices = 0;
1580         }
1581         else if(0 == (track->indices = (FLAC__StreamMetadata_CueSheet_Index*)calloc(track->num_indices, sizeof(FLAC__StreamMetadata_CueSheet_Index))))
1582                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_MEMORY_ALLOCATION_ERROR;
1583
1584         for(i = 0; i < track->num_indices; i++) {
1585                 FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_INDEX_OFFSET_LEN % 8 == 0);
1586                 len = FLAC__STREAM_METADATA_CUESHEET_INDEX_OFFSET_LEN / 8;
1587                 if(fread(buffer, 1, len, file) != len)
1588                         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1589                 track->indices[i].offset = unpack_uint64_(buffer, len);
1590
1591                 FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_INDEX_NUMBER_LEN % 8 == 0);
1592                 len = FLAC__STREAM_METADATA_CUESHEET_INDEX_NUMBER_LEN / 8;
1593                 if(fread(buffer, 1, len, file) != len)
1594                         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1595                 track->indices[i].number = (FLAC__byte)unpack_uint32_(buffer, len);
1596
1597                 FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_INDEX_RESERVED_LEN % 8 == 0);
1598                 len = FLAC__STREAM_METADATA_CUESHEET_INDEX_RESERVED_LEN / 8;
1599                 if(fread(buffer, 1, len, file) != len)
1600                         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1601         }
1602
1603         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK;
1604 }
1605
1606 FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_cuesheet_(FILE *file, FLAC__StreamMetadata_CueSheet *block)
1607 {
1608         unsigned i, len;
1609         FLAC__Metadata_SimpleIteratorStatus status;
1610         FLAC__byte buffer[1024]; /* MSVC needs a constant expression so we put a magic number and assert */
1611
1612         FLAC__ASSERT(0 != file);
1613         FLAC__ASSERT((FLAC__STREAM_METADATA_CUESHEET_IS_CD_LEN + FLAC__STREAM_METADATA_CUESHEET_RESERVED_LEN)/8 <= sizeof(buffer));
1614         FLAC__ASSERT(sizeof(FLAC__uint64) <= sizeof(buffer));
1615
1616         FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_MEDIA_CATALOG_NUMBER_LEN % 8 == 0);
1617         len = FLAC__STREAM_METADATA_CUESHEET_MEDIA_CATALOG_NUMBER_LEN / 8;
1618         if(fread(block->media_catalog_number, 1, len, file) != len)
1619                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1620
1621         FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_LEAD_IN_LEN % 8 == 0);
1622         len = FLAC__STREAM_METADATA_CUESHEET_LEAD_IN_LEN / 8;
1623         if(fread(buffer, 1, len, file) != len)
1624                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1625         block->lead_in = unpack_uint64_(buffer, len);
1626
1627         FLAC__ASSERT((FLAC__STREAM_METADATA_CUESHEET_IS_CD_LEN + FLAC__STREAM_METADATA_CUESHEET_RESERVED_LEN) % 8 == 0);
1628         len = (FLAC__STREAM_METADATA_CUESHEET_IS_CD_LEN + FLAC__STREAM_METADATA_CUESHEET_RESERVED_LEN) / 8;
1629         if(fread(buffer, 1, len, file) != len)
1630                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1631         block->is_cd = buffer[0]&0x80? true : false;
1632
1633         FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_NUM_TRACKS_LEN % 8 == 0);
1634         len = FLAC__STREAM_METADATA_CUESHEET_NUM_TRACKS_LEN / 8;
1635         if(fread(buffer, 1, len, file) != len)
1636                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
1637         block->num_tracks = unpack_uint32_(buffer, len);
1638
1639         if(block->num_tracks == 0) {
1640                 block->tracks = 0;
1641         }
1642         else if(0 == (block->tracks = (FLAC__StreamMetadata_CueSheet_Track*)calloc(block->num_tracks, sizeof(FLAC__StreamMetadata_CueSheet_Track))))
1643                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_MEMORY_ALLOCATION_ERROR;
1644
1645         for(i = 0; i < block->num_tracks; i++) {
1646                 if(FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK != (status = read_metadata_block_data_cuesheet_track_(file, block->tracks + i)))
1647                         return status;
1648         }
1649
1650         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK;
1651 }
1652
1653 FLAC__bool write_metadata_block_header_(FILE *file, FLAC__Metadata_SimpleIteratorStatus *status, const FLAC__StreamMetadata *block)
1654 {
1655         FLAC__byte buffer[FLAC__STREAM_METADATA_HEADER_LENGTH];
1656
1657         FLAC__ASSERT(0 != file);
1658         FLAC__ASSERT(0 != status);
1659         FLAC__ASSERT(block->length < (1u << FLAC__STREAM_METADATA_LENGTH_LEN));
1660
1661         buffer[0] = (block->is_last? 0x80 : 0) | (FLAC__byte)block->type;
1662         pack_uint32_(block->length, buffer + 1, 3);
1663
1664         if(fwrite(buffer, 1, FLAC__STREAM_METADATA_HEADER_LENGTH, file) != FLAC__STREAM_METADATA_HEADER_LENGTH) {
1665                 *status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1666                 return false;
1667         }
1668
1669         return true;
1670 }
1671
1672 FLAC__bool write_metadata_block_data_(FILE *file, FLAC__Metadata_SimpleIteratorStatus *status, const FLAC__StreamMetadata *block)
1673 {
1674         FLAC__ASSERT(0 != file);
1675         FLAC__ASSERT(0 != status);
1676
1677         switch(block->type) {
1678                 case FLAC__METADATA_TYPE_STREAMINFO:
1679                         *status = write_metadata_block_data_streaminfo_(file, &block->data.stream_info);
