src/libFLAC/stream_decoder.c

   1 /* libFLAC - Free Lossless Audio Codec library
   2  * Copyright (C) 2000,2001,2002  Josh Coalson
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Library General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Library General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Library General Public
  15  * License along with this library; if not, write to the
  16  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17  * Boston, MA  02111-1307, USA.
  18  */
  19
  20 #include <stdio.h>
  21 #include <stdlib.h> /* for malloc() */
  22 #include <string.h> /* for memset/memcpy() */
  23 #include "FLAC/assert.h"
  24 #include "protected/stream_decoder.h"
  25 #include "private/bitbuffer.h"
  26 #include "private/cpu.h"
  27 #include "private/crc.h"
  28 #include "private/fixed.h"
  29 #include "private/format.h"
  30 #include "private/lpc.h"
  31
  32 #ifdef max
  33 #undef max
  34 #endif
  35 #define max(a,b) ((a)>(b)?(a):(b))
  36
  37 /***********************************************************************
  38  *
  39  * Private static data
  40  *
  41  ***********************************************************************/
  42
  43 static FLAC__byte ID3V2_TAG_[3] = { 'I', 'D', '3' };
  44
  45 /***********************************************************************
  46  *
  47  * Private class method prototypes
  48  *
  49  ***********************************************************************/
  50
  51 static void set_defaults_(FLAC__StreamDecoder *decoder);
  52 static FLAC__bool allocate_output_(FLAC__StreamDecoder *decoder, unsigned size, unsigned channels);
  53 static FLAC__bool has_id_filtered_(FLAC__StreamDecoder *decoder, FLAC__byte *id);
  54 static FLAC__bool find_metadata_(FLAC__StreamDecoder *decoder);
  55 static FLAC__bool read_metadata_(FLAC__StreamDecoder *decoder);
  56 static FLAC__bool skip_id3v2_tag_(FLAC__StreamDecoder *decoder);
  57 static FLAC__bool frame_sync_(FLAC__StreamDecoder *decoder);
  58 static FLAC__bool read_frame_(FLAC__StreamDecoder *decoder, FLAC__bool *got_a_frame);
  59 static FLAC__bool read_frame_header_(FLAC__StreamDecoder *decoder);
  60 static FLAC__bool read_subframe_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps);
  61 static FLAC__bool read_subframe_constant_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps);
  62 static FLAC__bool read_subframe_fixed_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, const unsigned order);
  63 static FLAC__bool read_subframe_lpc_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, const unsigned order);
  64 static FLAC__bool read_subframe_verbatim_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps);
  65 static FLAC__bool read_residual_partitioned_rice_(FLAC__StreamDecoder *decoder, unsigned predictor_order, unsigned partition_order, FLAC__EntropyCodingMethod_PartitionedRiceContents *partitioned_rice_contents, FLAC__int32 *residual);
  66 static FLAC__bool read_zero_padding_(FLAC__StreamDecoder *decoder);
  67 static FLAC__bool read_callback_(FLAC__byte buffer[], unsigned *bytes, void *client_data);
  68
  69 /***********************************************************************
  70  *
  71  * Private class data
  72  *
  73  ***********************************************************************/
  74
  75 typedef struct FLAC__StreamDecoderPrivate {
  76         FLAC__StreamDecoderReadCallback read_callback;
  77         FLAC__StreamDecoderWriteCallback write_callback;
  78         FLAC__StreamDecoderMetadataCallback metadata_callback;
  79         FLAC__StreamDecoderErrorCallback error_callback;
  80         void (*local_lpc_restore_signal)(const FLAC__int32 residual[], unsigned data_len, const FLAC__int32 qlp_coeff[], unsigned order, int lp_quantization, FLAC__int32 data[]);
  81         void (*local_lpc_restore_signal_64bit)(const FLAC__int32 residual[], unsigned data_len, const FLAC__int32 qlp_coeff[], unsigned order, int lp_quantization, FLAC__int32 data[]);
  82         void (*local_lpc_restore_signal_16bit)(const FLAC__int32 residual[], unsigned data_len, const FLAC__int32 qlp_coeff[], unsigned order, int lp_quantization, FLAC__int32 data[]);
  83         void *client_data;
  84         FLAC__BitBuffer *input;
  85         FLAC__int32 *output[FLAC__MAX_CHANNELS];
  86         FLAC__int32 *residual[FLAC__MAX_CHANNELS];
  87         FLAC__EntropyCodingMethod_PartitionedRiceContents partitioned_rice_contents[FLAC__MAX_CHANNELS];
  88         unsigned output_capacity, output_channels;
  89         FLAC__uint32 last_frame_number;
  90         FLAC__uint64 samples_decoded;
  91         FLAC__bool has_stream_info, has_seek_table;
  92         FLAC__StreamMetadata stream_info;
  93         FLAC__StreamMetadata seek_table;
  94         FLAC__bool metadata_filter[FLAC__METADATA_TYPE_VORBIS_COMMENT+1];
  95         FLAC__byte *metadata_filter_ids;
  96         unsigned metadata_filter_ids_count, metadata_filter_ids_capacity; /* units for both are IDs, not bytes */
  97         FLAC__Frame frame;
  98         FLAC__bool cached; /* true if there is a byte in lookahead */
  99         FLAC__CPUInfo cpuinfo;
 100         FLAC__byte header_warmup[2]; /* contains the sync code and reserved bits */
 101         FLAC__byte lookahead; /* temp storage when we need to look ahead one byte in the stream */
 102 } FLAC__StreamDecoderPrivate;
 103
 104 /***********************************************************************
 105  *
 106  * Public static class data
 107  *
 108  ***********************************************************************/
 109
 110 FLAC_API const char * const FLAC__StreamDecoderStateString[] = {
 111         "FLAC__STREAM_DECODER_SEARCH_FOR_METADATA",
 112         "FLAC__STREAM_DECODER_READ_METADATA",
 113         "FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC",
 114         "FLAC__STREAM_DECODER_READ_FRAME",
 115         "FLAC__STREAM_DECODER_END_OF_STREAM",
 116         "FLAC__STREAM_DECODER_ABORTED",
 117         "FLAC__STREAM_DECODER_UNPARSEABLE_STREAM",
 118         "FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR",
 119         "FLAC__STREAM_DECODER_ALREADY_INITIALIZED",
 120         "FLAC__STREAM_DECODER_INVALID_CALLBACK",
 121         "FLAC__STREAM_DECODER_UNINITIALIZED"
 122 };
 123
 124 FLAC_API const char * const FLAC__StreamDecoderReadStatusString[] = {
 125         "FLAC__STREAM_DECODER_READ_STATUS_CONTINUE",
 126         "FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM",
 127         "FLAC__STREAM_DECODER_READ_STATUS_ABORT"
 128 };
 129
 130 FLAC_API const char * const FLAC__StreamDecoderWriteStatusString[] = {
 131         "FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE",
 132         "FLAC__STREAM_DECODER_WRITE_STATUS_ABORT"
 133 };
 134
 135 FLAC_API const char * const FLAC__StreamDecoderErrorStatusString[] = {
 136         "FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC",
 137         "FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER",
 138         "FLAC__STREAM_DECODER_ERROR_STATUS_FRAME_CRC_MISMATCH"
 139 };
 140
 141 /***********************************************************************
 142  *
 143  * Class constructor/destructor
 144  *
 145  ***********************************************************************/
 146 FLAC_API FLAC__StreamDecoder *FLAC__stream_decoder_new()
 147 {
 148         FLAC__StreamDecoder *decoder;
 149         unsigned i;
 150
 151         FLAC__ASSERT(sizeof(int) >= 4); /* we want to die right away if this is not true */
 152
 153         decoder = (FLAC__StreamDecoder*)malloc(sizeof(FLAC__StreamDecoder));
 154         if(decoder == 0) {
 155                 return 0;
 156         }
 157         memset(decoder, 0, sizeof(FLAC__StreamDecoder));
 158
 159         decoder->protected_ = (FLAC__StreamDecoderProtected*)malloc(sizeof(FLAC__StreamDecoderProtected));
 160         if(decoder->protected_ == 0) {
 161                 free(decoder);
 162                 return 0;
 163         }
 164         memset(decoder->protected_, 0, sizeof(FLAC__StreamDecoderProtected));
 165
 166         decoder->private_ = (FLAC__StreamDecoderPrivate*)malloc(sizeof(FLAC__StreamDecoderPrivate));
 167         if(decoder->private_ == 0) {
 168                 free(decoder->protected_);
 169                 free(decoder);
 170                 return 0;
 171         }
 172         memset(decoder->private_, 0, sizeof(FLAC__StreamDecoderPrivate));
 173
 174         decoder->private_->input = FLAC__bitbuffer_new();
 175         if(decoder->private_->input == 0) {
 176                 free(decoder->private_);
 177                 free(decoder->protected_);
 178                 free(decoder);
 179                 return 0;
 180         }
 181
 182         decoder->private_->metadata_filter_ids_capacity = 16;
 183         if(0 == (decoder->private_->metadata_filter_ids = malloc((FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8) * decoder->private_->metadata_filter_ids_capacity))) {
 184                 FLAC__bitbuffer_delete(decoder->private_->input);
 185                 free(decoder->private_);
 186                 free(decoder->protected_);
 187                 free(decoder);
 188                 return 0;
 189         }
 190
 191         for(i = 0; i < FLAC__MAX_CHANNELS; i++) {
 192                 decoder->private_->output[i] = 0;
 193                 decoder->private_->residual[i] = 0;
 194         }
 195
 196         decoder->private_->output_capacity = 0;
 197         decoder->private_->output_channels = 0;
 198         decoder->private_->has_seek_table = false;
 199
 200         for(i = 0; i < FLAC__MAX_CHANNELS; i++)
 201                 FLAC__format_entropy_coding_method_partitioned_rice_contents_init(&decoder->private_->partitioned_rice_contents[i]);
 202
 203         set_defaults_(decoder);
 204
 205         decoder->protected_->state = FLAC__STREAM_DECODER_UNINITIALIZED;
 206
 207         return decoder;
 208 }
 209
 210 FLAC_API void FLAC__stream_decoder_delete(FLAC__StreamDecoder *decoder)
 211 {
 212         unsigned i;
 213
 214         FLAC__ASSERT(0 != decoder);
 215         FLAC__ASSERT(0 != decoder->protected_);
 216         FLAC__ASSERT(0 != decoder->private_);
 217         FLAC__ASSERT(0 != decoder->private_->input);
 218
 219         FLAC__stream_decoder_finish(decoder);
 220
 221         if(0 != decoder->private_->metadata_filter_ids)
 222                 free(decoder->private_->metadata_filter_ids);
 223
 224         FLAC__bitbuffer_delete(decoder->private_->input);
 225
 226         for(i = 0; i < FLAC__MAX_CHANNELS; i++)
 227                 FLAC__format_entropy_coding_method_partitioned_rice_contents_clear(&decoder->private_->partitioned_rice_contents[i]);
 228
 229         free(decoder->private_);
 230         free(decoder->protected_);
 231         free(decoder);
 232 }
 233
 234 /***********************************************************************
 235  *
 236  * Public class methods
 237  *
 238  ***********************************************************************/
 239
 240 FLAC_API FLAC__StreamDecoderState FLAC__stream_decoder_init(FLAC__StreamDecoder *decoder)
 241 {
 242         FLAC__ASSERT(0 != decoder);
 243
 244         if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
