| /* libFLAC - Free Lossless Audio Codec library |
| * Copyright (C) 2000,2001,2002,2003,2004,2005,2006 Josh Coalson |
| * |
| * 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. |
| */ |
| |
| #include <stdio.h> |
| #include <stdlib.h> /* for calloc() */ |
| #include <string.h> /* for memcpy()/memcmp() */ |
| #include "FLAC/assert.h" |
| #include "protected/seekable_stream_decoder.h" |
| #include "protected/stream_decoder.h" |
| #include "private/float.h" /* for FLAC__double */ |
| #include "private/md5.h" |
| |
| /* adjust for compilers that can't understand using LLU suffix for uint64_t literals */ |
| #ifdef _MSC_VER |
| #define FLAC__U64L(x) x |
| #else |
| #define FLAC__U64L(x) x##LLU |
| #endif |
| |
| /*********************************************************************** |
| * |
| * Private class method prototypes |
| * |
| ***********************************************************************/ |
| |
| static void set_defaults_(FLAC__SeekableStreamDecoder *decoder); |
| static FLAC__StreamDecoderReadStatus read_callback_(const FLAC__StreamDecoder *decoder, FLAC__byte buffer[], unsigned *bytes, void *client_data); |
| static FLAC__StreamDecoderWriteStatus write_callback_(const FLAC__StreamDecoder *decoder, const FLAC__Frame *frame, const FLAC__int32 * const buffer[], void *client_data); |
| static void metadata_callback_(const FLAC__StreamDecoder *decoder, const FLAC__StreamMetadata *metadata, void *client_data); |
| static void error_callback_(const FLAC__StreamDecoder *decoder, FLAC__StreamDecoderErrorStatus status, void *client_data); |
| static FLAC__bool seek_to_absolute_sample_(FLAC__SeekableStreamDecoder *decoder, FLAC__uint64 stream_length, FLAC__uint64 target_sample); |
| |
| /*********************************************************************** |
| * |
| * Private class data |
| * |
| ***********************************************************************/ |
| |
| typedef struct FLAC__SeekableStreamDecoderPrivate { |
| FLAC__SeekableStreamDecoderReadCallback read_callback; |
| FLAC__SeekableStreamDecoderSeekCallback seek_callback; |
| FLAC__SeekableStreamDecoderTellCallback tell_callback; |
| FLAC__SeekableStreamDecoderLengthCallback length_callback; |
| FLAC__SeekableStreamDecoderEofCallback eof_callback; |
| FLAC__SeekableStreamDecoderWriteCallback write_callback; |
| FLAC__SeekableStreamDecoderMetadataCallback metadata_callback; |
| FLAC__SeekableStreamDecoderErrorCallback error_callback; |
| void *client_data; |
| FLAC__StreamDecoder *stream_decoder; |
| FLAC__bool do_md5_checking; /* initially gets protected_->md5_checking but is turned off after a seek */ |
| struct FLAC__MD5Context md5context; |
| FLAC__byte stored_md5sum[16]; /* this is what is stored in the metadata */ |
| 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__StreamMetadata_StreamInfo stream_info; /* we keep this around so we can figure out how to seek quickly */ |
| const FLAC__StreamMetadata_SeekTable *seek_table; /* we hold a pointer to the stream decoder's seek table for the same reason */ |
| /* Since we always want to see the STREAMINFO and SEEK_TABLE blocks at this level, we need some extra flags to keep track of whether they should be passed on up through the metadata_callback */ |
| FLAC__bool ignore_stream_info_block; |
| FLAC__bool ignore_seek_table_block; |
| FLAC__Frame last_frame; /* holds the info of the last frame we seeked to */ |
| FLAC__uint64 target_sample; |
| } FLAC__SeekableStreamDecoderPrivate; |
| |
| /*********************************************************************** |
| * |
| * Public static class data |
| * |
| ***********************************************************************/ |
| |
| FLAC_API const char * const FLAC__SeekableStreamDecoderStateString[] = { |
| "FLAC__SEEKABLE_STREAM_DECODER_OK", |
| "FLAC__SEEKABLE_STREAM_DECODER_SEEKING", |
| "FLAC__SEEKABLE_STREAM_DECODER_END_OF_STREAM", |
| "FLAC__SEEKABLE_STREAM_DECODER_MEMORY_ALLOCATION_ERROR", |
| "FLAC__SEEKABLE_STREAM_DECODER_STREAM_DECODER_ERROR", |
| "FLAC__SEEKABLE_STREAM_DECODER_READ_ERROR", |
| "FLAC__SEEKABLE_STREAM_DECODER_SEEK_ERROR", |
| "FLAC__SEEKABLE_STREAM_DECODER_ALREADY_INITIALIZED", |
| "FLAC__SEEKABLE_STREAM_DECODER_INVALID_CALLBACK", |
| "FLAC__SEEKABLE_STREAM_DECODER_UNINITIALIZED" |
| }; |
| |
| FLAC_API const char * const FLAC__SeekableStreamDecoderReadStatusString[] = { |
| "FLAC__SEEKABLE_STREAM_DECODER_READ_STATUS_OK", |
| "FLAC__SEEKABLE_STREAM_DECODER_READ_STATUS_ERROR" |
| }; |
| |
| FLAC_API const char * const FLAC__SeekableStreamDecoderSeekStatusString[] = { |
| "FLAC__SEEKABLE_STREAM_DECODER_SEEK_STATUS_OK", |
| "FLAC__SEEKABLE_STREAM_DECODER_SEEK_STATUS_ERROR" |
| }; |
| |
| FLAC_API const char * const FLAC__SeekableStreamDecoderTellStatusString[] = { |
| "FLAC__SEEKABLE_STREAM_DECODER_TELL_STATUS_OK", |
| "FLAC__SEEKABLE_STREAM_DECODER_TELL_STATUS_ERROR" |
| }; |
| |
| FLAC_API const char * const FLAC__SeekableStreamDecoderLengthStatusString[] = { |
| "FLAC__SEEKABLE_STREAM_DECODER_LENGTH_STATUS_OK", |
| "FLAC__SEEKABLE_STREAM_DECODER_LENGTH_STATUS_ERROR" |
| }; |
| |
| |
| /*********************************************************************** |
| * |
| * Class constructor/destructor |
| * |
| ***********************************************************************/ |
| |
| FLAC_API FLAC__SeekableStreamDecoder *FLAC__seekable_stream_decoder_new() |
| { |
| FLAC__SeekableStreamDecoder *decoder; |
| |
| FLAC__ASSERT(sizeof(int) >= 4); /* we want to die right away if this is not true */ |
| |
| decoder = (FLAC__SeekableStreamDecoder*)calloc(1, sizeof(FLAC__SeekableStreamDecoder)); |
| if(decoder == 0) { |
| return 0; |
| } |
| |
| decoder->protected_ = (FLAC__SeekableStreamDecoderProtected*)calloc(1, sizeof(FLAC__SeekableStreamDecoderProtected)); |
| if(decoder->protected_ == 0) { |
