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 #if defined _MSC_VER || defined __MINGW32__
  37 #include <io.h> /* for _setmode() */
  38 #include <fcntl.h> /* for _O_BINARY */
  39 #endif
  40 #if defined __CYGWIN__ || defined __EMX__
  41 #include <io.h> /* for setmode(), O_BINARY */
  42 #include <fcntl.h> /* for _O_BINARY */
  43 #endif
  44 #include <stdio.h>
  45 #include <stdlib.h> /* for malloc() */
  46 #include <string.h> /* for memset/memcpy() */
  47 #include <sys/stat.h> /* for stat() */
  48 #include <sys/types.h> /* for off_t */
  49 #include "share/compat.h"
  50 #include "FLAC/assert.h"
  51 #include "share/alloc.h"
  52 #include "protected/stream_decoder.h"
  53 #include "private/bitreader.h"
  54 #include "private/bitmath.h"
  55 #include "private/cpu.h"
  56 #include "private/crc.h"
  57 #include "private/fixed.h"
  58 #include "private/format.h"
  59 #include "private/lpc.h"
  60 #include "private/md5.h"
  61 #include "private/memory.h"
  62 #include "private/macros.h"
  63
  64 /* adjust for compilers that can't understand using LLU suffix for uint64_t literals */
  65 #ifdef _MSC_VER
  66 #define FLAC__U64L(x) x
  67 #else
  68 #define FLAC__U64L(x) x##LLU
  69 #endif
  70
  71
  72 /* technically this should be in an "export.c" but this is convenient enough */
  73 FLAC_API int FLAC_API_SUPPORTS_OGG_FLAC =
  74 #if FLAC__HAS_OGG
  75         1
  76 #else
  77         0
  78 #endif
  79 ;
  80
  81
  82 /***********************************************************************
  83  *
  84  * Private static data
  85  *
  86  ***********************************************************************/
  87
  88 static FLAC__byte ID3V2_TAG_[3] = { 'I', 'D', '3' };
  89
  90 /***********************************************************************
  91  *
  92  * Private class method prototypes
  93  *
  94  ***********************************************************************/
  95
  96 static void set_defaults_(FLAC__StreamDecoder *decoder);
  97 static FILE *get_binary_stdin_(void);
  98 static FLAC__bool allocate_output_(FLAC__StreamDecoder *decoder, unsigned size, unsigned channels);
  99 static FLAC__bool has_id_filtered_(FLAC__StreamDecoder *decoder, FLAC__byte *id);
 100 static FLAC__bool find_metadata_(FLAC__StreamDecoder *decoder);
 101 static FLAC__bool read_metadata_(FLAC__StreamDecoder *decoder);
 102 static FLAC__bool read_metadata_streaminfo_(FLAC__StreamDecoder *decoder, FLAC__bool is_last, unsigned length);
 103 static FLAC__bool read_metadata_seektable_(FLAC__StreamDecoder *decoder, FLAC__bool is_last, unsigned length);
 104 static FLAC__bool read_metadata_vorbiscomment_(FLAC__StreamDecoder *decoder, FLAC__StreamMetadata_VorbisComment *obj);
 105 static FLAC__bool read_metadata_cuesheet_(FLAC__StreamDecoder *decoder, FLAC__StreamMetadata_CueSheet *obj);
 106 static FLAC__bool read_metadata_picture_(FLAC__StreamDecoder *decoder, FLAC__StreamMetadata_Picture *obj);
 107 static FLAC__bool skip_id3v2_tag_(FLAC__StreamDecoder *decoder);
 108 static FLAC__bool frame_sync_(FLAC__StreamDecoder *decoder);
 109 static FLAC__bool read_frame_(FLAC__StreamDecoder *decoder, FLAC__bool *got_a_frame, FLAC__bool do_full_decode);
 110 static FLAC__bool read_frame_header_(FLAC__StreamDecoder *decoder);
 111 static FLAC__bool read_subframe_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, FLAC__bool do_full_decode);
 112 static FLAC__bool read_subframe_constant_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, FLAC__bool do_full_decode);
 113 static FLAC__bool read_subframe_fixed_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, const unsigned order, FLAC__bool do_full_decode);
 114 static FLAC__bool read_subframe_lpc_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, const unsigned order, FLAC__bool do_full_decode);
 115 static FLAC__bool read_subframe_verbatim_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, FLAC__bool do_full_decode);
 116 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);
 117 static FLAC__bool read_zero_padding_(FLAC__StreamDecoder *decoder);
 118 static FLAC__bool read_callback_(FLAC__byte buffer[], size_t *bytes, void *client_data);
 119 #if FLAC__HAS_OGG
 120 static FLAC__StreamDecoderReadStatus read_callback_ogg_aspect_(const FLAC__StreamDecoder *decoder, FLAC__byte buffer[], size_t *bytes);
 121 static FLAC__OggDecoderAspectReadStatus read_callback_proxy_(const void *void_decoder, FLAC__byte buffer[], size_t *bytes, void *client_data);
 122 #endif
 123 static FLAC__StreamDecoderWriteStatus write_audio_frame_to_client_(FLAC__StreamDecoder *decoder, const FLAC__Frame *frame, const FLAC__int32 * const buffer[]);
 124 static void send_error_to_client_(const FLAC__StreamDecoder *decoder, FLAC__StreamDecoderErrorStatus status);
 125 static FLAC__bool seek_to_absolute_sample_(FLAC__StreamDecoder *decoder, FLAC__uint64 stream_length, FLAC__uint64 target_sample);
 126 #if FLAC__HAS_OGG
 127 static FLAC__bool seek_to_absolute_sample_ogg_(FLAC__StreamDecoder *decoder, FLAC__uint64 stream_length, FLAC__uint64 target_sample);
 128 #endif
 129 static FLAC__StreamDecoderReadStatus file_read_callback_(const FLAC__StreamDecoder *decoder, FLAC__byte buffer[], size_t *bytes, void *client_data);
 130 static FLAC__StreamDecoderSeekStatus file_seek_callback_(const FLAC__StreamDecoder *decoder, FLAC__uint64 absolute_byte_offset, void *client_data);
 131 static FLAC__StreamDecoderTellStatus file_tell_callback_(const FLAC__StreamDecoder *decoder, FLAC__uint64 *absolute_byte_offset, void *client_data);
 132 static FLAC__StreamDecoderLengthStatus file_length_callback_(const FLAC__StreamDecoder *decoder, FLAC__uint64 *stream_length, void *client_data);
 133 static FLAC__bool file_eof_callback_(const FLAC__StreamDecoder *decoder, void *client_data);
 134
 135 /***********************************************************************
 136  *
 137  * Private class data
 138  *
 139  ***********************************************************************/
 140
 141 typedef struct FLAC__StreamDecoderPrivate {
 142 #if FLAC__HAS_OGG
 143         FLAC__bool is_ogg;
 144 #endif
 145         FLAC__StreamDecoderReadCallback read_callback;
 146         FLAC__StreamDecoderSeekCallback seek_callback;
 147         FLAC__StreamDecoderTellCallback tell_callback;
 148         FLAC__StreamDecoderLengthCallback length_callback;
 149         FLAC__StreamDecoderEofCallback eof_callback;
 150         FLAC__StreamDecoderWriteCallback write_callback;
 151         FLAC__StreamDecoderMetadataCallback metadata_callback;
 152         FLAC__StreamDecoderErrorCallback error_callback;
 153         /* generic 32-bit datapath: */
 154         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[]);
 155         /* generic 64-bit datapath: */
 156         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[]);
 157         /* for use when the signal is <= 16 bits-per-sample, or <= 15 bits-per-sample on a side channel (which requires 1 extra bit): */
 158         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[]);
 159         /* 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: */
 160         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[]);
 161         FLAC__bool (*local_bitreader_read_rice_signed_block)(FLAC__BitReader *br, int vals[], unsigned nvals, unsigned parameter);
 162         void *client_data;
 163         FILE *file; /* only used if FLAC__stream_decoder_init_file()/FLAC__stream_decoder_init_file() called, else NULL */
 164         FLAC__BitReader *input;
 165         FLAC__int32 *output[FLAC__MAX_CHANNELS];
 166         FLAC__int32 *residual[FLAC__MAX_CHANNELS]; /* WATCHOUT: these are the aligned pointers; the real pointers that should be free()'d are residual_unaligned[] below */
 167         FLAC__EntropyCodingMethod_PartitionedRiceContents partitioned_rice_contents[FLAC__MAX_CHANNELS];
 168         unsigned output_capacity, output_channels;
 169         FLAC__uint32 fixed_block_size, next_fixed_block_size;
 170         FLAC__uint64 samples_decoded;
 171         FLAC__bool has_stream_info, has_seek_table;
 172         FLAC__StreamMetadata stream_info;
 173         FLAC__StreamMetadata seek_table;
 174         FLAC__bool metadata_filter[128]; /* MAGIC number 128 == total number of metadata block types == 1 << 7 */
 175         FLAC__byte *metadata_filter_ids;
 176         size_t metadata_filter_ids_count, metadata_filter_ids_capacity; /* units for both are IDs, not bytes */
 177         FLAC__Frame frame;
 178         FLAC__bool cached; /* true if there is a byte in lookahead */
 179         FLAC__CPUInfo cpuinfo;
 180         FLAC__byte header_warmup[2]; /* contains the sync code and reserved bits */
 181         FLAC__byte lookahead; /* temp storage when we need to look ahead one byte in the stream */
 182         /* unaligned (original) pointers to allocated data */
 183         FLAC__int32 *residual_unaligned[FLAC__MAX_CHANNELS];
 184         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 */
 185         FLAC__bool internal_reset_hack; /* used only during init() so we can call reset to set up the decoder without rewinding the input */
 186         FLAC__bool is_seeking;
 187         FLAC__MD5Context md5context;
 188         FLAC__byte computed_md5sum[16]; /* this is the sum we computed from the decoded data */
 189         /* (the rest of these are only used for seeking) */
 190         FLAC__Frame last_frame; /* holds the info of the last frame we seeked to */
 191         FLAC__uint64 first_frame_offset; /* hint to the seek routine of where in the stream the first audio frame starts */
 192         FLAC__uint64 target_sample;
 193         unsigned unparseable_frame_count; /* used to tell whether we're decoding a future version of FLAC or just got a bad sync */
 194 #if FLAC__HAS_OGG
 195         FLAC__bool got_a_frame; /* hack needed in Ogg FLAC seek routine to check when process_single() actually writes a frame */
 196 #endif
 197 } FLAC__StreamDecoderPrivate;
 198
 199 /***********************************************************************
 200  *
 201  * Public static class data
 202  *
 203  ***********************************************************************/
 204
 205 FLAC_API const char * const FLAC__StreamDecoderStateString[] = {
 206         "FLAC__STREAM_DECODER_SEARCH_FOR_METADATA",
 207         "FLAC__STREAM_DECODER_READ_METADATA",
 208         "FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC",
 209         "FLAC__STREAM_DECODER_READ_FRAME",
 210         "FLAC__STREAM_DECODER_END_OF_STREAM",
 211         "FLAC__STREAM_DECODER_OGG_ERROR",
 212         "FLAC__STREAM_DECODER_SEEK_ERROR",
 213         "FLAC__STREAM_DECODER_ABORTED",
 214         "FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR",
 215         "FLAC__STREAM_DECODER_UNINITIALIZED"
 216 };
 217
 218 FLAC_API const char * const FLAC__StreamDecoderInitStatusString[] = {
 219         "FLAC__STREAM_DECODER_INIT_STATUS_OK",
 220         "FLAC__STREAM_DECODER_INIT_STATUS_UNSUPPORTED_CONTAINER",
 221         "FLAC__STREAM_DECODER_INIT_STATUS_INVALID_CALLBACKS",
 222         "FLAC__STREAM_DECODER_INIT_STATUS_MEMORY_ALLOCATION_ERROR",
 223         "FLAC__STREAM_DECODER_INIT_STATUS_ERROR_OPENING_FILE",
 224         "FLAC__STREAM_DECODER_INIT_STATUS_ALREADY_INITIALIZED"
 225 };
 226
 227 FLAC_API const char * const FLAC__StreamDecoderReadStatusString[] = {
 228         "FLAC__STREAM_DECODER_READ_STATUS_CONTINUE",
 229         "FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM",
 230         "FLAC__STREAM_DECODER_READ_STATUS_ABORT"
 231 };
 232
 233 FLAC_API const char * const FLAC__StreamDecoderSeekStatusString[] = {
 234         "FLAC__STREAM_DECODER_SEEK_STATUS_OK",
 235         "FLAC__STREAM_DECODER_SEEK_STATUS_ERROR",
 236         "FLAC__STREAM_DECODER_SEEK_STATUS_UNSUPPORTED"
 237 };
 238
 239 FLAC_API const char * const FLAC__StreamDecoderTellStatusString[] = {
 240         "FLAC__STREAM_DECODER_TELL_STATUS_OK",
 241         "FLAC__STREAM_DECODER_TELL_STATUS_ERROR",
 242         "FLAC__STREAM_DECODER_TELL_STATUS_UNSUPPORTED"
 243 };
 244
 245 FLAC_API const char * const FLAC__StreamDecoderLengthStatusString[] = {
 246         "FLAC__STREAM_DECODER_LENGTH_STATUS_OK",
 247         "FLAC__STREAM_DECODER_LENGTH_STATUS_ERROR",
 248         "FLAC__STREAM_DECODER_LENGTH_STATUS_UNSUPPORTED"
 249 };
 250
 251 FLAC_API const char * const FLAC__StreamDecoderWriteStatusString[] = {
 252         "FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE",
 253         "FLAC__STREAM_DECODER_WRITE_STATUS_ABORT"
 254 };
 255
 256 FLAC_API const char * const FLAC__StreamDecoderErrorStatusString[] = {
 257         "FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC",
 258         "FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER",
 259         "FLAC__STREAM_DECODER_ERROR_STATUS_FRAME_CRC_MISMATCH",
 260         "FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM"
 261 };
 262
 263 /***********************************************************************
 264  *
 265  * Class constructor/destructor
 266  *
 267  ***********************************************************************/
 268 FLAC_API FLAC__StreamDecoder *FLAC__stream_decoder_new(void)
 269 {
 270         FLAC__StreamDecoder *decoder;
 271         unsigned i;
 272
 273         FLAC__ASSERT(sizeof(int) >= 4); /* we want to die right away if this is not true */
 274
 275         decoder = calloc(1, sizeof(FLAC__StreamDecoder));
 276         if(decoder == 0) {
 277                 return 0;
 278         }
 279
 280         decoder->protected_ = calloc(1, sizeof(FLAC__StreamDecoderProtected));
 281         if(decoder->protected_ == 0) {
 282                 free(decoder);
 283                 return 0;
 284         }
 285
 286         decoder->private_ = calloc(1, sizeof(FLAC__StreamDecoderPrivate));
 287         if(decoder->private_ == 0) {
 288                 free(decoder->protected_);
 289                 free(decoder);
 290                 return 0;
 291         }
 292
 293         decoder->private_->input = FLAC__bitreader_new();
 294         if(decoder->private_->input == 0) {
 295                 free(decoder->private_);
 296                 free(decoder->protected_);
 297                 free(decoder);
 298                 return 0;
 299         }
 300
 301         decoder->private_->metadata_filter_ids_capacity = 16;
 302         if(0 == (decoder->private_->metadata_filter_ids = malloc((FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8) * decoder->private_->metadata_filter_ids_capacity))) {
 303                 FLAC__bitreader_delete(decoder->private_->input);
 304                 free(decoder->private_);
 305                 free(decoder->protected_);
 306                 free(decoder);
 307                 return 0;
 308         }
 309
 310         for(i = 0; i < FLAC__MAX_CHANNELS; i++) {
 311                 decoder->private_->output[i] = 0;
 312                 decoder->private_->residual_unaligned[i] = decoder->private_->residual[i] = 0;
 313         }
 314
 315         decoder->private_->output_capacity = 0;
 316         decoder->private_->output_channels = 0;
 317         decoder->private_->has_seek_table = false;
 318
 319         for(i = 0; i < FLAC__MAX_CHANNELS; i++)
 320                 FLAC__format_entropy_coding_method_partitioned_rice_contents_init(&decoder->private_->partitioned_rice_contents[i]);
 321
 322         decoder->private_->file = 0;
 323
 324         set_defaults_(decoder);
 325
 326         decoder->protected_->state = FLAC__STREAM_DECODER_UNINITIALIZED;
 327
 328         return decoder;
 329 }
 330
 331 FLAC_API void FLAC__stream_decoder_delete(FLAC__StreamDecoder *decoder)
 332 {
 333         unsigned i;
 334
 335         if (decoder == NULL)
 336                 return ;
 337
 338         FLAC__ASSERT(0 != decoder->protected_);
 339         FLAC__ASSERT(0 != decoder->private_);
 340         FLAC__ASSERT(0 != decoder->private_->input);
