Mercurial > hg > sv-dependency-builds
diff src/flac-1.2.1/include/FLAC/stream_decoder.h @ 1:05aa0afa9217
Bring in flac, ogg, vorbis
| author | Chris Cannam |
|---|---|
| date | Tue, 19 Mar 2013 17:37:49 +0000 |
| parents | |
| children |
line wrap: on
line diff
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/src/flac-1.2.1/include/FLAC/stream_decoder.h Tue Mar 19 17:37:49 2013 +0000 @@ -0,0 +1,1559 @@ +/* libFLAC - Free Lossless Audio Codec library + * Copyright (C) 2000,2001,2002,2003,2004,2005,2006,2007 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. + */ + +#ifndef FLAC__STREAM_DECODER_H +#define FLAC__STREAM_DECODER_H + +#include <stdio.h> /* for FILE */ +#include "export.h" +#include "format.h" + +#ifdef __cplusplus +extern "C" { +#endif + + +/** \file include/FLAC/stream_decoder.h + * + * \brief + * This module contains the functions which implement the stream + * decoder. + * + * See the detailed documentation in the + * \link flac_stream_decoder stream decoder \endlink module. + */ + +/** \defgroup flac_decoder FLAC/ \*_decoder.h: decoder interfaces + * \ingroup flac + * + * \brief + * This module describes the decoder layers provided by libFLAC. + * + * The stream decoder can be used to decode complete streams either from + * the client via callbacks, or directly from a file, depending on how + * it is initialized. When decoding via callbacks, the client provides + * callbacks for reading FLAC data and writing decoded samples, and + * handling metadata and errors. If the client also supplies seek-related + * callback, the decoder function for sample-accurate seeking within the + * FLAC input is also available. When decoding from a file, the client + * needs only supply a filename or open \c FILE* and write/metadata/error + * callbacks; the rest of the callbacks are supplied internally. For more + * info see the \link flac_stream_decoder stream decoder \endlink module. + */ + +/** \defgroup flac_stream_decoder FLAC/stream_decoder.h: stream decoder interface + * \ingroup flac_decoder + * + * \brief + * This module contains the functions which implement the stream + * decoder. + * + * The stream decoder can decode native FLAC, and optionally Ogg FLAC + * (check FLAC_API_SUPPORTS_OGG_FLAC) streams and files. + * + * The basic usage of this decoder is as follows: + * - The program creates an instance of a decoder using + * FLAC__stream_decoder_new(). + * - The program overrides the default settings using + * FLAC__stream_decoder_set_*() functions. + * - The program initializes the instance to validate the settings and + * prepare for decoding using + * - FLAC__stream_decoder_init_stream() or FLAC__stream_decoder_init_FILE() + * or FLAC__stream_decoder_init_file() for native FLAC, + * - FLAC__stream_decoder_init_ogg_stream() or FLAC__stream_decoder_init_ogg_FILE() + * or FLAC__stream_decoder_init_ogg_file() for Ogg FLAC + * - The program calls the FLAC__stream_decoder_process_*() functions + * to decode data, which subsequently calls the callbacks. + * - The program finishes the decoding with FLAC__stream_decoder_finish(), + * which flushes the input and output and resets the decoder to the + * uninitialized state. + * - The instance may be used again or deleted with + * FLAC__stream_decoder_delete(). + * + * In more detail, the program will create a new instance by calling + * FLAC__stream_decoder_new(), then call FLAC__stream_decoder_set_*() + * functions to override the default decoder options, and call + * one of the FLAC__stream_decoder_init_*() functions. + * + * There are three initialization functions for native FLAC, one for + * setting up the decoder to decode FLAC data from the client via + * callbacks, and two for decoding directly from a FLAC file. + * + * For decoding via callbacks, use FLAC__stream_decoder_init_stream(). + * You must also supply several callbacks for handling I/O. Some (like + * seeking) are optional, depending on the capabilities of the input. + * + * For decoding directly from a file, use FLAC__stream_decoder_init_FILE() + * or FLAC__stream_decoder_init_file(). Then you must only supply an open + * \c FILE* or filename and fewer callbacks; the decoder will handle + * the other callbacks internally. + * + * There are three similarly-named init functions for decoding from Ogg + * FLAC streams. Check \c FLAC_API_SUPPORTS_OGG_FLAC to find out if the + * library has been built with Ogg support. + * + * Once the decoder is initialized, your program will call one of several + * functions to start the decoding process: + * + * - FLAC__stream_decoder_process_single() - Tells the decoder to process at + * most one metadata block or audio frame and return, calling either the + * metadata callback or write callback, respectively, once. If the decoder + * loses sync it will return with only the error callback being called. + * - FLAC__stream_decoder_process_until_end_of_metadata() - Tells the decoder + * to process the stream from the current location and stop upon reaching + * the first audio frame. The client will get one metadata, write, or error + * callback per metadata block, audio frame, or sync error, respectively. + * - FLAC__stream_decoder_process_until_end_of_stream() - Tells the decoder + * to process the stream from the current location until the read callback + * returns FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM or + * FLAC__STREAM_DECODER_READ_STATUS_ABORT. The client will get one metadata, + * write, or error callback per metadata block, audio frame, or sync error, + * respectively. + * + * When the decoder has finished decoding (normally or through an abort), + * the instance is finished by calling FLAC__stream_decoder_finish(), which + * ensures the decoder is in the correct state and frees memory. Then the + * instance may be deleted with FLAC__stream_decoder_delete() or initialized + * again to decode another stream. + * + * Seeking is exposed through the FLAC__stream_decoder_seek_absolute() method. + * At any point after the stream decoder has been initialized, the client can + * call this function to seek to an exact sample within the stream. + * Subsequently, the first time the write callback is called it will be + * passed a (possibly partial) block starting at that sample. + * + * If the client cannot seek via the callback interface provided, but still + * has another way of seeking, it can flush the decoder using + * FLAC__stream_decoder_flush() and start feeding data from the new position + * through the read callback. + * + * The stream decoder also provides MD5 signature checking. If this is + * turned on before initialization, FLAC__stream_decoder_finish() will + * report when the decoded MD5 signature does not match the one stored + * in the STREAMINFO block. MD5 checking is automatically turned off + * (until the next FLAC__stream_decoder_reset()) if there is no signature + * in the STREAMINFO block or when a seek is attempted. + * + * The FLAC__stream_decoder_set_metadata_*() functions deserve special + * attention. By default, the decoder only calls the metadata_callback for + * the STREAMINFO block. These functions allow you to tell the decoder + * explicitly which blocks to parse and return via the metadata_callback + * and/or which to skip. Use a FLAC__stream_decoder_set_metadata_respond_all(), + * FLAC__stream_decoder_set_metadata_ignore() ... or FLAC__stream_decoder_set_metadata_ignore_all(), + * FLAC__stream_decoder_set_metadata_respond() ... sequence to exactly specify + * which blocks to return. Remember that metadata blocks can potentially + * be big (for example, cover art) so filtering out the ones you don't + * use can reduce the memory requirements of the decoder. Also note the + * special forms FLAC__stream_decoder_set_metadata_respond_application(id) + * and FLAC__stream_decoder_set_metadata_ignore_application(id) for + * filtering APPLICATION blocks based on the application ID. + * + * STREAMINFO and SEEKTABLE blocks are always parsed and used internally, but + * they still can legally be filtered from the metadata_callback. + * + * \note + * The "set" functions may only be called when the decoder is in the + * state FLAC__STREAM_DECODER_UNINITIALIZED, i.e. after + * FLAC__stream_decoder_new() or FLAC__stream_decoder_finish(), but + * before FLAC__stream_decoder_init_*(). If this is the case they will + * return \c true, otherwise \c false. + * + * \note + * FLAC__stream_decoder_finish() resets all settings to the constructor + * defaults, including the callbacks. + * + * \{ + */ + + +/** State values for a FLAC__StreamDecoder + * + * The decoder's state can be obtained by calling FLAC__stream_decoder_get_state(). + */ +typedef enum { + + FLAC__STREAM_DECODER_SEARCH_FOR_METADATA = 0, + /**< The decoder is ready to search for metadata. */ + + FLAC__STREAM_DECODER_READ_METADATA, + /**< The decoder is ready to or is in the process of reading metadata. */ + + FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC, + /**< The decoder is ready to or is in the process of searching for the + * frame sync code. + */ + + FLAC__STREAM_DECODER_READ_FRAME, + /**< The decoder is ready to or is in the process of reading a frame. */ + + FLAC__STREAM_DECODER_END_OF_STREAM, + /**< The decoder has reached the end of the stream. */ + + FLAC__STREAM_DECODER_OGG_ERROR, + /**< An error occurred in the underlying Ogg layer. */ + + FLAC__STREAM_DECODER_SEEK_ERROR, + /**< An error occurred while seeking. The decoder must be flushed + * with FLAC__stream_decoder_flush() or reset with + * FLAC__stream_decoder_reset() before decoding can continue. + */ + + FLAC__STREAM_DECODER_ABORTED, + /**< The decoder was aborted by the read callback. */ + + FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR, + /**< An error occurred allocating memory. The decoder is in an invalid + * state and can no longer be used. + */ + + FLAC__STREAM_DECODER_UNINITIALIZED + /**< The decoder is in the uninitialized state; one of the + * FLAC__stream_decoder_init_*() functions must be called before samples + * can be processed. + */ + +} FLAC__StreamDecoderState; + +/** Maps a FLAC__StreamDecoderState to a C string. + * + * Using a FLAC__StreamDecoderState as the index to this array + * will give the string equivalent. The contents should not be modified. + */ +extern FLAC_API const char * const FLAC__StreamDecoderStateString[]; + + +/** Possible return values for the FLAC__stream_decoder_init_*() functions. + */ +typedef enum { + + FLAC__STREAM_DECODER_INIT_STATUS_OK = 0, + /**< Initialization was successful. */ + + FLAC__STREAM_DECODER_INIT_STATUS_UNSUPPORTED_CONTAINER, + /**< The library was not compiled with support for the given container + * format. + */ + + FLAC__STREAM_DECODER_INIT_STATUS_INVALID_CALLBACKS, + /**< A required callback was not supplied. */ + + FLAC__STREAM_DECODER_INIT_STATUS_MEMORY_ALLOCATION_ERROR, + /**< An error occurred allocating memory. */ + + FLAC__STREAM_DECODER_INIT_STATUS_ERROR_OPENING_FILE, + /**< fopen() failed in FLAC__stream_decoder_init_file() or + * FLAC__stream_decoder_init_ogg_file(). */ + + FLAC__STREAM_DECODER_INIT_STATUS_ALREADY_INITIALIZED + /**< FLAC__stream_decoder_init_*() was called when the decoder was + * already initialized, usually because + * FLAC__stream_decoder_finish() was not called. + */ + +} FLAC__StreamDecoderInitStatus; + +/** Maps a FLAC__StreamDecoderInitStatus to a C string. + * + * Using a FLAC__StreamDecoderInitStatus as the index to this array + * will give the string equivalent. The contents should not be modified. + */ +extern FLAC_API const char * const FLAC__StreamDecoderInitStatusString[]; + + +/** Return values for the FLAC__StreamDecoder read callback. + */ +typedef enum { + + FLAC__STREAM_DECODER_READ_STATUS_CONTINUE, + /**< The read was OK and decoding can continue. */ + + FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM, + /**< The read was attempted while at the end of the stream. Note that + * the client must only return this value when the read callback was + * called when already at the end of the stream. Otherwise, if the read + * itself moves to the end of the stream, the client should still return + * the data and \c FLAC__STREAM_DECODER_READ_STATUS_CONTINUE, and then on + * the next read callback it should return + * \c FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM with a byte count + * of \c 0. + */ + + FLAC__STREAM_DECODER_READ_STATUS_ABORT + /**< An unrecoverable error occurred. The decoder will return from the process call. */ + +} FLAC__StreamDecoderReadStatus; + +/** Maps a FLAC__StreamDecoderReadStatus to a C string. + * + * Using a FLAC__StreamDecoderReadStatus as the index to this array + * will give the string equivalent. The contents should not be modified. + */ +extern FLAC_API const char * const FLAC__StreamDecoderReadStatusString[]; + + +/** Return values for the FLAC__StreamDecoder seek callback. + */ +typedef enum { + + FLAC__STREAM_DECODER_SEEK_STATUS_OK, + /**< The seek was OK and decoding can continue. */ + + FLAC__STREAM_DECODER_SEEK_STATUS_ERROR, + /**< An unrecoverable error occurred. The decoder will return from the process call. */ + + FLAC__STREAM_DECODER_SEEK_STATUS_UNSUPPORTED + /**< Client does not support seeking. */ + +} FLAC__StreamDecoderSeekStatus; + +/** Maps a FLAC__StreamDecoderSeekStatus to a C string. + * + * Using a FLAC__StreamDecoderSeekStatus as the index to this array + * will give the string equivalent. The contents should not be modified. + */ +extern FLAC_API const char * const FLAC__StreamDecoderSeekStatusString[]; + + +/** Return values for the FLAC__StreamDecoder tell callback. + */ +typedef enum { + + FLAC__STREAM_DECODER_TELL_STATUS_OK, + /**< The tell was OK and decoding can continue. */ + + FLAC__STREAM_DECODER_TELL_STATUS_ERROR, + /**< An unrecoverable error occurred. The decoder will return from the process call. */ + + FLAC__STREAM_DECODER_TELL_STATUS_UNSUPPORTED + /**< Client does not support telling the position. */ + +} FLAC__StreamDecoderTellStatus; + +/** Maps a FLAC__StreamDecoderTellStatus to a C string. + * + * Using a FLAC__StreamDecoderTellStatus as the index to this array + * will give the string equivalent. The contents should not be modified. + */ +extern FLAC_API const char * const FLAC__StreamDecoderTellStatusString[]; + + +/** Return values for the FLAC__StreamDecoder length callback. + */ +typedef enum { + + FLAC__STREAM_DECODER_LENGTH_STATUS_OK, + /**< The length call was OK and decoding can continue. */ + + FLAC__STREAM_DECODER_LENGTH_STATUS_ERROR, + /**< An unrecoverable error occurred. The decoder will return from the process call. */ + + FLAC__STREAM_DECODER_LENGTH_STATUS_UNSUPPORTED + /**< Client does not support reporting the length. */ + +} FLAC__StreamDecoderLengthStatus; + +/** Maps a FLAC__StreamDecoderLengthStatus to a C string. + * + * Using a FLAC__StreamDecoderLengthStatus as the index to this array + * will give the string equivalent. The contents should not be modified. + */ +extern FLAC_API const char * const FLAC__StreamDecoderLengthStatusString[]; + + +/** Return values for the FLAC__StreamDecoder write callback. + */ +typedef enum { + + FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE, + /**< The write was OK and decoding can continue. */ + + FLAC__STREAM_DECODER_WRITE_STATUS_ABORT + /**< An unrecoverable error occurred. The decoder will return from the process call. */ + +} FLAC__StreamDecoderWriteStatus; + +/** Maps a FLAC__StreamDecoderWriteStatus to a C string. + * + * Using a FLAC__StreamDecoderWriteStatus as the index to this array + * will give the string equivalent. The contents should not be modified. + */ +extern FLAC_API const char * const FLAC__StreamDecoderWriteStatusString[]; + + +/** Possible values passed back to the FLAC__StreamDecoder error callback. + * \c FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC is the generic catch- + * all. The rest could be caused by bad sync (false synchronization on + * data that is not the