| free(decoder); |
| return 0; |
| } |
| |
| decoder->private_ = (FLAC__SeekableStreamDecoderPrivate*)calloc(1, sizeof(FLAC__SeekableStreamDecoderPrivate)); |
| if(decoder->private_ == 0) { |
| free(decoder->protected_); |
| free(decoder); |
| return 0; |
| } |
| |
| decoder->private_->stream_decoder = FLAC__stream_decoder_new(); |
| if(0 == decoder->private_->stream_decoder) { |
| free(decoder->private_); |
| free(decoder->protected_); |
| free(decoder); |
| return 0; |
| } |
| |
| set_defaults_(decoder); |
| |
| decoder->protected_->state = FLAC__SEEKABLE_STREAM_DECODER_UNINITIALIZED; |
| |
| return decoder; |
| } |
| |
| FLAC_API void FLAC__seekable_stream_decoder_delete(FLAC__SeekableStreamDecoder *decoder) |
| { |
| FLAC__ASSERT(0 != decoder); |
| FLAC__ASSERT(0 != decoder->protected_); |
| FLAC__ASSERT(0 != decoder->private_); |
| FLAC__ASSERT(0 != decoder->private_->stream_decoder); |
| |
| (void)FLAC__seekable_stream_decoder_finish(decoder); |
| |
| FLAC__stream_decoder_delete(decoder->private_->stream_decoder); |
| |
| free(decoder->private_); |
| free(decoder->protected_); |
| free(decoder); |
| } |
| |
| /*********************************************************************** |
| * |
| * Public class methods |
| * |
| ***********************************************************************/ |
| |
| FLAC_API FLAC__SeekableStreamDecoderState FLAC__seekable_stream_decoder_init(FLAC__SeekableStreamDecoder *decoder) |
| { |
| FLAC__ASSERT(0 != decoder); |
| |
| if(decoder->protected_->state != FLAC__SEEKABLE_STREAM_DECODER_UNINITIALIZED) |
| return decoder->protected_->state = FLAC__SEEKABLE_STREAM_DECODER_ALREADY_INITIALIZED; |
| |
| if(0 == decoder->private_->read_callback || 0 == decoder->private_->seek_callback || 0 == decoder->private_->tell_callback || 0 == decoder->private_->length_callback || 0 == decoder->private_->eof_callback) |
| return decoder->protected_->state = FLAC__SEEKABLE_STREAM_DECODER_INVALID_CALLBACK; |
| |
| if(0 == decoder->private_->write_callback || 0 == decoder->private_->metadata_callback || 0 == decoder->private_->error_callback) |
| return decoder->protected_->state = FLAC__SEEKABLE_STREAM_DECODER_INVALID_CALLBACK; |
| |
| decoder->private_->seek_table = 0; |
| |
| decoder->private_->do_md5_checking = decoder->protected_->md5_checking; |
| |
| /* 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 always init the context here and finalize it in |
| * FLAC__seekable_stream_decoder_finish() to make sure things are always |
| * cleaned up properly. |
| */ |
| FLAC__MD5Init(&decoder->private_->md5context); |
| |
| FLAC__stream_decoder_set_read_callback(decoder->private_->stream_decoder, read_callback_); |
| FLAC__stream_decoder_set_write_callback(decoder->private_->stream_decoder, write_callback_); |
| FLAC__stream_decoder_set_metadata_callback(decoder->private_->stream_decoder, metadata_callback_); |
| FLAC__stream_decoder_set_error_callback(decoder->private_->stream_decoder, error_callback_); |
| FLAC__stream_decoder_set_client_data(decoder->private_->stream_decoder, decoder); |
| |
| /* We always want to see these blocks. Whether or not we pass them up |
| * through the metadata callback will be determined by flags set in our |
| * implementation of ..._set_metadata_respond/ignore...() |
| */ |
| FLAC__stream_decoder_set_metadata_respond(decoder->private_->stream_decoder, FLAC__METADATA_TYPE_STREAMINFO); |
| FLAC__stream_decoder_set_metadata_respond(decoder->private_->stream_decoder, FLAC__METADATA_TYPE_SEEKTABLE); |
| |
| if(FLAC__stream_decoder_init(decoder->private_->stream_decoder) != FLAC__STREAM_DECODER_SEARCH_FOR_METADATA) |
| return decoder->protected_->state = FLAC__SEEKABLE_STREAM_DECODER_STREAM_DECODER_ERROR; |
| |
| return decoder->protected_->state = FLAC__SEEKABLE_STREAM_DECODER_OK; |
| } |
| |
| FLAC_API FLAC__bool FLAC__seekable_stream_decoder_finish(FLAC__SeekableStreamDecoder *decoder) |
| { |
| FLAC__bool md5_failed = false; |
| |
| FLAC__ASSERT(0 != decoder); |
| FLAC__ASSERT(0 != decoder->private_); |
| FLAC__ASSERT(0 != decoder->protected_); |
| |
| if(decoder->protected_->state == FLAC__SEEKABLE_STREAM_DECODER_UNINITIALIZED) |
| return true; |
| |
| FLAC__ASSERT(0 != decoder->private_->stream_decoder); |
| |
| /* see the comment in FLAC__seekable_stream_decoder_init() as to why we |
| * always call FLAC__MD5Final() |
| */ |
| FLAC__MD5Final(decoder->private_->computed_md5sum, &decoder->private_->md5context); |
| |
| FLAC__stream_decoder_finish(decoder->private_->stream_decoder); |
| |
| if(decoder->private_->do_md5_checking) { |
| if(memcmp(decoder->private_->stored_md5sum, decoder->private_->computed_md5sum, 16)) |
| md5_failed = true; |
| } |
| |
| set_defaults_(decoder); |
| |
| decoder->protected_->state = FLAC__SEEKABLE_STREAM_DECODER_UNINITIALIZED; |
| |
| return !md5_failed; |
| } |
| |
| FLAC_API FLAC__bool FLAC__seekable_stream_decoder_set_md5_checking(FLAC__SeekableStreamDecoder *decoder, FLAC__bool value) |
| { |
| FLAC__ASSERT(0 != decoder); |
| FLAC__ASSERT(0 != decoder->protected_); |
| if(decoder->protected_->state != FLAC__SEEKABLE_STREAM_DECODER_UNINITIALIZED) |
| return false; |
| decoder->protected_->md5_checking = value; |
| return true; |
| } |
| |
| FLAC_API FLAC__bool FLAC__seekable_stream_decoder_set_read_callback(FLAC__SeekableStreamDecoder *decoder, FLAC__SeekableStreamDecoderReadCallback value) |
| { |
| FLAC__ASSERT(0 != decoder); |
| FLAC__ASSERT(0 != decoder->private_); |
| FLAC__ASSERT(0 != decoder->protected_); |
| if(decoder->protected_->state != FLAC__SEEKABLE_STREAM_DECODER_UNINITIALIZED) |
| return false; |
| decoder->private_->read_callback = value; |
| return true; |
| } |
| |
| FLAC_API FLAC__bool FLAC__seekable_stream_decoder_set_seek_callback(FLAC__SeekableStreamDecoder *decoder, FLAC__SeekableStreamDecoderSeekCallback value) |
