src/libFLAC/stream_decoder.c

   1 /* libFLAC - Free Lossless Audio Codec library
   2  * Copyright (C) 2000,2001,2002,2003,2004,2005,2006,2007,2008,2009  Josh Coalson
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  *
   8  * - Redistributions of source code must retain the above copyright
   9  * notice, this list of conditions and the following disclaimer.
  10  *
  11  * - Redistributions in binary form must reproduce the above copyright
  12  * notice, this list of conditions and the following disclaimer in the
  13  * documentation and/or other materials provided with the distribution.
  14  *
  15  * - Neither the name of the Xiph.org Foundation nor the names of its
  16  * contributors may be used to endorse or promote products derived from
  17  * this software without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  21  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  22  * A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR
  23  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  24  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  25  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  26  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  27  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  28  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  29  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  30  */
  31
  32 #if HAVE_CONFIG_H
  33 #  include <config.h>
  34 #endif
  35
  36 #include <stdio.h>
  37 #include <stdlib.h> /* for malloc() */
  38 #include <string.h> /* for memset/memcpy() */
  39 #include <sys/stat.h> /* for stat() */
  40 #include <sys/types.h> /* for off_t */
  41 #include "share/compat.h"
  42 #include "FLAC/assert.h"
  43 #include "share/alloc.h"
  44 #include "protected/stream_decoder.h"
  45 #include "private/bitreader.h"
  46 #include "private/bitmath.h"
  47 #include "private/cpu.h"
  48 #include "private/crc.h"
  49 #include "private/fixed.h"
  50 #include "private/format.h"
  51 #include "private/lpc.h"
  52 #include "private/md5.h"
  53 #include "private/memory.h"
  54 #include "private/macros.h"
  55
  56
  57 /* technically this should be in an "export.c" but this is convenient enough */
  58 FLAC_API int FLAC_API_SUPPORTS_OGG_FLAC =
  59 #if FLAC__HAS_OGG
  60         1
  61 #else
  62         0
  63 #endif
  64 ;
  65
  66
  67 /***********************************************************************
  68  *
  69  * Private static data
  70  *
  71  ***********************************************************************/
  72
  73 static FLAC__byte ID3V2_TAG_[3] = { 'I', 'D', '3' };
  74
  75 /***********************************************************************
  76  *
  77  * Private class method prototypes
  78  *
  79  ***********************************************************************/
  80
  81 static void set_defaults_(FLAC__StreamDecoder *decoder);
  82 static FILE *get_binary_stdin_(void);
  83 static FLAC__bool allocate_output_(FLAC__StreamDecoder *decoder, unsigned size, unsigned channels);
  84 static FLAC__bool has_id_filtered_(FLAC__StreamDecoder *decoder, FLAC__byte *id);
  85 static FLAC__bool find_metadata_(FLAC__StreamDecoder *decoder);
  86 static FLAC__bool read_metadata_(FLAC__StreamDecoder *decoder);
  87 static FLAC__bool read_metadata_streaminfo_(FLAC__StreamDecoder *decoder, FLAC__bool is_last, unsigned length);
  88 static FLAC__bool read_metadata_seektable_(FLAC__StreamDecoder *decoder, FLAC__bool is_last, unsigned length);
  89 static FLAC__bool read_metadata_vorbiscomment_(FLAC__StreamDecoder *decoder, FLAC__StreamMetadata_VorbisComment *obj);
  90 static FLAC__bool read_metadata_cuesheet_(FLAC__StreamDecoder *decoder, FLAC__StreamMetadata_CueSheet *obj);
  91 static FLAC__bool read_metadata_picture_(FLAC__StreamDecoder *decoder, FLAC__StreamMetadata_Picture *obj);
  92 static FLAC__bool skip_id3v2_tag_(FLAC__StreamDecoder *decoder);
  93 static FLAC__bool frame_sync_(FLAC__StreamDecoder *decoder);
  94 static FLAC__bool read_frame_(FLAC__StreamDecoder *decoder, FLAC__bool *got_a_frame, FLAC__bool do_full_decode);
  95 static FLAC__bool read_frame_header_(FLAC__StreamDecoder *decoder);
  96 static FLAC__bool read_subframe_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, FLAC__bool do_full_decode);
  97 static FLAC__bool read_subframe_constant_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, FLAC__bool do_full_decode);
  98 static FLAC__bool read_subframe_fixed_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, const unsigned order, FLAC__bool do_full_decode);
  99 static FLAC__bool read_subframe_lpc_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, const unsigned order, FLAC__bool do_full_decode);
 100 static FLAC__bool read_subframe_verbatim_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, FLAC__bool do_full_decode);
 101 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, FLAC__bool is_extended);
 102 static FLAC__bool read_zero_padding_(FLAC__StreamDecoder *decoder);
 103 static FLAC__bool read_callback_(FLAC__byte buffer[], size_t *bytes, void *client_data);
 104 #if FLAC__HAS_OGG
 105 static FLAC__StreamDecoderReadStatus read_callback_ogg_aspect_(const FLAC__StreamDecoder *decoder, FLAC__byte buffer[], size_t *bytes);
 106 static FLAC__OggDecoderAspectReadStatus read_callback_proxy_(const void *void_decoder, FLAC__byte buffer[], size_t *bytes, void *client_data);
 107 #endif
 108 static FLAC__StreamDecoderWriteStatus write_audio_frame_to_client_(FLAC__StreamDecoder *decoder, const FLAC__Frame *frame, const FLAC__int32 * const buffer[]);
 109 static void send_error_to_client_(const FLAC__StreamDecoder *decoder, FLAC__StreamDecoderErrorStatus status);
 110 static FLAC__bool seek_to_absolute_sample_(FLAC__StreamDecoder *decoder, FLAC__uint64 stream_length, FLAC__uint64 target_sample);
 111 #if FLAC__HAS_OGG
 112 static FLAC__bool seek_to_absolute_sample_ogg_(FLAC__StreamDecoder *decoder, FLAC__uint64 stream_length, FLAC__uint64 target_sample);
 113 #endif
 114 static FLAC__StreamDecoderReadStatus file_read_callback_(const FLAC__StreamDecoder *decoder, FLAC__byte buffer[], size_t *bytes, void *client_data);
 115 static FLAC__StreamDecoderSeekStatus file_seek_callback_(const FLAC__StreamDecoder *decoder, FLAC__uint64 absolute_byte_offset, void *client_data);
 116 static FLAC__StreamDecoderTellStatus file_tell_callback_(const FLAC__StreamDecoder *decoder, FLAC__uint64 *absolute_byte_offset, void *client_data);
 117 static FLAC__StreamDecoderLengthStatus file_length_callback_(const FLAC__StreamDecoder *decoder, FLAC__uint64 *stream_length, void *client_data);
 118 static FLAC__bool file_eof_callback_(const FLAC__StreamDecoder *decoder, void *client_data);
 119
 120 /***********************************************************************
 121  *
 122  * Private class data
 123  *
 124  ***********************************************************************/
 125
 126 typedef struct FLAC__StreamDecoderPrivate {
 127 #if FLAC__HAS_OGG
 128         FLAC__bool is_ogg;
 129 #endif
 130         FLAC__StreamDecoderReadCallback read_callback;
 131         FLAC__StreamDecoderSeekCallback seek_callback;
 132         FLAC__StreamDecoderTellCallback tell_callback;
 133         FLAC__StreamDecoderLengthCallback length_callback;
 134         FLAC__StreamDecoderEofCallback eof_callback;
 135         FLAC__StreamDecoderWriteCallback write_callback;
 136         FLAC__StreamDecoderMetadataCallback metadata_callback;
 137         FLAC__StreamDecoderErrorCallback error_callback;
 138         /* generic 32-bit datapath: */
 139         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[]);
 140         /* generic 64-bit datapath: */
 141         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[]);
 142         /* for use when the signal is <= 16 bits-per-sample, or <= 15 bits-per-sample on a side channel (which requires 1 extra bit): */
 143         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[]);
 144         /* for use when the signal is <= 16 bits-per-sample, or <= 15 bits-per-sample on a side channel (which requires 1 extra bit), AND order <= 8: */
 145         void (*local_lpc_restore_signal_16bit_order8)(const FLAC__int32 residual[], unsigned data_len, const FLAC__int32 qlp_coeff[], unsigned order, int lp_quantization, FLAC__int32 data[]);
 146         FLAC__bool (*local_bitreader_read_rice_signed_block)(FLAC__BitReader *br, int vals[], unsigned nvals, unsigned parameter);
 147         void *client_data;
 148         FILE *file; /* only used if FLAC__stream_decoder_init_file()/FLAC__stream_decoder_init_file() called, else NULL */
 149         FLAC__BitReader *input;
 150         FLAC__int32 *output[FLAC__MAX_CHANNELS];
 151         FLAC__int32 *residual[FLAC__MAX_CHANNELS]; /* WATCHOUT: these are the aligned pointers; the real pointers that should be free()'d are residual_unaligned[] below */
 152         FLAC__EntropyCodingMethod_PartitionedRiceContents partitioned_rice_contents[FLAC__MAX_CHANNELS];
 153         unsigned output_capacity, output_channels;
 154         FLAC__uint32 fixed_block_size, next_fixed_block_size;
 155         FLAC__uint64 samples_decoded;
 156         FLAC__bool has_stream_info, has_seek_table;
 157         FLAC__StreamMetadata stream_info;
 158         FLAC__StreamMetadata seek_table;
 159         FLAC__bool metadata_filter[128]; /* MAGIC number 128 == total number of metadata block types == 1 << 7 */
 160         FLAC__byte *metadata_filter_ids;
 161         size_t metadata_filter_ids_count, metadata_filter_ids_capacity; /* units for both are IDs, not bytes */
 162         FLAC__Frame frame;
 163         FLAC__bool cached; /* true if there is a byte in lookahead */
 164         FLAC__CPUInfo cpuinfo;
 165         FLAC__byte header_warmup[2]; /* contains the sync code and reserved bits */
 166         FLAC__byte lookahead; /* temp storage when we need to look ahead one byte in the stream */
 167         /* unaligned (original) pointers to allocated data */
 168         FLAC__int32 *residual_unaligned[FLAC__MAX_CHANNELS];
 169         FLAC__bool do_md5_checking; /* initially gets protected_->md5_checking but is turned off after a seek or if the metadata has a zero MD5 */
 170         FLAC__bool internal_reset_hack; /* used only during init() so we can call reset to set up the decoder without rewinding the input */
 171         FLAC__bool is_seeking;
 172         FLAC__MD5Context md5context;
 173         FLAC__byte computed_md5sum[16]; /* this is the sum we computed from the decoded data */
 174         /* (the rest of these are only used for seeking) */
 175         FLAC__Frame last_frame; /* holds the info of the last frame we seeked to */
 176         FLAC__uint64 first_frame_offset; /* hint to the seek routine of where in the stream the first audio frame starts */
 177         FLAC__uint64 target_sample;
 178         unsigned unparseable_frame_count; /* used to tell whether we're decoding a future version of FLAC or just got a bad sync */
 179 #if FLAC__HAS_OGG
 180         FLAC__bool got_a_frame; /* hack needed in Ogg FLAC seek routine to check when process_single() actually writes a frame */
 181 #endif
 182 } FLAC__StreamDecoderPrivate;
 183
 184 /***********************************************************************
 185  *
 186  * Public static class data
 187  *
 188  ***********************************************************************/
 189
 190 FLAC_API const char * const FLAC__StreamDecoderStateString[] = {
 191         "FLAC__STREAM_DECODER_SEARCH_FOR_METADATA",
 192         "FLAC__STREAM_DECODER_READ_METADATA",
 193         "FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC",
 194         "FLAC__STREAM_DECODER_READ_FRAME",
 195         "FLAC__STREAM_DECODER_END_OF_STREAM",
 196         "FLAC__STREAM_DECODER_OGG_ERROR",
 197         "FLAC__STREAM_DECODER_SEEK_ERROR",
 198         "FLAC__STREAM_DECODER_ABORTED",
 199         "FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR",
 200         "FLAC__STREAM_DECODER_UNINITIALIZED"
 201 };
 202
 203 FLAC_API const char * const FLAC__StreamDecoderInitStatusString[] = {
 204         "FLAC__STREAM_DECODER_INIT_STATUS_OK",
 205         "FLAC__STREAM_DECODER_INIT_STATUS_UNSUPPORTED_CONTAINER",
 206         "FLAC__STREAM_DECODER_INIT_STATUS_INVALID_CALLBACKS",
 207         "FLAC__STREAM_DECODER_INIT_STATUS_MEMORY_ALLOCATION_ERROR",
 208         "FLAC__STREAM_DECODER_INIT_STATUS_ERROR_OPENING_FILE",
 209         "FLAC__STREAM_DECODER_INIT_STATUS_ALREADY_INITIALIZED"
 210 };
 211
 212 FLAC_API const char * const FLAC__StreamDecoderReadStatusString[] = {
 213         "FLAC__STREAM_DECODER_READ_STATUS_CONTINUE",
 214         "FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM",
 215         "FLAC__STREAM_DECODER_READ_STATUS_ABORT"
 216 };
 217
 218 FLAC_API const char * const FLAC__StreamDecoderSeekStatusString[] = {
 219         "FLAC__STREAM_DECODER_SEEK_STATUS_OK",
 220         "FLAC__STREAM_DECODER_SEEK_STATUS_ERROR",
 221         "FLAC__STREAM_DECODER_SEEK_STATUS_UNSUPPORTED"
 222 };
 223
 224 FLAC_API const char * const FLAC__StreamDecoderTellStatusString[] = {
 225         "FLAC__STREAM_DECODER_TELL_STATUS_OK",
 226         "FLAC__STREAM_DECODER_TELL_STATUS_ERROR",
 227         "FLAC__STREAM_DECODER_TELL_STATUS_UNSUPPORTED"
 228 };
 229
 230 FLAC_API const char * const FLAC__StreamDecoderLengthStatusString[] = {
 231         "FLAC__STREAM_DECODER_LENGTH_STATUS_OK",
 232         "FLAC__STREAM_DECODER_LENGTH_STATUS_ERROR",
 233         "FLAC__STREAM_DECODER_LENGTH_STATUS_UNSUPPORTED"
 234 };
 235
 236 FLAC_API const char * const FLAC__StreamDecoderWriteStatusString[] = {
 237         "FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE",
 238         "FLAC__STREAM_DECODER_WRITE_STATUS_ABORT"
 239 };
 240
 241 FLAC_API const char * const FLAC__StreamDecoderErrorStatusString[] = {
 242         "FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC",
 243         "FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER",
 244         "FLAC__STREAM_DECODER_ERROR_STATUS_FRAME_CRC_MISMATCH",
 245         "FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM"
 246 };
 247
 248 /***********************************************************************
 249  *
 250  * Class constructor/destructor
 251  *
 252  ***********************************************************************/
 253 FLAC_API FLAC__StreamDecoder *FLAC__stream_decoder_new(void)
 254 {
 255         FLAC__StreamDecoder *decoder;
 256         unsigned i;
 257
 258         FLAC__ASSERT(sizeof(int) >= 4); /* we want to die right away if this is not true */
 259
 260         decoder = calloc(1, sizeof(FLAC__StreamDecoder));
 261         if(decoder == 0) {
 262                 return 0;
 263         }
 264
 265         decoder->protected_ = calloc(1, sizeof(FLAC__StreamDecoderProtected));
 266         if(decoder->protected_ == 0) {
 267                 free(decoder);
 268                 return 0;
 269         }
 270
 271         decoder->private_ = calloc(1, sizeof(FLAC__StreamDecoderPrivate));
 272         if(decoder->private_ == 0) {
 273                 free(decoder->protected_);
 274                 free(decoder);
 275                 return 0;
 276         }
 277
 278         decoder->private_->input = FLAC__bitreader_new();
 279         if(decoder->private_->input == 0) {
 280                 free(decoder->private_);
 281                 free(decoder->protected_);
 282                 free(decoder);
 283                 return 0;
 284         }
 285
 286         decoder->private_->metadata_filter_ids_capacity = 16;
 287         if(0 == (decoder->private_->metadata_filter_ids = malloc((FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8) * decoder->private_->metadata_filter_ids_capacity))) {
 288                 FLAC__bitreader_delete(decoder->private_->input);
 289                 free(decoder->private_);
 290                 free(decoder->protected_);
 291                 free(decoder);
 292                 return 0;
 293         }
 294
 295         for(i = 0; i < FLAC__MAX_CHANNELS; i++) {
 296                 decoder->private_->output[i] = 0;
 297                 decoder->private_->residual_unaligned[i] = decoder->private_->residual[i] = 0;
 298         }
 299
 300         decoder->private_->output_capacity = 0;
 301         decoder->private_->output_channels = 0;
 302         decoder->private_->has_seek_table = false;
 303
 304         for(i = 0; i < FLAC__MAX_CHANNELS; i++)
 305                 FLAC__format_entropy_coding_method_partitioned_rice_contents_init(&decoder->private_->partitioned_rice_contents[i]);
 306
 307         decoder->private_->file = 0;
 308
 309         set_defaults_(decoder);
 310
 311         decoder->protected_->state = FLAC__STREAM_DECODER_UNINITIALIZED;
 312
 313         return decoder;
 314 }
 315
 316 FLAC_API void FLAC__stream_decoder_delete(FLAC__StreamDecoder *decoder)
 317 {
 318         unsigned i;
 319
 320         if (decoder == NULL)
 321                 return ;
 322
 323         FLAC__ASSERT(0 != decoder->protected_);
 324         FLAC__ASSERT(0 != decoder->private_);
 325         FLAC__ASSERT(0 != decoder->private_->input);
 326
 327         (void)FLAC__stream_decoder_finish(decoder);
 328
 329         if(0 != decoder->private_->metadata_filter_ids)
 330                 free(decoder->private_->metadata_filter_ids);
 331
 332         FLAC__bitreader_delete(decoder->private_->input);
 333
 334         for(i = 0; i < FLAC__MAX_CHANNELS; i++)
 335                 FLAC__format_entropy_coding_method_partitioned_rice_contents_clear(&decoder->private_->partitioned_rice_contents[i]);
 336
 337         free(decoder->private_);
 338         free(decoder->protected_);
 339         free(decoder);
 340 }
 341
 342 /***********************************************************************
 343  *
 344  * Public class methods
 345  *
 346  ***********************************************************************/
 347
 348 static FLAC__StreamDecoderInitStatus init_stream_internal_(
 349         FLAC__StreamDecoder *decoder,
 350         FLAC__StreamDecoderReadCallback read_callback,
 351         FLAC__StreamDecoderSeekCallback seek_callback,
 352         FLAC__StreamDecoderTellCallback tell_callback,
 353         FLAC__StreamDecoderLengthCallback length_callback,
 354         FLAC__StreamDecoderEofCallback eof_callback,
 355         FLAC__StreamDecoderWriteCallback write_callback,
 356         FLAC__StreamDecoderMetadataCallback metadata_callback,
 357         FLAC__StreamDecoderErrorCallback error_callback,
 358         void *client_data,
 359         FLAC__bool is_ogg
 360 )
 361 {
 362         FLAC__ASSERT(0 != decoder);
 363
 364         if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
 365                 return FLAC__STREAM_DECODER_INIT_STATUS_ALREADY_INITIALIZED;
 366
 367 #if !FLAC__HAS_OGG
 368         if(is_ogg)
 369                 return FLAC__STREAM_DECODER_INIT_STATUS_UNSUPPORTED_CONTAINER;
 370 #endif
 371
 372         if(
 373                 0 == read_callback ||
 374                 0 == write_callback ||
 375                 0 == error_callback ||
 376                 (seek_callback && (0 == tell_callback || 0 == length_callback || 0 == eof_callback))
 377         )
 378                 return FLAC__STREAM_DECODER_INIT_STATUS_INVALID_CALLBACKS;
 379
 380 #if FLAC__HAS_OGG
 381         decoder->private_->is_ogg = is_ogg;
 382         if(is_ogg && !FLAC__ogg_decoder_aspect_init(&decoder->protected_->ogg_decoder_aspect))
 383                 return decoder->protected_->state = FLAC__STREAM_DECODER_OGG_ERROR;
 384 #endif
 385
 386         /*
 387          * get the CPU info and set the function pointers
 388          */
 389         FLAC__cpu_info(&decoder->private_->cpuinfo);
 390         /* first default to the non-asm routines */
 391         decoder->private_->local_lpc_restore_signal = FLAC__lpc_restore_signal;
 392         decoder->private_->local_lpc_restore_signal_64bit = FLAC__lpc_restore_signal_wide;
 393         decoder->private_->local_lpc_restore_signal_16bit = FLAC__lpc_restore_signal;
 394         decoder->private_->local_lpc_restore_signal_16bit_order8 = FLAC__lpc_restore_signal;
 395         decoder->private_->local_bitreader_read_rice_signed_block = FLAC__bitreader_read_rice_signed_block;
 396         /* now override with asm where appropriate */
 397 #ifndef FLAC__NO_ASM
 398         if(decoder->private_->cpuinfo.use_asm) {
 399 #ifdef FLAC__CPU_IA32