start of a frame) or corrupted data. The error + * itself is the decoder's best guess at what happened assuming a correct + * sync. For example \c FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER + * could be caused by a correct sync on the start of a frame, but some + * data in the frame header was corrupted. Or it could be the result of + * syncing on a point the stream that looked like the starting of a frame + * but was not. \c FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM + * could be because the decoder encountered a valid frame made by a future + * version of the encoder which it cannot parse, or because of a false + * sync making it appear as though an encountered frame was generated by + * a future encoder. + */ +typedef enum { + + FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC, + /**< An error in the stream caused the decoder to lose synchronization. */ + + FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER, + /**< The decoder encountered a corrupted frame header. */ + + FLAC__STREAM_DECODER_ERROR_STATUS_FRAME_CRC_MISMATCH, + /**< The frame's data did not match the CRC in the footer. */ + + FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM + /**< The decoder encountered reserved fields in use in the stream. */ + +} FLAC__StreamDecoderErrorStatus; + +/** Maps a FLAC__StreamDecoderErrorStatus to a C string. + * + * Using a FLAC__StreamDecoderErrorStatus as the index to this array + * will give the string equivalent. The contents should not be modified. + */ +extern FLAC_API const char * const FLAC__StreamDecoderErrorStatusString[]; + + +/*********************************************************************** + * + * class FLAC__StreamDecoder + * + ***********************************************************************/ + +struct FLAC__StreamDecoderProtected; +struct FLAC__StreamDecoderPrivate; +/** The opaque structure definition for the stream decoder type. + * See the \link flac_stream_decoder stream decoder module \endlink + * for a detailed description. + */ +typedef struct { + struct FLAC__StreamDecoderProtected *protected_; /* avoid the C++ keyword 'protected' */ + struct FLAC__StreamDecoderPrivate *private_; /* avoid the C++ keyword 'private' */ +} FLAC__StreamDecoder; + +/** Signature for the read callback. + * + * A function pointer matching this signature must be passed to + * FLAC__stream_decoder_init*_stream(). The supplied function will be + * called when the decoder needs more input data. The address of the + * buffer to be filled is supplied, along with the number of bytes the + * buffer can hold. The callback may choose to supply less data and + * modify the byte count but must be careful not to overflow the buffer. + * The callback then returns a status code chosen from + * FLAC__StreamDecoderReadStatus. + * + * Here is an example of a read callback for stdio streams: + * \code + * FLAC__StreamDecoderReadStatus read_cb(const FLAC__StreamDecoder *decoder, FLAC__byte buffer[], size_t *bytes, void *client_data) + * { + * FILE *file = ((MyClientData*)client_data)->file; + * if(*bytes > 0) { + * *bytes = fread(buffer, sizeof(FLAC__byte), *bytes, file); + * if(ferror(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; + * } + * \endcode + * + * \note In general, FLAC__StreamDecoder functions which change the + * state should not be called on the \a decoder while in the callback. + * + * \param decoder The decoder instance calling the callback. + * \param buffer A pointer to a location for the callee to store + * data to be decoded. + * \param bytes A pointer to the size of the buffer. On entry + * to the callback, it contains the maximum number + * of bytes that may be stored in \a buffer. The + * callee must set it to the actual number of bytes + * stored (0 in case of error or end-of-stream) before + * returning. + * \param client_data The callee's client data set through + * FLAC__stream_decoder_init_*(). + * \retval FLAC__StreamDecoderReadStatus + * The callee's return status. Note that the callback should return + * \c FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM if and only if + * zero bytes were read and there is no more data to be read. + */ +typedef FLAC__StreamDecoderReadStatus (*FLAC__StreamDecoderReadCallback)(const FLAC__StreamDecoder *decoder, FLAC__byte buffer[], size_t *bytes, void *client_data); + +/** Signature for the seek callback. + * + * A function pointer matching this signature may be passed to + * FLAC__stream_decoder_init*_stream(). The supplied function will be + * called when the decoder needs to seek the input stream. The decoder + * will pass the absolute byte offset to seek to, 0 meaning the + * beginning of the stream. + * + * Here is an example of a seek callback for stdio streams: + * \code + * FLAC__StreamDecoderSeekStatus seek_cb(const FLAC__StreamDecoder *decoder, FLAC__uint64 absolute_byte_offset, void *client_data) + * { + * FILE *file = ((MyClientData*)client_data)->file; + * if(file == stdin) + * return FLAC__STREAM_DECODER_SEEK_STATUS_UNSUPPORTED; + * else if(fseeko(file, (off_t)absolute_byte_offset, SEEK_SET) < 0) + * return FLAC__STREAM_DECODER_SEEK_STATUS_ERROR; + * else + * return FLAC__STREAM_DECODER_SEEK_STATUS_OK; + * } + * \endcode + * + * \note In general, FLAC__StreamDecoder functions which change the + * state should not be called on the \a decoder while in the callback. + * + * \param decoder The decoder instance calling the callback. + * \param absolute_byte_offset The offset from the beginning of the stream + * to seek to. + * \param client_data The callee's client data set through + * FLAC__stream_decoder_init_*(). + * \retval FLAC__StreamDecoderSeekStatus + * The callee's return status. + */ +typedef FLAC__StreamDecoderSeekStatus (*FLAC__StreamDecoderSeekCallback)(const FLAC__StreamDecoder *decoder, FLAC__uint64 absolute_byte_offset, void *client_data); + +/** Signature for the tell callback. + * + * A function pointer matching this signature may be passed to + * FLAC__stream_decoder_init*_stream(). The supplied function will be + * called when the decoder wants to know the current position of the + * stream. The callback should return the byte offset from the + * beginning of the stream. + * + * Here is an example of a tell callback for stdio streams: + * \code + * FLAC__StreamDecoderTellStatus tell_cb(const FLAC__StreamDecoder *decoder, FLAC__uint64 *absolute_byte_offset, void *client_data) + * { + * FILE *file = ((MyClientData*)client_data)->file; + * off_t pos; + * if(file == stdin) + * return FLAC__STREAM_DECODER_TELL_STATUS_UNSUPPORTED; + * else if((pos = ftello(file)) < 0) + * return FLAC__STREAM_DECODER_TELL_STATUS_ERROR; + * else { + * *absolute_byte_offset = (FLAC__uint64)pos; + * return FLAC__STREAM_DECODER_TELL_STATUS_OK; + * } + * } + * \endcode + * + * \note In general, FLAC__StreamDecoder functions which change the + * state should not be called on the \a decoder while in the callback. + * + * \param decoder The decoder instance calling the callback. + * \param absolute_byte_offset A pointer to storage for the current offset + * from the beginning of the stream. + * \param client_data The callee's client data set through + * FLAC__stream_decoder_init_*(). + * \retval FLAC__StreamDecoderTellStatus + * The callee's return status. + */ +typedef FLAC__StreamDecoderTellStatus (*FLAC__StreamDecoderTellCallback)(const FLAC__StreamDecoder *decoder, FLAC__uint64 *absolute_byte_offset, void *client_data); + +/** Signature for the length callback. + * + * A function pointer matching this signature may be passed to + * FLAC__stream_decoder_init*_stream(). The supplied function will be + * called when the decoder wants to know the total length of the stream + * in bytes. + * + * Here is an example of a length callback for stdio streams: + * \code + * FLAC__StreamDecoderLengthStatus length_cb(const FLAC__StreamDecoder *decoder, FLAC__uint64 *stream_length, void *client_data) + * { + * FILE *file = ((MyClientData*)client_data)->file; + * struct