| { |
| FLAC__ASSERT(0 != decoder); |
| FLAC__ASSERT(0 != decoder->private_); |
| FLAC__ASSERT(0 != decoder->protected_); |
| if(decoder->protected_->state != FLAC__SEEKABLE_STREAM_DECODER_UNINITIALIZED) |
| return false; |
| decoder->private_->seek_callback = value; |
| return true; |
| } |
| |
| FLAC_API FLAC__bool FLAC__seekable_stream_decoder_set_tell_callback(FLAC__SeekableStreamDecoder *decoder, FLAC__SeekableStreamDecoderTellCallback value) |
| { |
| FLAC__ASSERT(0 != decoder); |
| FLAC__ASSERT(0 != decoder->private_); |
| FLAC__ASSERT(0 != decoder->protected_); |
| if(decoder->protected_->state != FLAC__SEEKABLE_STREAM_DECODER_UNINITIALIZED) |
| return false; |
| decoder->private_->tell_callback = value; |
| return true; |
| } |
| |
| FLAC_API FLAC__bool FLAC__seekable_stream_decoder_set_length_callback(FLAC__SeekableStreamDecoder *decoder, FLAC__SeekableStreamDecoderLengthCallback value) |
| { |
| FLAC__ASSERT(0 != decoder); |
| FLAC__ASSERT(0 != decoder->private_); |
| FLAC__ASSERT(0 != decoder->protected_); |
| if(decoder->protected_->state != FLAC__SEEKABLE_STREAM_DECODER_UNINITIALIZED) |
| return false; |
| decoder->private_->length_callback = value; |
| return true; |
| } |
| |
| FLAC_API FLAC__bool FLAC__seekable_stream_decoder_set_eof_callback(FLAC__SeekableStreamDecoder *decoder, FLAC__SeekableStreamDecoderEofCallback value) |
| { |
| FLAC__ASSERT(0 != decoder); |
| FLAC__ASSERT(0 != decoder->private_); |
| FLAC__ASSERT(0 != decoder->protected_); |
| if(decoder->protected_->state != FLAC__SEEKABLE_STREAM_DECODER_UNINITIALIZED) |
| return false; |
| decoder->private_->eof_callback = value; |
| return true; |
| } |
| |
| FLAC_API FLAC__bool FLAC__seekable_stream_decoder_set_write_callback(FLAC__SeekableStreamDecoder *decoder, FLAC__SeekableStreamDecoderWriteCallback value) |
| { |
| FLAC__ASSERT(0 != decoder); |
| FLAC__ASSERT(0 != decoder->private_); |
| FLAC__ASSERT(0 != decoder->protected_); |
| if(decoder->protected_->state != FLAC__SEEKABLE_STREAM_DECODER_UNINITIALIZED) |
| return false; |
| decoder->private_->write_callback = value; |
| return true; |
| } |
| |
| FLAC_API FLAC__bool FLAC__seekable_stream_decoder_set_metadata_callback(FLAC__SeekableStreamDecoder *decoder, FLAC__SeekableStreamDecoderMetadataCallback value) |
| { |
| FLAC__ASSERT(0 != decoder); |
| FLAC__ASSERT(0 != decoder->private_); |
| FLAC__ASSERT(0 != decoder->protected_); |
| if(decoder->protected_->state != FLAC__SEEKABLE_STREAM_DECODER_UNINITIALIZED) |
| return false; |
| decoder->private_->metadata_callback = value; |
| return true; |
| } |
| |
| FLAC_API FLAC__bool FLAC__seekable_stream_decoder_set_error_callback(FLAC__SeekableStreamDecoder *decoder, FLAC__SeekableStreamDecoderErrorCallback value) |
| { |
| FLAC__ASSERT(0 != decoder); |
| FLAC__ASSERT(0 != decoder->private_); |
| FLAC__ASSERT(0 != decoder->protected_); |
| if(decoder->protected_->state != FLAC__SEEKABLE_STREAM_DECODER_UNINITIALIZED) |
| return false; |
| decoder->private_->error_callback = value; |
| return true; |
| } |
| |
| FLAC_API FLAC__bool FLAC__seekable_stream_decoder_set_client_data(FLAC__SeekableStreamDecoder *decoder, void *value) |
| { |
| FLAC__ASSERT(0 != decoder); |
| FLAC__ASSERT(0 != decoder->private_); |
| FLAC__ASSERT(0 != decoder->protected_); |
| if(decoder->protected_->state != FLAC__SEEKABLE_STREAM_DECODER_UNINITIALIZED) |
| return false; |
| decoder->private_->client_data = value; |
| return true; |
| } |
| |
| FLAC_API FLAC__bool FLAC__seekable_stream_decoder_set_metadata_respond(FLAC__SeekableStreamDecoder *decoder, FLAC__MetadataType type) |
| { |
| FLAC__ASSERT(0 != decoder); |
| FLAC__ASSERT(0 != decoder->private_); |
| FLAC__ASSERT(0 != decoder->protected_); |
| FLAC__ASSERT(0 != decoder->private_->stream_decoder); |
| if(decoder->protected_->state != FLAC__SEEKABLE_STREAM_DECODER_UNINITIALIZED) |
| return false; |
| if(type == FLAC__METADATA_TYPE_STREAMINFO) |
| decoder->private_->ignore_stream_info_block = false; |
| else if(type == FLAC__METADATA_TYPE_SEEKTABLE) |
| decoder->private_->ignore_seek_table_block = false; |
| return FLAC__stream_decoder_set_metadata_respond(decoder->private_->stream_decoder, type); |
| } |
| |
| FLAC_API FLAC__bool FLAC__seekable_stream_decoder_set_metadata_respond_application(FLAC__SeekableStreamDecoder *decoder, const FLAC__byte id[4]) |
| { |
| FLAC__ASSERT(0 != decoder); |
| FLAC__ASSERT(0 != decoder->private_); |
| FLAC__ASSERT(0 != decoder->protected_); |
| FLAC__ASSERT(0 != decoder->private_->stream_decoder); |
| if(decoder->protected_->state != FLAC__SEEKABLE_STREAM_DECODER_UNINITIALIZED) |
| return false; |
| return FLAC__stream_decoder_set_metadata_respond_application(decoder->private_->stream_decoder, id); |
| } |
| |
| FLAC_API FLAC__bool FLAC__seekable_stream_decoder_set_metadata_respond_all(FLAC__SeekableStreamDecoder *decoder) |
| { |
| FLAC__ASSERT(0 != decoder); |
| FLAC__ASSERT(0 != decoder->private_); |
| FLAC__ASSERT(0 != decoder->protected_); |
| FLAC__ASSERT(0 != decoder->private_->stream_decoder); |
| if(decoder->protected_->state != FLAC__SEEKABLE_STREAM_DECODER_UNINITIALIZED) |
| return false; |
| decoder->private_->ignore_stream_info_block = false; |
| decoder->private_->ignore_seek_table_block = false; |
| return FLAC__stream_decoder_set_metadata_respond_all(decoder->private_->stream_decoder); |
| } |
| |
| FLAC_API FLAC__bool FLAC__seekable_stream_decoder_set_metadata_ignore(FLAC__SeekableStreamDecoder *decoder, FLAC__MetadataType type) |
| { |
| FLAC__ASSERT(0 != decoder); |
| FLAC__ASSERT(0 != decoder->private_); |
| FLAC__ASSERT(0 != decoder->protected_); |
| FLAC__ASSERT(0 != decoder->private_->stream_decoder); |
| if(decoder->protected_->state != FLAC__SEEKABLE_STREAM_DECODER_UNINITIALIZED) |