 341
 342         (void)FLAC__stream_decoder_finish(decoder);
 343
 344         if(0 != decoder->private_->metadata_filter_ids)
 345                 free(decoder->private_->metadata_filter_ids);
 346
 347         FLAC__bitreader_delete(decoder->private_->input);
 348
 349         for(i = 0; i < FLAC__MAX_CHANNELS; i++)
 350                 FLAC__format_entropy_coding_method_partitioned_rice_contents_clear(&decoder->private_->partitioned_rice_contents[i]);
 351
 352         free(decoder->private_);
 353         free(decoder->protected_);
 354         free(decoder);
 355 }
 356
 357 /***********************************************************************
 358  *
 359  * Public class methods
 360  *
 361  ***********************************************************************/
 362
 363 static FLAC__StreamDecoderInitStatus init_stream_internal_(
 364         FLAC__StreamDecoder *decoder,
 365         FLAC__StreamDecoderReadCallback read_callback,
 366         FLAC__StreamDecoderSeekCallback seek_callback,
 367         FLAC__StreamDecoderTellCallback tell_callback,
 368         FLAC__StreamDecoderLengthCallback length_callback,
 369         FLAC__StreamDecoderEofCallback eof_callback,
 370         FLAC__StreamDecoderWriteCallback write_callback,
 371         FLAC__StreamDecoderMetadataCallback metadata_callback,
 372         FLAC__StreamDecoderErrorCallback error_callback,
 373         void *client_data,
 374         FLAC__bool is_ogg
 375 )
 376 {
 377         FLAC__ASSERT(0 != decoder);
 378
 379         if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
 380                 return FLAC__STREAM_DECODER_INIT_STATUS_ALREADY_INITIALIZED;
 381
 382 #if !FLAC__HAS_OGG
 383         if(is_ogg)
 384                 return FLAC__STREAM_DECODER_INIT_STATUS_UNSUPPORTED_CONTAINER;
 385 #endif
 386
 387         if(
 388                 0 == read_callback ||
 389                 0 == write_callback ||
 390                 0 == error_callback ||
 391                 (seek_callback && (0 == tell_callback || 0 == length_callback || 0 == eof_callback))
 392         )
 393                 return FLAC__STREAM_DECODER_INIT_STATUS_INVALID_CALLBACKS;
 394
 395 #if FLAC__HAS_OGG
 396         decoder->private_->is_ogg = is_ogg;
 397         if(is_ogg && !FLAC__ogg_decoder_aspect_init(&decoder->protected_->ogg_decoder_aspect))
 398                 return decoder->protected_->state = FLAC__STREAM_DECODER_OGG_ERROR;
 399 #endif
 400
 401         /*
 402          * get the CPU info and set the function pointers
 403          */
 404         FLAC__cpu_info(&decoder->private_->cpuinfo);
 405         /* first default to the non-asm routines */
 406         decoder->private_->local_lpc_restore_signal = FLAC__lpc_restore_signal;
 407         decoder->private_->local_lpc_restore_signal_64bit = FLAC__lpc_restore_signal_wide;
 408         decoder->private_->local_lpc_restore_signal_16bit = FLAC__lpc_restore_signal;
 409         decoder->private_->local_lpc_restore_signal_16bit_order8 = FLAC__lpc_restore_signal;
 410         decoder->private_->local_bitreader_read_rice_signed_block = FLAC__bitreader_read_rice_signed_block;
 411         /* now override with asm where appropriate */
 412 #ifndef FLAC__NO_ASM
 413         if(decoder->private_->cpuinfo.use_asm) {
 414 #ifdef FLAC__CPU_IA32
 415                 FLAC__ASSERT(decoder->private_->cpuinfo.type == FLAC__CPUINFO_TYPE_IA32);
 416 #ifdef FLAC__HAS_NASM
 417 #if 1 /*@@@@@@ OPT: not clearly faster, needs more testing */
 418                 if(decoder->private_->cpuinfo.data.ia32.bswap)
 419                         decoder->private_->local_bitreader_read_rice_signed_block = FLAC__bitreader_read_rice_signed_block_asm_ia32_bswap;
 420 #endif
 421                 if(decoder->private_->cpuinfo.data.ia32.mmx) {
 422                         decoder->private_->local_lpc_restore_signal = FLAC__lpc_restore_signal_asm_ia32;
 423                         decoder->private_->local_lpc_restore_signal_16bit = FLAC__lpc_restore_signal_asm_ia32_mmx;
 424                         decoder->private_->local_lpc_restore_signal_16bit_order8 = FLAC__lpc_restore_signal_asm_ia32_mmx;
 425                 }
 426                 else {
 427                         decoder->private_->local_lpc_restore_signal = FLAC__lpc_restore_signal_asm_ia32;
 428                         decoder->private_->local_lpc_restore_signal_16bit = FLAC__lpc_restore_signal_asm_ia32;
 429                         decoder->private_->local_lpc_restore_signal_16bit_order8 = FLAC__lpc_restore_signal_asm_ia32;
 430                 }
 431 #endif
 432 #elif defined FLAC__CPU_PPC
 433                 FLAC__ASSERT(decoder->private_->cpuinfo.type == FLAC__CPUINFO_TYPE_PPC);
 434                 if(decoder->private_->cpuinfo.data.ppc.altivec) {
 435                         decoder->private_->local_lpc_restore_signal_16bit = FLAC__lpc_restore_signal_asm_ppc_altivec_16;
 436                         decoder->private_->local_lpc_restore_signal_16bit_order8 = FLAC__lpc_restore_signal_asm_ppc_altivec_16_order8;
 437                 }
 438 #endif
 439         }
 440 #endif
 441
 442         /* from here on, errors are fatal */
 443
 444         if(!FLAC__bitreader_init(decoder->private_->input, decoder->private_->cpuinfo, read_callback_, decoder)) {
 445                 decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
 446                 return FLAC__STREAM_DECODER_INIT_STATUS_MEMORY_ALLOCATION_ERROR;
 447         }
 448
 449         decoder->private_->read_callback = read_callback;
 450         decoder->private_->seek_callback = seek_callback;
 451         decoder->private_->tell_callback = tell_callback;
 452         decoder->private_->length_callback = length_callback;
 453         decoder->private_->eof_callback = eof_callback;
 454         decoder->private_->write_callback = write_callback;
 455         decoder->private_->metadata_callback = metadata_callback;
 456         decoder->private_->error_callback = error_callback;
 457         decoder->private_->client_data = client_data;
 458         decoder->private_->fixed_block_size = decoder->private_->next_fixed_block_size = 0;
 459         decoder->private_->samples_decoded = 0;
 460         decoder->private_->has_stream_info = false;
 461         decoder->private_->cached = false;
 462
 463         decoder->private_->do_md5_checking = decoder->protected_->md5_checking;
 464         decoder->private_->is_seeking = false;
 465
 466         decoder->private_->internal_reset_hack = true; /* so the following reset does not try to rewind the input */
 467         if(!FLAC__stream_decoder_reset(decoder)) {
 468                 /* above call sets the state for us */
 469                 return FLAC__STREAM_DECODER_INIT_STATUS_MEMORY_ALLOCATION_ERROR;
 470         }
 471
 472         return FLAC__STREAM_DECODER_INIT_STATUS_OK;
 473 }
 474
 475 FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_stream(
 476         FLAC__StreamDecoder *decoder,
 477         FLAC__StreamDecoderReadCallback read_callback,
 478         FLAC__StreamDecoderSeekCallback seek_callback,
 479         FLAC__StreamDecoderTellCallback tell_callback,
 480         FLAC__StreamDecoderLengthCallback length_callback,
 481         FLAC__StreamDecoderEofCallback eof_callback,
 482         FLAC__StreamDecoderWriteCallback write_callback,
 483         FLAC__StreamDecoderMetadataCallback metadata_callback,
 484         FLAC__StreamDecoderErrorCallback error_callback,
 485         void *client_data
 486 )
 487 {
 488         return init_stream_internal_(
 489                 decoder,
 490                 read_callback,
 491                 seek_callback,
 492                 tell_callback,
 493                 length_callback,
 494                 eof_callback,
 495                 write_callback,
 496                 metadata_callback,
 497                 error_callback,
 498                 client_data,
 499                 /*is_ogg=*/false
 500         );
 501 }
 502
 503 FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_ogg_stream(
 504         FLAC__StreamDecoder *decoder,
 505         FLAC__StreamDecoderReadCallback read_callback,
 506         FLAC__StreamDecoderSeekCallback seek_callback,
 507         FLAC__StreamDecoderTellCallback tell_callback,
 508         FLAC__StreamDecoderLengthCallback length_callback,
 509         FLAC__StreamDecoderEofCallback eof_callback,
 510         FLAC__StreamDecoderWriteCallback write_callback,
 511         FLAC__StreamDecoderMetadataCallback metadata_callback,
 512         FLAC__StreamDecoderErrorCallback error_callback,
 513         void *client_data
 514 )
 515 {
 516         return init_stream_internal_(
 517                 decoder,
 518                 read_callback,
 519                 seek_callback,
 520                 tell_callback,
 521                 length_callback,
 522                 eof_callback,
 523                 write_callback,
 524                 metadata_callback,
 525                 error_callback,
 526                 client_data,
 527                 /*is_ogg=*/true
 528         );
 529 }
 530
 531 static FLAC__StreamDecoderInitStatus init_FILE_internal_(
 532         FLAC__StreamDecoder *decoder,
 533         FILE *file,
 534         FLAC__StreamDecoderWriteCallback write_callback,
 535         FLAC__StreamDecoderMetadataCallback metadata_callback,
 536         FLAC__StreamDecoderErrorCallback error_callback,
 537         void *client_data,
 538         FLAC__bool is_ogg
 539 )
 540 {
 541         FLAC__ASSERT(0 != decoder);
 542         FLAC__ASSERT(0 != file);
 543
 544         if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
 545                 return decoder->protected_->state = FLAC__STREAM_DECODER_INIT_STATUS_ALREADY_INITIALIZED;
 546
 547         if(0 == write_callback || 0 == error_callback)
 548                 return decoder->protected_->state = FLAC__STREAM_DECODER_INIT_STATUS_INVALID_CALLBACKS;
 549
 550         /*
 551          * To make sure that our file does not go unclosed after an error, we
 552          * must assign the FILE pointer before any further error can occur in
 553          * this routine.
 554          */
 555         if(file == stdin)
 556                 file = get_binary_stdin_(); /* just to be safe */
 557
 558         decoder->private_->file = file;
 559
 560         return init_stream_internal_(
 561                 decoder,
 562                 file_read_callback_,
 563                 decoder->private_->file == stdin? 0: file_seek_callback_,
 564                 decoder->private_->file == stdin? 0: file_tell_callback_,
 565                 decoder->private_->file == stdin? 0: file_length_callback_,
 566                 file_eof_callback_,
 567                 write_callback,
 568                 metadata_callback,
 569                 error_callback,
 570                 client_data,
 571                 is_ogg
 572         );
 573 }
 574
 575 FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_FILE(
 576         FLAC__StreamDecoder *decoder,
 577         FILE *file,
 578         FLAC__StreamDecoderWriteCallback write_callback,
 579         FLAC__StreamDecoderMetadataCallback metadata_callback,
 580         FLAC__StreamDecoderErrorCallback error_callback,
 581         void *client_data
 582 )
 583 {
 584         return init_FILE_internal_(decoder, file, write_callback, metadata_callback, error_callback, client_data, /*is_ogg=*/false);
 585 }
 586
 587 FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_ogg_FILE(
 588         FLAC__StreamDecoder *decoder,
 589         FILE *file,
 590         FLAC__StreamDecoderWriteCallback write_callback,
 591         FLAC__StreamDecoderMetadataCallback metadata_callback,
 592         FLAC__StreamDecoderErrorCallback error_callback,
 593         void *client_data
 594 )
 595 {
 596         return init_FILE_internal_(decoder, file, write_callback, metadata_callback, error_callback, client_data, /*is_ogg=*/true);
 597 }
 598
 599 static FLAC__StreamDecoderInitStatus init_file_internal_(
 600         FLAC__StreamDecoder *decoder,
 601         const char *filename,
 602         FLAC__StreamDecoderWriteCallback write_callback,
 603         FLAC__StreamDecoderMetadataCallback metadata_callback,
 604         FLAC__StreamDecoderErrorCallback error_callback,
 605         void *client_data,
 606         FLAC__bool is_ogg
 607 )
 608 {
 609         FILE *file;
 610
 611         FLAC__ASSERT(0 != decoder);
 612
 613         /*
 614          * To make sure that our file does not go unclosed after an error, we
 615          * have to do the same entrance checks here that are later performed
 616          * in FLAC__stream_decoder_init_FILE() before the FILE* is assigned.
 617          */
 618         if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
 619                 return decoder->protected_->state = FLAC__STREAM_DECODER_INIT_STATUS_ALREADY_INITIALIZED;
 620
 621         if(0 == write_callback || 0 == error_callback)
 622                 return decoder->protected_->state = FLAC__STREAM_DECODER_INIT_STATUS_INVALID_CALLBACKS;
 623
 624         file = filename? fopen(filename, "rb") : stdin;
 625
 626         if(0 == file)
 627                 return FLAC__STREAM_DECODER_INIT_STATUS_ERROR_OPENING_FILE;
 628
 629         return init_FILE_internal_(decoder, file, write_callback, metadata_callback, error_callback, client_data, is_ogg);
 630 }
 631
 632 FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_file(
 633         FLAC__StreamDecoder *decoder,
 634         const char *filename,
 635         FLAC__StreamDecoderWriteCallback write_callback,
 636         FLAC__StreamDecoderMetadataCallback metadata_callback,
 637         FLAC__StreamDecoderErrorCallback error_callback,
 638         void *client_data
 639 )
 640 {
 641         return init_file_internal_(decoder, filename, write_callback, metadata_callback, error_callback, client_data, /*is_ogg=*/false);
 642 }
 643
 644 FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_ogg_file(
 645         FLAC__StreamDecoder *decoder,
 646         const char *filename,
 647         FLAC__StreamDecoderWriteCallback write_callback,
 648         FLAC__StreamDecoderMetadataCallback metadata_callback,
 649         FLAC__StreamDecoderErrorCallback error_callback,
 650         void *client_data
 651 )
 652 {
 653         return init_file_internal_(decoder, filename, write_callback, metadata_callback, error_callback, client_data, /*is_ogg=*/true);
 654 }
 655
 656 FLAC_API FLAC__bool FLAC__stream_decoder_finish(FLAC__StreamDecoder *decoder)
 657 {
 658         FLAC__bool md5_failed = false;
 659         unsigned i;
 660
 661         FLAC__ASSERT(0 != decoder);
 662         FLAC__ASSERT(0 != decoder->private_);
 663         FLAC__ASSERT(0 != decoder->protected_);
 664
 665         if(decoder->protected_->state == FLAC__STREAM_DECODER_UNINITIALIZED)
 666                 return true;
 667
 668         /* see the comment in FLAC__seekable_stream_decoder_reset() as to why we
 669          * always call FLAC__MD5Final()
 670          */
 671         FLAC__MD5Final(decoder->private_->computed_md5sum, &decoder->private_->md5context);
 672
 673         if(decoder->private_->has_seek_table && 0 != decoder->private_->seek_table.data.seek_table.points) {
 674                 free(decoder->private_->seek_table.data.seek_table.points);
 675                 decoder->private_->seek_table.data.seek_table.points = 0;
 676                 decoder->private_->has_seek_table = false;
 677         }
 678         FLAC__bitreader_free(decoder->private_->input);
 679         for(i = 0; i < FLAC__MAX_CHANNELS; i++) {
 680                 /* WATCHOUT:
 681                  * FLAC__lpc_restore_signal_asm_ia32_mmx() requires that the
 682                  * output arrays have a buffer of up to 3 zeroes in front
 683                  * (at negative indices) for alignment purposes; we use 4
 684                  * to keep the data well-aligned.