stat filestats; + * + * if(file == stdin) + * return FLAC__STREAM_DECODER_LENGTH_STATUS_UNSUPPORTED; + * else if(fstat(fileno(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; + * } + * } + * \endcode + * + * \note In general, FLAC__StreamDecoder functions which change the + * state should not be called on the \a decoder while in the callback. + * + * \param decoder The decoder instance calling the callback. + * \param stream_length A pointer to storage for the length of the stream + * in bytes. + * \param client_data The callee's client data set through + * FLAC__stream_decoder_init_*(). + * \retval FLAC__StreamDecoderLengthStatus + * The callee's return status. + */ +typedef FLAC__StreamDecoderLengthStatus (*FLAC__StreamDecoderLengthCallback)(const FLAC__StreamDecoder *decoder, FLAC__uint64 *stream_length, void *client_data); + +/** Signature for the EOF callback. + * + * A function pointer matching this signature may be passed to + * FLAC__stream_decoder_init*_stream(). The supplied function will be + * called when the decoder needs to know if the end of the stream has + * been reached. + * + * Here is an example of a EOF callback for stdio streams: + * FLAC__bool eof_cb(const FLAC__StreamDecoder *decoder, void *client_data) + * \code + * { + * FILE *file = ((MyClientData*)client_data)->file; + * return feof(file)? true : false; + * } + * \endcode + * + * \note In general, FLAC__StreamDecoder functions which change the + * state should not be called on the \a decoder while in the callback. + * + * \param decoder The decoder instance calling the callback. + * \param client_data The callee's client data set through + * FLAC__stream_decoder_init_*(). + * \retval FLAC__bool + * \c true if the currently at the end of the stream, else \c false. + */ +typedef FLAC__bool (*FLAC__StreamDecoderEofCallback)(const FLAC__StreamDecoder *decoder, void *client_data); + +/** Signature for the write callback. + * + * A function pointer matching this signature must be passed to one of + * the FLAC__stream_decoder_init_*() functions. + * The supplied function will be called when the decoder has decoded a + * single audio frame. The decoder will pass the frame metadata as well + * as an array of pointers (one for each channel) pointing to the + * decoded audio. + * + * \note In general, FLAC__StreamDecoder functions which change the + * state should not be called on the \a decoder while in the callback. + * + * \param decoder The decoder instance calling the callback. + * \param frame The description of the decoded frame. See + * FLAC__Frame. + * \param buffer An array of pointers to decoded channels of data. + * Each pointer will point to an array of signed + * samples of length \a frame->header.blocksize. + * Channels will be ordered according to the FLAC + * specification; see the documentation for the + * <A HREF="../format.html#frame_header">frame header</A>. + * \param client_data The callee's client data set through + * FLAC__stream_decoder_init_*(). + * \retval FLAC__StreamDecoderWriteStatus + * The callee's return status. + */ +typedef FLAC__StreamDecoderWriteStatus (*FLAC__StreamDecoderWriteCallback)(const FLAC__StreamDecoder *decoder, const FLAC__Frame *frame, const FLAC__int32 * const buffer[], void *client_data); + +/** Signature for the metadata callback. + * + * A function pointer matching this signature must be passed to one of + * the FLAC__stream_decoder_init_*() functions. + * The supplied function will be called when the decoder has decoded a + * metadata block. In a valid FLAC file there will always be one + * \c STREAMINFO block, followed by zero or more other metadata blocks. + * These will be supplied by the decoder in the same order as they + * appear in the stream and always before the first audio frame (i.e. + * write callback). The metadata block that is passed in must not be + * modified, and it doesn't live beyond the callback, so you should make + * a copy of it with FLAC__metadata_object_clone() if you will need it + * elsewhere. Since metadata blocks can potentially be large, by + * default the decoder only calls the metadata callback for the + * \c STREAMINFO block; you can instruct the decoder to pass or filter + * other blocks with FLAC__stream_decoder_set_metadata_*() calls. + * + * \note In general, FLAC__StreamDecoder functions which change the + * state should not be called on the \a decoder while in the callback. + * + * \param decoder The decoder instance calling the callback. + * \param metadata The decoded metadata block. + * \param client_data The callee's client data set through + * FLAC__stream_decoder_init_*(). + */ +typedef void (*FLAC__StreamDecoderMetadataCallback)(const FLAC__StreamDecoder *decoder, const FLAC__StreamMetadata *metadata, void *client_data); + +/** Signature for the error callback. + * + * A function pointer matching this signature must be passed to one of + * the FLAC__stream_decoder_init_*() functions. + * The supplied function will be called whenever an error occurs during + * decoding. + * + * \note In general, FLAC__StreamDecoder functions which change the + * state should not be called on the \a decoder while in the callback. + * + * \param decoder The decoder instance calling the callback. + * \param status The error encountered by the decoder. + * \param client_data The callee's client data set through + * FLAC__stream_decoder_init_*(). + */ +typedef void (*FLAC__StreamDecoderErrorCallback)(const FLAC__StreamDecoder *decoder, FLAC__StreamDecoderErrorStatus status, void *client_data); + + +/*********************************************************************** + * + * Class constructor/destructor + * + ***********************************************************************/ + +/** Create a new stream decoder instance. The instance is created with + * default settings; see the individual FLAC__stream_decoder_set_*() + * functions for each setting's default. + * + * \retval FLAC__StreamDecoder* + * \c NULL if there was an error allocating memory, else the new instance. + */ +FLAC_API FLAC__StreamDecoder *FLAC__stream_decoder_new(void); + +/** Free a decoder instance. Deletes the object pointed to by \a decoder. + * + * \param decoder A pointer to an existing decoder. + * \assert + * \code decoder != NULL \endcode + */ +FLAC_API void FLAC__stream_decoder_delete(FLAC__StreamDecoder *decoder); + + +/*********************************************************************** + * + * Public class method prototypes + * + ***********************************************************************/ + +/** Set the serial number for the FLAC stream within the Ogg container. + * The default behavior is to use the serial number of the first Ogg + * page. Setting a serial number here will explicitly specify which + * stream is to be decoded. + * + * \note + * This does not need to be set for native FLAC decoding. + * + * \default \c use serial number of first page + * \param decoder A decoder instance to set. + * \param serial_number See above. + * \assert + * \code decoder != NULL \endcode + * \retval FLAC__bool + * \c false if the decoder is already initialized, else \c true. + */ +FLAC_API FLAC__bool FLAC__stream_decoder_set_ogg_serial_number(FLAC__StreamDecoder *decoder, long serial_number); + +/** Set the "MD5 signature checking" flag. If \c true, the decoder will + * compute the MD5 signature of the unencoded audio data while decoding + * and compare it to the signature from the STREAMINFO block, if it + * exists, during FLAC__stream_decoder_finish(). + * + * MD5 signature checking will be turned off (until the next + * FLAC__stream_decoder_reset()) if there is no signature in the + * STREAMINFO block or when a seek is attempted. + * + * Clients that do not use the MD5 check should leave this off to speed + * up decoding. + * + * \default \c false + * \param decoder A decoder instance to set. + * \param value Flag value (see above). + * \assert + * \code decoder != NULL \endcode + * \retval