| return false; |
| if(type == FLAC__METADATA_TYPE_STREAMINFO) { |
| decoder->private_->ignore_stream_info_block = true; |
| return true; |
| } |
| else if(type == FLAC__METADATA_TYPE_SEEKTABLE) { |
| decoder->private_->ignore_seek_table_block = true; |
| return true; |
| } |
| else |
| return FLAC__stream_decoder_set_metadata_ignore(decoder->private_->stream_decoder, type); |
| } |
| |
| FLAC_API FLAC__bool FLAC__seekable_stream_decoder_set_metadata_ignore_application(FLAC__SeekableStreamDecoder *decoder, const FLAC__byte id[4]) |
| { |
| FLAC__ASSERT(0 != decoder); |
| FLAC__ASSERT(0 != decoder->private_); |
| FLAC__ASSERT(0 != decoder->protected_); |
| FLAC__ASSERT(0 != decoder->private_->stream_decoder); |
| if(decoder->protected_->state != FLAC__SEEKABLE_STREAM_DECODER_UNINITIALIZED) |
| return false; |
| return FLAC__stream_decoder_set_metadata_ignore_application(decoder->private_->stream_decoder, id); |
| } |
| |
| FLAC_API FLAC__bool FLAC__seekable_stream_decoder_set_metadata_ignore_all(FLAC__SeekableStreamDecoder *decoder) |
| { |
| FLAC__ASSERT(0 != decoder); |
| FLAC__ASSERT(0 != decoder->private_); |
| FLAC__ASSERT(0 != decoder->protected_); |
| FLAC__ASSERT(0 != decoder->private_->stream_decoder); |
| if(decoder->protected_->state != FLAC__SEEKABLE_STREAM_DECODER_UNINITIALIZED) |
| return false; |
| decoder->private_->ignore_stream_info_block = true; |
| decoder->private_->ignore_seek_table_block = true; |
| return |
| FLAC__stream_decoder_set_metadata_ignore_all(decoder->private_->stream_decoder) && |
| FLAC__stream_decoder_set_metadata_respond(decoder->private_->stream_decoder, FLAC__METADATA_TYPE_STREAMINFO) && |
| FLAC__stream_decoder_set_metadata_respond(decoder->private_->stream_decoder, FLAC__METADATA_TYPE_SEEKTABLE); |
| } |
| |
| FLAC_API FLAC__SeekableStreamDecoderState FLAC__seekable_stream_decoder_get_state(const FLAC__SeekableStreamDecoder *decoder) |
| { |
| FLAC__ASSERT(0 != decoder); |
| FLAC__ASSERT(0 != decoder->protected_); |
| return decoder->protected_->state; |
| } |
| |
| FLAC_API FLAC__StreamDecoderState FLAC__seekable_stream_decoder_get_stream_decoder_state(const FLAC__SeekableStreamDecoder *decoder) |
| { |
| FLAC__ASSERT(0 != decoder); |
| FLAC__ASSERT(0 != decoder->private_); |
| return FLAC__stream_decoder_get_state(decoder->private_->stream_decoder); |
| } |
| |
| FLAC_API const char *FLAC__seekable_stream_decoder_get_resolved_state_string(const FLAC__SeekableStreamDecoder *decoder) |
| { |
| if(decoder->protected_->state != FLAC__SEEKABLE_STREAM_DECODER_STREAM_DECODER_ERROR) |
| return FLAC__SeekableStreamDecoderStateString[decoder->protected_->state]; |
| else |
| return FLAC__stream_decoder_get_resolved_state_string(decoder->private_->stream_decoder); |
| } |
| |
| FLAC_API FLAC__bool FLAC__seekable_stream_decoder_get_md5_checking(const FLAC__SeekableStreamDecoder *decoder) |
| { |
| FLAC__ASSERT(0 != decoder); |
| FLAC__ASSERT(0 != decoder->protected_); |
| return decoder->protected_->md5_checking; |
| } |
| |
| FLAC_API unsigned FLAC__seekable_stream_decoder_get_channels(const FLAC__SeekableStreamDecoder *decoder) |
| { |
| FLAC__ASSERT(0 != decoder); |
| FLAC__ASSERT(0 != decoder->private_); |
| return FLAC__stream_decoder_get_channels(decoder->private_->stream_decoder); |
| } |
| |
| FLAC_API FLAC__ChannelAssignment FLAC__seekable_stream_decoder_get_channel_assignment(const FLAC__SeekableStreamDecoder *decoder) |
| { |
| FLAC__ASSERT(0 != decoder); |
| FLAC__ASSERT(0 != decoder->private_); |
| return FLAC__stream_decoder_get_channel_assignment(decoder->private_->stream_decoder); |
| } |
| |
| FLAC_API unsigned FLAC__seekable_stream_decoder_get_bits_per_sample(const FLAC__SeekableStreamDecoder *decoder) |
| { |
| FLAC__ASSERT(0 != decoder); |
| FLAC__ASSERT(0 != decoder->private_); |
| return FLAC__stream_decoder_get_bits_per_sample(decoder->private_->stream_decoder); |
| } |
| |
| FLAC_API unsigned FLAC__seekable_stream_decoder_get_sample_rate(const FLAC__SeekableStreamDecoder *decoder) |
| { |
| FLAC__ASSERT(0 != decoder); |
| FLAC__ASSERT(0 != decoder->private_); |
| return FLAC__stream_decoder_get_sample_rate(decoder->private_->stream_decoder); |
| } |
| |
| FLAC_API unsigned FLAC__seekable_stream_decoder_get_blocksize(const FLAC__SeekableStreamDecoder *decoder) |
| { |
| FLAC__ASSERT(0 != decoder); |
| FLAC__ASSERT(0 != decoder->private_); |
| return FLAC__stream_decoder_get_blocksize(decoder->private_->stream_decoder); |
| } |
| |
| FLAC_API FLAC__bool FLAC__seekable_stream_decoder_get_decode_position(const FLAC__SeekableStreamDecoder *decoder, FLAC__uint64 *position) |
| { |
| FLAC__ASSERT(0 != decoder); |
| FLAC__ASSERT(0 != decoder->private_); |
| FLAC__ASSERT(0 != position); |
| |
| if(decoder->private_->tell_callback(decoder, position, decoder->private_->client_data) != FLAC__SEEKABLE_STREAM_DECODER_TELL_STATUS_OK) |
| return false; |
| FLAC__ASSERT(*position >= FLAC__stream_decoder_get_input_bytes_unconsumed(decoder->private_->stream_decoder)); |
| *position -= FLAC__stream_decoder_get_input_bytes_unconsumed(decoder->private_->stream_decoder); |
| return true; |
| } |
| |
| FLAC_API FLAC__bool FLAC__seekable_stream_decoder_flush(FLAC__SeekableStreamDecoder *decoder) |
| { |
| FLAC__ASSERT(0 != decoder); |
| FLAC__ASSERT(0 != decoder->private_); |
| FLAC__ASSERT(0 != decoder->protected_); |
| |
| decoder->private_->do_md5_checking = false; |
| |
| if(!FLAC__stream_decoder_flush(decoder->private_->stream_decoder)) { |
| decoder->protected_->state = FLAC__SEEKABLE_STREAM_DECODER_STREAM_DECODER_ERROR; |
| return false; |
| } |
| |
| decoder->protected_->state = FLAC__SEEKABLE_STREAM_DECODER_OK; |
| |
| return true; |
| } |
| |
| FLAC_API FLAC__bool FLAC__seekable_stream_decoder_reset(FLAC__SeekableStreamDecoder *decoder) |
| { |
| FLAC__ASSERT(0 != decoder); |