 685                  */
 686                 if(0 != decoder->private_->output[i]) {
 687                         free(decoder->private_->output[i]-4);
 688                         decoder->private_->output[i] = 0;
 689                 }
 690                 if(0 != decoder->private_->residual_unaligned[i]) {
 691                         free(decoder->private_->residual_unaligned[i]);
 692                         decoder->private_->residual_unaligned[i] = decoder->private_->residual[i] = 0;
 693                 }
 694         }
 695         decoder->private_->output_capacity = 0;
 696         decoder->private_->output_channels = 0;
 697
 698 #if FLAC__HAS_OGG
 699         if(decoder->private_->is_ogg)
 700                 FLAC__ogg_decoder_aspect_finish(&decoder->protected_->ogg_decoder_aspect);
 701 #endif
 702
 703         if(0 != decoder->private_->file) {
 704                 if(decoder->private_->file != stdin)
 705                         fclose(decoder->private_->file);
 706                 decoder->private_->file = 0;
 707         }
 708
 709         if(decoder->private_->do_md5_checking) {
 710                 if(memcmp(decoder->private_->stream_info.data.stream_info.md5sum, decoder->private_->computed_md5sum, 16))
 711                         md5_failed = true;
 712         }
 713         decoder->private_->is_seeking = false;
 714
 715         set_defaults_(decoder);
 716
 717         decoder->protected_->state = FLAC__STREAM_DECODER_UNINITIALIZED;
 718
 719         return !md5_failed;
 720 }
 721
 722 FLAC_API FLAC__bool FLAC__stream_decoder_set_ogg_serial_number(FLAC__StreamDecoder *decoder, long value)
 723 {
 724         FLAC__ASSERT(0 != decoder);
 725         FLAC__ASSERT(0 != decoder->private_);
 726         FLAC__ASSERT(0 != decoder->protected_);
 727         if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
 728                 return false;
 729 #if FLAC__HAS_OGG
 730         /* can't check decoder->private_->is_ogg since that's not set until init time */
 731         FLAC__ogg_decoder_aspect_set_serial_number(&decoder->protected_->ogg_decoder_aspect, value);
 732         return true;
 733 #else
 734         (void)value;
 735         return false;
 736 #endif
 737 }
 738
 739 FLAC_API FLAC__bool FLAC__stream_decoder_set_md5_checking(FLAC__StreamDecoder *decoder, FLAC__bool value)
 740 {
 741         FLAC__ASSERT(0 != decoder);
 742         FLAC__ASSERT(0 != decoder->protected_);
 743         if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
 744                 return false;
 745         decoder->protected_->md5_checking = value;
 746         return true;
 747 }
 748
 749 FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_respond(FLAC__StreamDecoder *decoder, FLAC__MetadataType type)
 750 {
 751         FLAC__ASSERT(0 != decoder);
 752         FLAC__ASSERT(0 != decoder->private_);
 753         FLAC__ASSERT(0 != decoder->protected_);
 754         FLAC__ASSERT((unsigned)type <= FLAC__MAX_METADATA_TYPE_CODE);
 755         /* double protection */
 756         if((unsigned)type > FLAC__MAX_METADATA_TYPE_CODE)
 757                 return false;
 758         if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
 759                 return false;
 760         decoder->private_->metadata_filter[type] = true;
 761         if(type == FLAC__METADATA_TYPE_APPLICATION)
 762                 decoder->private_->metadata_filter_ids_count = 0;
 763         return true;
 764 }
 765
 766 FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_respond_application(FLAC__StreamDecoder *decoder, const FLAC__byte id[4])
 767 {
 768         FLAC__ASSERT(0 != decoder);
 769         FLAC__ASSERT(0 != decoder->private_);
 770         FLAC__ASSERT(0 != decoder->protected_);
 771         FLAC__ASSERT(0 != id);
 772         if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
 773                 return false;
 774
 775         if(decoder->private_->metadata_filter[FLAC__METADATA_TYPE_APPLICATION])
 776                 return true;
 777
 778         FLAC__ASSERT(0 != decoder->private_->metadata_filter_ids);
 779
 780         if(decoder->private_->metadata_filter_ids_count == decoder->private_->metadata_filter_ids_capacity) {
 781                 if(0 == (decoder->private_->metadata_filter_ids = safe_realloc_mul_2op_(decoder->private_->metadata_filter_ids, decoder->private_->metadata_filter_ids_capacity, /*times*/2))) {
 782                         decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
 783                         return false;
 784                 }
 785                 decoder->private_->metadata_filter_ids_capacity *= 2;
 786         }
 787
 788         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));
 789         decoder->private_->metadata_filter_ids_count++;
 790
 791         return true;
 792 }
 793
 794 FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_respond_all(FLAC__StreamDecoder *decoder)
 795 {
 796         unsigned i;
 797         FLAC__ASSERT(0 != decoder);
 798         FLAC__ASSERT(0 != decoder->private_);
 799         FLAC__ASSERT(0 != decoder->protected_);
 800         if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
 801                 return false;
 802         for(i = 0; i < sizeof(decoder->private_->metadata_filter) / sizeof(decoder->private_->metadata_filter[0]); i++)
 803                 decoder->private_->metadata_filter[i] = true;
 804         decoder->private_->metadata_filter_ids_count = 0;
 805         return true;
 806 }
 807
 808 FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_ignore(FLAC__StreamDecoder *decoder, FLAC__MetadataType type)
 809 {
 810         FLAC__ASSERT(0 != decoder);
 811         FLAC__ASSERT(0 != decoder->private_);
 812         FLAC__ASSERT(0 != decoder->protected_);
 813         FLAC__ASSERT((unsigned)type <= FLAC__MAX_METADATA_TYPE_CODE);
 814         /* double protection */
 815         if((unsigned)type > FLAC__MAX_METADATA_TYPE_CODE)
 816                 return false;
 817         if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
 818                 return false;
 819         decoder->private_->metadata_filter[type] = false;
 820         if(type == FLAC__METADATA_TYPE_APPLICATION)
 821                 decoder->private_->metadata_filter_ids_count = 0;
 822         return true;
 823 }
 824
 825 FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_ignore_application(FLAC__StreamDecoder *decoder, const FLAC__byte id[4])
 826 {
 827         FLAC__ASSERT(0 != decoder);
 828         FLAC__ASSERT(0 != decoder->private_);
 829         FLAC__ASSERT(0 != decoder->protected_);
 830         FLAC__ASSERT(0 != id);
 831         if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
 832                 return false;
 833
 834         if(!decoder->private_->metadata_filter[FLAC__METADATA_TYPE_APPLICATION])
 835                 return true;
 836
 837         FLAC__ASSERT(0 != decoder->private_->metadata_filter_ids);
 838
 839         if(decoder->private_->metadata_filter_ids_count == decoder->private_->metadata_filter_ids_capacity) {
 840                 if(0 == (decoder->private_->metadata_filter_ids = safe_realloc_mul_2op_(decoder->private_->metadata_filter_ids, decoder->private_->metadata_filter_ids_capacity, /*times*/2))) {
 841                         decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
 842                         return false;
 843                 }
 844                 decoder->private_->metadata_filter_ids_capacity *= 2;
 845         }
 846
 847         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));
 848         decoder->private_->metadata_filter_ids_count++;
 849
 850         return true;
 851 }
 852
 853 FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_ignore_all(FLAC__StreamDecoder *decoder)
 854 {
 855         FLAC__ASSERT(0 != decoder);
 856         FLAC__ASSERT(0 != decoder->private_);
 857         FLAC__ASSERT(0 != decoder->protected_);
 858         if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
 859                 return false;
 860         memset(decoder->private_->metadata_filter, 0, sizeof(decoder->private_->metadata_filter));
 861         decoder->private_->metadata_filter_ids_count = 0;
 862         return true;
 863 }
 864
 865 FLAC_API FLAC__StreamDecoderState FLAC__stream_decoder_get_state(const FLAC__StreamDecoder *decoder)
 866 {
 867         FLAC__ASSERT(0 != decoder);
 868         FLAC__ASSERT(0 != decoder->protected_);
 869         return decoder->protected_->state;
 870 }
 871
 872 FLAC_API const char *FLAC__stream_decoder_get_resolved_state_string(const FLAC__StreamDecoder *decoder)
 873 {
 874         return FLAC__StreamDecoderStateString[decoder->protected_->state];
 875 }
 876
 877 FLAC_API FLAC__bool FLAC__stream_decoder_get_md5_checking(const FLAC__StreamDecoder *decoder)
 878 {
 879         FLAC__ASSERT(0 != decoder);
 880         FLAC__ASSERT(0 != decoder->protected_);
 881         return decoder->protected_->md5_checking;
 882 }
 883
 884 FLAC_API FLAC__uint64 FLAC__stream_decoder_get_total_samples(const FLAC__StreamDecoder *decoder)
 885 {
 886         FLAC__ASSERT(0 != decoder);
 887         FLAC__ASSERT(0 != decoder->protected_);
 888         return decoder->private_->has_stream_info? decoder->private_->stream_info.data.stream_info.total_samples : 0;
 889 }
 890
 891 FLAC_API unsigned FLAC__stream_decoder_get_channels(const FLAC__StreamDecoder *decoder)
 892 {
 893         FLAC__ASSERT(0 != decoder);
 894         FLAC__ASSERT(0 != decoder->protected_);
 895         return decoder->protected_->channels;
 896 }
 897
 898 FLAC_API FLAC__ChannelAssignment FLAC__stream_decoder_get_channel_assignment(const FLAC__StreamDecoder *decoder)
 899 {
 900         FLAC__ASSERT(0 != decoder);
 901         FLAC__ASSERT(0 != decoder->protected_);
 902         return decoder->protected_->channel_assignment;
 903 }
 904
 905 FLAC_API unsigned FLAC__stream_decoder_get_bits_per_sample(const FLAC__StreamDecoder *decoder)
 906 {
 907         FLAC__ASSERT(0 != decoder);
 908         FLAC__ASSERT(0 != decoder->protected_);
 909         return decoder->protected_->bits_per_sample;
 910 }
 911
 912 FLAC_API unsigned FLAC__stream_decoder_get_sample_rate(const FLAC__StreamDecoder *decoder)
 913 {
 914         FLAC__ASSERT(0 != decoder);
 915         FLAC__ASSERT(0 != decoder->protected_);
 916         return decoder->protected_->sample_rate;
 917 }
 918
 919 FLAC_API unsigned FLAC__stream_decoder_get_blocksize(const FLAC__StreamDecoder *decoder)
 920 {
 921         FLAC__ASSERT(0 != decoder);
 922         FLAC__ASSERT(0 != decoder->protected_);
 923         return decoder->protected_->blocksize;
 924 }
 925
 926 FLAC_API FLAC__bool FLAC__stream_decoder_get_decode_position(const FLAC__StreamDecoder *decoder, FLAC__uint64 *position)
 927 {
 928         FLAC__ASSERT(0 != decoder);
 929         FLAC__ASSERT(0 != decoder->private_);
 930         FLAC__ASSERT(0 != position);
 931
 932 #if FLAC__HAS_OGG
 933         if(decoder->private_->is_ogg)
 934                 return false;
 935 #endif
 936         if(0 == decoder->private_->tell_callback)
 937                 return false;
 938         if(decoder->private_->tell_callback(decoder, position, decoder->private_->client_data) != FLAC__STREAM_DECODER_TELL_STATUS_OK)
 939                 return false;
 940         /* should never happen since all FLAC frames and metadata blocks are byte aligned, but check just in case */
 941         if(!FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input))
 942                 return false;
 943         FLAC__ASSERT(*position >= FLAC__stream_decoder_get_input_bytes_unconsumed(decoder));
 944         *position -= FLAC__stream_decoder_get_input_bytes_unconsumed(decoder);
 945         return true;
 946 }
 947
 948 FLAC_API FLAC__bool FLAC__stream_decoder_flush(FLAC__StreamDecoder *decoder)
 949 {
 950         FLAC__ASSERT(0 != decoder);
 951         FLAC__ASSERT(0 != decoder->private_);
 952         FLAC__ASSERT(0 != decoder->protected_);
 953
 954         decoder->private_->samples_decoded = 0;
 955         decoder->private_->do_md5_checking = false;
 956
 957 #if FLAC__HAS_OGG
 958         if(decoder->private_->is_ogg)
 959                 FLAC__ogg_decoder_aspect_flush(&decoder->protected_->ogg_decoder_aspect);
 960 #endif
 961
 962         if(!FLAC__bitreader_clear(decoder->private_->input)) {
 963                 decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
 964                 return false;
 965         }
 966         decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
 967
 968         return true;
 969 }
 970
 971 FLAC_API FLAC__bool FLAC__stream_decoder_reset(FLAC__StreamDecoder *decoder)
 972 {
 973         FLAC__ASSERT(0 != decoder);
 974         FLAC__ASSERT(0 != decoder->private_);
 975         FLAC__ASSERT(0 != decoder->protected_);
 976
 977         if(!FLAC__stream_decoder_flush(decoder)) {
 978                 /* above call sets the state for us */
 979                 return false;
 980         }
 981
 982 #if FLAC__HAS_OGG
 983         /*@@@ could go in !internal_reset_hack block below */
 984         if(decoder->private_->is_ogg)
 985                 FLAC__ogg_decoder_aspect_reset(&decoder->protected_->ogg_decoder_aspect);
 986 #endif
 987
 988         /* Rewind if necessary.  If FLAC__stream_decoder_init() is calling us,
 989          * (internal_reset_hack) don't try to rewind since we are already at
 990          * the beginning of the stream and don't want to fail if the input is
 991          * not seekable.
 992          */
 993         if(!decoder->private_->internal_reset_hack) {
 994                 if(decoder->private_->file == stdin)
 995                         return false; /* can't rewind stdin, reset fails */
 996                 if(decoder->private_->seek_callback && decoder->private_->seek_callback(decoder, 0, decoder->private_->client_data) == FLAC__STREAM_DECODER_SEEK_STATUS_ERROR)
 997                         return false; /* seekable and seek fails, reset fails */
 998         }
 999         else
1000                 decoder->private_->internal_reset_hack = false;
1001
1002         decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_METADATA;
1003
1004         decoder->private_->has_stream_info = false;
1005         if(decoder->private_->has_seek_table && 0 != decoder->private_->seek_table.data.seek_table.points) {
1006                 free(decoder->private_->seek_table.data.seek_table.points);
1007                 decoder->private_->seek_table.data.seek_table.points = 0;
1008                 decoder->private_->has_seek_table = false;
1009         }
1010         decoder->private_->do_md5_checking = decoder->protected_->md5_checking;
1011         /*
1012          * This goes in reset() and not flush() because according to the spec, a
1013          * fixed-blocksize stream must stay that way through the whole stream.
1014          */
1015         decoder->private_->fixed_block_size = decoder->private_->next_fixed_block_size = 0;
1016
1017         /* We initialize the FLAC__MD5Context even though we may never use it.  This
1018          * is because md5 checking may be turned on to start and then turned off if
1019          * a seek occurs.  So we init the context here and finalize it in
1020          * FLAC__stream_decoder_finish() to make sure things are always cleaned up
1021          * properly.
1022          */
1023         FLAC__MD5Init(&decoder->private_->md5context);
1024
1025         decoder->private_->first_frame_offset = 0;
1026         decoder->private_->unparseable_frame_count = 0;
1027
1028         return true;
1029 }
1030
1031 FLAC_API FLAC__bool FLAC__stream_decoder_process_single(FLAC__StreamDecoder *decoder)
1032 {
1033         FLAC__bool got_a_frame;
1034         FLAC__ASSERT(0 != decoder);
1035         FLAC__ASSERT(0 != decoder->protected_);
1036
1037         while(1) {
1038                 switch(decoder->protected_->state) {
1039                         case FLAC__STREAM_DECODER_SEARCH_FOR_METADATA:
1040                                 if(!find_metadata_(decoder))
1041                                         return false; /* above function sets the status for us */
1042                                 break;
1043                         case FLAC__STREAM_DECODER_READ_METADATA:
1044                                 if(!read_metadata_(decoder))
1045                                         return false; /* above function sets the status for us */
1046                                 else
1047                                         return true;
1048                         case FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC:
1049                                 if(!frame_sync_(decoder))
1050                                         return true; /* above function sets the status for us */
1051                                 break;
1052                         case FLAC__STREAM_DECODER_READ_FRAME:
1053                                 if(!read_frame_(decoder, &got_a_frame, /*do_full_decode=*/true))
1054                                         return false; /* above function sets the status for us */
1055                                 if(got_a_frame)
1056                                         return true; /* above function sets the status for us */
1057                                 break;
1058                         case FLAC__STREAM_DECODER_END_OF_STREAM:
1059                         case FLAC__STREAM_DECODER_ABORTED:
1060                                 return true;
1061                         default:
1062                                 FLAC__ASSERT(0);
1063                                 return false;
1064                 }
1065         }
1066 }
1067
1068 FLAC_API FLAC__bool FLAC__stream_decoder_process_until_end_of_metadata(FLAC__StreamDecoder *decoder)
1069 {
1070         FLAC__ASSERT(0 != decoder);
1071         FLAC__ASSERT(0 != decoder->protected_);
1072
1073         while(1) {
1074                 switch(decoder->protected_->state) {
1075                         case FLAC__STREAM_DECODER_SEARCH_FOR_METADATA:
1076                                 if(!find_metadata_(decoder))
1077                                         return false; /* above function sets the status for us */
1078                                 break;
1079                         case FLAC__STREAM_DECODER_READ_METADATA:
1080                                 if(!read_metadata_(decoder))
1081                                         return false; /* above function sets the status for us */
1082                                 break;
1083                         case FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC:
1084                         case FLAC__STREAM_DECODER_READ_FRAME:
1085                         case FLAC__STREAM_DECODER_END_OF_STREAM:
1086                         case FLAC__STREAM_DECODER_ABORTED:
1087                                 return true;
1088                         default:
1089                                 FLAC__ASSERT(0);
1090                                 return false;
1091                 }
1092         }
1093 }
1094
1095 FLAC_API FLAC__bool FLAC__stream_decoder_process_until_end_of_stream(FLAC__StreamDecoder *decoder)
1096 {
1097         FLAC__bool dummy;
1098         FLAC__ASSERT(0 != decoder);
1099         FLAC__ASSERT(0 != decoder->protected_);
1100
1101         while(1) {
1102                 switch(decoder->protected_->state) {
1103                         case FLAC__STREAM_DECODER_SEARCH_FOR_METADATA:
1104                                 if(!find_metadata_(decoder))
1105                                         return false; /* above function sets the status for us */
1106                                 break;
1107                         case FLAC__STREAM_DECODER_READ_METADATA:
1108                                 if(!read_metadata_(decoder))
1109                                         return false; /* above function sets the status for us */
1110                                 break;
1111                         case FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC:
1112                                 if(!frame_sync_(decoder))
1113                                         return true; /* above function sets the status for us */
1114                                 break;
1115                         case FLAC__STREAM_DECODER_READ_FRAME:
1116                                 if(!read_frame_(decoder, &dummy, /*do_full_decode=*/true))
1117                                         return false; /* above function sets the status for us */
1118                                 break;
1119                         case FLAC__STREAM_DECODER_END_OF_STREAM:
1120                         case FLAC__STREAM_DECODER_ABORTED:
1121                                 return true;
1122                         default:
1123                                 FLAC__ASSERT(0);
1124                                 return false;
1125                 }
1126         }
1127 }
1128
1129 FLAC_API FLAC__bool FLAC__stream_decoder_skip_single_frame(FLAC__StreamDecoder *decoder)
1130 {
1131         FLAC__bool got_a_frame;
1132         FLAC__ASSERT(0 != decoder);
1133         FLAC__ASSERT(0 != decoder->protected_);
1134
1135         while(1) {
1136                 switch(decoder->protected_->state) {
1137                         case FLAC__STREAM_DECODER_SEARCH_FOR_METADATA:
1138                         case FLAC__STREAM_DECODER_READ_METADATA:
1139                                 return false; /* above function sets the status for us */
1140                         case FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC:
1141                                 if(!frame_sync_(decoder))
1142                                         return true; /* above function sets the status for us */
1143                                 break;
1144                         case FLAC__STREAM_DECODER_READ_FRAME:
1145                                 if(!read_frame_(decoder, &got_a_frame, /*do_full_decode=*/false))
1146                                         return false; /* above function sets the status for us */
1147                                 if(got_a_frame)
1148                                         return true; /* above function sets the status for us */
1149                                 break;
1150                         case FLAC__STREAM_DECODER_END_OF_STREAM:
1151                         case FLAC__STREAM_DECODER_ABORTED:
1152                                 return true;
1153                         default:
1154                                 FLAC__ASSERT(0);
1155                                 return false;
1156                 }
1157         }
1158 }
1159
1160 FLAC_API FLAC__bool FLAC__stream_decoder_seek_absolute(FLAC__StreamDecoder *decoder, FLAC__uint64 sample)
1161 {
1162         FLAC__uint64 length;
1163
1164         FLAC__ASSERT(0 != decoder);
1165
1166         if(
1167                 decoder->protected_->state != FLAC__STREAM_DECODER_SEARCH_FOR_METADATA &&
1168                 decoder->protected_->state != FLAC__STREAM_DECODER_READ_METADATA &&
1169                 decoder->protected_->state != FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC &&
1170                 decoder->protected_->state != FLAC__STREAM_DECODER_READ_FRAME &&
1171                 decoder->protected_->state != FLAC__STREAM_DECODER_END_OF_STREAM
1172         )
1173                 return false;
1174
1175         if(0 == decoder->private_->seek_callback)
1176                 return false;
1177
1178         FLAC__ASSERT(decoder->private_->seek_callback);
1179         FLAC__ASSERT(decoder->private_->tell_callback);
1180         FLAC__ASSERT(decoder->private_->length_callback);
1181         FLAC__ASSERT(decoder->private_->eof_callback);
1182
1183         if(FLAC__stream_decoder_get_total_samples(decoder) > 0 && sample >= FLAC__stream_decoder_get_total_samples(decoder))
1184                 return false;
1185
1186         decoder->private_->is_seeking = true;
1187
1188         /* turn off md5 checking if a seek is attempted */
1189         decoder->private_->do_md5_checking = false;
1190
1191         /* 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) */
1192         if(decoder->private_->length_callback(decoder, &length, decoder->private_->client_data) != FLAC__STREAM_DECODER_LENGTH_STATUS_OK) {
1193                 decoder->private_->is_seeking = false;
1194                 return false;
1195         }
1196
1197         /* if we haven't finished processing the metadata yet, do that so we have the STREAMINFO, SEEK_TABLE, and first_frame_offset */
1198         if(
1199                 decoder->protected_->state == FLAC__STREAM_DECODER_SEARCH_FOR_METADATA ||
1200                 decoder->protected_->state == FLAC__STREAM_DECODER_READ_METADATA
1201         ) {
1202                 if(!FLAC__stream_decoder_process_until_end_of_metadata(decoder)) {
1203                         /* above call sets the state for us */
1204                         decoder->private_->is_seeking = false;
1205                         return false;
1206                 }
1207                 /* check this again in case we didn't know total_samples the first time */
1208                 if(FLAC__stream_decoder_get_total_samples(decoder) > 0 && sample >= FLAC__stream_decoder_get_total_samples(decoder)) {
1209                         decoder->private_->is_seeking = false;
1210                         return false;
1211                 }
1212         }
1213
1214         {
1215                 const FLAC__bool ok =
1216 #if FLAC__HAS_OGG
1217                         decoder->private_->is_ogg?
1218                         seek_to_absolute_sample_ogg_(decoder, length, sample) :
1219 #endif
1220                         seek_to_absolute_sample_(decoder, length, sample)
1221                 ;
1222                 decoder->private_->is_seeking = false;
1223                 return ok;
1224         }
1225 }
1226
1227 /***********************************************************************
1228  *
1229  * Protected class methods
1230  *
1231  ***********************************************************************/
1232
1233 unsigned FLAC__stream_decoder_get_input_bytes_unconsumed(const FLAC__StreamDecoder *decoder)
1234 {
1235         FLAC__ASSERT(0 != decoder);
1236         FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));
1237         FLAC__ASSERT(!(FLAC__bitreader_get_input_bits_unconsumed(decoder->private_->input) & 7));
1238         return FLAC__bitreader_get_input_bits_unconsumed(decoder->private_->input) / 8;
1239 }
1240
1241 /***********************************************************************
1242  *
1243  * Private class methods
1244  *
1245  ***********************************************************************/
1246
1247 void set_defaults_(FLAC__StreamDecoder *decoder)
1248 {
1249 #if FLAC__HAS_OGG
1250         decoder->private_->is_ogg = false;
1251 #endif
1252         decoder->private_->read_callback = 0;
1253         decoder->private_->seek_callback = 0;
1254         decoder->private_->tell_callback = 0;
1255         decoder->private_->length_callback = 0;
1256         decoder->private_->eof_callback = 0;
1257         decoder->private_->write_callback = 0;
1258         decoder->private_->metadata_callback = 0;
1259         decoder->private_->error_callback = 0;
1260         decoder->private_->client_data = 0;
1261
1262         memset(decoder->private_->metadata_filter, 0, sizeof(decoder->private_->metadata_filter));
1263         decoder->private_->metadata_filter[FLAC__METADATA_TYPE_STREAMINFO] = true;
1264         decoder->private_->metadata_filter_ids_count = 0;
1265
1266         decoder->protected_->md5_checking = false;
1267
1268 #if FLAC__HAS_OGG
1269         FLAC__ogg_decoder_aspect_set_defaults(&decoder->protected_->ogg_decoder_aspect);
1270 #endif
1271 }
1272
1273 /*
1274  * This will forcibly set stdin to binary mode (for OSes that require it)
1275  */
1276 FILE *get_binary_stdin_(void)
1277 {
1278         /* if something breaks here it is probably due to the presence or
1279          * absence of an underscore before the identifiers 'setmode',
1280          * 'fileno', and/or 'O_BINARY'; check your system header files.