FLAC__bool + * \c false if the decoder is already initialized, else \c true. + */ +FLAC_API FLAC__bool FLAC__stream_decoder_set_md5_checking(FLAC__StreamDecoder *decoder, FLAC__bool value); + +/** Direct the decoder to pass on all metadata blocks of type \a type. + * + * \default By default, only the \c STREAMINFO block is returned via the + * metadata callback. + * \param decoder A decoder instance to set. + * \param type See above. + * \assert + * \code decoder != NULL \endcode + * \a type is valid + * \retval FLAC__bool + * \c false if the decoder is already initialized, else \c true. + */ +FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_respond(FLAC__StreamDecoder *decoder, FLAC__MetadataType type); + +/** Direct the decoder to pass on all APPLICATION metadata blocks of the + * given \a id. + * + * \default By default, only the \c STREAMINFO block is returned via the + * metadata callback. + * \param decoder A decoder instance to set. + * \param id See above. + * \assert + * \code decoder != NULL \endcode + * \code id != NULL \endcode + * \retval FLAC__bool + * \c false if the decoder is already initialized, else \c true. + */ +FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_respond_application(FLAC__StreamDecoder *decoder, const FLAC__byte id[4]); + +/** Direct the decoder to pass on all metadata blocks of any type. + * + * \default By default, only the \c STREAMINFO block is returned via the + * metadata callback. + * \param decoder A decoder instance to set. + * \assert + * \code decoder != NULL \endcode + * \retval FLAC__bool + * \c false if the decoder is already initialized, else \c true. + */ +FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_respond_all(FLAC__StreamDecoder *decoder); + +/** Direct the decoder to filter out all metadata blocks of type \a type. + * + * \default By default, only the \c STREAMINFO block is returned via the + * metadata callback. + * \param decoder A decoder instance to set. + * \param type See above. + * \assert + * \code decoder != NULL \endcode + * \a type is valid + * \retval FLAC__bool + * \c false if the decoder is already initialized, else \c true. + */ +FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_ignore(FLAC__StreamDecoder *decoder, FLAC__MetadataType type); + +/** Direct the decoder to filter out all APPLICATION metadata blocks of + * the given \a id. + * + * \default By default, only the \c STREAMINFO block is returned via the + * metadata callback. + * \param decoder A decoder instance to set. + * \param id See above. + * \assert + * \code decoder != NULL \endcode + * \code id != NULL \endcode + * \retval FLAC__bool + * \c false if the decoder is already initialized, else \c true. + */ +FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_ignore_application(FLAC__StreamDecoder *decoder, const FLAC__byte id[4]); + +/** Direct the decoder to filter out all metadata blocks of any type. + * + * \default By default, only the \c STREAMINFO block is returned via the + * metadata callback. + * \param decoder A decoder instance to set. + * \assert + * \code decoder != NULL \endcode + * \retval FLAC__bool + * \c false if the decoder is already initialized, else \c true. + */ +FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_ignore_all(FLAC__StreamDecoder *decoder); + +/** Get the current decoder state. + * + * \param decoder A decoder instance to query. + * \assert + * \code decoder != NULL \endcode + * \retval FLAC__StreamDecoderState + * The current decoder state. + */ +FLAC_API FLAC__StreamDecoderState FLAC__stream_decoder_get_state(const FLAC__StreamDecoder *decoder); + +/** Get the current decoder state as a C string. + * + * \param decoder A decoder instance to query. + * \assert + * \code decoder != NULL \endcode + * \retval const char * + * The decoder state as a C string. Do not modify the contents. + */ +FLAC_API const char *FLAC__stream_decoder_get_resolved_state_string(const FLAC__StreamDecoder *decoder); + +/** Get the "MD5 signature checking" flag. + * This is the value of the setting, not whether or not the decoder is + * currently checking the MD5 (remember, it can be turned off automatically + * by a seek). When the decoder is reset the flag will be restored to the + * value returned by this function. + * + * \param decoder A decoder instance to query. + * \assert + * \code decoder != NULL \endcode + * \retval FLAC__bool + * See above. + */ +FLAC_API FLAC__bool FLAC__stream_decoder_get_md5_checking(const FLAC__StreamDecoder *decoder); + +/** Get the total number of samples in the stream being decoded. + * Will only be valid after decoding has started and will contain the + * value from the \c STREAMINFO block. A value of \c 0 means "unknown". + * + * \param decoder A decoder instance to query. + * \assert + * \code decoder != NULL \endcode + * \retval unsigned + * See above. + */ +FLAC_API FLAC__uint64 FLAC__stream_decoder_get_total_samples(const FLAC__StreamDecoder *decoder); + +/** Get the current number of channels in the stream being decoded. + * Will only be valid after decoding has started and will contain the + * value from the most recently decoded frame header. + * + * \param decoder A decoder instance to query. + * \assert + * \code decoder != NULL \endcode + * \retval unsigned + * See above. + */ +FLAC_API unsigned FLAC__stream_decoder_get_channels(const FLAC__StreamDecoder *decoder); + +/** Get the current channel assignment in the stream being decoded. + * Will only be valid after decoding has started and will contain the + * value from the most recently decoded frame header. + * + * \param decoder A decoder instance to query. + * \assert + * \code decoder != NULL \endcode + * \retval FLAC__ChannelAssignment + * See above. + */ +FLAC_API FLAC__ChannelAssignment FLAC__stream_decoder_get_channel_assignment(const FLAC__StreamDecoder *decoder); + +/** Get the current sample resolution in the stream being decoded. + * Will only be valid after decoding has started and will contain the + * value from the most recently decoded frame header. + * + * \param decoder A decoder instance to query. + * \assert + * \code decoder != NULL \endcode + * \retval unsigned + * See above. + */ +FLAC_API unsigned FLAC__stream_decoder_get_bits_per_sample(const FLAC__StreamDecoder *decoder); + +/** Get the current sample rate in Hz of the stream being decoded. + * Will only be valid after decoding has started and will contain the + * value from the most recently decoded frame header. + * + * \param decoder A decoder instance to query. + * \assert + * \code decoder != NULL \endcode + * \retval unsigned + * See above. + */ +FLAC_API unsigned FLAC__stream_decoder_get_sample_rate(const FLAC__StreamDecoder *decoder); + +/** Get the current blocksize of the stream being decoded. + * Will only be valid after decoding has started and will contain the + * value from the most recently decoded frame header. + * + * \param decoder A decoder instance to query. + * \assert + * \code decoder != NULL \endcode + * \retval unsigned + * See above. + */ +FLAC_API unsigned FLAC__stream_decoder_get_blocksize(const FLAC__StreamDecoder *decoder); + +/** Returns the decoder's current read position within the stream. + * The position is the byte offset from the start of the stream. + * Bytes before this position have been fully decoded. Note that + * there may still be undecoded bytes in the decoder's read FIFO. + * The returned position is correct even after a seek. + * + * \warning This function currently only works for native FLAC, + * not Ogg FLAC streams. + * + * \param decoder A decoder instance to query. + * \param position Address at which to return the desired position. + * \assert + * \code decoder != NULL \endcode + * \code position != NULL \endcode + * \retval FLAC__bool + * \c true if successful, \c false if the stream is not native FLAC, + * or there was an error from the 'tell' callback or it returned + * \c FLAC__STREAM_DECODER_TELL_STATUS_UNSUPPORTED. + */ +FLAC_API FLAC__bool