1680                         break;
1681                 case FLAC__METADATA_TYPE_PADDING:
1682                         *status = write_metadata_block_data_padding_(file, &block->data.padding, block->length);
1683                         break;
1684                 case FLAC__METADATA_TYPE_APPLICATION:
1685                         *status = write_metadata_block_data_application_(file, &block->data.application, block->length);
1686                         break;
1687                 case FLAC__METADATA_TYPE_SEEKTABLE:
1688                         *status = write_metadata_block_data_seektable_(file, &block->data.seek_table);
1689                         break;
1690                 case FLAC__METADATA_TYPE_VORBIS_COMMENT:
1691                         *status = write_metadata_block_data_vorbis_comment_(file, &block->data.vorbis_comment);
1692                         break;
1693                 case FLAC__METADATA_TYPE_CUESHEET:
1694                         *status = write_metadata_block_data_cuesheet_(file, &block->data.cue_sheet);
1695                         break;
1696                 default:
1697                         FLAC__ASSERT(0);
1698                         *status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_INTERNAL_ERROR;
1699         }
1700         return (*status == FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK);
1701 }
1702
1703 FLAC__Metadata_SimpleIteratorStatus write_metadata_block_data_streaminfo_(FILE *file, const FLAC__StreamMetadata_StreamInfo *block)
1704 {
1705         FLAC__byte buffer[FLAC__STREAM_METADATA_STREAMINFO_LENGTH];
1706         const unsigned channels1 = block->channels - 1;
1707         const unsigned bps1 = block->bits_per_sample - 1;
1708
1709         FLAC__ASSERT(0 != file);
1710
1711         /* @@@ we are using hardcoded numbers for simplicity but we should
1712          * probably eventually write a bit-level packer and use the
1713          * _STREAMINFO_ constants.
1714          */
1715         pack_uint32_(block->min_blocksize, buffer, 2);
1716         pack_uint32_(block->max_blocksize, buffer+2, 2);
1717         pack_uint32_(block->min_framesize, buffer+4, 3);
1718         pack_uint32_(block->max_framesize, buffer+7, 3);
1719         buffer[10] = (block->sample_rate >> 12) & 0xff;
1720         buffer[11] = (block->sample_rate >> 4) & 0xff;
1721         buffer[12] = ((block->sample_rate & 0x0f) << 4) | (channels1 << 1) | (bps1 >> 4);
1722         buffer[13] = (FLAC__byte)(((bps1 & 0x0f) << 4) | ((block->total_samples >> 32) & 0x0f));
1723         pack_uint32_((FLAC__uint32)block->total_samples, buffer+14, 4);
1724         memcpy(buffer+18, block->md5sum, 16);
1725
1726         if(fwrite(buffer, 1, FLAC__STREAM_METADATA_STREAMINFO_LENGTH, file) != FLAC__STREAM_METADATA_STREAMINFO_LENGTH)
1727                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1728
1729         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK;
1730 }
1731
1732 FLAC__Metadata_SimpleIteratorStatus write_metadata_block_data_padding_(FILE *file, const FLAC__StreamMetadata_Padding *block, unsigned block_length)
1733 {
1734         unsigned i, n = block_length;
1735         FLAC__byte buffer[1024];
1736
1737         FLAC__ASSERT(0 != file);
1738
1739         (void)block;
1740
1741         memset(buffer, 0, 1024);
1742
1743         for(i = 0; i < n/1024; i++)
1744                 if(fwrite(buffer, 1, 1024, file) != 1024)
1745                         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1746
1747         n %= 1024;
1748
1749         if(fwrite(buffer, 1, n, file) != n)
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_application_(FILE *file, const FLAC__StreamMetadata_Application *block, unsigned block_length)
1756 {
1757         const unsigned id_bytes = FLAC__STREAM_METADATA_APPLICATION_ID_LEN / 8;
1758
1759         FLAC__ASSERT(0 != file);
1760
1761         if(fwrite(block->id, 1, id_bytes, file) != id_bytes)
1762                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1763
1764         block_length -= id_bytes;
1765
1766         if(fwrite(block->data, 1, block_length, file) != block_length)
1767                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1768
1769         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK;
1770 }
1771
1772 FLAC__Metadata_SimpleIteratorStatus write_metadata_block_data_seektable_(FILE *file, const FLAC__StreamMetadata_SeekTable *block)
1773 {
1774         unsigned i;
1775         FLAC__byte buffer[FLAC__STREAM_METADATA_SEEKPOINT_LENGTH];
1776
1777         FLAC__ASSERT(0 != file);
1778
1779         for(i = 0; i < block->num_points; i++) {
1780                 /*@@@ some MAGIC NUMBERs here */
1781                 pack_uint64_(block->points[i].sample_number, buffer, 8);
1782                 pack_uint64_(block->points[i].stream_offset, buffer+8, 8);
1783                 pack_uint32_(block->points[i].frame_samples, buffer+16, 2);
1784                 if(fwrite(buffer, 1, FLAC__STREAM_METADATA_SEEKPOINT_LENGTH, file) != FLAC__STREAM_METADATA_SEEKPOINT_LENGTH)
1785                         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1786         }
1787
1788         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK;
1789 }
1790
1791 FLAC__Metadata_SimpleIteratorStatus write_metadata_block_data_vorbis_comment_(FILE *file, const FLAC__StreamMetadata_VorbisComment *block)
1792 {
1793         unsigned i;
1794         const unsigned entry_length_len = FLAC__STREAM_METADATA_VORBIS_COMMENT_ENTRY_LENGTH_LEN / 8;