1281          */
1282 #if defined _MSC_VER || defined __MINGW32__
1283         _setmode(_fileno(stdin), _O_BINARY);
1284 #elif defined __CYGWIN__
1285         /* almost certainly not needed for any modern Cygwin, but let's be safe... */
1286         setmode(_fileno(stdin), _O_BINARY);
1287 #elif defined __EMX__
1288         setmode(fileno(stdin), O_BINARY);
1289 #endif
1290
1291         return stdin;
1292 }
1293
1294 FLAC__bool allocate_output_(FLAC__StreamDecoder *decoder, unsigned size, unsigned channels)
1295 {
1296         unsigned i;
1297         FLAC__int32 *tmp;
1298
1299         if(size <= decoder->private_->output_capacity && channels <= decoder->private_->output_channels)
1300                 return true;
1301
1302         /* simply using realloc() is not practical because the number of channels may change mid-stream */
1303
1304         for(i = 0; i < FLAC__MAX_CHANNELS; i++) {
1305                 if(0 != decoder->private_->output[i]) {
1306                         free(decoder->private_->output[i]-4);
1307                         decoder->private_->output[i] = 0;
1308                 }
1309                 if(0 != decoder->private_->residual_unaligned[i]) {
1310                         free(decoder->private_->residual_unaligned[i]);
1311                         decoder->private_->residual_unaligned[i] = decoder->private_->residual[i] = 0;
1312                 }
1313         }
1314
1315         for(i = 0; i < channels; i++) {
1316                 /* WATCHOUT:
1317                  * FLAC__lpc_restore_signal_asm_ia32_mmx() requires that the
1318                  * output arrays have a buffer of up to 3 zeroes in front
1319                  * (at negative indices) for alignment purposes; we use 4
1320                  * to keep the data well-aligned.
1321                  */
1322                 tmp = safe_malloc_muladd2_(sizeof(FLAC__int32), /*times (*/size, /*+*/4/*)*/);
1323                 if(tmp == 0) {
1324                         decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1325                         return false;
1326                 }
1327                 memset(tmp, 0, sizeof(FLAC__int32)*4);
1328                 decoder->private_->output[i] = tmp + 4;
1329
1330                 /* WATCHOUT:
1331                  * minimum of quadword alignment for PPC vector optimizations is REQUIRED:
1332                  */
1333                 if(!FLAC__memory_alloc_aligned_int32_array(size, &decoder->private_->residual_unaligned[i], &decoder->private_->residual[i])) {
1334                         decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1335                         return false;
1336                 }
1337         }
1338
1339         decoder->private_->output_capacity = size;
1340         decoder->private_->output_channels = channels;
1341
1342         return true;
1343 }
1344
1345 FLAC__bool has_id_filtered_(FLAC__StreamDecoder *decoder, FLAC__byte *id)
1346 {
1347         size_t i;
1348
1349         FLAC__ASSERT(0 != decoder);
1350         FLAC__ASSERT(0 != decoder->private_);
1351
1352         for(i = 0; i < decoder->private_->metadata_filter_ids_count; i++)
1353                 if(0 == memcmp(decoder->private_->metadata_filter_ids + i * (FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8), id, (FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8)))
1354                         return true;
1355
1356         return false;
1357 }
1358
1359 FLAC__bool find_metadata_(FLAC__StreamDecoder *decoder)
1360 {
1361         FLAC__uint32 x;
1362         unsigned i, id;
1363         FLAC__bool first = true;
1364
1365         FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));
1366
1367         for(i = id = 0; i < 4; ) {
1368                 if(decoder->private_->cached) {
1369                         x = (FLAC__uint32)decoder->private_->lookahead;
1370                         decoder->private_->cached = false;
1371                 }
1372                 else {
1373                         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
1374                                 return false; /* read_callback_ sets the state for us */
1375                 }
1376                 if(x == FLAC__STREAM_SYNC_STRING[i]) {
1377                         first = true;
1378                         i++;
1379                         id = 0;
1380                         continue;
1381                 }
1382                 if(x == ID3V2_TAG_[id]) {
1383                         id++;
1384                         i = 0;
1385                         if(id == 3) {
1386                                 if(!skip_id3v2_tag_(decoder))
1387                                         return false; /* skip_id3v2_tag_ sets the state for us */
1388                         }
1389                         continue;
1390                 }
1391                 id = 0;
1392                 if(x == 0xff) { /* MAGIC NUMBER for the first 8 frame sync bits */
1393                         decoder->private_->header_warmup[0] = (FLAC__byte)x;
1394                         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
1395                                 return false; /* read_callback_ sets the state for us */
1396
1397                         /* 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 */
1398                         /* else we have to check if the second byte is the end of a sync code */
1399                         if(x == 0xff) { /* MAGIC NUMBER for the first 8 frame sync bits */
1400                                 decoder->private_->lookahead = (FLAC__byte)x;
1401                                 decoder->private_->cached = true;
1402                         }
1403                         else if(x >> 1 == 0x7c) { /* MAGIC NUMBER for the last 6 sync bits and reserved 7th bit */
1404                                 decoder->private_->header_warmup[1] = (FLAC__byte)x;
1405                                 decoder->protected_->state = FLAC__STREAM_DECODER_READ_FRAME;
1406                                 return true;
1407                         }
1408                 }
1409                 i = 0;
1410                 if(first) {
1411                         send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
1412                         first = false;
1413                 }
1414         }
1415
1416         decoder->protected_->state = FLAC__STREAM_DECODER_READ_METADATA;
1417         return true;
1418 }
1419
1420 FLAC__bool read_metadata_(FLAC__StreamDecoder *decoder)
1421 {
1422         FLAC__bool is_last;
1423         FLAC__uint32 i, x, type, length;
1424
1425         FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));
1426
1427         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_IS_LAST_LEN))
1428                 return false; /* read_callback_ sets the state for us */
1429         is_last = x? true : false;
1430
1431         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &type, FLAC__STREAM_METADATA_TYPE_LEN))
1432                 return false; /* read_callback_ sets the state for us */
1433
1434         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &length, FLAC__STREAM_METADATA_LENGTH_LEN))
1435                 return false; /* read_callback_ sets the state for us */
1436
1437         if(type == FLAC__METADATA_TYPE_STREAMINFO) {
1438                 if(!read_metadata_streaminfo_(decoder, is_last, length))
1439                         return false;
1440
1441                 decoder->private_->has_stream_info = true;
1442                 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))
1443                         decoder->private_->do_md5_checking = false;
1444                 if(!decoder->private_->is_seeking && decoder->private_->metadata_filter[FLAC__METADATA_TYPE_STREAMINFO] && decoder->private_->metadata_callback)
1445                         decoder->private_->metadata_callback(decoder, &decoder->private_->stream_info, decoder->private_->client_data);
1446         }
1447         else if(type == FLAC__METADATA_TYPE_SEEKTABLE) {
1448                 if(!read_metadata_seektable_(decoder, is_last, length))
1449                         return false;
1450
1451                 decoder->private_->has_seek_table = true;
1452                 if(!decoder->private_->is_seeking && decoder->private_->metadata_filter[FLAC__METADATA_TYPE_SEEKTABLE] && decoder->private_->metadata_callback)
1453                         decoder->private_->metadata_callback(decoder, &decoder->private_->seek_table, decoder->private_->client_data);
1454         }
1455         else {
1456                 FLAC__bool skip_it = !decoder->private_->metadata_filter[type];
1457                 unsigned real_length = length;
1458                 FLAC__StreamMetadata block;
1459
1460                 block.is_last = is_last;
1461                 block.type = (FLAC__MetadataType)type;
1462                 block.length = length;
1463
1464                 if(type == FLAC__METADATA_TYPE_APPLICATION) {
1465                         if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, block.data.application.id, FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8))
1466                                 return false; /* read_callback_ sets the state for us */
1467
1468                         if(real_length < FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8) { /* underflow check */
1469                                 decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;/*@@@@@@ maybe wrong error? need to resync?*/
1470                                 return false;
1471                         }
1472
1473                         real_length -= FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8;
1474
1475                         if(decoder->private_->metadata_filter_ids_count > 0 && has_id_filtered_(decoder, block.data.application.id))
1476                                 skip_it = !skip_it;
1477                 }
1478
1479                 if(skip_it) {
1480                         if(!FLAC__bitreader_skip_byte_block_aligned_no_crc(decoder->private_->input, real_length))
1481                                 return false; /* read_callback_ sets the state for us */
1482                 }
1483                 else {
1484                         switch(type) {
1485                                 case FLAC__METADATA_TYPE_PADDING:
1486                                         /* skip the padding bytes */
1487                                         if(!FLAC__bitreader_skip_byte_block_aligned_no_crc(decoder->private_->input, real_length))
1488                                                 return false; /* read_callback_ sets the state for us */
1489                                         break;
1490                                 case FLAC__METADATA_TYPE_APPLICATION:
1491                                         /* remember, we read the ID already */
1492                                         if(real_length > 0) {
1493                                                 if(0 == (block.data.application.data = malloc(real_length))) {
1494                                                         decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1495                                                         return false;
1496                                                 }
1497                                                 if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, block.data.application.data, real_length))
1498                                                         return false; /* read_callback_ sets the state for us */
1499                                         }
1500                                         else
1501                                                 block.data.application.data = 0;
1502                                         break;
1503                                 case FLAC__METADATA_TYPE_VORBIS_COMMENT:
1504                                         if(!read_metadata_vorbiscomment_(decoder, &block.data.vorbis_comment))
1505                                                 return false;
1506                                         break;
1507                                 case FLAC__METADATA_TYPE_CUESHEET:
1508                                         if(!read_metadata_cuesheet_(decoder, &block.data.cue_sheet))
1509                                                 return false;
1510                                         break;
1511                                 case FLAC__METADATA_TYPE_PICTURE:
1512                                         if(!read_metadata_picture_(decoder, &block.data.picture))
1513                                                 return false;
1514                                         break;
1515                                 case FLAC__METADATA_TYPE_STREAMINFO:
1516                                 case FLAC__METADATA_TYPE_SEEKTABLE:
1517                                         FLAC__ASSERT(0);
1518                                         break;
1519                                 default:
1520                                         if(real_length > 0) {
1521                                                 if(0 == (block.data.unknown.data = malloc(real_length))) {
1522                                                         decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1523                                                         return false;
1524                                                 }
1525                                                 if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, block.data.unknown.data, real_length))
1526                                                         return false; /* read_callback_ sets the state for us */
1527                                         }
1528                                         else
1529                                                 block.data.unknown.data = 0;
1530                                         break;
1531                         }
1532                         if(!decoder->private_->is_seeking && decoder->private_->metadata_callback)
1533                                 decoder->private_->metadata_callback(decoder, &block, decoder->private_->client_data);
1534
1535                         /* now we have to free any malloc()ed data in the block */
1536                         switch(type) {
1537                                 case FLAC__METADATA_TYPE_PADDING:
1538                                         break;
1539                                 case FLAC__METADATA_TYPE_APPLICATION:
1540                                         if(0 != block.data.application.data)
1541                                                 free(block.data.application.data);
1542                                         break;
1543                                 case FLAC__METADATA_TYPE_VORBIS_COMMENT:
1544                                         if(0 != block.data.vorbis_comment.vendor_string.entry)
1545                                                 free(block.data.vorbis_comment.vendor_string.entry);
1546                                         if(block.data.vorbis_comment.num_comments > 0)
1547                                                 for(i = 0; i < block.data.vorbis_comment.num_comments; i++)
1548                                                         if(0 != block.data.vorbis_comment.comments[i].entry)
1549                                                                 free(block.data.vorbis_comment.comments[i].entry);
1550                                         if(0 != block.data.vorbis_comment.comments)
1551                                                 free(block.data.vorbis_comment.comments);
1552                                         break;
1553                                 case FLAC__METADATA_TYPE_CUESHEET:
1554                                         if(block.data.cue_sheet.num_tracks > 0)
1555                                                 for(i = 0; i < block.data.cue_sheet.num_tracks; i++)
1556                                                         if(0 != block.data.cue_sheet.tracks[i].indices)
1557                                                                 free(block.data.cue_sheet.tracks[i].indices);
1558                                         if(0 != block.data.cue_sheet.tracks)
1559                                                 free(block.data.cue_sheet.tracks);
1560                                         break;
1561                                 case FLAC__METADATA_TYPE_PICTURE:
1562                                         if(0 != block.data.picture.mime_type)
1563                                                 free(block.data.picture.mime_type);
1564                                         if(0 != block.data.picture.description)
1565                                                 free(block.data.picture.description);
1566                                         if(0 != block.data.picture.data)
1567                                                 free(block.data.picture.data);
1568                                         break;
1569                                 case FLAC__METADATA_TYPE_STREAMINFO:
1570                                 case FLAC__METADATA_TYPE_SEEKTABLE:
1571                                         FLAC__ASSERT(0);
1572                                 default:
1573                                         if(0 != block.data.unknown.data)
1574                                                 free(block.data.unknown.data);
1575                                         break;
1576                         }
1577                 }
1578         }
1579
1580         if(is_last) {
1581                 /* if this fails, it's OK, it's just a hint for the seek routine */
1582                 if(!FLAC__stream_decoder_get_decode_position(decoder, &decoder->private_->first_frame_offset))
1583                         decoder->private_->first_frame_offset = 0;
1584                 decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
1585         }
1586
1587         return true;
1588 }
1589
1590 FLAC__bool read_metadata_streaminfo_(FLAC__StreamDecoder *decoder, FLAC__bool is_last, unsigned length)
1591 {
1592         FLAC__uint32 x;
1593         unsigned bits, used_bits = 0;
1594
1595         FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));
1596
1597         decoder->private_->stream_info.type = FLAC__METADATA_TYPE_STREAMINFO;
1598         decoder->private_->stream_info.is_last = is_last;
1599         decoder->private_->stream_info.length = length;
1600
1601         bits = FLAC__STREAM_METADATA_STREAMINFO_MIN_BLOCK_SIZE_LEN;
1602         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, bits))
1603                 return false; /* read_callback_ sets the state for us */
1604         decoder->private_->stream_info.data.stream_info.min_blocksize = x;
1605         used_bits += bits;
1606
1607         bits = FLAC__STREAM_METADATA_STREAMINFO_MAX_BLOCK_SIZE_LEN;
1608         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_MAX_BLOCK_SIZE_LEN))
1609                 return false; /* read_callback_ sets the state for us */
1610         decoder->private_->stream_info.data.stream_info.max_blocksize = x;
1611         used_bits += bits;
1612
1613         bits = FLAC__STREAM_METADATA_STREAMINFO_MIN_FRAME_SIZE_LEN;
1614         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_MIN_FRAME_SIZE_LEN))
1615                 return false; /* read_callback_ sets the state for us */
1616         decoder->private_->stream_info.data.stream_info.min_framesize = x;
1617         used_bits += bits;
1618
1619         bits = FLAC__STREAM_METADATA_STREAMINFO_MAX_FRAME_SIZE_LEN;
1620         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_MAX_FRAME_SIZE_LEN))
1621                 return false; /* read_callback_ sets the state for us */
1622         decoder->private_->stream_info.data.stream_info.max_framesize = x;
1623         used_bits += bits;
1624
1625         bits = FLAC__STREAM_METADATA_STREAMINFO_SAMPLE_RATE_LEN;
1626         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_SAMPLE_RATE_LEN))
1627                 return false; /* read_callback_ sets the state for us */
1628         decoder->private_->stream_info.data.stream_info.sample_rate = x;
1629         used_bits += bits;
1630
1631         bits = FLAC__STREAM_METADATA_STREAMINFO_CHANNELS_LEN;
1632         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_CHANNELS_LEN))
1633                 return false; /* read_callback_ sets the state for us */
1634         decoder->private_->stream_info.data.stream_info.channels = x+1;
1635         used_bits += bits;
1636
1637         bits = FLAC__STREAM_METADATA_STREAMINFO_BITS_PER_SAMPLE_LEN;
1638         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_BITS_PER_SAMPLE_LEN))
1639                 return false; /* read_callback_ sets the state for us */
1640         decoder->private_->stream_info.data.stream_info.bits_per_sample = x+1;
1641         used_bits += bits;
1642
1643         bits = FLAC__STREAM_METADATA_STREAMINFO_TOTAL_SAMPLES_LEN;
1644         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))
1645                 return false; /* read_callback_ sets the state for us */
1646         used_bits += bits;
1647
1648         if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, decoder->private_->stream_info.data.stream_info.md5sum, 16))
1649                 return false; /* read_callback_ sets the state for us */
1650         used_bits += 16*8;
1651
1652         /* skip the rest of the block */
1653         FLAC__ASSERT(used_bits % 8 == 0);
1654         length -= (used_bits / 8);
1655         if(!FLAC__bitreader_skip_byte_block_aligned_no_crc(decoder->private_->input, length))
1656                 return false; /* read_callback_ sets the state for us */
1657
1658         return true;
1659 }
1660
1661 FLAC__bool read_metadata_seektable_(FLAC__StreamDecoder *decoder, FLAC__bool is_last, unsigned length)
1662 {
1663         FLAC__uint32 i, x;
1664         FLAC__uint64 xx;
1665
1666         FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));
1667
1668         decoder->private_->seek_table.type = FLAC__METADATA_TYPE_SEEKTABLE;
1669         decoder->private_->seek_table.is_last = is_last;
1670         decoder->private_->seek_table.length = length;
1671
1672         decoder->private_->seek_table.data.seek_table.num_points = length / FLAC__STREAM_METADATA_SEEKPOINT_LENGTH;
1673
1674         /* use realloc since we may pass through here several times (e.g. after seeking) */
1675         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)))) {
1676                 decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1677                 return false;
1678         }
1679         for(i = 0; i < decoder->private_->seek_table.data.seek_table.num_points; i++) {
1680                 if(!FLAC__bitreader_read_raw_uint64(decoder->private_->input, &xx, FLAC__STREAM_METADATA_SEEKPOINT_SAMPLE_NUMBER_LEN))
1681                         return false; /* read_callback_ sets the state for us */
1682                 decoder->private_->seek_table.data.seek_table.points[i].sample_number = xx;
1683
1684                 if(!FLAC__bitreader_read_raw_uint64(decoder->private_->input, &xx, FLAC__STREAM_METADATA_SEEKPOINT_STREAM_OFFSET_LEN))
1685                         return false; /* read_callback_ sets the state for us */
1686                 decoder->private_->seek_table.data.seek_table.points[i].stream_offset = xx;
1687
1688                 if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_SEEKPOINT_FRAME_SAMPLES_LEN))
1689                         return false; /* read_callback_ sets the state for us */
1690                 decoder->private_->seek_table.data.seek_table.points[i].frame_samples = x;
1691         }
1692         length -= (decoder->private_->seek_table.data.seek_table.num_points * FLAC__STREAM_METADATA_SEEKPOINT_LENGTH);
1693         /* if there is a partial point left, skip over it */
1694         if(length > 0) {
1695                 /*@@@ do a send_error_to_client_() here?  there's an argument for either way */
1696                 if(!FLAC__bitreader_skip_byte_block_aligned_no_crc(decoder->private_->input, length))
1697                         return false; /* read_callback_ sets the state for us */
1698         }
1699
1700         return true;
1701 }
1702
1703 FLAC__bool read_metadata_vorbiscomment_(FLAC__StreamDecoder *decoder, FLAC__StreamMetadata_VorbisComment *obj)
1704 {
1705         FLAC__uint32 i;
1706
1707         FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));
1708
1709         /* read vendor string */
1710         FLAC__ASSERT(FLAC__STREAM_METADATA_VORBIS_COMMENT_ENTRY_LENGTH_LEN == 32);
1711         if(!FLAC__bitreader_read_uint32_little_endian(decoder->private_->input, &obj->vendor_string.length))
1712                 return false; /* read_callback_ sets the state for us */
1713         if(obj->vendor_string.length > 0) {
1714                 if(0 == (obj->vendor_string.entry = safe_malloc_add_2op_(obj->vendor_string.length, /*+*/1))) {
1715                         decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1716                         return false;
1717                 }
1718                 if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, obj->vendor_string.entry, obj->vendor_string.length))
