move the new public get_decoder_client_data function to public header.

[flac.git] / src / libFLAC / stream_decoder.c

/* libFLAC - Free Lossless Audio Codec library
 * Copyright (C) 2000-2009  Josh Coalson
 * Copyright (C) 2011-2016  Xiph.Org Foundation
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *
 * - Redistributions in binary form must reproduce the above copyright
 * notice, this list of conditions and the following disclaimer in the
 * documentation and/or other materials provided with the distribution.
 *
 * - Neither the name of the Xiph.org Foundation nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#ifdef HAVE_CONFIG_H
#  include <config.h>
#endif

#include <stdio.h>
#include <stdlib.h> /* for malloc() */
#include <string.h> /* for memset/memcpy() */
#include <sys/stat.h> /* for stat() */
#include <sys/types.h> /* for off_t */
#include "share/compat.h"
#include "FLAC/assert.h"
#include "share/alloc.h"
#include "protected/stream_decoder.h"
#include "private/bitreader.h"
#include "private/bitmath.h"
#include "private/cpu.h"
#include "private/crc.h"
#include "private/fixed.h"
#include "private/format.h"
#include "private/lpc.h"
#include "private/md5.h"
#include "private/memory.h"
#include "private/macros.h"


/* technically this should be in an "export.c" but this is convenient enough */
FLAC_API int FLAC_API_SUPPORTS_OGG_FLAC = FLAC__HAS_OGG;


/***********************************************************************
 *
 * Private static data
 *
 ***********************************************************************/

static const FLAC__byte ID3V2_TAG_[3] = { 'I', 'D', '3' };

/***********************************************************************
 *
 * Private class method prototypes
 *
 ***********************************************************************/

static void set_defaults_(FLAC__StreamDecoder *decoder);
static FILE *get_binary_stdin_(void);
static FLAC__bool allocate_output_(FLAC__StreamDecoder *decoder, uint32_t size, uint32_t channels);
static FLAC__bool has_id_filtered_(FLAC__StreamDecoder *decoder, FLAC__byte *id);
static FLAC__bool find_metadata_(FLAC__StreamDecoder *decoder);
static FLAC__bool read_metadata_(FLAC__StreamDecoder *decoder);
static FLAC__bool read_metadata_streaminfo_(FLAC__StreamDecoder *decoder, FLAC__bool is_last, uint32_t length);
static FLAC__bool read_metadata_seektable_(FLAC__StreamDecoder *decoder, FLAC__bool is_last, uint32_t length);
static FLAC__bool read_metadata_vorbiscomment_(FLAC__StreamDecoder *decoder, FLAC__StreamMetadata_VorbisComment *obj, uint32_t length);
static FLAC__bool read_metadata_cuesheet_(FLAC__StreamDecoder *decoder, FLAC__StreamMetadata_CueSheet *obj);
static FLAC__bool read_metadata_picture_(FLAC__StreamDecoder *decoder, FLAC__StreamMetadata_Picture *obj);
static FLAC__bool skip_id3v2_tag_(FLAC__StreamDecoder *decoder);
static FLAC__bool frame_sync_(FLAC__StreamDecoder *decoder);
static FLAC__bool read_frame_(FLAC__StreamDecoder *decoder, FLAC__bool *got_a_frame, FLAC__bool do_full_decode);
static FLAC__bool read_frame_header_(FLAC__StreamDecoder *decoder);
static FLAC__bool read_subframe_(FLAC__StreamDecoder *decoder, uint32_t channel, uint32_t bps, FLAC__bool do_full_decode);
static FLAC__bool read_subframe_constant_(FLAC__StreamDecoder *decoder, uint32_t channel, uint32_t bps, FLAC__bool do_full_decode);
static FLAC__bool read_subframe_fixed_(FLAC__StreamDecoder *decoder, uint32_t channel, uint32_t bps, const uint32_t order, FLAC__bool do_full_decode);
static FLAC__bool read_subframe_lpc_(FLAC__StreamDecoder *decoder, uint32_t channel, uint32_t bps, const uint32_t order, FLAC__bool do_full_decode);
static FLAC__bool read_subframe_verbatim_(FLAC__StreamDecoder *decoder, uint32_t channel, uint32_t bps, FLAC__bool do_full_decode);
static FLAC__bool read_residual_partitioned_rice_(FLAC__StreamDecoder *decoder, uint32_t predictor_order, uint32_t partition_order, FLAC__EntropyCodingMethod_PartitionedRiceContents *partitioned_rice_contents, FLAC__int32 *residual, FLAC__bool is_extended);
static FLAC__bool read_zero_padding_(FLAC__StreamDecoder *decoder);
static FLAC__bool read_callback_(FLAC__byte buffer[], size_t *bytes, void *client_data);
#if FLAC__HAS_OGG
static FLAC__StreamDecoderReadStatus read_callback_ogg_aspect_(const FLAC__StreamDecoder *decoder, FLAC__byte buffer[], size_t *bytes);
static FLAC__OggDecoderAspectReadStatus read_callback_proxy_(const void *void_decoder, FLAC__byte buffer[], size_t *bytes, void *client_data);
#endif
static FLAC__StreamDecoderWriteStatus write_audio_frame_to_client_(FLAC__StreamDecoder *decoder, const FLAC__Frame *frame, const FLAC__int32 * const buffer[]);
static void send_error_to_client_(const FLAC__StreamDecoder *decoder, FLAC__StreamDecoderErrorStatus status);
static FLAC__bool seek_to_absolute_sample_(FLAC__StreamDecoder *decoder, FLAC__uint64 stream_length, FLAC__uint64 target_sample);
#if FLAC__HAS_OGG
static FLAC__bool seek_to_absolute_sample_ogg_(FLAC__StreamDecoder *decoder, FLAC__uint64 stream_length, FLAC__uint64 target_sample);
#endif
static FLAC__StreamDecoderReadStatus file_read_callback_(const FLAC__StreamDecoder *decoder, FLAC__byte buffer[], size_t *bytes, void *client_data);
static FLAC__StreamDecoderSeekStatus file_seek_callback_(const FLAC__StreamDecoder *decoder, FLAC__uint64 absolute_byte_offset, void *client_data);
static FLAC__StreamDecoderTellStatus file_tell_callback_(const FLAC__StreamDecoder *decoder, FLAC__uint64 *absolute_byte_offset, void *client_data);
static FLAC__StreamDecoderLengthStatus file_length_callback_(const FLAC__StreamDecoder *decoder, FLAC__uint64 *stream_length, void *client_data);
static FLAC__bool file_eof_callback_(const FLAC__StreamDecoder *decoder, void *client_data);

/***********************************************************************
 *
 * Private class data
 *
 ***********************************************************************/

typedef struct FLAC__StreamDecoderPrivate {
        FLAC__bool is_ogg;
        FLAC__StreamDecoderReadCallback read_callback;
        FLAC__StreamDecoderSeekCallback seek_callback;
        FLAC__StreamDecoderTellCallback tell_callback;
        FLAC__StreamDecoderLengthCallback length_callback;
        FLAC__StreamDecoderEofCallback eof_callback;
        FLAC__StreamDecoderWriteCallback write_callback;
        FLAC__StreamDecoderMetadataCallback metadata_callback;
        FLAC__StreamDecoderErrorCallback error_callback;
        /* generic 32-bit datapath: */
        void (*local_lpc_restore_signal)(const FLAC__int32 residual[], uint32_t data_len, const FLAC__int32 qlp_coeff[], uint32_t order, int lp_quantization, FLAC__int32 data[]);
        /* generic 64-bit datapath: */
        void (*local_lpc_restore_signal_64bit)(const FLAC__int32 residual[], uint32_t data_len, const FLAC__int32 qlp_coeff[], uint32_t order, int lp_quantization, FLAC__int32 data[]);
        /* for use when the signal is <= 16 bits-per-sample, or <= 15 bits-per-sample on a side channel (which requires 1 extra bit): */
        void (*local_lpc_restore_signal_16bit)(const FLAC__int32 residual[], uint32_t data_len, const FLAC__int32 qlp_coeff[], uint32_t order, int lp_quantization, FLAC__int32 data[]);
        void *client_data;
        FILE *file; /* only used if FLAC__stream_decoder_init_file()/FLAC__stream_decoder_init_file() called, else NULL */
        FLAC__BitReader *input;
        FLAC__int32 *output[FLAC__MAX_CHANNELS];
        FLAC__int32 *residual[FLAC__MAX_CHANNELS]; /* WATCHOUT: these are the aligned pointers; the real pointers that should be free()'d are residual_unaligned[] below */
        FLAC__EntropyCodingMethod_PartitionedRiceContents partitioned_rice_contents[FLAC__MAX_CHANNELS];
        uint32_t output_capacity, output_channels;
        FLAC__uint32 fixed_block_size, next_fixed_block_size;
        FLAC__uint64 samples_decoded;
        FLAC__bool has_stream_info, has_seek_table;
        FLAC__StreamMetadata stream_info;
        FLAC__StreamMetadata seek_table;
        FLAC__bool metadata_filter[128]; /* MAGIC number 128 == total number of metadata block types == 1 << 7 */
        FLAC__byte *metadata_filter_ids;
        size_t metadata_filter_ids_count, metadata_filter_ids_capacity; /* units for both are IDs, not bytes */
        FLAC__Frame frame;
        FLAC__bool cached; /* true if there is a byte in lookahead */
        FLAC__CPUInfo cpuinfo;
        FLAC__byte header_warmup[2]; /* contains the sync code and reserved bits */
        FLAC__byte lookahead; /* temp storage when we need to look ahead one byte in the stream */
        /* unaligned (original) pointers to allocated data */
        FLAC__int32 *residual_unaligned[FLAC__MAX_CHANNELS];
        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 */
        FLAC__bool internal_reset_hack; /* used only during init() so we can call reset to set up the decoder without rewinding the input */
        FLAC__bool is_seeking;
        FLAC__MD5Context md5context;
        FLAC__byte computed_md5sum[16]; /* this is the sum we computed from the decoded data */
        /* (the rest of these are only used for seeking) */
        FLAC__Frame last_frame; /* holds the info of the last frame we seeked to */
        FLAC__uint64 first_frame_offset; /* hint to the seek routine of where in the stream the first audio frame starts */
        FLAC__uint64 target_sample;
        uint32_t unparseable_frame_count; /* used to tell whether we're decoding a future version of FLAC or just got a bad sync */
        FLAC__bool got_a_frame; /* hack needed in Ogg FLAC seek routine to check when process_single() actually writes a frame */
} FLAC__StreamDecoderPrivate;

/***********************************************************************
 *
 * Public static class data
 *
 ***********************************************************************/

FLAC_API const char * const FLAC__StreamDecoderStateString[] = {
        "FLAC__STREAM_DECODER_SEARCH_FOR_METADATA",
        "FLAC__STREAM_DECODER_READ_METADATA",
        "FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC",
        "FLAC__STREAM_DECODER_READ_FRAME",
        "FLAC__STREAM_DECODER_END_OF_STREAM",
        "FLAC__STREAM_DECODER_OGG_ERROR",
        "FLAC__STREAM_DECODER_SEEK_ERROR",
        "FLAC__STREAM_DECODER_ABORTED",
        "FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR",
        "FLAC__STREAM_DECODER_UNINITIALIZED"
};

FLAC_API const char * const FLAC__StreamDecoderInitStatusString[] = {
        "FLAC__STREAM_DECODER_INIT_STATUS_OK",
        "FLAC__STREAM_DECODER_INIT_STATUS_UNSUPPORTED_CONTAINER",
        "FLAC__STREAM_DECODER_INIT_STATUS_INVALID_CALLBACKS",
        "FLAC__STREAM_DECODER_INIT_STATUS_MEMORY_ALLOCATION_ERROR",
        "FLAC__STREAM_DECODER_INIT_STATUS_ERROR_OPENING_FILE",
        "FLAC__STREAM_DECODER_INIT_STATUS_ALREADY_INITIALIZED"
};

FLAC_API const char * const FLAC__StreamDecoderReadStatusString[] = {
        "FLAC__STREAM_DECODER_READ_STATUS_CONTINUE",
        "FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM",
        "FLAC__STREAM_DECODER_READ_STATUS_ABORT"
};

FLAC_API const char * const FLAC__StreamDecoderSeekStatusString[] = {
        "FLAC__STREAM_DECODER_SEEK_STATUS_OK",
        "FLAC__STREAM_DECODER_SEEK_STATUS_ERROR",
        "FLAC__STREAM_DECODER_SEEK_STATUS_UNSUPPORTED"
};

FLAC_API const char * const FLAC__StreamDecoderTellStatusString[] = {
        "FLAC__STREAM_DECODER_TELL_STATUS_OK",
        "FLAC__STREAM_DECODER_TELL_STATUS_ERROR",
        "FLAC__STREAM_DECODER_TELL_STATUS_UNSUPPORTED"
};

FLAC_API const char * const FLAC__StreamDecoderLengthStatusString[] = {
        "FLAC__STREAM_DECODER_LENGTH_STATUS_OK",
        "FLAC__STREAM_DECODER_LENGTH_STATUS_ERROR",
        "FLAC__STREAM_DECODER_LENGTH_STATUS_UNSUPPORTED"
};

FLAC_API const char * const FLAC__StreamDecoderWriteStatusString[] = {
        "FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE",
        "FLAC__STREAM_DECODER_WRITE_STATUS_ABORT"
};

FLAC_API const char * const FLAC__StreamDecoderErrorStatusString[] = {
        "FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC",
        "FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER",
        "FLAC__STREAM_DECODER_ERROR_STATUS_FRAME_CRC_MISMATCH",
        "FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM"
};

/***********************************************************************
 *
 * Class constructor/destructor
 *
 ***********************************************************************/
FLAC_API FLAC__StreamDecoder *FLAC__stream_decoder_new(void)
{
        FLAC__StreamDecoder *decoder;
        uint32_t i;

        FLAC__ASSERT(sizeof(int) >= 4); /* we want to die right away if this is not true */

        decoder = calloc(1, sizeof(FLAC__StreamDecoder));
        if(decoder == 0) {
                return 0;
        }

        decoder->protected_ = calloc(1, sizeof(FLAC__StreamDecoderProtected));
        if(decoder->protected_ == 0) {
                free(decoder);
                return 0;
        }

        decoder->private_ = calloc(1, sizeof(FLAC__StreamDecoderPrivate));
        if(decoder->private_ == 0) {
                free(decoder->protected_);
                free(decoder);
                return 0;
        }

        decoder->private_->input = FLAC__bitreader_new();
        if(decoder->private_->input == 0) {
                free(decoder->private_);
                free(decoder->protected_);
                free(decoder);
                return 0;
        }

        decoder->private_->metadata_filter_ids_capacity = 16;
        if(0 == (decoder->private_->metadata_filter_ids = malloc((FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8) * decoder->private_->metadata_filter_ids_capacity))) {
                FLAC__bitreader_delete(decoder->private_->input);
                free(decoder->private_);
                free(decoder->protected_);
                free(decoder);
                return 0;
        }

        for(i = 0; i < FLAC__MAX_CHANNELS; i++) {
                decoder->private_->output[i] = 0;
                decoder->private_->residual_unaligned[i] = decoder->private_->residual[i] = 0;
        }

        decoder->private_->output_capacity = 0;
        decoder->private_->output_channels = 0;
        decoder->private_->has_seek_table = false;

        for(i = 0; i < FLAC__MAX_CHANNELS; i++)
                FLAC__format_entropy_coding_method_partitioned_rice_contents_init(&decoder->private_->partitioned_rice_contents[i]);

        decoder->private_->file = 0;

        set_defaults_(decoder);

        decoder->protected_->state = FLAC__STREAM_DECODER_UNINITIALIZED;

        return decoder;
}

FLAC_API void FLAC__stream_decoder_delete(FLAC__StreamDecoder *decoder)
{
        uint32_t i;

        if (decoder == NULL)
                return ;

        FLAC__ASSERT(0 != decoder->protected_);
        FLAC__ASSERT(0 != decoder->private_);
        FLAC__ASSERT(0 != decoder->private_->input);

        (void)FLAC__stream_decoder_finish(decoder);

        if(0 != decoder->private_->metadata_filter_ids)
                free(decoder->private_->metadata_filter_ids);

        FLAC__bitreader_delete(decoder->private_->input);

        for(i = 0; i < FLAC__MAX_CHANNELS; i++)
                FLAC__format_entropy_coding_method_partitioned_rice_contents_clear(&decoder->private_->partitioned_rice_contents[i]);

        free(decoder->private_);
        free(decoder->protected_);
        free(decoder);
}

/***********************************************************************
 *
 * Public class methods
 *
 ***********************************************************************/

static FLAC__StreamDecoderInitStatus init_stream_internal_(
        FLAC__StreamDecoder *decoder,
        FLAC__StreamDecoderReadCallback read_callback,
        FLAC__StreamDecoderSeekCallback seek_callback,
        FLAC__StreamDecoderTellCallback tell_callback,
        FLAC__StreamDecoderLengthCallback length_callback,
        FLAC__StreamDecoderEofCallback eof_callback,
        FLAC__StreamDecoderWriteCallback write_callback,
        FLAC__StreamDecoderMetadataCallback metadata_callback,
        FLAC__StreamDecoderErrorCallback error_callback,
        void *client_data,
        FLAC__bool is_ogg
)
{
        FLAC__ASSERT(0 != decoder);

        if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
                return FLAC__STREAM_DECODER_INIT_STATUS_ALREADY_INITIALIZED;

        if(FLAC__HAS_OGG == 0 && is_ogg)
                return FLAC__STREAM_DECODER_INIT_STATUS_UNSUPPORTED_CONTAINER;

        if(
                0 == read_callback ||
                0 == write_callback ||
                0 == error_callback ||
                (seek_callback && (0 == tell_callback || 0 == length_callback || 0 == eof_callback))
        )
                return FLAC__STREAM_DECODER_INIT_STATUS_INVALID_CALLBACKS;