 400                 FLAC__ASSERT(decoder->private_->cpuinfo.type == FLAC__CPUINFO_TYPE_IA32);
 401 #ifdef FLAC__HAS_NASM
 402 #if 1 /*@@@@@@ OPT: not clearly faster, needs more testing */
 403                 if(decoder->private_->cpuinfo.data.ia32.bswap)
 404                         decoder->private_->local_bitreader_read_rice_signed_block = FLAC__bitreader_read_rice_signed_block_asm_ia32_bswap;
 405 #endif
 406                 if(decoder->private_->cpuinfo.data.ia32.mmx) {
 407                         decoder->private_->local_lpc_restore_signal = FLAC__lpc_restore_signal_asm_ia32;
 408                         decoder->private_->local_lpc_restore_signal_16bit = FLAC__lpc_restore_signal_asm_ia32_mmx;
 409                         decoder->private_->local_lpc_restore_signal_16bit_order8 = FLAC__lpc_restore_signal_asm_ia32_mmx;
 410                 }
 411                 else {
 412                         decoder->private_->local_lpc_restore_signal = FLAC__lpc_restore_signal_asm_ia32;
 413                         decoder->private_->local_lpc_restore_signal_16bit = FLAC__lpc_restore_signal_asm_ia32;
 414                         decoder->private_->local_lpc_restore_signal_16bit_order8 = FLAC__lpc_restore_signal_asm_ia32;
 415                 }
 416 #endif
 417 #elif defined FLAC__CPU_PPC
 418                 FLAC__ASSERT(decoder->private_->cpuinfo.type == FLAC__CPUINFO_TYPE_PPC);
 419                 if(decoder->private_->cpuinfo.data.ppc.altivec) {
 420                         decoder->private_->local_lpc_restore_signal_16bit = FLAC__lpc_restore_signal_asm_ppc_altivec_16;
 421                         decoder->private_->local_lpc_restore_signal_16bit_order8 = FLAC__lpc_restore_signal_asm_ppc_altivec_16_order8;
 422                 }
 423 #endif
 424         }
 425 #endif
 426
 427         /* from here on, errors are fatal */
 428
 429         if(!FLAC__bitreader_init(decoder->private_->input, decoder->private_->cpuinfo, read_callback_, decoder)) {
 430                 decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
 431                 return FLAC__STREAM_DECODER_INIT_STATUS_MEMORY_ALLOCATION_ERROR;
 432         }
 433
 434         decoder->private_->read_callback = read_callback;
 435         decoder->private_->seek_callback = seek_callback;
 436         decoder->private_->tell_callback = tell_callback;
 437         decoder->private_->length_callback = length_callback;
 438         decoder->private_->eof_callback = eof_callback;
 439         decoder->private_->write_callback = write_callback;
 440         decoder->private_->metadata_callback = metadata_callback;
 441         decoder->private_->error_callback = error_callback;
 442         decoder->private_->client_data = client_data;
 443         decoder->private_->fixed_block_size = decoder->private_->next_fixed_block_size = 0;
 444         decoder->private_->samples_decoded = 0;
 445         decoder->private_->has_stream_info = false;
 446         decoder->private_->cached = false;
 447
 448         decoder->private_->do_md5_checking = decoder->protected_->md5_checking;
 449         decoder->private_->is_seeking = false;
 450
 451         decoder->private_->internal_reset_hack = true; /* so the following reset does not try to rewind the input */
 452         if(!FLAC__stream_decoder_reset(decoder)) {
 453                 /* above call sets the state for us */
 454                 return FLAC__STREAM_DECODER_INIT_STATUS_MEMORY_ALLOCATION_ERROR;
 455         }
 456
 457         return FLAC__STREAM_DECODER_INIT_STATUS_OK;
 458 }
 459
 460 FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_stream(
 461         FLAC__StreamDecoder *decoder,
 462         FLAC__StreamDecoderReadCallback read_callback,
 463         FLAC__StreamDecoderSeekCallback seek_callback,
 464         FLAC__StreamDecoderTellCallback tell_callback,
 465         FLAC__StreamDecoderLengthCallback length_callback,
 466         FLAC__StreamDecoderEofCallback eof_callback,
 467         FLAC__StreamDecoderWriteCallback write_callback,
 468         FLAC__StreamDecoderMetadataCallback metadata_callback,
 469         FLAC__StreamDecoderErrorCallback error_callback,
 470         void *client_data
 471 )
 472 {
 473         return init_stream_internal_(
 474                 decoder,
 475                 read_callback,
 476                 seek_callback,
 477                 tell_callback,
 478                 length_callback,
 479                 eof_callback,
 480                 write_callback,
 481                 metadata_callback,
 482                 error_callback,
 483                 client_data,
 484                 /*is_ogg=*/false
 485         );
 486 }
 487
 488 FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_ogg_stream(
 489         FLAC__StreamDecoder *decoder,
 490         FLAC__StreamDecoderReadCallback read_callback,
 491         FLAC__StreamDecoderSeekCallback seek_callback,
 492         FLAC__StreamDecoderTellCallback tell_callback,
 493         FLAC__StreamDecoderLengthCallback length_callback,
 494         FLAC__StreamDecoderEofCallback eof_callback,
 495         FLAC__StreamDecoderWriteCallback write_callback,
 496         FLAC__StreamDecoderMetadataCallback metadata_callback,
 497         FLAC__StreamDecoderErrorCallback error_callback,
 498         void *client_data
 499 )
 500 {
 501         return init_stream_internal_(
 502                 decoder,
 503                 read_callback,
 504                 seek_callback,
 505                 tell_callback,
 506                 length_callback,
 507                 eof_callback,
 508                 write_callback,
 509                 metadata_callback,
 510                 error_callback,
 511                 client_data,
 512                 /*is_ogg=*/true
 513         );
 514 }
 515
 516 static FLAC__StreamDecoderInitStatus init_FILE_internal_(
 517         FLAC__StreamDecoder *decoder,
 518         FILE *file,
 519         FLAC__StreamDecoderWriteCallback write_callback,
 520         FLAC__StreamDecoderMetadataCallback metadata_callback,
 521         FLAC__StreamDecoderErrorCallback error_callback,
 522         void *client_data,
 523         FLAC__bool is_ogg
 524 )
 525 {
 526         FLAC__ASSERT(0 != decoder);
 527         FLAC__ASSERT(0 != file);
 528
 529         if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
 530                 return decoder->protected_->state = FLAC__STREAM_DECODER_INIT_STATUS_ALREADY_INITIALIZED;
 531
 532         if(0 == write_callback || 0 == error_callback)
 533                 return decoder->protected_->state = FLAC__STREAM_DECODER_INIT_STATUS_INVALID_CALLBACKS;
 534
 535         /*
 536          * To make sure that our file does not go unclosed after an error, we
 537          * must assign the FILE pointer before any further error can occur in
 538          * this routine.
 539          */
 540         if(file == stdin)
 541                 file = get_binary_stdin_(); /* just to be safe */
 542
 543         decoder->private_->file = file;
 544
 545         return init_stream_internal_(
 546                 decoder,
 547                 file_read_callback_,
 548                 decoder->private_->file == stdin? 0: file_seek_callback_,
 549                 decoder->private_->file == stdin? 0: file_tell_callback_,
 550                 decoder->private_->file == stdin? 0: file_length_callback_,
 551                 file_eof_callback_,
 552                 write_callback,
 553                 metadata_callback,
 554                 error_callback,
 555                 client_data,
 556                 is_ogg
 557         );
 558 }
 559
 560 FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_FILE(
 561         FLAC__StreamDecoder *decoder,
 562         FILE *file,
 563         FLAC__StreamDecoderWriteCallback write_callback,
 564         FLAC__StreamDecoderMetadataCallback metadata_callback,
 565         FLAC__StreamDecoderErrorCallback error_callback,
 566         void *client_data
 567 )
 568 {
 569         return init_FILE_internal_(decoder, file, write_callback, metadata_callback, error_callback, client_data, /*is_ogg=*/false);
 570 }
 571
 572 FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_ogg_FILE(
 573         FLAC__StreamDecoder *decoder,
 574         FILE *file,
 575         FLAC__StreamDecoderWriteCallback write_callback,
 576         FLAC__StreamDecoderMetadataCallback metadata_callback,
 577         FLAC__StreamDecoderErrorCallback error_callback,
 578         void *client_data
 579 )
 580 {
 581         return init_FILE_internal_(decoder, file, write_callback, metadata_callback, error_callback, client_data, /*is_ogg=*/true);
 582 }
 583
 584 static FLAC__StreamDecoderInitStatus init_file_internal_(
 585         FLAC__StreamDecoder *decoder,
 586         const char *filename,
 587         FLAC__StreamDecoderWriteCallback write_callback,
 588         FLAC__StreamDecoderMetadataCallback metadata_callback,
 589         FLAC__StreamDecoderErrorCallback error_callback,
 590         void *client_data,
 591         FLAC__bool is_ogg
 592 )
 593 {
 594         FILE *file;
 595
 596         FLAC__ASSERT(0 != decoder);
 597
 598         /*
 599          * To make sure that our file does not go unclosed after an error, we
 600          * have to do the same entrance checks here that are later performed
 601          * in FLAC__stream_decoder_init_FILE() before the FILE* is assigned.
 602          */
 603         if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
 604                 return decoder->protected_->state = FLAC__STREAM_DECODER_INIT_STATUS_ALREADY_INITIALIZED;
 605
 606         if(0 == write_callback || 0 == error_callback)
 607                 return decoder->protected_->state = FLAC__STREAM_DECODER_INIT_STATUS_INVALID_CALLBACKS;
 608
 609         file = filename? flac_fopen(filename, "rb") : stdin;
 610
 611         if(0 == file)
 612                 return FLAC__STREAM_DECODER_INIT_STATUS_ERROR_OPENING_FILE;
 613
 614         return init_FILE_internal_(decoder, file, write_callback, metadata_callback, error_callback, client_data, is_ogg);
 615 }
 616
 617 FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_file(
 618         FLAC__StreamDecoder *decoder,
 619         const char *filename,
 620         FLAC__StreamDecoderWriteCallback write_callback,
 621         FLAC__StreamDecoderMetadataCallback metadata_callback,
 622         FLAC__StreamDecoderErrorCallback error_callback,
 623         void *client_data
 624 )
 625 {
 626         return init_file_internal_(decoder, filename, write_callback, metadata_callback, error_callback, client_data, /*is_ogg=*/false);
 627 }
 628
 629 FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_ogg_file(
 630         FLAC__StreamDecoder *decoder,
 631         const char *filename,
 632         FLAC__StreamDecoderWriteCallback write_callback,
 633         FLAC__StreamDecoderMetadataCallback metadata_callback,
 634         FLAC__StreamDecoderErrorCallback error_callback,
 635         void *client_data
 636 )
 637 {
 638         return init_file_internal_(decoder, filename, write_callback, metadata_callback, error_callback, client_data, /*is_ogg=*/true);
 639 }
 640
 641 FLAC_API FLAC__bool FLAC__stream_decoder_finish(FLAC__StreamDecoder *decoder)
 642 {
 643         FLAC__bool md5_failed = false;
 644         unsigned i;
 645
 646         FLAC__ASSERT(0 != decoder);
 647         FLAC__ASSERT(0 != decoder->private_);
 648         FLAC__ASSERT(0 != decoder->protected_);
 649
 650         if(decoder->protected_->state == FLAC__STREAM_DECODER_UNINITIALIZED)
 651                 return true;
 652
 653         /* see the comment in FLAC__seekable_stream_decoder_reset() as to why we
 654          * always call FLAC__MD5Final()
 655          */
 656         FLAC__MD5Final(decoder->private_->computed_md5sum, &decoder->private_->md5context);
 657
 658         if(decoder->private_->has_seek_table && 0 != decoder->private_->seek_table.data.seek_table.points) {
 659                 free(decoder->private_->seek_table.data.seek_table.points);
 660                 decoder->private_->seek_table.data.seek_table.points = 0;
 661                 decoder->private_->has_seek_table = false;
 662         }
 663         FLAC__bitreader_free(decoder->private_->input);
 664         for(i = 0; i < FLAC__MAX_CHANNELS; i++) {
 665                 /* WATCHOUT:
 666                  * FLAC__lpc_restore_signal_asm_ia32_mmx() requires that the
 667                  * output arrays have a buffer of up to 3 zeroes in front
 668                  * (at negative indices) for alignment purposes; we use 4
 669                  * to keep the data well-aligned.
 670                  */
 671                 if(0 != decoder->private_->output[i]) {
 672                         free(decoder->private_->output[i]-4);
 673                         decoder->private_->output[i] = 0;
 674                 }
 675                 if(0 != decoder->private_->residual_unaligned[i]) {
 676                         free(decoder->private_->residual_unaligned[i]);
 677                         decoder->private_->residual_unaligned[i] = decoder->private_->residual[i] = 0;
 678                 }
 679         }
 680         decoder->private_->output_capacity = 0;
 681         decoder->private_->output_channels = 0;
 682
 683 #if FLAC__HAS_OGG
 684         if(decoder->private_->is_ogg)
 685                 FLAC__ogg_decoder_aspect_finish(&decoder->protected_->ogg_decoder_aspect);
 686 #endif
 687
 688         if(0 != decoder->private_->file) {
 689                 if(decoder->private_->file != stdin)
 690                         fclose(decoder->private_->file);
 691                 decoder->private_->file = 0;
 692         }
 693
 694         if(decoder->private_->do_md5_checking) {
 695                 if(memcmp(decoder->private_->stream_info.data.stream_info.md5sum, decoder->private_->computed_md5sum, 16))
 696                         md5_failed = true;
 697         }
 698         decoder->private_->is_seeking = false;
 699
 700         set_defaults_(decoder);
 701
 702         decoder->protected_->state = FLAC__STREAM_DECODER_UNINITIALIZED;
 703
 704         return !md5_failed;
 705 }
 706
 707 FLAC_API FLAC__bool FLAC__stream_decoder_set_ogg_serial_number(FLAC__StreamDecoder *decoder, long value)
 708 {
 709         FLAC__ASSERT(0 != decoder);
 710         FLAC__ASSERT(0 != decoder->private_);
 711         FLAC__ASSERT(0 != decoder->protected_);
 712         if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
 713                 return false;
 714 #if FLAC__HAS_OGG
 715         /* can't check decoder->private_->is_ogg since that's not set until init time */
 716         FLAC__ogg_decoder_aspect_set_serial_number(&decoder->protected_->ogg_decoder_aspect, value);
 717         return true;
 718 #else
 719         (void)value;
 720         return false;
 721 #endif
 722 }
 723
 724 FLAC_API FLAC__bool FLAC__stream_decoder_set_md5_checking(FLAC__StreamDecoder *decoder, FLAC__bool value)
 725 {
 726         FLAC__ASSERT(0 != decoder);
 727         FLAC__ASSERT(0 != decoder->protected_);
 728         if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
 729                 return false;
 730         decoder->protected_->md5_checking = value;
 731         return true;
 732 }
 733
 734 FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_respond(FLAC__StreamDecoder *decoder, FLAC__MetadataType type)
 735 {
 736         FLAC__ASSERT(0 != decoder);
 737         FLAC__ASSERT(0 != decoder->private_);
 738         FLAC__ASSERT(0 != decoder->protected_);
 739         FLAC__ASSERT((unsigned)type <= FLAC__MAX_METADATA_TYPE_CODE);
 740         /* double protection */
 741         if((unsigned)type > FLAC__MAX_METADATA_TYPE_CODE)
 742                 return false;
 743         if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
 744                 return false;
 745         decoder->private_->metadata_filter[type] = true;
 746         if(type == FLAC__METADATA_TYPE_APPLICATION)
 747                 decoder->private_->metadata_filter_ids_count = 0;
 748         return true;
 749 }
 750
 751 FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_respond_application(FLAC__StreamDecoder *decoder, const FLAC__byte id[4])
 752 {
 753         FLAC__ASSERT(0 != decoder);
 754         FLAC__ASSERT(0 != decoder->private_);
 755         FLAC__ASSERT(0 != decoder->protected_);
 756         FLAC__ASSERT(0 != id);
 757         if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
 758                 return false;
 759
 760         if(decoder->private_->metadata_filter[FLAC__METADATA_TYPE_APPLICATION])
 761                 return true;
 762
 763         FLAC__ASSERT(0 != decoder->private_->metadata_filter_ids);
 764
 765         if(decoder->private_->metadata_filter_ids_count == decoder->private_->metadata_filter_ids_capacity) {
 766                 if(0 == (decoder->private_->metadata_filter_ids = safe_realloc_mul_2op_(decoder->private_->metadata_filter_ids, decoder->private_->metadata_filter_ids_capacity, /*times*/2))) {
 767                         decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
 768                         return false;
 769                 }
 770                 decoder->private_->metadata_filter_ids_capacity *= 2;
 771         }
 772
 773         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));
 774         decoder->private_->metadata_filter_ids_count++;
 775
 776         return true;
 777 }
 778
 779 FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_respond_all(FLAC__StreamDecoder *decoder)
 780 {
 781         unsigned i;
 782         FLAC__ASSERT(0 != decoder);
 783         FLAC__ASSERT(0 != decoder->private_);
 784         FLAC__ASSERT(0 != decoder->protected_);
 785         if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
 786                 return false;
 787         for(i = 0; i < sizeof(decoder->private_->metadata_filter) / sizeof(decoder->private_->metadata_filter[0]); i++)
 788                 decoder->private_->metadata_filter[i] = true;
 789         decoder->private_->metadata_filter_ids_count = 0;
 790         return true;
 791 }
 792
 793 FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_ignore(FLAC__StreamDecoder *decoder, FLAC__MetadataType type)
 794 {
 795         FLAC__ASSERT(0 != decoder);
 796         FLAC__ASSERT(0 != decoder->private_);
 797         FLAC__ASSERT(0 != decoder->protected_);
 798         FLAC__ASSERT((unsigned)type <= FLAC__MAX_METADATA_TYPE_CODE);
 799         /* double protection */
 800         if((unsigned)type > FLAC__MAX_METADATA_TYPE_CODE)
 801                 return false;
 802         if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
 803                 return false;
 804         decoder->private_->metadata_filter[type] = false;
 805         if(type == FLAC__METADATA_TYPE_APPLICATION)
 806                 decoder->private_->metadata_filter_ids_count = 0;
 807         return true;
 808 }
 809
 810 FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_ignore_application(FLAC__StreamDecoder *decoder, const FLAC__byte id[4])
 811 {
 812         FLAC__ASSERT(0 != decoder);
 813         FLAC__ASSERT(0 != decoder->private_);
 814         FLAC__ASSERT(0 != decoder->protected_);
 815         FLAC__ASSERT(0 != id);
 816         if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
 817                 return false;
 818
 819         if(!decoder->private_->metadata_filter[FLAC__METADATA_TYPE_APPLICATION])
 820                 return true;
 821
 822         FLAC__ASSERT(0 != decoder->private_->metadata_filter_ids);
 823
 824         if(decoder->private_->metadata_filter_ids_count == decoder->private_->metadata_filter_ids_capacity) {
 825                 if(0 == (decoder->private_->metadata_filter_ids = safe_realloc_mul_2op_(decoder->private_->metadata_filter_ids, decoder->private_->metadata_filter_ids_capacity, /*times*/2))) {
 826                         decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
 827                         return false;
 828                 }
 829                 decoder->private_->metadata_filter_ids_capacity *= 2;
 830         }
 831
 832         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));
 833         decoder->private_->metadata_filter_ids_count++;
 834
 835         return true;
 836 }
 837
 838 FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_ignore_all(FLAC__StreamDecoder *decoder)
 839 {
 840         FLAC__ASSERT(0 != decoder);