1719                         return false; /* read_callback_ sets the state for us */
1720                 obj->vendor_string.entry[obj->vendor_string.length] = '\0';
1721         }
1722         else
1723                 obj->vendor_string.entry = 0;
1724
1725         /* read num comments */
1726         FLAC__ASSERT(FLAC__STREAM_METADATA_VORBIS_COMMENT_NUM_COMMENTS_LEN == 32);
1727         if(!FLAC__bitreader_read_uint32_little_endian(decoder->private_->input, &obj->num_comments))
1728                 return false; /* read_callback_ sets the state for us */
1729
1730         /* read comments */
1731         if(obj->num_comments > 0) {
1732                 if(0 == (obj->comments = safe_malloc_mul_2op_(obj->num_comments, /*times*/sizeof(FLAC__StreamMetadata_VorbisComment_Entry)))) {
1733                         decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1734                         return false;
1735                 }
1736                 for(i = 0; i < obj->num_comments; i++) {
1737                         FLAC__ASSERT(FLAC__STREAM_METADATA_VORBIS_COMMENT_ENTRY_LENGTH_LEN == 32);
1738                         if(!FLAC__bitreader_read_uint32_little_endian(decoder->private_->input, &obj->comments[i].length))
1739                                 return false; /* read_callback_ sets the state for us */
1740                         if(obj->comments[i].length > 0) {
1741                                 if(0 == (obj->comments[i].entry = safe_malloc_add_2op_(obj->comments[i].length, /*+*/1))) {
1742                                         decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1743                                         return false;
1744                                 }
1745                                 if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, obj->comments[i].entry, obj->comments[i].length))
1746                                         return false; /* read_callback_ sets the state for us */
1747                                 obj->comments[i].entry[obj->comments[i].length] = '\0';
1748                         }
1749                         else
1750                                 obj->comments[i].entry = 0;
1751                 }
1752         }
1753         else {
1754                 obj->comments = 0;
1755         }
1756
1757         return true;
1758 }
1759
1760 FLAC__bool read_metadata_cuesheet_(FLAC__StreamDecoder *decoder, FLAC__StreamMetadata_CueSheet *obj)
1761 {
1762         FLAC__uint32 i, j, x;
1763
1764         FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));
1765
1766         memset(obj, 0, sizeof(FLAC__StreamMetadata_CueSheet));
1767
1768         FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_MEDIA_CATALOG_NUMBER_LEN % 8 == 0);
1769         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))
1770                 return false; /* read_callback_ sets the state for us */
1771
1772         if(!FLAC__bitreader_read_raw_uint64(decoder->private_->input, &obj->lead_in, FLAC__STREAM_METADATA_CUESHEET_LEAD_IN_LEN))
1773                 return false; /* read_callback_ sets the state for us */
1774
1775         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_IS_CD_LEN))
1776                 return false; /* read_callback_ sets the state for us */
1777         obj->is_cd = x? true : false;
1778
1779         if(!FLAC__bitreader_skip_bits_no_crc(decoder->private_->input, FLAC__STREAM_METADATA_CUESHEET_RESERVED_LEN))
1780                 return false; /* read_callback_ sets the state for us */
1781
1782         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_NUM_TRACKS_LEN))
1783                 return false; /* read_callback_ sets the state for us */
1784         obj->num_tracks = x;
1785
1786         if(obj->num_tracks > 0) {
1787                 if(0 == (obj->tracks = safe_calloc_(obj->num_tracks, sizeof(FLAC__StreamMetadata_CueSheet_Track)))) {
1788                         decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1789                         return false;
1790                 }
1791                 for(i = 0; i < obj->num_tracks; i++) {
1792                         FLAC__StreamMetadata_CueSheet_Track *track = &obj->tracks[i];
1793                         if(!FLAC__bitreader_read_raw_uint64(decoder->private_->input, &track->offset, FLAC__STREAM_METADATA_CUESHEET_TRACK_OFFSET_LEN))
1794                                 return false; /* read_callback_ sets the state for us */
1795
1796                         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_TRACK_NUMBER_LEN))
1797                                 return false; /* read_callback_ sets the state for us */
1798                         track->number = (FLAC__byte)x;
1799
1800                         FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_TRACK_ISRC_LEN % 8 == 0);
1801                         if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, (FLAC__byte*)track->isrc, FLAC__STREAM_METADATA_CUESHEET_TRACK_ISRC_LEN/8))
1802                                 return false; /* read_callback_ sets the state for us */
1803
1804                         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_TRACK_TYPE_LEN))
1805                                 return false; /* read_callback_ sets the state for us */
1806                         track->type = x;
1807
1808                         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_TRACK_PRE_EMPHASIS_LEN))
1809                                 return false; /* read_callback_ sets the state for us */
1810                         track->pre_emphasis = x;
1811
1812                         if(!FLAC__bitreader_skip_bits_no_crc(decoder->private_->input, FLAC__STREAM_METADATA_CUESHEET_TRACK_RESERVED_LEN))
1813                                 return false; /* read_callback_ sets the state for us */
1814
1815                         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_TRACK_NUM_INDICES_LEN))
1816                                 return false; /* read_callback_ sets the state for us */
1817                         track->num_indices = (FLAC__byte)x;
1818
1819                         if(track->num_indices > 0) {
1820                                 if(0 == (track->indices = safe_calloc_(track->num_indices, sizeof(FLAC__StreamMetadata_CueSheet_Index)))) {
1821                                         decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1822                                         return false;
1823                                 }
1824                                 for(j = 0; j < track->num_indices; j++) {
1825                                         FLAC__StreamMetadata_CueSheet_Index *index = &track->indices[j];
1826                                         if(!FLAC__bitreader_read_raw_uint64(decoder->private_->input, &index->offset, FLAC__STREAM_METADATA_CUESHEET_INDEX_OFFSET_LEN))
1827                                                 return false; /* read_callback_ sets the state for us */
1828
1829                                         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_INDEX_NUMBER_LEN))
1830                                                 return false; /* read_callback_ sets the state for us */
1831                                         index->number = (FLAC__byte)x;
1832
1833                                         if(!FLAC__bitreader_skip_bits_no_crc(decoder->private_->input, FLAC__STREAM_METADATA_CUESHEET_INDEX_RESERVED_LEN))
1834                                                 return false; /* read_callback_ sets the state for us */
1835                                 }
1836                         }
1837                 }
1838         }
1839
1840         return true;
1841 }
1842
1843 FLAC__bool read_metadata_picture_(FLAC__StreamDecoder *decoder, FLAC__StreamMetadata_Picture *obj)
1844 {
1845         FLAC__uint32 x;
1846
1847         FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));
1848
1849         /* read type */
1850         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_PICTURE_TYPE_LEN))
1851                 return false; /* read_callback_ sets the state for us */
1852         obj->type = x;
1853
1854         /* read MIME type */
1855         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_PICTURE_MIME_TYPE_LENGTH_LEN))
1856                 return false; /* read_callback_ sets the state for us */
1857         if(0 == (obj->mime_type = safe_malloc_add_2op_(x, /*+*/1))) {
1858                 decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1859                 return false;
1860         }
1861         if(x > 0) {
1862                 if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, (FLAC__byte*)obj->mime_type, x))
1863                         return false; /* read_callback_ sets the state for us */
1864         }
1865         obj->mime_type[x] = '\0';
1866
1867         /* read description */
1868         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_PICTURE_DESCRIPTION_LENGTH_LEN))
1869                 return false; /* read_callback_ sets the state for us */
1870         if(0 == (obj->description = safe_malloc_add_2op_(x, /*+*/1))) {
1871                 decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1872                 return false;
1873         }
1874         if(x > 0) {
1875                 if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, obj->description, x))
1876                         return false; /* read_callback_ sets the state for us */
1877         }
1878         obj->description[x] = '\0';
1879
1880         /* read width */
1881         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &obj->width, FLAC__STREAM_METADATA_PICTURE_WIDTH_LEN))
1882                 return false; /* read_callback_ sets the state for us */
1883
1884         /* read height */
1885         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &obj->height, FLAC__STREAM_METADATA_PICTURE_HEIGHT_LEN))
1886                 return false; /* read_callback_ sets the state for us */
1887
1888         /* read depth */
1889         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &obj->depth, FLAC__STREAM_METADATA_PICTURE_DEPTH_LEN))
1890                 return false; /* read_callback_ sets the state for us */
1891
1892         /* read colors */
1893         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &obj->colors, FLAC__STREAM_METADATA_PICTURE_COLORS_LEN))
1894                 return false; /* read_callback_ sets the state for us */
1895
1896         /* read data */
1897         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &(obj->data_length), FLAC__STREAM_METADATA_PICTURE_DATA_LENGTH_LEN))
1898                 return false; /* read_callback_ sets the state for us */
1899         if(0 == (obj->data = safe_malloc_(obj->data_length))) {
1900                 decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1901                 return false;
1902         }
1903         if(obj->data_length > 0) {
1904                 if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, obj->data, obj->data_length))
1905                         return false; /* read_callback_ sets the state for us */
1906         }
1907
1908         return true;
1909 }
1910
1911 FLAC__bool skip_id3v2_tag_(FLAC__StreamDecoder *decoder)
1912 {
1913         FLAC__uint32 x;
1914         unsigned i, skip;
1915
1916         /* skip the version and flags bytes */
1917         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 24))
1918                 return false; /* read_callback_ sets the state for us */
1919         /* get the size (in bytes) to skip */
1920         skip = 0;
1921         for(i = 0; i < 4; i++) {
1922                 if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
1923                         return false; /* read_callback_ sets the state for us */
1924                 skip <<= 7;
1925                 skip |= (x & 0x7f);
1926         }
1927         /* skip the rest of the tag */
1928         if(!FLAC__bitreader_skip_byte_block_aligned_no_crc(decoder->private_->input, skip))
1929                 return false; /* read_callback_ sets the state for us */
1930         return true;
1931 }
1932
1933 FLAC__bool frame_sync_(FLAC__StreamDecoder *decoder)
1934 {
1935         FLAC__uint32 x;
1936         FLAC__bool first = true;
1937
1938         /* If we know the total number of samples in the stream, stop if we've read that many. */
1939         /* This will stop us, for example, from wasting time trying to sync on an ID3V1 tag. */
1940         if(FLAC__stream_decoder_get_total_samples(decoder) > 0) {
1941                 if(decoder->private_->samples_decoded >= FLAC__stream_decoder_get_total_samples(decoder)) {
1942                         decoder->protected_->state = FLAC__STREAM_DECODER_END_OF_STREAM;
1943                         return true;
1944                 }
1945         }
1946
1947         /* make sure we're byte aligned */
1948         if(!FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input)) {
1949                 if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__bitreader_bits_left_for_byte_alignment(decoder->private_->input)))
1950                         return false; /* read_callback_ sets the state for us */
1951         }
1952
1953         while(1) {
1954                 if(decoder->private_->cached) {
1955                         x = (FLAC__uint32)decoder->private_->lookahead;
1956                         decoder->private_->cached = false;
1957                 }
1958                 else {
1959                         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
1960                                 return false; /* read_callback_ sets the state for us */
1961                 }
1962                 if(x == 0xff) { /* MAGIC NUMBER for the first 8 frame sync bits */
1963                         decoder->private_->header_warmup[0] = (FLAC__byte)x;
1964                         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
1965                                 return false; /* read_callback_ sets the state for us */
1966
1967                         /* 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 */
1968                         /* else we have to check if the second byte is the end of a sync code */
1969                         if(x == 0xff) { /* MAGIC NUMBER for the first 8 frame sync bits */
1970                                 decoder->private_->lookahead = (FLAC__byte)x;
1971                                 decoder->private_->cached = true;
1972                         }
1973                         else if(x >> 1 == 0x7c) { /* MAGIC NUMBER for the last 6 sync bits and reserved 7th bit */
1974                                 decoder->private_->header_warmup[1] = (FLAC__byte)x;
1975                                 decoder->protected_->state = FLAC__STREAM_DECODER_READ_FRAME;
1976                                 return true;
1977                         }
1978                 }
1979                 if(first) {
1980                         send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
1981                         first = false;
1982                 }
1983         }
1984
1985         return true;
1986 }
1987
1988 FLAC__bool read_frame_(FLAC__StreamDecoder *decoder, FLAC__bool *got_a_frame, FLAC__bool do_full_decode)
1989 {
1990         unsigned channel;
1991         unsigned i;
1992         FLAC__int32 mid, side;
1993         unsigned frame_crc; /* the one we calculate from the input stream */
1994         FLAC__uint32 x;
1995
1996         *got_a_frame = false;
1997
1998         /* init the CRC */
1999         frame_crc = 0;
2000         frame_crc = FLAC__CRC16_UPDATE(decoder->private_->header_warmup[0], frame_crc);
2001         frame_crc = FLAC__CRC16_UPDATE(decoder->private_->header_warmup[1], frame_crc);
2002         FLAC__bitreader_reset_read_crc16(decoder->private_->input, (FLAC__uint16)frame_crc);
2003
2004         if(!read_frame_header_(decoder))
2005                 return false;
2006         if(decoder->protected_->state == FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC) /* means we didn't sync on a valid header */
2007                 return true;
2008         if(!allocate_output_(decoder, decoder->private_->frame.header.blocksize, decoder->private_->frame.header.channels))
2009                 return false;
2010         for(channel = 0; channel < decoder->private_->frame.header.channels; channel++) {
2011                 /*
2012                  * first figure the correct bits-per-sample of the subframe
2013                  */
2014                 unsigned bps = decoder->private_->frame.header.bits_per_sample;
2015                 switch(decoder->private_->frame.header.channel_assignment) {
2016                         case FLAC__CHANNEL_ASSIGNMENT_INDEPENDENT:
2017                                 /* no adjustment needed */
2018                                 break;
2019                         case FLAC__CHANNEL_ASSIGNMENT_LEFT_SIDE:
2020                                 FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
2021                                 if(channel == 1)
2022                                         bps++;
2023                                 break;
2024                         case FLAC__CHANNEL_ASSIGNMENT_RIGHT_SIDE:
2025                                 FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
2026                                 if(channel == 0)
2027                                         bps++;
2028                                 break;
2029                         case FLAC__CHANNEL_ASSIGNMENT_MID_SIDE:
2030                                 FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
2031                                 if(channel == 1)
2032                                         bps++;
2033                                 break;
2034                         default:
2035                                 FLAC__ASSERT(0);
2036                 }
2037                 /*
2038                  * now read it
2039                  */
2040                 if(!read_subframe_(decoder, channel, bps, do_full_decode))
2041                         return false;
2042                 if(decoder->protected_->state == FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC) /* means bad sync or got corruption */
2043                         return true;
2044         }
2045         if(!read_zero_padding_(decoder))
2046                 return false;
2047         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) */
2048                 return true;
2049
2050         /*
2051          * Read the frame CRC-16 from the footer and check
2052          */
2053         frame_crc = FLAC__bitreader_get_read_crc16(decoder->private_->input);
2054         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__FRAME_FOOTER_CRC_LEN))
2055                 return false; /* read_callback_ sets the state for us */
2056         if(frame_crc == x) {
2057                 if(do_full_decode) {
2058                         /* Undo any special channel coding */
2059                         switch(decoder->private_->frame.header.channel_assignment) {
2060                                 case FLAC__CHANNEL_ASSIGNMENT_INDEPENDENT:
2061                                         /* do nothing */
2062                                         break;
2063                                 case FLAC__CHANNEL_ASSIGNMENT_LEFT_SIDE:
2064                                         FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
2065                                         for(i = 0; i < decoder->private_->frame.header.blocksize; i++)
2066                                                 decoder->private_->output[1][i] = decoder->private_->output[0][i] - decoder->private_->output[1][i];
2067                                         break;
2068                                 case FLAC__CHANNEL_ASSIGNMENT_RIGHT_SIDE:
2069                                         FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
2070                                         for(i = 0; i < decoder->private_->frame.header.blocksize; i++)
2071                                                 decoder->private_->output[0][i] += decoder->private_->output[1][i];
2072                                         break;
2073                                 case FLAC__CHANNEL_ASSIGNMENT_MID_SIDE:
2074                                         FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
2075                                         for(i = 0; i < decoder->private_->frame.header.blocksize; i++) {
2076 #if 1
2077                                                 mid = decoder->private_->output[0][i];
2078                                                 side = decoder->private_->output[1][i];
2079                                                 mid <<= 1;
2080                                                 mid |= (side & 1); /* i.e. if 'side' is odd... */
2081                                                 decoder->private_->output[0][i] = (mid + side) >> 1;
2082                                                 decoder->private_->output[1][i] = (mid - side) >> 1;
2083 #else
2084                                                 /* OPT: without 'side' temp variable */
2085                                                 mid = (decoder->private_->output[0][i] << 1) | (decoder->private_->output[1][i] & 1); /* i.e. if 'side' is odd... */
2086                                                 decoder->private_->output[0][i] = (mid + decoder->private_->output[1][i]) >> 1;
2087                                                 decoder->private_->output[1][i] = (mid - decoder->private_->output[1][i]) >> 1;
2088 #endif
2089                                         }
2090                                         break;
2091                                 default:
2092                                         FLAC__ASSERT(0);
2093                                         break;
2094                         }
2095                 }
2096         }
2097         else {
2098                 /* Bad frame, emit error and zero the output signal */
2099                 send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_FRAME_CRC_MISMATCH);
2100                 if(do_full_decode) {
2101                         for(channel = 0; channel < decoder->private_->frame.header.channels; channel++) {
2102                                 memset(decoder->private_->output[channel], 0, sizeof(FLAC__int32) * decoder->private_->frame.header.blocksize);
2103                         }
2104                 }
2105         }
2106
2107         *got_a_frame = true;
2108
2109         /* we wait to update fixed_block_size until here, when we're sure we've got a proper frame and hence a correct blocksize */
2110         if(decoder->private_->next_fixed_block_size)
2111                 decoder->private_->fixed_block_size = decoder->private_->next_fixed_block_size;
2112
2113         /* put the latest values into the public section of the decoder instance */
2114         decoder->protected_->channels = decoder->private_->frame.header.channels;
2115         decoder->protected_->channel_assignment = decoder->private_->frame.header.channel_assignment;
2116         decoder->protected_->bits_per_sample = decoder->private_->frame.header.bits_per_sample;
2117         decoder->protected_->sample_rate = decoder->private_->frame.header.sample_rate;
2118         decoder->protected_->blocksize = decoder->private_->frame.header.blocksize;
2119
2120         FLAC__ASSERT(decoder->private_->frame.header.number_type == FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER);
2121         decoder->private_->samples_decoded = decoder->private_->frame.header.number.sample_number + decoder->private_->frame.header.blocksize;
2122
2123         /* write it */
2124         if(do_full_decode) {
2125                 if(write_audio_frame_to_client_(decoder, &decoder->private_->frame, (const FLAC__int32 * const *)decoder->private_->output) != FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE)
2126                         return false;
2127         }
2128
2129         decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2130         return true;
2131 }
2132
2133 FLAC__bool read_frame_header_(FLAC__StreamDecoder *decoder)
2134 {
2135         FLAC__uint32 x;
2136         FLAC__uint64 xx;
2137         unsigned i, blocksize_hint = 0, sample_rate_hint = 0;
2138         FLAC__byte crc8, raw_header[16]; /* MAGIC NUMBER based on the maximum frame header size, including CRC */
2139         unsigned raw_header_len;
2140         FLAC__bool is_unparseable = false;
2141
2142         FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));
2143
2144         /* init the raw header with the saved bits from synchronization */
2145         raw_header[0] = decoder->private_->header_warmup[0];
2146         raw_header[1] = decoder->private_->header_warmup[1];
2147         raw_header_len = 2;
2148
2149         /* check to make sure that reserved bit is 0 */
2150         if(raw_header[1] & 0x02) /* MAGIC NUMBER */
2151                 is_unparseable = true;
2152
2153         /*
2154          * Note that along the way as we read the header, we look for a sync
2155          * code inside.  If we find one it would indicate that our original
2156          * sync was bad since there cannot be a sync code in a valid header.