#if FLAC__HAS_OGG
        decoder->private_->is_ogg = is_ogg;
        if(is_ogg && !FLAC__ogg_decoder_aspect_init(&decoder->protected_->ogg_decoder_aspect))
                return decoder->protected_->initstate = FLAC__STREAM_DECODER_INIT_STATUS_ERROR_OPENING_FILE;
#endif

        /*
         * get the CPU info and set the function pointers
         */
        FLAC__cpu_info(&decoder->private_->cpuinfo);
        /* first default to the non-asm routines */
        decoder->private_->local_lpc_restore_signal = FLAC__lpc_restore_signal;
        decoder->private_->local_lpc_restore_signal_64bit = FLAC__lpc_restore_signal_wide;
        decoder->private_->local_lpc_restore_signal_16bit = FLAC__lpc_restore_signal;
        /* now override with asm where appropriate */
#ifndef FLAC__NO_ASM
        if(decoder->private_->cpuinfo.use_asm) {
#ifdef FLAC__CPU_IA32
                FLAC__ASSERT(decoder->private_->cpuinfo.type == FLAC__CPUINFO_TYPE_IA32);
#ifdef FLAC__HAS_NASM
                decoder->private_->local_lpc_restore_signal_64bit = FLAC__lpc_restore_signal_wide_asm_ia32; /* OPT_IA32: was really necessary for GCC < 4.9 */
                if (decoder->private_->cpuinfo.x86.mmx) {
                        decoder->private_->local_lpc_restore_signal = FLAC__lpc_restore_signal_asm_ia32;
                        decoder->private_->local_lpc_restore_signal_16bit = FLAC__lpc_restore_signal_asm_ia32_mmx;
                }
                else {
                        decoder->private_->local_lpc_restore_signal = FLAC__lpc_restore_signal_asm_ia32;
                        decoder->private_->local_lpc_restore_signal_16bit = FLAC__lpc_restore_signal_asm_ia32;
                }
#endif
#if FLAC__HAS_X86INTRIN && ! defined FLAC__INTEGER_ONLY_LIBRARY
# if defined FLAC__SSE4_1_SUPPORTED
                if (decoder->private_->cpuinfo.x86.sse41) {
#  if !defined FLAC__HAS_NASM  /* these are not undoubtedly faster than their MMX ASM counterparts */
                        decoder->private_->local_lpc_restore_signal = FLAC__lpc_restore_signal_intrin_sse41;
                        decoder->private_->local_lpc_restore_signal_16bit = FLAC__lpc_restore_signal_16_intrin_sse41;
#  endif
                        decoder->private_->local_lpc_restore_signal_64bit = FLAC__lpc_restore_signal_wide_intrin_sse41;
                }
# endif
#endif
#elif defined FLAC__CPU_X86_64
                FLAC__ASSERT(decoder->private_->cpuinfo.type == FLAC__CPUINFO_TYPE_X86_64);
                /* No useful SSE optimizations yet */
#endif
        }
#endif

        /* from here on, errors are fatal */

        if(!FLAC__bitreader_init(decoder->private_->input, read_callback_, decoder)) {
                decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
                return FLAC__STREAM_DECODER_INIT_STATUS_MEMORY_ALLOCATION_ERROR;
        }

        decoder->private_->read_callback = read_callback;
        decoder->private_->seek_callback = seek_callback;
        decoder->private_->tell_callback = tell_callback;
        decoder->private_->length_callback = length_callback;
        decoder->private_->eof_callback = eof_callback;
        decoder->private_->write_callback = write_callback;
        decoder->private_->metadata_callback = metadata_callback;
        decoder->private_->error_callback = error_callback;
        decoder->private_->client_data = client_data;
        decoder->private_->fixed_block_size = decoder->private_->next_fixed_block_size = 0;
        decoder->private_->samples_decoded = 0;
        decoder->private_->has_stream_info = false;
        decoder->private_->cached = false;

        decoder->private_->do_md5_checking = decoder->protected_->md5_checking;
        decoder->private_->is_seeking = false;

        decoder->private_->internal_reset_hack = true; /* so the following reset does not try to rewind the input */
        if(!FLAC__stream_decoder_reset(decoder)) {
                /* above call sets the state for us */
                return FLAC__STREAM_DECODER_INIT_STATUS_MEMORY_ALLOCATION_ERROR;
        }

        return FLAC__STREAM_DECODER_INIT_STATUS_OK;
}

FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_stream(
        FLAC__StreamDecoder *decoder,
        FLAC__StreamDecoderReadCallback read_callback,
        FLAC__StreamDecoderSeekCallback seek_callback,
        FLAC__StreamDecoderTellCallback tell_callback,
        FLAC__StreamDecoderLengthCallback length_callback,
        FLAC__StreamDecoderEofCallback eof_callback,
        FLAC__StreamDecoderWriteCallback write_callback,
        FLAC__StreamDecoderMetadataCallback metadata_callback,
        FLAC__StreamDecoderErrorCallback error_callback,
        void *client_data
)
{
        return init_stream_internal_(
                decoder,
                read_callback,
                seek_callback,
                tell_callback,
                length_callback,
                eof_callback,
                write_callback,
                metadata_callback,
                error_callback,
                client_data,
                /*is_ogg=*/false
        );
}

FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_ogg_stream(
        FLAC__StreamDecoder *decoder,
        FLAC__StreamDecoderReadCallback read_callback,
        FLAC__StreamDecoderSeekCallback seek_callback,
        FLAC__StreamDecoderTellCallback tell_callback,
        FLAC__StreamDecoderLengthCallback length_callback,
        FLAC__StreamDecoderEofCallback eof_callback,
        FLAC__StreamDecoderWriteCallback write_callback,
        FLAC__StreamDecoderMetadataCallback metadata_callback,
        FLAC__StreamDecoderErrorCallback error_callback,
        void *client_data
)
{
        return init_stream_internal_(
                decoder,
                read_callback,
                seek_callback,
                tell_callback,
                length_callback,
                eof_callback,
                write_callback,
                metadata_callback,
                error_callback,
                client_data,
                /*is_ogg=*/true
        );
}

static FLAC__StreamDecoderInitStatus init_FILE_internal_(
        FLAC__StreamDecoder *decoder,
        FILE *file,
        FLAC__StreamDecoderWriteCallback write_callback,
        FLAC__StreamDecoderMetadataCallback metadata_callback,
        FLAC__StreamDecoderErrorCallback error_callback,
        void *client_data,
        FLAC__bool is_ogg
)
{
        FLAC__ASSERT(0 != decoder);
        FLAC__ASSERT(0 != file);

        if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
                return decoder->protected_->initstate = FLAC__STREAM_DECODER_INIT_STATUS_ALREADY_INITIALIZED;

        if(0 == write_callback || 0 == error_callback)
                return decoder->protected_->initstate = FLAC__STREAM_DECODER_INIT_STATUS_INVALID_CALLBACKS;

        /*
         * To make sure that our file does not go unclosed after an error, we
         * must assign the FILE pointer before any further error can occur in
         * this routine.
         */
        if(file == stdin)
                file = get_binary_stdin_(); /* just to be safe */

        decoder->private_->file = file;

        return init_stream_internal_(
                decoder,
                file_read_callback_,
                decoder->private_->file == stdin? 0: file_seek_callback_,
                decoder->private_->file == stdin? 0: file_tell_callback_,
                decoder->private_->file == stdin? 0: file_length_callback_,
                file_eof_callback_,
                write_callback,
                metadata_callback,
                error_callback,
                client_data,
                is_ogg
        );
}

FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_FILE(
        FLAC__StreamDecoder *decoder,
        FILE *file,
        FLAC__StreamDecoderWriteCallback write_callback,
        FLAC__StreamDecoderMetadataCallback metadata_callback,
        FLAC__StreamDecoderErrorCallback error_callback,
        void *client_data
)
{
        return init_FILE_internal_(decoder, file, write_callback, metadata_callback, error_callback, client_data, /*is_ogg=*/false);
}

FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_ogg_FILE(
        FLAC__StreamDecoder *decoder,
        FILE *file,
        FLAC__StreamDecoderWriteCallback write_callback,
        FLAC__StreamDecoderMetadataCallback metadata_callback,
        FLAC__StreamDecoderErrorCallback error_callback,
        void *client_data
)
{
        return init_FILE_internal_(decoder, file, write_callback, metadata_callback, error_callback, client_data, /*is_ogg=*/true);
}

static FLAC__StreamDecoderInitStatus init_file_internal_(
        FLAC__StreamDecoder *decoder,
        const char *filename,
        FLAC__StreamDecoderWriteCallback write_callback,
        FLAC__StreamDecoderMetadataCallback metadata_callback,
        FLAC__StreamDecoderErrorCallback error_callback,
        void *client_data,
        FLAC__bool is_ogg
)
{
        FILE *file;

        FLAC__ASSERT(0 != decoder);

        /*
         * To make sure that our file does not go unclosed after an error, we
         * have to do the same entrance checks here that are later performed
         * in FLAC__stream_decoder_init_FILE() before the FILE* is assigned.
         */
        if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
                return decoder->protected_->initstate = FLAC__STREAM_DECODER_INIT_STATUS_ALREADY_INITIALIZED;

        if(0 == write_callback || 0 == error_callback)
                return decoder->protected_->initstate = FLAC__STREAM_DECODER_INIT_STATUS_INVALID_CALLBACKS;

        file = filename? flac_fopen(filename, "rb") : stdin;

        if(0 == file)
                return FLAC__STREAM_DECODER_INIT_STATUS_ERROR_OPENING_FILE;

        return init_FILE_internal_(decoder, file, write_callback, metadata_callback, error_callback, client_data, is_ogg);
}

FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_file(
        FLAC__StreamDecoder *decoder,
        const char *filename,
        FLAC__StreamDecoderWriteCallback write_callback,
        FLAC__StreamDecoderMetadataCallback metadata_callback,
        FLAC__StreamDecoderErrorCallback error_callback,
        void *client_data
)
{
        return init_file_internal_(decoder, filename, write_callback, metadata_callback, error_callback, client_data, /*is_ogg=*/false);
}

FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_ogg_file(
        FLAC__StreamDecoder *decoder,
        const char *filename,
        FLAC__StreamDecoderWriteCallback write_callback,
        FLAC__StreamDecoderMetadataCallback metadata_callback,
        FLAC__StreamDecoderErrorCallback error_callback,
        void *client_data
)
{
        return init_file_internal_(decoder, filename, write_callback, metadata_callback, error_callback, client_data, /*is_ogg=*/true);
}

FLAC_API FLAC__bool FLAC__stream_decoder_finish(FLAC__StreamDecoder *decoder)
{
        FLAC__bool md5_failed = false;
        uint32_t i;

        FLAC__ASSERT(0 != decoder);
        FLAC__ASSERT(0 != decoder->private_);
        FLAC__ASSERT(0 != decoder->protected_);

        if(decoder->protected_->state == FLAC__STREAM_DECODER_UNINITIALIZED)
                return true;

        /* see the comment in FLAC__stream_decoder_reset() as to why we
         * always call FLAC__MD5Final()
         */
        FLAC__MD5Final(decoder->private_->computed_md5sum, &decoder->private_->md5context);

        free(decoder->private_->seek_table.data.seek_table.points);
        decoder->private_->seek_table.data.seek_table.points = 0;
        decoder->private_->has_seek_table = false;

        FLAC__bitreader_free(decoder->private_->input);
        for(i = 0; i < FLAC__MAX_CHANNELS; i++) {
                /* WATCHOUT:
                 * FLAC__lpc_restore_signal_asm_ia32_mmx() and ..._intrin_sseN()
                 * require that the output arrays have a buffer of up to 3 zeroes
                 * in front (at negative indices) for alignment purposes;
                 * we use 4 to keep the data well-aligned.
                 */
                if(0 != decoder->private_->output[i]) {
                        free(decoder->private_->output[i]-4);
                        decoder->private_->output[i] = 0;
                }
                if(0 != decoder->private_->residual_unaligned[i]) {
                        free(decoder->private_->residual_unaligned[i]);
                        decoder->private_->residual_unaligned[i] = decoder->private_->residual[i] = 0;
                }
        }
        decoder->private_->output_capacity = 0;
        decoder->private_->output_channels = 0;

#if FLAC__HAS_OGG
        if(decoder->private_->is_ogg)
                FLAC__ogg_decoder_aspect_finish(&decoder->protected_->ogg_decoder_aspect);
#endif

        if(0 != decoder->private_->file) {
                if(decoder->private_->file != stdin)
                        fclose(decoder->private_->file);
                decoder->private_->file = 0;
        }

        if(decoder->private_->do_md5_checking) {
                if(memcmp(decoder->private_->stream_info.data.stream_info.md5sum, decoder->private_->computed_md5sum, 16))
                        md5_failed = true;
        }
        decoder->private_->is_seeking = false;

        set_defaults_(decoder);

        decoder->protected_->state = FLAC__STREAM_DECODER_UNINITIALIZED;

        return !md5_failed;
}

FLAC_API FLAC__bool FLAC__stream_decoder_set_ogg_serial_number(FLAC__StreamDecoder *decoder, long value)
{
        FLAC__ASSERT(0 != decoder);
        FLAC__ASSERT(0 != decoder->private_);
        FLAC__ASSERT(0 != decoder->protected_);
        if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
                return false;
#if FLAC__HAS_OGG
        /* can't check decoder->private_->is_ogg since that's not set until init time */
        FLAC__ogg_decoder_aspect_set_serial_number(&decoder->protected_->ogg_decoder_aspect, value);
        return true;
#else
        (void)value;
        return false;
#endif
}

FLAC_API FLAC__bool FLAC__stream_decoder_set_md5_checking(FLAC__StreamDecoder *decoder, FLAC__bool value)
{
        FLAC__ASSERT(0 != decoder);
        FLAC__ASSERT(0 != decoder->protected_);
        if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
                return false;
        decoder->protected_->md5_checking = value;
        return true;
}

FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_respond(FLAC__StreamDecoder *decoder, FLAC__MetadataType type)
{
        FLAC__ASSERT(0 != decoder);
        FLAC__ASSERT(0 != decoder->private_);
        FLAC__ASSERT(0 != decoder->protected_);
        FLAC__ASSERT((uint32_t)type <= FLAC__MAX_METADATA_TYPE_CODE);
        /* double protection */
        if((uint32_t)type > FLAC__MAX_METADATA_TYPE_CODE)
                return false;
        if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
                return false;
        decoder->private_->metadata_filter[type] = true;
        if(type == FLAC__METADATA_TYPE_APPLICATION)
                decoder->private_->metadata_filter_ids_count = 0;
        return true;
}

FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_respond_application(FLAC__StreamDecoder *decoder, const FLAC__byte id[4])
{
        FLAC__ASSERT(0 != decoder);
        FLAC__ASSERT(0 != decoder->private_);
        FLAC__ASSERT(0 != decoder->protected_);
        FLAC__ASSERT(0 != id);
        if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
                return false;

        if(decoder->private_->metadata_filter[FLAC__METADATA_TYPE_APPLICATION])
                return true;

        FLAC__ASSERT(0 != decoder->private_->metadata_filter_ids);

        if(decoder->private_->metadata_filter_ids_count == decoder->private_->metadata_filter_ids_capacity) {
                if(0 == (decoder->private_->metadata_filter_ids = safe_realloc_mul_2op_(decoder->private_->metadata_filter_ids, decoder->private_->metadata_filter_ids_capacity, /*times*/2))) {
                        decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
                        return false;
                }
                decoder->private_->metadata_filter_ids_capacity *= 2;
        }

        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));
        decoder->private_->metadata_filter_ids_count++;

        return true;
}

FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_respond_all(FLAC__StreamDecoder *decoder)
{
        uint32_t i;
        FLAC__ASSERT(0 != decoder);
        FLAC__ASSERT(0 != decoder->private_);
        FLAC__ASSERT(0 != decoder->protected_);
        if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
                return false;
        for(i = 0; i < sizeof(decoder->private_->metadata_filter) / sizeof(decoder->private_->metadata_filter[0]); i++)
                decoder->private_->metadata_filter[i] = true;
        decoder->private_->metadata_filter_ids_count = 0;
        return true;
}

FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_ignore(FLAC__StreamDecoder *decoder, FLAC__MetadataType type)
{
        FLAC__ASSERT(0 != decoder);
        FLAC__ASSERT(0 != decoder->private_);
        FLAC__ASSERT(0 != decoder->protected_);
        FLAC__ASSERT((uint32_t)type <= FLAC__MAX_METADATA_TYPE_CODE);
        /* double protection */
        if((uint32_t)type > FLAC__MAX_METADATA_TYPE_CODE)
                return false;
        if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
                return false;
        decoder->private_->metadata_filter[type] = false;
        if(type == FLAC__METADATA_TYPE_APPLICATION)
                decoder->private_->metadata_filter_ids_count = 0;
        return true;
}

FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_ignore_application(FLAC__StreamDecoder *decoder, const FLAC__byte id[4])
{
        FLAC__ASSERT(0 != decoder);
        FLAC__ASSERT(0 != decoder->private_);
        FLAC__ASSERT(0 != decoder->protected_);
        FLAC__ASSERT(0 != id);
        if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
                return false;

        if(!decoder->private_->metadata_filter[FLAC__METADATA_TYPE_APPLICATION])
                return true;

        FLAC__ASSERT(0 != decoder->private_->metadata_filter_ids);

        if(decoder->private_->metadata_filter_ids_count == decoder->private_->metadata_filter_ids_capacity) {
                if(0 == (decoder->private_->metadata_filter_ids = safe_realloc_mul_2op_(decoder->private_->metadata_filter_ids, decoder->private_->metadata_filter_ids_capacity, /*times*/2))) {
                        decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
                        return false;
                }
                decoder->private_->metadata_filter_ids_capacity *= 2;
        }

        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));
        decoder->private_->metadata_filter_ids_count++;

        return true;
}

FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_ignore_all(FLAC__StreamDecoder *decoder)
{
        FLAC__ASSERT(0 != decoder);
        FLAC__ASSERT(0 != decoder->private_);
        FLAC__ASSERT(0 != decoder->protected_);
        if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
                return false;
        memset(decoder->private_->metadata_filter, 0, sizeof(decoder->private_->metadata_filter));
        decoder->private_->metadata_filter_ids_count = 0;
        return true;
}

FLAC_API FLAC__StreamDecoderState FLAC__stream_decoder_get_state(const FLAC__StreamDecoder *decoder)
{
        FLAC__ASSERT(0 != decoder);
        FLAC__ASSERT(0 != decoder->protected_);
        return decoder->protected_->state;
}

FLAC_API const char *FLAC__stream_decoder_get_resolved_state_string(const FLAC__StreamDecoder *decoder)
{
        return FLAC__StreamDecoderStateString[decoder->protected_->state];
}

FLAC_API FLAC__bool FLAC__stream_decoder_get_md5_checking(const FLAC__StreamDecoder *decoder)
{
        FLAC__ASSERT(0 != decoder);
        FLAC__ASSERT(0 != decoder->protected_);
        return decoder->protected_->md5_checking;
}

FLAC_API FLAC__uint64 FLAC__stream_decoder_get_total_samples(const FLAC__StreamDecoder *decoder)
{
        FLAC__ASSERT(0 != decoder);
        FLAC__ASSERT(0 != decoder->protected_);
        return decoder->private_->has_stream_info? decoder->private_->stream_info.data.stream_info.total_samples : 0;
}

FLAC_API uint32_t FLAC__stream_decoder_get_channels(const FLAC__StreamDecoder *decoder)
{
        FLAC__ASSERT(0 != decoder);
        FLAC__ASSERT(0 != decoder->protected_);
        return decoder->protected_->channels;
}

FLAC_API FLAC__ChannelAssignment FLAC__stream_decoder_get_channel_assignment(const FLAC__StreamDecoder *decoder)
{
        FLAC__ASSERT(0 != decoder);
        FLAC__ASSERT(0 != decoder->protected_);
        return decoder->protected_->channel_assignment;
}

FLAC_API uint32_t FLAC__stream_decoder_get_bits_per_sample(const FLAC__StreamDecoder *decoder)
{
        FLAC__ASSERT(0 != decoder);
        FLAC__ASSERT(0 != decoder->protected_);
        return decoder->protected_->bits_per_sample;
}

FLAC_API uint32_t FLAC__stream_decoder_get_sample_rate(const FLAC__StreamDecoder *decoder)
{
        FLAC__ASSERT(0 != decoder);
        FLAC__ASSERT(0 != decoder->protected_);
        return decoder->protected_->sample_rate;
}

FLAC_API uint32_t FLAC__stream_decoder_get_blocksize(const FLAC__StreamDecoder *decoder)
{
        FLAC__ASSERT(0 != decoder);
        FLAC__ASSERT(0 != decoder->protected_);
        return decoder->protected_->blocksize;
}

FLAC_API FLAC__bool FLAC__stream_decoder_get_decode_position(const FLAC__StreamDecoder *decoder, FLAC__uint64 *position)
{
        FLAC__ASSERT(0 != decoder);
        FLAC__ASSERT(0 != decoder->private_);
        FLAC__ASSERT(0 != position);

        if(FLAC__HAS_OGG && decoder->private_->is_ogg)
                return false;

        if(0 == decoder->private_->tell_callback)
                return false;
        if(decoder->private_->tell_callback(decoder, position, decoder->private_->client_data) != FLAC__STREAM_DECODER_TELL_STATUS_OK)
                return false;
        /* should never happen since all FLAC frames and metadata blocks are byte aligned, but check just in case */
        if(!FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input))
                return false;
        FLAC__ASSERT(*position >= FLAC__stream_decoder_get_input_bytes_unconsumed(decoder));
        *position -= FLAC__stream_decoder_get_input_bytes_unconsumed(decoder);
        return true;
}

FLAC_API FLAC__bool FLAC__stream_decoder_flush(FLAC__StreamDecoder *decoder)
{
        FLAC__ASSERT(0 != decoder);
        FLAC__ASSERT(0 != decoder->private_);
        FLAC__ASSERT(0 != decoder->protected_);

        if(!decoder->private_->internal_reset_hack && decoder->protected_->state == FLAC__STREAM_DECODER_UNINITIALIZED)
                return false;

        decoder->private_->samples_decoded = 0;
        decoder->private_->do_md5_checking = false;

#if FLAC__HAS_OGG
        if(decoder->private_->is_ogg)
                FLAC__ogg_decoder_aspect_flush(&decoder->protected_->ogg_decoder_aspect);
#endif

        if(!FLAC__bitreader_clear(decoder->private_->input)) {
                decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
                return false;
        }
        decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;

        return true;
}

FLAC_API FLAC__bool FLAC__stream_decoder_reset(FLAC__StreamDecoder *decoder)
{
        FLAC__ASSERT(0 != decoder);
        FLAC__ASSERT(0 != decoder->private_);
        FLAC__ASSERT(0 != decoder->protected_);

        if(!FLAC__stream_decoder_flush(decoder)) {
                /* above call sets the state for us */
                return false;
        }

#if FLAC__HAS_OGG
        /*@@@ could go in !internal_reset_hack block below */
        if(decoder->private_->is_ogg)
                FLAC__ogg_decoder_aspect_reset(&decoder->protected_->ogg_decoder_aspect);
#endif

        /* Rewind if necessary.  If FLAC__stream_decoder_init() is calling us,
         * (internal_reset_hack) don't try to rewind since we are already at
         * the beginning of the stream and don't want to fail if the input is
         * not seekable.
         */
        if(!decoder->private_->internal_reset_hack) {
                if(decoder->private_->file == stdin)
                        return false; /* can't rewind stdin, reset fails */
                if(decoder->private_->seek_callback && decoder->private_->seek_callback(decoder, 0, decoder->private_->client_data) == FLAC__STREAM_DECODER_SEEK_STATUS_ERROR)
                        return false; /* seekable and seek fails, reset fails */
        }
        else
                decoder->private_->internal_reset_hack = false;

        decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_METADATA;

        decoder->private_->has_stream_info = false;

        free(decoder->private_->seek_table.data.seek_table.points);
        decoder->private_->seek_table.data.seek_table.points = 0;
        decoder->private_->has_seek_table = false;

        decoder->private_->do_md5_checking = decoder->protected_->md5_checking;
        /*
         * This goes in reset() and not flush() because according to the spec, a
         * fixed-blocksize stream must stay that way through the whole stream.
         */
        decoder->private_->fixed_block_size = decoder->private_->next_fixed_block_size = 0;

        /* We initialize the FLAC__MD5Context even though we may never use it.  This
         * is because md5 checking may be turned on to start and then turned off if
         * a seek occurs.  So we init the context here and finalize it in
         * FLAC__stream_decoder_finish() to make sure things are always cleaned up
         * properly.
         */
        FLAC__MD5Init(&decoder->private_->md5context);

        decoder->private_->first_frame_offset = 0;
        decoder->private_->unparseable_frame_count = 0;

        return true;
}

FLAC_API FLAC__bool FLAC__stream_decoder_process_single(FLAC__StreamDecoder *decoder)
{
        FLAC__bool got_a_frame;
        FLAC__ASSERT(0 != decoder);
        FLAC__ASSERT(0 != decoder->protected_);

        while(1) {
                switch(decoder->protected_->state) {
                        case FLAC__STREAM_DECODER_SEARCH_FOR_METADATA:
                                if(!find_metadata_(decoder))
                                        return false; /* above function sets the status for us */
                                break;
                        case FLAC__STREAM_DECODER_READ_METADATA:
                                if(!read_metadata_(decoder))
                                        return false; /* above function sets the status for us */
                                else
                                        return true;
                        case FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC:
                                if(!frame_sync_(decoder))
                                        return true; /* above function sets the status for us */
                                break;
                        case FLAC__STREAM_DECODER_READ_FRAME:
                                if(!read_frame_(decoder, &got_a_frame, /*do_full_decode=*/true))
                                        return false; /* above function sets the status for us */
                                if(got_a_frame)
                                        return true; /* above function sets the status for us */
                                break;
                        case FLAC__STREAM_DECODER_END_OF_STREAM:
                        case FLAC__STREAM_DECODER_ABORTED:
                                return true;
                        default:
                                FLAC__ASSERT(0);
                                return false;
                }
        }
}

FLAC_API FLAC__bool FLAC__stream_decoder_process_until_end_of_metadata(FLAC__StreamDecoder *decoder)
{
        FLAC__ASSERT(0 != decoder);
        FLAC__ASSERT(0 != decoder->protected_);

        while(1) {
                switch(decoder->protected_->state) {
                        case FLAC__STREAM_DECODER_SEARCH_FOR_METADATA:
                                if(!find_metadata_(decoder))
                                        return false; /* above function sets the status for us */
                                break;
                        case FLAC__STREAM_DECODER_READ_METADATA:
                                if(!read_metadata_(decoder))
                                        return false; /* above function sets the status for us */
                                break;
                        case FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC:
                        case FLAC__STREAM_DECODER_READ_FRAME:
                        case FLAC__STREAM_DECODER_END_OF_STREAM:
                        case FLAC__STREAM_DECODER_ABORTED:
                                return true;
                        default:
                                FLAC__ASSERT(0);
                                return false;
                }
        }
}

FLAC_API FLAC__bool FLAC__stream_decoder_process_until_end_of_stream(FLAC__StreamDecoder *decoder)
{
        FLAC__bool dummy;
        FLAC__ASSERT(0 != decoder);
        FLAC__ASSERT(0 != decoder->protected_);

        while(1) {
                switch(decoder->protected_->state) {
                        case FLAC__STREAM_DECODER_SEARCH_FOR_METADATA:
                                if(!find_metadata_(decoder))
                                        return false; /* above function sets the status for us */
                                break;
                        case FLAC__STREAM_DECODER_READ_METADATA:
                                if(!read_metadata_(decoder))
                                        return false; /* above function sets the status for us */
                                break;
                        case FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC:
                                if(!frame_sync_(decoder))
                                        return true; /* above function sets the status for us */
                                break;
                        case FLAC__STREAM_DECODER_READ_FRAME:
                                if(!read_frame_(decoder, &dummy, /*do_full_decode=*/true))
                                        return false; /* above function sets the status for us */
                                break;
                        case FLAC__STREAM_DECODER_END_OF_STREAM:
                        case FLAC__STREAM_DECODER_ABORTED:
                                return true;
                        default:
                                FLAC__ASSERT(0);
                                return false;
                }
        }
}

FLAC_API FLAC__bool FLAC__stream_decoder_skip_single_frame(FLAC__StreamDecoder *decoder)
{
        FLAC__bool got_a_frame;
        FLAC__ASSERT(0 != decoder);
        FLAC__ASSERT(0 != decoder->protected_);

        while(1) {
                switch(decoder->protected_->state) {
                        case FLAC__STREAM_DECODER_SEARCH_FOR_METADATA:
                        case FLAC__STREAM_DECODER_READ_METADATA:
                                return false; /* above function sets the status for us */
                        case FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC:
                                if(!frame_sync_(decoder))
                                        return true; /* above function sets the status for us */
                                break;
                        case FLAC__STREAM_DECODER_READ_FRAME:
                                if(!read_frame_(decoder, &got_a_frame, /*do_full_decode=*/false))
                                        return false; /* above function sets the status for us */
                                if(got_a_frame)
                                        return true; /* above function sets the status for us */
                                break;
                        case FLAC__STREAM_DECODER_END_OF_STREAM:
                        case FLAC__STREAM_DECODER_ABORTED:
                                return true;
                        default:
                                FLAC__ASSERT(0);
                                return false;
                }
        }
}

FLAC_API FLAC__bool FLAC__stream_decoder_seek_absolute(FLAC__StreamDecoder *decoder, FLAC__uint64 sample)
{
        FLAC__uint64 length;

        FLAC__ASSERT(0 != decoder);

        if(
                decoder->protected_->state != FLAC__STREAM_DECODER_SEARCH_FOR_METADATA &&
                decoder->protected_->state != FLAC__STREAM_DECODER_READ_METADATA &&
                decoder->protected_->state != FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC &&
                decoder->protected_->state != FLAC__STREAM_DECODER_READ_FRAME &&
                decoder->protected_->state != FLAC__STREAM_DECODER_END_OF_STREAM
        )
                return false;

        if(0 == decoder->private_->seek_callback)
                return false;

        FLAC__ASSERT(decoder->private_->seek_callback);
        FLAC__ASSERT(decoder->private_->tell_callback);
        FLAC__ASSERT(decoder->private_->length_callback);
        FLAC__ASSERT(decoder->private_->eof_callback);

        if(FLAC__stream_decoder_get_total_samples(decoder) > 0 && sample >= FLAC__stream_decoder_get_total_samples(decoder))
                return false;

        decoder->private_->is_seeking = true;

        /* turn off md5 checking if a seek is attempted */
        decoder->private_->do_md5_checking = false;

        /* 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) */
        if(decoder->private_->length_callback(decoder, &length, decoder->private_->client_data) != FLAC__STREAM_DECODER_LENGTH_STATUS_OK) {
                decoder->private_->is_seeking = false;
                return false;
        }

        /* if we haven't finished processing the metadata yet, do that so we have the STREAMINFO, SEEK_TABLE, and first_frame_offset */
        if(
                decoder->protected_->state == FLAC__STREAM_DECODER_SEARCH_FOR_METADATA ||
                decoder->protected_->state == FLAC__STREAM_DECODER_READ_METADATA
        ) {
                if(!FLAC__stream_decoder_process_until_end_of_metadata(decoder)) {
                        /* above call sets the state for us */
                        decoder->private_->is_seeking = false;
                        return false;
                }
                /* check this again in case we didn't know total_samples the first time */
                if(FLAC__stream_decoder_get_total_samples(decoder) > 0 && sample >= FLAC__stream_decoder_get_total_samples(decoder)) {
                        decoder->private_->is_seeking = false;
                        return false;
                }
        }

        {
                const FLAC__bool ok =
#if FLAC__HAS_OGG
                        decoder->private_->is_ogg?
                        seek_to_absolute_sample_ogg_(decoder, length, sample) :
#endif
                        seek_to_absolute_sample_(decoder, length, sample)
                ;
                decoder->private_->is_seeking = false;
                return ok;
        }
}

/***********************************************************************
 *
 * Protected class methods
 *
 ***********************************************************************/

uint32_t FLAC__stream_decoder_get_input_bytes_unconsumed(const FLAC__StreamDecoder *decoder)
{
        FLAC__ASSERT(0 != decoder);
        FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));
        FLAC__ASSERT(!(FLAC__bitreader_get_input_bits_unconsumed(decoder->private_->input) & 7));
        return FLAC__bitreader_get_input_bits_unconsumed(decoder->private_->input) / 8;
}

/***********************************************************************
 *
 * Private class methods
 *
 ***********************************************************************/

void set_defaults_(FLAC__StreamDecoder *decoder)
{
        decoder->private_->is_ogg = false;
        decoder->private_->read_callback = 0;
        decoder->private_->seek_callback = 0;
        decoder->private_->tell_callback = 0;
        decoder->private_->length_callback = 0;
        decoder->private_->eof_callback = 0;
        decoder->private_->write_callback = 0;
        decoder->private_->metadata_callback = 0;
        decoder->private_->error_callback = 0;
        decoder->private_->client_data = 0;

        memset(decoder->private_->metadata_filter, 0, sizeof(decoder->private_->metadata_filter));
        decoder->private_->metadata_filter[FLAC__METADATA_TYPE_STREAMINFO] = true;
        decoder->private_->metadata_filter_ids_count = 0;

        decoder->protected_->md5_checking = false;

#if FLAC__HAS_OGG
        FLAC__ogg_decoder_aspect_set_defaults(&decoder->protected_->ogg_decoder_aspect);
#endif
}