 841         FLAC__ASSERT(0 != decoder->private_);
 842         FLAC__ASSERT(0 != decoder->protected_);
 843         if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
 844                 return false;
 845         memset(decoder->private_->metadata_filter, 0, sizeof(decoder->private_->metadata_filter));
 846         decoder->private_->metadata_filter_ids_count = 0;
 847         return true;
 848 }
 849
 850 FLAC_API FLAC__StreamDecoderState FLAC__stream_decoder_get_state(const FLAC__StreamDecoder *decoder)
 851 {
 852         FLAC__ASSERT(0 != decoder);
 853         FLAC__ASSERT(0 != decoder->protected_);
 854         return decoder->protected_->state;
 855 }
 856
 857 FLAC_API const char *FLAC__stream_decoder_get_resolved_state_string(const FLAC__StreamDecoder *decoder)
 858 {
 859         return FLAC__StreamDecoderStateString[decoder->protected_->state];
 860 }
 861
 862 FLAC_API FLAC__bool FLAC__stream_decoder_get_md5_checking(const FLAC__StreamDecoder *decoder)
 863 {
 864         FLAC__ASSERT(0 != decoder);
 865         FLAC__ASSERT(0 != decoder->protected_);
 866         return decoder->protected_->md5_checking;
 867 }
 868
 869 FLAC_API FLAC__uint64 FLAC__stream_decoder_get_total_samples(const FLAC__StreamDecoder *decoder)
 870 {
 871         FLAC__ASSERT(0 != decoder);
 872         FLAC__ASSERT(0 != decoder->protected_);
 873         return decoder->private_->has_stream_info? decoder->private_->stream_info.data.stream_info.total_samples : 0;
 874 }
 875
 876 FLAC_API unsigned FLAC__stream_decoder_get_channels(const FLAC__StreamDecoder *decoder)
 877 {
 878         FLAC__ASSERT(0 != decoder);
 879         FLAC__ASSERT(0 != decoder->protected_);
 880         return decoder->protected_->channels;
 881 }
 882
 883 FLAC_API FLAC__ChannelAssignment FLAC__stream_decoder_get_channel_assignment(const FLAC__StreamDecoder *decoder)
 884 {
 885         FLAC__ASSERT(0 != decoder);
 886         FLAC__ASSERT(0 != decoder->protected_);
 887         return decoder->protected_->channel_assignment;
 888 }
 889
 890 FLAC_API unsigned FLAC__stream_decoder_get_bits_per_sample(const FLAC__StreamDecoder *decoder)
 891 {
 892         FLAC__ASSERT(0 != decoder);
 893         FLAC__ASSERT(0 != decoder->protected_);
 894         return decoder->protected_->bits_per_sample;
 895 }
 896
 897 FLAC_API unsigned FLAC__stream_decoder_get_sample_rate(const FLAC__StreamDecoder *decoder)
 898 {
 899         FLAC__ASSERT(0 != decoder);
 900         FLAC__ASSERT(0 != decoder->protected_);
 901         return decoder->protected_->sample_rate;
 902 }
 903
 904 FLAC_API unsigned FLAC__stream_decoder_get_blocksize(const FLAC__StreamDecoder *decoder)
 905 {
 906         FLAC__ASSERT(0 != decoder);
 907         FLAC__ASSERT(0 != decoder->protected_);
 908         return decoder->protected_->blocksize;
 909 }
 910
 911 FLAC_API FLAC__bool FLAC__stream_decoder_get_decode_position(const FLAC__StreamDecoder *decoder, FLAC__uint64 *position)
 912 {
 913         FLAC__ASSERT(0 != decoder);
 914         FLAC__ASSERT(0 != decoder->private_);
 915         FLAC__ASSERT(0 != position);
 916
 917 #if FLAC__HAS_OGG
 918         if(decoder->private_->is_ogg)
 919                 return false;
 920 #endif
 921         if(0 == decoder->private_->tell_callback)
 922                 return false;
 923         if(decoder->private_->tell_callback(decoder, position, decoder->private_->client_data) != FLAC__STREAM_DECODER_TELL_STATUS_OK)
 924                 return false;
 925         /* should never happen since all FLAC frames and metadata blocks are byte aligned, but check just in case */
 926         if(!FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input))
 927                 return false;
 928         FLAC__ASSERT(*position >= FLAC__stream_decoder_get_input_bytes_unconsumed(decoder));
 929         *position -= FLAC__stream_decoder_get_input_bytes_unconsumed(decoder);
 930         return true;
 931 }
 932
 933 FLAC_API FLAC__bool FLAC__stream_decoder_flush(FLAC__StreamDecoder *decoder)
 934 {
 935         FLAC__ASSERT(0 != decoder);
 936         FLAC__ASSERT(0 != decoder->private_);
 937         FLAC__ASSERT(0 != decoder->protected_);
 938
 939         decoder->private_->samples_decoded = 0;
 940         decoder->private_->do_md5_checking = false;
 941
 942 #if FLAC__HAS_OGG
 943         if(decoder->private_->is_ogg)
 944                 FLAC__ogg_decoder_aspect_flush(&decoder->protected_->ogg_decoder_aspect);
 945 #endif
 946
 947         if(!FLAC__bitreader_clear(decoder->private_->input)) {
 948                 decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
 949                 return false;
 950         }
 951         decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
 952
 953         return true;
 954 }
 955
 956 FLAC_API FLAC__bool FLAC__stream_decoder_reset(FLAC__StreamDecoder *decoder)
 957 {
 958         FLAC__ASSERT(0 != decoder);
 959         FLAC__ASSERT(0 != decoder->private_);
 960         FLAC__ASSERT(0 != decoder->protected_);
 961
 962         if(!FLAC__stream_decoder_flush(decoder)) {
 963                 /* above call sets the state for us */
 964                 return false;
 965         }
 966
 967 #if FLAC__HAS_OGG
 968         /*@@@ could go in !internal_reset_hack block below */
 969         if(decoder->private_->is_ogg)
 970                 FLAC__ogg_decoder_aspect_reset(&decoder->protected_->ogg_decoder_aspect);
 971 #endif
 972
 973         /* Rewind if necessary.  If FLAC__stream_decoder_init() is calling us,
 974          * (internal_reset_hack) don't try to rewind since we are already at
 975          * the beginning of the stream and don't want to fail if the input is
 976          * not seekable.
 977          */
 978         if(!decoder->private_->internal_reset_hack) {
 979                 if(decoder->private_->file == stdin)
 980                         return false; /* can't rewind stdin, reset fails */
 981                 if(decoder->private_->seek_callback && decoder->private_->seek_callback(decoder, 0, decoder->private_->client_data) == FLAC__STREAM_DECODER_SEEK_STATUS_ERROR)
 982                         return false; /* seekable and seek fails, reset fails */
 983         }
 984         else
 985                 decoder->private_->internal_reset_hack = false;
 986
 987         decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_METADATA;
 988
 989         decoder->private_->has_stream_info = false;
 990         if(decoder->private_->has_seek_table && 0 != decoder->private_->seek_table.data.seek_table.points) {
 991                 free(decoder->private_->seek_table.data.seek_table.points);
 992                 decoder->private_->seek_table.data.seek_table.points = 0;
 993                 decoder->private_->has_seek_table = false;
 994         }
 995         decoder->private_->do_md5_checking = decoder->protected_->md5_checking;
 996         /*
 997          * This goes in reset() and not flush() because according to the spec, a
 998          * fixed-blocksize stream must stay that way through the whole stream.
 999          */
1000         decoder->private_->fixed_block_size = decoder->private_->next_fixed_block_size = 0;
1001
1002         /* We initialize the FLAC__MD5Context even though we may never use it.  This
1003          * is because md5 checking may be turned on to start and then turned off if
1004          * a seek occurs.  So we init the context here and finalize it in
1005          * FLAC__stream_decoder_finish() to make sure things are always cleaned up
1006          * properly.
1007          */
1008         FLAC__MD5Init(&decoder->private_->md5context);
1009
1010         decoder->private_->first_frame_offset = 0;
1011         decoder->private_->unparseable_frame_count = 0;
1012
1013         return true;
1014 }
1015
1016 FLAC_API FLAC__bool FLAC__stream_decoder_process_single(FLAC__StreamDecoder *decoder)
1017 {
1018         FLAC__bool got_a_frame;
1019         FLAC__ASSERT(0 != decoder);
1020         FLAC__ASSERT(0 != decoder->protected_);
1021
1022         while(1) {
1023                 switch(decoder->protected_->state) {
1024                         case FLAC__STREAM_DECODER_SEARCH_FOR_METADATA:
1025                                 if(!find_metadata_(decoder))
1026                                         return false; /* above function sets the status for us */
1027                                 break;
1028                         case FLAC__STREAM_DECODER_READ_METADATA:
1029                                 if(!read_metadata_(decoder))
1030                                         return false; /* above function sets the status for us */
1031                                 else
1032                                         return true;
1033                         case FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC:
1034                                 if(!frame_sync_(decoder))
1035                                         return true; /* above function sets the status for us */
1036                                 break;
1037                         case FLAC__STREAM_DECODER_READ_FRAME:
1038                                 if(!read_frame_(decoder, &got_a_frame, /*do_full_decode=*/true))
1039                                         return false; /* above function sets the status for us */
1040                                 if(got_a_frame)
1041                                         return true; /* above function sets the status for us */
1042                                 break;
1043                         case FLAC__STREAM_DECODER_END_OF_STREAM:
1044                         case FLAC__STREAM_DECODER_ABORTED:
1045                                 return true;
1046                         default:
1047                                 FLAC__ASSERT(0);
1048                                 return false;
1049                 }
1050         }
1051 }
1052
1053 FLAC_API FLAC__bool FLAC__stream_decoder_process_until_end_of_metadata(FLAC__StreamDecoder *decoder)
1054 {
1055         FLAC__ASSERT(0 != decoder);
1056         FLAC__ASSERT(0 != decoder->protected_);
1057
1058         while(1) {
1059                 switch(decoder->protected_->state) {
1060                         case FLAC__STREAM_DECODER_SEARCH_FOR_METADATA:
1061                                 if(!find_metadata_(decoder))
1062                                         return false; /* above function sets the status for us */
1063                                 break;
1064                         case FLAC__STREAM_DECODER_READ_METADATA:
1065                                 if(!read_metadata_(decoder))
1066                                         return false; /* above function sets the status for us */
1067                                 break;
1068                         case FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC:
1069                         case FLAC__STREAM_DECODER_READ_FRAME:
1070                         case FLAC__STREAM_DECODER_END_OF_STREAM:
1071                         case FLAC__STREAM_DECODER_ABORTED:
1072                                 return true;
1073                         default:
1074                                 FLAC__ASSERT(0);
1075                                 return false;
1076                 }
1077         }
1078 }
1079
1080 FLAC_API FLAC__bool FLAC__stream_decoder_process_until_end_of_stream(FLAC__StreamDecoder *decoder)
1081 {
1082         FLAC__bool dummy;
1083         FLAC__ASSERT(0 != decoder);
1084         FLAC__ASSERT(0 != decoder->protected_);
1085
1086         while(1) {
1087                 switch(decoder->protected_->state) {
1088                         case FLAC__STREAM_DECODER_SEARCH_FOR_METADATA:
1089                                 if(!find_metadata_(decoder))
1090                                         return false; /* above function sets the status for us */
1091                                 break;
1092                         case FLAC__STREAM_DECODER_READ_METADATA:
1093                                 if(!read_metadata_(decoder))
1094                                         return false; /* above function sets the status for us */
1095                                 break;
1096                         case FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC:
1097                                 if(!frame_sync_(decoder))
1098                                         return true; /* above function sets the status for us */
1099                                 break;
1100                         case FLAC__STREAM_DECODER_READ_FRAME:
1101                                 if(!read_frame_(decoder, &dummy, /*do_full_decode=*/true))
1102                                         return false; /* above function sets the status for us */
1103                                 break;
1104                         case FLAC__STREAM_DECODER_END_OF_STREAM:
1105                         case FLAC__STREAM_DECODER_ABORTED:
1106                                 return true;
1107                         default:
1108                                 FLAC__ASSERT(0);
1109                                 return false;
1110                 }
1111         }
1112 }
1113
1114 FLAC_API FLAC__bool FLAC__stream_decoder_skip_single_frame(FLAC__StreamDecoder *decoder)
1115 {
1116         FLAC__bool got_a_frame;
1117         FLAC__ASSERT(0 != decoder);
1118         FLAC__ASSERT(0 != decoder->protected_);
1119
1120         while(1) {
1121                 switch(decoder->protected_->state) {
1122                         case FLAC__STREAM_DECODER_SEARCH_FOR_METADATA:
1123                         case FLAC__STREAM_DECODER_READ_METADATA:
1124                                 return false; /* above function sets the status for us */
1125                         case FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC:
1126                                 if(!frame_sync_(decoder))
1127                                         return true; /* above function sets the status for us */
1128                                 break;
1129                         case FLAC__STREAM_DECODER_READ_FRAME:
1130                                 if(!read_frame_(decoder, &got_a_frame, /*do_full_decode=*/false))
1131                                         return false; /* above function sets the status for us */
1132                                 if(got_a_frame)
1133                                         return true; /* above function sets the status for us */
1134                                 break;
1135                         case FLAC__STREAM_DECODER_END_OF_STREAM:
1136                         case FLAC__STREAM_DECODER_ABORTED:
1137                                 return true;
1138                         default:
1139                                 FLAC__ASSERT(0);
1140                                 return false;
1141                 }
1142         }
1143 }
1144
1145 FLAC_API FLAC__bool FLAC__stream_decoder_seek_absolute(FLAC__StreamDecoder *decoder, FLAC__uint64 sample)
1146 {
1147         FLAC__uint64 length;
1148
1149         FLAC__ASSERT(0 != decoder);
1150
1151         if(
1152                 decoder->protected_->state != FLAC__STREAM_DECODER_SEARCH_FOR_METADATA &&
1153                 decoder->protected_->state != FLAC__STREAM_DECODER_READ_METADATA &&
1154                 decoder->protected_->state != FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC &&
1155                 decoder->protected_->state != FLAC__STREAM_DECODER_READ_FRAME &&
1156                 decoder->protected_->state != FLAC__STREAM_DECODER_END_OF_STREAM
1157         )
1158                 return false;
1159
1160         if(0 == decoder->private_->seek_callback)
1161                 return false;
1162
1163         FLAC__ASSERT(decoder->private_->seek_callback);
1164         FLAC__ASSERT(decoder->private_->tell_callback);
1165         FLAC__ASSERT(decoder->private_->length_callback);
1166         FLAC__ASSERT(decoder->private_->eof_callback);
1167
1168         if(FLAC__stream_decoder_get_total_samples(decoder) > 0 && sample >= FLAC__stream_decoder_get_total_samples(decoder))
1169                 return false;
1170
1171         decoder->private_->is_seeking = true;
1172
1173         /* turn off md5 checking if a seek is attempted */
1174         decoder->private_->do_md5_checking = false;
1175
1176         /* get the file length (currently our algorithm needs to know the length so it's also an error to get FLAC__STREAM_DECODER_LENGTH_STATUS_UNSUPPORTED) */
1177         if(decoder->private_->length_callback(decoder, &length, decoder->private_->client_data) != FLAC__STREAM_DECODER_LENGTH_STATUS_OK) {
1178                 decoder->private_->is_seeking = false;
1179                 return false;
1180         }
1181
1182         /* if we haven't finished processing the metadata yet, do that so we have the STREAMINFO, SEEK_TABLE, and first_frame_offset */
1183         if(
1184                 decoder->protected_->state == FLAC__STREAM_DECODER_SEARCH_FOR_METADATA ||
1185                 decoder->protected_->state == FLAC__STREAM_DECODER_READ_METADATA
1186         ) {
1187                 if(!FLAC__stream_decoder_process_until_end_of_metadata(decoder)) {
1188                         /* above call sets the state for us */
1189                         decoder->private_->is_seeking = false;
1190                         return false;
1191                 }
1192                 /* check this again in case we didn't know total_samples the first time */
1193                 if(FLAC__stream_decoder_get_total_samples(decoder) > 0 && sample >= FLAC__stream_decoder_get_total_samples(decoder)) {
1194                         decoder->private_->is_seeking = false;
1195                         return false;
1196                 }
1197         }
1198
1199         {
1200                 const FLAC__bool ok =
1201 #if FLAC__HAS_OGG
1202                         decoder->private_->is_ogg?
1203                         seek_to_absolute_sample_ogg_(decoder, length, sample) :
1204 #endif
1205                         seek_to_absolute_sample_(decoder, length, sample)
1206                 ;
1207                 decoder->private_->is_seeking = false;
1208                 return ok;
1209         }
1210 }
1211
1212 /***********************************************************************
1213  *
1214  * Protected class methods
1215  *
1216  ***********************************************************************/
1217
1218 unsigned FLAC__stream_decoder_get_input_bytes_unconsumed(const FLAC__StreamDecoder *decoder)
1219 {
1220         FLAC__ASSERT(0 != decoder);
1221         FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));
1222         FLAC__ASSERT(!(FLAC__bitreader_get_input_bits_unconsumed(decoder->private_->input) & 7));
1223         return FLAC__bitreader_get_input_bits_unconsumed(decoder->private_->input) / 8;
1224 }
1225
1226 /***********************************************************************
1227  *
1228  * Private class methods
1229  *
1230  ***********************************************************************/
1231
1232 void set_defaults_(FLAC__StreamDecoder *decoder)
1233 {
1234 #if FLAC__HAS_OGG
1235         decoder->private_->is_ogg = false;
1236 #endif
1237         decoder->private_->read_callback = 0;
1238         decoder->private_->seek_callback = 0;
1239         decoder->private_->tell_callback = 0;
1240         decoder->private_->length_callback = 0;
1241         decoder->private_->eof_callback = 0;
1242         decoder->private_->write_callback = 0;
1243         decoder->private_->metadata_callback = 0;
1244         decoder->private_->error_callback = 0;
1245         decoder->private_->client_data = 0;
1246
1247         memset(decoder->private_->metadata_filter, 0, sizeof(decoder->private_->metadata_filter));
1248         decoder->private_->metadata_filter[FLAC__METADATA_TYPE_STREAMINFO] = true;
1249         decoder->private_->metadata_filter_ids_count = 0;
1250
1251         decoder->protected_->md5_checking = false;
1252
1253 #if FLAC__HAS_OGG
1254         FLAC__ogg_decoder_aspect_set_defaults(&decoder->protected_->ogg_decoder_aspect);
1255 #endif
1256 }
1257
1258 /*
1259  * This will forcibly set stdin to binary mode (for OSes that require it)
1260  */
1261 FILE *get_binary_stdin_(void)
1262 {
1263         /* if something breaks here it is probably due to the presence or
1264          * absence of an underscore before the identifiers 'setmode',
1265          * 'fileno', and/or 'O_BINARY'; check your system header files.