 245                 return decoder->protected_->state = FLAC__STREAM_DECODER_ALREADY_INITIALIZED;
 246
 247         if(0 == decoder->private_->read_callback || 0 == decoder->private_->write_callback || 0 == decoder->private_->metadata_callback || 0 == decoder->private_->error_callback)
 248                 return decoder->protected_->state = FLAC__STREAM_DECODER_INVALID_CALLBACK;
 249
 250         if(!FLAC__bitbuffer_init(decoder->private_->input))
 251                 return decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
 252
 253         decoder->private_->last_frame_number = 0;
 254         decoder->private_->samples_decoded = 0;
 255         decoder->private_->has_stream_info = false;
 256         decoder->private_->cached = false;
 257
 258         /*
 259          * get the CPU info and set the function pointers
 260          */
 261         FLAC__cpu_info(&decoder->private_->cpuinfo);
 262         /* first default to the non-asm routines */
 263         decoder->private_->local_lpc_restore_signal = FLAC__lpc_restore_signal;
 264         decoder->private_->local_lpc_restore_signal_64bit = FLAC__lpc_restore_signal_wide;
 265         decoder->private_->local_lpc_restore_signal_16bit = FLAC__lpc_restore_signal;
 266         /* now override with asm where appropriate */
 267 #ifndef FLAC__NO_ASM
 268         if(decoder->private_->cpuinfo.use_asm) {
 269 #ifdef FLAC__CPU_IA32
 270                 FLAC__ASSERT(decoder->private_->cpuinfo.type == FLAC__CPUINFO_TYPE_IA32);
 271 #ifdef FLAC__HAS_NASM
 272                 if(decoder->private_->cpuinfo.data.ia32.mmx) {
 273                         decoder->private_->local_lpc_restore_signal = FLAC__lpc_restore_signal_asm_ia32;
 274                         decoder->private_->local_lpc_restore_signal_16bit = FLAC__lpc_restore_signal_asm_ia32_mmx;
 275                 }
 276                 else {
 277                         decoder->private_->local_lpc_restore_signal = FLAC__lpc_restore_signal_asm_ia32;
 278                         decoder->private_->local_lpc_restore_signal_16bit = FLAC__lpc_restore_signal_asm_ia32;
 279                 }
 280 #endif
 281 #endif
 282         }
 283 #endif
 284
 285         if(!FLAC__stream_decoder_reset(decoder))
 286                 return decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
 287
 288         return decoder->protected_->state;
 289 }
 290
 291 FLAC_API void FLAC__stream_decoder_finish(FLAC__StreamDecoder *decoder)
 292 {
 293         unsigned i;
 294         FLAC__ASSERT(0 != decoder);
 295         if(decoder->protected_->state == FLAC__STREAM_DECODER_UNINITIALIZED)
 296                 return;
 297         if(decoder->private_->has_seek_table) {
 298                 FLAC__ASSERT(0 != decoder->private_->seek_table.data.seek_table.points);
 299                 free(decoder->private_->seek_table.data.seek_table.points);
 300                 decoder->private_->seek_table.data.seek_table.points = 0;
 301                 decoder->private_->has_seek_table = false;
 302         }
 303         FLAC__bitbuffer_free(decoder->private_->input);
 304         for(i = 0; i < FLAC__MAX_CHANNELS; i++) {
 305                 /* WATCHOUT:
 306                  * FLAC__lpc_restore_signal_asm_ia32_mmx() requires that the
 307                  * output arrays have a buffer of up to 3 zeroes in front
 308                  * (at negative indices) for alignment purposes; we use 4
 309                  * to keep the data well-aligned.
 310                  */
 311                 if(0 != decoder->private_->output[i]) {
 312                         free(decoder->private_->output[i]-4);
 313                         decoder->private_->output[i] = 0;
 314                 }
 315                 if(0 != decoder->private_->residual[i]) {
 316                         free(decoder->private_->residual[i]);
 317                         decoder->private_->residual[i] = 0;
 318                 }
 319         }
 320         decoder->private_->output_capacity = 0;
 321         decoder->private_->output_channels = 0;
 322
 323         set_defaults_(decoder);
 324
 325         decoder->protected_->state = FLAC__STREAM_DECODER_UNINITIALIZED;
 326 }
 327
 328 FLAC_API FLAC__bool FLAC__stream_decoder_set_read_callback(FLAC__StreamDecoder *decoder, FLAC__StreamDecoderReadCallback value)
 329 {
 330         FLAC__ASSERT(0 != decoder);
 331         FLAC__ASSERT(0 != decoder->private_);
 332         FLAC__ASSERT(0 != decoder->protected_);
 333         if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
 334                 return false;
 335         decoder->private_->read_callback = value;
 336         return true;
 337 }
 338
 339 FLAC_API FLAC__bool FLAC__stream_decoder_set_write_callback(FLAC__StreamDecoder *decoder, FLAC__StreamDecoderWriteCallback value)
 340 {
 341         FLAC__ASSERT(0 != decoder);
 342         FLAC__ASSERT(0 != decoder->private_);
 343         FLAC__ASSERT(0 != decoder->protected_);
 344         if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
 345                 return false;
 346         decoder->private_->write_callback = value;
 347         return true;
 348 }
 349
 350 FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_callback(FLAC__StreamDecoder *decoder, FLAC__StreamDecoderMetadataCallback value)
 351 {
 352         FLAC__ASSERT(0 != decoder);
 353         FLAC__ASSERT(0 != decoder->private_);
 354         FLAC__ASSERT(0 != decoder->protected_);
 355         if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
 356                 return false;
 357         decoder->private_->metadata_callback = value;
 358         return true;
 359 }
 360
 361 FLAC_API FLAC__bool FLAC__stream_decoder_set_error_callback(FLAC__StreamDecoder *decoder, FLAC__StreamDecoderErrorCallback value)
 362 {
 363         FLAC__ASSERT(0 != decoder);
 364         FLAC__ASSERT(0 != decoder->private_);
 365         FLAC__ASSERT(0 != decoder->protected_);
 366         if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
 367                 return false;
 368         decoder->private_->error_callback = value;
 369         return true;
 370 }
 371
 372 FLAC_API FLAC__bool FLAC__stream_decoder_set_client_data(FLAC__StreamDecoder *decoder, void *value)
 373 {
 374         FLAC__ASSERT(0 != decoder);
 375         FLAC__ASSERT(0 != decoder->private_);
 376         FLAC__ASSERT(0 != decoder->protected_);
 377         if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
 378                 return false;
 379         decoder->private_->client_data = value;
 380         return true;
 381 }
 382
 383 FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_respond(FLAC__StreamDecoder *decoder, FLAC__MetadataType type)
 384 {
 385         FLAC__ASSERT(0 != decoder);
 386         FLAC__ASSERT(0 != decoder->private_);
 387         FLAC__ASSERT(0 != decoder->protected_);
 388         FLAC__ASSERT(type <= FLAC__METADATA_TYPE_VORBIS_COMMENT);
 389         if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
 390                 return false;
 391         decoder->private_->metadata_filter[type] = true;
 392         if(type == FLAC__METADATA_TYPE_APPLICATION)
 393                 decoder->private_->metadata_filter_ids_count = 0;
 394         return true;
 395 }
 396
 397 FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_respond_application(FLAC__StreamDecoder *decoder, const FLAC__byte id[4])
 398 {
 399         FLAC__ASSERT(0 != decoder);
 400         FLAC__ASSERT(0 != decoder->private_);
 401         FLAC__ASSERT(0 != decoder->protected_);
 402         FLAC__ASSERT(0 != id);
 403         if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
 404                 return false;
 405
 406         if(decoder->private_->metadata_filter[FLAC__METADATA_TYPE_APPLICATION])
 407                 return true;
 408
 409         FLAC__ASSERT(0 != decoder->private_->metadata_filter_ids);
 410
 411         if(decoder->private_->metadata_filter_ids_count == decoder->private_->metadata_filter_ids_capacity) {
 412                 if(0 == (decoder->private_->metadata_filter_ids = realloc(decoder->private_->metadata_filter_ids, decoder->private_->metadata_filter_ids_capacity * 2)))
 413                         return decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
 414                 decoder->private_->metadata_filter_ids_capacity *= 2;
 415         }
 416
 417         memcpy(decoder->private_->metadata_filter_ids + decoder->private_->metadata_filter_ids_count * (FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8), id, (FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8));
 418         decoder->private_->metadata_filter_ids_count++;
 419
 420         return true;
 421 }
 422
 423 FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_respond_all(FLAC__StreamDecoder *decoder)
 424 {
 425         unsigned i;
 426         FLAC__ASSERT(0 != decoder);
 427         FLAC__ASSERT(0 != decoder->private_);
 428         FLAC__ASSERT(0 != decoder->protected_);
 429         if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
 430                 return false;
 431         for(i = 0; i < sizeof(decoder->private_->metadata_filter) / sizeof(decoder->private_->metadata_filter[0]); i++)
 432                 decoder->private_->metadata_filter[i] = true;
 433         decoder->private_->metadata_filter_ids_count = 0;
 434         return true;
 435 }
 436
 437 FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_ignore(FLAC__StreamDecoder *decoder, FLAC__MetadataType type)
 438 {
 439         FLAC__ASSERT(0 != decoder);
 440         FLAC__ASSERT(0 != decoder->private_);
 441         FLAC__ASSERT(0 != decoder->protected_);
 442         FLAC__ASSERT(type <= FLAC__METADATA_TYPE_VORBIS_COMMENT);
 443         if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
 444                 return false;
 445         decoder->private_->metadata_filter[type] = false;
 446         if(type == FLAC__METADATA_TYPE_APPLICATION)
 447                 decoder->private_->metadata_filter_ids_count = 0;
 448         return true;
 449 }
 450
 451 FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_ignore_application(FLAC__StreamDecoder *decoder, const FLAC__byte id[4])
 452 {
 453         FLAC__ASSERT(0 != decoder);
 454         FLAC__ASSERT(0 != decoder->private_);
 455         FLAC__ASSERT(0 != decoder->protected_);
 456         FLAC__ASSERT(0 != id);
 457         if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
 458                 return false;
 459
 460         if(!decoder->private_->metadata_filter[FLAC__METADATA_TYPE_APPLICATION])
 461                 return true;
 462
 463         FLAC__ASSERT(0 != decoder->private_->metadata_filter_ids);
 464
 465         if(decoder->private_->metadata_filter_ids_count == decoder->private_->metadata_filter_ids_capacity) {
 466                 if(0 == (decoder->private_->metadata_filter_ids = realloc(decoder->private_->metadata_filter_ids, decoder->private_->metadata_filter_ids_capacity * 2)))
 467                         return decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
 468                 decoder->private_->metadata_filter_ids_capacity *= 2;
 469         }
 470
 471         memcpy(decoder->private_->metadata_filter_ids + decoder->private_->metadata_filter_ids_count * (FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8), id, (FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8));