/*
 * This will forcibly set stdin to binary mode (for OSes that require it)
 */
FILE *get_binary_stdin_(void)
{
        /* if something breaks here it is probably due to the presence or
         * absence of an underscore before the identifiers 'setmode',
         * 'fileno', and/or 'O_BINARY'; check your system header files.
         */
#if defined _MSC_VER || defined __MINGW32__
        _setmode(_fileno(stdin), _O_BINARY);
#elif defined __EMX__
        setmode(fileno(stdin), O_BINARY);
#endif

        return stdin;
}

FLAC__bool allocate_output_(FLAC__StreamDecoder *decoder, uint32_t size, uint32_t channels)
{
        uint32_t i;
        FLAC__int32 *tmp;

        if(size <= decoder->private_->output_capacity && channels <= decoder->private_->output_channels)
                return true;

        /* simply using realloc() is not practical because the number of channels may change mid-stream */

        for(i = 0; i < FLAC__MAX_CHANNELS; i++) {
                if(0 != decoder->private_->output[i]) {
                        free(decoder->private_->output[i]-4);
                        decoder->private_->output[i] = 0;
                }
                if(0 != decoder->private_->residual_unaligned[i]) {
                        free(decoder->private_->residual_unaligned[i]);
                        decoder->private_->residual_unaligned[i] = decoder->private_->residual[i] = 0;
                }
        }

        for(i = 0; i < channels; i++) {
                /* WATCHOUT:
                 * FLAC__lpc_restore_signal_asm_ia32_mmx() and ..._intrin_sseN()
                 * require that the output arrays have a buffer of up to 3 zeroes
                 * in front (at negative indices) for alignment purposes;
                 * we use 4 to keep the data well-aligned.
                 */
                tmp = safe_malloc_muladd2_(sizeof(FLAC__int32), /*times (*/size, /*+*/4/*)*/);
                if(tmp == 0) {
                        decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
                        return false;
                }
                memset(tmp, 0, sizeof(FLAC__int32)*4);
                decoder->private_->output[i] = tmp + 4;

                if(!FLAC__memory_alloc_aligned_int32_array(size, &decoder->private_->residual_unaligned[i], &decoder->private_->residual[i])) {
                        decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
                        return false;
                }
        }

        decoder->private_->output_capacity = size;
        decoder->private_->output_channels = channels;

        return true;
}

FLAC__bool has_id_filtered_(FLAC__StreamDecoder *decoder, FLAC__byte *id)
{
        size_t i;

        FLAC__ASSERT(0 != decoder);
        FLAC__ASSERT(0 != decoder->private_);

        for(i = 0; i < decoder->private_->metadata_filter_ids_count; i++)
                if(0 == memcmp(decoder->private_->metadata_filter_ids + i * (FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8), id, (FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8)))
                        return true;

        return false;
}

FLAC__bool find_metadata_(FLAC__StreamDecoder *decoder)
{
        FLAC__uint32 x;
        uint32_t i, id;
        FLAC__bool first = true;

        FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));

        for(i = id = 0; i < 4; ) {
                if(decoder->private_->cached) {
                        x = (FLAC__uint32)decoder->private_->lookahead;
                        decoder->private_->cached = false;
                }
                else {
                        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
                                return false; /* read_callback_ sets the state for us */
                }
                if(x == FLAC__STREAM_SYNC_STRING[i]) {
                        first = true;
                        i++;
                        id = 0;
                        continue;
                }

                if(id >= 3)
                        return false;

                if(x == ID3V2_TAG_[id]) {
                        id++;
                        i = 0;
                        if(id == 3) {
                                if(!skip_id3v2_tag_(decoder))
                                        return false; /* skip_id3v2_tag_ sets the state for us */
                        }
                        continue;
                }
                id = 0;
                if(x == 0xff) { /* MAGIC NUMBER for the first 8 frame sync bits */
                        decoder->private_->header_warmup[0] = (FLAC__byte)x;
                        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
                                return false; /* read_callback_ sets the state for us */

                        /* 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 */
                        /* else we have to check if the second byte is the end of a sync code */
                        if(x == 0xff) { /* MAGIC NUMBER for the first 8 frame sync bits */
                                decoder->private_->lookahead = (FLAC__byte)x;
                                decoder->private_->cached = true;
                        }
                        else if(x >> 1 == 0x7c) { /* MAGIC NUMBER for the last 6 sync bits and reserved 7th bit */
                                decoder->private_->header_warmup[1] = (FLAC__byte)x;
                                decoder->protected_->state = FLAC__STREAM_DECODER_READ_FRAME;
                                return true;
                        }
                }
                i = 0;
                if(first) {
                        send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
                        first = false;
                }
        }

        decoder->protected_->state = FLAC__STREAM_DECODER_READ_METADATA;
        return true;
}

FLAC__bool read_metadata_(FLAC__StreamDecoder *decoder)
{
        FLAC__bool is_last;
        FLAC__uint32 i, x, type, length;

        FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));

        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_IS_LAST_LEN))
                return false; /* read_callback_ sets the state for us */
        is_last = x? true : false;

        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &type, FLAC__STREAM_METADATA_TYPE_LEN))
                return false; /* read_callback_ sets the state for us */

        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &length, FLAC__STREAM_METADATA_LENGTH_LEN))
                return false; /* read_callback_ sets the state for us */

        if(type == FLAC__METADATA_TYPE_STREAMINFO) {
                if(!read_metadata_streaminfo_(decoder, is_last, length))
                        return false;

                decoder->private_->has_stream_info = true;
                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))
                        decoder->private_->do_md5_checking = false;
                if(!decoder->private_->is_seeking && decoder->private_->metadata_filter[FLAC__METADATA_TYPE_STREAMINFO] && decoder->private_->metadata_callback)
                        decoder->private_->metadata_callback(decoder, &decoder->private_->stream_info, decoder->private_->client_data);
        }
        else if(type == FLAC__METADATA_TYPE_SEEKTABLE) {
                /* just in case we already have a seek table, and reading the next one fails: */
                decoder->private_->has_seek_table = false;

                if(!read_metadata_seektable_(decoder, is_last, length))
                        return false;

                decoder->private_->has_seek_table = true;
                if(!decoder->private_->is_seeking && decoder->private_->metadata_filter[FLAC__METADATA_TYPE_SEEKTABLE] && decoder->private_->metadata_callback)
                        decoder->private_->metadata_callback(decoder, &decoder->private_->seek_table, decoder->private_->client_data);
        }
        else {
                FLAC__bool skip_it = !decoder->private_->metadata_filter[type];
                uint32_t real_length = length;
                FLAC__StreamMetadata block;

                memset(&block, 0, sizeof(block));
                block.is_last = is_last;
                block.type = (FLAC__MetadataType)type;
                block.length = length;

                if(type == FLAC__METADATA_TYPE_APPLICATION) {
                        if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, block.data.application.id, FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8))
                                return false; /* read_callback_ sets the state for us */

                        if(real_length < FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8) { /* underflow check */
                                decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;/*@@@@@@ maybe wrong error? need to resync?*/
                                return false;
                        }

                        real_length -= FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8;

                        if(decoder->private_->metadata_filter_ids_count > 0 && has_id_filtered_(decoder, block.data.application.id))
                                skip_it = !skip_it;
                }

                if(skip_it) {
                        if(!FLAC__bitreader_skip_byte_block_aligned_no_crc(decoder->private_->input, real_length))
                                return false; /* read_callback_ sets the state for us */
                }
                else {
                        FLAC__bool ok = true;
                        switch(type) {
                                case FLAC__METADATA_TYPE_PADDING:
                                        /* skip the padding bytes */
                                        if(!FLAC__bitreader_skip_byte_block_aligned_no_crc(decoder->private_->input, real_length))
                                                ok = false; /* read_callback_ sets the state for us */
                                        break;
                                case FLAC__METADATA_TYPE_APPLICATION:
                                        /* remember, we read the ID already */
                                        if(real_length > 0) {
                                                if(0 == (block.data.application.data = malloc(real_length))) {
                                                        decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
                                                        ok = false;
                                                }
                                                else if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, block.data.application.data, real_length))
                                                        ok = false; /* read_callback_ sets the state for us */
                                        }
                                        else
                                                block.data.application.data = 0;
                                        break;
                                case FLAC__METADATA_TYPE_VORBIS_COMMENT:
                                        if(!read_metadata_vorbiscomment_(decoder, &block.data.vorbis_comment, real_length))
                                                ok = false;
                                        break;
                                case FLAC__METADATA_TYPE_CUESHEET:
                                        if(!read_metadata_cuesheet_(decoder, &block.data.cue_sheet))
                                                ok = false;
                                        break;
                                case FLAC__METADATA_TYPE_PICTURE:
                                        if(!read_metadata_picture_(decoder, &block.data.picture))
                                                ok = false;
                                        break;
                                case FLAC__METADATA_TYPE_STREAMINFO:
                                case FLAC__METADATA_TYPE_SEEKTABLE:
                                        FLAC__ASSERT(0);
                                        break;
                                default:
                                        if(real_length > 0) {
                                                if(0 == (block.data.unknown.data = malloc(real_length))) {
                                                        decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
                                                        ok = false;
                                                }
                                                else if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, block.data.unknown.data, real_length))
                                                        ok = false; /* read_callback_ sets the state for us */
                                        }
                                        else
                                                block.data.unknown.data = 0;
                                        break;
                        }
                        if(ok && !decoder->private_->is_seeking && decoder->private_->metadata_callback)
                                decoder->private_->metadata_callback(decoder, &block, decoder->private_->client_data);

                        /* now we have to free any malloc()ed data in the block */
                        switch(type) {
                                case FLAC__METADATA_TYPE_PADDING:
                                        break;
                                case FLAC__METADATA_TYPE_APPLICATION:
                                        if(0 != block.data.application.data)
                                                free(block.data.application.data);
                                        break;
                                case FLAC__METADATA_TYPE_VORBIS_COMMENT:
                                        if(0 != block.data.vorbis_comment.vendor_string.entry)
                                                free(block.data.vorbis_comment.vendor_string.entry);
                                        if(block.data.vorbis_comment.num_comments > 0)
                                                for(i = 0; i < block.data.vorbis_comment.num_comments; i++)
                                                        if(0 != block.data.vorbis_comment.comments[i].entry)
                                                                free(block.data.vorbis_comment.comments[i].entry);
                                        if(0 != block.data.vorbis_comment.comments)
                                                free(block.data.vorbis_comment.comments);
                                        break;
                                case FLAC__METADATA_TYPE_CUESHEET:
                                        if(block.data.cue_sheet.num_tracks > 0)
                                                for(i = 0; i < block.data.cue_sheet.num_tracks; i++)
                                                        if(0 != block.data.cue_sheet.tracks[i].indices)
                                                                free(block.data.cue_sheet.tracks[i].indices);
                                        if(0 != block.data.cue_sheet.tracks)
                                                free(block.data.cue_sheet.tracks);
                                        break;
                                case FLAC__METADATA_TYPE_PICTURE:
                                        if(0 != block.data.picture.mime_type)
                                                free(block.data.picture.mime_type);
                                        if(0 != block.data.picture.description)
                                                free(block.data.picture.description);
                                        if(0 != block.data.picture.data)
                                                free(block.data.picture.data);
                                        break;
                                case FLAC__METADATA_TYPE_STREAMINFO:
                                case FLAC__METADATA_TYPE_SEEKTABLE:
                                        FLAC__ASSERT(0);
                                default:
                                        if(0 != block.data.unknown.data)
                                                free(block.data.unknown.data);
                                        break;
                        }

                        if(!ok) /* anything that unsets "ok" should also make sure decoder->protected_->state is updated */
                                return false;
                }
        }

        if(is_last) {
                /* if this fails, it's OK, it's just a hint for the seek routine */
                if(!FLAC__stream_decoder_get_decode_position(decoder, &decoder->private_->first_frame_offset))
                        decoder->private_->first_frame_offset = 0;
                decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
        }

        return true;
}

FLAC__bool read_metadata_streaminfo_(FLAC__StreamDecoder *decoder, FLAC__bool is_last, uint32_t length)
{
        FLAC__uint32 x;
        uint32_t bits, used_bits = 0;

        FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));

        decoder->private_->stream_info.type = FLAC__METADATA_TYPE_STREAMINFO;
        decoder->private_->stream_info.is_last = is_last;
        decoder->private_->stream_info.length = length;

        bits = FLAC__STREAM_METADATA_STREAMINFO_MIN_BLOCK_SIZE_LEN;
        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, bits))
                return false; /* read_callback_ sets the state for us */
        decoder->private_->stream_info.data.stream_info.min_blocksize = x;
        used_bits += bits;

        bits = FLAC__STREAM_METADATA_STREAMINFO_MAX_BLOCK_SIZE_LEN;
        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_MAX_BLOCK_SIZE_LEN))
                return false; /* read_callback_ sets the state for us */
        decoder->private_->stream_info.data.stream_info.max_blocksize = x;
        used_bits += bits;

        bits = FLAC__STREAM_METADATA_STREAMINFO_MIN_FRAME_SIZE_LEN;
        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_MIN_FRAME_SIZE_LEN))
                return false; /* read_callback_ sets the state for us */
        decoder->private_->stream_info.data.stream_info.min_framesize = x;
        used_bits += bits;

        bits = FLAC__STREAM_METADATA_STREAMINFO_MAX_FRAME_SIZE_LEN;
        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_MAX_FRAME_SIZE_LEN))
                return false; /* read_callback_ sets the state for us */
        decoder->private_->stream_info.data.stream_info.max_framesize = x;
        used_bits += bits;

        bits = FLAC__STREAM_METADATA_STREAMINFO_SAMPLE_RATE_LEN;
        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_SAMPLE_RATE_LEN))
                return false; /* read_callback_ sets the state for us */
        decoder->private_->stream_info.data.stream_info.sample_rate = x;
        used_bits += bits;

        bits = FLAC__STREAM_METADATA_STREAMINFO_CHANNELS_LEN;
        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_CHANNELS_LEN))
                return false; /* read_callback_ sets the state for us */
        decoder->private_->stream_info.data.stream_info.channels = x+1;
        used_bits += bits;

        bits = FLAC__STREAM_METADATA_STREAMINFO_BITS_PER_SAMPLE_LEN;
        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_BITS_PER_SAMPLE_LEN))
                return false; /* read_callback_ sets the state for us */
        decoder->private_->stream_info.data.stream_info.bits_per_sample = x+1;
        used_bits += bits;

        bits = FLAC__STREAM_METADATA_STREAMINFO_TOTAL_SAMPLES_LEN;
        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))
                return false; /* read_callback_ sets the state for us */
        used_bits += bits;

        if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, decoder->private_->stream_info.data.stream_info.md5sum, 16))
                return false; /* read_callback_ sets the state for us */
        used_bits += 16*8;

        /* skip the rest of the block */
        FLAC__ASSERT(used_bits % 8 == 0);
        length -= (used_bits / 8);
        if(!FLAC__bitreader_skip_byte_block_aligned_no_crc(decoder->private_->input, length))
                return false; /* read_callback_ sets the state for us */

        return true;
}

FLAC__bool read_metadata_seektable_(FLAC__StreamDecoder *decoder, FLAC__bool is_last, uint32_t length)
{
        FLAC__uint32 i, x;
        FLAC__uint64 xx;

        FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));

        decoder->private_->seek_table.type = FLAC__METADATA_TYPE_SEEKTABLE;
        decoder->private_->seek_table.is_last = is_last;
        decoder->private_->seek_table.length = length;

        decoder->private_->seek_table.data.seek_table.num_points = length / FLAC__STREAM_METADATA_SEEKPOINT_LENGTH;

        /* use realloc since we may pass through here several times (e.g. after seeking) */
        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)))) {
                decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
                return false;
        }
        for(i = 0; i < decoder->private_->seek_table.data.seek_table.num_points; i++) {
                if(!FLAC__bitreader_read_raw_uint64(decoder->private_->input, &xx, FLAC__STREAM_METADATA_SEEKPOINT_SAMPLE_NUMBER_LEN))
                        return false; /* read_callback_ sets the state for us */
                decoder->private_->seek_table.data.seek_table.points[i].sample_number = xx;

                if(!FLAC__bitreader_read_raw_uint64(decoder->private_->input, &xx, FLAC__STREAM_METADATA_SEEKPOINT_STREAM_OFFSET_LEN))
                        return false; /* read_callback_ sets the state for us */
                decoder->private_->seek_table.data.seek_table.points[i].stream_offset = xx;

                if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_SEEKPOINT_FRAME_SAMPLES_LEN))
                        return false; /* read_callback_ sets the state for us */
                decoder->private_->seek_table.data.seek_table.points[i].frame_samples = x;
        }
        length -= (decoder->private_->seek_table.data.seek_table.num_points * FLAC__STREAM_METADATA_SEEKPOINT_LENGTH);
        /* if there is a partial point left, skip over it */
        if(length > 0) {
                /*@@@ do a send_error_to_client_() here?  there's an argument for either way */
                if(!FLAC__bitreader_skip_byte_block_aligned_no_crc(decoder->private_->input, length))
                        return false; /* read_callback_ sets the state for us */
        }

        return true;
}

FLAC__bool read_metadata_vorbiscomment_(FLAC__StreamDecoder *decoder, FLAC__StreamMetadata_VorbisComment *obj, uint32_t length)
{
        FLAC__uint32 i;

        FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));