1266          */
1267 #if defined _MSC_VER || defined __MINGW32__
1268         _setmode(_fileno(stdin), _O_BINARY);
1269 #elif defined __CYGWIN__
1270         /* almost certainly not needed for any modern Cygwin, but let's be safe... */
1271         setmode(_fileno(stdin), _O_BINARY);
1272 #elif defined __EMX__
1273         setmode(fileno(stdin), O_BINARY);
1274 #endif
1275
1276         return stdin;
1277 }
1278
1279 FLAC__bool allocate_output_(FLAC__StreamDecoder *decoder, unsigned size, unsigned channels)
1280 {
1281         unsigned i;
1282         FLAC__int32 *tmp;
1283
1284         if(size <= decoder->private_->output_capacity && channels <= decoder->private_->output_channels)
1285                 return true;
1286
1287         /* simply using realloc() is not practical because the number of channels may change mid-stream */
1288
1289         for(i = 0; i < FLAC__MAX_CHANNELS; i++) {
1290                 if(0 != decoder->private_->output[i]) {
1291                         free(decoder->private_->output[i]-4);
1292                         decoder->private_->output[i] = 0;
1293                 }
1294                 if(0 != decoder->private_->residual_unaligned[i]) {
1295                         free(decoder->private_->residual_unaligned[i]);
1296                         decoder->private_->residual_unaligned[i] = decoder->private_->residual[i] = 0;
1297                 }
1298         }
1299
1300         for(i = 0; i < channels; i++) {
1301                 /* WATCHOUT:
1302                  * FLAC__lpc_restore_signal_asm_ia32_mmx() requires that the
1303                  * output arrays have a buffer of up to 3 zeroes in front
1304                  * (at negative indices) for alignment purposes; we use 4
1305                  * to keep the data well-aligned.
1306                  */
1307                 tmp = safe_malloc_muladd2_(sizeof(FLAC__int32), /*times (*/size, /*+*/4/*)*/);
1308                 if(tmp == 0) {
1309                         decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1310                         return false;
1311                 }
1312                 memset(tmp, 0, sizeof(FLAC__int32)*4);
1313                 decoder->private_->output[i] = tmp + 4;
1314
1315                 /* WATCHOUT:
1316                  * minimum of quadword alignment for PPC vector optimizations is REQUIRED:
1317                  */
1318                 if(!FLAC__memory_alloc_aligned_int32_array(size, &decoder->private_->residual_unaligned[i], &decoder->private_->residual[i])) {
1319                         decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1320                         return false;
1321                 }
1322         }
1323
1324         decoder->private_->output_capacity = size;
1325         decoder->private_->output_channels = channels;
1326
1327         return true;
1328 }
1329
1330 FLAC__bool has_id_filtered_(FLAC__StreamDecoder *decoder, FLAC__byte *id)
1331 {
1332         size_t i;
1333
1334         FLAC__ASSERT(0 != decoder);
1335         FLAC__ASSERT(0 != decoder->private_);
1336
1337         for(i = 0; i < decoder->private_->metadata_filter_ids_count; i++)
1338                 if(0 == memcmp(decoder->private_->metadata_filter_ids + i * (FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8), id, (FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8)))
1339                         return true;
1340
1341         return false;
1342 }
1343
1344 FLAC__bool find_metadata_(FLAC__StreamDecoder *decoder)
1345 {
1346         FLAC__uint32 x;
1347         unsigned i, id;
1348         FLAC__bool first = true;
1349
1350         FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));
1351
1352         for(i = id = 0; i < 4; ) {
1353                 if(decoder->private_->cached) {
1354                         x = (FLAC__uint32)decoder->private_->lookahead;
1355                         decoder->private_->cached = false;
1356                 }
1357                 else {
1358                         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
1359                                 return false; /* read_callback_ sets the state for us */
1360                 }
1361                 if(x == FLAC__STREAM_SYNC_STRING[i]) {
1362                         first = true;
1363                         i++;
1364                         id = 0;
1365                         continue;
1366                 }
1367                 if(x == ID3V2_TAG_[id]) {
1368                         id++;
1369                         i = 0;
1370                         if(id == 3) {
1371                                 if(!skip_id3v2_tag_(decoder))
1372                                         return false; /* skip_id3v2_tag_ sets the state for us */
1373                         }
1374                         continue;
1375                 }
1376                 id = 0;
1377                 if(x == 0xff) { /* MAGIC NUMBER for the first 8 frame sync bits */
1378                         decoder->private_->header_warmup[0] = (FLAC__byte)x;
1379                         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
1380                                 return false; /* read_callback_ sets the state for us */
1381
1382                         /* 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 */
1383                         /* else we have to check if the second byte is the end of a sync code */
1384                         if(x == 0xff) { /* MAGIC NUMBER for the first 8 frame sync bits */
1385                                 decoder->private_->lookahead = (FLAC__byte)x;
1386                                 decoder->private_->cached = true;
1387                         }
1388                         else if(x >> 1 == 0x7c) { /* MAGIC NUMBER for the last 6 sync bits and reserved 7th bit */
1389                                 decoder->private_->header_warmup[1] = (FLAC__byte)x;
1390                                 decoder->protected_->state = FLAC__STREAM_DECODER_READ_FRAME;
1391                                 return true;
1392                         }
1393                 }
1394                 i = 0;
1395                 if(first) {
1396                         send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
1397                         first = false;
1398                 }
1399         }
1400
1401         decoder->protected_->state = FLAC__STREAM_DECODER_READ_METADATA;
1402         return true;
1403 }
1404
1405 FLAC__bool read_metadata_(FLAC__StreamDecoder *decoder)
1406 {
1407         FLAC__bool is_last;
1408         FLAC__uint32 i, x, type, length;
1409
1410         FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));
1411
1412         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_IS_LAST_LEN))
1413                 return false; /* read_callback_ sets the state for us */
1414         is_last = x? true : false;
1415
1416         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &type, FLAC__STREAM_METADATA_TYPE_LEN))
1417                 return false; /* read_callback_ sets the state for us */
1418
1419         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &length, FLAC__STREAM_METADATA_LENGTH_LEN))
1420                 return false; /* read_callback_ sets the state for us */
1421
1422         if(type == FLAC__METADATA_TYPE_STREAMINFO) {
1423                 if(!read_metadata_streaminfo_(decoder, is_last, length))
1424                         return false;
1425
1426                 decoder->private_->has_stream_info = true;
1427                 if(0 == memcmp(decoder->private_->stream_info.data.stream_info.md5sum, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0", 16))
1428                         decoder->private_->do_md5_checking = false;
1429                 if(!decoder->private_->is_seeking && decoder->private_->metadata_filter[FLAC__METADATA_TYPE_STREAMINFO] && decoder->private_->metadata_callback)
1430                         decoder->private_->metadata_callback(decoder, &decoder->private_->stream_info, decoder->private_->client_data);
1431         }
1432         else if(type == FLAC__METADATA_TYPE_SEEKTABLE) {
1433                 if(!read_metadata_seektable_(decoder, is_last, length))
1434                         return false;
1435
1436                 decoder->private_->has_seek_table = true;
1437                 if(!decoder->private_->is_seeking && decoder->private_->metadata_filter[FLAC__METADATA_TYPE_SEEKTABLE] && decoder->private_->metadata_callback)
1438                         decoder->private_->metadata_callback(decoder, &decoder->private_->seek_table, decoder->private_->client_data);
1439         }
1440         else {
1441                 FLAC__bool skip_it = !decoder->private_->metadata_filter[type];
1442                 unsigned real_length = length;
1443                 FLAC__StreamMetadata block;
1444
1445                 block.is_last = is_last;
1446                 block.type = (FLAC__MetadataType)type;
1447                 block.length = length;
1448
1449                 if(type == FLAC__METADATA_TYPE_APPLICATION) {
1450                         if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, block.data.application.id, FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8))
1451                                 return false; /* read_callback_ sets the state for us */
1452
1453                         if(real_length < FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8) { /* underflow check */
1454                                 decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;/*@@@@@@ maybe wrong error? need to resync?*/
1455                                 return false;
1456                         }
1457
1458                         real_length -= FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8;
1459
1460                         if(decoder->private_->metadata_filter_ids_count > 0 && has_id_filtered_(decoder, block.data.application.id))
1461                                 skip_it = !skip_it;
1462                 }
1463
1464                 if(skip_it) {
1465                         if(!FLAC__bitreader_skip_byte_block_aligned_no_crc(decoder->private_->input, real_length))
1466                                 return false; /* read_callback_ sets the state for us */
1467                 }
1468                 else {
1469                         switch(type) {
1470                                 case FLAC__METADATA_TYPE_PADDING:
1471                                         /* skip the padding bytes */
1472                                         if(!FLAC__bitreader_skip_byte_block_aligned_no_crc(decoder->private_->input, real_length))
1473                                                 return false; /* read_callback_ sets the state for us */
1474                                         break;
1475                                 case FLAC__METADATA_TYPE_APPLICATION:
1476                                         /* remember, we read the ID already */
1477                                         if(real_length > 0) {
1478                                                 if(0 == (block.data.application.data = malloc(real_length))) {
1479                                                         decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1480                                                         return false;
1481                                                 }
1482                                                 if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, block.data.application.data, real_length))
1483                                                         return false; /* read_callback_ sets the state for us */
1484                                         }
1485                                         else
1486                                                 block.data.application.data = 0;
1487                                         break;
1488                                 case FLAC__METADATA_TYPE_VORBIS_COMMENT:
1489                                         if(!read_metadata_vorbiscomment_(decoder, &block.data.vorbis_comment))
1490                                                 return false;
1491                                         break;
1492                                 case FLAC__METADATA_TYPE_CUESHEET:
1493                                         if(!read_metadata_cuesheet_(decoder, &block.data.cue_sheet))
1494                                                 return false;
1495                                         break;
1496                                 case FLAC__METADATA_TYPE_PICTURE:
1497                                         if(!read_metadata_picture_(decoder, &block.data.picture))
1498                                                 return false;
1499                                         break;
1500                                 case FLAC__METADATA_TYPE_STREAMINFO:
1501                                 case FLAC__METADATA_TYPE_SEEKTABLE:
1502                                         FLAC__ASSERT(0);
1503                                         break;
1504                                 default:
1505                                         if(real_length > 0) {
1506                                                 if(0 == (block.data.unknown.data = malloc(real_length))) {
1507                                                         decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1508                                                         return false;
1509                                                 }
1510                                                 if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, block.data.unknown.data, real_length))
1511                                                         return false; /* read_callback_ sets the state for us */
1512                                         }
1513                                         else
1514                                                 block.data.unknown.data = 0;
1515                                         break;
1516                         }
1517                         if(!decoder->private_->is_seeking && decoder->private_->metadata_callback)
1518                                 decoder->private_->metadata_callback(decoder, &block, decoder->private_->client_data);
1519
1520                         /* now we have to free any malloc()ed data in the block */
1521                         switch(type) {
1522                                 case FLAC__METADATA_TYPE_PADDING:
1523                                         break;
1524                                 case FLAC__METADATA_TYPE_APPLICATION:
1525                                         if(0 != block.data.application.data)
1526                                                 free(block.data.application.data);
1527                                         break;
1528                                 case FLAC__METADATA_TYPE_VORBIS_COMMENT:
1529                                         if(0 != block.data.vorbis_comment.vendor_string.entry)
1530                                                 free(block.data.vorbis_comment.vendor_string.entry);
1531                                         if(block.data.vorbis_comment.num_comments > 0)
1532                                                 for(i = 0; i < block.data.vorbis_comment.num_comments; i++)
1533                                                         if(0 != block.data.vorbis_comment.comments[i].entry)
1534                                                                 free(block.data.vorbis_comment.comments[i].entry);
1535                                         if(0 != block.data.vorbis_comment.comments)
1536                                                 free(block.data.vorbis_comment.comments);
1537                                         break;
1538                                 case FLAC__METADATA_TYPE_CUESHEET:
1539                                         if(block.data.cue_sheet.num_tracks > 0)
1540                                                 for(i = 0; i < block.data.cue_sheet.num_tracks; i++)
1541                                                         if(0 != block.data.cue_sheet.tracks[i].indices)
1542                                                                 free(block.data.cue_sheet.tracks[i].indices);
1543                                         if(0 != block.data.cue_sheet.tracks)
1544                                                 free(block.data.cue_sheet.tracks);
1545                                         break;
1546                                 case FLAC__METADATA_TYPE_PICTURE:
1547                                         if(0 != block.data.picture.mime_type)
1548                                                 free(block.data.picture.mime_type);
1549                                         if(0 != block.data.picture.description)
1550                                                 free(block.data.picture.description);
1551                                         if(0 != block.data.picture.data)
1552                                                 free(block.data.picture.data);
1553                                         break;
1554                                 case FLAC__METADATA_TYPE_STREAMINFO:
1555                                 case FLAC__METADATA_TYPE_SEEKTABLE:
1556                                         FLAC__ASSERT(0);
1557                                 default:
1558                                         if(0 != block.data.unknown.data)
1559                                                 free(block.data.unknown.data);
1560                                         break;
1561                         }
1562                 }
1563         }
1564
1565         if(is_last) {
1566                 /* if this fails, it's OK, it's just a hint for the seek routine */
1567                 if(!FLAC__stream_decoder_get_decode_position(decoder, &decoder->private_->first_frame_offset))
1568                         decoder->private_->first_frame_offset = 0;
1569                 decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
1570         }
1571
1572         return true;
1573 }
1574
1575 FLAC__bool read_metadata_streaminfo_(FLAC__StreamDecoder *decoder, FLAC__bool is_last, unsigned length)
1576 {
1577         FLAC__uint32 x;
1578         unsigned bits, used_bits = 0;
1579
1580         FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));
1581
1582         decoder->private_->stream_info.type = FLAC__METADATA_TYPE_STREAMINFO;
1583         decoder->private_->stream_info.is_last = is_last;
1584         decoder->private_->stream_info.length = length;
1585
1586         bits = FLAC__STREAM_METADATA_STREAMINFO_MIN_BLOCK_SIZE_LEN;
1587         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, bits))
1588                 return false; /* read_callback_ sets the state for us */
1589         decoder->private_->stream_info.data.stream_info.min_blocksize = x;
1590         used_bits += bits;
1591
1592         bits = FLAC__STREAM_METADATA_STREAMINFO_MAX_BLOCK_SIZE_LEN;
1593         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_MAX_BLOCK_SIZE_LEN))
1594                 return false; /* read_callback_ sets the state for us */
1595         decoder->private_->stream_info.data.stream_info.max_blocksize = x;
1596         used_bits += bits;
1597
1598         bits = FLAC__STREAM_METADATA_STREAMINFO_MIN_FRAME_SIZE_LEN;
1599         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_MIN_FRAME_SIZE_LEN))
1600                 return false; /* read_callback_ sets the state for us */
1601         decoder->private_->stream_info.data.stream_info.min_framesize = x;
1602         used_bits += bits;
1603
1604         bits = FLAC__STREAM_METADATA_STREAMINFO_MAX_FRAME_SIZE_LEN;
1605         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_MAX_FRAME_SIZE_LEN))
1606                 return false; /* read_callback_ sets the state for us */
1607         decoder->private_->stream_info.data.stream_info.max_framesize = x;
1608         used_bits += bits;
1609
1610         bits = FLAC__STREAM_METADATA_STREAMINFO_SAMPLE_RATE_LEN;
1611         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_SAMPLE_RATE_LEN))
1612                 return false; /* read_callback_ sets the state for us */
1613         decoder->private_->stream_info.data.stream_info.sample_rate = x;
1614         used_bits += bits;
1615
1616         bits = FLAC__STREAM_METADATA_STREAMINFO_CHANNELS_LEN;
1617         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_CHANNELS_LEN))
1618                 return false; /* read_callback_ sets the state for us */
1619         decoder->private_->stream_info.data.stream_info.channels = x+1;
1620         used_bits += bits;
1621
1622         bits = FLAC__STREAM_METADATA_STREAMINFO_BITS_PER_SAMPLE_LEN;
1623         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_BITS_PER_SAMPLE_LEN))
1624                 return false; /* read_callback_ sets the state for us */
1625         decoder->private_->stream_info.data.stream_info.bits_per_sample = x+1;
1626         used_bits += bits;
1627
1628         bits = FLAC__STREAM_METADATA_STREAMINFO_TOTAL_SAMPLES_LEN;
1629         if(!FLAC__bitreader_read_raw_uint64(decoder->private_->input, &decoder->private_->stream_info.data.stream_info.total_samples, FLAC__STREAM_METADATA_STREAMINFO_TOTAL_SAMPLES_LEN))
1630                 return false; /* read_callback_ sets the state for us */
1631         used_bits += bits;
1632
1633         if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, decoder->private_->stream_info.data.stream_info.md5sum, 16))
1634                 return false; /* read_callback_ sets the state for us */
1635         used_bits += 16*8;
1636
1637         /* skip the rest of the block */
1638         FLAC__ASSERT(used_bits % 8 == 0);
1639         length -= (used_bits / 8);
1640         if(!FLAC__bitreader_skip_byte_block_aligned_no_crc(decoder->private_->input, length))
1641                 return false; /* read_callback_ sets the state for us */
1642
1643         return true;
1644 }
1645
1646 FLAC__bool read_metadata_seektable_(FLAC__StreamDecoder *decoder, FLAC__bool is_last, unsigned length)
1647 {
1648         FLAC__uint32 i, x;
1649         FLAC__uint64 xx;
1650
1651         FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));
1652
1653         decoder->private_->seek_table.type = FLAC__METADATA_TYPE_SEEKTABLE;
1654         decoder->private_->seek_table.is_last = is_last;
1655         decoder->private_->seek_table.length = length;
1656
1657         decoder->private_->seek_table.data.seek_table.num_points = length / FLAC__STREAM_METADATA_SEEKPOINT_LENGTH;
1658
1659         /* use realloc since we may pass through here several times (e.g. after seeking) */
1660         if(0 == (decoder->private_->seek_table.data.seek_table.points = safe_realloc_mul_2op_(decoder->private_->seek_table.data.seek_table.points, decoder->private_->seek_table.data.seek_table.num_points, /*times*/sizeof(FLAC__StreamMetadata_SeekPoint)))) {
1661                 decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1662                 return false;
1663         }
1664         for(i = 0; i < decoder->private_->seek_table.data.seek_table.num_points; i++) {
1665                 if(!FLAC__bitreader_read_raw_uint64(decoder->private_->input, &xx, FLAC__STREAM_METADATA_SEEKPOINT_SAMPLE_NUMBER_LEN))
1666                         return false; /* read_callback_ sets the state for us */
1667                 decoder->private_->seek_table.data.seek_table.points[i].sample_number = xx;
1668
1669                 if(!FLAC__bitreader_read_raw_uint64(decoder->private_->input, &xx, FLAC__STREAM_METADATA_SEEKPOINT_STREAM_OFFSET_LEN))
1670                         return false; /* read_callback_ sets the state for us */
1671                 decoder->private_->seek_table.data.seek_table.points[i].stream_offset = xx;
1672
1673                 if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_SEEKPOINT_FRAME_SAMPLES_LEN))
1674                         return false; /* read_callback_ sets the state for us */
1675                 decoder->private_->seek_table.data.seek_table.points[i].frame_samples = x;
1676         }
1677         length -= (decoder->private_->seek_table.data.seek_table.num_points * FLAC__STREAM_METADATA_SEEKPOINT_LENGTH);
1678         /* if there is a partial point left, skip over it */
1679         if(length > 0) {
1680                 /*@@@ do a send_error_to_client_() here?  there's an argument for either way */
1681                 if(!FLAC__bitreader_skip_byte_block_aligned_no_crc(decoder->private_->input, length))
1682                         return false; /* read_callback_ sets the state for us */
1683         }
1684
1685         return true;
1686 }
1687
1688 FLAC__bool read_metadata_vorbiscomment_(FLAC__StreamDecoder *decoder, FLAC__StreamMetadata_VorbisComment *obj)
1689 {
1690         FLAC__uint32 i;
1691
1692         FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));
1693
1694         /* read vendor string */
1695         FLAC__ASSERT(FLAC__STREAM_METADATA_VORBIS_COMMENT_ENTRY_LENGTH_LEN == 32);
1696         if(!FLAC__bitreader_read_uint32_little_endian(decoder->private_->input, &obj->vendor_string.length))
1697                 return false; /* read_callback_ sets the state for us */
1698         if(obj->vendor_string.length > 0) {
1699                 if(0 == (obj->vendor_string.entry = safe_malloc_add_2op_(obj->vendor_string.length, /*+*/1))) {
1700                         decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1701                         return false;
1702                 }