FLAC__stream_decoder_get_decode_position(const FLAC__StreamDecoder *decoder, FLAC__uint64 *position); + +/** Initialize the decoder instance to decode native FLAC streams. + * + * This flavor of initialization sets up the decoder to decode from a + * native FLAC stream. I/O is performed via callbacks to the client. + * For decoding from a plain file via filename or open FILE*, + * FLAC__stream_decoder_init_file() and FLAC__stream_decoder_init_FILE() + * provide a simpler interface. + * + * This function should be called after FLAC__stream_decoder_new() and + * FLAC__stream_decoder_set_*() but before any of the + * FLAC__stream_decoder_process_*() functions. Will set and return the + * decoder state, which will be FLAC__STREAM_DECODER_SEARCH_FOR_METADATA + * if initialization succeeded. + * + * \param decoder An uninitialized decoder instance. + * \param read_callback See FLAC__StreamDecoderReadCallback. This + * pointer must not be \c NULL. + * \param seek_callback See FLAC__StreamDecoderSeekCallback. This + * pointer may be \c NULL if seeking is not + * supported. If \a seek_callback is not \c NULL then a + * \a tell_callback, \a length_callback, and \a eof_callback must also be supplied. + * Alternatively, a dummy seek callback that just + * returns \c FLAC__STREAM_DECODER_SEEK_STATUS_UNSUPPORTED + * may also be supplied, all though this is slightly + * less efficient for the decoder. + * \param tell_callback See FLAC__StreamDecoderTellCallback. This + * pointer may be \c NULL if not supported by the client. If + * \a seek_callback is not \c NULL then a + * \a tell_callback must also be supplied. + * Alternatively, a dummy tell callback that just + * returns \c FLAC__STREAM_DECODER_TELL_STATUS_UNSUPPORTED + * may also be supplied, all though this is slightly + * less efficient for the decoder. + * \param length_callback See FLAC__StreamDecoderLengthCallback. This + * pointer may be \c NULL if not supported by the client. If + * \a seek_callback is not \c NULL then a + * \a length_callback must also be supplied. + * Alternatively, a dummy length callback that just + * returns \c FLAC__STREAM_DECODER_LENGTH_STATUS_UNSUPPORTED + * may also be supplied, all though this is slightly + * less efficient for the decoder. + * \param eof_callback See FLAC__StreamDecoderEofCallback. This + * pointer may be \c NULL if not supported by the client. If + * \a seek_callback is not \c NULL then a + * \a eof_callback must also be supplied. + * Alternatively, a dummy length callback that just + * returns \c false + * may also be supplied, all though this is slightly + * less efficient for the decoder. + * \param write_callback See FLAC__StreamDecoderWriteCallback. This + * pointer must not be \c NULL. + * \param metadata_callback See FLAC__StreamDecoderMetadataCallback. This + * pointer may be \c NULL if the callback is not + * desired. + * \param error_callback See FLAC__StreamDecoderErrorCallback. This + * pointer must not be \c NULL. + * \param client_data This value will be supplied to callbacks in their + * \a client_data argument. + * \assert + * \code decoder != NULL \endcode + * \retval FLAC__StreamDecoderInitStatus + * \c FLAC__STREAM_DECODER_INIT_STATUS_OK if initialization was successful; + * see FLAC__StreamDecoderInitStatus for the meanings of other return values. + */ +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 +); + +/** Initialize the decoder instance to decode Ogg FLAC streams. + * + * This flavor of initialization sets up the decoder to decode from a + * FLAC stream in an Ogg container. I/O is performed via callbacks to the + * client. For decoding from a plain file via filename or open FILE*, + * FLAC__stream_decoder_init_ogg_file() and FLAC__stream_decoder_init_ogg_FILE() + * provide a simpler interface. + * + * This function should be called after FLAC__stream_decoder_new() and + * FLAC__stream_decoder_set_*() but before any of the + * FLAC__stream_decoder_process_*() functions. Will set and return the + * decoder state, which will be FLAC__STREAM_DECODER_SEARCH_FOR_METADATA + * if initialization succeeded. + * + * \note Support for Ogg FLAC in the library is optional. If this + * library has been built without support for Ogg FLAC, this function + * will return \c FLAC__STREAM_DECODER_INIT_STATUS_UNSUPPORTED_CONTAINER. + * + * \param decoder An uninitialized decoder instance. + * \param read_callback See FLAC__StreamDecoderReadCallback. This + * pointer must not be \c NULL. + * \param seek_callback See FLAC__StreamDecoderSeekCallback. This + * pointer may be \c NULL if seeking is not + * supported. If \a seek_callback is not \c NULL then a + * \a tell_callback, \a length_callback, and \a eof_callback must also be supplied. + * Alternatively, a dummy seek callback that just + * returns \c FLAC__STREAM_DECODER_SEEK_STATUS_UNSUPPORTED + * may also be supplied, all though this is slightly + * less efficient for the decoder. + * \param tell_callback See FLAC__StreamDecoderTellCallback. This + * pointer may be \c NULL if not supported by the client. If + * \a seek_callback is not \c NULL then a + * \a tell_callback must also be supplied. + * Alternatively, a dummy tell callback that just + * returns \c FLAC__STREAM_DECODER_TELL_STATUS_UNSUPPORTED + * may also be supplied, all though this is slightly + * less efficient for the decoder. + * \param length_callback See FLAC__StreamDecoderLengthCallback. This + * pointer may be \c NULL if not supported by the client. If + * \a seek_callback is not \c NULL then a + * \a length_callback must also be supplied. + * Alternatively, a dummy length callback that just + * returns \c FLAC__STREAM_DECODER_LENGTH_STATUS_UNSUPPORTED + * may also be supplied, all though this is slightly + * less efficient for the decoder. + * \param eof_callback See FLAC__StreamDecoderEofCallback. This + * pointer may be \c NULL if not supported by the client. If + * \a seek_callback is not \c NULL then a + * \a eof_callback must also be supplied. + * Alternatively, a dummy length callback that just + * returns \c false + * may also be supplied, all though this is slightly + * less efficient for the decoder. + * \param write_callback See FLAC__StreamDecoderWriteCallback. This + * pointer must not be \c NULL. + * \param metadata_callback See FLAC__StreamDecoderMetadataCallback. This + * pointer may be \c NULL if the callback is not + * desired. + * \param error_callback See FLAC__StreamDecoderErrorCallback. This + * pointer must not be \c NULL. + * \param client_data This value will be supplied to callbacks in their + * \a client_data argument. + * \assert + * \code decoder != NULL \endcode + * \retval FLAC__StreamDecoderInitStatus + * \c FLAC__STREAM_DECODER_INIT_STATUS_OK if initialization was successful; + * see FLAC__StreamDecoderInitStatus for the meanings of other return values. + */ +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 +); + +/** Initialize the decoder instance to decode native FLAC files. + * + * This flavor of initialization sets up the decoder to decode from a + * plain native FLAC file. For non-stdio streams, you must use + * FLAC__stream_decoder_init_stream() and provide callbacks for the I/O. + * + * This function should be called after FLAC__stream_decoder_new() and + * FLAC__stream_decoder_set_*() but before any of the + * FLAC__stream_decoder_process_*() functions. Will set and return the + * decoder state, which will be FLAC__STREAM_DECODER_SEARCH_FOR_METADATA + * if initialization succeeded. + * + * \param decoder An uninitialized decoder instance. + * \param file An open FLAC file. The file should have been + * opened with mode \c "rb" and rewound. The file + * becomes owned by the decoder and should not be + * manipulated by the client while decoding. + * Unless \a file is \c stdin, it will be closed + * when FLAC__stream_decoder_finish() is called. + * Note however that seeking will not work when + * decoding from \c stdout since it is not seekable. + * \param write_callback See