        /* read vendor string */
        if (length >= 8) {
                length -= 8; /* vendor string length + num comments entries alone take 8 bytes */
                FLAC__ASSERT(FLAC__STREAM_METADATA_VORBIS_COMMENT_ENTRY_LENGTH_LEN == 32);
                if (!FLAC__bitreader_read_uint32_little_endian(decoder->private_->input, &obj->vendor_string.length))
                        return false; /* read_callback_ sets the state for us */
                if (obj->vendor_string.length > 0) {
                        if (length < obj->vendor_string.length) {
                                obj->vendor_string.length = 0;
                                obj->vendor_string.entry = 0;
                                goto skip;
                        }
                        else
                                length -= obj->vendor_string.length;
                        if (0 == (obj->vendor_string.entry = safe_malloc_add_2op_(obj->vendor_string.length, /*+*/1))) {
                                decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
                                return false;
                        }
                        if (!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, obj->vendor_string.entry, obj->vendor_string.length))
                                return false; /* read_callback_ sets the state for us */
                        obj->vendor_string.entry[obj->vendor_string.length] = '\0';
                }
                else
                        obj->vendor_string.entry = 0;

                /* read num comments */
                FLAC__ASSERT(FLAC__STREAM_METADATA_VORBIS_COMMENT_NUM_COMMENTS_LEN == 32);
                if (!FLAC__bitreader_read_uint32_little_endian(decoder->private_->input, &obj->num_comments))
                        return false; /* read_callback_ sets the state for us */

                /* read comments */
                if (obj->num_comments > 100000) {
                        /* Possibly malicious file. */
                        obj->num_comments = 0;
                        return false;
                }
                if (obj->num_comments > 0) {
                        if (0 == (obj->comments = safe_malloc_mul_2op_p(obj->num_comments, /*times*/sizeof(FLAC__StreamMetadata_VorbisComment_Entry)))) {
                                obj->num_comments = 0;
                                decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
                                return false;
                        }
                        for (i = 0; i < obj->num_comments; i++) {
                                /* Initialize here just to make sure. */
                                obj->comments[i].length = 0;
                                obj->comments[i].entry = 0;

                                FLAC__ASSERT(FLAC__STREAM_METADATA_VORBIS_COMMENT_ENTRY_LENGTH_LEN == 32);
                                if (length < 4) {
                                        obj->num_comments = i;
                                        goto skip;
                                }
                                else
                                        length -= 4;
                                if (!FLAC__bitreader_read_uint32_little_endian(decoder->private_->input, &obj->comments[i].length)) {
                                        obj->num_comments = i;
                                        return false; /* read_callback_ sets the state for us */
                                }
                                if (obj->comments[i].length > 0) {
                                        if (length < obj->comments[i].length) {
                                                obj->num_comments = i;
                                                goto skip;
                                        }
                                        else
                                                length -= obj->comments[i].length;
                                        if (0 == (obj->comments[i].entry = safe_malloc_add_2op_(obj->comments[i].length, /*+*/1))) {
                                                decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
                                                obj->num_comments = i;
                                                return false;
                                        }
                                        memset (obj->comments[i].entry, 0, obj->comments[i].length) ;
                                        if (!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, obj->comments[i].entry, obj->comments[i].length)) {
                                                /* Current i-th entry is bad, so we delete it. */
                                                free (obj->comments[i].entry) ;
                                                obj->comments[i].entry = NULL ;
                                                obj->num_comments = i;
                                                goto skip;
                                        }
                                        obj->comments[i].entry[obj->comments[i].length] = '\0';
                                }
                                else
                                        obj->comments[i].entry = 0;
                        }
                }
        }

  skip:
        if (length > 0) {
                /* length > 0 can only happen on files with invalid data in comments */
                if(obj->num_comments < 1) {
                        free(obj->comments);
                        obj->comments = NULL;
                }
                if(!FLAC__bitreader_skip_byte_block_aligned_no_crc(decoder->private_->input, length))
                        return false; /* read_callback_ sets the state for us */
        }

        return true;
}

FLAC__bool read_metadata_cuesheet_(FLAC__StreamDecoder *decoder, FLAC__StreamMetadata_CueSheet *obj)
{
        FLAC__uint32 i, j, x;

        FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));

        memset(obj, 0, sizeof(FLAC__StreamMetadata_CueSheet));

        FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_MEDIA_CATALOG_NUMBER_LEN % 8 == 0);
        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))
                return false; /* read_callback_ sets the state for us */

        if(!FLAC__bitreader_read_raw_uint64(decoder->private_->input, &obj->lead_in, FLAC__STREAM_METADATA_CUESHEET_LEAD_IN_LEN))
                return false; /* read_callback_ sets the state for us */

        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_IS_CD_LEN))
                return false; /* read_callback_ sets the state for us */
        obj->is_cd = x? true : false;

        if(!FLAC__bitreader_skip_bits_no_crc(decoder->private_->input, FLAC__STREAM_METADATA_CUESHEET_RESERVED_LEN))
                return false; /* read_callback_ sets the state for us */

        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_NUM_TRACKS_LEN))
                return false; /* read_callback_ sets the state for us */
        obj->num_tracks = x;

        if(obj->num_tracks > 0) {
                if(0 == (obj->tracks = safe_calloc_(obj->num_tracks, sizeof(FLAC__StreamMetadata_CueSheet_Track)))) {
                        decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
                        return false;
                }
                for(i = 0; i < obj->num_tracks; i++) {
                        FLAC__StreamMetadata_CueSheet_Track *track = &obj->tracks[i];
                        if(!FLAC__bitreader_read_raw_uint64(decoder->private_->input, &track->offset, FLAC__STREAM_METADATA_CUESHEET_TRACK_OFFSET_LEN))
                                return false; /* read_callback_ sets the state for us */

                        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_TRACK_NUMBER_LEN))
                                return false; /* read_callback_ sets the state for us */
                        track->number = (FLAC__byte)x;

                        FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_TRACK_ISRC_LEN % 8 == 0);
                        if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, (FLAC__byte*)track->isrc, FLAC__STREAM_METADATA_CUESHEET_TRACK_ISRC_LEN/8))
                                return false; /* read_callback_ sets the state for us */

                        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_TRACK_TYPE_LEN))
                                return false; /* read_callback_ sets the state for us */
                        track->type = x;

                        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_TRACK_PRE_EMPHASIS_LEN))
                                return false; /* read_callback_ sets the state for us */
                        track->pre_emphasis = x;

                        if(!FLAC__bitreader_skip_bits_no_crc(decoder->private_->input, FLAC__STREAM_METADATA_CUESHEET_TRACK_RESERVED_LEN))
                                return false; /* read_callback_ sets the state for us */

                        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_TRACK_NUM_INDICES_LEN))
                                return false; /* read_callback_ sets the state for us */
                        track->num_indices = (FLAC__byte)x;

                        if(track->num_indices > 0) {
                                if(0 == (track->indices = safe_calloc_(track->num_indices, sizeof(FLAC__StreamMetadata_CueSheet_Index)))) {
                                        decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
                                        return false;
                                }
                                for(j = 0; j < track->num_indices; j++) {
                                        FLAC__StreamMetadata_CueSheet_Index *indx = &track->indices[j];
                                        if(!FLAC__bitreader_read_raw_uint64(decoder->private_->input, &indx->offset, FLAC__STREAM_METADATA_CUESHEET_INDEX_OFFSET_LEN))
                                                return false; /* read_callback_ sets the state for us */

                                        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_INDEX_NUMBER_LEN))
                                                return false; /* read_callback_ sets the state for us */
                                        indx->number = (FLAC__byte)x;

                                        if(!FLAC__bitreader_skip_bits_no_crc(decoder->private_->input, FLAC__STREAM_METADATA_CUESHEET_INDEX_RESERVED_LEN))
                                                return false; /* read_callback_ sets the state for us */
                                }
                        }
                }
        }

        return true;
}

FLAC__bool read_metadata_picture_(FLAC__StreamDecoder *decoder, FLAC__StreamMetadata_Picture *obj)
{
        FLAC__uint32 x;

        FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));

        /* read type */
        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_PICTURE_TYPE_LEN))
                return false; /* read_callback_ sets the state for us */
        obj->type = x;

        /* read MIME type */
        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_PICTURE_MIME_TYPE_LENGTH_LEN))
                return false; /* read_callback_ sets the state for us */
        if(0 == (obj->mime_type = safe_malloc_add_2op_(x, /*+*/1))) {
                decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
                return false;
        }
        if(x > 0) {
                if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, (FLAC__byte*)obj->mime_type, x))
                        return false; /* read_callback_ sets the state for us */
        }
        obj->mime_type[x] = '\0';

        /* read description */
        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_PICTURE_DESCRIPTION_LENGTH_LEN))
                return false; /* read_callback_ sets the state for us */
        if(0 == (obj->description = safe_malloc_add_2op_(x, /*+*/1))) {
                decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
                return false;
        }
        if(x > 0) {
                if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, obj->description, x))
                        return false; /* read_callback_ sets the state for us */
        }
        obj->description[x] = '\0';

        /* read width */
        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &obj->width, FLAC__STREAM_METADATA_PICTURE_WIDTH_LEN))
                return false; /* read_callback_ sets the state for us */

        /* read height */
        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &obj->height, FLAC__STREAM_METADATA_PICTURE_HEIGHT_LEN))
                return false; /* read_callback_ sets the state for us */

        /* read depth */
        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &obj->depth, FLAC__STREAM_METADATA_PICTURE_DEPTH_LEN))
                return false; /* read_callback_ sets the state for us */

        /* read colors */
        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &obj->colors, FLAC__STREAM_METADATA_PICTURE_COLORS_LEN))
                return false; /* read_callback_ sets the state for us */

        /* read data */
        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &(obj->data_length), FLAC__STREAM_METADATA_PICTURE_DATA_LENGTH_LEN))
                return false; /* read_callback_ sets the state for us */
        if(0 == (obj->data = safe_malloc_(obj->data_length))) {
                decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
                return false;
        }
        if(obj->data_length > 0) {
                if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, obj->data, obj->data_length))
                        return false; /* read_callback_ sets the state for us */
        }

        return true;
}

FLAC__bool skip_id3v2_tag_(FLAC__StreamDecoder *decoder)
{
        FLAC__uint32 x;
        uint32_t i, skip;

        /* skip the version and flags bytes */
        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 24))
                return false; /* read_callback_ sets the state for us */
        /* get the size (in bytes) to skip */
        skip = 0;
        for(i = 0; i < 4; i++) {
                if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
                        return false; /* read_callback_ sets the state for us */
                skip <<= 7;
                skip |= (x & 0x7f);
        }
        /* skip the rest of the tag */
        if(!FLAC__bitreader_skip_byte_block_aligned_no_crc(decoder->private_->input, skip))
                return false; /* read_callback_ sets the state for us */
        return true;
}

FLAC__bool frame_sync_(FLAC__StreamDecoder *decoder)
{
        FLAC__uint32 x;
        FLAC__bool first = true;

        /* If we know the total number of samples in the stream, stop if we've read that many. */
        /* This will stop us, for example, from wasting time trying to sync on an ID3V1 tag. */
        if(FLAC__stream_decoder_get_total_samples(decoder) > 0) {
                if(decoder->private_->samples_decoded >= FLAC__stream_decoder_get_total_samples(decoder)) {
                        decoder->protected_->state = FLAC__STREAM_DECODER_END_OF_STREAM;
                        return true;
                }
        }

        /* make sure we're byte aligned */
        if(!FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input)) {
                if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__bitreader_bits_left_for_byte_alignment(decoder->private_->input)))
                        return false; /* read_callback_ sets the state for us */
        }

        while(1) {
                if(decoder->private_->cached) {
                        x = (FLAC__uint32)decoder->private_->lookahead;
                        decoder->private_->cached = false;
                }
                else {
                        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
                                return false; /* read_callback_ sets the state for us */
                }
                if(x == 0xff) { /* MAGIC NUMBER for the first 8 frame sync bits */
                        decoder->private_->header_warmup[0] = (FLAC__byte)x;
                        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
                                return false; /* read_callback_ sets the state for us */

                        /* 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 */
                        /* else we have to check if the second byte is the end of a sync code */
                        if(x == 0xff) { /* MAGIC NUMBER for the first 8 frame sync bits */
                                decoder->private_->lookahead = (FLAC__byte)x;
                                decoder->private_->cached = true;
                        }
                        else if(x >> 1 == 0x7c) { /* MAGIC NUMBER for the last 6 sync bits and reserved 7th bit */
                                decoder->private_->header_warmup[1] = (FLAC__byte)x;
                                decoder->protected_->state = FLAC__STREAM_DECODER_READ_FRAME;
                                return true;
                        }
                }
                if(first) {
                        send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
                        first = false;
                }
        }

        return true;
}

FLAC__bool read_frame_(FLAC__StreamDecoder *decoder, FLAC__bool *got_a_frame, FLAC__bool do_full_decode)
{
        uint32_t channel;
        uint32_t i;
        FLAC__int32 mid, side;
        uint32_t frame_crc; /* the one we calculate from the input stream */
        FLAC__uint32 x;

        *got_a_frame = false;

        /* init the CRC */
        frame_crc = 0;
        frame_crc = FLAC__CRC16_UPDATE(decoder->private_->header_warmup[0], frame_crc);
        frame_crc = FLAC__CRC16_UPDATE(decoder->private_->header_warmup[1], frame_crc);
        FLAC__bitreader_reset_read_crc16(decoder->private_->input, (FLAC__uint16)frame_crc);

        if(!read_frame_header_(decoder))
                return false;
        if(decoder->protected_->state == FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC) /* means we didn't sync on a valid header */
                return true;
        if(!allocate_output_(decoder, decoder->private_->frame.header.blocksize, decoder->private_->frame.header.channels))
                return false;
        for(channel = 0; channel < decoder->private_->frame.header.channels; channel++) {
                /*
                 * first figure the correct bits-per-sample of the subframe
                 */
                uint32_t bps = decoder->private_->frame.header.bits_per_sample;
                switch(decoder->private_->frame.header.channel_assignment) {
                        case FLAC__CHANNEL_ASSIGNMENT_INDEPENDENT:
                                /* no adjustment needed */
                                break;
                        case FLAC__CHANNEL_ASSIGNMENT_LEFT_SIDE:
                                FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
                                if(channel == 1)
                                        bps++;
                                break;
                        case FLAC__CHANNEL_ASSIGNMENT_RIGHT_SIDE:
                                FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
                                if(channel == 0)
                                        bps++;
                                break;
                        case FLAC__CHANNEL_ASSIGNMENT_MID_SIDE:
                                FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
                                if(channel == 1)
                                        bps++;
                                break;
                        default:
                                FLAC__ASSERT(0);
                }
                /*
                 * now read it
                 */
                if(!read_subframe_(decoder, channel, bps, do_full_decode))
                        return false;
                if(decoder->protected_->state == FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC) /* means bad sync or got corruption */
                        return true;
        }
        if(!read_zero_padding_(decoder))
                return false;
        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) */
                return true;

        /*
         * Read the frame CRC-16 from the footer and check
         */
        frame_crc = FLAC__bitreader_get_read_crc16(decoder->private_->input);
        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__FRAME_FOOTER_CRC_LEN))
                return false; /* read_callback_ sets the state for us */
        if(frame_crc == x) {
                if(do_full_decode) {
                        /* Undo any special channel coding */
                        switch(decoder->private_->frame.header.channel_assignment) {
                                case FLAC__CHANNEL_ASSIGNMENT_INDEPENDENT:
                                        /* do nothing */
                                        break;
                                case FLAC__CHANNEL_ASSIGNMENT_LEFT_SIDE:
                                        FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
                                        for(i = 0; i < decoder->private_->frame.header.blocksize; i++)
                                                decoder->private_->output[1][i] = decoder->private_->output[0][i] - decoder->private_->output[1][i];
                                        break;
                                case FLAC__CHANNEL_ASSIGNMENT_RIGHT_SIDE:
                                        FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
                                        for(i = 0; i < decoder->private_->frame.header.blocksize; i++)
                                                decoder->private_->output[0][i] += decoder->private_->output[1][i];
                                        break;
                                case FLAC__CHANNEL_ASSIGNMENT_MID_SIDE:
                                        FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
                                        for(i = 0; i < decoder->private_->frame.header.blocksize; i++) {
#if 1
                                                mid = decoder->private_->output[0][i];
                                                side = decoder->private_->output[1][i];
                                                mid = ((uint32_t) mid) << 1;
                                                mid |= (side & 1); /* i.e. if 'side' is odd... */
                                                decoder->private_->output[0][i] = (mid + side) >> 1;
                                                decoder->private_->output[1][i] = (mid - side) >> 1;
#else
                                                /* OPT: without 'side' temp variable */
                                                mid = (decoder->private_->output[0][i] << 1) | (decoder->private_->output[1][i] & 1); /* i.e. if 'side' is odd... */
                                                decoder->private_->output[0][i] = (mid + decoder->private_->output[1][i]) >> 1;
                                                decoder->private_->output[1][i] = (mid - decoder->private_->output[1][i]) >> 1;
#endif
                                        }
                                        break;
                                default:
                                        FLAC__ASSERT(0);
                                        break;
                        }
                }
        }
        else {
                /* Bad frame, emit error and zero the output signal */
                send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_FRAME_CRC_MISMATCH);
                if(do_full_decode) {
                        for(channel = 0; channel < decoder->private_->frame.header.channels; channel++) {
                                memset(decoder->private_->output[channel], 0, sizeof(FLAC__int32) * decoder->private_->frame.header.blocksize);
                        }
                }
        }