1703                 if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, obj->vendor_string.entry, obj->vendor_string.length))
1704                         return false; /* read_callback_ sets the state for us */
1705                 obj->vendor_string.entry[obj->vendor_string.length] = '\0';
1706         }
1707         else
1708                 obj->vendor_string.entry = 0;
1709
1710         /* read num comments */
1711         FLAC__ASSERT(FLAC__STREAM_METADATA_VORBIS_COMMENT_NUM_COMMENTS_LEN == 32);
1712         if(!FLAC__bitreader_read_uint32_little_endian(decoder->private_->input, &obj->num_comments))
1713                 return false; /* read_callback_ sets the state for us */
1714
1715         /* read comments */
1716         if(obj->num_comments > 0) {
1717                 if(0 == (obj->comments = safe_malloc_mul_2op_p(obj->num_comments, /*times*/sizeof(FLAC__StreamMetadata_VorbisComment_Entry)))) {
1718                         decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1719                         return false;
1720                 }
1721                 for(i = 0; i < obj->num_comments; i++) {
1722                         FLAC__ASSERT(FLAC__STREAM_METADATA_VORBIS_COMMENT_ENTRY_LENGTH_LEN == 32);
1723                         if(!FLAC__bitreader_read_uint32_little_endian(decoder->private_->input, &obj->comments[i].length))
1724                                 return false; /* read_callback_ sets the state for us */
1725                         if(obj->comments[i].length > 0) {
1726                                 if(0 == (obj->comments[i].entry = safe_malloc_add_2op_(obj->comments[i].length, /*+*/1))) {
1727                                         decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1728                                         return false;
1729                                 }
1730                                 if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, obj->comments[i].entry, obj->comments[i].length))
1731                                         return false; /* read_callback_ sets the state for us */
1732                                 obj->comments[i].entry[obj->comments[i].length] = '\0';
1733                         }
1734                         else
1735                                 obj->comments[i].entry = 0;
1736                 }
1737         }
1738         else {
1739                 obj->comments = 0;
1740         }
1741
1742         return true;
1743 }
1744
1745 FLAC__bool read_metadata_cuesheet_(FLAC__StreamDecoder *decoder, FLAC__StreamMetadata_CueSheet *obj)
1746 {
1747         FLAC__uint32 i, j, x;
1748
1749         FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));
1750
1751         memset(obj, 0, sizeof(FLAC__StreamMetadata_CueSheet));
1752
1753         FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_MEDIA_CATALOG_NUMBER_LEN % 8 == 0);
1754         if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, (FLAC__byte*)obj->media_catalog_number, FLAC__STREAM_METADATA_CUESHEET_MEDIA_CATALOG_NUMBER_LEN/8))
1755                 return false; /* read_callback_ sets the state for us */
1756
1757         if(!FLAC__bitreader_read_raw_uint64(decoder->private_->input, &obj->lead_in, FLAC__STREAM_METADATA_CUESHEET_LEAD_IN_LEN))
1758                 return false; /* read_callback_ sets the state for us */
1759
1760         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_IS_CD_LEN))
1761                 return false; /* read_callback_ sets the state for us */
1762         obj->is_cd = x? true : false;
1763
1764         if(!FLAC__bitreader_skip_bits_no_crc(decoder->private_->input, FLAC__STREAM_METADATA_CUESHEET_RESERVED_LEN))
1765                 return false; /* read_callback_ sets the state for us */
1766
1767         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_NUM_TRACKS_LEN))
1768                 return false; /* read_callback_ sets the state for us */
1769         obj->num_tracks = x;
1770
1771         if(obj->num_tracks > 0) {
1772                 if(0 == (obj->tracks = safe_calloc_(obj->num_tracks, sizeof(FLAC__StreamMetadata_CueSheet_Track)))) {
1773                         decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1774                         return false;
1775                 }
1776                 for(i = 0; i < obj->num_tracks; i++) {
1777                         FLAC__StreamMetadata_CueSheet_Track *track = &obj->tracks[i];
1778                         if(!FLAC__bitreader_read_raw_uint64(decoder->private_->input, &track->offset, FLAC__STREAM_METADATA_CUESHEET_TRACK_OFFSET_LEN))
1779                                 return false; /* read_callback_ sets the state for us */
1780
1781                         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_TRACK_NUMBER_LEN))
1782                                 return false; /* read_callback_ sets the state for us */
1783                         track->number = (FLAC__byte)x;
1784
1785                         FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_TRACK_ISRC_LEN % 8 == 0);
1786                         if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, (FLAC__byte*)track->isrc, FLAC__STREAM_METADATA_CUESHEET_TRACK_ISRC_LEN/8))
1787                                 return false; /* read_callback_ sets the state for us */
1788
1789                         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_TRACK_TYPE_LEN))
1790                                 return false; /* read_callback_ sets the state for us */
1791                         track->type = x;
1792
1793                         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_TRACK_PRE_EMPHASIS_LEN))
1794                                 return false; /* read_callback_ sets the state for us */
1795                         track->pre_emphasis = x;
1796
1797                         if(!FLAC__bitreader_skip_bits_no_crc(decoder->private_->input, FLAC__STREAM_METADATA_CUESHEET_TRACK_RESERVED_LEN))
1798                                 return false; /* read_callback_ sets the state for us */
1799
1800                         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_TRACK_NUM_INDICES_LEN))
1801                                 return false; /* read_callback_ sets the state for us */
1802                         track->num_indices = (FLAC__byte)x;
1803
1804                         if(track->num_indices > 0) {
1805                                 if(0 == (track->indices = safe_calloc_(track->num_indices, sizeof(FLAC__StreamMetadata_CueSheet_Index)))) {
1806                                         decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1807                                         return false;
1808                                 }
1809                                 for(j = 0; j < track->num_indices; j++) {
1810                                         FLAC__StreamMetadata_CueSheet_Index *indx = &track->indices[j];
1811                                         if(!FLAC__bitreader_read_raw_uint64(decoder->private_->input, &indx->offset, FLAC__STREAM_METADATA_CUESHEET_INDEX_OFFSET_LEN))
1812                                                 return false; /* read_callback_ sets the state for us */
1813
1814                                         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_INDEX_NUMBER_LEN))
1815                                                 return false; /* read_callback_ sets the state for us */
1816                                         indx->number = (FLAC__byte)x;
1817
1818                                         if(!FLAC__bitreader_skip_bits_no_crc(decoder->private_->input, FLAC__STREAM_METADATA_CUESHEET_INDEX_RESERVED_LEN))
1819                                                 return false; /* read_callback_ sets the state for us */
1820                                 }
1821                         }
1822                 }
1823         }
1824
1825         return true;
1826 }
1827
1828 FLAC__bool read_metadata_picture_(FLAC__StreamDecoder *decoder, FLAC__StreamMetadata_Picture *obj)
1829 {
1830         FLAC__uint32 x;
1831
1832         FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));
1833
1834         /* read type */
1835         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_PICTURE_TYPE_LEN))
1836                 return false; /* read_callback_ sets the state for us */
1837         obj->type = x;
1838
1839         /* read MIME type */
1840         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_PICTURE_MIME_TYPE_LENGTH_LEN))
1841                 return false; /* read_callback_ sets the state for us */
1842         if(0 == (obj->mime_type = safe_malloc_add_2op_(x, /*+*/1))) {
1843                 decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1844                 return false;
1845         }
1846         if(x > 0) {
1847                 if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, (FLAC__byte*)obj->mime_type, x))
1848                         return false; /* read_callback_ sets the state for us */
1849         }
1850         obj->mime_type[x] = '\0';
1851
1852         /* read description */
1853         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_PICTURE_DESCRIPTION_LENGTH_LEN))
1854                 return false; /* read_callback_ sets the state for us */
1855         if(0 == (obj->description = safe_malloc_add_2op_(x, /*+*/1))) {
1856                 decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1857                 return false;
1858         }
1859         if(x > 0) {
1860                 if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, obj->description, x))
1861                         return false; /* read_callback_ sets the state for us */
1862         }
1863         obj->description[x] = '\0';
1864
1865         /* read width */
1866         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &obj->width, FLAC__STREAM_METADATA_PICTURE_WIDTH_LEN))
1867                 return false; /* read_callback_ sets the state for us */
1868
1869         /* read height */
1870         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &obj->height, FLAC__STREAM_METADATA_PICTURE_HEIGHT_LEN))
1871                 return false; /* read_callback_ sets the state for us */
1872
1873         /* read depth */
1874         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &obj->depth, FLAC__STREAM_METADATA_PICTURE_DEPTH_LEN))
1875                 return false; /* read_callback_ sets the state for us */
1876
1877         /* read colors */
1878         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &obj->colors, FLAC__STREAM_METADATA_PICTURE_COLORS_LEN))
1879                 return false; /* read_callback_ sets the state for us */
1880
1881         /* read data */
1882         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &(obj->data_length), FLAC__STREAM_METADATA_PICTURE_DATA_LENGTH_LEN))
1883                 return false; /* read_callback_ sets the state for us */
1884         if(0 == (obj->data = safe_malloc_(obj->data_length))) {
1885                 decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1886                 return false;
1887         }
1888         if(obj->data_length > 0) {
1889                 if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, obj->data, obj->data_length))
1890                         return false; /* read_callback_ sets the state for us */
1891         }
1892
1893         return true;
1894 }
1895
1896 FLAC__bool skip_id3v2_tag_(FLAC__StreamDecoder *decoder)
1897 {
1898         FLAC__uint32 x;
1899         unsigned i, skip;
1900
1901         /* skip the version and flags bytes */
1902         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 24))
1903                 return false; /* read_callback_ sets the state for us */
1904         /* get the size (in bytes) to skip */
1905         skip = 0;
1906         for(i = 0; i < 4; i++) {
1907                 if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
1908                         return false; /* read_callback_ sets the state for us */
1909                 skip <<= 7;
1910                 skip |= (x & 0x7f);
1911         }
1912         /* skip the rest of the tag */
1913         if(!FLAC__bitreader_skip_byte_block_aligned_no_crc(decoder->private_->input, skip))
1914                 return false; /* read_callback_ sets the state for us */
1915         return true;
1916 }
1917
1918 FLAC__bool frame_sync_(FLAC__StreamDecoder *decoder)
1919 {
1920         FLAC__uint32 x;
1921         FLAC__bool first = true;
1922
1923         /* If we know the total number of samples in the stream, stop if we've read that many. */
1924         /* This will stop us, for example, from wasting time trying to sync on an ID3V1 tag. */
1925         if(FLAC__stream_decoder_get_total_samples(decoder) > 0) {
1926                 if(decoder->private_->samples_decoded >= FLAC__stream_decoder_get_total_samples(decoder)) {
1927                         decoder->protected_->state = FLAC__STREAM_DECODER_END_OF_STREAM;
1928                         return true;
1929                 }
1930         }
1931
1932         /* make sure we're byte aligned */
1933         if(!FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input)) {
1934                 if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__bitreader_bits_left_for_byte_alignment(decoder->private_->input)))
1935                         return false; /* read_callback_ sets the state for us */
1936         }
1937
1938         while(1) {
1939                 if(decoder->private_->cached) {
1940                         x = (FLAC__uint32)decoder->private_->lookahead;
1941                         decoder->private_->cached = false;
1942                 }
1943                 else {
1944                         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
1945                                 return false; /* read_callback_ sets the state for us */
1946                 }
1947                 if(x == 0xff) { /* MAGIC NUMBER for the first 8 frame sync bits */
1948                         decoder->private_->header_warmup[0] = (FLAC__byte)x;
1949                         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
1950                                 return false; /* read_callback_ sets the state for us */
1951
1952                         /* 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 */
1953                         /* else we have to check if the second byte is the end of a sync code */
1954                         if(x == 0xff) { /* MAGIC NUMBER for the first 8 frame sync bits */
1955                                 decoder->private_->lookahead = (FLAC__byte)x;
1956                                 decoder->private_->cached = true;
1957                         }
1958                         else if(x >> 1 == 0x7c) { /* MAGIC NUMBER for the last 6 sync bits and reserved 7th bit */
1959                                 decoder->private_->header_warmup[1] = (FLAC__byte)x;
1960                                 decoder->protected_->state = FLAC__STREAM_DECODER_READ_FRAME;
1961                                 return true;
1962                         }
1963                 }
1964                 if(first) {
1965                         send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
1966                         first = false;
1967                 }
1968         }
1969
1970         return true;
1971 }
1972
1973 FLAC__bool read_frame_(FLAC__StreamDecoder *decoder, FLAC__bool *got_a_frame, FLAC__bool do_full_decode)
1974 {
1975         unsigned channel;
1976         unsigned i;
1977         FLAC__int32 mid, side;
1978         unsigned frame_crc; /* the one we calculate from the input stream */
1979         FLAC__uint32 x;
1980
1981         *got_a_frame = false;
1982
1983         /* init the CRC */
1984         frame_crc = 0;
1985         frame_crc = FLAC__CRC16_UPDATE(decoder->private_->header_warmup[0], frame_crc);
1986         frame_crc = FLAC__CRC16_UPDATE(decoder->private_->header_warmup[1], frame_crc);
1987         FLAC__bitreader_reset_read_crc16(decoder->private_->input, (FLAC__uint16)frame_crc);
1988
1989         if(!read_frame_header_(decoder))
1990                 return false;
1991         if(decoder->protected_->state == FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC) /* means we didn't sync on a valid header */
1992                 return true;
1993         if(!allocate_output_(decoder, decoder->private_->frame.header.blocksize, decoder->private_->frame.header.channels))
1994                 return false;
1995         for(channel = 0; channel < decoder->private_->frame.header.channels; channel++) {
1996                 /*
1997                  * first figure the correct bits-per-sample of the subframe
1998                  */
1999                 unsigned bps = decoder->private_->frame.header.bits_per_sample;
2000                 switch(decoder->private_->frame.header.channel_assignment) {
2001                         case FLAC__CHANNEL_ASSIGNMENT_INDEPENDENT:
2002                                 /* no adjustment needed */
2003                                 break;
2004                         case FLAC__CHANNEL_ASSIGNMENT_LEFT_SIDE:
2005                                 FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
2006                                 if(channel == 1)
2007                                         bps++;
2008                                 break;
2009                         case FLAC__CHANNEL_ASSIGNMENT_RIGHT_SIDE:
2010                                 FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
2011                                 if(channel == 0)
2012                                         bps++;
2013                                 break;
2014                         case FLAC__CHANNEL_ASSIGNMENT_MID_SIDE:
2015                                 FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
2016                                 if(channel == 1)
2017                                         bps++;
2018                                 break;
2019                         default:
2020                                 FLAC__ASSERT(0);
2021                 }
2022                 /*
2023                  * now read it
2024                  */
2025                 if(!read_subframe_(decoder, channel, bps, do_full_decode))
2026                         return false;
2027                 if(decoder->protected_->state == FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC) /* means bad sync or got corruption */
2028                         return true;
2029         }
2030         if(!read_zero_padding_(decoder))
2031                 return false;
2032         if(decoder->protected_->state == FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC) /* means bad sync or got corruption (i.e. "zero bits" were not all zeroes) */
2033                 return true;
2034
2035         /*
2036          * Read the frame CRC-16 from the footer and check
2037          */
2038         frame_crc = FLAC__bitreader_get_read_crc16(decoder->private_->input);
2039         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__FRAME_FOOTER_CRC_LEN))
2040                 return false; /* read_callback_ sets the state for us */
2041         if(frame_crc == x) {
2042                 if(do_full_decode) {
2043                         /* Undo any special channel coding */
2044                         switch(decoder->private_->frame.header.channel_assignment) {
2045                                 case FLAC__CHANNEL_ASSIGNMENT_INDEPENDENT:
2046                                         /* do nothing */
2047                                         break;
2048                                 case FLAC__CHANNEL_ASSIGNMENT_LEFT_SIDE:
2049                                         FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
2050                                         for(i = 0; i < decoder->private_->frame.header.blocksize; i++)
2051                                                 decoder->private_->output[1][i] = decoder->private_->output[0][i] - decoder->private_->output[1][i];
2052                                         break;
2053                                 case FLAC__CHANNEL_ASSIGNMENT_RIGHT_SIDE:
2054                                         FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
2055                                         for(i = 0; i < decoder->private_->frame.header.blocksize; i++)
2056                                                 decoder->private_->output[0][i] += decoder->private_->output[1][i];
2057                                         break;
2058                                 case FLAC__CHANNEL_ASSIGNMENT_MID_SIDE:
2059                                         FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
2060                                         for(i = 0; i < decoder->private_->frame.header.blocksize; i++) {
2061 #if 1
2062                                                 mid = decoder->private_->output[0][i];
2063                                                 side = decoder->private_->output[1][i];
2064                                                 mid <<= 1;
2065                                                 mid |= (side & 1); /* i.e. if 'side' is odd... */
2066                                                 decoder->private_->output[0][i] = (mid + side) >> 1;
2067                                                 decoder->private_->output[1][i] = (mid - side) >> 1;
2068 #else
2069                                                 /* OPT: without 'side' temp variable */
2070                                                 mid = (decoder->private_->output[0][i] << 1) | (decoder->private_->output[1][i] & 1); /* i.e. if 'side' is odd... */
2071                                                 decoder->private_->output[0][i] = (mid + decoder->private_->output[1][i]) >> 1;
2072                                                 decoder->private_->output[1][i] = (mid - decoder->private_->output[1][i]) >> 1;
2073 #endif
2074                                         }
2075                                         break;
2076                                 default:
2077                                         FLAC__ASSERT(0);
2078                                         break;
2079                         }
2080                 }
2081         }
2082         else {
2083                 /* Bad frame, emit error and zero the output signal */
2084                 send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_FRAME_CRC_MISMATCH);
2085                 if(do_full_decode) {
2086                         for(channel = 0; channel < decoder->private_->frame.header.channels; channel++) {
2087                                 memset(decoder->private_->output[channel], 0, sizeof(FLAC__int32) * decoder->private_->frame.header.blocksize);
2088                         }
2089                 }
2090         }
2091
2092         *got_a_frame = true;
2093
2094         /* we wait to update fixed_block_size until here, when we're sure we've got a proper frame and hence a correct blocksize */
2095         if(decoder->private_->next_fixed_block_size)
2096                 decoder->private_->fixed_block_size = decoder->private_->next_fixed_block_size;
2097
2098         /* put the latest values into the public section of the decoder instance */
2099         decoder->protected_->channels = decoder->private_->frame.header.channels;
2100         decoder->protected_->channel_assignment = decoder->private_->frame.header.channel_assignment;
2101         decoder->protected_->bits_per_sample = decoder->private_->frame.header.bits_per_sample;
2102         decoder->protected_->sample_rate = decoder->private_->frame.header.sample_rate;
2103         decoder->protected_->blocksize = decoder->private_->frame.header.blocksize;
2104
2105         FLAC__ASSERT(decoder->private_->frame.header.number_type == FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER);
2106         decoder->private_->samples_decoded = decoder->private_->frame.header.number.sample_number + decoder->private_->frame.header.blocksize;
2107
2108         /* write it */
2109         if(do_full_decode) {
2110                 if(write_audio_frame_to_client_(decoder, &decoder->private_->frame, (const FLAC__int32 * const *)decoder->private_->output) != FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE)
2111                         return false;
2112         }
2113
2114         decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2115         return true;
2116 }
2117
2118 FLAC__bool read_frame_header_(FLAC__StreamDecoder *decoder)
2119 {
2120         FLAC__uint32 x;
2121         FLAC__uint64 xx;
2122         unsigned i, blocksize_hint = 0, sample_rate_hint = 0;
2123         FLAC__byte crc8, raw_header[16]; /* MAGIC NUMBER based on the maximum frame header size, including CRC */
2124         unsigned raw_header_len;
2125         FLAC__bool is_unparseable = false;
2126
2127         FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));
2128
2129         /* init the raw header with the saved bits from synchronization */
2130         raw_header[0] = decoder->private_->header_warmup[0];
2131         raw_header[1] = decoder->private_->header_warmup[1];
2132         raw_header_len = 2;
2133
2134         /* check to make sure that reserved bit is 0 */
2135         if(raw_header[1] & 0x02) /* MAGIC NUMBER */
2136                 is_unparseable = true;
2137
2138         /*
2139          * Note that along the way as we read the header, we look for a sync
2140          * code inside.  If we find one it would indicate that our original
2141          * sync was bad since there cannot be a sync code in a valid header.