FLAC__StreamDecoderWriteCallback. This + * pointer must not be \c NULL. + * \param metadata_callback See FLAC__StreamDecoderMetadataCallback. This + * pointer may be \c NULL if the callback is not + * desired. + * \param error_callback See FLAC__StreamDecoderErrorCallback. This + * pointer must not be \c NULL. + * \param client_data This value will be supplied to callbacks in their + * \a client_data argument. + * \assert + * \code decoder != NULL \endcode + * \code file != NULL \endcode + * \retval FLAC__StreamDecoderInitStatus + * \c FLAC__STREAM_DECODER_INIT_STATUS_OK if initialization was successful; + * see FLAC__StreamDecoderInitStatus for the meanings of other return values. + */ +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 +); + +/** Initialize the decoder instance to decode Ogg FLAC files. + * + * This flavor of initialization sets up the decoder to decode from a + * plain Ogg FLAC file. For non-stdio streams, you must use + * FLAC__stream_decoder_init_ogg_stream() and provide callbacks for the I/O. + * + * This function should be called after FLAC__stream_decoder_new() and + * FLAC__stream_decoder_set_*() but before any of the + * FLAC__stream_decoder_process_*() functions. Will set and return the + * decoder state, which will be FLAC__STREAM_DECODER_SEARCH_FOR_METADATA + * if initialization succeeded. + * + * \note Support for Ogg FLAC in the library is optional. If this + * library has been built without support for Ogg FLAC, this function + * will return \c FLAC__STREAM_DECODER_INIT_STATUS_UNSUPPORTED_CONTAINER. + * + * \param decoder An uninitialized decoder instance. + * \param file An open FLAC file. The file should have been + * opened with mode \c "rb" and rewound. The file + * becomes owned by the decoder and should not be + * manipulated by the client while decoding. + * Unless \a file is \c stdin, it will be closed + * when FLAC__stream_decoder_finish() is called. + * Note however that seeking will not work when + * decoding from \c stdout since it is not seekable. + * \param write_callback See FLAC__StreamDecoderWriteCallback. This + * pointer must not be \c NULL. + * \param metadata_callback See FLAC__StreamDecoderMetadataCallback. This + * pointer may be \c NULL if the callback is not + * desired. + * \param error_callback See FLAC__StreamDecoderErrorCallback. This + * pointer must not be \c NULL. + * \param client_data This value will be supplied to callbacks in their + * \a client_data argument. + * \assert + * \code decoder != NULL \endcode + * \code file != NULL \endcode + * \retval FLAC__StreamDecoderInitStatus + * \c FLAC__STREAM_DECODER_INIT_STATUS_OK if initialization was successful; + * see FLAC__StreamDecoderInitStatus for the meanings of other return values. + */ +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 +); + +/** Initialize the decoder instance to decode native FLAC files. + * + * This flavor of initialization sets up the decoder to decode from a plain + * native FLAC file. If POSIX fopen() semantics are not sufficient, (for + * example, with Unicode filenames on Windows), you must use + * FLAC__stream_decoder_init_FILE(), or FLAC__stream_decoder_init_stream() + * and provide callbacks for the I/O. + * + * This function should be called after FLAC__stream_decoder_new() and + * FLAC__stream_decoder_set_*() but before any of the + * FLAC__stream_decoder_process_*() functions. Will set and return the + * decoder state, which will be FLAC__STREAM_DECODER_SEARCH_FOR_METADATA + * if initialization succeeded. + * + * \param decoder An uninitialized decoder instance. + * \param filename The name of the file to decode from. The file will + * be opened with fopen(). Use \c NULL to decode from + * \c stdin. Note that \c stdin is not seekable. + * \param write_callback See FLAC__StreamDecoderWriteCallback. This + * pointer must not be \c NULL. + * \param metadata_callback See FLAC__StreamDecoderMetadataCallback. This + * pointer may be \c NULL if the callback is not + * desired. + * \param error_callback See FLAC__StreamDecoderErrorCallback. This + * pointer must not be \c NULL. + * \param client_data This value will be supplied to callbacks in their + * \a client_data argument. + * \assert + * \code decoder != NULL \endcode + * \retval FLAC__StreamDecoderInitStatus + * \c FLAC__STREAM_DECODER_INIT_STATUS_OK if initialization was successful; + * see FLAC__StreamDecoderInitStatus for the meanings of other return values. + */ +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 +); + +/** Initialize the decoder instance to decode Ogg FLAC files. + * + * This flavor of initialization sets up the decoder to decode from a plain + * Ogg FLAC file. If POSIX fopen() semantics are not sufficient, (for + * example, with Unicode filenames on Windows), you must use + * FLAC__stream_decoder_init_ogg_FILE(), or FLAC__stream_decoder_init_ogg_stream() + * and provide callbacks for the I/O. + * + * This function should be called after FLAC__stream_decoder_new() and + * FLAC__stream_decoder_set_*() but before any of the + * FLAC__stream_decoder_process_*() functions. Will set and return the + * decoder state, which will be FLAC__STREAM_DECODER_SEARCH_FOR_METADATA + * if initialization succeeded. + * + * \note Support for Ogg FLAC in the library is optional. If this + * library has been built without support for Ogg FLAC, this function + * will return \c FLAC__STREAM_DECODER_INIT_STATUS_UNSUPPORTED_CONTAINER. + * + * \param decoder An uninitialized decoder instance. + * \param filename The name of the file to decode from. The file will + * be opened with fopen(). Use \c NULL to decode from + * \c stdin. Note that \c stdin is not seekable. + * \param write_callback See FLAC__StreamDecoderWriteCallback. This + * pointer must not be \c NULL. + * \param metadata_callback See FLAC__StreamDecoderMetadataCallback. This + * pointer may be \c NULL if the callback is not + * desired. + * \param error_callback See FLAC__StreamDecoderErrorCallback. This + * pointer must not be \c NULL. + * \param client_data This value will be supplied to callbacks in their + * \a client_data argument. + * \assert + * \code decoder != NULL \endcode + * \retval FLAC__StreamDecoderInitStatus + * \c FLAC__STREAM_DECODER_INIT_STATUS_OK if initialization was successful; + * see FLAC__StreamDecoderInitStatus for the meanings of other return values. + */ +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 +); + +/** Finish the decoding process. + * Flushes the decoding buffer, releases resources, resets the decoder + * settings to their defaults, and returns the decoder state to + * FLAC__STREAM_DECODER_UNINITIALIZED. + * + * In the event of a prematurely-terminated decode, it is not strictly + * necessary to call this immediately before FLAC__stream_decoder_delete() + * but it is good practice to match every FLAC__stream_decoder_init_*() + * with a FLAC__stream_decoder_finish(). + * + * \param decoder An uninitialized decoder instance. + * \assert + * \code decoder != NULL \endcode + * \retval FLAC__bool + * \c false if MD5 checking is on AND a STREAMINFO block was available + * AND the MD5 signature in the STREAMINFO block was non-zero AND the + * signature does not match the one computed by the decoder; else + * \c true. + */ +FLAC_API FLAC__bool FLAC__stream_decoder_finish(FLAC__StreamDecoder *decoder); + +/** Flush the stream input. + * The decoder's input buffer will be cleared and the state set to + * \c FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC. This will also turn + * off MD5 checking. + * + * \param decoder A decoder instance. + * \assert + * \code decoder != NULL \endcode + * \retval FLAC__bool + * \c true if successful, else \c false if a memory allocation + * error occurs (in which case the state will be set to + * \c FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR). + */ +FLAC_API FLAC__bool FLAC__stream_decoder_flush(FLAC__StreamDecoder *decoder); + +/** Reset the decoding process. + * The decoder's input buffer will be cleared