| FLAC__ASSERT(0 != decoder->private_); |
| FLAC__ASSERT(0 != decoder->protected_); |
| |
| if(!FLAC__seekable_stream_decoder_flush(decoder)) { |
| decoder->protected_->state = FLAC__SEEKABLE_STREAM_DECODER_STREAM_DECODER_ERROR; |
| return false; |
| } |
| |
| if(!FLAC__stream_decoder_reset(decoder->private_->stream_decoder)) { |
| decoder->protected_->state = FLAC__SEEKABLE_STREAM_DECODER_STREAM_DECODER_ERROR; |
| return false; |
| } |
| |
| decoder->private_->seek_table = 0; |
| |
| decoder->private_->do_md5_checking = decoder->protected_->md5_checking; |
| |
| /* 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 always init the context here and finalize it in |
| * FLAC__seekable_stream_decoder_finish() to make sure things are always |
| * cleaned up properly. |
| */ |
| FLAC__MD5Init(&decoder->private_->md5context); |
| |
| decoder->protected_->state = FLAC__SEEKABLE_STREAM_DECODER_OK; |
| |
| return true; |
| } |
| |
| FLAC_API FLAC__bool FLAC__seekable_stream_decoder_process_single(FLAC__SeekableStreamDecoder *decoder) |
| { |
| FLAC__bool ret; |
| FLAC__ASSERT(0 != decoder); |
| |
| if(decoder->private_->stream_decoder->protected_->state == FLAC__STREAM_DECODER_END_OF_STREAM) |
| decoder->protected_->state = FLAC__SEEKABLE_STREAM_DECODER_END_OF_STREAM; |
| |
| if(decoder->protected_->state == FLAC__SEEKABLE_STREAM_DECODER_END_OF_STREAM) |
| return true; |
| |
| FLAC__ASSERT(decoder->protected_->state == FLAC__SEEKABLE_STREAM_DECODER_OK); |
| |
| ret = FLAC__stream_decoder_process_single(decoder->private_->stream_decoder); |
| if(!ret) |
| decoder->protected_->state = FLAC__SEEKABLE_STREAM_DECODER_STREAM_DECODER_ERROR; |
| |
| return ret; |
| } |
| |
| FLAC_API FLAC__bool FLAC__seekable_stream_decoder_process_until_end_of_metadata(FLAC__SeekableStreamDecoder *decoder) |
| { |
| FLAC__bool ret; |
| FLAC__ASSERT(0 != decoder); |
| |
| if(decoder->private_->stream_decoder->protected_->state == FLAC__STREAM_DECODER_END_OF_STREAM) |
| decoder->protected_->state = FLAC__SEEKABLE_STREAM_DECODER_END_OF_STREAM; |
| |
| if(decoder->protected_->state == FLAC__SEEKABLE_STREAM_DECODER_END_OF_STREAM) |
| return true; |
| |
| FLAC__ASSERT(decoder->protected_->state == FLAC__SEEKABLE_STREAM_DECODER_OK); |
| |
| ret = FLAC__stream_decoder_process_until_end_of_metadata(decoder->private_->stream_decoder); |
| if(!ret) |
| decoder->protected_->state = FLAC__SEEKABLE_STREAM_DECODER_STREAM_DECODER_ERROR; |
| |
| return ret; |
| } |
| |
| FLAC_API FLAC__bool FLAC__seekable_stream_decoder_process_until_end_of_stream(FLAC__SeekableStreamDecoder *decoder) |
| { |
| FLAC__bool ret; |
| FLAC__ASSERT(0 != decoder); |
| |
| if(decoder->private_->stream_decoder->protected_->state == FLAC__STREAM_DECODER_END_OF_STREAM) |
| decoder->protected_->state = FLAC__SEEKABLE_STREAM_DECODER_END_OF_STREAM; |
| |
| if(decoder->protected_->state == FLAC__SEEKABLE_STREAM_DECODER_END_OF_STREAM) |
| return true; |
| |
| FLAC__ASSERT(decoder->protected_->state == FLAC__SEEKABLE_STREAM_DECODER_OK); |
| |
| ret = FLAC__stream_decoder_process_until_end_of_stream(decoder->private_->stream_decoder); |
| if(!ret) |
| decoder->protected_->state = FLAC__SEEKABLE_STREAM_DECODER_STREAM_DECODER_ERROR; |
| |
| return ret; |
| } |
| |
| FLAC_API FLAC__bool FLAC__seekable_stream_decoder_skip_single_frame(FLAC__SeekableStreamDecoder *decoder) |
| { |
| FLAC__bool ret; |
| FLAC__ASSERT(0 != decoder); |
| |
| if(decoder->private_->stream_decoder->protected_->state == FLAC__STREAM_DECODER_END_OF_STREAM) |
| decoder->protected_->state = FLAC__SEEKABLE_STREAM_DECODER_END_OF_STREAM; |
| |
| if(decoder->protected_->state == FLAC__SEEKABLE_STREAM_DECODER_END_OF_STREAM) |
| return true; |
| |
| FLAC__ASSERT(decoder->protected_->state == FLAC__SEEKABLE_STREAM_DECODER_OK); |
| |
| ret = FLAC__stream_decoder_skip_single_frame(decoder->private_->stream_decoder); |
| if(!ret) |
| decoder->protected_->state = FLAC__SEEKABLE_STREAM_DECODER_STREAM_DECODER_ERROR; |
| |
| return ret; |
| } |
| |
| FLAC_API FLAC__bool FLAC__seekable_stream_decoder_seek_absolute(FLAC__SeekableStreamDecoder *decoder, FLAC__uint64 sample) |
| { |
| FLAC__uint64 length; |
| |
| FLAC__ASSERT(0 != decoder); |
| FLAC__ASSERT(decoder->protected_->state == FLAC__SEEKABLE_STREAM_DECODER_OK || decoder->protected_->state == FLAC__SEEKABLE_STREAM_DECODER_END_OF_STREAM); |
| |
| decoder->protected_->state = FLAC__SEEKABLE_STREAM_DECODER_SEEKING; |
| |
| /* turn off md5 checking if a seek is attempted */ |
| decoder->private_->do_md5_checking = false; |
| |
| if(!FLAC__stream_decoder_reset(decoder->private_->stream_decoder)) { |
| decoder->protected_->state = FLAC__SEEKABLE_STREAM_DECODER_STREAM_DECODER_ERROR; |
| return false; |
| } |
| /* get the file length */ |
| if(decoder->private_->length_callback(decoder, &length, decoder->private_->client_data) != FLAC__SEEKABLE_STREAM_DECODER_LENGTH_STATUS_OK) { |
| decoder->protected_->state = FLAC__SEEKABLE_STREAM_DECODER_SEEK_ERROR; |
| return false; |
| } |
| /* rewind */ |
| if(decoder->private_->seek_callback(decoder, 0, decoder->private_->client_data) != FLAC__SEEKABLE_STREAM_DECODER_SEEK_STATUS_OK) { |
| decoder->protected_->state = FLAC__SEEKABLE_STREAM_DECODER_SEEK_ERROR; |
| return false; |
| } |
| if(!FLAC__stream_decoder_process_until_end_of_metadata(decoder->private_->stream_decoder)) { |
| decoder->protected_->state = FLAC__SEEKABLE_STREAM_DECODER_STREAM_DECODER_ERROR; |
| return false; |
| } |
| if(decoder->private_->stream_info.total_samples > 0 && sample >= decoder->private_->stream_info.total_samples) { |
| decoder->protected_->state = FLAC__SEEKABLE_STREAM_DECODER_SEEK_ERROR; |
| return false; |
| } |
| |
| return seek_to_absolute_sample_(decoder, length, sample); |
| } |
| |
| /*********************************************************************** |