2142          *
2143          * Three kinds of things can go wrong when reading the frame header:
2144          *  1) We may have sync'ed incorrectly and not landed on a frame header.
2145          *     If we don't find a sync code, it can end up looking like we read
2146          *     a valid but unparseable header, until getting to the frame header
2147          *     CRC.  Even then we could get a false positive on the CRC.
2148          *  2) We may have sync'ed correctly but on an unparseable frame (from a
2149          *     future encoder).
2150          *  3) We may be on a damaged frame which appears valid but unparseable.
2151          *
2152          * For all these reasons, we try and read a complete frame header as
2153          * long as it seems valid, even if unparseable, up until the frame
2154          * header CRC.
2155          */
2156
2157         /*
2158          * read in the raw header as bytes so we can CRC it, and parse it on the way
2159          */
2160         for(i = 0; i < 2; i++) {
2161                 if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
2162                         return false; /* read_callback_ sets the state for us */
2163                 if(x == 0xff) { /* MAGIC NUMBER for the first 8 frame sync bits */
2164                         /* if we get here it means our original sync was erroneous since the sync code cannot appear in the header */
2165                         decoder->private_->lookahead = (FLAC__byte)x;
2166                         decoder->private_->cached = true;
2167                         send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER);
2168                         decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2169                         return true;
2170                 }
2171                 raw_header[raw_header_len++] = (FLAC__byte)x;
2172         }
2173
2174         switch(x = raw_header[2] >> 4) {
2175                 case 0:
2176                         is_unparseable = true;
2177                         break;
2178                 case 1:
2179                         decoder->private_->frame.header.blocksize = 192;
2180                         break;
2181                 case 2:
2182                 case 3:
2183                 case 4:
2184                 case 5:
2185                         decoder->private_->frame.header.blocksize = 576 << (x-2);
2186                         break;
2187                 case 6:
2188                 case 7:
2189                         blocksize_hint = x;
2190                         break;
2191                 case 8:
2192                 case 9:
2193                 case 10:
2194                 case 11:
2195                 case 12:
2196                 case 13:
2197                 case 14:
2198                 case 15:
2199                         decoder->private_->frame.header.blocksize = 256 << (x-8);
2200                         break;
2201                 default:
2202                         FLAC__ASSERT(0);
2203                         break;
2204         }
2205
2206         switch(x = raw_header[2] & 0x0f) {
2207                 case 0:
2208                         if(decoder->private_->has_stream_info)
2209                                 decoder->private_->frame.header.sample_rate = decoder->private_->stream_info.data.stream_info.sample_rate;
2210                         else
2211                                 is_unparseable = true;
2212                         break;
2213                 case 1:
2214                         decoder->private_->frame.header.sample_rate = 88200;
2215                         break;
2216                 case 2:
2217                         decoder->private_->frame.header.sample_rate = 176400;
2218                         break;
2219                 case 3:
2220                         decoder->private_->frame.header.sample_rate = 192000;
2221                         break;
2222                 case 4:
2223                         decoder->private_->frame.header.sample_rate = 8000;
2224                         break;
2225                 case 5:
2226                         decoder->private_->frame.header.sample_rate = 16000;
2227                         break;
2228                 case 6:
2229                         decoder->private_->frame.header.sample_rate = 22050;
2230                         break;
2231                 case 7:
2232                         decoder->private_->frame.header.sample_rate = 24000;
2233                         break;
2234                 case 8:
2235                         decoder->private_->frame.header.sample_rate = 32000;
2236                         break;
2237                 case 9:
2238                         decoder->private_->frame.header.sample_rate = 44100;
2239                         break;
2240                 case 10:
2241                         decoder->private_->frame.header.sample_rate = 48000;
2242                         break;
2243                 case 11:
2244                         decoder->private_->frame.header.sample_rate = 96000;
2245                         break;
2246                 case 12:
2247                 case 13:
2248                 case 14:
2249                         sample_rate_hint = x;
2250                         break;
2251                 case 15:
2252                         send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER);
2253                         decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2254                         return true;
2255                 default:
2256                         FLAC__ASSERT(0);
2257         }
2258
2259         x = (unsigned)(raw_header[3] >> 4);
2260         if(x & 8) {
2261                 decoder->private_->frame.header.channels = 2;
2262                 switch(x & 7) {
2263                         case 0:
2264                                 decoder->private_->frame.header.channel_assignment = FLAC__CHANNEL_ASSIGNMENT_LEFT_SIDE;
2265                                 break;
2266                         case 1:
2267                                 decoder->private_->frame.header.channel_assignment = FLAC__CHANNEL_ASSIGNMENT_RIGHT_SIDE;
2268                                 break;
2269                         case 2:
2270                                 decoder->private_->frame.header.channel_assignment = FLAC__CHANNEL_ASSIGNMENT_MID_SIDE;
2271                                 break;
2272                         default:
2273                                 is_unparseable = true;
2274                                 break;
2275                 }
2276         }
2277         else {
2278                 decoder->private_->frame.header.channels = (unsigned)x + 1;
2279                 decoder->private_->frame.header.channel_assignment = FLAC__CHANNEL_ASSIGNMENT_INDEPENDENT;
2280         }
2281
2282         switch(x = (unsigned)(raw_header[3] & 0x0e) >> 1) {
2283                 case 0:
2284                         if(decoder->private_->has_stream_info)
2285                                 decoder->private_->frame.header.bits_per_sample = decoder->private_->stream_info.data.stream_info.bits_per_sample;
2286                         else
2287                                 is_unparseable = true;
2288                         break;
2289                 case 1:
2290                         decoder->private_->frame.header.bits_per_sample = 8;
2291                         break;
2292                 case 2:
2293                         decoder->private_->frame.header.bits_per_sample = 12;
2294                         break;
2295                 case 4:
2296                         decoder->private_->frame.header.bits_per_sample = 16;
2297                         break;
2298                 case 5:
2299                         decoder->private_->frame.header.bits_per_sample = 20;
2300                         break;
2301                 case 6:
2302                         decoder->private_->frame.header.bits_per_sample = 24;
2303                         break;
2304                 case 3:
2305                 case 7:
2306                         is_unparseable = true;
2307                         break;
2308                 default:
2309                         FLAC__ASSERT(0);
2310                         break;
2311         }
2312
2313         /* check to make sure that reserved bit is 0 */
2314         if(raw_header[3] & 0x01) /* MAGIC NUMBER */
2315                 is_unparseable = true;
2316
2317         /* read the frame's starting sample number (or frame number as the case may be) */
2318         if(
2319                 raw_header[1] & 0x01 ||
2320                 /*@@@ this clause is a concession to the old way of doing variable blocksize; the only known implementation is flake and can probably be removed without inconveniencing anyone */
2321                 (decoder->private_->has_stream_info && decoder->private_->stream_info.data.stream_info.min_blocksize != decoder->private_->stream_info.data.stream_info.max_blocksize)
2322         ) { /* variable blocksize */
2323                 if(!FLAC__bitreader_read_utf8_uint64(decoder->private_->input, &xx, raw_header, &raw_header_len))
2324                         return false; /* read_callback_ sets the state for us */
2325                 if(xx == FLAC__U64L(0xffffffffffffffff)) { /* i.e. non-UTF8 code... */
2326                         decoder->private_->lookahead = raw_header[raw_header_len-1]; /* back up as much as we can */
2327                         decoder->private_->cached = true;
2328                         send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER);
2329                         decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2330                         return true;
2331                 }
2332                 decoder->private_->frame.header.number_type = FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER;
2333                 decoder->private_->frame.header.number.sample_number = xx;
2334         }
2335         else { /* fixed blocksize */
2336                 if(!FLAC__bitreader_read_utf8_uint32(decoder->private_->input, &x, raw_header, &raw_header_len))
2337                         return false; /* read_callback_ sets the state for us */
2338                 if(x == 0xffffffff) { /* i.e. non-UTF8 code... */
2339                         decoder->private_->lookahead = raw_header[raw_header_len-1]; /* back up as much as we can */
2340                         decoder->private_->cached = true;
2341                         send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER);
2342                         decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2343                         return true;
2344                 }
2345                 decoder->private_->frame.header.number_type = FLAC__FRAME_NUMBER_TYPE_FRAME_NUMBER;
2346                 decoder->private_->frame.header.number.frame_number = x;
2347         }
2348
2349         if(blocksize_hint) {
2350                 if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
2351                         return false; /* read_callback_ sets the state for us */
2352                 raw_header[raw_header_len++] = (FLAC__byte)x;
2353                 if(blocksize_hint == 7) {
2354                         FLAC__uint32 _x;
2355                         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &_x, 8))
2356                                 return false; /* read_callback_ sets the state for us */
2357                         raw_header[raw_header_len++] = (FLAC__byte)_x;
2358                         x = (x << 8) | _x;
2359                 }
2360                 decoder->private_->frame.header.blocksize = x+1;
2361         }
2362
2363         if(sample_rate_hint) {
2364                 if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
2365                         return false; /* read_callback_ sets the state for us */
2366                 raw_header[raw_header_len++] = (FLAC__byte)x;
2367                 if(sample_rate_hint != 12) {
2368                         FLAC__uint32 _x;
2369                         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &_x, 8))
2370                                 return false; /* read_callback_ sets the state for us */
2371                         raw_header[raw_header_len++] = (FLAC__byte)_x;
2372                         x = (x << 8) | _x;
2373                 }
2374                 if(sample_rate_hint == 12)
2375                         decoder->private_->frame.header.sample_rate = x*1000;
2376                 else if(sample_rate_hint == 13)
2377                         decoder->private_->frame.header.sample_rate = x;
2378                 else
2379                         decoder->private_->frame.header.sample_rate = x*10;
2380         }
2381
2382         /* read the CRC-8 byte */
2383         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
2384                 return false; /* read_callback_ sets the state for us */
2385         crc8 = (FLAC__byte)x;
2386
2387         if(FLAC__crc8(raw_header, raw_header_len) != crc8) {
2388                 send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER);
2389                 decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2390                 return true;
2391         }
2392
2393         /* calculate the sample number from the frame number if needed */
2394         decoder->private_->next_fixed_block_size = 0;
2395         if(decoder->private_->frame.header.number_type == FLAC__FRAME_NUMBER_TYPE_FRAME_NUMBER) {
2396                 x = decoder->private_->frame.header.number.frame_number;
2397                 decoder->private_->frame.header.number_type = FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER;
2398                 if(decoder->private_->fixed_block_size)
2399                         decoder->private_->frame.header.number.sample_number = (FLAC__uint64)decoder->private_->fixed_block_size * (FLAC__uint64)x;
2400                 else if(decoder->private_->has_stream_info) {
2401                         if(decoder->private_->stream_info.data.stream_info.min_blocksize == decoder->private_->stream_info.data.stream_info.max_blocksize) {
2402                                 decoder->private_->frame.header.number.sample_number = (FLAC__uint64)decoder->private_->stream_info.data.stream_info.min_blocksize * (FLAC__uint64)x;
2403                                 decoder->private_->next_fixed_block_size = decoder->private_->stream_info.data.stream_info.max_blocksize;
2404                         }
2405                         else
2406                                 is_unparseable = true;
2407                 }
2408                 else if(x == 0) {
2409                         decoder->private_->frame.header.number.sample_number = 0;
2410                         decoder->private_->next_fixed_block_size = decoder->private_->frame.header.blocksize;
2411                 }
2412                 else {
2413                         /* can only get here if the stream has invalid frame numbering and no STREAMINFO, so assume it's not the last (possibly short) frame */
2414                         decoder->private_->frame.header.number.sample_number = (FLAC__uint64)decoder->private_->frame.header.blocksize * (FLAC__uint64)x;
2415                 }
2416         }
2417
2418         if(is_unparseable) {
2419                 send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM);
2420                 decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2421                 return true;
2422         }
2423
2424         return true;
2425 }
2426
2427 FLAC__bool read_subframe_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, FLAC__bool do_full_decode)
2428 {
2429         FLAC__uint32 x;
2430         FLAC__bool wasted_bits;
2431         unsigned i;
2432
2433         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8)) /* MAGIC NUMBER */
2434                 return false; /* read_callback_ sets the state for us */
2435
2436         wasted_bits = (x & 1);
2437         x &= 0xfe;
2438
2439         if(wasted_bits) {
2440                 unsigned u;
2441                 if(!FLAC__bitreader_read_unary_unsigned(decoder->private_->input, &u))
2442                         return false; /* read_callback_ sets the state for us */
2443                 decoder->private_->frame.subframes[channel].wasted_bits = u+1;
2444                 bps -= decoder->private_->frame.subframes[channel].wasted_bits;
2445         }
2446         else
2447                 decoder->private_->frame.subframes[channel].wasted_bits = 0;
2448
2449         /*
2450          * Lots of magic numbers here
2451          */
2452         if(x & 0x80) {
2453                 send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
2454                 decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2455                 return true;
2456         }
2457         else if(x == 0) {
2458                 if(!read_subframe_constant_(decoder, channel, bps, do_full_decode))
2459                         return false;
2460         }
2461         else if(x == 2) {
2462                 if(!read_subframe_verbatim_(decoder, channel, bps, do_full_decode))
2463                         return false;
2464         }
2465         else if(x < 16) {
2466                 send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM);
2467                 decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2468                 return true;
2469         }
2470         else if(x <= 24) {
2471                 if(!read_subframe_fixed_(decoder, channel, bps, (x>>1)&7, do_full_decode))
2472                         return false;
2473                 if(decoder->protected_->state == FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC) /* means bad sync or got corruption */
2474                         return true;
2475         }
2476         else if(x < 64) {
2477                 send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM);
2478                 decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2479                 return true;
2480         }
2481         else {
2482                 if(!read_subframe_lpc_(decoder, channel, bps, ((x>>1)&31)+1, do_full_decode))
2483                         return false;
2484                 if(decoder->protected_->state == FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC) /* means bad sync or got corruption */
2485                         return true;
2486         }
2487
2488         if(wasted_bits && do_full_decode) {
2489                 x = decoder->private_->frame.subframes[channel].wasted_bits;
2490                 for(i = 0; i < decoder->private_->frame.header.blocksize; i++)
2491                         decoder->private_->output[channel][i] <<= x;
2492         }
2493
2494         return true;
2495 }
2496
2497 FLAC__bool read_subframe_constant_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, FLAC__bool do_full_decode)
2498 {
2499         FLAC__Subframe_Constant *subframe = &decoder->private_->frame.subframes[channel].data.constant;
2500         FLAC__int32 x;
2501         unsigned i;
2502         FLAC__int32 *output = decoder->private_->output[channel];
2503
2504         decoder->private_->frame.subframes[channel].type = FLAC__SUBFRAME_TYPE_CONSTANT;
2505
2506         if(!FLAC__bitreader_read_raw_int32(decoder->private_->input, &x, bps))
2507                 return false; /* read_callback_ sets the state for us */
2508
2509         subframe->value = x;
2510
2511         /* decode the subframe */
2512         if(do_full_decode) {
2513                 for(i = 0; i < decoder->private_->frame.header.blocksize; i++)
2514                         output[i] = x;
2515         }
2516
2517         return true;
2518 }
2519
2520 FLAC__bool read_subframe_fixed_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, const unsigned order, FLAC__bool do_full_decode)
2521 {
2522         FLAC__Subframe_Fixed *subframe = &decoder->private_->frame.subframes[channel].data.fixed;
2523         FLAC__int32 i32;
2524         FLAC__uint32 u32;
2525         unsigned u;
2526
2527         decoder->private_->frame.subframes[channel].type = FLAC__SUBFRAME_TYPE_FIXED;
2528
2529         subframe->residual = decoder->private_->residual[channel];
2530         subframe->order = order;
2531
2532         /* read warm-up samples */
2533         for(u = 0; u < order; u++) {
2534                 if(!FLAC__bitreader_read_raw_int32(decoder->private_->input, &i32, bps))
2535                         return false; /* read_callback_ sets the state for us */
2536                 subframe->warmup[u] = i32;
2537         }
2538
2539         /* read entropy coding method info */
2540         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &u32, FLAC__ENTROPY_CODING_METHOD_TYPE_LEN))
2541                 return false; /* read_callback_ sets the state for us */
2542         subframe->entropy_coding_method.type = (FLAC__EntropyCodingMethodType)u32;
2543         switch(subframe->entropy_coding_method.type) {
2544                 case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE:
2545                 case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2:
2546                         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &u32, FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_ORDER_LEN))
2547                                 return false; /* read_callback_ sets the state for us */
2548                         subframe->entropy_coding_method.data.partitioned_rice.order = u32;
2549                         subframe->entropy_coding_method.data.partitioned_rice.contents = &decoder->private_->partitioned_rice_contents[channel];
2550                         break;
2551                 default:
2552                         send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM);
2553                         decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2554                         return true;
2555         }
2556
2557         /* read residual */
2558         switch(subframe->entropy_coding_method.type) {
2559                 case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE:
2560                 case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2:
2561                         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], /*is_extended=*/subframe->entropy_coding_method.type == FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2))
2562                                 return false;
2563                         break;
2564                 default:
2565                         FLAC__ASSERT(0);
2566         }
2567
2568         /* decode the subframe */
2569         if(do_full_decode) {
2570                 memcpy(decoder->private_->output[channel], subframe->warmup, sizeof(FLAC__int32) * order);
2571                 FLAC__fixed_restore_signal(decoder->private_->residual[channel], decoder->private_->frame.header.blocksize-order, order, decoder->private_->output[channel]+order);
2572         }
2573
2574         return true;
2575 }
2576
2577 FLAC__bool read_subframe_lpc_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, const unsigned order, FLAC__bool do_full_decode)
2578 {
2579         FLAC__Subframe_LPC *subframe = &decoder->private_->frame.subframes[channel].data.lpc;
2580         FLAC__int32 i32;
2581         FLAC__uint32 u32;
2582         unsigned u;
2583
2584         decoder->private_->frame.subframes[channel].type = FLAC__SUBFRAME_TYPE_LPC;
2585
2586         subframe->residual = decoder->private_->residual[channel];
2587         subframe->order = order;
2588
2589         /* read warm-up samples */
2590         for(u = 0; u < order; u++) {
2591                 if(!FLAC__bitreader_read_raw_int32(decoder->private_->input, &i32, bps))
2592                         return false; /* read_callback_ sets the state for us */