        *got_a_frame = true;

        /* we wait to update fixed_block_size until here, when we're sure we've got a proper frame and hence a correct blocksize */
        if(decoder->private_->next_fixed_block_size)
                decoder->private_->fixed_block_size = decoder->private_->next_fixed_block_size;

        /* put the latest values into the public section of the decoder instance */
        decoder->protected_->channels = decoder->private_->frame.header.channels;
        decoder->protected_->channel_assignment = decoder->private_->frame.header.channel_assignment;
        decoder->protected_->bits_per_sample = decoder->private_->frame.header.bits_per_sample;
        decoder->protected_->sample_rate = decoder->private_->frame.header.sample_rate;
        decoder->protected_->blocksize = decoder->private_->frame.header.blocksize;

        FLAC__ASSERT(decoder->private_->frame.header.number_type == FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER);
        decoder->private_->samples_decoded = decoder->private_->frame.header.number.sample_number + decoder->private_->frame.header.blocksize;

        /* write it */
        if(do_full_decode) {
                if(write_audio_frame_to_client_(decoder, &decoder->private_->frame, (const FLAC__int32 * const *)decoder->private_->output) != FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE) {
                        decoder->protected_->state = FLAC__STREAM_DECODER_ABORTED;
                        return false;
                }
        }

        decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
        return true;
}

FLAC__bool read_frame_header_(FLAC__StreamDecoder *decoder)
{
        FLAC__uint32 x;
        FLAC__uint64 xx;
        uint32_t i, blocksize_hint = 0, sample_rate_hint = 0;
        FLAC__byte crc8, raw_header[16]; /* MAGIC NUMBER based on the maximum frame header size, including CRC */
        uint32_t raw_header_len;
        FLAC__bool is_unparseable = false;

        FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));

        /* init the raw header with the saved bits from synchronization */
        raw_header[0] = decoder->private_->header_warmup[0];
        raw_header[1] = decoder->private_->header_warmup[1];
        raw_header_len = 2;

        /* check to make sure that reserved bit is 0 */
        if(raw_header[1] & 0x02) /* MAGIC NUMBER */
                is_unparseable = true;

        /*
         * Note that along the way as we read the header, we look for a sync
         * code inside.  If we find one it would indicate that our original
         * sync was bad since there cannot be a sync code in a valid header.
         *
         * Three kinds of things can go wrong when reading the frame header:
         *  1) We may have sync'ed incorrectly and not landed on a frame header.
         *     If we don't find a sync code, it can end up looking like we read
         *     a valid but unparseable header, until getting to the frame header
         *     CRC.  Even then we could get a false positive on the CRC.
         *  2) We may have sync'ed correctly but on an unparseable frame (from a
         *     future encoder).
         *  3) We may be on a damaged frame which appears valid but unparseable.
         *
         * For all these reasons, we try and read a complete frame header as
         * long as it seems valid, even if unparseable, up until the frame
         * header CRC.
         */

        /*
         * read in the raw header as bytes so we can CRC it, and parse it on the way
         */
        for(i = 0; i < 2; i++) {
                if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
                        return false; /* read_callback_ sets the state for us */
                if(x == 0xff) { /* MAGIC NUMBER for the first 8 frame sync bits */
                        /* if we get here it means our original sync was erroneous since the sync code cannot appear in the header */
                        decoder->private_->lookahead = (FLAC__byte)x;
                        decoder->private_->cached = true;
                        send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER);
                        decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
                        return true;
                }
                raw_header[raw_header_len++] = (FLAC__byte)x;
        }

        switch(x = raw_header[2] >> 4) {
                case 0:
                        is_unparseable = true;
                        break;
                case 1:
                        decoder->private_->frame.header.blocksize = 192;
                        break;
                case 2:
                case 3:
                case 4:
                case 5:
                        decoder->private_->frame.header.blocksize = 576 << (x-2);
                        break;
                case 6:
                case 7:
                        blocksize_hint = x;
                        break;
                case 8:
                case 9:
                case 10:
                case 11:
                case 12:
                case 13:
                case 14:
                case 15:
                        decoder->private_->frame.header.blocksize = 256 << (x-8);
                        break;
                default:
                        FLAC__ASSERT(0);
                        break;
        }

        switch(x = raw_header[2] & 0x0f) {
                case 0:
                        if(decoder->private_->has_stream_info)
                                decoder->private_->frame.header.sample_rate = decoder->private_->stream_info.data.stream_info.sample_rate;
                        else
                                is_unparseable = true;
                        break;
                case 1:
                        decoder->private_->frame.header.sample_rate = 88200;
                        break;
                case 2:
                        decoder->private_->frame.header.sample_rate = 176400;
                        break;
                case 3:
                        decoder->private_->frame.header.sample_rate = 192000;
                        break;
                case 4:
                        decoder->private_->frame.header.sample_rate = 8000;
                        break;
                case 5:
                        decoder->private_->frame.header.sample_rate = 16000;
                        break;
                case 6:
                        decoder->private_->frame.header.sample_rate = 22050;
                        break;
                case 7:
                        decoder->private_->frame.header.sample_rate = 24000;
                        break;
                case 8:
                        decoder->private_->frame.header.sample_rate = 32000;
                        break;
                case 9:
                        decoder->private_->frame.header.sample_rate = 44100;
                        break;
                case 10:
                        decoder->private_->frame.header.sample_rate = 48000;
                        break;
                case 11:
                        decoder->private_->frame.header.sample_rate = 96000;
                        break;
                case 12:
                case 13:
                case 14:
                        sample_rate_hint = x;
                        break;
                case 15:
                        send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER);
                        decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
                        return true;
                default:
                        FLAC__ASSERT(0);
        }

        x = (uint32_t)(raw_header[3] >> 4);
        if(x & 8) {
                decoder->private_->frame.header.channels = 2;
                switch(x & 7) {
                        case 0:
                                decoder->private_->frame.header.channel_assignment = FLAC__CHANNEL_ASSIGNMENT_LEFT_SIDE;
                                break;
                        case 1:
                                decoder->private_->frame.header.channel_assignment = FLAC__CHANNEL_ASSIGNMENT_RIGHT_SIDE;
                                break;
                        case 2:
                                decoder->private_->frame.header.channel_assignment = FLAC__CHANNEL_ASSIGNMENT_MID_SIDE;
                                break;
                        default:
                                is_unparseable = true;
                                break;
                }
        }
        else {
                decoder->private_->frame.header.channels = (uint32_t)x + 1;
                decoder->private_->frame.header.channel_assignment = FLAC__CHANNEL_ASSIGNMENT_INDEPENDENT;
        }

        switch(x = (uint32_t)(raw_header[3] & 0x0e) >> 1) {
                case 0:
                        if(decoder->private_->has_stream_info)
                                decoder->private_->frame.header.bits_per_sample = decoder->private_->stream_info.data.stream_info.bits_per_sample;
                        else
                                is_unparseable = true;
                        break;
                case 1:
                        decoder->private_->frame.header.bits_per_sample = 8;
                        break;
                case 2:
                        decoder->private_->frame.header.bits_per_sample = 12;
                        break;
                case 4:
                        decoder->private_->frame.header.bits_per_sample = 16;
                        break;
                case 5:
                        decoder->private_->frame.header.bits_per_sample = 20;
                        break;
                case 6:
                        decoder->private_->frame.header.bits_per_sample = 24;
                        break;
                case 3:
                case 7:
                        is_unparseable = true;
                        break;
                default:
                        FLAC__ASSERT(0);
                        break;
        }

        /* check to make sure that reserved bit is 0 */
        if(raw_header[3] & 0x01) /* MAGIC NUMBER */
                is_unparseable = true;

        /* read the frame's starting sample number (or frame number as the case may be) */
        if(
                raw_header[1] & 0x01 ||
                /*@@@ 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 */
                (decoder->private_->has_stream_info && decoder->private_->stream_info.data.stream_info.min_blocksize != decoder->private_->stream_info.data.stream_info.max_blocksize)
        ) { /* variable blocksize */
                if(!FLAC__bitreader_read_utf8_uint64(decoder->private_->input, &xx, raw_header, &raw_header_len))
                        return false; /* read_callback_ sets the state for us */
                if(xx == FLAC__U64L(0xffffffffffffffff)) { /* i.e. non-UTF8 code... */
                        decoder->private_->lookahead = raw_header[raw_header_len-1]; /* back up as much as we can */
                        decoder->private_->cached = true;
                        send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER);
                        decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
                        return true;
                }
                decoder->private_->frame.header.number_type = FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER;
                decoder->private_->frame.header.number.sample_number = xx;
        }
        else { /* fixed blocksize */
                if(!FLAC__bitreader_read_utf8_uint32(decoder->private_->input, &x, raw_header, &raw_header_len))
                        return false; /* read_callback_ sets the state for us */
                if(x == 0xffffffff) { /* i.e. non-UTF8 code... */
                        decoder->private_->lookahead = raw_header[raw_header_len-1]; /* back up as much as we can */
                        decoder->private_->cached = true;
                        send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER);
                        decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
                        return true;
                }
                decoder->private_->frame.header.number_type = FLAC__FRAME_NUMBER_TYPE_FRAME_NUMBER;
                decoder->private_->frame.header.number.frame_number = x;
        }

        if(blocksize_hint) {
                if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
                        return false; /* read_callback_ sets the state for us */
                raw_header[raw_header_len++] = (FLAC__byte)x;
                if(blocksize_hint == 7) {
                        FLAC__uint32 _x;
                        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &_x, 8))
                                return false; /* read_callback_ sets the state for us */
                        raw_header[raw_header_len++] = (FLAC__byte)_x;
                        x = (x << 8) | _x;
                }
                decoder->private_->frame.header.blocksize = x+1;
        }

        if(sample_rate_hint) {
                if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
                        return false; /* read_callback_ sets the state for us */
                raw_header[raw_header_len++] = (FLAC__byte)x;
                if(sample_rate_hint != 12) {
                        FLAC__uint32 _x;
                        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &_x, 8))
                                return false; /* read_callback_ sets the state for us */
                        raw_header[raw_header_len++] = (FLAC__byte)_x;
                        x = (x << 8) | _x;
                }
                if(sample_rate_hint == 12)
                        decoder->private_->frame.header.sample_rate = x*1000;
                else if(sample_rate_hint == 13)
                        decoder->private_->frame.header.sample_rate = x;
                else
                        decoder->private_->frame.header.sample_rate = x*10;
        }

        /* read the CRC-8 byte */
        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
                return false; /* read_callback_ sets the state for us */
        crc8 = (FLAC__byte)x;

        if(FLAC__crc8(raw_header, raw_header_len) != crc8) {
                send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER);
                decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
                return true;
        }

        /* calculate the sample number from the frame number if needed */
        decoder->private_->next_fixed_block_size = 0;
        if(decoder->private_->frame.header.number_type == FLAC__FRAME_NUMBER_TYPE_FRAME_NUMBER) {
                x = decoder->private_->frame.header.number.frame_number;
                decoder->private_->frame.header.number_type = FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER;
                if(decoder->private_->fixed_block_size)
                        decoder->private_->frame.header.number.sample_number = (FLAC__uint64)decoder->private_->fixed_block_size * (FLAC__uint64)x;
                else if(decoder->private_->has_stream_info) {
                        if(decoder->private_->stream_info.data.stream_info.min_blocksize == decoder->private_->stream_info.data.stream_info.max_blocksize) {
                                decoder->private_->frame.header.number.sample_number = (FLAC__uint64)decoder->private_->stream_info.data.stream_info.min_blocksize * (FLAC__uint64)x;
                                decoder->private_->next_fixed_block_size = decoder->private_->stream_info.data.stream_info.max_blocksize;
                        }
                        else
                                is_unparseable = true;
                }
                else if(x == 0) {
                        decoder->private_->frame.header.number.sample_number = 0;
                        decoder->private_->next_fixed_block_size = decoder->private_->frame.header.blocksize;
                }
                else {
                        /* can only get here if the stream has invalid frame numbering and no STREAMINFO, so assume it's not the last (possibly short) frame */
                        decoder->private_->frame.header.number.sample_number = (FLAC__uint64)decoder->private_->frame.header.blocksize * (FLAC__uint64)x;
                }
        }

        if(is_unparseable) {
                send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM);
                decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
                return true;
        }

        return true;
}

FLAC__bool read_subframe_(FLAC__StreamDecoder *decoder, uint32_t channel, uint32_t bps, FLAC__bool do_full_decode)
{
        FLAC__uint32 x;
        FLAC__bool wasted_bits;
        uint32_t i;

        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8)) /* MAGIC NUMBER */
                return false; /* read_callback_ sets the state for us */

        wasted_bits = (x & 1);
        x &= 0xfe;

        if(wasted_bits) {
                uint32_t u;
                if(!FLAC__bitreader_read_unary_unsigned(decoder->private_->input, &u))
                        return false; /* read_callback_ sets the state for us */
                decoder->private_->frame.subframes[channel].wasted_bits = u+1;
                if (decoder->private_->frame.subframes[channel].wasted_bits >= bps)
                        return false;
                bps -= decoder->private_->frame.subframes[channel].wasted_bits;
        }
        else
                decoder->private_->frame.subframes[channel].wasted_bits = 0;

        /*
         * Lots of magic numbers here
         */
        if(x & 0x80) {
                send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
                decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
                return true;
        }
        else if(x == 0) {
                if(!read_subframe_constant_(decoder, channel, bps, do_full_decode))
                        return false;
        }
        else if(x == 2) {
                if(!read_subframe_verbatim_(decoder, channel, bps, do_full_decode))
                        return false;
        }
        else if(x < 16) {
                send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM);
                decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
                return true;
        }
        else if(x <= 24) {
                if(!read_subframe_fixed_(decoder, channel, bps, (x>>1)&7, do_full_decode))
                        return false;
                if(decoder->protected_->state == FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC) /* means bad sync or got corruption */
                        return true;
        }
        else if(x < 64) {
                send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM);
                decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
                return true;
        }
        else {
                if(!read_subframe_lpc_(decoder, channel, bps, ((x>>1)&31)+1, do_full_decode))
                        return false;
                if(decoder->protected_->state == FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC) /* means bad sync or got corruption */
                        return true;
        }

        if(wasted_bits && do_full_decode) {
                x = decoder->private_->frame.subframes[channel].wasted_bits;
                for(i = 0; i < decoder->private_->frame.header.blocksize; i++) {
                        uint32_t val = decoder->private_->output[channel][i];
                        decoder->private_->output[channel][i] = (val << x);
                }
        }

        return true;
}

FLAC__bool read_subframe_constant_(FLAC__StreamDecoder *decoder, uint32_t channel, uint32_t bps, FLAC__bool do_full_decode)
{
        FLAC__Subframe_Constant *subframe = &decoder->private_->frame.subframes[channel].data.constant;
        FLAC__int32 x;
        uint32_t i;
        FLAC__int32 *output = decoder->private_->output[channel];

        decoder->private_->frame.subframes[channel].type = FLAC__SUBFRAME_TYPE_CONSTANT;

        if(!FLAC__bitreader_read_raw_int32(decoder->private_->input, &x, bps))
                return false; /* read_callback_ sets the state for us */

        subframe->value = x;

        /* decode the subframe */
        if(do_full_decode) {
                for(i = 0; i < decoder->private_->frame.header.blocksize; i++)
                        output[i] = x;
        }

        return true;
}

FLAC__bool read_subframe_fixed_(FLAC__StreamDecoder *decoder, uint32_t channel, uint32_t bps, const uint32_t order, FLAC__bool do_full_decode)
{
        FLAC__Subframe_Fixed *subframe = &decoder->private_->frame.subframes[channel].data.fixed;
        FLAC__int32 i32;
        FLAC__uint32 u32;
        uint32_t u;

        decoder->private_->frame.subframes[channel].type = FLAC__SUBFRAME_TYPE_FIXED;

        subframe->residual = decoder->private_->residual[channel];
        subframe->order = order;

        /* read warm-up samples */
        for(u = 0; u < order; u++) {
                if(!FLAC__bitreader_read_raw_int32(decoder->private_->input, &i32, bps))
                        return false; /* read_callback_ sets the state for us */
                subframe->warmup[u] = i32;
        }

        /* read entropy coding method info */
        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &u32, FLAC__ENTROPY_CODING_METHOD_TYPE_LEN))
                return false; /* read_callback_ sets the state for us */
        subframe->entropy_coding_method.type = (FLAC__EntropyCodingMethodType)u32;
        switch(subframe->entropy_coding_method.type) {
                case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE:
                case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2:
                        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &u32, FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_ORDER_LEN))
                                return false; /* read_callback_ sets the state for us */
                        if(decoder->private_->frame.header.blocksize >> u32 < order) {
                                send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
                                decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
                                return true;
                        }
                        subframe->entropy_coding_method.data.partitioned_rice.order = u32;
                        subframe->entropy_coding_method.data.partitioned_rice.contents = &decoder->private_->partitioned_rice_contents[channel];
                        break;
                default:
                        send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM);
                        decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
                        return true;
        }