1795         const unsigned num_comments_len = FLAC__STREAM_METADATA_VORBIS_COMMENT_NUM_COMMENTS_LEN / 8;
1796         FLAC__byte buffer[4]; /* magic number is asserted below */
1797
1798         FLAC__ASSERT(max(FLAC__STREAM_METADATA_VORBIS_COMMENT_ENTRY_LENGTH_LEN, FLAC__STREAM_METADATA_VORBIS_COMMENT_NUM_COMMENTS_LEN) / 8 == 4);
1799         FLAC__ASSERT(0 != file);
1800
1801         pack_uint32_little_endian_(block->vendor_string.length, buffer, entry_length_len);
1802         if(fwrite(buffer, 1, entry_length_len, file) != entry_length_len)
1803                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1804         if(fwrite(block->vendor_string.entry, 1, block->vendor_string.length, file) != block->vendor_string.length)
1805                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1806
1807         pack_uint32_little_endian_(block->num_comments, buffer, num_comments_len);
1808         if(fwrite(buffer, 1, num_comments_len, file) != num_comments_len)
1809                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1810
1811         for(i = 0; i < block->num_comments; i++) {
1812                 pack_uint32_little_endian_(block->comments[i].length, buffer, entry_length_len);
1813                 if(fwrite(buffer, 1, entry_length_len, file) != entry_length_len)
1814                         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1815                 if(fwrite(block->comments[i].entry, 1, block->comments[i].length, file) != block->comments[i].length)
1816                         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1817         }
1818
1819         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK;
1820 }
1821
1822 FLAC__Metadata_SimpleIteratorStatus write_metadata_block_data_cuesheet_(FILE *file, const FLAC__StreamMetadata_CueSheet *block)
1823 {
1824         unsigned i, j, len;
1825         FLAC__byte buffer[1024]; /* asserted below that this is big enough */
1826
1827         FLAC__ASSERT(sizeof(buffer) >= sizeof(FLAC__uint64));
1828         FLAC__ASSERT(sizeof(buffer) >= FLAC__STREAM_METADATA_CUESHEET_RESERVED_LEN/8);
1829         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);
1830         FLAC__ASSERT(sizeof(buffer) >= FLAC__STREAM_METADATA_CUESHEET_INDEX_RESERVED_LEN/8);
1831
1832         FLAC__ASSERT(0 != file);
1833
1834         FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_MEDIA_CATALOG_NUMBER_LEN % 8 == 0);
1835         len = FLAC__STREAM_METADATA_CUESHEET_MEDIA_CATALOG_NUMBER_LEN / 8;
1836         if(fwrite(block->media_catalog_number, 1, len, file) != len)
1837                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1838
1839         FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_LEAD_IN_LEN % 8 == 0);
1840         len = FLAC__STREAM_METADATA_CUESHEET_LEAD_IN_LEN / 8;
1841         pack_uint64_(block->lead_in, buffer, len);
1842         if(fwrite(buffer, 1, len, file) != len)
1843                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1844
1845         FLAC__ASSERT((FLAC__STREAM_METADATA_CUESHEET_IS_CD_LEN + FLAC__STREAM_METADATA_CUESHEET_RESERVED_LEN) % 8 == 0);
1846         len = (FLAC__STREAM_METADATA_CUESHEET_IS_CD_LEN + FLAC__STREAM_METADATA_CUESHEET_RESERVED_LEN) / 8;
1847         memset(buffer, 0, len);
1848         if(block->is_cd)
1849                 buffer[0] |= 0x80;
1850         if(fwrite(buffer, 1, len, file) != len)
1851                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1852
1853         FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_NUM_TRACKS_LEN % 8 == 0);
1854         len = FLAC__STREAM_METADATA_CUESHEET_NUM_TRACKS_LEN / 8;
1855         pack_uint32_(block->num_tracks, buffer, len);
1856         if(fwrite(buffer, 1, len, file) != len)
1857                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1858
1859         for(i = 0; i < block->num_tracks; i++) {
1860                 FLAC__StreamMetadata_CueSheet_Track *track = block->tracks + i;
1861
1862                 FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_TRACK_OFFSET_LEN % 8 == 0);
1863                 len = FLAC__STREAM_METADATA_CUESHEET_TRACK_OFFSET_LEN / 8;
1864                 pack_uint64_(track->offset, buffer, len);
1865                 if(fwrite(buffer, 1, len, file) != len)
1866                         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1867
1868                 FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_TRACK_NUMBER_LEN % 8 == 0);
1869                 len = FLAC__STREAM_METADATA_CUESHEET_TRACK_NUMBER_LEN / 8;
1870                 pack_uint32_(track->number, buffer, len);
1871                 if(fwrite(buffer, 1, len, file) != len)
1872                         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1873
1874                 FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_TRACK_ISRC_LEN % 8 == 0);
1875                 len = FLAC__STREAM_METADATA_CUESHEET_TRACK_ISRC_LEN / 8;
1876                 if(fwrite(track->isrc, 1, len, file) != len)
1877                         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1878
1879                 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);
1880                 len = (FLAC__STREAM_METADATA_CUESHEET_TRACK_TYPE_LEN + FLAC__STREAM_METADATA_CUESHEET_TRACK_PRE_EMPHASIS_LEN + FLAC__STREAM_METADATA_CUESHEET_TRACK_RESERVED_LEN) / 8;
1881                 memset(buffer, 0, len);
1882                 buffer[0] = (track->type << 7) | (track->pre_emphasis << 6);
1883                 if(fwrite(buffer, 1, len, file) != len)