2157          *
2158          * Three kinds of things can go wrong when reading the frame header:
2159          *  1) We may have sync'ed incorrectly and not landed on a frame header.
2160          *     If we don't find a sync code, it can end up looking like we read
2161          *     a valid but unparseable header, until getting to the frame header
2162          *     CRC.  Even then we could get a false positive on the CRC.
2163          *  2) We may have sync'ed correctly but on an unparseable frame (from a
2164          *     future encoder).
2165          *  3) We may be on a damaged frame which appears valid but unparseable.
2166          *
2167          * For all these reasons, we try and read a complete frame header as
2168          * long as it seems valid, even if unparseable, up until the frame
2169          * header CRC.
2170          */
2171
2172         /*
2173          * read in the raw header as bytes so we can CRC it, and parse it on the way
2174          */
2175         for(i = 0; i < 2; i++) {
2176                 if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
2177                         return false; /* read_callback_ sets the state for us */
2178                 if(x == 0xff) { /* MAGIC NUMBER for the first 8 frame sync bits */
2179                         /* if we get here it means our original sync was erroneous since the sync code cannot appear in the header */
2180                         decoder->private_->lookahead = (FLAC__byte)x;
2181                         decoder->private_->cached = true;
2182                         send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER);
2183                         decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2184                         return true;
2185                 }
2186                 raw_header[raw_header_len++] = (FLAC__byte)x;
2187         }
2188
2189         switch(x = raw_header[2] >> 4) {
2190                 case 0:
2191                         is_unparseable = true;
2192                         break;
2193                 case 1:
2194                         decoder->private_->frame.header.blocksize = 192;
2195                         break;
2196                 case 2:
2197                 case 3:
2198                 case 4:
2199                 case 5:
2200                         decoder->private_->frame.header.blocksize = 576 << (x-2);
2201                         break;
2202                 case 6:
2203                 case 7:
2204                         blocksize_hint = x;
2205                         break;
2206                 case 8:
2207                 case 9:
2208                 case 10:
2209                 case 11:
2210                 case 12:
2211                 case 13:
2212                 case 14:
2213                 case 15:
2214                         decoder->private_->frame.header.blocksize = 256 << (x-8);
2215                         break;
2216                 default:
2217                         FLAC__ASSERT(0);
2218                         break;
2219         }
2220
2221         switch(x = raw_header[2] & 0x0f) {
2222                 case 0:
2223                         if(decoder->private_->has_stream_info)
2224                                 decoder->private_->frame.header.sample_rate = decoder->private_->stream_info.data.stream_info.sample_rate;
2225                         else
2226                                 is_unparseable = true;
2227                         break;
2228                 case 1:
2229                         decoder->private_->frame.header.sample_rate = 88200;
2230                         break;
2231                 case 2:
2232                         decoder->private_->frame.header.sample_rate = 176400;
2233                         break;
2234                 case 3:
2235                         decoder->private_->frame.header.sample_rate = 192000;
2236                         break;
2237                 case 4:
2238                         decoder->private_->frame.header.sample_rate = 8000;
2239                         break;
2240                 case 5:
2241                         decoder->private_->frame.header.sample_rate = 16000;
2242                         break;
2243                 case 6:
2244                         decoder->private_->frame.header.sample_rate = 22050;
2245                         break;
2246                 case 7:
2247                         decoder->private_->frame.header.sample_rate = 24000;
2248                         break;
2249                 case 8:
2250                         decoder->private_->frame.header.sample_rate = 32000;
2251                         break;
2252                 case 9:
2253                         decoder->private_->frame.header.sample_rate = 44100;
2254                         break;
2255                 case 10:
2256                         decoder->private_->frame.header.sample_rate = 48000;
2257                         break;
2258                 case 11:
2259                         decoder->private_->frame.header.sample_rate = 96000;
2260                         break;
2261                 case 12:
2262                 case 13:
2263                 case 14:
2264                         sample_rate_hint = x;
2265                         break;
2266                 case 15:
2267                         send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER);
2268                         decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2269                         return true;
2270                 default:
2271                         FLAC__ASSERT(0);
2272         }
2273
2274         x = (unsigned)(raw_header[3] >> 4);
2275         if(x & 8) {
2276                 decoder->private_->frame.header.channels = 2;
2277                 switch(x & 7) {
2278                         case 0:
2279                                 decoder->private_->frame.header.channel_assignment = FLAC__CHANNEL_ASSIGNMENT_LEFT_SIDE;
2280                                 break;
2281                         case 1:
2282                                 decoder->private_->frame.header.channel_assignment = FLAC__CHANNEL_ASSIGNMENT_RIGHT_SIDE;
2283                                 break;
2284                         case 2:
2285                                 decoder->private_->frame.header.channel_assignment = FLAC__CHANNEL_ASSIGNMENT_MID_SIDE;
2286                                 break;
2287                         default:
2288                                 is_unparseable = true;
2289                                 break;
2290                 }
2291         }
2292         else {
2293                 decoder->private_->frame.header.channels = (unsigned)x + 1;
2294                 decoder->private_->frame.header.channel_assignment = FLAC__CHANNEL_ASSIGNMENT_INDEPENDENT;
2295         }
2296
2297         switch(x = (unsigned)(raw_header[3] & 0x0e) >> 1) {
2298                 case 0:
2299                         if(decoder->private_->has_stream_info)
2300                                 decoder->private_->frame.header.bits_per_sample = decoder->private_->stream_info.data.stream_info.bits_per_sample;
2301                         else
2302                                 is_unparseable = true;
2303                         break;
2304                 case 1:
2305                         decoder->private_->frame.header.bits_per_sample = 8;
2306                         break;
2307                 case 2:
2308                         decoder->private_->frame.header.bits_per_sample = 12;
2309                         break;
2310                 case 4:
2311                         decoder->private_->frame.header.bits_per_sample = 16;
2312                         break;
2313                 case 5:
2314                         decoder->private_->frame.header.bits_per_sample = 20;
2315                         break;
2316                 case 6:
2317                         decoder->private_->frame.header.bits_per_sample = 24;
2318                         break;
2319                 case 3:
2320                 case 7:
2321                         is_unparseable = true;
2322                         break;
2323                 default:
2324                         FLAC__ASSERT(0);
2325                         break;
2326         }
2327
2328         /* check to make sure that reserved bit is 0 */
2329         if(raw_header[3] & 0x01) /* MAGIC NUMBER */
2330                 is_unparseable = true;
2331
2332         /* read the frame's starting sample number (or frame number as the case may be) */
2333         if(
2334                 raw_header[1] & 0x01 ||
2335                 /*@@@ 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 */
2336                 (decoder->private_->has_stream_info && decoder->private_->stream_info.data.stream_info.min_blocksize != decoder->private_->stream_info.data.stream_info.max_blocksize)
2337         ) { /* variable blocksize */
2338                 if(!FLAC__bitreader_read_utf8_uint64(decoder->private_->input, &xx, raw_header, &raw_header_len))
2339                         return false; /* read_callback_ sets the state for us */
2340                 if(xx == FLAC__U64L(0xffffffffffffffff)) { /* i.e. non-UTF8 code... */
2341                         decoder->private_->lookahead = raw_header[raw_header_len-1]; /* back up as much as we can */
2342                         decoder->private_->cached = true;
2343                         send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER);
2344                         decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2345                         return true;
2346                 }
2347                 decoder->private_->frame.header.number_type = FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER;
2348                 decoder->private_->frame.header.number.sample_number = xx;
2349         }
2350         else { /* fixed blocksize */
2351                 if(!FLAC__bitreader_read_utf8_uint32(decoder->private_->input, &x, raw_header, &raw_header_len))
2352                         return false; /* read_callback_ sets the state for us */
2353                 if(x == 0xffffffff) { /* i.e. non-UTF8 code... */
2354                         decoder->private_->lookahead = raw_header[raw_header_len-1]; /* back up as much as we can */
2355                         decoder->private_->cached = true;
2356                         send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER);
2357                         decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2358                         return true;
2359                 }
2360                 decoder->private_->frame.header.number_type = FLAC__FRAME_NUMBER_TYPE_FRAME_NUMBER;
2361                 decoder->private_->frame.header.number.frame_number = x;
2362         }
2363
2364         if(blocksize_hint) {
2365                 if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
2366                         return false; /* read_callback_ sets the state for us */
2367                 raw_header[raw_header_len++] = (FLAC__byte)x;
2368                 if(blocksize_hint == 7) {
2369                         FLAC__uint32 _x;
2370                         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &_x, 8))
2371                                 return false; /* read_callback_ sets the state for us */
2372                         raw_header[raw_header_len++] = (FLAC__byte)_x;
2373                         x = (x << 8) | _x;
2374                 }
2375                 decoder->private_->frame.header.blocksize = x+1;
2376         }
2377
2378         if(sample_rate_hint) {
2379                 if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
2380                         return false; /* read_callback_ sets the state for us */
2381                 raw_header[raw_header_len++] = (FLAC__byte)x;
2382                 if(sample_rate_hint != 12) {
2383                         FLAC__uint32 _x;
2384                         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &_x, 8))
2385                                 return false; /* read_callback_ sets the state for us */
2386                         raw_header[raw_header_len++] = (FLAC__byte)_x;
2387                         x = (x << 8) | _x;
2388                 }
2389                 if(sample_rate_hint == 12)
2390                         decoder->private_->frame.header.sample_rate = x*1000;
2391                 else if(sample_rate_hint == 13)
2392                         decoder->private_->frame.header.sample_rate = x;
2393                 else
2394                         decoder->private_->frame.header.sample_rate = x*10;
2395         }
2396
2397         /* read the CRC-8 byte */
2398         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
2399                 return false; /* read_callback_ sets the state for us */
2400         crc8 = (FLAC__byte)x;
2401
2402         if(FLAC__crc8(raw_header, raw_header_len) != crc8) {
2403                 send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER);
2404                 decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2405                 return true;
2406         }
2407
2408         /* calculate the sample number from the frame number if needed */
2409         decoder->private_->next_fixed_block_size = 0;
2410         if(decoder->private_->frame.header.number_type == FLAC__FRAME_NUMBER_TYPE_FRAME_NUMBER) {
2411                 x = decoder->private_->frame.header.number.frame_number;
2412                 decoder->private_->frame.header.number_type = FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER;
2413                 if(decoder->private_->fixed_block_size)
2414                         decoder->private_->frame.header.number.sample_number = (FLAC__uint64)decoder->private_->fixed_block_size * (FLAC__uint64)x;
2415                 else if(decoder->private_->has_stream_info) {
2416                         if(decoder->private_->stream_info.data.stream_info.min_blocksize == decoder->private_->stream_info.data.stream_info.max_blocksize) {
2417                                 decoder->private_->frame.header.number.sample_number = (FLAC__uint64)decoder->private_->stream_info.data.stream_info.min_blocksize * (FLAC__uint64)x;
2418                                 decoder->private_->next_fixed_block_size = decoder->private_->stream_info.data.stream_info.max_blocksize;
2419                         }
2420                         else
2421                                 is_unparseable = true;
2422                 }
2423                 else if(x == 0) {
2424                         decoder->private_->frame.header.number.sample_number = 0;
2425                         decoder->private_->next_fixed_block_size = decoder->private_->frame.header.blocksize;
2426                 }
2427                 else {
2428                         /* can only get here if the stream has invalid frame numbering and no STREAMINFO, so assume it's not the last (possibly short) frame */
2429                         decoder->private_->frame.header.number.sample_number = (FLAC__uint64)decoder->private_->frame.header.blocksize * (FLAC__uint64)x;
2430                 }
2431         }
2432
2433         if(is_unparseable) {
2434                 send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM);
2435                 decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2436                 return true;
2437         }
2438
2439         return true;
2440 }
2441
2442 FLAC__bool read_subframe_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, FLAC__bool do_full_decode)
2443 {
2444         FLAC__uint32 x;
2445         FLAC__bool wasted_bits;
2446         unsigned i;
2447
2448         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8)) /* MAGIC NUMBER */
2449                 return false; /* read_callback_ sets the state for us */
2450
2451         wasted_bits = (x & 1);
2452         x &= 0xfe;
2453
2454         if(wasted_bits) {
2455                 unsigned u;
2456                 if(!FLAC__bitreader_read_unary_unsigned(decoder->private_->input, &u))
2457                         return false; /* read_callback_ sets the state for us */
2458                 decoder->private_->frame.subframes[channel].wasted_bits = u+1;
2459                 bps -= decoder->private_->frame.subframes[channel].wasted_bits;
2460         }
2461         else
2462                 decoder->private_->frame.subframes[channel].wasted_bits = 0;
2463
2464         /*
2465          * Lots of magic numbers here
2466          */
2467         if(x & 0x80) {
2468                 send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
2469                 decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2470                 return true;
2471         }
2472         else if(x == 0) {
2473                 if(!read_subframe_constant_(decoder, channel, bps, do_full_decode))
2474                         return false;
2475         }
2476         else if(x == 2) {
2477                 if(!read_subframe_verbatim_(decoder, channel, bps, do_full_decode))
2478                         return false;
2479         }
2480         else if(x < 16) {
2481                 send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM);
2482                 decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2483                 return true;
2484         }
2485         else if(x <= 24) {
2486                 if(!read_subframe_fixed_(decoder, channel, bps, (x>>1)&7, do_full_decode))
2487                         return false;
2488                 if(decoder->protected_->state == FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC) /* means bad sync or got corruption */
2489                         return true;
2490         }
2491         else if(x < 64) {
2492                 send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM);
2493                 decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2494                 return true;
2495         }
2496         else {
2497                 if(!read_subframe_lpc_(decoder, channel, bps, ((x>>1)&31)+1, do_full_decode))
2498                         return false;
2499                 if(decoder->protected_->state == FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC) /* means bad sync or got corruption */
2500                         return true;
2501         }
2502
2503         if(wasted_bits && do_full_decode) {
2504                 x = decoder->private_->frame.subframes[channel].wasted_bits;
2505                 for(i = 0; i < decoder->private_->frame.header.blocksize; i++)
2506                         decoder->private_->output[channel][i] <<= x;
2507         }
2508
2509         return true;
2510 }
2511
2512 FLAC__bool read_subframe_constant_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, FLAC__bool do_full_decode)
2513 {
2514         FLAC__Subframe_Constant *subframe = &decoder->private_->frame.subframes[channel].data.constant;
2515         FLAC__int32 x;
2516         unsigned i;
2517         FLAC__int32 *output = decoder->private_->output[channel];
2518
2519         decoder->private_->frame.subframes[channel].type = FLAC__SUBFRAME_TYPE_CONSTANT;
2520
2521         if(!FLAC__bitreader_read_raw_int32(decoder->private_->input, &x, bps))
2522                 return false; /* read_callback_ sets the state for us */
2523
2524         subframe->value = x;
2525
2526         /* decode the subframe */
2527         if(do_full_decode) {
2528                 for(i = 0; i < decoder->private_->frame.header.blocksize; i++)
2529                         output[i] = x;
2530         }
2531
2532         return true;
2533 }
2534
2535 FLAC__bool read_subframe_fixed_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, const unsigned order, FLAC__bool do_full_decode)
2536 {
2537         FLAC__Subframe_Fixed *subframe = &decoder->private_->frame.subframes[channel].data.fixed;
2538         FLAC__int32 i32;
2539         FLAC__uint32 u32;
2540         unsigned u;
2541
2542         decoder->private_->frame.subframes[channel].type = FLAC__SUBFRAME_TYPE_FIXED;
2543
2544         subframe->residual = decoder->private_->residual[channel];
2545         subframe->order = order;
2546
2547         /* read warm-up samples */
2548         for(u = 0; u < order; u++) {
2549                 if(!FLAC__bitreader_read_raw_int32(decoder->private_->input, &i32, bps))
2550                         return false; /* read_callback_ sets the state for us */
2551                 subframe->warmup[u] = i32;
2552         }
2553
2554         /* read entropy coding method info */
2555         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &u32, FLAC__ENTROPY_CODING_METHOD_TYPE_LEN))
2556                 return false; /* read_callback_ sets the state for us */
2557         subframe->entropy_coding_method.type = (FLAC__EntropyCodingMethodType)u32;
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(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &u32, FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_ORDER_LEN))
2562                                 return false; /* read_callback_ sets the state for us */
2563                         subframe->entropy_coding_method.data.partitioned_rice.order = u32;
2564                         subframe->entropy_coding_method.data.partitioned_rice.contents = &decoder->private_->partitioned_rice_contents[channel];
2565                         break;
2566                 default:
2567                         send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM);
2568                         decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2569                         return true;
2570         }
2571
2572         /* read residual */
2573         switch(subframe->entropy_coding_method.type) {
2574                 case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE:
2575                 case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2:
2576                         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))
2577                                 return false;
2578                         break;
2579                 default:
2580                         FLAC__ASSERT(0);
2581         }
2582
2583         /* decode the subframe */
2584         if(do_full_decode) {
2585                 memcpy(decoder->private_->output[channel], subframe->warmup, sizeof(FLAC__int32) * order);
2586                 FLAC__fixed_restore_signal(decoder->private_->residual[channel], decoder->private_->frame.header.blocksize-order, order, decoder->private_->output[channel]+order);
2587         }
2588
2589         return true;
2590 }
2591
2592 FLAC__bool read_subframe_lpc_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, const unsigned order, FLAC__bool do_full_decode)
2593 {
2594         FLAC__Subframe_LPC *subframe = &decoder->private_->frame.subframes[channel].data.lpc;
2595         FLAC__int32 i32;
2596         FLAC__uint32 u32;
2597         unsigned u;
2598
2599         decoder->private_->frame.subframes[channel].type = FLAC__SUBFRAME_TYPE_LPC;
2600
2601         subframe->residual = decoder->private_->residual[channel];
2602         subframe->order = order;
2603
2604         /* read warm-up samples */
2605         for(u = 0; u < order; u++) {