 472         decoder->private_->metadata_filter_ids_count++;
 473
 474         return true;
 475 }
 476
 477 FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_ignore_all(FLAC__StreamDecoder *decoder)
 478 {
 479         FLAC__ASSERT(0 != decoder);
 480         FLAC__ASSERT(0 != decoder->private_);
 481         FLAC__ASSERT(0 != decoder->protected_);
 482         if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
 483                 return false;
 484         memset(decoder->private_->metadata_filter, 0, sizeof(decoder->private_->metadata_filter));
 485         decoder->private_->metadata_filter_ids_count = 0;
 486         return true;
 487 }
 488
 489 FLAC_API FLAC__StreamDecoderState FLAC__stream_decoder_get_state(const FLAC__StreamDecoder *decoder)
 490 {
 491         FLAC__ASSERT(0 != decoder);
 492         FLAC__ASSERT(0 != decoder->protected_);
 493         return decoder->protected_->state;
 494 }
 495
 496 FLAC_API unsigned FLAC__stream_decoder_get_channels(const FLAC__StreamDecoder *decoder)
 497 {
 498         FLAC__ASSERT(0 != decoder);
 499         FLAC__ASSERT(0 != decoder->protected_);
 500         return decoder->protected_->channels;
 501 }
 502
 503 FLAC_API FLAC__ChannelAssignment FLAC__stream_decoder_get_channel_assignment(const FLAC__StreamDecoder *decoder)
 504 {
 505         FLAC__ASSERT(0 != decoder);
 506         FLAC__ASSERT(0 != decoder->protected_);
 507         return decoder->protected_->channel_assignment;
 508 }
 509
 510 FLAC_API unsigned FLAC__stream_decoder_get_bits_per_sample(const FLAC__StreamDecoder *decoder)
 511 {
 512         FLAC__ASSERT(0 != decoder);
 513         FLAC__ASSERT(0 != decoder->protected_);
 514         return decoder->protected_->bits_per_sample;
 515 }
 516
 517 FLAC_API unsigned FLAC__stream_decoder_get_sample_rate(const FLAC__StreamDecoder *decoder)
 518 {
 519         FLAC__ASSERT(0 != decoder);
 520         FLAC__ASSERT(0 != decoder->protected_);
 521         return decoder->protected_->sample_rate;
 522 }
 523
 524 FLAC_API unsigned FLAC__stream_decoder_get_blocksize(const FLAC__StreamDecoder *decoder)
 525 {
 526         FLAC__ASSERT(0 != decoder);
 527         FLAC__ASSERT(0 != decoder->protected_);
 528         return decoder->protected_->blocksize;
 529 }
 530
 531 FLAC_API FLAC__bool FLAC__stream_decoder_flush(FLAC__StreamDecoder *decoder)
 532 {
 533         FLAC__ASSERT(0 != decoder);
 534         FLAC__ASSERT(0 != decoder->private_);
 535         FLAC__ASSERT(0 != decoder->protected_);
 536
 537         if(!FLAC__bitbuffer_clear(decoder->private_->input)) {
 538                 decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
 539                 return false;
 540         }
 541         decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
 542
 543         return true;
 544 }
 545
 546 FLAC_API FLAC__bool FLAC__stream_decoder_reset(FLAC__StreamDecoder *decoder)
 547 {
 548         FLAC__ASSERT(0 != decoder);
 549         FLAC__ASSERT(0 != decoder->private_);
 550         FLAC__ASSERT(0 != decoder->protected_);
 551
 552         if(!FLAC__stream_decoder_flush(decoder)) {
 553                 decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
 554                 return false;
 555         }
 556         decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_METADATA;
 557
 558         decoder->private_->samples_decoded = 0;
 559
 560         return true;
 561 }
 562
 563 FLAC_API FLAC__bool FLAC__stream_decoder_process_single(FLAC__StreamDecoder *decoder)
 564 {
 565         FLAC__bool got_a_frame;
 566         FLAC__ASSERT(0 != decoder);
 567         FLAC__ASSERT(0 != decoder->protected_);
 568
 569         while(1) {
 570                 switch(decoder->protected_->state) {
 571                         case FLAC__STREAM_DECODER_SEARCH_FOR_METADATA:
 572                                 if(!find_metadata_(decoder))
 573                                         return false; /* above function sets the status for us */
 574                                 break;
 575                         case FLAC__STREAM_DECODER_READ_METADATA:
 576                                 if(!read_metadata_(decoder))
 577                                         return false; /* above function sets the status for us */
 578                                 else
 579                                         return true;
 580                         case FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC:
 581                                 if(!frame_sync_(decoder))
 582                                         return true; /* above function sets the status for us */
 583                                 break;
 584                         case FLAC__STREAM_DECODER_READ_FRAME:
 585                                 if(!read_frame_(decoder, &got_a_frame))
 586                                         return false; /* above function sets the status for us */
 587                                 if(got_a_frame)
 588                                         return true; /* above function sets the status for us */
 589                                 break;
 590                         case FLAC__STREAM_DECODER_END_OF_STREAM:
 591                         case FLAC__STREAM_DECODER_ABORTED:
 592                                 return true;
 593                         default:
 594                                 FLAC__ASSERT(0);
 595                                 return false;
 596                 }
 597         }
 598 }
 599
 600 FLAC_API FLAC__bool FLAC__stream_decoder_process_until_end_of_metadata(FLAC__StreamDecoder *decoder)
 601 {
 602         FLAC__ASSERT(0 != decoder);
 603         FLAC__ASSERT(0 != decoder->protected_);
 604
 605         while(1) {
 606                 switch(decoder->protected_->state) {
 607                         case FLAC__STREAM_DECODER_SEARCH_FOR_METADATA:
 608                                 if(!find_metadata_(decoder))
 609                                         return false; /* above function sets the status for us */
 610                                 break;
 611                         case FLAC__STREAM_DECODER_READ_METADATA:
 612                                 if(!read_metadata_(decoder))
 613                                         return false; /* above function sets the status for us */
 614                                 break;
 615                         case FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC:
 616                         case FLAC__STREAM_DECODER_READ_FRAME:
 617                         case FLAC__STREAM_DECODER_END_OF_STREAM:
 618                         case FLAC__STREAM_DECODER_ABORTED:
 619                                 return true;
 620                         default:
 621                                 FLAC__ASSERT(0);
 622                                 return false;
 623                 }
 624         }
 625 }
 626
 627 FLAC_API FLAC__bool FLAC__stream_decoder_process_until_end_of_stream(FLAC__StreamDecoder *decoder)
 628 {
 629         FLAC__bool dummy;
 630         FLAC__ASSERT(0 != decoder);
 631         FLAC__ASSERT(0 != decoder->protected_);
 632
 633         while(1) {
 634                 switch(decoder->protected_->state) {
 635                         case FLAC__STREAM_DECODER_SEARCH_FOR_METADATA:
 636                                 if(!find_metadata_(decoder))
 637                                         return false; /* above function sets the status for us */
 638                                 break;
 639                         case FLAC__STREAM_DECODER_READ_METADATA:
 640                                 if(!read_metadata_(decoder))
 641                                         return false; /* above function sets the status for us */
 642                                 break;
 643                         case FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC:
 644                                 if(!frame_sync_(decoder))
 645                                         return true; /* above function sets the status for us */
 646                                 break;
 647                         case FLAC__STREAM_DECODER_READ_FRAME:
 648                                 if(!read_frame_(decoder, &dummy))
 649                                         return false; /* above function sets the status for us */
 650                                 break;
 651                         case FLAC__STREAM_DECODER_END_OF_STREAM:
 652                         case FLAC__STREAM_DECODER_ABORTED:
 653                                 return true;
 654                         default:
 655                                 FLAC__ASSERT(0);
 656                                 return false;
 657                 }
 658         }
 659 }
 660
 661 /***********************************************************************
 662  *
 663  * Protected class methods
 664  *
 665  ***********************************************************************/
 666
 667 unsigned FLAC__stream_decoder_get_input_bytes_unconsumed(const FLAC__StreamDecoder *decoder)
 668 {
 669         FLAC__ASSERT(0 != decoder);
 670         return FLAC__bitbuffer_get_input_bytes_unconsumed(decoder->private_->input);
 671 }
 672
 673 /***********************************************************************
 674  *
 675  * Private class methods
 676  *
 677  ***********************************************************************/
 678
 679 void set_defaults_(FLAC__StreamDecoder *decoder)
 680 {
 681         decoder->private_->read_callback = 0;
 682         decoder->private_->write_callback = 0;
 683         decoder->private_->metadata_callback = 0;
 684         decoder->private_->error_callback = 0;
 685         decoder->private_->client_data = 0;
 686
 687         memset(decoder->private_->metadata_filter, 0, sizeof(decoder->private_->metadata_filter));
 688         decoder->private_->metadata_filter[FLAC__METADATA_TYPE_STREAMINFO] = true;
 689         decoder->private_->metadata_filter_ids_count = 0;
 690 }
 691
 692 FLAC__bool allocate_output_(FLAC__StreamDecoder *decoder, unsigned size, unsigned channels)
 693 {
 694         unsigned i;
 695         FLAC__int32 *tmp;
 696
 697         if(size <= decoder->private_->output_capacity && channels <= decoder->private_->output_channels)
 698                 return true;
 699
 700         /* simply using realloc() is not practical because the number of channels may change mid-stream */
 701
 702         for(i = 0; i < FLAC__MAX_CHANNELS; i++) {
 703                 if(0 != decoder->private_->output[i]) {
 704                         free(decoder->private_->output[i]);
 705                         decoder->private_->output[i] = 0;
 706                 }
 707                 if(0 != decoder->private_->residual[i]) {
 708                         free(decoder->private_->residual[i]);
 709                         decoder->private_->residual[i] = 0;
 710                 }
 711         }
 712
 713         for(i = 0; i < channels; i++) {
 714                 /* WATCHOUT:
 715                  * FLAC__lpc_restore_signal_asm_ia32_mmx() requires that the
 716                  * output arrays have a buffer of up to 3 zeroes in front
 717                  * (at negative indices) for alignment purposes; we use 4
 718                  * to keep the data well-aligned.