1884                         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1885
1886                 FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_TRACK_NUM_INDICES_LEN % 8 == 0);
1887                 len = FLAC__STREAM_METADATA_CUESHEET_TRACK_NUM_INDICES_LEN / 8;
1888                 pack_uint32_(track->num_indices, buffer, len);
1889                 if(fwrite(buffer, 1, len, file) != len)
1890                         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1891
1892                 for(j = 0; j < track->num_indices; j++) {
1893                         FLAC__StreamMetadata_CueSheet_Index *index = track->indices + j;
1894
1895                         FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_INDEX_OFFSET_LEN % 8 == 0);
1896                         len = FLAC__STREAM_METADATA_CUESHEET_INDEX_OFFSET_LEN / 8;
1897                         pack_uint64_(index->offset, buffer, len);
1898                         if(fwrite(buffer, 1, len, file) != len)
1899                                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1900
1901                         FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_INDEX_NUMBER_LEN % 8 == 0);
1902                         len = FLAC__STREAM_METADATA_CUESHEET_INDEX_NUMBER_LEN / 8;
1903                         pack_uint32_(index->number, buffer, len);
1904                         if(fwrite(buffer, 1, len, file) != len)
1905                                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1906
1907                         FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_INDEX_RESERVED_LEN % 8 == 0);
1908                         len = FLAC__STREAM_METADATA_CUESHEET_INDEX_RESERVED_LEN / 8;
1909                         memset(buffer, 0, len);
1910                         if(fwrite(buffer, 1, len, file) != len)
1911                                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
1912                 }
1913         }
1914
1915         return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK;
1916 }
1917
1918 FLAC__bool write_metadata_block_stationary_(FLAC__Metadata_SimpleIterator *iterator, const FLAC__StreamMetadata *block)
1919 {
1920         if(0 != fseek(iterator->file, iterator->offset[iterator->depth], SEEK_SET)) {
1921                 iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_SEEK_ERROR;
1922                 return false;
1923         }
1924
1925         if(!write_metadata_block_header_(iterator->file, &iterator->status, block))
1926                 return false;
1927
1928         if(!write_metadata_block_data_(iterator->file, &iterator->status, block))
1929                 return false;
1930
1931         if(0 != fseek(iterator->file, iterator->offset[iterator->depth], SEEK_SET)) {
1932                 iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_SEEK_ERROR;
1933                 return false;
1934         }
1935
1936         return read_metadata_block_header_(iterator);
1937 }
1938
1939 FLAC__bool write_metadata_block_stationary_with_padding_(FLAC__Metadata_SimpleIterator *iterator, FLAC__StreamMetadata *block, unsigned padding_length, FLAC__bool padding_is_last)
1940 {
1941         FLAC__StreamMetadata *padding;
1942
1943         if(0 != fseek(iterator->file, iterator->offset[iterator->depth], SEEK_SET)) {
1944                 iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_SEEK_ERROR;
1945                 return false;
1946         }
1947
1948         block->is_last = false;
1949
1950         if(!write_metadata_block_header_(iterator->file, &iterator->status, block))
1951                 return false;
1952
1953         if(!write_metadata_block_data_(iterator->file, &iterator->status, block))
1954                 return false;
1955
1956         if(0 == (padding = FLAC__metadata_object_new(FLAC__METADATA_TYPE_PADDING)))
1957                 return FLAC__METADATA_SIMPLE_ITERATOR_STATUS_MEMORY_ALLOCATION_ERROR;
1958
1959         padding->is_last = padding_is_last;
1960         padding->length = padding_length;
1961
1962         if(!write_metadata_block_header_(iterator->file, &iterator->status, padding)) {
1963                 FLAC__metadata_object_delete(padding);
1964                 return false;
1965         }
1966
1967         if(!write_metadata_block_data_(iterator->file, &iterator->status, padding)) {
1968                 FLAC__metadata_object_delete(padding);
1969                 return false;
1970         }
1971
1972         FLAC__metadata_object_delete(padding);
1973
1974         if(0 != fseek(iterator->file, iterator->offset[iterator->depth], SEEK_SET)) {
1975                 iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_SEEK_ERROR;
1976                 return false;
1977         }
1978
1979         return read_metadata_block_header_(iterator);
1980 }
1981
1982 FLAC__bool rewrite_whole_file_(FLAC__Metadata_SimpleIterator *iterator, FLAC__StreamMetadata *block, FLAC__bool append)
1983 {
1984         FILE *tempfile;
1985         char *tempfilename;
1986         int fixup_is_last_code = 0; /* 0 => no need to change any is_last flags */
1987         long fixup_is_last_flag_offset = -1;
1988
1989         FLAC__ASSERT(0 != block || append == false);
1990
1991         if(iterator->is_last) {
1992                 if(append) {
1993                         fixup_is_last_code = 1; /* 1 => clear the is_last flag at the following offset */
1994                         fixup_is_last_flag_offset = iterator->offset[iterator->depth];
1995                 }
1996                 else if(0 == block) {