| * |
| * Private class methods |
| * |
| ***********************************************************************/ |
| |
| void set_defaults_(FLAC__SeekableStreamDecoder *decoder) |
| { |
| 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; |
| /* WATCHOUT: these should match the default behavior of FLAC__StreamDecoder */ |
| decoder->private_->ignore_stream_info_block = false; |
| decoder->private_->ignore_seek_table_block = true; |
| |
| decoder->protected_->md5_checking = false; |
| } |
| |
| FLAC__StreamDecoderReadStatus read_callback_(const FLAC__StreamDecoder *decoder, FLAC__byte buffer[], unsigned *bytes, void *client_data) |
| { |
| FLAC__SeekableStreamDecoder *seekable_stream_decoder = (FLAC__SeekableStreamDecoder *)client_data; |
| (void)decoder; |
| if(seekable_stream_decoder->private_->eof_callback(seekable_stream_decoder, seekable_stream_decoder->private_->client_data)) { |
| *bytes = 0; |
| #if 0 |
| /*@@@@@@ verify that this is not needed */ |
| seekable_stream_decoder->protected_->state = FLAC__SEEKABLE_STREAM_DECODER_END_OF_STREAM; |
| #endif |
| return FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM; |
| } |
| else if(*bytes > 0) { |
| if(seekable_stream_decoder->private_->read_callback(seekable_stream_decoder, buffer, bytes, seekable_stream_decoder->private_->client_data) != FLAC__SEEKABLE_STREAM_DECODER_READ_STATUS_OK) { |
| seekable_stream_decoder->protected_->state = FLAC__SEEKABLE_STREAM_DECODER_READ_ERROR; |
| return FLAC__STREAM_DECODER_READ_STATUS_ABORT; |
| } |
| if(*bytes == 0) { |
| if(seekable_stream_decoder->private_->eof_callback(seekable_stream_decoder, seekable_stream_decoder->private_->client_data)) { |
| #if 0 |
| /*@@@@@@ verify that this is not needed */ |
| seekable_stream_decoder->protected_->state = FLAC__SEEKABLE_STREAM_DECODER_END_OF_STREAM; |
| #endif |
| return FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM; |
| } |
| else |
| return FLAC__STREAM_DECODER_READ_STATUS_CONTINUE; |
| } |
| else { |
| return FLAC__STREAM_DECODER_READ_STATUS_CONTINUE; |
| } |
| } |
| else |
| return FLAC__STREAM_DECODER_READ_STATUS_ABORT; /* abort to avoid a deadlock */ |
| } |
| |
| FLAC__StreamDecoderWriteStatus write_callback_(const FLAC__StreamDecoder *decoder, const FLAC__Frame *frame, const FLAC__int32 * const buffer[], void *client_data) |
| { |
| FLAC__SeekableStreamDecoder *seekable_stream_decoder = (FLAC__SeekableStreamDecoder *)client_data; |
| (void)decoder; |
| |
| if(seekable_stream_decoder->protected_->state == FLAC__SEEKABLE_STREAM_DECODER_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 = seekable_stream_decoder->private_->target_sample; |
| |
| FLAC__ASSERT(frame->header.number_type == FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER); |
| |
| seekable_stream_decoder->private_->last_frame = *frame; /* save the frame */ |
| if(this_frame_sample <= target_sample && target_sample < next_frame_sample) { /* we hit our target frame */ |
| unsigned delta = (unsigned)(target_sample - this_frame_sample); |
| /* kick out of seek mode */ |
| seekable_stream_decoder->protected_->state = FLAC__SEEKABLE_STREAM_DECODER_OK; |
| /* shift out the samples before target_sample */ |
| if(delta > 0) { |
| unsigned channel; |
| const FLAC__int32 *newbuffer[FLAC__MAX_CHANNELS]; |
| for(channel = 0; channel < frame->header.channels; channel++) |
| newbuffer[channel] = buffer[channel] + delta; |
| seekable_stream_decoder->private_->last_frame.header.blocksize -= delta; |
| seekable_stream_decoder->private_->last_frame.header.number.sample_number += (FLAC__uint64)delta; |
| /* write the relevant samples */ |
| return seekable_stream_decoder->private_->write_callback(seekable_stream_decoder, &seekable_stream_decoder->private_->last_frame, newbuffer, seekable_stream_decoder->private_->client_data); |
| } |
| else { |
| /* write the relevant samples */ |
| return seekable_stream_decoder->private_->write_callback(seekable_stream_decoder, frame, buffer, seekable_stream_decoder->private_->client_data); |
| } |
| } |
| else { |
| return FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE; |
| } |
| } |
| else { |
| if(seekable_stream_decoder->private_->do_md5_checking) { |
| if(!FLAC__MD5Accumulate(&seekable_stream_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 seekable_stream_decoder->private_->write_callback(seekable_stream_decoder, frame, buffer, seekable_stream_decoder->private_->client_data); |
| } |
| } |
| |
| void metadata_callback_(const FLAC__StreamDecoder *decoder, const FLAC__StreamMetadata *metadata, void *client_data) |
| { |
| FLAC__SeekableStreamDecoder *seekable_stream_decoder = (FLAC__SeekableStreamDecoder *)client_data; |
| (void)decoder; |
| |
| if(metadata->type == FLAC__METADATA_TYPE_STREAMINFO) { |
| seekable_stream_decoder->private_->stream_info = metadata->data.stream_info; |
| /* save the MD5 signature for comparison later */ |
| memcpy(seekable_stream_decoder->private_->stored_md5sum, metadata->data.stream_info.md5sum, 16); |
| if(0 == memcmp(seekable_stream_decoder->private_->stored_md5sum, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0", 16)) |
| seekable_stream_decoder->private_->do_md5_checking = false; |
| } |
| else if(metadata->type == FLAC__METADATA_TYPE_SEEKTABLE) { |
| seekable_stream_decoder->private_->seek_table = &metadata->data.seek_table; |
| } |
| |
| if(seekable_stream_decoder->protected_->state != FLAC__SEEKABLE_STREAM_DECODER_SEEKING) { |
| FLAC__bool ignore_block = false; |
| if(metadata->type == FLAC__METADATA_TYPE_STREAMINFO && seekable_stream_decoder->private_->ignore_stream_info_block) |
| ignore_block = true; |
| else if(metadata->type == FLAC__METADATA_TYPE_SEEKTABLE && seekable_stream_decoder->private_->ignore_seek_table_block) |
| ignore_block = true; |