 719                  */
 720                 tmp = (FLAC__int32*)malloc(sizeof(FLAC__int32)*(size+4));
 721                 if(tmp == 0) {
 722                         decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
 723                         return false;
 724                 }
 725                 memset(tmp, 0, sizeof(FLAC__int32)*4);
 726                 decoder->private_->output[i] = tmp + 4;
 727
 728                 tmp = (FLAC__int32*)malloc(sizeof(FLAC__int32)*size);
 729                 if(tmp == 0) {
 730                         decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
 731                         return false;
 732                 }
 733                 decoder->private_->residual[i] = tmp;
 734         }
 735
 736         decoder->private_->output_capacity = size;
 737         decoder->private_->output_channels = channels;
 738
 739         return true;
 740 }
 741
 742 FLAC__bool has_id_filtered_(FLAC__StreamDecoder *decoder, FLAC__byte *id)
 743 {
 744         unsigned i;
 745
 746         FLAC__ASSERT(0 != decoder);
 747         FLAC__ASSERT(0 != decoder->private_);
 748
 749         for(i = 0; i < decoder->private_->metadata_filter_ids_count; i++)
 750                 if(0 == memcmp(decoder->private_->metadata_filter_ids + i * (FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8), id, (FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8)))
 751                         return true;
 752
 753         return false;
 754 }
 755
 756 FLAC__bool find_metadata_(FLAC__StreamDecoder *decoder)
 757 {
 758         FLAC__uint32 x;
 759         unsigned i, id;
 760         FLAC__bool first = true;
 761
 762         FLAC__ASSERT(FLAC__bitbuffer_is_consumed_byte_aligned(decoder->private_->input));
 763
 764         for(i = id = 0; i < 4; ) {
 765                 if(decoder->private_->cached) {
 766                         x = (FLAC__uint32)decoder->private_->lookahead;
 767                         decoder->private_->cached = false;
 768                 }
 769                 else {
 770                         if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &x, 8, read_callback_, decoder))
 771                                 return false; /* the read_callback_ sets the state for us */
 772                 }
 773                 if(x == FLAC__STREAM_SYNC_STRING[i]) {
 774                         first = true;
 775                         i++;
 776                         id = 0;
 777                         continue;
 778                 }
 779                 if(x == ID3V2_TAG_[id]) {
 780                         id++;
 781                         i = 0;
 782                         if(id == 3) {
 783                                 if(!skip_id3v2_tag_(decoder))
 784                                         return false; /* the read_callback_ sets the state for us */
 785                         }
 786                         continue;
 787                 }
 788                 if(x == 0xff) { /* MAGIC NUMBER for the first 8 frame sync bits */
 789                         decoder->private_->header_warmup[0] = (FLAC__byte)x;
 790                         if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &x, 8, read_callback_, decoder))
 791                                 return false; /* the read_callback_ sets the state for us */
 792
 793                         /* we have to check if we just read two 0xff's in a row; the second may actually be the beginning of the sync code */
 794                         /* else we have to check if the second byte is the end of a sync code */
 795                         if(x == 0xff) { /* MAGIC NUMBER for the first 8 frame sync bits */
 796                                 decoder->private_->lookahead = (FLAC__byte)x;
 797                                 decoder->private_->cached = true;
 798                         }
 799                         else if(x >> 2 == 0x3e) { /* MAGIC NUMBER for the last 6 sync bits */
 800                                 decoder->private_->header_warmup[1] = (FLAC__byte)x;
 801                                 decoder->protected_->state = FLAC__STREAM_DECODER_READ_FRAME;
 802                                 return true;
 803                         }
 804                 }
 805                 i = 0;
 806                 if(first) {
 807                         decoder->private_->error_callback(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC, decoder->private_->client_data);
 808                         first = false;
 809                 }
 810         }
 811
 812         decoder->protected_->state = FLAC__STREAM_DECODER_READ_METADATA;
 813         return true;
 814 }
 815
 816 FLAC__bool read_metadata_(FLAC__StreamDecoder *decoder)
 817 {
 818         FLAC__uint32 i, x, last_block, type, length;
 819         FLAC__uint64 xx;
 820
 821         FLAC__ASSERT(FLAC__bitbuffer_is_consumed_byte_aligned(decoder->private_->input));
 822
 823         if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &last_block, FLAC__STREAM_METADATA_IS_LAST_LEN, read_callback_, decoder))
 824                 return false; /* the read_callback_ sets the state for us */
 825         if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &type, FLAC__STREAM_METADATA_TYPE_LEN, read_callback_, decoder))
 826                 return false; /* the read_callback_ sets the state for us */
 827         if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &length, FLAC__STREAM_METADATA_LENGTH_LEN, read_callback_, decoder))
 828                 return false; /* the read_callback_ sets the state for us */
 829         if(type == FLAC__METADATA_TYPE_STREAMINFO) {
 830                 unsigned used_bits = 0;
 831                 decoder->private_->stream_info.type = type;
 832                 decoder->private_->stream_info.is_last = last_block;
 833                 decoder->private_->stream_info.length = length;
 834
 835                 if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_MIN_BLOCK_SIZE_LEN, read_callback_, decoder))
 836                         return false; /* the read_callback_ sets the state for us */
 837                 decoder->private_->stream_info.data.stream_info.min_blocksize = x;
 838                 used_bits += FLAC__STREAM_METADATA_STREAMINFO_MIN_BLOCK_SIZE_LEN;
 839
 840                 if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_MAX_BLOCK_SIZE_LEN, read_callback_, decoder))
 841                         return false; /* the read_callback_ sets the state for us */
 842                 decoder->private_->stream_info.data.stream_info.max_blocksize = x;
 843                 used_bits += FLAC__STREAM_METADATA_STREAMINFO_MAX_BLOCK_SIZE_LEN;
 844
 845                 if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_MIN_FRAME_SIZE_LEN, read_callback_, decoder))
 846                         return false; /* the read_callback_ sets the state for us */
 847                 decoder->private_->stream_info.data.stream_info.min_framesize = x;
 848                 used_bits += FLAC__STREAM_METADATA_STREAMINFO_MIN_FRAME_SIZE_LEN;
 849
 850                 if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_MAX_FRAME_SIZE_LEN, read_callback_, decoder))
 851                         return false; /* the read_callback_ sets the state for us */
 852                 decoder->private_->stream_info.data.stream_info.max_framesize = x;
 853                 used_bits += FLAC__STREAM_METADATA_STREAMINFO_MAX_FRAME_SIZE_LEN;
 854
 855                 if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_SAMPLE_RATE_LEN, read_callback_, decoder))
 856                         return false; /* the read_callback_ sets the state for us */
 857                 decoder->private_->stream_info.data.stream_info.sample_rate = x;
 858                 used_bits += FLAC__STREAM_METADATA_STREAMINFO_SAMPLE_RATE_LEN;
 859
 860                 if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_CHANNELS_LEN, read_callback_, decoder))
 861                         return false; /* the read_callback_ sets the state for us */
 862                 decoder->private_->stream_info.data.stream_info.channels = x+1;
 863                 used_bits += FLAC__STREAM_METADATA_STREAMINFO_CHANNELS_LEN;
 864
 865                 if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_BITS_PER_SAMPLE_LEN, read_callback_, decoder))
 866                         return false; /* the read_callback_ sets the state for us */
 867                 decoder->private_->stream_info.data.stream_info.bits_per_sample = x+1;
 868                 used_bits += FLAC__STREAM_METADATA_STREAMINFO_BITS_PER_SAMPLE_LEN;
 869
 870                 if(!FLAC__bitbuffer_read_raw_uint64(decoder->private_->input, &decoder->private_->stream_info.data.stream_info.total_samples, FLAC__STREAM_METADATA_STREAMINFO_TOTAL_SAMPLES_LEN, read_callback_, decoder))
 871                         return false; /* the read_callback_ sets the state for us */
 872                 used_bits += FLAC__STREAM_METADATA_STREAMINFO_TOTAL_SAMPLES_LEN;
 873
 874                 if(!FLAC__bitbuffer_read_byte_block_aligned(decoder->private_->input, decoder->private_->stream_info.data.stream_info.md5sum, 16, read_callback_, decoder))
 875                         return false; /* the read_callback_ sets the state for us */
 876                 used_bits += 16*8;
 877
 878                 /* skip the rest of the block */
 879                 FLAC__ASSERT(used_bits % 8 == 0);
 880                 length -= (used_bits / 8);
 881                 if(!FLAC__bitbuffer_read_byte_block_aligned(decoder->private_->input, 0, length, read_callback_, decoder))
 882                         return false; /* the read_callback_ sets the state for us */
 883
 884                 decoder->private_->has_stream_info = true;
 885                 if(decoder->private_->metadata_filter[FLAC__METADATA_TYPE_STREAMINFO])
 886                         decoder->private_->metadata_callback(decoder, &decoder->private_->stream_info, decoder->private_->client_data);
 887         }
 888         else if(type == FLAC__METADATA_TYPE_SEEKTABLE) {
 889                 decoder->private_->seek_table.type = type;
 890                 decoder->private_->seek_table.is_last = last_block;
 891                 decoder->private_->seek_table.length = length;
 892
 893                 decoder->private_->seek_table.data.seek_table.num_points = length / FLAC__STREAM_METADATA_SEEKPOINT_LENGTH;
 894
 895                 if(0 == (decoder->private_->seek_table.data.seek_table.points = (FLAC__StreamMetadata_SeekPoint*)malloc(decoder->private_->seek_table.data.seek_table.num_points * sizeof(FLAC__StreamMetadata_SeekPoint)))) {
 896                         decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
 897                         return false;
 898                 }
 899                 for(i = 0; i < decoder->private_->seek_table.data.seek_table.num_points; i++) {
 900                         if(!FLAC__bitbuffer_read_raw_uint64(decoder->private_->input, &xx, FLAC__STREAM_METADATA_SEEKPOINT_SAMPLE_NUMBER_LEN, read_callback_, decoder))
 901                                 return false; /* the read_callback_ sets the state for us */
 902                         decoder->private_->seek_table.data.seek_table.points[i].sample_number = xx;
 903
 904                         if(!FLAC__bitbuffer_read_raw_uint64(decoder->private_->input, &xx, FLAC__STREAM_METADATA_SEEKPOINT_STREAM_OFFSET_LEN, read_callback_, decoder))
 905                                 return false; /* the read_callback_ sets the state for us */
 906                         decoder->private_->seek_table.data.seek_table.points[i].stream_offset = xx;
 907
 908                         if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_SEEKPOINT_FRAME_SAMPLES_LEN, read_callback_, decoder))
 909                                 return false; /* the read_callback_ sets the state for us */
 910                         decoder->private_->seek_table.data.seek_table.points[i].frame_samples = x;
 911                 }
 912                 length -= (decoder->private_->seek_table.data.seek_table.num_points * FLAC__STREAM_METADATA_SEEKPOINT_LENGTH);
 913                 /* if there is a partial point left, skip over it */
 914                 if(length > 0) {
 915                         /*@@@ do an error_callback() here?  there's an argument for either way */
 916                         if(!FLAC__bitbuffer_read_byte_block_aligned(decoder->private_->input, 0, length, read_callback_, decoder))
 917                                 return false; /* the read_callback_ sets the state for us */
 918                 }
 919
 920                 decoder->private_->has_seek_table = true;
 921                 if(decoder->private_->metadata_filter[FLAC__METADATA_TYPE_SEEKTABLE])
 922                         decoder->private_->metadata_callback(decoder, &decoder->private_->seek_table, decoder->private_->client_data);
 923         }
 924         else {
 925                 FLAC__bool skip_it = !decoder->private_->metadata_filter[type];
 926                 unsigned real_length = length;
 927                 FLAC__StreamMetadata block;
 928
 929                 block.is_last = last_block;
 930                 block.type = type;
 931                 block.length = length;
 932
 933                 if(type == FLAC__METADATA_TYPE_APPLICATION) {
 934                         if(!FLAC__bitbuffer_read_byte_block_aligned(decoder->private_->input, block.data.application.id, FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8, read_callback_, decoder))
 935                                 return false; /* the read_callback_ sets the state for us */