        /* read residual */
        switch(subframe->entropy_coding_method.type) {
                case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE:
                case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2:
                        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))
                                return false;
                        break;
                default:
                        FLAC__ASSERT(0);
        }

        /* decode the subframe */
        if(do_full_decode) {
                memcpy(decoder->private_->output[channel], subframe->warmup, sizeof(FLAC__int32) * order);
                FLAC__fixed_restore_signal(decoder->private_->residual[channel], decoder->private_->frame.header.blocksize-order, order, decoder->private_->output[channel]+order);
        }

        return true;
}

FLAC__bool read_subframe_lpc_(FLAC__StreamDecoder *decoder, uint32_t channel, uint32_t bps, const uint32_t order, FLAC__bool do_full_decode)
{
        FLAC__Subframe_LPC *subframe = &decoder->private_->frame.subframes[channel].data.lpc;
        FLAC__int32 i32;
        FLAC__uint32 u32;
        uint32_t u;

        decoder->private_->frame.subframes[channel].type = FLAC__SUBFRAME_TYPE_LPC;

        subframe->residual = decoder->private_->residual[channel];
        subframe->order = order;

        /* read warm-up samples */
        for(u = 0; u < order; u++) {
                if(!FLAC__bitreader_read_raw_int32(decoder->private_->input, &i32, bps))
                        return false; /* read_callback_ sets the state for us */
                subframe->warmup[u] = i32;
        }

        /* read qlp coeff precision */
        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &u32, FLAC__SUBFRAME_LPC_QLP_COEFF_PRECISION_LEN))
                return false; /* read_callback_ sets the state for us */
        if(u32 == (1u << FLAC__SUBFRAME_LPC_QLP_COEFF_PRECISION_LEN) - 1) {
                send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
                decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
                return true;
        }
        subframe->qlp_coeff_precision = u32+1;

        /* read qlp shift */
        if(!FLAC__bitreader_read_raw_int32(decoder->private_->input, &i32, FLAC__SUBFRAME_LPC_QLP_SHIFT_LEN))
                return false; /* read_callback_ sets the state for us */
        if(i32 < 0) {
                send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
                decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
                return true;
        }
        subframe->quantization_level = i32;

        /* read quantized lp coefficiencts */
        for(u = 0; u < order; u++) {
                if(!FLAC__bitreader_read_raw_int32(decoder->private_->input, &i32, subframe->qlp_coeff_precision))
                        return false; /* read_callback_ sets the state for us */
                subframe->qlp_coeff[u] = i32;
        }

        /* read entropy coding method info */
        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &u32, FLAC__ENTROPY_CODING_METHOD_TYPE_LEN))
                return false; /* read_callback_ sets the state for us */
        subframe->entropy_coding_method.type = (FLAC__EntropyCodingMethodType)u32;
        switch(subframe->entropy_coding_method.type) {
                case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE:
                case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2:
                        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &u32, FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_ORDER_LEN))
                                return false; /* read_callback_ sets the state for us */
                        if(decoder->private_->frame.header.blocksize >> u32 < order) {
                                send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
                                decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
                                return true;
                        }
                        subframe->entropy_coding_method.data.partitioned_rice.order = u32;
                        subframe->entropy_coding_method.data.partitioned_rice.contents = &decoder->private_->partitioned_rice_contents[channel];
                        break;
                default:
                        send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM);
                        decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
                        return true;
        }

        /* read residual */
        switch(subframe->entropy_coding_method.type) {
                case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE:
                case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2:
                        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))
                                return false;
                        break;
                default:
                        FLAC__ASSERT(0);
        }

        /* decode the subframe */
        if(do_full_decode) {
                memcpy(decoder->private_->output[channel], subframe->warmup, sizeof(FLAC__int32) * order);
                if(bps + subframe->qlp_coeff_precision + FLAC__bitmath_ilog2(order) <= 32)
                        if(bps <= 16 && subframe->qlp_coeff_precision <= 16)
                                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);
                        else
                                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);
                else
                        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);
        }

        return true;
}

FLAC__bool read_subframe_verbatim_(FLAC__StreamDecoder *decoder, uint32_t channel, uint32_t bps, FLAC__bool do_full_decode)
{
        FLAC__Subframe_Verbatim *subframe = &decoder->private_->frame.subframes[channel].data.verbatim;
        FLAC__int32 x, *residual = decoder->private_->residual[channel];
        uint32_t i;

        decoder->private_->frame.subframes[channel].type = FLAC__SUBFRAME_TYPE_VERBATIM;

        subframe->data = residual;

        for(i = 0; i < decoder->private_->frame.header.blocksize; i++) {
                if(!FLAC__bitreader_read_raw_int32(decoder->private_->input, &x, bps))
                        return false; /* read_callback_ sets the state for us */
                residual[i] = x;
        }

        /* decode the subframe */
        if(do_full_decode)
                memcpy(decoder->private_->output[channel], subframe->data, sizeof(FLAC__int32) * decoder->private_->frame.header.blocksize);

        return true;
}

FLAC__bool read_residual_partitioned_rice_(FLAC__StreamDecoder *decoder, uint32_t predictor_order, uint32_t partition_order, FLAC__EntropyCodingMethod_PartitionedRiceContents *partitioned_rice_contents, FLAC__int32 *residual, FLAC__bool is_extended)
{
        FLAC__uint32 rice_parameter;
        int i;
        uint32_t partition, sample, u;
        const uint32_t partitions = 1u << partition_order;
        const uint32_t partition_samples = partition_order > 0? decoder->private_->frame.header.blocksize >> partition_order : decoder->private_->frame.header.blocksize - predictor_order;
        const uint32_t plen = is_extended? FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2_PARAMETER_LEN : FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_PARAMETER_LEN;
        const uint32_t pesc = is_extended? FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2_ESCAPE_PARAMETER : FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_ESCAPE_PARAMETER;

        /* invalid predictor and partition orders mush be handled in the callers */
        FLAC__ASSERT(partition_order > 0? partition_samples >= predictor_order : decoder->private_->frame.header.blocksize >= predictor_order);

        if(!FLAC__format_entropy_coding_method_partitioned_rice_contents_ensure_size(partitioned_rice_contents, flac_max(6u, partition_order))) {
                decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
                return false;
        }

        sample = 0;
        for(partition = 0; partition < partitions; partition++) {
                if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &rice_parameter, plen))
                        return false; /* read_callback_ sets the state for us */
                partitioned_rice_contents->parameters[partition] = rice_parameter;
                if(rice_parameter < pesc) {
                        partitioned_rice_contents->raw_bits[partition] = 0;
                        u = (partition_order == 0 || partition > 0)? partition_samples : partition_samples - predictor_order;
                        if(!FLAC__bitreader_read_rice_signed_block(decoder->private_->input, residual + sample, u, rice_parameter))
                                return false; /* read_callback_ sets the state for us */
                        sample += u;
                }
                else {
                        if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &rice_parameter, FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_RAW_LEN))
                                return false; /* read_callback_ sets the state for us */
                        partitioned_rice_contents->raw_bits[partition] = rice_parameter;
                        for(u = (partition_order == 0 || partition > 0)? 0 : predictor_order; u < partition_samples; u++, sample++) {
                                if(!FLAC__bitreader_read_raw_int32(decoder->private_->input, &i, rice_parameter))
                                        return false; /* read_callback_ sets the state for us */
                                residual[sample] = i;
                        }
                }
        }

        return true;
}

FLAC__bool read_zero_padding_(FLAC__StreamDecoder *decoder)
{
        if(!FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input)) {
                FLAC__uint32 zero = 0;
                if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &zero, FLAC__bitreader_bits_left_for_byte_alignment(decoder->private_->input)))
                        return false; /* read_callback_ sets the state for us */
                if(zero != 0) {
                        send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
                        decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
                }
        }
        return true;
}

FLAC__bool read_callback_(FLAC__byte buffer[], size_t *bytes, void *client_data)
{
        FLAC__StreamDecoder *decoder = (FLAC__StreamDecoder *)client_data;

        if(
#if FLAC__HAS_OGG
                /* see [1] HACK NOTE below for why we don't call the eof_callback when decoding Ogg FLAC */
                !decoder->private_->is_ogg &&
#endif
                decoder->private_->eof_callback && decoder->private_->eof_callback(decoder, decoder->private_->client_data)
        ) {
                *bytes = 0;
                decoder->protected_->state = FLAC__STREAM_DECODER_END_OF_STREAM;
                return false;
        }
        else if(*bytes > 0) {
                /* While seeking, it is possible for our seek to land in the
                 * middle of audio data that looks exactly like a frame header
                 * from a future version of an encoder.  When that happens, our
                 * error callback will get an
                 * FLAC__STREAM_DECODER_UNPARSEABLE_STREAM and increment its
                 * unparseable_frame_count.  But there is a remote possibility
                 * that it is properly synced at such a "future-codec frame",
                 * so to make sure, we wait to see many "unparseable" errors in
                 * a row before bailing out.
                 */
                if(decoder->private_->is_seeking && decoder->private_->unparseable_frame_count > 20) {
                        decoder->protected_->state = FLAC__STREAM_DECODER_ABORTED;
                        return false;
                }
                else {
                        const FLAC__StreamDecoderReadStatus status =
#if FLAC__HAS_OGG
                                decoder->private_->is_ogg?
                                read_callback_ogg_aspect_(decoder, buffer, bytes) :
#endif
                                decoder->private_->read_callback(decoder, buffer, bytes, decoder->private_->client_data)
                        ;
                        if(status == FLAC__STREAM_DECODER_READ_STATUS_ABORT) {
                                decoder->protected_->state = FLAC__STREAM_DECODER_ABORTED;
                                return false;
                        }
                        else if(*bytes == 0) {
                                if(
                                        status == FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM ||
                                        (
#if FLAC__HAS_OGG
                                                /* see [1] HACK NOTE below for why we don't call the eof_callback when decoding Ogg FLAC */
                                                !decoder->private_->is_ogg &&
#endif
                                                decoder->private_->eof_callback && decoder->private_->eof_callback(decoder, decoder->private_->client_data)
                                        )
                                ) {
                                        decoder->protected_->state = FLAC__STREAM_DECODER_END_OF_STREAM;
                                        return false;
                                }
                                else
                                        return true;
                        }
                        else
                                return true;
                }
        }
        else {
                /* abort to avoid a deadlock */
                decoder->protected_->state = FLAC__STREAM_DECODER_ABORTED;
                return false;
        }
        /* [1] @@@ HACK NOTE: The end-of-stream checking has to be hacked around
         * for Ogg FLAC.  This is because the ogg decoder aspect can lose sync
         * and at the same time hit the end of the stream (for example, seeking
         * to a point that is after the beginning of the last Ogg page).  There
         * is no way to report an Ogg sync loss through the callbacks (see note
         * in read_callback_ogg_aspect_()) so it returns CONTINUE with *bytes==0.
         * So to keep the decoder from stopping at this point we gate the call
         * to the eof_callback and let the Ogg decoder aspect set the
         * end-of-stream state when it is needed.
         */
}

#if FLAC__HAS_OGG
FLAC__StreamDecoderReadStatus read_callback_ogg_aspect_(const FLAC__StreamDecoder *decoder, FLAC__byte buffer[], size_t *bytes)
{
        switch(FLAC__ogg_decoder_aspect_read_callback_wrapper(&decoder->protected_->ogg_decoder_aspect, buffer, bytes, read_callback_proxy_, decoder, decoder->private_->client_data)) {
                case FLAC__OGG_DECODER_ASPECT_READ_STATUS_OK:
                        return FLAC__STREAM_DECODER_READ_STATUS_CONTINUE;
                /* we don't really have a way to handle lost sync via read
                 * callback so we'll let it pass and let the underlying
                 * FLAC decoder catch the error
                 */
                case FLAC__OGG_DECODER_ASPECT_READ_STATUS_LOST_SYNC:
                        return FLAC__STREAM_DECODER_READ_STATUS_CONTINUE;
                case FLAC__OGG_DECODER_ASPECT_READ_STATUS_END_OF_STREAM:
                        return FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM;
                case FLAC__OGG_DECODER_ASPECT_READ_STATUS_NOT_FLAC:
                case FLAC__OGG_DECODER_ASPECT_READ_STATUS_UNSUPPORTED_MAPPING_VERSION:
                case FLAC__OGG_DECODER_ASPECT_READ_STATUS_ABORT:
                case FLAC__OGG_DECODER_ASPECT_READ_STATUS_ERROR:
                case FLAC__OGG_DECODER_ASPECT_READ_STATUS_MEMORY_ALLOCATION_ERROR:
                        return FLAC__STREAM_DECODER_READ_STATUS_ABORT;
                default:
                        FLAC__ASSERT(0);
                        /* double protection */
                        return FLAC__STREAM_DECODER_READ_STATUS_ABORT;
        }
}

FLAC__OggDecoderAspectReadStatus read_callback_proxy_(const void *void_decoder, FLAC__byte buffer[], size_t *bytes, void *client_data)
{
        FLAC__StreamDecoder *decoder = (FLAC__StreamDecoder*)void_decoder;

        switch(decoder->private_->read_callback(decoder, buffer, bytes, client_data)) {
                case FLAC__STREAM_DECODER_READ_STATUS_CONTINUE:
                        return FLAC__OGG_DECODER_ASPECT_READ_STATUS_OK;
                case FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM:
                        return FLAC__OGG_DECODER_ASPECT_READ_STATUS_END_OF_STREAM;
                case FLAC__STREAM_DECODER_READ_STATUS_ABORT:
                        return FLAC__OGG_DECODER_ASPECT_READ_STATUS_ABORT;
                default:
                        /* double protection: */
                        FLAC__ASSERT(0);
                        return FLAC__OGG_DECODER_ASPECT_READ_STATUS_ABORT;
        }
}
#endif

FLAC__StreamDecoderWriteStatus write_audio_frame_to_client_(FLAC__StreamDecoder *decoder, const FLAC__Frame *frame, const FLAC__int32 * const buffer[])
{
        if(decoder->private_->is_seeking) {
                FLAC__uint64 this_frame_sample = frame->header.number.sample_number;
                FLAC__uint64 next_frame_sample = this_frame_sample + (FLAC__uint64)frame->header.blocksize;
                FLAC__uint64 target_sample = decoder->private_->target_sample;

                FLAC__ASSERT(frame->header.number_type == FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER);

#if FLAC__HAS_OGG
                decoder->private_->got_a_frame = true;
#endif
                decoder->private_->last_frame = *frame; /* save the frame */
                if(this_frame_sample <= target_sample && target_sample < next_frame_sample) { /* we hit our target frame */
                        uint32_t delta = (uint32_t)(target_sample - this_frame_sample);
                        /* kick out of seek mode */
                        decoder->private_->is_seeking = false;
                        /* shift out the samples before target_sample */
                        if(delta > 0) {
                                uint32_t channel;
                                const FLAC__int32 *newbuffer[FLAC__MAX_CHANNELS];
                                for(channel = 0; channel < frame->header.channels; channel++)
                                        newbuffer[channel] = buffer[channel] + delta;
                                decoder->private_->last_frame.header.blocksize -= delta;
                                decoder->private_->last_frame.header.number.sample_number += (FLAC__uint64)delta;
                                /* write the relevant samples */
                                return decoder->private_->write_callback(decoder, &decoder->private_->last_frame, newbuffer, decoder->private_->client_data);
                        }
                        else {
                                /* write the relevant samples */
                                return decoder->private_->write_callback(decoder, frame, buffer, decoder->private_->client_data);
                        }
                }
                else {
                        return FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE;
                }
        }
        else {
                /*
                 * If we never got STREAMINFO, turn off MD5 checking to save
                 * cycles since we don't have a sum to compare to anyway
                 */
                if(!decoder->private_->has_stream_info)
                        decoder->private_->do_md5_checking = false;
                if(decoder->private_->do_md5_checking) {
                        if(!FLAC__MD5Accumulate(&decoder->private_->md5context, buffer, frame->header.channels, frame->header.blocksize, (frame->header.bits_per_sample+7) / 8))
                                return FLAC__STREAM_DECODER_WRITE_STATUS_ABORT;
                }
                return decoder->private_->write_callback(decoder, frame, buffer, decoder->private_->client_data);
        }
}

void send_error_to_client_(const FLAC__StreamDecoder *decoder, FLAC__StreamDecoderErrorStatus status)
{
        if(!decoder->private_->is_seeking)
                decoder->private_->error_callback(decoder, status, decoder->private_->client_data);
        else if(status == FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM)
                decoder->private_->unparseable_frame_count++;
}

FLAC__bool seek_to_absolute_sample_(FLAC__StreamDecoder *decoder, FLAC__uint64 stream_length, FLAC__uint64 target_sample)
{
        FLAC__uint64 first_frame_offset = decoder->private_->first_frame_offset, lower_bound, upper_bound, lower_bound_sample, upper_bound_sample, this_frame_sample;
        FLAC__int64 pos = -1;
        int i;
        uint32_t approx_bytes_per_frame;
        FLAC__bool first_seek = true;
        const FLAC__uint64 total_samples = FLAC__stream_decoder_get_total_samples(decoder);
        const uint32_t min_blocksize = decoder->private_->stream_info.data.stream_info.min_blocksize;
        const uint32_t max_blocksize = decoder->private_->stream_info.data.stream_info.max_blocksize;
        const uint32_t max_framesize = decoder->private_->stream_info.data.stream_info.max_framesize;
        const uint32_t min_framesize = decoder->private_->stream_info.data.stream_info.min_framesize;
        /* take these from the current frame in case they've changed mid-stream */
        uint32_t channels = FLAC__stream_decoder_get_channels(decoder);
        uint32_t bps = FLAC__stream_decoder_get_bits_per_sample(decoder);
        const FLAC__StreamMetadata_SeekTable *seek_table = decoder->private_->has_seek_table? &decoder->private_->seek_table.data.seek_table : 0;