and the state set to + * \c FLAC__STREAM_DECODER_SEARCH_FOR_METADATA. This is similar to + * FLAC__stream_decoder_finish() except that the settings are + * preserved; there is no need to call FLAC__stream_decoder_init_*() + * before decoding again. MD5 checking will be restored to its original + * setting. + * + * If the decoder is seekable, or was initialized with + * FLAC__stream_decoder_init*_FILE() or FLAC__stream_decoder_init*_file(), + * the decoder will also attempt to seek to the beginning of the file. + * If this rewind fails, this function will return \c false. It follows + * that FLAC__stream_decoder_reset() cannot be used when decoding from + * \c stdin. + * + * If the decoder was initialized with FLAC__stream_encoder_init*_stream() + * and is not seekable (i.e. no seek callback was provided or the seek + * callback returns \c FLAC__STREAM_DECODER_SEEK_STATUS_UNSUPPORTED), it + * is the duty of the client to start feeding data from the beginning of + * the stream on the next FLAC__stream_decoder_process() or + * FLAC__stream_decoder_process_interleaved() call. + * + * \param decoder A decoder instance. + * \assert + * \code decoder != NULL \endcode + * \retval FLAC__bool + * \c true if successful, else \c false if a memory allocation occurs + * (in which case the state will be set to + * \c FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR) or a seek error + * occurs (the state will be unchanged). + */ +FLAC_API FLAC__bool FLAC__stream_decoder_reset(FLAC__StreamDecoder *decoder); + +/** Decode one metadata block or audio frame. + * This version instructs the decoder to decode a either a single metadata + * block or a single frame and stop, unless the callbacks return a fatal + * error or the read callback returns + * \c FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM. + * + * As the decoder needs more input it will call the read callback. + * Depending on what was decoded, the metadata or write callback will be + * called with the decoded metadata block or audio frame. + * + * Unless there is a fatal read error or end of stream, this function + * will return once one whole frame is decoded. In other words, if the + * stream is not synchronized or points to a corrupt frame header, the + * decoder will continue to try and resync until it gets to a valid + * frame, then decode one frame, then return. If the decoder points to + * a frame whose frame CRC in the frame footer does not match the + * computed frame CRC, this function will issue a + * FLAC__STREAM_DECODER_ERROR_STATUS_FRAME_CRC_MISMATCH error to the + * error callback, and return, having decoded one complete, although + * corrupt, frame. (Such corrupted frames are sent as silence of the + * correct length to the write callback.) + * + * \param decoder An initialized decoder instance. + * \assert + * \code decoder != NULL \endcode + * \retval FLAC__bool + * \c false if any fatal read, write, or memory allocation error + * occurred (meaning decoding must stop), else \c true; for more + * information about the decoder, check the decoder state with + * FLAC__stream_decoder_get_state(). + */ +FLAC_API FLAC__bool FLAC__stream_decoder_process_single(FLAC__StreamDecoder *decoder); + +/** Decode until the end of the metadata. + * This version instructs the decoder to decode from the current position + * and continue until all the metadata has been read, or until the + * callbacks return a fatal error or the read callback returns + * \c FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM. + * + * As the decoder needs more input it will call the read callback. + * As each metadata block is decoded, the metadata callback will be called + * with the decoded metadata. + * + * \param decoder An initialized decoder instance. + * \assert + * \code decoder != NULL \endcode + * \retval FLAC__bool + * \c false if any fatal read, write, or memory allocation error + * occurred (meaning decoding must stop), else \c true; for more + * information about the decoder, check the decoder state with + * FLAC__stream_decoder_get_state(). + */ +FLAC_API FLAC__bool FLAC__stream_decoder_process_until_end_of_metadata(FLAC__StreamDecoder *decoder); + +/** Decode until the end of the stream. + * This version instructs the decoder to decode from the current position + * and continue until the end of stream (the read callback returns + * \c FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM), or until the + * callbacks return a fatal error. + * + * As the decoder needs more input it will call the read callback. + * As each metadata block and frame is decoded, the metadata or write + * callback will be called with the decoded metadata or frame. + * + * \param decoder An initialized decoder instance. + * \assert + * \code decoder != NULL \endcode + * \retval FLAC__bool + * \c false if any fatal read, write, or memory allocation error + * occurred (meaning decoding must stop), else \c true; for more + * information about the decoder, check the decoder state with + * FLAC__stream_decoder_get_state(). + */ +FLAC_API FLAC__bool FLAC__stream_decoder_process_until_end_of_stream(FLAC__StreamDecoder *decoder); + +/** Skip one audio frame. + * This version instructs the decoder to 'skip' a single frame and stop, + * unless the callbacks return a fatal error or the read callback returns + * \c FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM. + * + * The decoding flow is the same as what occurs when + * FLAC__stream_decoder_process_single() is called to process an audio + * frame, except that this function does not decode the parsed data into + * PCM or call the write callback. The integrity of the frame is still + * checked the same way as in the other process functions. + * + * This function will return once one whole frame is skipped, in the + * same way that FLAC__stream_decoder_process_single() will return once + * one whole frame is decoded. + * + * This function can be used in more quickly determining FLAC frame + * boundaries when decoding of the actual data is not needed, for + * example when an application is separating a FLAC stream into frames + * for editing or storing in a container. To do this, the application + * can use FLAC__stream_decoder_skip_single_frame() to quickly advance + * to the next frame, then use + * FLAC__stream_decoder_get_decode_position() to find the new frame + * boundary. + * + * This function should only be called when the stream has advanced + * past all the metadata, otherwise it will return \c false. + * + * \param decoder An initialized decoder instance not in a metadata + * state. + * \assert + * \code decoder != NULL \endcode + * \retval FLAC__bool + * \c false if any fatal read, write, or memory allocation error + * occurred (meaning decoding must stop), or if the decoder + * is in the FLAC__STREAM_DECODER_SEARCH_FOR_METADATA or + * FLAC__STREAM_DECODER_READ_METADATA state, else \c true; for more + * information about the decoder, check the decoder state with + * FLAC__stream_decoder_get_state(). + */ +FLAC_API FLAC__bool FLAC__stream_decoder_skip_single_frame(FLAC__StreamDecoder *decoder); + +/** Flush the input and seek to an absolute sample. + * Decoding will resume at the given sample. Note that because of + * this, the next write callback may contain a partial block. The + * client must support seeking the input or this function will fail + * and return \c false. Furthermore, if the decoder state is + * \c FLAC__STREAM_DECODER_SEEK_ERROR, then the decoder must be flushed + * with FLAC__stream_decoder_flush() or reset with + * FLAC__stream_decoder_reset() before decoding can continue. + * + * \param decoder A decoder instance. + * \param sample The target sample number to seek to. + * \assert + * \code decoder != NULL \endcode + * \retval FLAC__bool + * \c true if successful, else \c false. + */ +FLAC_API FLAC__bool FLAC__stream_decoder_seek_absolute(FLAC__StreamDecoder *decoder, FLAC__uint64 sample); + +/* \} */ + +#ifdef __cplusplus +} +#endif + +#endif