 936
 937                         real_length -= FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8;
 938
 939                         if(decoder->private_->metadata_filter_ids_count > 0 && has_id_filtered_(decoder, block.data.application.id))
 940                                 skip_it = !skip_it;
 941                 }
 942
 943                 if(skip_it) {
 944                         if(!FLAC__bitbuffer_read_byte_block_aligned(decoder->private_->input, 0, real_length, read_callback_, decoder))
 945                                 return false; /* the read_callback_ sets the state for us */
 946                 }
 947                 else {
 948                         switch(type) {
 949                                 case FLAC__METADATA_TYPE_PADDING:
 950                                         /* skip the padding bytes */
 951                                         if(!FLAC__bitbuffer_read_byte_block_aligned(decoder->private_->input, 0, real_length, read_callback_, decoder))
 952                                                 return false; /* the read_callback_ sets the state for us */
 953                                         break;
 954                                 case FLAC__METADATA_TYPE_APPLICATION:
 955                                         /* remember, we read the ID already */
 956                                         if(real_length > 0) {
 957                                                 if(0 == (block.data.application.data = malloc(real_length))) {
 958                                                         decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
 959                                                         return false;
 960                                                 }
 961                                                 if(!FLAC__bitbuffer_read_byte_block_aligned(decoder->private_->input, block.data.application.data, real_length, read_callback_, decoder))
 962                                                         return false; /* the read_callback_ sets the state for us */
 963                                         }
 964                                         else
 965                                                 block.data.application.data = 0;
 966                                         break;
 967                                 case FLAC__METADATA_TYPE_VORBIS_COMMENT:
 968                                         /* read vendor string */
 969                                         FLAC__ASSERT(FLAC__STREAM_METADATA_VORBIS_COMMENT_ENTRY_LENGTH_LEN == 32);
 970                                         if(!FLAC__bitbuffer_read_raw_uint32_little_endian(decoder->private_->input, &block.data.vorbis_comment.vendor_string.length, read_callback_, decoder))
 971                                                 return false; /* the read_callback_ sets the state for us */
 972                                         if(block.data.vorbis_comment.vendor_string.length > 0) {
 973                                                 if(0 == (block.data.vorbis_comment.vendor_string.entry = malloc(block.data.vorbis_comment.vendor_string.length))) {
 974                                                         decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
 975                                                         return false;
 976                                                 }
 977                                                 if(!FLAC__bitbuffer_read_byte_block_aligned(decoder->private_->input, block.data.vorbis_comment.vendor_string.entry, block.data.vorbis_comment.vendor_string.length, read_callback_, decoder))
 978                                                         return false; /* the read_callback_ sets the state for us */
 979                                         }
 980                                         else
 981                                                 block.data.vorbis_comment.vendor_string.entry = 0;
 982
 983                                         /* read num comments */
 984                                         FLAC__ASSERT(FLAC__STREAM_METADATA_VORBIS_COMMENT_NUM_COMMENTS_LEN == 32);
 985                                         if(!FLAC__bitbuffer_read_raw_uint32_little_endian(decoder->private_->input, &block.data.vorbis_comment.num_comments, read_callback_, decoder))
 986                                                 return false; /* the read_callback_ sets the state for us */
 987
 988                                         /* read comments */
 989                                         if(block.data.vorbis_comment.num_comments > 0) {
 990                                                 if(0 == (block.data.vorbis_comment.comments = malloc(block.data.vorbis_comment.num_comments * sizeof(FLAC__StreamMetadata_VorbisComment_Entry)))) {
 991                                                         decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
 992                                                         return false;
 993                                                 }
 994                                                 for(i = 0; i < block.data.vorbis_comment.num_comments; i++) {
 995                                                         FLAC__ASSERT(FLAC__STREAM_METADATA_VORBIS_COMMENT_ENTRY_LENGTH_LEN == 32);
 996                                                         if(!FLAC__bitbuffer_read_raw_uint32_little_endian(decoder->private_->input, &block.data.vorbis_comment.comments[i].length, read_callback_, decoder))
 997                                                                 return false; /* the read_callback_ sets the state for us */
 998                                                         if(block.data.vorbis_comment.comments[i].length > 0) {
 999                                                                 if(0 == (block.data.vorbis_comment.comments[i].entry = malloc(block.data.vorbis_comment.comments[i].length))) {
1000                                                                         decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1001                                                                         return false;
1002                                                                 }
1003                                                                 if(!FLAC__bitbuffer_read_byte_block_aligned(decoder->private_->input, block.data.vorbis_comment.comments[i].entry, block.data.vorbis_comment.comments[i].length, read_callback_, decoder))
1004                                                                         return false; /* the read_callback_ sets the state for us */
1005                                                         }
1006                                                         else
1007                                                                 block.data.vorbis_comment.comments[i].entry = 0;
1008                                                 }
1009                                         }
1010                                         else {
1011                                                 block.data.vorbis_comment.comments = 0;
1012                                         }
1013                                         break;
1014                                 case FLAC__METADATA_TYPE_STREAMINFO:
1015                                 case FLAC__METADATA_TYPE_SEEKTABLE:
1016                                 default:
1017                                         FLAC__ASSERT(0);
1018                         }
1019                         decoder->private_->metadata_callback(decoder, &block, decoder->private_->client_data);
1020
1021                         /* now we have to free any malloc'ed data in the block */
1022                         switch(type) {
1023                                 case FLAC__METADATA_TYPE_PADDING:
1024                                         break;
1025                                 case FLAC__METADATA_TYPE_APPLICATION:
1026                                         if(0 != block.data.application.data)
1027                                                 free(block.data.application.data);
1028                                         break;
1029                                 case FLAC__METADATA_TYPE_VORBIS_COMMENT:
1030                                         if(0 != block.data.vorbis_comment.vendor_string.entry)
1031                                                 free(block.data.vorbis_comment.vendor_string.entry);
1032                                         if(block.data.vorbis_comment.num_comments > 0)
1033                                                 for(i = 0; i < block.data.vorbis_comment.num_comments; i++)
1034                                                         if(0 != block.data.vorbis_comment.comments[i].entry)
1035                                                                 free(block.data.vorbis_comment.comments[i].entry);
1036                                         if(0 != block.data.vorbis_comment.comments)
1037                                                 free(block.data.vorbis_comment.comments);
1038                                         break;
1039                                 case FLAC__METADATA_TYPE_STREAMINFO:
1040                                 case FLAC__METADATA_TYPE_SEEKTABLE:
1041                                 default:
1042                                         FLAC__ASSERT(0);
1043                         }
1044                 }
1045         }
1046
1047         if(last_block)
1048                 decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
1049
1050         return true;
1051 }
1052
1053 FLAC__bool skip_id3v2_tag_(FLAC__StreamDecoder *decoder)
1054 {
1055         FLAC__uint32 x;
1056         unsigned i, skip;
1057
1058         /* skip the version and flags bytes */
1059         if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &x, 24, read_callback_, decoder))
1060                 return false; /* the read_callback_ sets the state for us */
1061         /* get the size (in bytes) to skip */
1062         skip = 0;
1063         for(i = 0; i < 4; i++) {
1064                 if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &x, 8, read_callback_, decoder))
1065                         return false; /* the read_callback_ sets the state for us */
1066                 skip <<= 7;
1067                 skip |= (x & 0x7f);
1068         }
1069         /* skip the rest of the tag */
1070         if(!FLAC__bitbuffer_read_byte_block_aligned(decoder->private_->input, 0, skip, read_callback_, decoder))
1071                 return false; /* the read_callback_ sets the state for us */
1072         return true;
1073 }
1074
1075 FLAC__bool frame_sync_(FLAC__StreamDecoder *decoder)
1076 {
1077         FLAC__uint32 x;
1078         FLAC__bool first = true;
1079
1080         /* If we know the total number of samples in the stream, stop if we've read that many. */
1081         /* This will stop us, for example, from wasting time trying to sync on an ID3V1 tag. */
1082         if(decoder->private_->has_stream_info && decoder->private_->stream_info.data.stream_info.total_samples) {
1083                 if(decoder->private_->samples_decoded >= decoder->private_->stream_info.data.stream_info.total_samples) {
1084                         decoder->protected_->state = FLAC__STREAM_DECODER_END_OF_STREAM;
1085                         return true;
1086                 }
1087         }
1088
1089         /* make sure we're byte aligned */
1090         if(!FLAC__bitbuffer_is_consumed_byte_aligned(decoder->private_->input)) {
1091                 if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &x, FLAC__bitbuffer_bits_left_for_byte_alignment(decoder->private_->input), read_callback_, decoder))
1092                         return false; /* the read_callback_ sets the state for us */
1093         }
1094
1095         while(1) {
1096                 if(decoder->private_->cached) {
1097                         x = (FLAC__uint32)decoder->private_->lookahead;
1098                         decoder->private_->cached = false;
1099                 }
1100                 else {
1101                         if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &x, 8, read_callback_, decoder))
1102                                 return false; /* the read_callback_ sets the state for us */
1103                 }
1104                 if(x == 0xff) { /* MAGIC NUMBER for the first 8 frame sync bits */
1105                         decoder->private_->header_warmup[0] = (FLAC__byte)x;
1106                         if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &x, 8, read_callback_, decoder))
1107                                 return false; /* the read_callback_ sets the state for us */
1108
1109                         /* we have to check if we just read two 0xff's in a row; the second may actually be the beginning of the sync code */
1110                         /* else we have to check if the second byte is the end of a sync code */
1111                         if(x == 0xff) { /* MAGIC NUMBER for the first 8 frame sync bits */
1112                                 decoder->private_->lookahead = (FLAC__byte)x;
1113                                 decoder->private_->cached = true;
1114                         }
1115                         else if(x >> 2 == 0x3e) { /* MAGIC NUMBER for the last 6 sync bits */
1116                                 decoder->private_->header_warmup[1] = (FLAC__byte)x;
1117                                 decoder->protected_->state = FLAC__STREAM_DECODER_READ_FRAME;
1118                                 return true;
1119                         }