        /* use values from stream info if we didn't decode a frame */
        if(channels == 0)
                channels = decoder->private_->stream_info.data.stream_info.channels;
        if(bps == 0)
                bps = decoder->private_->stream_info.data.stream_info.bits_per_sample;

        /* we are just guessing here */
        if(max_framesize > 0)
                approx_bytes_per_frame = (max_framesize + min_framesize) / 2 + 1;
        /*
         * Check if it's a known fixed-blocksize stream.  Note that though
         * the spec doesn't allow zeroes in the STREAMINFO block, we may
         * never get a STREAMINFO block when decoding so the value of
         * min_blocksize might be zero.
         */
        else if(min_blocksize == max_blocksize && min_blocksize > 0) {
                /* note there are no () around 'bps/8' to keep precision up since it's an integer calculation */
                approx_bytes_per_frame = min_blocksize * channels * bps/8 + 64;
        }
        else
                approx_bytes_per_frame = 4096 * channels * bps/8 + 64;

        /*
         * First, we set an upper and lower bound on where in the
         * stream we will search.  For now we assume the worst case
         * scenario, which is our best guess at the beginning of
         * the first frame and end of the stream.
         */
        lower_bound = first_frame_offset;
        lower_bound_sample = 0;
        upper_bound = stream_length;
        upper_bound_sample = total_samples > 0 ? total_samples : target_sample /*estimate it*/;

        /*
         * Now we refine the bounds if we have a seektable with
         * suitable points.  Note that according to the spec they
         * must be ordered by ascending sample number.
         *
         * Note: to protect against invalid seek tables we will ignore points
         * that have frame_samples==0 or sample_number>=total_samples
         */
        if(seek_table) {
                FLAC__uint64 new_lower_bound = lower_bound;
                FLAC__uint64 new_upper_bound = upper_bound;
                FLAC__uint64 new_lower_bound_sample = lower_bound_sample;
                FLAC__uint64 new_upper_bound_sample = upper_bound_sample;

                /* find the closest seek point <= target_sample, if it exists */
                for(i = (int)seek_table->num_points - 1; i >= 0; i--) {
                        if(
                                seek_table->points[i].sample_number != FLAC__STREAM_METADATA_SEEKPOINT_PLACEHOLDER &&
                                seek_table->points[i].frame_samples > 0 && /* defense against bad seekpoints */
                                (total_samples <= 0 || seek_table->points[i].sample_number < total_samples) && /* defense against bad seekpoints */
                                seek_table->points[i].sample_number <= target_sample
                        )
                                break;
                }
                if(i >= 0) { /* i.e. we found a suitable seek point... */
                        new_lower_bound = first_frame_offset + seek_table->points[i].stream_offset;
                        new_lower_bound_sample = seek_table->points[i].sample_number;
                }

                /* find the closest seek point > target_sample, if it exists */
                for(i = 0; i < (int)seek_table->num_points; i++) {
                        if(
                                seek_table->points[i].sample_number != FLAC__STREAM_METADATA_SEEKPOINT_PLACEHOLDER &&
                                seek_table->points[i].frame_samples > 0 && /* defense against bad seekpoints */
                                (total_samples <= 0 || seek_table->points[i].sample_number < total_samples) && /* defense against bad seekpoints */
                                seek_table->points[i].sample_number > target_sample
                        )
                                break;
                }
                if(i < (int)seek_table->num_points) { /* i.e. we found a suitable seek point... */
                        new_upper_bound = first_frame_offset + seek_table->points[i].stream_offset;
                        new_upper_bound_sample = seek_table->points[i].sample_number;
                }
                /* final protection against unsorted seek tables; keep original values if bogus */
                if(new_upper_bound >= new_lower_bound) {
                        lower_bound = new_lower_bound;
                        upper_bound = new_upper_bound;
                        lower_bound_sample = new_lower_bound_sample;
                        upper_bound_sample = new_upper_bound_sample;
                }
        }

        FLAC__ASSERT(upper_bound_sample >= lower_bound_sample);
        /* there are 2 insidious ways that the following equality occurs, which
         * we need to fix:
         *  1) total_samples is 0 (unknown) and target_sample is 0
         *  2) total_samples is 0 (unknown) and target_sample happens to be
         *     exactly equal to the last seek point in the seek table; this
         *     means there is no seek point above it, and upper_bound_samples
         *     remains equal to the estimate (of target_samples) we made above
         * in either case it does not hurt to move upper_bound_sample up by 1
         */
        if(upper_bound_sample == lower_bound_sample)
                upper_bound_sample++;

        decoder->private_->target_sample = target_sample;
        while(1) {
                /* check if the bounds are still ok */
                if (lower_bound_sample >= upper_bound_sample || lower_bound > upper_bound) {
                        decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
                        return false;
                }
#ifndef FLAC__INTEGER_ONLY_LIBRARY
                pos = (FLAC__int64)lower_bound + (FLAC__int64)((double)(target_sample - lower_bound_sample) / (double)(upper_bound_sample - lower_bound_sample) * (double)(upper_bound - lower_bound)) - approx_bytes_per_frame;
#else
                /* a little less accurate: */
                if(upper_bound - lower_bound < 0xffffffff)
                        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;
                else /* @@@ WATCHOUT, ~2TB limit */
                        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;
#endif
                if(pos >= (FLAC__int64)upper_bound)
                        pos = (FLAC__int64)upper_bound - 1;
                if(pos < (FLAC__int64)lower_bound)
                        pos = (FLAC__int64)lower_bound;
                if(decoder->private_->seek_callback(decoder, (FLAC__uint64)pos, decoder->private_->client_data) != FLAC__STREAM_DECODER_SEEK_STATUS_OK) {
                        decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
                        return false;
                }
                if(!FLAC__stream_decoder_flush(decoder)) {
                        /* above call sets the state for us */
                        return false;
                }
                /* Now we need to get a frame.  First we need to reset our
                 * unparseable_frame_count; if we get too many unparseable
                 * frames in a row, the read callback will return
                 * FLAC__STREAM_DECODER_READ_STATUS_ABORT, causing
                 * FLAC__stream_decoder_process_single() to return false.
                 */
                decoder->private_->unparseable_frame_count = 0;
                if(!FLAC__stream_decoder_process_single(decoder) ||
                   decoder->protected_->state == FLAC__STREAM_DECODER_ABORTED) {
                        decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
                        return false;
                }
                /* our write callback will change the state when it gets to the target frame */
                /* 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 */
#if 0
                /*@@@@@@ used to be the following; not clear if the check for end of stream is needed anymore */
                if(decoder->protected_->state != FLAC__SEEKABLE_STREAM_DECODER_SEEKING && decoder->protected_->state != FLAC__STREAM_DECODER_END_OF_STREAM)
                        break;
#endif
                if(!decoder->private_->is_seeking)
                        break;

                FLAC__ASSERT(decoder->private_->last_frame.header.number_type == FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER);
                this_frame_sample = decoder->private_->last_frame.header.number.sample_number;

                if (0 == decoder->private_->samples_decoded || (this_frame_sample + decoder->private_->last_frame.header.blocksize >= upper_bound_sample && !first_seek)) {
                        if (pos == (FLAC__int64)lower_bound) {
                                /* can't move back any more than the first frame, something is fatally wrong */
                                decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
                                return false;
                        }
                        /* our last move backwards wasn't big enough, try again */
                        approx_bytes_per_frame = approx_bytes_per_frame? approx_bytes_per_frame * 2 : 16;
                        continue;
                }
                /* allow one seek over upper bound, so we can get a correct upper_bound_sample for streams with unknown total_samples */
                first_seek = false;

                /* make sure we are not seeking in corrupted stream */
                if (this_frame_sample < lower_bound_sample) {
                        decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
                        return false;
                }

                /* we need to narrow the search */
                if(target_sample < this_frame_sample) {
                        upper_bound_sample = this_frame_sample + decoder->private_->last_frame.header.blocksize;
/*@@@@@@ what will decode position be if at end of stream? */
                        if(!FLAC__stream_decoder_get_decode_position(decoder, &upper_bound)) {
                                decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
                                return false;
                        }
                        approx_bytes_per_frame = (uint32_t)(2 * (upper_bound - pos) / 3 + 16);
                }
                else { /* target_sample >= this_frame_sample + this frame's blocksize */
                        lower_bound_sample = this_frame_sample + decoder->private_->last_frame.header.blocksize;
                        if(!FLAC__stream_decoder_get_decode_position(decoder, &lower_bound)) {
                                decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
                                return false;
                        }
                        approx_bytes_per_frame = (uint32_t)(2 * (lower_bound - pos) / 3 + 16);
                }
        }

        return true;
}

#if FLAC__HAS_OGG
FLAC__bool seek_to_absolute_sample_ogg_(FLAC__StreamDecoder *decoder, FLAC__uint64 stream_length, FLAC__uint64 target_sample)
{
        FLAC__uint64 left_pos = 0, right_pos = stream_length;
        FLAC__uint64 left_sample = 0, right_sample = FLAC__stream_decoder_get_total_samples(decoder);
        FLAC__uint64 this_frame_sample = (FLAC__uint64)0 - 1;
        FLAC__uint64 pos = 0; /* only initialized to avoid compiler warning */
        FLAC__bool did_a_seek;
        uint32_t iteration = 0;

        /* In the first iterations, we will calculate the target byte position
         * by the distance from the target sample to left_sample and
         * right_sample (let's call it "proportional search").  After that, we
         * will switch to binary search.
         */
        uint32_t BINARY_SEARCH_AFTER_ITERATION = 2;

        /* We will switch to a linear search once our current sample is less
         * than this number of samples ahead of the target sample
         */
        static const FLAC__uint64 LINEAR_SEARCH_WITHIN_SAMPLES = FLAC__MAX_BLOCK_SIZE * 2;

        /* If the total number of samples is unknown, use a large value, and
         * force binary search immediately.
         */
        if(right_sample == 0) {
                right_sample = (FLAC__uint64)(-1);
                BINARY_SEARCH_AFTER_ITERATION = 0;
        }

        decoder->private_->target_sample = target_sample;
        for( ; ; iteration++) {
                if (iteration == 0 || this_frame_sample > target_sample || target_sample - this_frame_sample > LINEAR_SEARCH_WITHIN_SAMPLES) {
                        if (iteration >= BINARY_SEARCH_AFTER_ITERATION) {
                                pos = (right_pos + left_pos) / 2;
                        }
                        else {
#ifndef FLAC__INTEGER_ONLY_LIBRARY
                                pos = (FLAC__uint64)((double)(target_sample - left_sample) / (double)(right_sample - left_sample) * (double)(right_pos - left_pos));
#else
                                /* a little less accurate: */
                                if ((target_sample-left_sample <= 0xffffffff) && (right_pos-left_pos <= 0xffffffff))
                                        pos = (FLAC__int64)(((target_sample-left_sample) * (right_pos-left_pos)) / (right_sample-left_sample));
                                else /* @@@ WATCHOUT, ~2TB limit */
                                        pos = (FLAC__int64)((((target_sample-left_sample)>>8) * ((right_pos-left_pos)>>8)) / ((right_sample-left_sample)>>16));
#endif
                                /* @@@ TODO: might want to limit pos to some distance
                                 * before EOF, to make sure we land before the last frame,
                                 * thereby getting a this_frame_sample and so having a better
                                 * estimate.
                                 */
                        }

                        /* physical seek */
                        if(decoder->private_->seek_callback((FLAC__StreamDecoder*)decoder, (FLAC__uint64)pos, decoder->private_->client_data) != FLAC__STREAM_DECODER_SEEK_STATUS_OK) {
                                decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
                                return false;
                        }
                        if(!FLAC__stream_decoder_flush(decoder)) {
                                /* above call sets the state for us */
                                return false;
                        }
                        did_a_seek = true;
                }
                else
                        did_a_seek = false;

                decoder->private_->got_a_frame = false;
                if(!FLAC__stream_decoder_process_single(decoder) ||
                   decoder->protected_->state == FLAC__STREAM_DECODER_ABORTED) {
                        decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
                        return false;
                }
                if(!decoder->private_->got_a_frame) {
                        if(did_a_seek) {
                                /* this can happen if we seek to a point after the last frame; we drop
                                 * to binary search right away in this case to avoid any wasted
                                 * iterations of proportional search.
                                 */
                                right_pos = pos;
                                BINARY_SEARCH_AFTER_ITERATION = 0;
                        }
                        else {
                                /* this can probably only happen if total_samples is unknown and the
                                 * target_sample is past the end of the stream
                                 */
                                decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
                                return false;
                        }
                }
                /* our write callback will change the state when it gets to the target frame */
                else if(!decoder->private_->is_seeking) {
                        break;
                }
                else {
                        this_frame_sample = decoder->private_->last_frame.header.number.sample_number;
                        FLAC__ASSERT(decoder->private_->last_frame.header.number_type == FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER);

                        if (did_a_seek) {
                                if (this_frame_sample <= target_sample) {
                                        /* The 'equal' case should not happen, since
                                         * FLAC__stream_decoder_process_single()
                                         * should recognize that it has hit the
                                         * target sample and we would exit through
                                         * the 'break' above.
                                         */
                                        FLAC__ASSERT(this_frame_sample != target_sample);

                                        left_sample = this_frame_sample;
                                        /* sanity check to avoid infinite loop */
                                        if (left_pos == pos) {
                                                decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
                                                return false;
                                        }
                                        left_pos = pos;
                                }
                                else if(this_frame_sample > target_sample) {
                                        right_sample = this_frame_sample;
                                        /* sanity check to avoid infinite loop */
                                        if (right_pos == pos) {
                                                decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
                                                return false;
                                        }
                                        right_pos = pos;
                                }
                        }
                }
        }

        return true;
}
#endif

FLAC__StreamDecoderReadStatus file_read_callback_(const FLAC__StreamDecoder *decoder, FLAC__byte buffer[], size_t *bytes, void *client_data)
{
        (void)client_data;

        if(*bytes > 0) {
                *bytes = fread(buffer, sizeof(FLAC__byte), *bytes, decoder->private_->file);
                if(ferror(decoder->private_->file))
                        return FLAC__STREAM_DECODER_READ_STATUS_ABORT;
                else if(*bytes == 0)
                        return FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM;
                else
                        return FLAC__STREAM_DECODER_READ_STATUS_CONTINUE;
        }
        else
                return FLAC__STREAM_DECODER_READ_STATUS_ABORT; /* abort to avoid a deadlock */
}

FLAC__StreamDecoderSeekStatus file_seek_callback_(const FLAC__StreamDecoder *decoder, FLAC__uint64 absolute_byte_offset, void *client_data)
{
        (void)client_data;

        if(decoder->private_->file == stdin)
                return FLAC__STREAM_DECODER_SEEK_STATUS_UNSUPPORTED;
        else if(fseeko(decoder->private_->file, (FLAC__off_t)absolute_byte_offset, SEEK_SET) < 0)
                return FLAC__STREAM_DECODER_SEEK_STATUS_ERROR;
        else
                return FLAC__STREAM_DECODER_SEEK_STATUS_OK;
}

FLAC__StreamDecoderTellStatus file_tell_callback_(const FLAC__StreamDecoder *decoder, FLAC__uint64 *absolute_byte_offset, void *client_data)
{
        FLAC__off_t pos;
        (void)client_data;

        if(decoder->private_->file == stdin)
                return FLAC__STREAM_DECODER_TELL_STATUS_UNSUPPORTED;
        else if((pos = ftello(decoder->private_->file)) < 0)
                return FLAC__STREAM_DECODER_TELL_STATUS_ERROR;
        else {
                *absolute_byte_offset = (FLAC__uint64)pos;
                return FLAC__STREAM_DECODER_TELL_STATUS_OK;
        }
}

FLAC__StreamDecoderLengthStatus file_length_callback_(const FLAC__StreamDecoder *decoder, FLAC__uint64 *stream_length, void *client_data)
{
        struct flac_stat_s filestats;
        (void)client_data;

        if(decoder->private_->file == stdin)
                return FLAC__STREAM_DECODER_LENGTH_STATUS_UNSUPPORTED;
        else if(flac_fstat(fileno(decoder->private_->file), &filestats) != 0)
                return FLAC__STREAM_DECODER_LENGTH_STATUS_ERROR;
        else {
                *stream_length = (FLAC__uint64)filestats.st_size;
                return FLAC__STREAM_DECODER_LENGTH_STATUS_OK;
        }
}

FLAC__bool file_eof_callback_(const FLAC__StreamDecoder *decoder, void *client_data)
{
        (void)client_data;

        return feof(decoder->private_->file)? true : false;
}

FLAC_API const void *FLAC__get_decoder_client_data(FLAC__StreamDecoder *decoder)
{
        return decoder->private_->client_data;
}