1997                         simple_iterator_push_(iterator);
1998                         if(!FLAC__metadata_simple_iterator_prev(iterator)) {
1999                                 (void)simple_iterator_pop_(iterator);
2000                                 return false;
2001                         }
2002                         fixup_is_last_code = -1; /* -1 => set the is_last the flag at the following offset */
2003                         fixup_is_last_flag_offset = iterator->offset[iterator->depth];
2004                         if(!simple_iterator_pop_(iterator))
2005                                 return false;
2006                 }
2007         }
2008
2009         if(!simple_iterator_copy_file_prefix_(iterator, &tempfile, &tempfilename, append))
2010                 return false;
2011
2012         if(0 != block) {
2013                 if(!write_metadata_block_header_(tempfile, &iterator->status, block)) {
2014                         cleanup_tempfile_(&tempfile, &tempfilename);
2015                         return false;
2016                 }
2017
2018                 if(!write_metadata_block_data_(tempfile, &iterator->status, block)) {
2019                         cleanup_tempfile_(&tempfile, &tempfilename);
2020                         return false;
2021                 }
2022         }
2023
2024         if(!simple_iterator_copy_file_postfix_(iterator, &tempfile, &tempfilename, fixup_is_last_code, fixup_is_last_flag_offset, block==0))
2025                 return false;
2026
2027         if(append)
2028                 return FLAC__metadata_simple_iterator_next(iterator);
2029
2030         return true;
2031 }
2032
2033 FLAC__bool chain_rewrite_chain_(FLAC__Metadata_Chain *chain)
2034 {
2035         FILE *f;
2036         FLAC__Metadata_Node *node;
2037         FLAC__Metadata_SimpleIteratorStatus status;
2038
2039         FLAC__ASSERT(0 != chain);
2040         FLAC__ASSERT(0 != chain->filename);
2041         FLAC__ASSERT(0 != chain->head);
2042
2043         if(0 == (f = fopen(chain->filename, "r+b"))) {
2044                 chain->status = FLAC__METADATA_CHAIN_STATUS_ERROR_OPENING_FILE;
2045                 return false;
2046         }
2047         if(0 != fseek(f, chain->first_offset, SEEK_SET)) {
2048                 chain->status = FLAC__METADATA_CHAIN_STATUS_SEEK_ERROR;
2049                 return false;
2050         }
2051
2052         for(node = chain->head; node; node = node->next) {
2053                 if(!write_metadata_block_header_(f, &status, node->data)) {
2054                         chain->status = get_equivalent_status_(status);
2055                         return false;
2056                 }
2057                 if(!write_metadata_block_data_(f, &status, node->data)) {
2058                         chain->status = get_equivalent_status_(status);
2059                         return false;
2060                 }
2061         }
2062
2063         /*FLAC__ASSERT(fflush(), ftell() == chain->last_offset);*/
2064
2065         (void)fclose(f);
2066
2067         return true;
2068 }
2069
2070 FLAC__bool chain_rewrite_file_(FLAC__Metadata_Chain *chain, const char *tempfile_path_prefix)
2071 {
2072         FILE *f, *tempfile;
2073         char *tempfilename;
2074         FLAC__Metadata_SimpleIteratorStatus status;
2075         const FLAC__Metadata_Node *node;
2076
2077         FLAC__ASSERT(0 != chain);
2078         FLAC__ASSERT(0 != chain->filename);
2079         FLAC__ASSERT(0 != chain->head);
2080
2081         /* copy the file prefix (data up to first metadata block */
2082         if(0 == (f = fopen(chain->filename, "rb"))) {
2083                 chain->status = FLAC__METADATA_CHAIN_STATUS_ERROR_OPENING_FILE;
2084                 return false;
2085         }
2086         if(!open_tempfile_(chain->filename, tempfile_path_prefix, &tempfile, &tempfilename, &status)) {
2087                 chain->status = get_equivalent_status_(status);
2088                 cleanup_tempfile_(&tempfile, &tempfilename);
2089                 return false;
2090         }
2091         if(!copy_n_bytes_from_file_(f, tempfile, chain->first_offset, &status)) {
2092                 chain->status = get_equivalent_status_(status);
2093                 cleanup_tempfile_(&tempfile, &tempfilename);
2094                 return false;
2095         }
2096
2097         /* write the metadata */
2098         for(node = chain->head; node; node = node->next) {
2099                 if(!write_metadata_block_header_(tempfile, &status, node->data)) {
2100                         chain->status = get_equivalent_status_(status);
2101                         return false;
2102                 }
2103                 if(!write_metadata_block_data_(tempfile, &status, node->data)) {
2104                         chain->status = get_equivalent_status_(status);
2105                         return false;
2106                 }
2107         }
2108         /*FLAC__ASSERT(fflush(), ftell() == chain->last_offset);*/
2109
2110         /* copy the file postfix (everything after the metadata) */
2111         if(0 != fseek(f, chain->last_offset, SEEK_SET)) {
2112                 cleanup_tempfile_(&tempfile, &tempfilename);
2113                 chain->status = FLAC__METADATA_CHAIN_STATUS_SEEK_ERROR;
2114                 return false;
2115         }
2116         if(!copy_remaining_bytes_from_file_(f, tempfile, &status)) {
2117                 cleanup_tempfile_(&tempfile, &tempfilename);
2118                 chain->status = get_equivalent_status_(status);
2119                 return false;
2120         }