1120                 }
1121                 if(first) {
1122                         decoder->private_->error_callback(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC, decoder->private_->client_data);
1123                         first = false;
1124                 }
1125         }
1126
1127         return true;
1128 }
1129
1130 FLAC__bool read_frame_(FLAC__StreamDecoder *decoder, FLAC__bool *got_a_frame)
1131 {
1132         unsigned channel;
1133         unsigned i;
1134         FLAC__int32 mid, side, left, right;
1135         FLAC__uint16 frame_crc; /* the one we calculate from the input stream */
1136         FLAC__uint32 x;
1137
1138         *got_a_frame = false;
1139
1140         /* init the CRC */
1141         frame_crc = 0;
1142         FLAC__CRC16_UPDATE(decoder->private_->header_warmup[0], frame_crc);
1143         FLAC__CRC16_UPDATE(decoder->private_->header_warmup[1], frame_crc);
1144         FLAC__bitbuffer_reset_read_crc16(decoder->private_->input, frame_crc);
1145
1146         if(!read_frame_header_(decoder))
1147                 return false;
1148         if(decoder->protected_->state == FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC)
1149                 return true;
1150         if(!allocate_output_(decoder, decoder->private_->frame.header.blocksize, decoder->private_->frame.header.channels))
1151                 return false;
1152         for(channel = 0; channel < decoder->private_->frame.header.channels; channel++) {
1153                 /*
1154                  * first figure the correct bits-per-sample of the subframe
1155                  */
1156                 unsigned bps = decoder->private_->frame.header.bits_per_sample;
1157                 switch(decoder->private_->frame.header.channel_assignment) {
1158                         case FLAC__CHANNEL_ASSIGNMENT_INDEPENDENT:
1159                                 /* no adjustment needed */
1160                                 break;
1161                         case FLAC__CHANNEL_ASSIGNMENT_LEFT_SIDE:
1162                                 FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
1163                                 if(channel == 1)
1164                                         bps++;
1165                                 break;
1166                         case FLAC__CHANNEL_ASSIGNMENT_RIGHT_SIDE:
1167                                 FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
1168                                 if(channel == 0)
1169                                         bps++;
1170                                 break;
1171                         case FLAC__CHANNEL_ASSIGNMENT_MID_SIDE:
1172                                 FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
1173                                 if(channel == 1)
1174                                         bps++;
1175                                 break;
1176                         default:
1177                                 FLAC__ASSERT(0);
1178                 }
1179                 /*
1180                  * now read it
1181                  */
1182                 if(!read_subframe_(decoder, channel, bps))
1183                         return false;
1184                 if(decoder->protected_->state != FLAC__STREAM_DECODER_READ_FRAME) {
1185                         decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
1186                         return true;
1187                 }
1188         }
1189         if(!read_zero_padding_(decoder))
1190                 return false;
1191
1192         /*
1193          * Read the frame CRC-16 from the footer and check
1194          */
1195         frame_crc = FLAC__bitbuffer_get_read_crc16(decoder->private_->input);
1196         if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &x, FLAC__FRAME_FOOTER_CRC_LEN, read_callback_, decoder))
1197                 return false; /* the read_callback_ sets the state for us */
1198         if(frame_crc == (FLAC__uint16)x) {
1199                 /* Undo any special channel coding */
1200                 switch(decoder->private_->frame.header.channel_assignment) {
1201                         case FLAC__CHANNEL_ASSIGNMENT_INDEPENDENT:
1202                                 /* do nothing */
1203                                 break;
1204                         case FLAC__CHANNEL_ASSIGNMENT_LEFT_SIDE:
1205                                 FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
1206                                 for(i = 0; i < decoder->private_->frame.header.blocksize; i++)
1207                                         decoder->private_->output[1][i] = decoder->private_->output[0][i] - decoder->private_->output[1][i];
1208                                 break;
1209                         case FLAC__CHANNEL_ASSIGNMENT_RIGHT_SIDE:
1210                                 FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
1211                                 for(i = 0; i < decoder->private_->frame.header.blocksize; i++)
1212                                         decoder->private_->output[0][i] += decoder->private_->output[1][i];
1213                                 break;
1214                         case FLAC__CHANNEL_ASSIGNMENT_MID_SIDE:
1215                                 FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
1216                                 for(i = 0; i < decoder->private_->frame.header.blocksize; i++) {
1217                                         mid = decoder->private_->output[0][i];
1218                                         side = decoder->private_->output[1][i];
1219                                         mid <<= 1;
1220                                         if(side & 1) /* i.e. if 'side' is odd... */
1221                                                 mid++;
1222                                         left = mid + side;
1223                                         right = mid - side;
1224                                         decoder->private_->output[0][i] = left >> 1;
1225                                         decoder->private_->output[1][i] = right >> 1;
1226                                 }
1227                                 break;
1228                         default:
1229                                 FLAC__ASSERT(0);
1230                                 break;
1231                 }
1232         }
1233         else {
1234                 /* Bad frame, emit error and zero the output signal */
1235                 decoder->private_->error_callback(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_FRAME_CRC_MISMATCH, decoder->private_->client_data);
1236                 for(channel = 0; channel < decoder->private_->frame.header.channels; channel++) {
1237                         memset(decoder->private_->output[channel], 0, sizeof(FLAC__int32) * decoder->private_->frame.header.blocksize);
1238                 }
1239         }
1240
1241         *got_a_frame = true;
1242
1243         /* put the latest values into the public section of the decoder instance */
1244         decoder->protected_->channels = decoder->private_->frame.header.channels;
1245         decoder->protected_->channel_assignment = decoder->private_->frame.header.channel_assignment;
1246         decoder->protected_->bits_per_sample = decoder->private_->frame.header.bits_per_sample;
1247         decoder->protected_->sample_rate = decoder->private_->frame.header.sample_rate;
1248         decoder->protected_->blocksize = decoder->private_->frame.header.blocksize;
1249
1250         FLAC__ASSERT(decoder->private_->frame.header.number_type == FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER);
1251         decoder->private_->samples_decoded = decoder->private_->frame.header.number.sample_number + decoder->private_->frame.header.blocksize;
1252
1253         /* write it */
1254         if(decoder->private_->write_callback(decoder, &decoder->private_->frame, (const FLAC__int32 * const *)decoder->private_->output, decoder->private_->client_data) != FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE)
1255                 return false;
1256
1257         decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
1258         return true;
1259 }
1260
1261 FLAC__bool read_frame_header_(FLAC__StreamDecoder *decoder)
1262 {
1263         FLAC__uint32 x;
1264         FLAC__uint64 xx;
1265         unsigned i, blocksize_hint = 0, sample_rate_hint = 0;
1266         FLAC__byte crc8, raw_header[16]; /* MAGIC NUMBER based on the maximum frame header size, including CRC */
1267         unsigned raw_header_len;
1268         FLAC__bool is_unparseable = false;
1269         const FLAC__bool is_known_variable_blocksize_stream = (decoder->private_->has_stream_info && decoder->private_->stream_info.data.stream_info.min_blocksize != decoder->private_->stream_info.data.stream_info.max_blocksize);
1270         const FLAC__bool is_known_fixed_blocksize_stream = (decoder->private_->has_stream_info && decoder->private_->stream_info.data.stream_info.min_blocksize == decoder->private_->stream_info.data.stream_info.max_blocksize);
1271
1272         FLAC__ASSERT(FLAC__bitbuffer_is_consumed_byte_aligned(decoder->private_->input));
1273
1274         /* init the raw header with the saved bits from synchronization */
1275         raw_header[0] = decoder->private_->header_warmup[0];
1276         raw_header[1] = decoder->private_->header_warmup[1];
1277         raw_header_len = 2;
1278
1279         /*
1280          * check to make sure that the reserved bits are 0
1281          */
1282         if(raw_header[1] & 0x03) { /* MAGIC NUMBER */
1283                 is_unparseable = true;
1284         }
1285
1286         /*
1287          * Note that along the way as we read the header, we look for a sync
1288          * code inside.  If we find one it would indicate that our original
1289          * sync was bad since there cannot be a sync code in a valid header.
1290          */
1291
1292         /*
1293          * read in the raw header as bytes so we can CRC it, and parse it on the way
1294          */
1295         for(i = 0; i < 2; i++) {
1296                 if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &x, 8, read_callback_, decoder))
1297                         return false; /* the read_callback_ sets the state for us */
1298                 if(x == 0xff) { /* MAGIC NUMBER for the first 8 frame sync bits */
1299                         /* if we get here it means our original sync was erroneous since the sync code cannot appear in the header */
1300                         decoder->private_->lookahead = (FLAC__byte)x;
1301                         decoder->private_->cached = true;
1302                         decoder->private_->error_callback(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER, decoder->private_->client_data);
1303                         decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
1304                         return true;
1305                 }
1306                 raw_header[raw_header_len++] = (FLAC__byte)x;
1307         }
1308
1309         switch(x = raw_header[2] >> 4) {
1310                 case 0:
1311                         if(is_known_fixed_blocksize_stream)
1312                                 decoder->private_->frame.header.blocksize = decoder->private_->stream_info.data.stream_info.min_blocksize;
1313                         else
1314                                 is_unparseable = true;
1315                         break;
1316                 case 1:
1317                         decoder->private_->frame.header.blocksize = 192;
1318                         break;
1319                 case 2:
1320                 case 3:
1321                 case 4:
1322                 case 5:
1323                         decoder->private_->frame.header.blocksize = 576 << (x-2);
1324                         break;
1325                 case 6:
1326                 case 7:
1327                         blocksize_hint = x;
1328                         break;
1329                 case 8:
1330                 case 9:
1331                 case 10:
1332                 case 11:
1333                 case 12:
1334                 case 13:
1335                 case 14:
1336                 case 15:
1337                         decoder->private_->frame.header.blocksize = 256 << (x-8);
1338                         break;
1339                 default:
1340                         FLAC__ASSERT(0);
1341                         break;
1342         }
1343
1344         switch(x = raw_header[2] & 0x0f) {
1345                 case 0:
1346                         if(decoder->private_->has_stream_info)
1347                                 decoder->private_->frame.header.sample_rate = decoder->private_->stream_info.data.stream_info.sample_rate;
1348                         else
1349                                 is_unparseable = true;
1350                         break;
1351                 case 1:
1352                 case 2:
1353                 case 3:
1354                         is_unparseable = true;
1355                         break;
1356                 case 4:
1357                         decoder->private_->frame.header.sample_rate = 8000;
1358                         break;
1359                 case 5:
1360                         decoder->private_->frame.header.sample_rate = 16000;
1361                         break;
1362                 case 6:
1363                         decoder->private_->frame.header.sample_rate = 22050;
1364                         break;
1365                 case 7:
1366                         decoder->private_->frame.header.sample_rate = 24000;
1367                         break;
1368                 case 8:
1369                         decoder->private_->frame.header.sample_rate = 32000;
1370                         break;
1371                 case 9:
1372                         decoder->private_->frame.header.sample_rate = 44100;
1373                         break;
1374                 case 10:
1375                         decoder->private_->frame.header.sample_rate = 48000;
1376                         break;
1377                 case 11:
1378                         decoder->private_->frame.header.sample_rate = 96000;
1379                         break;
1380                 case 12:
1381                 case 13:
1382                 case 14:
1383                         sample_rate_hint = x;
1384                         break;
1385                 case 15:
1386                         decoder->private_->error_callback(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER, decoder->private_->client_data);
1387                         decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
1388                         return true;
1389                 default:
1390                         FLAC__ASSERT(0);
1391         }
1392
1393         x = (unsigned)(raw_header[3] >> 4);
1394         if(x & 8) {
1395                 decoder->private_->frame.header.channels = 2;
1396                 switch(x & 7) {
1397                         case 0:
1398                                 decoder->private_->frame.header.channel_assignment = FLAC__CHANNEL_ASSIGNMENT_LEFT_SIDE;
1399                                 break;
1400                         case 1:
1401                                 decoder->private_->frame.header.channel_assignment = FLAC__CHANNEL_ASSIGNMENT_RIGHT_SIDE;
1402                                 break;
1403                         case 2:
1404                                 decoder->private_->frame.header.channel_assignment = FLAC__CHANNEL_ASSIGNMENT_MID_SIDE;
1405                                 break;
1406                         default:
1407                                 is_unparseable = true;
1408                                 break;
1409                 }
1410         }
1411         else {
1412                 decoder->private_->frame.header.channels = (unsigned)x + 1;
1413                 decoder->private_->frame.header.channel_assignment = FLAC__CHANNEL_ASSIGNMENT_INDEPENDENT;
1414         }
1415
1416         switch(x = (unsigned)(raw_header[3] & 0x0e) >> 1) {
1417                 case 0:
1418                         if(decoder->private_->has_stream_info)
1419                                 decoder->private_->frame.header.bits_per_sample = decoder->private_->stream_info.data.stream_info.bits_per_sample;
1420                         else
1421                                 is_unparseable = true;
1422                         break;
1423                 case 1:
1424                         decoder->private_->frame.header.bits_per_sample = 8;
1425                         break;
1426                 case 2:
1427                         decoder->private_->frame.header.bits_per_sample = 12;
1428                         break;
1429                 case 4:
1430                         decoder->private_->frame.header.bits_per_sample = 16;
1431                         break;
1432                 case 5:
1433                         decoder->private_->frame.header.bits_per_sample = 20;
1434                         break;
1435                 case 6:
1436                         decoder->private_->frame.header.bits_per_sample = 24;
1437                         break;
1438                 case 3:
1439                 case 7:
1440                         is_unparseable = true;
1441                         break;
1442                 default:
1443                         FLAC__ASSERT(0);
1444                         break;
1445         }
1446
1447         if(raw_header[3] & 0x01) { /* this should be a zero padding bit */
1448                 decoder->private_->error_callback(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER, decoder->private_->client_data);
1449                 decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
1450                 return true;
1451         }
1452
1453         if(blocksize_hint && is_known_variable_blocksize_stream) {
1454                 if(!FLAC__bitbuffer_read_utf8_uint64(decoder->private_->input, &xx, read_callback_, decoder, raw_header, &raw_header_len))
1455                         return false; /* the read_callback_ sets the state for us */
1456                 if(xx == 0xffffffffffffffff) { /* i.e. non-UTF8 code... */
1457                         decoder->private_->lookahead = raw_header[raw_header_len-1]; /* back up as much as we can */
1458                         decoder->private_->cached = true;
1459                         decoder->private_->error_callback(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER, decoder->private_->client_data);
1460                         decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
1461                         return true;
1462                 }
1463                 decoder->private_->frame.header.number_type = FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER;
1464                 decoder->private_->frame.header.number.sample_number = xx;
1465         }
1466         else {
1467                 if(!FLAC__bitbuffer_read_utf8_uint32(decoder->private_->input, &x, read_callback_, decoder, raw_header, &raw_header_len))
1468                         return false; /* the read_callback_ sets the state for us */
1469                 if(x == 0xffffffff) { /* i.e. non-UTF8 code... */
1470                         decoder->private_->lookahead = raw_header[raw_header_len-1]; /* back up as much as we can */
1471                         decoder->private_->cached = true;
1472                         decoder->private_->error_callback(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER, decoder->private_->client_data);
1473                         decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
1474                         return true;
1475                 }
1476                 decoder->private_->last_frame_number = x;
1477                 if(decoder->private_->has_stream_info) {
1478                         decoder->private_->frame.header.number_type = FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER;
1479                         decoder->private_->frame.header.number.sample_number = (FLAC__int64)decoder->private_->stream_info.data.stream_info.min_blocksize * (FLAC__int64)x;
1480                 }
1481                 else {
1482                         is_unparseable = true;
1483                 }
1484         }
1485
1486         if(blocksize_hint) {
1487                 if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &x, 8, read_callback_, decoder))
1488                         return false; /* the read_callback_ sets the state for us */
1489                 raw_header[raw_header_len++] = (FLAC__byte)x;
1490                 if(blocksize_hint == 7) {
1491                         FLAC__uint32 _x;
1492                         if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &_x, 8, read_callback_, decoder))
1493                                 return false; /* the read_callback_ sets the state for us */
1494                         raw_header[raw_header_len++] = (FLAC__byte)_x;
1495                         x = (x << 8) | _x;
1496                 }
1497                 decoder->private_->frame.header.blocksize = x+1;
1498         }
1499
1500         if(sample_rate_hint) {
1501                 if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &x, 8, read_callback_, decoder))
1502                         return false; /* the read_callback_ sets the state for us */
1503                 raw_header[raw_header_len++] = (FLAC__byte)x;
1504                 if(sample_rate_hint != 12) {
1505                         FLAC__uint32 _x;
1506                         if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &_x, 8, read_callback_, decoder))
1507                                 return false; /* the read_callback_ sets the state for us */
1508                         raw_header[raw_header_len++] = (FLAC__byte)_x;
1509                         x = (x << 8) | _x;
1510                 }
1511                 if(sample_rate_hint == 12)
1512                         decoder->private_->frame.header.sample_rate = x*1000;
1513                 else if(sample_rate_hint == 13)
1514                         decoder->private_->frame.header.sample_rate = x;
1515                 else
1516                         decoder->private_->frame.header.sample_rate = x*10;
1517         }
1518
1519         /* read the CRC-8 byte */
1520         if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &x, 8, read_callback_, decoder))
1521                 return false; /* the read_callback_ sets the state for us */
1522         crc8 = (FLAC__byte)x;
1523
1524         if(FLAC__crc8(raw_header, raw_header_len) != crc8) {
1525                 decoder->private_->error_callback(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER, decoder->private_->client_data);
1526                 decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
1527                 return true;
1528         }
1529
1530         if(is_unparseable) {
1531                 decoder->protected_->state = FLAC__STREAM_DECODER_UNPARSEABLE_STREAM;
1532                 return false;
1533         }
1534
1535         return true;
1536 }
1537
1538 FLAC__bool read_subframe_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps)
1539 {
1540         FLAC__uint32 x;
1541         FLAC__bool wasted_bits;
1542
1543         if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &x, 8, read_callback_, decoder)) /* MAGIC NUMBER */
1544                 return false; /* the read_callback_ sets the state for us */
1545
1546         wasted_bits = (x & 1);
1547         x &= 0xfe;
1548
1549         if(wasted_bits) {
1550                 unsigned u;
1551                 if(!FLAC__bitbuffer_read_unary_unsigned(decoder->private_->input, &u, read_callback_, decoder))
1552                         return false; /* the read_callback_ sets the state for us */
1553                 decoder->private_->frame.subframes[channel].wasted_bits = u+1;
1554                 bps -= decoder->private_->frame.subframes[channel].wasted_bits;
1555         }
1556         else
1557                 decoder->private_->frame.subframes[channel].wasted_bits = 0;
1558
1559         /*
1560          * Lots of magic numbers here
1561          */
1562         if(x & 0x80) {
1563                 decoder->private_->error_callback(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC, decoder->private_->client_data);
1564                 decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
1565                 return true;
1566         }
1567         else if(x == 0) {
1568                 if(!read_subframe_constant_(decoder, channel, bps))
1569                         return false;
1570         }
1571         else if(x == 2) {
1572                 if(!read_subframe_verbatim_(decoder, channel, bps))
1573                         return false;
1574         }
1575         else if(x < 16) {
1576                 decoder->protected_->state = FLAC__STREAM_DECODER_UNPARSEABLE_STREAM;
1577                 return false;
1578         }
1579         else if(x <= 24) {
1580                 if(!read_subframe_fixed_(decoder, channel, bps, (x>>1)&7))
1581                         return false;
1582         }
1583         else if(x < 64) {
1584                 decoder->protected_->state = FLAC__STREAM_DECODER_UNPARSEABLE_STREAM;
1585                 return false;
1586         }
1587         else {
1588                 if(!read_subframe_lpc_(decoder, channel, bps, ((x>>1)&31)+1))
1589                         return false;
1590         }
1591
1592         if(wasted_bits) {
1593                 unsigned i;
1594                 x = decoder->private_->frame.subframes[channel].wasted_bits;
1595                 for(i = 0; i < decoder->private_->frame.header.blocksize; i++)
1596                         decoder->private_->output[channel][i] <<= x;
1597         }
1598
1599         return true;
1600 }
1601
1602 FLAC__bool read_subframe_constant_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps)
1603 {
1604         FLAC__Subframe_Constant *subframe = &decoder->private_->frame.subframes[channel].data.constant;
1605         FLAC__int32 x;
1606         unsigned i;
1607         FLAC__int32 *output = decoder->private_->output[channel];
1608
1609         decoder->private_->frame.subframes[channel].type = FLAC__SUBFRAME_TYPE_CONSTANT;
1610
1611         if(!FLAC__bitbuffer_read_raw_int32(decoder->private_->input, &x, bps, read_callback_, decoder))
1612                 return false; /* the read_callback_ sets the state for us */
1613
1614         subframe->value = x;
1615
1616         /* decode the subframe */
1617         for(i = 0; i < decoder->private_->frame.header.blocksize; i++)
1618                 output[i] = x;
1619
1620         return true;
1621 }
1622
1623 FLAC__bool read_subframe_fixed_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, const unsigned order)
1624 {
1625         FLAC__Subframe_Fixed *subframe = &decoder->private_->frame.subframes[channel].data.fixed;
1626         FLAC__int32 i32;
1627         FLAC__uint32 u32;
1628         unsigned u;
1629
1630         decoder->private_->frame.subframes[channel].type = FLAC__SUBFRAME_TYPE_FIXED;
1631
1632         subframe->residual = decoder->private_->residual[channel];
1633         subframe->order = order;
1634
1635         /* read warm-up samples */
1636         for(u = 0; u < order; u++) {