2593                 subframe->warmup[u] = i32;
2594         }
2595
2596         /* read qlp coeff precision */
2597         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &u32, FLAC__SUBFRAME_LPC_QLP_COEFF_PRECISION_LEN))
2598                 return false; /* read_callback_ sets the state for us */
2599         if(u32 == (1u << FLAC__SUBFRAME_LPC_QLP_COEFF_PRECISION_LEN) - 1) {
2600                 send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
2601                 decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2602                 return true;
2603         }
2604         subframe->qlp_coeff_precision = u32+1;
2605
2606         /* read qlp shift */
2607         if(!FLAC__bitreader_read_raw_int32(decoder->private_->input, &i32, FLAC__SUBFRAME_LPC_QLP_SHIFT_LEN))
2608                 return false; /* read_callback_ sets the state for us */
2609         subframe->quantization_level = i32;
2610
2611         /* read quantized lp coefficiencts */
2612         for(u = 0; u < order; u++) {
2613                 if(!FLAC__bitreader_read_raw_int32(decoder->private_->input, &i32, subframe->qlp_coeff_precision))
2614                         return false; /* read_callback_ sets the state for us */
2615                 subframe->qlp_coeff[u] = i32;
2616         }
2617
2618         /* read entropy coding method info */
2619         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &u32, FLAC__ENTROPY_CODING_METHOD_TYPE_LEN))
2620                 return false; /* read_callback_ sets the state for us */
2621         subframe->entropy_coding_method.type = (FLAC__EntropyCodingMethodType)u32;
2622         switch(subframe->entropy_coding_method.type) {
2623                 case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE:
2624                 case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2:
2625                         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &u32, FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_ORDER_LEN))
2626                                 return false; /* read_callback_ sets the state for us */
2627                         subframe->entropy_coding_method.data.partitioned_rice.order = u32;
2628                         subframe->entropy_coding_method.data.partitioned_rice.contents = &decoder->private_->partitioned_rice_contents[channel];
2629                         break;
2630                 default:
2631                         send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM);
2632                         decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2633                         return true;
2634         }
2635
2636         /* read residual */
2637         switch(subframe->entropy_coding_method.type) {
2638                 case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE:
2639                 case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2:
2640                         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], /*is_extended=*/subframe->entropy_coding_method.type == FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2))
2641                                 return false;
2642                         break;
2643                 default:
2644                         FLAC__ASSERT(0);
2645         }
2646
2647         /* decode the subframe */
2648         if(do_full_decode) {
2649                 memcpy(decoder->private_->output[channel], subframe->warmup, sizeof(FLAC__int32) * order);
2650                 /*@@@@@@ technically not pessimistic enough, should be more like
2651                 if( (FLAC__uint64)order * ((((FLAC__uint64)1)<<bps)-1) * ((1<<subframe->qlp_coeff_precision)-1) < (((FLAC__uint64)-1) << 32) )
2652                 */
2653                 if(bps + subframe->qlp_coeff_precision + FLAC__bitmath_ilog2(order) <= 32)
2654                         if(bps <= 16 && subframe->qlp_coeff_precision <= 16) {
2655                                 if(order <= 8)
2656                                         decoder->private_->local_lpc_restore_signal_16bit_order8(decoder->private_->residual[channel], decoder->private_->frame.header.blocksize-order, subframe->qlp_coeff, order, subframe->quantization_level, decoder->private_->output[channel]+order);
2657                                 else
2658                                         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);
2659                         }
2660                         else
2661                                 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);
2662                 else
2663                         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);
2664         }
2665
2666         return true;
2667 }
2668
2669 FLAC__bool read_subframe_verbatim_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, FLAC__bool do_full_decode)
2670 {
2671         FLAC__Subframe_Verbatim *subframe = &decoder->private_->frame.subframes[channel].data.verbatim;
2672         FLAC__int32 x, *residual = decoder->private_->residual[channel];
2673         unsigned i;
2674
2675         decoder->private_->frame.subframes[channel].type = FLAC__SUBFRAME_TYPE_VERBATIM;
2676
2677         subframe->data = residual;
2678
2679         for(i = 0; i < decoder->private_->frame.header.blocksize; i++) {
2680                 if(!FLAC__bitreader_read_raw_int32(decoder->private_->input, &x, bps))
2681                         return false; /* read_callback_ sets the state for us */
2682                 residual[i] = x;
2683         }
2684
2685         /* decode the subframe */
2686         if(do_full_decode)
2687                 memcpy(decoder->private_->output[channel], subframe->data, sizeof(FLAC__int32) * decoder->private_->frame.header.blocksize);
2688
2689         return true;
2690 }
2691
2692 FLAC__bool read_residual_partitioned_rice_(FLAC__StreamDecoder *decoder, unsigned predictor_order, unsigned partition_order, FLAC__EntropyCodingMethod_PartitionedRiceContents *partitioned_rice_contents, FLAC__int32 *residual, FLAC__bool is_extended)
2693 {
2694         FLAC__uint32 rice_parameter;
2695         int i;
2696         unsigned partition, sample, u;
2697         const unsigned partitions = 1u << partition_order;
2698         const unsigned partition_samples = partition_order > 0? decoder->private_->frame.header.blocksize >> partition_order : decoder->private_->frame.header.blocksize - predictor_order;
2699         const unsigned plen = is_extended? FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2_PARAMETER_LEN : FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_PARAMETER_LEN;
2700         const unsigned pesc = is_extended? FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2_ESCAPE_PARAMETER : FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_ESCAPE_PARAMETER;
2701
2702         /* sanity checks */
2703         if(partition_order == 0) {
2704                 if(decoder->private_->frame.header.blocksize < predictor_order) {
2705                         send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
2706                         decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2707                         return true;
2708                 }
2709         }
2710         else {
2711                 if(partition_samples < predictor_order) {
2712                         send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
2713                         decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2714                         return true;
2715                 }
2716         }
2717
2718         if(!FLAC__format_entropy_coding_method_partitioned_rice_contents_ensure_size(partitioned_rice_contents, flac_max(6u, partition_order))) {
2719                 decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
2720                 return false;
2721         }
2722
2723         sample = 0;
2724         for(partition = 0; partition < partitions; partition++) {
2725                 if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &rice_parameter, plen))
2726                         return false; /* read_callback_ sets the state for us */
2727                 partitioned_rice_contents->parameters[partition] = rice_parameter;
2728                 if(rice_parameter < pesc) {
2729                         partitioned_rice_contents->raw_bits[partition] = 0;
2730                         u = (partition_order == 0 || partition > 0)? partition_samples : partition_samples - predictor_order;
2731                         if(!decoder->private_->local_bitreader_read_rice_signed_block(decoder->private_->input, residual + sample, u, rice_parameter))
2732                                 return false; /* read_callback_ sets the state for us */
2733                         sample += u;
2734                 }
2735                 else {
2736                         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &rice_parameter, FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_RAW_LEN))
2737                                 return false; /* read_callback_ sets the state for us */
2738                         partitioned_rice_contents->raw_bits[partition] = rice_parameter;
2739                         for(u = (partition_order == 0 || partition > 0)? 0 : predictor_order; u < partition_samples; u++, sample++) {
2740                                 if(!FLAC__bitreader_read_raw_int32(decoder->private_->input, &i, rice_parameter))
2741                                         return false; /* read_callback_ sets the state for us */
2742                                 residual[sample] = i;
2743                         }
2744                 }
2745         }
2746
2747         return true;
2748 }
2749
2750 FLAC__bool read_zero_padding_(FLAC__StreamDecoder *decoder)
2751 {
2752         if(!FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input)) {
2753                 FLAC__uint32 zero = 0;
2754                 if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &zero, FLAC__bitreader_bits_left_for_byte_alignment(decoder->private_->input)))
2755                         return false; /* read_callback_ sets the state for us */
2756                 if(zero != 0) {
2757                         send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
2758                         decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2759                 }
2760         }
2761         return true;
2762 }
2763
2764 FLAC__bool read_callback_(FLAC__byte buffer[], size_t *bytes, void *client_data)
2765 {
2766         FLAC__StreamDecoder *decoder = (FLAC__StreamDecoder *)client_data;
2767
2768         if(
2769 #if FLAC__HAS_OGG
2770                 /* see [1] HACK NOTE below for why we don't call the eof_callback when decoding Ogg FLAC */
2771                 !decoder->private_->is_ogg &&
2772 #endif
2773                 decoder->private_->eof_callback && decoder->private_->eof_callback(decoder, decoder->private_->client_data)
2774         ) {
2775                 *bytes = 0;
2776                 decoder->protected_->state = FLAC__STREAM_DECODER_END_OF_STREAM;
2777                 return false;
2778         }
2779         else if(*bytes > 0) {
2780                 /* While seeking, it is possible for our seek to land in the
2781                  * middle of audio data that looks exactly like a frame header
2782                  * from a future version of an encoder.  When that happens, our
2783                  * error callback will get an
2784                  * FLAC__STREAM_DECODER_UNPARSEABLE_STREAM and increment its
2785                  * unparseable_frame_count.  But there is a remote possibility
2786                  * that it is properly synced at such a "future-codec frame",
2787                  * so to make sure, we wait to see many "unparseable" errors in
2788                  * a row before bailing out.
2789                  */
2790                 if(decoder->private_->is_seeking && decoder->private_->unparseable_frame_count > 20) {
2791                         decoder->protected_->state = FLAC__STREAM_DECODER_ABORTED;
2792                         return false;
2793                 }
2794                 else {
2795                         const FLAC__StreamDecoderReadStatus status =
2796 #if FLAC__HAS_OGG
2797                                 decoder->private_->is_ogg?
2798                                 read_callback_ogg_aspect_(decoder, buffer, bytes) :
2799 #endif
2800                                 decoder->private_->read_callback(decoder, buffer, bytes, decoder->private_->client_data)
2801                         ;
2802                         if(status == FLAC__STREAM_DECODER_READ_STATUS_ABORT) {
2803                                 decoder->protected_->state = FLAC__STREAM_DECODER_ABORTED;
2804                                 return false;
2805                         }
2806                         else if(*bytes == 0) {
2807                                 if(
2808                                         status == FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM ||
2809                                         (
2810 #if FLAC__HAS_OGG
2811                                                 /* see [1] HACK NOTE below for why we don't call the eof_callback when decoding Ogg FLAC */
2812                                                 !decoder->private_->is_ogg &&
2813 #endif
2814                                                 decoder->private_->eof_callback && decoder->private_->eof_callback(decoder, decoder->private_->client_data)
2815                                         )
2816                                 ) {
2817                                         decoder->protected_->state = FLAC__STREAM_DECODER_END_OF_STREAM;
2818                                         return false;
2819                                 }
2820                                 else
2821                                         return true;
2822                         }
2823                         else
2824                                 return true;
2825                 }
2826         }
2827         else {
2828                 /* abort to avoid a deadlock */
2829                 decoder->protected_->state = FLAC__STREAM_DECODER_ABORTED;
2830                 return false;
2831         }
2832         /* [1] @@@ HACK NOTE: The end-of-stream checking has to be hacked around
2833          * for Ogg FLAC.  This is because the ogg decoder aspect can lose sync
2834          * and at the same time hit the end of the stream (for example, seeking
2835          * to a point that is after the beginning of the last Ogg page).  There
2836          * is no way to report an Ogg sync loss through the callbacks (see note
2837          * in read_callback_ogg_aspect_()) so it returns CONTINUE with *bytes==0.
2838          * So to keep the decoder from stopping at this point we gate the call
2839          * to the eof_callback and let the Ogg decoder aspect set the
2840          * end-of-stream state when it is needed.
2841          */
2842 }
2843
2844 #if FLAC__HAS_OGG
2845 FLAC__StreamDecoderReadStatus read_callback_ogg_aspect_(const FLAC__StreamDecoder *decoder, FLAC__byte buffer[], size_t *bytes)
2846 {
2847         switch(FLAC__ogg_decoder_aspect_read_callback_wrapper(&decoder->protected_->ogg_decoder_aspect, buffer, bytes, read_callback_proxy_, decoder, decoder->private_->client_data)) {
2848                 case FLAC__OGG_DECODER_ASPECT_READ_STATUS_OK:
2849                         return FLAC__STREAM_DECODER_READ_STATUS_CONTINUE;
2850                 /* we don't really have a way to handle lost sync via read
2851                  * callback so we'll let it pass and let the underlying
2852                  * FLAC decoder catch the error
2853                  */
2854                 case FLAC__OGG_DECODER_ASPECT_READ_STATUS_LOST_SYNC:
2855                         return FLAC__STREAM_DECODER_READ_STATUS_CONTINUE;
2856                 case FLAC__OGG_DECODER_ASPECT_READ_STATUS_END_OF_STREAM:
2857                         return FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM;
2858                 case FLAC__OGG_DECODER_ASPECT_READ_STATUS_NOT_FLAC:
2859                 case FLAC__OGG_DECODER_ASPECT_READ_STATUS_UNSUPPORTED_MAPPING_VERSION:
2860                 case FLAC__OGG_DECODER_ASPECT_READ_STATUS_ABORT:
2861                 case FLAC__OGG_DECODER_ASPECT_READ_STATUS_ERROR:
2862                 case FLAC__OGG_DECODER_ASPECT_READ_STATUS_MEMORY_ALLOCATION_ERROR:
2863                         return FLAC__STREAM_DECODER_READ_STATUS_ABORT;
2864                 default:
2865                         FLAC__ASSERT(0);
2866                         /* double protection */
2867                         return FLAC__STREAM_DECODER_READ_STATUS_ABORT;
2868         }
2869 }
2870
2871 FLAC__OggDecoderAspectReadStatus read_callback_proxy_(const void *void_decoder, FLAC__byte buffer[], size_t *bytes, void *client_data)
2872 {
2873         FLAC__StreamDecoder *decoder = (FLAC__StreamDecoder*)void_decoder;
2874
2875         switch(decoder->private_->read_callback(decoder, buffer, bytes, client_data)) {
2876                 case FLAC__STREAM_DECODER_READ_STATUS_CONTINUE:
2877                         return FLAC__OGG_DECODER_ASPECT_READ_STATUS_OK;
2878                 case FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM:
2879                         return FLAC__OGG_DECODER_ASPECT_READ_STATUS_END_OF_STREAM;
2880                 case FLAC__STREAM_DECODER_READ_STATUS_ABORT:
2881                         return FLAC__OGG_DECODER_ASPECT_READ_STATUS_ABORT;
2882                 default:
2883                         /* double protection: */
2884                         FLAC__ASSERT(0);
2885                         return FLAC__OGG_DECODER_ASPECT_READ_STATUS_ABORT;
2886         }
2887 }
2888 #endif
2889
2890 FLAC__StreamDecoderWriteStatus write_audio_frame_to_client_(FLAC__StreamDecoder *decoder, const FLAC__Frame *frame, const FLAC__int32 * const buffer[])
2891 {
2892         if(decoder->private_->is_seeking) {
2893                 FLAC__uint64 this_frame_sample = frame->header.number.sample_number;
2894                 FLAC__uint64 next_frame_sample = this_frame_sample + (FLAC__uint64)frame->header.blocksize;
2895                 FLAC__uint64 target_sample = decoder->private_->target_sample;
2896
2897                 FLAC__ASSERT(frame->header.number_type == FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER);
2898
2899 #if FLAC__HAS_OGG
2900                 decoder->private_->got_a_frame = true;
2901 #endif
2902                 decoder->private_->last_frame = *frame; /* save the frame */
2903                 if(this_frame_sample <= target_sample && target_sample < next_frame_sample) { /* we hit our target frame */
2904                         unsigned delta = (unsigned)(target_sample - this_frame_sample);
2905                         /* kick out of seek mode */
2906                         decoder->private_->is_seeking = false;
2907                         /* shift out the samples before target_sample */
2908                         if(delta > 0) {
2909                                 unsigned channel;
2910                                 const FLAC__int32 *newbuffer[FLAC__MAX_CHANNELS];
2911                                 for(channel = 0; channel < frame->header.channels; channel++)
2912                                         newbuffer[channel] = buffer[channel] + delta;
2913                                 decoder->private_->last_frame.header.blocksize -= delta;
2914                                 decoder->private_->last_frame.header.number.sample_number += (FLAC__uint64)delta;
2915                                 /* write the relevant samples */
2916                                 return decoder->private_->write_callback(decoder, &decoder->private_->last_frame, newbuffer, decoder->private_->client_data);
2917                         }
2918                         else {
2919                                 /* write the relevant samples */
2920                                 return decoder->private_->write_callback(decoder, frame, buffer, decoder->private_->client_data);
2921                         }
2922                 }
2923                 else {
2924                         return FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE;
2925                 }
2926         }
2927         else {
2928                 /*
2929                  * If we never got STREAMINFO, turn off MD5 checking to save
2930                  * cycles since we don't have a sum to compare to anyway
2931                  */
2932                 if(!decoder->private_->has_stream_info)
2933                         decoder->private_->do_md5_checking = false;
2934                 if(decoder->private_->do_md5_checking) {
2935                         if(!FLAC__MD5Accumulate(&decoder->private_->md5context, buffer, frame->header.channels, frame->header.blocksize, (frame->header.bits_per_sample+7) / 8))
2936                                 return FLAC__STREAM_DECODER_WRITE_STATUS_ABORT;
2937                 }
2938                 return decoder->private_->write_callback(decoder, frame, buffer, decoder->private_->client_data);
2939         }
2940 }
2941
2942 void send_error_to_client_(const FLAC__StreamDecoder *decoder, FLAC__StreamDecoderErrorStatus status)
2943 {
2944         if(!decoder->private_->is_seeking)
2945                 decoder->private_->error_callback(decoder, status, decoder->private_->client_data);
2946         else if(status == FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM)
2947                 decoder->private_->unparseable_frame_count++;
2948 }
2949
2950 FLAC__bool seek_to_absolute_sample_(FLAC__StreamDecoder *decoder, FLAC__uint64 stream_length, FLAC__uint64 target_sample)
2951 {
2952         FLAC__uint64 first_frame_offset = decoder->private_->first_frame_offset, lower_bound, upper_bound, lower_bound_sample, upper_bound_sample, this_frame_sample;
2953         FLAC__int64 pos = -1;
2954         int i;
2955         unsigned approx_bytes_per_frame;
2956         FLAC__bool first_seek = true;
2957         const FLAC__uint64 total_samples = FLAC__stream_decoder_get_total_samples(decoder);
2958         const unsigned min_blocksize = decoder->private_->stream_info.data.stream_info.min_blocksize;
2959         const unsigned max_blocksize = decoder->private_->stream_info.data.stream_info.max_blocksize;
2960         const unsigned max_framesize = decoder->private_->stream_info.data.stream_info.max_framesize;
2961         const unsigned min_framesize = decoder->private_->stream_info.data.stream_info.min_framesize;
2962         /* take these from the current frame in case they've changed mid-stream */
2963         unsigned channels = FLAC__stream_decoder_get_channels(decoder);
2964         unsigned bps = FLAC__stream_decoder_get_bits_per_sample(decoder);
2965         const FLAC__StreamMetadata_SeekTable *seek_table = decoder->private_->has_seek_table? &decoder->private_->seek_table.data.seek_table : 0;
2966
2967         /* use values from stream info if we didn't decode a frame */
2968         if(channels == 0)
2969                 channels = decoder->private_->stream_info.data.stream_info.channels;
2970         if(bps == 0)
2971                 bps = decoder->private_->stream_info.data.stream_info.bits_per_sample;
2972
2973         /* we are just guessing here */
2974         if(max_framesize > 0)
2975                 approx_bytes_per_frame = (max_framesize + min_framesize) / 2 + 1;
2976         /*
2977          * Check if it's a known fixed-blocksize stream.  Note that though
2978          * the spec doesn't allow zeroes in the STREAMINFO block, we may
2979          * never get a STREAMINFO block when decoding so the value of
2980          * min_blocksize might be zero.