| if(!ignore_block) |
| seekable_stream_decoder->private_->metadata_callback(seekable_stream_decoder, metadata, seekable_stream_decoder->private_->client_data); |
| } |
| } |
| |
| void error_callback_(const FLAC__StreamDecoder *decoder, FLAC__StreamDecoderErrorStatus status, void *client_data) |
| { |
| FLAC__SeekableStreamDecoder *seekable_stream_decoder = (FLAC__SeekableStreamDecoder *)client_data; |
| (void)decoder; |
| |
| if(seekable_stream_decoder->protected_->state != FLAC__SEEKABLE_STREAM_DECODER_SEEKING) |
| seekable_stream_decoder->private_->error_callback(seekable_stream_decoder, status, seekable_stream_decoder->private_->client_data); |
| } |
| |
| FLAC__bool seek_to_absolute_sample_(FLAC__SeekableStreamDecoder *decoder, FLAC__uint64 stream_length, FLAC__uint64 target_sample) |
| { |
| FLAC__uint64 first_frame_offset, lower_bound, upper_bound; |
| FLAC__int64 pos = -1, last_pos = -1; |
| int i, lower_seek_point = -1, upper_seek_point = -1; |
| unsigned approx_bytes_per_frame; |
| FLAC__uint64 last_frame_sample = FLAC__U64L(0xffffffffffffffff); |
| FLAC__bool needs_seek; |
| const FLAC__uint64 total_samples = decoder->private_->stream_info.total_samples; |
| const unsigned min_blocksize = decoder->private_->stream_info.min_blocksize; |
| const unsigned max_blocksize = decoder->private_->stream_info.max_blocksize; |
| const unsigned max_framesize = decoder->private_->stream_info.max_framesize; |
| const unsigned channels = FLAC__seekable_stream_decoder_get_channels(decoder); |
| const unsigned bps = FLAC__seekable_stream_decoder_get_bits_per_sample(decoder); |
| |
| /* we are just guessing here, but we want to guess high, not low */ |
| if(max_framesize > 0) { |
| approx_bytes_per_frame = max_framesize; |
| } |
| /* |
| * 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 calulation */ |
| approx_bytes_per_frame = min_blocksize * channels * bps/8 + 64; |
| } |
| else |
| approx_bytes_per_frame = 4608 * channels * bps/8 + 64; |
| |
| /* |
| * The decode position is currently at the first frame since we |
| * rewound and processed metadata. |
| */ |
| if(!FLAC__seekable_stream_decoder_get_decode_position(decoder, &first_frame_offset)) { |
| decoder->protected_->state = FLAC__SEEKABLE_STREAM_DECODER_SEEK_ERROR; |
| return false; |
| } |
| |
| /* |
| * 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 and last frames. |
| */ |
| lower_bound = first_frame_offset; |
| |
| /* calc the upper_bound, beyond which we never want to seek */ |
| if(max_framesize > 0) |
| upper_bound = stream_length - (max_framesize + 128 + 2); /* 128 for a possible ID3V1 tag, 2 for indexing differences */ |
| else |
| upper_bound = stream_length - ((channels * bps * FLAC__MAX_BLOCK_SIZE) / 8 + 128 + 2); |
| |
| /* |
| * 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. |
| */ |
| if(0 != decoder->private_->seek_table) { |
| /* find the closest seek point <= target_sample, if it exists */ |
| for(i = (int)decoder->private_->seek_table->num_points - 1; i >= 0; i--) { |
| if(decoder->private_->seek_table->points[i].sample_number != FLAC__STREAM_METADATA_SEEKPOINT_PLACEHOLDER && decoder->private_->seek_table->points[i].sample_number <= target_sample) |
| break; |
| } |
| if(i >= 0) { /* i.e. we found a suitable seek point... */ |
| lower_bound = first_frame_offset + decoder->private_->seek_table->points[i].stream_offset; |
| lower_seek_point = i; |
| } |
| |
| /* find the closest seek point > target_sample, if it exists */ |
| for(i = 0; i < (int)decoder->private_->seek_table->num_points; i++) { |
| if(decoder->private_->seek_table->points[i].sample_number != FLAC__STREAM_METADATA_SEEKPOINT_PLACEHOLDER && decoder->private_->seek_table->points[i].sample_number > target_sample) |
| break; |
| } |
| if(i < (int)decoder->private_->seek_table->num_points) { /* i.e. we found a suitable seek point... */ |
| upper_bound = first_frame_offset + decoder->private_->seek_table->points[i].stream_offset; |
| upper_seek_point = i; |
| } |
| } |
| |
| /* |
| * Now guess at where within those bounds our target |
| * sample will be. |
| */ |
| if(lower_seek_point >= 0) { |
| /* first see if our sample is within a few frames of the lower seekpoint */ |
| if(decoder->private_->seek_table->points[lower_seek_point].sample_number <= target_sample && target_sample < decoder->private_->seek_table->points[lower_seek_point].sample_number + (decoder->private_->seek_table->points[lower_seek_point].frame_samples * 4)) { |
| pos = (FLAC__int64)lower_bound; |
| } |
| else if(upper_seek_point >= 0) { |
| const FLAC__uint64 target_offset = target_sample - decoder->private_->seek_table->points[lower_seek_point].sample_number; |
| const FLAC__uint64 range_samples = decoder->private_->seek_table->points[upper_seek_point].sample_number - decoder->private_->seek_table->points[lower_seek_point].sample_number; |
| const FLAC__uint64 range_bytes = (upper_bound>lower_bound? upper_bound - lower_bound - 1 : 0); |
| #ifndef FLAC__INTEGER_ONLY_LIBRARY |
| #if defined _MSC_VER || defined __MINGW32__ |
| /* with MSVC you have to spoon feed it the casting */ |
| pos = (FLAC__int64)lower_bound + (FLAC__int64)(((FLAC__double)(FLAC__int64)target_offset / (FLAC__double)(FLAC__int64)range_samples) * (FLAC__double)(FLAC__int64)(range_bytes-1)) - approx_bytes_per_frame; |
| #else |
| pos = (FLAC__int64)lower_bound + (FLAC__int64)(((FLAC__double)target_offset / (FLAC__double)range_samples) * (FLAC__double)range_bytes) - approx_bytes_per_frame; |
| #endif |
| #else |
| /* a little less accurate: */ |
| if (range_bytes <= 0xffffffff) |
| pos = (FLAC__int64)lower_bound + (FLAC__int64)((target_offset * range_bytes) / range_samples) - approx_bytes_per_frame; |
| else /* @@@ WATCHOUT, ~2TB limit */ |
| pos = (FLAC__int64)lower_bound + (FLAC__int64)(((target_offset>>8) * (range_bytes>>8)) / (range_samples>>16)) - approx_bytes_per_frame; |