2606                 if(!FLAC__bitreader_read_raw_int32(decoder->private_->input, &i32, bps))
2607                         return false; /* read_callback_ sets the state for us */
2608                 subframe->warmup[u] = i32;
2609         }
2610
2611         /* read qlp coeff precision */
2612         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &u32, FLAC__SUBFRAME_LPC_QLP_COEFF_PRECISION_LEN))
2613                 return false; /* read_callback_ sets the state for us */
2614         if(u32 == (1u << FLAC__SUBFRAME_LPC_QLP_COEFF_PRECISION_LEN) - 1) {
2615                 send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
2616                 decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2617                 return true;
2618         }
2619         subframe->qlp_coeff_precision = u32+1;
2620
2621         /* read qlp shift */
2622         if(!FLAC__bitreader_read_raw_int32(decoder->private_->input, &i32, FLAC__SUBFRAME_LPC_QLP_SHIFT_LEN))
2623                 return false; /* read_callback_ sets the state for us */
2624         subframe->quantization_level = i32;
2625
2626         /* read quantized lp coefficiencts */
2627         for(u = 0; u < order; u++) {
2628                 if(!FLAC__bitreader_read_raw_int32(decoder->private_->input, &i32, subframe->qlp_coeff_precision))
2629                         return false; /* read_callback_ sets the state for us */
2630                 subframe->qlp_coeff[u] = i32;
2631         }
2632
2633         /* read entropy coding method info */
2634         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &u32, FLAC__ENTROPY_CODING_METHOD_TYPE_LEN))
2635                 return false; /* read_callback_ sets the state for us */
2636         subframe->entropy_coding_method.type = (FLAC__EntropyCodingMethodType)u32;
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(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &u32, FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_ORDER_LEN))
2641                                 return false; /* read_callback_ sets the state for us */
2642                         subframe->entropy_coding_method.data.partitioned_rice.order = u32;
2643                         subframe->entropy_coding_method.data.partitioned_rice.contents = &decoder->private_->partitioned_rice_contents[channel];
2644                         break;
2645                 default:
2646                         send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM);
2647                         decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2648                         return true;
2649         }
2650
2651         /* read residual */
2652         switch(subframe->entropy_coding_method.type) {
2653                 case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE:
2654                 case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2:
2655                         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))
2656                                 return false;
2657                         break;
2658                 default:
2659                         FLAC__ASSERT(0);
2660         }
2661
2662         /* decode the subframe */
2663         if(do_full_decode) {
2664                 memcpy(decoder->private_->output[channel], subframe->warmup, sizeof(FLAC__int32) * order);
2665                 /*@@@@@@ technically not pessimistic enough, should be more like
2666                 if( (FLAC__uint64)order * ((((FLAC__uint64)1)<<bps)-1) * ((1<<subframe->qlp_coeff_precision)-1) < (((FLAC__uint64)-1) << 32) )
2667                 */
2668                 if(bps + subframe->qlp_coeff_precision + FLAC__bitmath_ilog2(order) <= 32)
2669                         if(bps <= 16 && subframe->qlp_coeff_precision <= 16) {
2670                                 if(order <= 8)
2671                                         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);
2672                                 else
2673                                         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);
2674                         }
2675                         else
2676                                 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);
2677                 else
2678                         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);
2679         }
2680
2681         return true;
2682 }
2683
2684 FLAC__bool read_subframe_verbatim_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, FLAC__bool do_full_decode)
2685 {
2686         FLAC__Subframe_Verbatim *subframe = &decoder->private_->frame.subframes[channel].data.verbatim;
2687         FLAC__int32 x, *residual = decoder->private_->residual[channel];
2688         unsigned i;
2689
2690         decoder->private_->frame.subframes[channel].type = FLAC__SUBFRAME_TYPE_VERBATIM;
2691
2692         subframe->data = residual;
2693
2694         for(i = 0; i < decoder->private_->frame.header.blocksize; i++) {
2695                 if(!FLAC__bitreader_read_raw_int32(decoder->private_->input, &x, bps))
2696                         return false; /* read_callback_ sets the state for us */
2697                 residual[i] = x;
2698         }
2699
2700         /* decode the subframe */
2701         if(do_full_decode)
2702                 memcpy(decoder->private_->output[channel], subframe->data, sizeof(FLAC__int32) * decoder->private_->frame.header.blocksize);
2703
2704         return true;
2705 }
2706
2707 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)
2708 {
2709         FLAC__uint32 rice_parameter;
2710         int i;
2711         unsigned partition, sample, u;
2712         const unsigned partitions = 1u << partition_order;
2713         const unsigned partition_samples = partition_order > 0? decoder->private_->frame.header.blocksize >> partition_order : decoder->private_->frame.header.blocksize - predictor_order;
2714         const unsigned plen = is_extended? FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2_PARAMETER_LEN : FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_PARAMETER_LEN;
2715         const unsigned pesc = is_extended? FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2_ESCAPE_PARAMETER : FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_ESCAPE_PARAMETER;
2716
2717         /* sanity checks */
2718         if(partition_order == 0) {
2719                 if(decoder->private_->frame.header.blocksize < predictor_order) {
2720                         send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
2721                         decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2722                         return true;
2723                 }
2724         }
2725         else {
2726                 if(partition_samples < predictor_order) {
2727                         send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
2728                         decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2729                         return true;
2730                 }
2731         }
2732
2733         if(!FLAC__format_entropy_coding_method_partitioned_rice_contents_ensure_size(partitioned_rice_contents, flac_max(6u, partition_order))) {
2734                 decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
2735                 return false;
2736         }
2737
2738         sample = 0;
2739         for(partition = 0; partition < partitions; partition++) {
2740                 if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &rice_parameter, plen))
2741                         return false; /* read_callback_ sets the state for us */
2742                 partitioned_rice_contents->parameters[partition] = rice_parameter;
2743                 if(rice_parameter < pesc) {
2744                         partitioned_rice_contents->raw_bits[partition] = 0;
2745                         u = (partition_order == 0 || partition > 0)? partition_samples : partition_samples - predictor_order;
2746                         if(!decoder->private_->local_bitreader_read_rice_signed_block(decoder->private_->input, residual + sample, u, rice_parameter))
2747                                 return false; /* read_callback_ sets the state for us */
2748                         sample += u;
2749                 }
2750                 else {
2751                         if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &rice_parameter, FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_RAW_LEN))
2752                                 return false; /* read_callback_ sets the state for us */
2753                         partitioned_rice_contents->raw_bits[partition] = rice_parameter;
2754                         for(u = (partition_order == 0 || partition > 0)? 0 : predictor_order; u < partition_samples; u++, sample++) {
2755                                 if(!FLAC__bitreader_read_raw_int32(decoder->private_->input, &i, rice_parameter))
2756                                         return false; /* read_callback_ sets the state for us */
2757                                 residual[sample] = i;
2758                         }
2759                 }
2760         }
2761
2762         return true;
2763 }
2764
2765 FLAC__bool read_zero_padding_(FLAC__StreamDecoder *decoder)
2766 {
2767         if(!FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input)) {
2768                 FLAC__uint32 zero = 0;
2769                 if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &zero, FLAC__bitreader_bits_left_for_byte_alignment(decoder->private_->input)))
2770                         return false; /* read_callback_ sets the state for us */
2771                 if(zero != 0) {
2772                         send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
2773                         decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2774                 }
2775         }
2776         return true;
2777 }
2778
2779 FLAC__bool read_callback_(FLAC__byte buffer[], size_t *bytes, void *client_data)
2780 {
2781         FLAC__StreamDecoder *decoder = (FLAC__StreamDecoder *)client_data;
2782
2783         if(
2784 #if FLAC__HAS_OGG
2785                 /* see [1] HACK NOTE below for why we don't call the eof_callback when decoding Ogg FLAC */
2786                 !decoder->private_->is_ogg &&
2787 #endif
2788                 decoder->private_->eof_callback && decoder->private_->eof_callback(decoder, decoder->private_->client_data)
2789         ) {
2790                 *bytes = 0;
2791                 decoder->protected_->state = FLAC__STREAM_DECODER_END_OF_STREAM;
2792                 return false;
2793         }
2794         else if(*bytes > 0) {
2795                 /* While seeking, it is possible for our seek to land in the
2796                  * middle of audio data that looks exactly like a frame header
2797                  * from a future version of an encoder.  When that happens, our
2798                  * error callback will get an
2799                  * FLAC__STREAM_DECODER_UNPARSEABLE_STREAM and increment its
2800                  * unparseable_frame_count.  But there is a remote possibility
2801                  * that it is properly synced at such a "future-codec frame",
2802                  * so to make sure, we wait to see many "unparseable" errors in
2803                  * a row before bailing out.
2804                  */
2805                 if(decoder->private_->is_seeking && decoder->private_->unparseable_frame_count > 20) {
2806                         decoder->protected_->state = FLAC__STREAM_DECODER_ABORTED;
2807                         return false;
2808                 }
2809                 else {
2810                         const FLAC__StreamDecoderReadStatus status =
2811 #if FLAC__HAS_OGG
2812                                 decoder->private_->is_ogg?
2813                                 read_callback_ogg_aspect_(decoder, buffer, bytes) :
2814 #endif
2815                                 decoder->private_->read_callback(decoder, buffer, bytes, decoder->private_->client_data)
2816                         ;
2817                         if(status == FLAC__STREAM_DECODER_READ_STATUS_ABORT) {
2818                                 decoder->protected_->state = FLAC__STREAM_DECODER_ABORTED;
2819                                 return false;
2820                         }
2821                         else if(*bytes == 0) {
2822                                 if(
2823                                         status == FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM ||
2824                                         (
2825 #if FLAC__HAS_OGG
2826                                                 /* see [1] HACK NOTE below for why we don't call the eof_callback when decoding Ogg FLAC */
2827                                                 !decoder->private_->is_ogg &&
2828 #endif
2829                                                 decoder->private_->eof_callback && decoder->private_->eof_callback(decoder, decoder->private_->client_data)
2830                                         )
2831                                 ) {
2832                                         decoder->protected_->state = FLAC__STREAM_DECODER_END_OF_STREAM;
2833                                         return false;
2834                                 }
2835                                 else
2836                                         return true;
2837                         }
2838                         else
2839                                 return true;
2840                 }
2841         }
2842         else {
2843                 /* abort to avoid a deadlock */
2844                 decoder->protected_->state = FLAC__STREAM_DECODER_ABORTED;
2845                 return false;
2846         }
2847         /* [1] @@@ HACK NOTE: The end-of-stream checking has to be hacked around
2848          * for Ogg FLAC.  This is because the ogg decoder aspect can lose sync
2849          * and at the same time hit the end of the stream (for example, seeking
2850          * to a point that is after the beginning of the last Ogg page).  There
2851          * is no way to report an Ogg sync loss through the callbacks (see note
2852          * in read_callback_ogg_aspect_()) so it returns CONTINUE with *bytes==0.
2853          * So to keep the decoder from stopping at this point we gate the call
2854          * to the eof_callback and let the Ogg decoder aspect set the
2855          * end-of-stream state when it is needed.
2856          */
2857 }
2858
2859 #if FLAC__HAS_OGG
2860 FLAC__StreamDecoderReadStatus read_callback_ogg_aspect_(const FLAC__StreamDecoder *decoder, FLAC__byte buffer[], size_t *bytes)
2861 {
2862         switch(FLAC__ogg_decoder_aspect_read_callback_wrapper(&decoder->protected_->ogg_decoder_aspect, buffer, bytes, read_callback_proxy_, decoder, decoder->private_->client_data)) {
2863                 case FLAC__OGG_DECODER_ASPECT_READ_STATUS_OK:
2864                         return FLAC__STREAM_DECODER_READ_STATUS_CONTINUE;
2865                 /* we don't really have a way to handle lost sync via read
2866                  * callback so we'll let it pass and let the underlying
2867                  * FLAC decoder catch the error
2868                  */
2869                 case FLAC__OGG_DECODER_ASPECT_READ_STATUS_LOST_SYNC:
2870                         return FLAC__STREAM_DECODER_READ_STATUS_CONTINUE;
2871                 case FLAC__OGG_DECODER_ASPECT_READ_STATUS_END_OF_STREAM:
2872                         return FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM;
2873                 case FLAC__OGG_DECODER_ASPECT_READ_STATUS_NOT_FLAC:
2874                 case FLAC__OGG_DECODER_ASPECT_READ_STATUS_UNSUPPORTED_MAPPING_VERSION:
2875                 case FLAC__OGG_DECODER_ASPECT_READ_STATUS_ABORT:
2876                 case FLAC__OGG_DECODER_ASPECT_READ_STATUS_ERROR:
2877                 case FLAC__OGG_DECODER_ASPECT_READ_STATUS_MEMORY_ALLOCATION_ERROR:
2878                         return FLAC__STREAM_DECODER_READ_STATUS_ABORT;
2879                 default:
2880                         FLAC__ASSERT(0);
2881                         /* double protection */
2882                         return FLAC__STREAM_DECODER_READ_STATUS_ABORT;
2883         }
2884 }
2885
2886 FLAC__OggDecoderAspectReadStatus read_callback_proxy_(const void *void_decoder, FLAC__byte buffer[], size_t *bytes, void *client_data)
2887 {
2888         FLAC__StreamDecoder *decoder = (FLAC__StreamDecoder*)void_decoder;
2889
2890         switch(decoder->private_->read_callback(decoder, buffer, bytes, client_data)) {
2891                 case FLAC__STREAM_DECODER_READ_STATUS_CONTINUE:
2892                         return FLAC__OGG_DECODER_ASPECT_READ_STATUS_OK;
2893                 case FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM:
2894                         return FLAC__OGG_DECODER_ASPECT_READ_STATUS_END_OF_STREAM;
2895                 case FLAC__STREAM_DECODER_READ_STATUS_ABORT:
2896                         return FLAC__OGG_DECODER_ASPECT_READ_STATUS_ABORT;
2897                 default:
2898                         /* double protection: */
2899                         FLAC__ASSERT(0);
2900                         return FLAC__OGG_DECODER_ASPECT_READ_STATUS_ABORT;
2901         }
2902 }
2903 #endif
2904
2905 FLAC__StreamDecoderWriteStatus write_audio_frame_to_client_(FLAC__StreamDecoder *decoder, const FLAC__Frame *frame, const FLAC__int32 * const buffer[])
2906 {
2907         if(decoder->private_->is_seeking) {
2908                 FLAC__uint64 this_frame_sample = frame->header.number.sample_number;
2909                 FLAC__uint64 next_frame_sample = this_frame_sample + (FLAC__uint64)frame->header.blocksize;
2910                 FLAC__uint64 target_sample = decoder->private_->target_sample;
2911
2912                 FLAC__ASSERT(frame->header.number_type == FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER);
2913
2914 #if FLAC__HAS_OGG
2915                 decoder->private_->got_a_frame = true;
2916 #endif
2917                 decoder->private_->last_frame = *frame; /* save the frame */
2918                 if(this_frame_sample <= target_sample && target_sample < next_frame_sample) { /* we hit our target frame */
2919                         unsigned delta = (unsigned)(target_sample - this_frame_sample);
2920                         /* kick out of seek mode */
2921                         decoder->private_->is_seeking = false;
2922                         /* shift out the samples before target_sample */
2923                         if(delta > 0) {
2924                                 unsigned channel;
2925                                 const FLAC__int32 *newbuffer[FLAC__MAX_CHANNELS];
2926                                 for(channel = 0; channel < frame->header.channels; channel++)
2927                                         newbuffer[channel] = buffer[channel] + delta;
2928                                 decoder->private_->last_frame.header.blocksize -= delta;
2929                                 decoder->private_->last_frame.header.number.sample_number += (FLAC__uint64)delta;
2930                                 /* write the relevant samples */
2931                                 return decoder->private_->write_callback(decoder, &decoder->private_->last_frame, newbuffer, decoder->private_->client_data);
2932                         }
2933                         else {
2934                                 /* write the relevant samples */
2935                                 return decoder->private_->write_callback(decoder, frame, buffer, decoder->private_->client_data);
2936                         }
2937                 }
2938                 else {
2939                         return FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE;
2940                 }
2941         }
2942         else {
2943                 /*
2944                  * If we never got STREAMINFO, turn off MD5 checking to save
2945                  * cycles since we don't have a sum to compare to anyway
2946                  */
2947                 if(!decoder->private_->has_stream_info)
2948                         decoder->private_->do_md5_checking = false;
2949                 if(decoder->private_->do_md5_checking) {
2950                         if(!FLAC__MD5Accumulate(&decoder->private_->md5context, buffer, frame->header.channels, frame->header.blocksize, (frame->header.bits_per_sample+7) / 8))
2951                                 return FLAC__STREAM_DECODER_WRITE_STATUS_ABORT;
2952                 }
2953                 return decoder->private_->write_callback(decoder, frame, buffer, decoder->private_->client_data);
2954         }
2955 }
2956
2957 void send_error_to_client_(const FLAC__StreamDecoder *decoder, FLAC__StreamDecoderErrorStatus status)
2958 {
2959         if(!decoder->private_->is_seeking)
2960                 decoder->private_->error_callback(decoder, status, decoder->private_->client_data);
2961         else if(status == FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM)
2962                 decoder->private_->unparseable_frame_count++;
2963 }
2964
2965 FLAC__bool seek_to_absolute_sample_(FLAC__StreamDecoder *decoder, FLAC__uint64 stream_length, FLAC__uint64 target_sample)
2966 {
2967         FLAC__uint64 first_frame_offset = decoder->private_->first_frame_offset, lower_bound, upper_bound, lower_bound_sample, upper_bound_sample, this_frame_sample;
2968         FLAC__int64 pos = -1;
2969         int i;
2970         unsigned approx_bytes_per_frame;
2971         FLAC__bool first_seek = true;
2972         const FLAC__uint64 total_samples = FLAC__stream_decoder_get_total_samples(decoder);
2973         const unsigned min_blocksize = decoder->private_->stream_info.data.stream_info.min_blocksize;
2974         const unsigned max_blocksize = decoder->private_->stream_info.data.stream_info.max_blocksize;
2975         const unsigned max_framesize = decoder->private_->stream_info.data.stream_info.max_framesize;
2976         const unsigned min_framesize = decoder->private_->stream_info.data.stream_info.min_framesize;
2977         /* take these from the current frame in case they've changed mid-stream */
2978         unsigned channels = FLAC__stream_decoder_get_channels(decoder);
2979         unsigned bps = FLAC__stream_decoder_get_bits_per_sample(decoder);
2980         const FLAC__StreamMetadata_SeekTable *seek_table = decoder->private_->has_seek_table? &decoder->private_->seek_table.data.seek_table : 0;
2981
2982         /* use values from stream info if we didn't decode a frame */
2983         if(channels == 0)
2984                 channels = decoder->private_->stream_info.data.stream_info.channels;
2985         if(bps == 0)
2986                 bps = decoder->private_->stream_info.data.stream_info.bits_per_sample;
2987
2988         /* we are just guessing here */
2989         if(max_framesize > 0)
2990                 approx_bytes_per_frame = (max_framesize + min_framesize) / 2 + 1;
2991         /*
2992          * Check if it's a known fixed-blocksize stream.  Note that though
2993          * the spec doesn't allow zeroes in the STREAMINFO block, we may
2994          * never get a STREAMINFO block when decoding so the value of
2995          * min_blocksize might be zero.