2121
2122         /* move the tempfile on top of the original */
2123         (void)fclose(f);
2124         if(!transport_tempfile_(chain->filename, &tempfile, &tempfilename, &status))
2125                 return false;
2126
2127         return true;
2128 }
2129
2130 void simple_iterator_push_(FLAC__Metadata_SimpleIterator *iterator)
2131 {
2132         FLAC__ASSERT(iterator->depth+1 < SIMPLE_ITERATOR_MAX_PUSH_DEPTH);
2133         iterator->offset[iterator->depth+1] = iterator->offset[iterator->depth];
2134         iterator->depth++;
2135 }
2136
2137 FLAC__bool simple_iterator_pop_(FLAC__Metadata_SimpleIterator *iterator)
2138 {
2139         FLAC__ASSERT(iterator->depth > 0);
2140         iterator->depth--;
2141         if(0 != fseek(iterator->file, iterator->offset[iterator->depth], SEEK_SET)) {
2142                 iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_SEEK_ERROR;
2143                 return false;
2144         }
2145
2146         return read_metadata_block_header_(iterator);
2147 }
2148
2149 unsigned seek_to_first_metadata_block_(FILE *f)
2150 {
2151         FLAC__byte buffer[4];
2152         size_t n;
2153         unsigned i;
2154
2155         FLAC__ASSERT(0 != f);
2156         FLAC__ASSERT(FLAC__STREAM_SYNC_LENGTH == 4);
2157
2158         /* skip any id3v2 tag */
2159 #if !defined _MSC_VER && !defined __MINGW32__
2160 /*@@@ don't know how to resolve errno without using LIBC.LIB; must use MSVCRT.LIB only for plugins */
2161         errno = 0;
2162 #endif
2163         n = fread(buffer, 1, 4, f);
2164 #if !defined _MSC_VER && !defined __MINGW32__
2165 /*@@@ don't know how to resolve errno without using LIBC.LIB; must use MSVCRT.LIB only for plugins */
2166         if(errno)
2167                 return 1;
2168         else
2169 #endif
2170         if(n != 4)
2171                 return 2;
2172         else if(0 == memcmp(buffer, "ID3", 3)) {
2173                 unsigned tag_length = 0;
2174
2175                 /* skip to the tag length */
2176                 if(fseek(f, 2, SEEK_CUR) < 0)
2177                         return 1;
2178
2179                 /* read the length */
2180                 for(i = 0; i < 4; i++) {
2181                         if(fread(buffer, 1, 1, f) < 1 || buffer[0] & 0x80)
2182                                 return 1;
2183                         tag_length <<= 7;
2184                         tag_length |= (buffer[0] & 0x7f);
2185                 }
2186
2187                 /* skip the rest of the tag */
2188                 if(fseek(f, tag_length, SEEK_CUR) < 0)
2189                         return 1;
2190
2191                 /* read the stream sync code */
2192 #if !defined _MSC_VER && !defined __MINGW32__
2193 /*@@@ don't know how to resolve errno without using LIBC.LIB; must use MSVCRT.LIB only for plugins */
2194                 errno = 0;
2195 #endif
2196                 n = fread(buffer, 1, 4, f);
2197 #if !defined _MSC_VER && !defined __MINGW32__
2198 /*@@@ don't know how to resolve errno without using LIBC.LIB; must use MSVCRT.LIB only for plugins */
2199                 if(errno)
2200                         return 1;
2201                 else
2202 #endif
2203                 if(n != 4)
2204                         return 2;
2205         }
2206
2207         /* check for the fLaC signature */
2208         if(0 == memcmp(FLAC__STREAM_SYNC_STRING, buffer, FLAC__STREAM_SYNC_LENGTH))
2209                 return 0;
2210         else
2211                 return 2;
2212 }
2213
2214 FLAC__bool simple_iterator_copy_file_prefix_(FLAC__Metadata_SimpleIterator *iterator, FILE **tempfile, char **tempfilename, FLAC__bool append)
2215 {
2216         const long offset_end = append? iterator->offset[iterator->depth] + (long)FLAC__STREAM_METADATA_HEADER_LENGTH + (long)iterator->length : iterator->offset[iterator->depth];
2217
2218         if(0 != fseek(iterator->file, 0, SEEK_SET)) {
2219                 iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_SEEK_ERROR;
2220                 return false;
2221         }
2222         if(!open_tempfile_(iterator->filename, iterator->tempfile_path_prefix, tempfile, tempfilename, &iterator->status)) {
2223                 cleanup_tempfile_(tempfile, tempfilename);
2224                 return false;
2225         }
2226         if(!copy_n_bytes_from_file_(iterator->file, *tempfile, offset_end, &iterator->status)) {
2227                 cleanup_tempfile_(tempfile, tempfilename);
2228                 return false;
2229         }
2230
2231         return true;
2232 }
2233
2234 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)
2235 {
2236         long save_offset = iterator->offset[iterator->depth]; /*@@@ 2G limit */
2237         FLAC__ASSERT(0 != *tempfile);
2238
2239         if(0 != fseek(iterator->file, save_offset + FLAC__STREAM_METADATA_HEADER_LENGTH + iterator->length, SEEK_SET)) {
2240                 cleanup_tempfile_(tempfile, tempfilename);
2241                 iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_SEEK_ERROR;
2242                 return false;
2243         }
2244         if(!copy_remaining_bytes_from_file_(iterator->file, *tempfile, &iterator->status)) {
2245                 cleanup_tempfile_(tempfile, tempfilename);
2246                 return false;
2247         }
2248
2249         if(fixup_is_last_code != 0) {
2250                 /*
2251                  * if code == 1, it means a block was appended to the end so
2252                  *   we have to clear the is_last flag of the previous block
2253                  * if code == -1, it means the last block was deleted so