| #endif |
| } |
| } |
| |
| /* |
| * If there's no seek table, we need to use the metadata (if we |
| * have it) and the filelength to estimate the position of the |
| * frame with the correct sample. |
| */ |
| if(pos < 0 && total_samples > 0) { |
| /* |
| * For max accuracy we should be using |
| * (stream_length-first_frame_offset-1) in the divisor, but the |
| * difference is trivial and (stream_length-first_frame_offset) |
| * has no chance of underflow. |
| */ |
| #ifndef FLAC__INTEGER_ONLY_LIBRARY |
| #if defined _MSC_VER || defined __MINGW32__ |
| /* with VC++ you have to spoon feed it the casting */ |
| pos = (FLAC__int64)first_frame_offset + (FLAC__int64)(((FLAC__double)(FLAC__int64)target_sample / (FLAC__double)(FLAC__int64)total_samples) * (FLAC__double)(FLAC__int64)(stream_length-first_frame_offset)) - approx_bytes_per_frame; |
| #else |
| pos = (FLAC__int64)first_frame_offset + (FLAC__int64)(((FLAC__double)target_sample / (FLAC__double)total_samples) * (FLAC__double)(stream_length-first_frame_offset)) - approx_bytes_per_frame; |
| #endif |
| #else |
| /* a little less accurate: */ |
| if (stream_length < 0xffffffff) |
| pos = (FLAC__int64)first_frame_offset + (FLAC__int64)((target_sample * (stream_length-first_frame_offset)) / total_samples) - approx_bytes_per_frame; |
| else /* @@@ WATCHOUT, ~2TB limit */ |
| pos = (FLAC__int64)first_frame_offset + (FLAC__int64)(((target_sample>>8) * ((stream_length-first_frame_offset)>>8)) / (total_samples>>16)) - approx_bytes_per_frame; |
| #endif |
| } |
| |
| /* |
| * If there's no seek table and total_samples is unknown, we |
| * don't even bother trying to figure out a target, we just use |
| * our current position. |
| */ |
| if(pos < 0) { |
| FLAC__uint64 upos; |
| if(decoder->private_->tell_callback(decoder, &upos, decoder->private_->client_data) != FLAC__SEEKABLE_STREAM_DECODER_TELL_STATUS_OK) { |
| decoder->protected_->state = FLAC__SEEKABLE_STREAM_DECODER_SEEK_ERROR; |
| return false; |
| } |
| pos = (FLAC__int64)upos; |
| needs_seek = false; |
| } |
| else |
| needs_seek = true; |
| |
| /* clip the position to the bounds, lower bound takes precedence */ |
| if(pos >= (FLAC__int64)upper_bound) { |
| pos = (FLAC__int64)upper_bound-1; |
| needs_seek = true; |
| } |
| if(pos < (FLAC__int64)lower_bound) { |
| pos = (FLAC__int64)lower_bound; |
| needs_seek = true; |
| } |
| |
| decoder->private_->target_sample = target_sample; |
| while(1) { |
| if(needs_seek) { |
| if(decoder->private_->seek_callback(decoder, (FLAC__uint64)pos, decoder->private_->client_data) != FLAC__SEEKABLE_STREAM_DECODER_SEEK_STATUS_OK) { |
| decoder->protected_->state = FLAC__SEEKABLE_STREAM_DECODER_SEEK_ERROR; |
| return false; |
| } |
| if(!FLAC__stream_decoder_flush(decoder->private_->stream_decoder)) { |
| decoder->protected_->state = FLAC__SEEKABLE_STREAM_DECODER_STREAM_DECODER_ERROR; |
| return false; |
| } |
| } |
| /* Now we need to get a frame. 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, FLAC__stream_decoder_process_single() will |
| * return false and the state will be |
| * FLAC__STREAM_DECODER_UNPARSEABLE_STREAM. 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 |
| * several "unparseable" errors in a row before bailing out. |
| */ |
| { |
| unsigned unparseable_count; |
| FLAC__bool got_a_frame = false; |
| for (unparseable_count = 0; !got_a_frame && unparseable_count < 10; unparseable_count++) { |
| if(FLAC__stream_decoder_process_single(decoder->private_->stream_decoder)) |
| got_a_frame = true; |
| else if(decoder->private_->stream_decoder->protected_->state == FLAC__STREAM_DECODER_UNPARSEABLE_STREAM) |
| /* try again. we don't want to flush the decoder since that clears the bitbuffer */ |
| decoder->private_->stream_decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC; |
| else /* it's a real error */ |
| break; |
| } |
| if (!got_a_frame) { |
| decoder->protected_->state = FLAC__SEEKABLE_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__SEEKABLE_STREAM_DECODER_END_OF_STREAM so we need to check for that also */ |
| if(decoder->protected_->state != FLAC__SEEKABLE_STREAM_DECODER_SEEKING && decoder->protected_->state != FLAC__SEEKABLE_STREAM_DECODER_END_OF_STREAM) { |
| break; |
| } |
| else { /* we need to narrow the search */ |
| const FLAC__uint64 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(this_frame_sample == last_frame_sample && pos < last_pos) { |
| /* our last move backwards wasn't big enough, double it */ |
| pos -= (last_pos - pos); |
| needs_seek = true; |
| } |
| else { |
| if(target_sample < this_frame_sample) { |
| last_pos = pos; |
| approx_bytes_per_frame = decoder->private_->last_frame.header.blocksize * channels * bps/8 + 64; |
| pos -= approx_bytes_per_frame; |
| needs_seek = true; |
| } |
| else { /* target_sample >= this_frame_sample + this frame's blocksize */ |
| FLAC__uint64 upos; |
| if(decoder->private_->tell_callback(decoder, &upos, decoder->private_->client_data) != FLAC__SEEKABLE_STREAM_DECODER_TELL_STATUS_OK) { |
| decoder->protected_->state = FLAC__SEEKABLE_STREAM_DECODER_SEEK_ERROR; |
| return false; |
| } |
| last_pos = pos; |
| pos = (FLAC__int64)upos; |
| pos -= FLAC__stream_decoder_get_input_bytes_unconsumed(decoder->private_->stream_decoder); |
| needs_seek = false; |
| /* |
| * if we haven't hit the target frame yet and our position hasn't changed, |
| * it means we're at the end of the stream and the seek target does not exist. |
| */ |
| if(last_pos == pos) { |
| decoder->protected_->state = FLAC__SEEKABLE_STREAM_DECODER_SEEK_ERROR; |
| return false; |
| } |
| } |
| } |
| if(pos < (FLAC__int64)lower_bound) |
| pos = (FLAC__int64)lower_bound; |
| last_frame_sample = this_frame_sample; |
| } |
| } |
| |
| return true; |
| } |