2996          */
2997         else if(min_blocksize == max_blocksize && min_blocksize > 0) {
2998                 /* note there are no () around 'bps/8' to keep precision up since it's an integer calulation */
2999                 approx_bytes_per_frame = min_blocksize * channels * bps/8 + 64;
3000         }
3001         else
3002                 approx_bytes_per_frame = 4096 * channels * bps/8 + 64;
3003
3004         /*
3005          * First, we set an upper and lower bound on where in the
3006          * stream we will search.  For now we assume the worst case
3007          * scenario, which is our best guess at the beginning of
3008          * the first frame and end of the stream.
3009          */
3010         lower_bound = first_frame_offset;
3011         lower_bound_sample = 0;
3012         upper_bound = stream_length;
3013         upper_bound_sample = total_samples > 0 ? total_samples : target_sample /*estimate it*/;
3014
3015         /*
3016          * Now we refine the bounds if we have a seektable with
3017          * suitable points.  Note that according to the spec they
3018          * must be ordered by ascending sample number.
3019          *
3020          * Note: to protect against invalid seek tables we will ignore points
3021          * that have frame_samples==0 or sample_number>=total_samples
3022          */
3023         if(seek_table) {
3024                 FLAC__uint64 new_lower_bound = lower_bound;
3025                 FLAC__uint64 new_upper_bound = upper_bound;
3026                 FLAC__uint64 new_lower_bound_sample = lower_bound_sample;
3027                 FLAC__uint64 new_upper_bound_sample = upper_bound_sample;
3028
3029                 /* find the closest seek point <= target_sample, if it exists */
3030                 for(i = (int)seek_table->num_points - 1; i >= 0; 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 >= 0) { /* i.e. we found a suitable seek point... */
3040                         new_lower_bound = first_frame_offset + seek_table->points[i].stream_offset;
3041                         new_lower_bound_sample = seek_table->points[i].sample_number;
3042                 }
3043
3044                 /* find the closest seek point > target_sample, if it exists */
3045                 for(i = 0; i < (int)seek_table->num_points; i++) {
3046                         if(
3047                                 seek_table->points[i].sample_number != FLAC__STREAM_METADATA_SEEKPOINT_PLACEHOLDER &&
3048                                 seek_table->points[i].frame_samples > 0 && /* defense against bad seekpoints */
3049                                 (total_samples <= 0 || seek_table->points[i].sample_number < total_samples) && /* defense against bad seekpoints */
3050                                 seek_table->points[i].sample_number > target_sample
3051                         )
3052                                 break;
3053                 }
3054                 if(i < (int)seek_table->num_points) { /* i.e. we found a suitable seek point... */
3055                         new_upper_bound = first_frame_offset + seek_table->points[i].stream_offset;
3056                         new_upper_bound_sample = seek_table->points[i].sample_number;
3057                 }
3058                 /* final protection against unsorted seek tables; keep original values if bogus */
3059                 if(new_upper_bound >= new_lower_bound) {
3060                         lower_bound = new_lower_bound;
3061                         upper_bound = new_upper_bound;
3062                         lower_bound_sample = new_lower_bound_sample;
3063                         upper_bound_sample = new_upper_bound_sample;
3064                 }
3065         }
3066
3067         FLAC__ASSERT(upper_bound_sample >= lower_bound_sample);
3068         /* there are 2 insidious ways that the following equality occurs, which
3069          * we need to fix:
3070          *  1) total_samples is 0 (unknown) and target_sample is 0
3071          *  2) total_samples is 0 (unknown) and target_sample happens to be
3072          *     exactly equal to the last seek point in the seek table; this
3073          *     means there is no seek point above it, and upper_bound_samples
3074          *     remains equal to the estimate (of target_samples) we made above
3075          * in either case it does not hurt to move upper_bound_sample up by 1
3076          */
3077         if(upper_bound_sample == lower_bound_sample)
3078                 upper_bound_sample++;
3079
3080         decoder->private_->target_sample = target_sample;
3081         while(1) {
3082                 /* check if the bounds are still ok */
3083                 if (lower_bound_sample >= upper_bound_sample || lower_bound > upper_bound) {
3084                         decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3085                         return false;
3086                 }
3087 #ifndef FLAC__INTEGER_ONLY_LIBRARY
3088 #if defined _MSC_VER || defined __MINGW32__
3089                 /* with VC++ you have to spoon feed it the casting */
3090                 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;
3091 #else
3092                 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;
3093 #endif
3094 #else
3095                 /* a little less accurate: */
3096                 if(upper_bound - lower_bound < 0xffffffff)
3097                         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;
3098                 else /* @@@ WATCHOUT, ~2TB limit */
3099                         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;
3100 #endif
3101                 if(pos >= (FLAC__int64)upper_bound)
3102                         pos = (FLAC__int64)upper_bound - 1;
3103                 if(pos < (FLAC__int64)lower_bound)
3104                         pos = (FLAC__int64)lower_bound;
3105                 if(decoder->private_->seek_callback(decoder, (FLAC__uint64)pos, decoder->private_->client_data) != FLAC__STREAM_DECODER_SEEK_STATUS_OK) {
3106                         decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3107                         return false;
3108                 }
3109                 if(!FLAC__stream_decoder_flush(decoder)) {
3110                         /* above call sets the state for us */
3111                         return false;
3112                 }
3113                 /* Now we need to get a frame.  First we need to reset our
3114                  * unparseable_frame_count; if we get too many unparseable
3115                  * frames in a row, the read callback will return
3116                  * FLAC__STREAM_DECODER_READ_STATUS_ABORT, causing
3117                  * FLAC__stream_decoder_process_single() to return false.
3118                  */
3119                 decoder->private_->unparseable_frame_count = 0;
3120                 if(!FLAC__stream_decoder_process_single(decoder)) {
3121                         decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3122                         return false;
3123                 }
3124                 /* our write callback will change the state when it gets to the target frame */
3125                 /* 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 */
3126 #if 0
3127                 /*@@@@@@ used to be the following; not clear if the check for end of stream is needed anymore */
3128                 if(decoder->protected_->state != FLAC__SEEKABLE_STREAM_DECODER_SEEKING && decoder->protected_->state != FLAC__STREAM_DECODER_END_OF_STREAM)
3129                         break;
3130 #endif
3131                 if(!decoder->private_->is_seeking)
3132                         break;
3133
3134                 FLAC__ASSERT(decoder->private_->last_frame.header.number_type == FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER);
3135                 this_frame_sample = decoder->private_->last_frame.header.number.sample_number;
3136
3137                 if (0 == decoder->private_->samples_decoded || (this_frame_sample + decoder->private_->last_frame.header.blocksize >= upper_bound_sample && !first_seek)) {
3138                         if (pos == (FLAC__int64)lower_bound) {
3139                                 /* can't move back any more than the first frame, something is fatally wrong */
3140                                 decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3141                                 return false;
3142                         }
3143                         /* our last move backwards wasn't big enough, try again */
3144                         approx_bytes_per_frame = approx_bytes_per_frame? approx_bytes_per_frame * 2 : 16;
3145                         continue;
3146                 }
3147                 /* allow one seek over upper bound, so we can get a correct upper_bound_sample for streams with unknown total_samples */
3148                 first_seek = false;
3149
3150                 /* make sure we are not seeking in corrupted stream */
3151                 if (this_frame_sample < lower_bound_sample) {
3152                         decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3153                         return false;
3154                 }
3155
3156                 /* we need to narrow the search */
3157                 if(target_sample < this_frame_sample) {
3158                         upper_bound_sample = this_frame_sample + decoder->private_->last_frame.header.blocksize;
3159 /*@@@@@@ what will decode position be if at end of stream? */
3160                         if(!FLAC__stream_decoder_get_decode_position(decoder, &upper_bound)) {
3161                                 decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3162                                 return false;
3163                         }
3164                         approx_bytes_per_frame = (unsigned)(2 * (upper_bound - pos) / 3 + 16);
3165                 }
3166                 else { /* target_sample >= this_frame_sample + this frame's blocksize */
3167                         lower_bound_sample = this_frame_sample + decoder->private_->last_frame.header.blocksize;
3168                         if(!FLAC__stream_decoder_get_decode_position(decoder, &lower_bound)) {
3169                                 decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3170                                 return false;
3171                         }
3172                         approx_bytes_per_frame = (unsigned)(2 * (lower_bound - pos) / 3 + 16);
3173                 }
3174         }
3175
3176         return true;
3177 }
3178
3179 #if FLAC__HAS_OGG
3180 FLAC__bool seek_to_absolute_sample_ogg_(FLAC__StreamDecoder *decoder, FLAC__uint64 stream_length, FLAC__uint64 target_sample)
3181 {
3182         FLAC__uint64 left_pos = 0, right_pos = stream_length;
3183         FLAC__uint64 left_sample = 0, right_sample = FLAC__stream_decoder_get_total_samples(decoder);
3184         FLAC__uint64 this_frame_sample = (FLAC__uint64)0 - 1;
3185         FLAC__uint64 pos = 0; /* only initialized to avoid compiler warning */
3186         FLAC__bool did_a_seek;
3187         unsigned iteration = 0;
3188
3189         /* In the first iterations, we will calculate the target byte position
3190          * by the distance from the target sample to left_sample and
3191          * right_sample (let's call it "proportional search").  After that, we
3192          * will switch to binary search.
3193          */
3194         unsigned BINARY_SEARCH_AFTER_ITERATION = 2;
3195
3196         /* We will switch to a linear search once our current sample is less
3197          * than this number of samples ahead of the target sample
3198          */
3199         static const FLAC__uint64 LINEAR_SEARCH_WITHIN_SAMPLES = FLAC__MAX_BLOCK_SIZE * 2;
3200
3201         /* If the total number of samples is unknown, use a large value, and
3202          * force binary search immediately.
3203          */
3204         if(right_sample == 0) {
3205                 right_sample = (FLAC__uint64)(-1);
3206                 BINARY_SEARCH_AFTER_ITERATION = 0;
3207         }
3208
3209         decoder->private_->target_sample = target_sample;
3210         for( ; ; iteration++) {
3211                 if (iteration == 0 || this_frame_sample > target_sample || target_sample - this_frame_sample > LINEAR_SEARCH_WITHIN_SAMPLES) {
3212                         if (iteration >= BINARY_SEARCH_AFTER_ITERATION) {
3213                                 pos = (right_pos + left_pos) / 2;
3214                         }
3215                         else {
3216 #ifndef FLAC__INTEGER_ONLY_LIBRARY
3217 #if defined _MSC_VER || defined __MINGW32__
3218                                 /* with MSVC you have to spoon feed it the casting */
3219                                 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));
3220 #else
3221                                 pos = (FLAC__uint64)((FLAC__double)(target_sample - left_sample) / (FLAC__double)(right_sample - left_sample) * (FLAC__double)(right_pos - left_pos));
3222 #endif
3223 #else
3224                                 /* a little less accurate: */
3225                                 if ((target_sample-left_sample <= 0xffffffff) && (right_pos-left_pos <= 0xffffffff))
3226                                         pos = (FLAC__int64)(((target_sample-left_sample) * (right_pos-left_pos)) / (right_sample-left_sample));
3227                                 else /* @@@ WATCHOUT, ~2TB limit */
3228                                         pos = (FLAC__int64)((((target_sample-left_sample)>>8) * ((right_pos-left_pos)>>8)) / ((right_sample-left_sample)>>16));
3229 #endif
3230                                 /* @@@ TODO: might want to limit pos to some distance
3231                                  * before EOF, to make sure we land before the last frame,
3232                                  * thereby getting a this_frame_sample and so having a better
3233                                  * estimate.
3234                                  */
3235                         }
3236
3237                         /* physical seek */
3238                         if(decoder->private_->seek_callback((FLAC__StreamDecoder*)decoder, (FLAC__uint64)pos, decoder->private_->client_data) != FLAC__STREAM_DECODER_SEEK_STATUS_OK) {
3239                                 decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3240                                 return false;
3241                         }
3242                         if(!FLAC__stream_decoder_flush(decoder)) {
3243                                 /* above call sets the state for us */
3244                                 return false;
3245                         }
3246                         did_a_seek = true;
3247                 }
3248                 else
3249                         did_a_seek = false;
3250
3251                 decoder->private_->got_a_frame = false;
3252                 if(!FLAC__stream_decoder_process_single(decoder)) {
3253                         decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3254                         return false;
3255                 }
3256                 if(!decoder->private_->got_a_frame) {
3257                         if(did_a_seek) {
3258                                 /* this can happen if we seek to a point after the last frame; we drop
3259                                  * to binary search right away in this case to avoid any wasted
3260                                  * iterations of proportional search.
3261                                  */
3262                                 right_pos = pos;
3263                                 BINARY_SEARCH_AFTER_ITERATION = 0;
3264                         }
3265                         else {
3266                                 /* this can probably only happen if total_samples is unknown and the
3267                                  * target_sample is past the end of the stream
3268                                  */
3269                                 decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3270                                 return false;
3271                         }
3272                 }
3273                 /* our write callback will change the state when it gets to the target frame */
3274                 else if(!decoder->private_->is_seeking) {
3275                         break;
3276                 }
3277                 else {
3278                         this_frame_sample = decoder->private_->last_frame.header.number.sample_number;
3279                         FLAC__ASSERT(decoder->private_->last_frame.header.number_type == FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER);
3280
3281                         if (did_a_seek) {
3282                                 if (this_frame_sample <= target_sample) {
3283                                         /* The 'equal' case should not happen, since
3284                                          * FLAC__stream_decoder_process_single()
3285                                          * should recognize that it has hit the
3286                                          * target sample and we would exit through
3287                                          * the 'break' above.
3288                                          */
3289                                         FLAC__ASSERT(this_frame_sample != target_sample);
3290
3291                                         left_sample = this_frame_sample;
3292                                         /* sanity check to avoid infinite loop */
3293                                         if (left_pos == pos) {
3294                                                 decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3295                                                 return false;
3296                                         }
3297                                         left_pos = pos;
3298                                 }
3299                                 else if(this_frame_sample > target_sample) {
3300                                         right_sample = this_frame_sample;
3301                                         /* sanity check to avoid infinite loop */
3302                                         if (right_pos == pos) {
3303                                                 decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3304                                                 return false;
3305                                         }
3306                                         right_pos = pos;
3307                                 }
3308                         }
3309                 }
3310         }
3311
3312         return true;
3313 }
3314 #endif
3315
3316 FLAC__StreamDecoderReadStatus file_read_callback_(const FLAC__StreamDecoder *decoder, FLAC__byte buffer[], size_t *bytes, void *client_data)
3317 {
3318         (void)client_data;
3319
3320         if(*bytes > 0) {
3321                 *bytes = fread(buffer, sizeof(FLAC__byte), *bytes, decoder->private_->file);
3322                 if(ferror(decoder->private_->file))
3323                         return FLAC__STREAM_DECODER_READ_STATUS_ABORT;
3324                 else if(*bytes == 0)
3325                         return FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM;
3326                 else
3327                         return FLAC__STREAM_DECODER_READ_STATUS_CONTINUE;
3328         }
3329         else
3330                 return FLAC__STREAM_DECODER_READ_STATUS_ABORT; /* abort to avoid a deadlock */
3331 }
3332
3333 FLAC__StreamDecoderSeekStatus file_seek_callback_(const FLAC__StreamDecoder *decoder, FLAC__uint64 absolute_byte_offset, void *client_data)
3334 {
3335         (void)client_data;
3336
3337         if(decoder->private_->file == stdin)
3338                 return FLAC__STREAM_DECODER_SEEK_STATUS_UNSUPPORTED;
3339         else if(fseeko(decoder->private_->file, (off_t)absolute_byte_offset, SEEK_SET) < 0)
3340                 return FLAC__STREAM_DECODER_SEEK_STATUS_ERROR;
3341         else
3342                 return FLAC__STREAM_DECODER_SEEK_STATUS_OK;
3343 }
3344
3345 FLAC__StreamDecoderTellStatus file_tell_callback_(const FLAC__StreamDecoder *decoder, FLAC__uint64 *absolute_byte_offset, void *client_data)
3346 {
3347         off_t pos;
3348         (void)client_data;
3349
3350         if(decoder->private_->file == stdin)
3351                 return FLAC__STREAM_DECODER_TELL_STATUS_UNSUPPORTED;
3352         else if((pos = ftello(decoder->private_->file)) < 0)
3353                 return FLAC__STREAM_DECODER_TELL_STATUS_ERROR;
3354         else {
3355                 *absolute_byte_offset = (FLAC__uint64)pos;
3356                 return FLAC__STREAM_DECODER_TELL_STATUS_OK;
3357         }
3358 }
3359
3360 FLAC__StreamDecoderLengthStatus file_length_callback_(const FLAC__StreamDecoder *decoder, FLAC__uint64 *stream_length, void *client_data)
3361 {
3362         struct stat filestats;
3363         (void)client_data;
3364
3365         if(decoder->private_->file == stdin)
3366                 return FLAC__STREAM_DECODER_LENGTH_STATUS_UNSUPPORTED;
3367         else if(fstat(fileno(decoder->private_->file), &filestats) != 0)
3368                 return FLAC__STREAM_DECODER_LENGTH_STATUS_ERROR;
3369         else {
3370                 *stream_length = (FLAC__uint64)filestats.st_size;
3371                 return FLAC__STREAM_DECODER_LENGTH_STATUS_OK;
3372         }
3373 }
3374
3375 FLAC__bool file_eof_callback_(const FLAC__StreamDecoder *decoder, void *client_data)
3376 {
3377         (void)client_data;
3378
3379         return feof(decoder->private_->file)? true : false;
3380 }