2254                  *   we have to set the is_last flag of the previous block
2255                  */
2256                 /*@@@ MAGIC NUMBERs here; we know the is_last flag is the high bit of the byte at this location */
2257                 FLAC__byte x;
2258                 if(0 != fseek(*tempfile, fixup_is_last_flag_offset, SEEK_SET)) {
2259                         cleanup_tempfile_(tempfile, tempfilename);
2260                         iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_SEEK_ERROR;
2261                         return false;
2262                 }
2263                 if(fread(&x, 1, 1, *tempfile) != 1) {
2264                         cleanup_tempfile_(tempfile, tempfilename);
2265                         iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
2266                         return false;
2267                 }
2268                 if(fixup_is_last_code > 0) {
2269                         FLAC__ASSERT(x & 0x80);
2270                         x &= 0x7f;
2271                 }
2272                 else {
2273                         FLAC__ASSERT(!(x & 0x80));
2274                         x |= 0x80;
2275                 }
2276                 if(0 != fseek(*tempfile, fixup_is_last_flag_offset, SEEK_SET)) {
2277                         cleanup_tempfile_(tempfile, tempfilename);
2278                         iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_SEEK_ERROR;
2279                         return false;
2280                 }
2281                 if(fwrite(&x, 1, 1, *tempfile) != 1) {
2282                         cleanup_tempfile_(tempfile, tempfilename);
2283                         iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
2284                         return false;
2285                 }
2286         }
2287
2288         (void)fclose(iterator->file);
2289
2290         if(!transport_tempfile_(iterator->filename, tempfile, tempfilename, &iterator->status))
2291                 return false;
2292
2293         if(iterator->has_stats)
2294                 set_file_stats_(iterator->filename, &iterator->stats);
2295
2296         if(!simple_iterator_prime_input_(iterator, !iterator->is_writable))
2297                 return false;
2298         if(backup) {
2299                 while(iterator->offset[iterator->depth] + (long)FLAC__STREAM_METADATA_HEADER_LENGTH + (long)iterator->length < save_offset)
2300                         if(!FLAC__metadata_simple_iterator_next(iterator))
2301                                 return false;
2302                 return true;
2303         }
2304         else {
2305                 /* move the iterator to it's original block faster by faking a push, then doing a pop_ */
2306                 FLAC__ASSERT(iterator->depth == 0);
2307                 iterator->offset[0] = save_offset;
2308                 iterator->depth++;
2309                 return simple_iterator_pop_(iterator);
2310         }
2311 }
2312
2313 FLAC__bool copy_n_bytes_from_file_(FILE *file, FILE *tempfile, unsigned bytes/*@@@ 4G limit*/, FLAC__Metadata_SimpleIteratorStatus *status)
2314 {
2315         FLAC__byte buffer[8192];
2316         unsigned n;
2317
2318         while(bytes > 0) {
2319                 n = min(sizeof(buffer), bytes);
2320                 if(fread(buffer, 1, n, file) != n) {
2321                         *status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
2322                         return false;
2323                 }
2324                 if(fwrite(buffer, 1, n, tempfile) != n) {
2325                         *status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
2326                         return false;
2327                 }
2328                 bytes -= n;
2329         }
2330
2331         return true;
2332 }
2333
2334 FLAC__bool copy_remaining_bytes_from_file_(FILE *file, FILE *tempfile, FLAC__Metadata_SimpleIteratorStatus *status)
2335 {
2336         FLAC__byte buffer[8192];
2337         size_t n;
2338
2339         while(!feof(file)) {
2340                 n = fread(buffer, 1, sizeof(buffer), file);
2341                 if(n == 0 && !feof(file)) {
2342                         *status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
2343                         return false;
2344                 }
2345                 if(n > 0 && fwrite(buffer, 1, n, tempfile) != n) {
2346                         *status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR;
2347                         return false;
2348                 }
2349         }
2350
2351         return true;
2352 }
2353
2354 FLAC__bool open_tempfile_(const char *filename, const char *tempfile_path_prefix, FILE **tempfile, char **tempfilename, FLAC__Metadata_SimpleIteratorStatus *status)
2355 {
2356         static const char *tempfile_suffix = ".metadata_edit";
2357         if(0 == tempfile_path_prefix) {
2358                 if(0 == (*tempfilename = (char*)malloc(strlen(filename) + strlen(tempfile_suffix) + 1))) {
2359                         *status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_MEMORY_ALLOCATION_ERROR;
2360                         return false;
2361                 }
2362                 strcpy(*tempfilename, filename);
2363                 strcat(*tempfilename, tempfile_suffix);
2364         }
2365         else {
2366                 const char *p = strrchr(filename, '/');
2367                 if(0 == p)
2368                         p = filename;
2369                 else
2370                         p++;
2371