2981          */
2982         else if(min_blocksize == max_blocksize && min_blocksize > 0) {
2983                 /* note there are no () around 'bps/8' to keep precision up since it's an integer calulation */
2984                 approx_bytes_per_frame = min_blocksize * channels * bps/8 + 64;
2985         }
2986         else
2987                 approx_bytes_per_frame = 4096 * channels * bps/8 + 64;
2988
2989         /*
2990          * First, we set an upper and lower bound on where in the
2991          * stream we will search.  For now we assume the worst case
2992          * scenario, which is our best guess at the beginning of
2993          * the first frame and end of the stream.
2994          */
2995         lower_bound = first_frame_offset;
2996         lower_bound_sample = 0;
2997         upper_bound = stream_length;
2998         upper_bound_sample = total_samples > 0 ? total_samples : target_sample /*estimate it*/;
2999
3000         /*
3001          * Now we refine the bounds if we have a seektable with
3002          * suitable points.  Note that according to the spec they
3003          * must be ordered by ascending sample number.
3004          *
3005          * Note: to protect against invalid seek tables we will ignore points
3006          * that have frame_samples==0 or sample_number>=total_samples
3007          */
3008         if(seek_table) {
3009                 FLAC__uint64 new_lower_bound = lower_bound;
3010                 FLAC__uint64 new_upper_bound = upper_bound;
3011                 FLAC__uint64 new_lower_bound_sample = lower_bound_sample;
3012                 FLAC__uint64 new_upper_bound_sample = upper_bound_sample;
3013
3014                 /* find the closest seek point <= target_sample, if it exists */
3015                 for(i = (int)seek_table->num_points - 1; i >= 0; i--) {
3016                         if(
3017                                 seek_table->points[i].sample_number != FLAC__STREAM_METADATA_SEEKPOINT_PLACEHOLDER &&
3018                                 seek_table->points[i].frame_samples > 0 && /* defense against bad seekpoints */
3019                                 (total_samples <= 0 || seek_table->points[i].sample_number < total_samples) && /* defense against bad seekpoints */
3020                                 seek_table->points[i].sample_number <= target_sample
3021                         )
3022                                 break;
3023                 }
3024                 if(i >= 0) { /* i.e. we found a suitable seek point... */
3025                         new_lower_bound = first_frame_offset + seek_table->points[i].stream_offset;
3026                         new_lower_bound_sample = seek_table->points[i].sample_number;
3027                 }
3028
3029                 /* find the closest seek point > target_sample, if it exists */
3030                 for(i = 0; i < (int)seek_table->num_points; i++) {
3031                         if(
3032                                 seek_table->points[i].sample_number != FLAC__STREAM_METADATA_SEEKPOINT_PLACEHOLDER &&
3033                                 seek_table->points[i].frame_samples > 0 && /* defense against bad seekpoints */
3034                                 (total_samples <= 0 || seek_table->points[i].sample_number < total_samples) && /* defense against bad seekpoints */
3035                                 seek_table->points[i].sample_number > target_sample
3036                         )
3037                                 break;
3038                 }
3039                 if(i < (int)seek_table->num_points) { /* i.e. we found a suitable seek point... */
3040                         new_upper_bound = first_frame_offset + seek_table->points[i].stream_offset;
3041                         new_upper_bound_sample = seek_table->points[i].sample_number;
3042                 }
3043                 /* final protection against unsorted seek tables; keep original values if bogus */
3044                 if(new_upper_bound >= new_lower_bound) {
3045                         lower_bound = new_lower_bound;
3046                         upper_bound = new_upper_bound;
3047                         lower_bound_sample = new_lower_bound_sample;
3048                         upper_bound_sample = new_upper_bound_sample;
3049                 }
3050         }
3051
3052         FLAC__ASSERT(upper_bound_sample >= lower_bound_sample);
3053         /* there are 2 insidious ways that the following equality occurs, which
3054          * we need to fix:
3055          *  1) total_samples is 0 (unknown) and target_sample is 0
3056          *  2) total_samples is 0 (unknown) and target_sample happens to be
3057          *     exactly equal to the last seek point in the seek table; this
3058          *     means there is no seek point above it, and upper_bound_samples
3059          *     remains equal to the estimate (of target_samples) we made above
3060          * in either case it does not hurt to move upper_bound_sample up by 1
3061          */
3062         if(upper_bound_sample == lower_bound_sample)
3063                 upper_bound_sample++;
3064
3065         decoder->private_->target_sample = target_sample;
3066         while(1) {
3067                 /* check if the bounds are still ok */
3068                 if (lower_bound_sample >= upper_bound_sample || lower_bound > upper_bound) {
3069                         decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3070                         return false;
3071                 }
3072 #ifndef FLAC__INTEGER_ONLY_LIBRARY
3073 #if defined _MSC_VER || defined __MINGW32__
3074                 /* with VC++ you have to spoon feed it the casting */
3075                 pos = (FLAC__int64)lower_bound + (FLAC__int64)((FLAC__double)(FLAC__int64)(target_sample - lower_bound_sample) / (FLAC__double)(FLAC__int64)(upper_bound_sample - lower_bound_sample) * (FLAC__double)(FLAC__int64)(upper_bound - lower_bound)) - approx_bytes_per_frame;
3076 #else
3077                 pos = (FLAC__int64)lower_bound + (FLAC__int64)((FLAC__double)(target_sample - lower_bound_sample) / (FLAC__double)(upper_bound_sample - lower_bound_sample) * (FLAC__double)(upper_bound - lower_bound)) - approx_bytes_per_frame;
3078 #endif
3079 #else
3080                 /* a little less accurate: */
3081                 if(upper_bound - lower_bound < 0xffffffff)
3082                         pos = (FLAC__int64)lower_bound + (FLAC__int64)(((target_sample - lower_bound_sample) * (upper_bound - lower_bound)) / (upper_bound_sample - lower_bound_sample)) - approx_bytes_per_frame;
3083                 else /* @@@ WATCHOUT, ~2TB limit */
3084                         pos = (FLAC__int64)lower_bound + (FLAC__int64)((((target_sample - lower_bound_sample)>>8) * ((upper_bound - lower_bound)>>8)) / ((upper_bound_sample - lower_bound_sample)>>16)) - approx_bytes_per_frame;
3085 #endif
3086                 if(pos >= (FLAC__int64)upper_bound)
3087                         pos = (FLAC__int64)upper_bound - 1;
3088                 if(pos < (FLAC__int64)lower_bound)
3089                         pos = (FLAC__int64)lower_bound;
3090                 if(decoder->private_->seek_callback(decoder, (FLAC__uint64)pos, decoder->private_->client_data) != FLAC__STREAM_DECODER_SEEK_STATUS_OK) {
3091                         decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3092                         return false;
3093                 }
3094                 if(!FLAC__stream_decoder_flush(decoder)) {
3095                         /* above call sets the state for us */
3096                         return false;
3097                 }
3098                 /* Now we need to get a frame.  First we need to reset our
3099                  * unparseable_frame_count; if we get too many unparseable
3100                  * frames in a row, the read callback will return
3101                  * FLAC__STREAM_DECODER_READ_STATUS_ABORT, causing
3102                  * FLAC__stream_decoder_process_single() to return false.
3103                  */
3104                 decoder->private_->unparseable_frame_count = 0;
3105                 if(!FLAC__stream_decoder_process_single(decoder)) {
3106                         decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3107                         return false;
3108                 }
3109                 /* our write callback will change the state when it gets to the target frame */
3110                 /* actually, we could have got_a_frame if our decoder is at FLAC__STREAM_DECODER_END_OF_STREAM so we need to check for that also */
3111 #if 0
3112                 /*@@@@@@ used to be the following; not clear if the check for end of stream is needed anymore */
3113                 if(decoder->protected_->state != FLAC__SEEKABLE_STREAM_DECODER_SEEKING && decoder->protected_->state != FLAC__STREAM_DECODER_END_OF_STREAM)
3114                         break;
3115 #endif
3116                 if(!decoder->private_->is_seeking)
3117                         break;
3118
3119                 FLAC__ASSERT(decoder->private_->last_frame.header.number_type == FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER);
3120                 this_frame_sample = decoder->private_->last_frame.header.number.sample_number;
3121
3122                 if (0 == decoder->private_->samples_decoded || (this_frame_sample + decoder->private_->last_frame.header.blocksize >= upper_bound_sample && !first_seek)) {
3123                         if (pos == (FLAC__int64)lower_bound) {
3124                                 /* can't move back any more than the first frame, something is fatally wrong */
3125                                 decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3126                                 return false;
3127                         }
3128                         /* our last move backwards wasn't big enough, try again */
3129                         approx_bytes_per_frame = approx_bytes_per_frame? approx_bytes_per_frame * 2 : 16;
3130                         continue;
3131                 }
3132                 /* allow one seek over upper bound, so we can get a correct upper_bound_sample for streams with unknown total_samples */
3133                 first_seek = false;
3134
3135                 /* make sure we are not seeking in corrupted stream */
3136                 if (this_frame_sample < lower_bound_sample) {
3137                         decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3138                         return false;
3139                 }
3140
3141                 /* we need to narrow the search */
3142                 if(target_sample < this_frame_sample) {
3143                         upper_bound_sample = this_frame_sample + decoder->private_->last_frame.header.blocksize;
3144 /*@@@@@@ what will decode position be if at end of stream? */
3145                         if(!FLAC__stream_decoder_get_decode_position(decoder, &upper_bound)) {
3146                                 decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3147                                 return false;
3148                         }
3149                         approx_bytes_per_frame = (unsigned)(2 * (upper_bound - pos) / 3 + 16);
3150                 }
3151                 else { /* target_sample >= this_frame_sample + this frame's blocksize */
3152                         lower_bound_sample = this_frame_sample + decoder->private_->last_frame.header.blocksize;
3153                         if(!FLAC__stream_decoder_get_decode_position(decoder, &lower_bound)) {
3154                                 decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3155                                 return false;
3156                         }
3157                         approx_bytes_per_frame = (unsigned)(2 * (lower_bound - pos) / 3 + 16);
3158                 }
3159         }
3160
3161         return true;
3162 }
3163
3164 #if FLAC__HAS_OGG
3165 FLAC__bool seek_to_absolute_sample_ogg_(FLAC__StreamDecoder *decoder, FLAC__uint64 stream_length, FLAC__uint64 target_sample)
3166 {
3167         FLAC__uint64 left_pos = 0, right_pos = stream_length;
3168         FLAC__uint64 left_sample = 0, right_sample = FLAC__stream_decoder_get_total_samples(decoder);
3169         FLAC__uint64 this_frame_sample = (FLAC__uint64)0 - 1;
3170         FLAC__uint64 pos = 0; /* only initialized to avoid compiler warning */
3171         FLAC__bool did_a_seek;
3172         unsigned iteration = 0;
3173
3174         /* In the first iterations, we will calculate the target byte position
3175          * by the distance from the target sample to left_sample and
3176          * right_sample (let's call it "proportional search").  After that, we
3177          * will switch to binary search.
3178          */
3179         unsigned BINARY_SEARCH_AFTER_ITERATION = 2;
3180
3181         /* We will switch to a linear search once our current sample is less
3182          * than this number of samples ahead of the target sample
3183          */
3184         static const FLAC__uint64 LINEAR_SEARCH_WITHIN_SAMPLES = FLAC__MAX_BLOCK_SIZE * 2;
3185
3186         /* If the total number of samples is unknown, use a large value, and
3187          * force binary search immediately.
3188          */
3189         if(right_sample == 0) {
3190                 right_sample = (FLAC__uint64)(-1);
3191                 BINARY_SEARCH_AFTER_ITERATION = 0;
3192         }
3193
3194         decoder->private_->target_sample = target_sample;
3195         for( ; ; iteration++) {
3196                 if (iteration == 0 || this_frame_sample > target_sample || target_sample - this_frame_sample > LINEAR_SEARCH_WITHIN_SAMPLES) {
3197                         if (iteration >= BINARY_SEARCH_AFTER_ITERATION) {
3198                                 pos = (right_pos + left_pos) / 2;
3199                         }
3200                         else {
3201 #ifndef FLAC__INTEGER_ONLY_LIBRARY
3202 #if defined _MSC_VER || defined __MINGW32__
3203                                 /* with MSVC you have to spoon feed it the casting */
3204                                 pos = (FLAC__uint64)((FLAC__double)(FLAC__int64)(target_sample - left_sample) / (FLAC__double)(FLAC__int64)(right_sample - left_sample) * (FLAC__double)(FLAC__int64)(right_pos - left_pos));
3205 #else
3206                                 pos = (FLAC__uint64)((FLAC__double)(target_sample - left_sample) / (FLAC__double)(right_sample - left_sample) * (FLAC__double)(right_pos - left_pos));
3207 #endif
3208 #else
3209                                 /* a little less accurate: */
3210                                 if ((target_sample-left_sample <= 0xffffffff) && (right_pos-left_pos <= 0xffffffff))
3211                                         pos = (FLAC__int64)(((target_sample-left_sample) * (right_pos-left_pos)) / (right_sample-left_sample));
3212                                 else /* @@@ WATCHOUT, ~2TB limit */
3213                                         pos = (FLAC__int64)((((target_sample-left_sample)>>8) * ((right_pos-left_pos)>>8)) / ((right_sample-left_sample)>>16));
3214 #endif
3215                                 /* @@@ TODO: might want to limit pos to some distance
3216                                  * before EOF, to make sure we land before the last frame,
3217                                  * thereby getting a this_frame_sample and so having a better
3218                                  * estimate.
3219                                  */
3220                         }
3221
3222                         /* physical seek */
3223                         if(decoder->private_->seek_callback((FLAC__StreamDecoder*)decoder, (FLAC__uint64)pos, decoder->private_->client_data) != FLAC__STREAM_DECODER_SEEK_STATUS_OK) {
3224                                 decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3225                                 return false;
3226                         }
3227                         if(!FLAC__stream_decoder_flush(decoder)) {
3228                                 /* above call sets the state for us */
3229                                 return false;
3230                         }
3231                         did_a_seek = true;
3232                 }
3233                 else
3234                         did_a_seek = false;
3235
3236                 decoder->private_->got_a_frame = false;
3237                 if(!FLAC__stream_decoder_process_single(decoder)) {
3238                         decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3239                         return false;
3240                 }
3241                 if(!decoder->private_->got_a_frame) {
3242                         if(did_a_seek) {
3243                                 /* this can happen if we seek to a point after the last frame; we drop
3244                                  * to binary search right away in this case to avoid any wasted
3245                                  * iterations of proportional search.
3246                                  */
3247                                 right_pos = pos;
3248                                 BINARY_SEARCH_AFTER_ITERATION = 0;
3249                         }
3250                         else {
3251                                 /* this can probably only happen if total_samples is unknown and the
3252                                  * target_sample is past the end of the stream
3253                                  */
3254                                 decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3255                                 return false;
3256                         }
3257                 }
3258                 /* our write callback will change the state when it gets to the target frame */
3259                 else if(!decoder->private_->is_seeking) {
3260                         break;
3261                 }
3262                 else {
3263                         this_frame_sample = decoder->private_->last_frame.header.number.sample_number;
3264                         FLAC__ASSERT(decoder->private_->last_frame.header.number_type == FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER);
3265
3266                         if (did_a_seek) {
3267                                 if (this_frame_sample <= target_sample) {
3268                                         /* The 'equal' case should not happen, since
3269                                          * FLAC__stream_decoder_process_single()
3270                                          * should recognize that it has hit the
3271                                          * target sample and we would exit through
3272                                          * the 'break' above.
3273                                          */
3274                                         FLAC__ASSERT(this_frame_sample != target_sample);
3275
3276                                         left_sample = this_frame_sample;
3277                                         /* sanity check to avoid infinite loop */
3278                                         if (left_pos == pos) {
3279                                                 decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3280                                                 return false;
3281                                         }
3282                                         left_pos = pos;
3283                                 }
3284                                 else if(this_frame_sample > target_sample) {
3285                                         right_sample = this_frame_sample;
3286                                         /* sanity check to avoid infinite loop */
3287                                         if (right_pos == pos) {
3288                                                 decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3289                                                 return false;
3290                                         }
3291                                         right_pos = pos;
3292                                 }
3293                         }
3294                 }
3295         }
3296
3297         return true;
3298 }
3299 #endif
3300
3301 FLAC__StreamDecoderReadStatus file_read_callback_(const FLAC__StreamDecoder *decoder, FLAC__byte buffer[], size_t *bytes, void *client_data)
3302 {
3303         (void)client_data;
3304
3305         if(*bytes > 0) {
3306                 *bytes = fread(buffer, sizeof(FLAC__byte), *bytes, decoder->private_->file);
3307                 if(ferror(decoder->private_->file))
3308                         return FLAC__STREAM_DECODER_READ_STATUS_ABORT;
3309                 else if(*bytes == 0)
3310                         return FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM;
3311                 else
3312                         return FLAC__STREAM_DECODER_READ_STATUS_CONTINUE;
3313         }
3314         else
3315                 return FLAC__STREAM_DECODER_READ_STATUS_ABORT; /* abort to avoid a deadlock */
3316 }
3317
3318 FLAC__StreamDecoderSeekStatus file_seek_callback_(const FLAC__StreamDecoder *decoder, FLAC__uint64 absolute_byte_offset, void *client_data)
3319 {
3320         (void)client_data;
3321
3322         if(decoder->private_->file == stdin)
3323                 return FLAC__STREAM_DECODER_SEEK_STATUS_UNSUPPORTED;
3324         else if(fseeko(decoder->private_->file, (FLAC__off_t)absolute_byte_offset, SEEK_SET) < 0)
3325                 return FLAC__STREAM_DECODER_SEEK_STATUS_ERROR;
3326         else
3327                 return FLAC__STREAM_DECODER_SEEK_STATUS_OK;
3328 }
3329
3330 FLAC__StreamDecoderTellStatus file_tell_callback_(const FLAC__StreamDecoder *decoder, FLAC__uint64 *absolute_byte_offset, void *client_data)
3331 {
3332         FLAC__off_t pos;
3333         (void)client_data;
3334
3335         if(decoder->private_->file == stdin)
3336                 return FLAC__STREAM_DECODER_TELL_STATUS_UNSUPPORTED;
3337         else if((pos = ftello(decoder->private_->file)) < 0)
3338                 return FLAC__STREAM_DECODER_TELL_STATUS_ERROR;
3339         else {
3340                 *absolute_byte_offset = (FLAC__uint64)pos;
3341                 return FLAC__STREAM_DECODER_TELL_STATUS_OK;
3342         }
3343 }
3344
3345 FLAC__StreamDecoderLengthStatus file_length_callback_(const FLAC__StreamDecoder *decoder, FLAC__uint64 *stream_length, void *client_data)
3346 {
3347         struct flac_stat_s filestats;
3348         (void)client_data;
3349
3350         if(decoder->private_->file == stdin)
3351                 return FLAC__STREAM_DECODER_LENGTH_STATUS_UNSUPPORTED;
3352         else if(flac_fstat(fileno(decoder->private_->file), &filestats) != 0)
3353                 return FLAC__STREAM_DECODER_LENGTH_STATUS_ERROR;
3354         else {
3355                 *stream_length = (FLAC__uint64)filestats.st_size;
3356                 return FLAC__STREAM_DECODER_LENGTH_STATUS_OK;
3357         }
3358 }
3359
3360 FLAC__bool file_eof_callback_(const FLAC__StreamDecoder *decoder, void *client_data)
3361 {
3362         (void)client_data;
3363
3364         return feof(decoder->private_->file)? true : false;
3365 }