1637                 if(!FLAC__bitbuffer_read_raw_int32(decoder->private_->input, &i32, bps, read_callback_, decoder))
1638                         return false; /* the read_callback_ sets the state for us */
1639                 subframe->warmup[u] = i32;
1640         }
1641
1642         /* read entropy coding method info */
1643         if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &u32, FLAC__ENTROPY_CODING_METHOD_TYPE_LEN, read_callback_, decoder))
1644                 return false; /* the read_callback_ sets the state for us */
1645         subframe->entropy_coding_method.type = u32;
1646         switch(subframe->entropy_coding_method.type) {
1647                 case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE:
1648                         if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &u32, FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_ORDER_LEN, read_callback_, decoder))
1649                                 return false; /* the read_callback_ sets the state for us */
1650                         subframe->entropy_coding_method.data.partitioned_rice.order = u32;
1651                         subframe->entropy_coding_method.data.partitioned_rice.contents = &decoder->private_->partitioned_rice_contents[channel];
1652                         break;
1653                 default:
1654                         decoder->protected_->state = FLAC__STREAM_DECODER_UNPARSEABLE_STREAM;
1655                         return false;
1656         }
1657
1658         /* read residual */
1659         switch(subframe->entropy_coding_method.type) {
1660                 case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE:
1661                         if(!read_residual_partitioned_rice_(decoder, order, subframe->entropy_coding_method.data.partitioned_rice.order, &decoder->private_->partitioned_rice_contents[channel], decoder->private_->residual[channel]))
1662                                 return false;
1663                         break;
1664                 default:
1665                         FLAC__ASSERT(0);
1666         }
1667
1668         /* decode the subframe */
1669         memcpy(decoder->private_->output[channel], subframe->warmup, sizeof(FLAC__int32) * order);
1670         FLAC__fixed_restore_signal(decoder->private_->residual[channel], decoder->private_->frame.header.blocksize-order, order, decoder->private_->output[channel]+order);
1671
1672         return true;
1673 }
1674
1675 FLAC__bool read_subframe_lpc_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, const unsigned order)
1676 {
1677         FLAC__Subframe_LPC *subframe = &decoder->private_->frame.subframes[channel].data.lpc;
1678         FLAC__int32 i32;
1679         FLAC__uint32 u32;
1680         unsigned u;
1681
1682         decoder->private_->frame.subframes[channel].type = FLAC__SUBFRAME_TYPE_LPC;
1683
1684         subframe->residual = decoder->private_->residual[channel];
1685         subframe->order = order;
1686
1687         /* read warm-up samples */
1688         for(u = 0; u < order; u++) {
1689                 if(!FLAC__bitbuffer_read_raw_int32(decoder->private_->input, &i32, bps, read_callback_, decoder))
1690                         return false; /* the read_callback_ sets the state for us */
1691                 subframe->warmup[u] = i32;
1692         }
1693
1694         /* read qlp coeff precision */
1695         if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &u32, FLAC__SUBFRAME_LPC_QLP_COEFF_PRECISION_LEN, read_callback_, decoder))
1696                 return false; /* the read_callback_ sets the state for us */
1697         if(u32 == (1u << FLAC__SUBFRAME_LPC_QLP_COEFF_PRECISION_LEN) - 1) {
1698                 decoder->private_->error_callback(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC, decoder->private_->client_data);
1699                 decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
1700                 return true;
1701         }
1702         subframe->qlp_coeff_precision = u32+1;
1703
1704         /* read qlp shift */
1705         if(!FLAC__bitbuffer_read_raw_int32(decoder->private_->input, &i32, FLAC__SUBFRAME_LPC_QLP_SHIFT_LEN, read_callback_, decoder))
1706                 return false; /* the read_callback_ sets the state for us */
1707         subframe->quantization_level = i32;
1708
1709         /* read quantized lp coefficiencts */
1710         for(u = 0; u < order; u++) {
1711                 if(!FLAC__bitbuffer_read_raw_int32(decoder->private_->input, &i32, subframe->qlp_coeff_precision, read_callback_, decoder))
1712                         return false; /* the read_callback_ sets the state for us */
1713                 subframe->qlp_coeff[u] = i32;
1714         }
1715
1716         /* read entropy coding method info */
1717         if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &u32, FLAC__ENTROPY_CODING_METHOD_TYPE_LEN, read_callback_, decoder))
1718                 return false; /* the read_callback_ sets the state for us */
1719         subframe->entropy_coding_method.type = u32;
1720         switch(subframe->entropy_coding_method.type) {
1721                 case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE:
1722                         if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &u32, FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_ORDER_LEN, read_callback_, decoder))
1723                                 return false; /* the read_callback_ sets the state for us */
1724                         subframe->entropy_coding_method.data.partitioned_rice.order = u32;
1725                         subframe->entropy_coding_method.data.partitioned_rice.contents = &decoder->private_->partitioned_rice_contents[channel];
1726                         break;
1727                 default:
1728                         decoder->protected_->state = FLAC__STREAM_DECODER_UNPARSEABLE_STREAM;
1729                         return false;
1730         }
1731
1732         /* read residual */
1733         switch(subframe->entropy_coding_method.type) {
1734                 case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE:
1735                         if(!read_residual_partitioned_rice_(decoder, order, subframe->entropy_coding_method.data.partitioned_rice.order, &decoder->private_->partitioned_rice_contents[channel], decoder->private_->residual[channel]))
1736                                 return false;
1737                         break;
1738                 default:
1739                         FLAC__ASSERT(0);
1740         }
1741
1742         /* decode the subframe */
1743         memcpy(decoder->private_->output[channel], subframe->warmup, sizeof(FLAC__int32) * order);
1744         if(bps <= 16 && subframe->qlp_coeff_precision <= 16)
1745                 decoder->private_->local_lpc_restore_signal_16bit(decoder->private_->residual[channel], decoder->private_->frame.header.blocksize-order, subframe->qlp_coeff, order, subframe->quantization_level, decoder->private_->output[channel]+order);
1746         else if(bps + subframe->qlp_coeff_precision + order <= 32)
1747                 decoder->private_->local_lpc_restore_signal(decoder->private_->residual[channel], decoder->private_->frame.header.blocksize-order, subframe->qlp_coeff, order, subframe->quantization_level, decoder->private_->output[channel]+order);
1748         else
1749                 decoder->private_->local_lpc_restore_signal_64bit(decoder->private_->residual[channel], decoder->private_->frame.header.blocksize-order, subframe->qlp_coeff, order, subframe->quantization_level, decoder->private_->output[channel]+order);
1750
1751         return true;
1752 }
1753
1754 FLAC__bool read_subframe_verbatim_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps)
1755 {
1756         FLAC__Subframe_Verbatim *subframe = &decoder->private_->frame.subframes[channel].data.verbatim;
1757         FLAC__int32 x, *residual = decoder->private_->residual[channel];
1758         unsigned i;
1759
1760         decoder->private_->frame.subframes[channel].type = FLAC__SUBFRAME_TYPE_VERBATIM;
1761
1762         subframe->data = residual;
1763
1764         for(i = 0; i < decoder->private_->frame.header.blocksize; i++) {
1765                 if(!FLAC__bitbuffer_read_raw_int32(decoder->private_->input, &x, bps, read_callback_, decoder))
1766                         return false; /* the read_callback_ sets the state for us */
1767                 residual[i] = x;
1768         }
1769
1770         /* decode the subframe */
1771         memcpy(decoder->private_->output[channel], subframe->data, sizeof(FLAC__int32) * decoder->private_->frame.header.blocksize);
1772
1773         return true;
1774 }
1775
1776 FLAC__bool read_residual_partitioned_rice_(FLAC__StreamDecoder *decoder, unsigned predictor_order, unsigned partition_order, FLAC__EntropyCodingMethod_PartitionedRiceContents *partitioned_rice_contents, FLAC__int32 *residual)
1777 {
1778         FLAC__uint32 rice_parameter;
1779         int i;
1780         unsigned partition, sample, u;
1781         const unsigned partitions = 1u << partition_order;
1782         const unsigned partition_samples = partition_order > 0? decoder->private_->frame.header.blocksize >> partition_order : decoder->private_->frame.header.blocksize - predictor_order;
1783
1784         if(!FLAC__format_entropy_coding_method_partitioned_rice_contents_ensure_size(partitioned_rice_contents, max(6, partition_order))) {
1785                 decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1786                 return false;
1787         }
1788
1789         sample = 0;
1790         for(partition = 0; partition < partitions; partition++) {
1791                 if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &rice_parameter, FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_PARAMETER_LEN, read_callback_, decoder))
1792                         return false; /* the read_callback_ sets the state for us */
1793                 partitioned_rice_contents->parameters[partition] = rice_parameter;
1794                 if(rice_parameter < FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_ESCAPE_PARAMETER) {
1795 #ifdef FLAC__SYMMETRIC_RICE
1796                         for(u = (partition_order == 0 || partition > 0)? 0 : predictor_order; u < partition_samples; u++, sample++) {
1797                                 if(!FLAC__bitbuffer_read_symmetric_rice_signed(decoder->private_->input, &i, rice_parameter, read_callback_, decoder))
1798                                         return false; /* the read_callback_ sets the state for us */
1799                                 residual[sample] = i;
1800                         }
1801 #else
1802                         u = (partition_order == 0 || partition > 0)? partition_samples : partition_samples - predictor_order;
1803                         if(!FLAC__bitbuffer_read_rice_signed_block(decoder->private_->input, residual + sample, u, rice_parameter, read_callback_, decoder))
1804                                 return false; /* the read_callback_ sets the state for us */
1805                         sample += u;
1806 #endif
1807                 }
1808                 else {
1809                         if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &rice_parameter, FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_RAW_LEN, read_callback_, decoder))
1810                                 return false; /* the read_callback_ sets the state for us */
1811                         partitioned_rice_contents->raw_bits[partition] = rice_parameter;
1812                         for(u = (partition_order == 0 || partition > 0)? 0 : predictor_order; u < partition_samples; u++, sample++) {
1813                                 if(!FLAC__bitbuffer_read_raw_int32(decoder->private_->input, &i, rice_parameter, read_callback_, decoder))
1814                                         return false; /* the read_callback_ sets the state for us */
1815                                 residual[sample] = i;
1816                         }
1817                 }
1818         }
1819
1820         return true;
1821 }
1822
1823 FLAC__bool read_zero_padding_(FLAC__StreamDecoder *decoder)
1824 {
1825         if(!FLAC__bitbuffer_is_consumed_byte_aligned(decoder->private_->input)) {
1826                 FLAC__uint32 zero = 0;
1827                 if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &zero, FLAC__bitbuffer_bits_left_for_byte_alignment(decoder->private_->input), read_callback_, decoder))
1828                         return false; /* the read_callback_ sets the state for us */
1829                 if(zero != 0) {
1830                         decoder->private_->error_callback(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC, decoder->private_->client_data);
1831                         decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
1832                 }
1833         }
1834         return true;
1835 }
1836
1837 FLAC__bool read_callback_(FLAC__byte buffer[], unsigned *bytes, void *client_data)
1838 {
1839         FLAC__StreamDecoder *decoder = (FLAC__StreamDecoder *)client_data;
1840         FLAC__StreamDecoderReadStatus status;
1841
1842         status = decoder->private_->read_callback(decoder, buffer, bytes, decoder->private_->client_data);
1843         if(status == FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM)
1844                 decoder->protected_->state = FLAC__STREAM_DECODER_END_OF_STREAM;
1845         else if(status == FLAC__STREAM_DECODER_READ_STATUS_ABORT)
1846                 decoder->protected_->state = FLAC__STREAM_DECODER_ABORTED;
1847         return status == FLAC__STREAM_DECODER_READ_STATUS_CONTINUE;
1848 }