2372                 if(0 == (*tempfilename = (char*)malloc(strlen(tempfile_path_prefix) + 1 + strlen(p) + strlen(tempfile_suffix) + 1))) {
2373                         *status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_MEMORY_ALLOCATION_ERROR;
2374                         return false;
2375                 }
2376                 strcpy(*tempfilename, tempfile_path_prefix);
2377                 strcat(*tempfilename, "/");
2378                 strcat(*tempfilename, p);
2379                 strcat(*tempfilename, tempfile_suffix);
2380         }
2381
2382         if(0 == (*tempfile = fopen(*tempfilename, "w+b"))) {
2383                 *status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_ERROR_OPENING_FILE;
2384                 return false;
2385         }
2386
2387         return true;
2388 }
2389
2390 FLAC__bool transport_tempfile_(const char *filename, FILE **tempfile, char **tempfilename, FLAC__Metadata_SimpleIteratorStatus *status)
2391 {
2392         FLAC__ASSERT(0 != filename);
2393         FLAC__ASSERT(0 != tempfile);
2394         FLAC__ASSERT(0 != *tempfile);
2395         FLAC__ASSERT(0 != tempfilename);
2396         FLAC__ASSERT(0 != *tempfilename);
2397         FLAC__ASSERT(0 != status);
2398
2399         (void)fclose(*tempfile);
2400         *tempfile = 0;
2401
2402 #if defined _MSC_VER || defined __MINGW32__
2403         if(unlink(filename) < 0) {
2404                 cleanup_tempfile_(tempfile, tempfilename);
2405                 *status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_UNLINK_ERROR;
2406                 return false;
2407         }
2408 #endif
2409
2410         /*@@@ to fully support the tempfile_path_prefix we need to update this piece to actually copy across filesystems instead of just rename(): */
2411         if(0 != rename(*tempfilename, filename)) {
2412                 cleanup_tempfile_(tempfile, tempfilename);
2413                 *status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_RENAME_ERROR;
2414                 return false;
2415         }
2416
2417         cleanup_tempfile_(tempfile, tempfilename);
2418
2419         return true;
2420 }
2421
2422 void cleanup_tempfile_(FILE **tempfile, char **tempfilename)
2423 {
2424         if(0 != *tempfile) {
2425                 (void)fclose(*tempfile);
2426                 *tempfile = 0;
2427         }
2428
2429         if(0 != *tempfilename) {
2430                 (void)unlink(*tempfilename);
2431                 free(*tempfilename);
2432                 *tempfilename = 0;
2433         }
2434 }
2435
2436 FLAC__bool get_file_stats_(const char *filename, struct stat *stats)
2437 {
2438         FLAC__ASSERT(0 != filename);
2439         FLAC__ASSERT(0 != stats);
2440         return (0 == stat(filename, stats));
2441 }
2442
2443 void set_file_stats_(const char *filename, struct stat *stats)
2444 {
2445         struct utimbuf srctime;
2446
2447         FLAC__ASSERT(0 != filename);
2448         FLAC__ASSERT(0 != stats);
2449
2450         srctime.actime = stats->st_atime;
2451         srctime.modtime = stats->st_mtime;
2452         (void)chmod(filename, stats->st_mode);
2453         (void)utime(filename, &srctime);
2454 #if !defined _MSC_VER && !defined __MINGW32__
2455         (void)chown(filename, stats->st_uid, -1);
2456         (void)chown(filename, -1, stats->st_gid);
2457 #endif
2458 }
2459
2460 FLAC__Metadata_ChainStatus get_equivalent_status_(FLAC__Metadata_SimpleIteratorStatus status)
2461 {
2462         switch(status) {
2463                 case FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK:
2464                         return FLAC__METADATA_CHAIN_STATUS_OK;
2465                 case FLAC__METADATA_SIMPLE_ITERATOR_STATUS_ILLEGAL_INPUT:
2466                         return FLAC__METADATA_CHAIN_STATUS_ILLEGAL_INPUT;
2467                 case FLAC__METADATA_SIMPLE_ITERATOR_STATUS_ERROR_OPENING_FILE:
2468                         return FLAC__METADATA_CHAIN_STATUS_ERROR_OPENING_FILE;
2469                 case FLAC__METADATA_SIMPLE_ITERATOR_STATUS_NOT_A_FLAC_FILE:
2470                         return FLAC__METADATA_CHAIN_STATUS_NOT_A_FLAC_FILE;
2471                 case FLAC__METADATA_SIMPLE_ITERATOR_STATUS_NOT_WRITABLE:
2472                         return FLAC__METADATA_CHAIN_STATUS_NOT_WRITABLE;
2473                 case FLAC__METADATA_SIMPLE_ITERATOR_STATUS_BAD_METADATA:
2474                         return FLAC__METADATA_CHAIN_STATUS_BAD_METADATA;
2475                 case FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR:
2476                         return FLAC__METADATA_CHAIN_STATUS_READ_ERROR;
2477                 case FLAC__METADATA_SIMPLE_ITERATOR_STATUS_SEEK_ERROR:
2478                         return FLAC__METADATA_CHAIN_STATUS_SEEK_ERROR;
2479                 case FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR:
2480                         return FLAC__METADATA_CHAIN_STATUS_WRITE_ERROR;
2481                 case FLAC__METADATA_SIMPLE_ITERATOR_STATUS_RENAME_ERROR:
2482                         return FLAC__METADATA_CHAIN_STATUS_RENAME_ERROR;
2483                 case FLAC__METADATA_SIMPLE_ITERATOR_STATUS_UNLINK_ERROR:
2484                         return FLAC__METADATA_CHAIN_STATUS_UNLINK_ERROR;
2485                 case FLAC__METADATA_SIMPLE_ITERATOR_STATUS_MEMORY_ALLOCATION_ERROR:
2486                         return FLAC__METADATA_CHAIN_STATUS_MEMORY_ALLOCATION_ERROR;
2487                 case FLAC__METADATA_SIMPLE_ITERATOR_STATUS_INTERNAL_ERROR:
2488                 default:
2489                         return FLAC__METADATA_CHAIN_STATUS_INTERNAL_ERROR;
2490         }
2491 }