file_decoder.h

在x86平台上运行不可信任代码的sandbox。

/* libFLAC - Free Lossless Audio Codec library
 * Copyright (C) 2000,2001,2002,2003,2004,2005  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__FILE_DECODER_H
#define FLAC__FILE_DECODER_H

#include "export.h"
#include "seekable_stream_decoder.h"

#ifdef __cplusplus
extern "C" {
#endif


/** \file include/FLAC/file_decoder.h
 *
 *  \brief
 *  This module contains the functions which implement the file
 *  decoder.
 *
 *  See the detailed documentation in the
 *  \link flac_file_decoder file decoder \endlink module.
 */

/** \defgroup flac_file_decoder FLAC/file_decoder.h: file decoder interface
 *  \ingroup flac_decoder
 *
 *  \brief
 *  This module contains the functions which implement the file
 *  decoder.
 *
 * The basic usage of this decoder is as follows:
 * - The program creates an instance of a decoder using
 *   FLAC__file_decoder_new().
 * - The program overrides the default settings and sets callbacks for
 *   writing, error reporting, and metadata reporting using
 *   FLAC__file_decoder_set_*() functions.
 * - The program initializes the instance to validate the settings and
 *   prepare for decoding using FLAC__file_decoder_init().
 * - The program calls the FLAC__file_decoder_process_*() functions
 *   to decode data, which subsequently calls the callbacks.
 * - The program finishes the decoding with FLAC__file_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__file_decoder_delete().
 *
 * The file decoder is a trivial wrapper around the
 * \link flac_seekable_stream_decoder seekable stream decoder \endlink
 * meant to simplfy the process of decoding from a standard file.  The
 * file decoder supplies all but the Write/Metadata/Error callbacks.
 * The user needs only to provide the path to the file and the file
 * decoder handles the rest.
 *
 * Like the seekable stream decoder, seeking is exposed through the
 * FLAC__file_decoder_seek_absolute() method.  At any point after the file
 * decoder has been initialized, the user can call this function to seek to
 * an exact sample within the file.  Subsequently, the first time the write
 * callback is called it will be passed a (possibly partial) block starting
 * at that sample.
 *
 * The file decoder also inherits MD5 signature checking from the seekable
 * stream decoder.  If this is turned on before initialization,
 * FLAC__file_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 if there is no signature in the STREAMINFO
 * block or when a seek is attempted.
 *
 * Make sure to read the detailed descriptions of the
 * \link flac_seekable_stream_decoder seekable stream decoder module \endlink
 * and \link flac_stream_decoder stream decoder module \endlink
 * since the file decoder inherits much of its behavior from them.
 *
 * \note
 * The "set" functions may only be called when the decoder is in the
 * state FLAC__FILE_DECODER_UNINITIALIZED, i.e. after
 * FLAC__file_decoder_new() or FLAC__file_decoder_finish(), but
 * before FLAC__file_decoder_init().  If this is the case they will
 * return \c true, otherwise \c false.
 *
 * \note
 * FLAC__file_decoder_finish() resets all settings to the constructor
 * defaults, including the callbacks.
 *
 * \{
 */


/** State values for a FLAC__FileDecoder
 *
 *  The decoder's state can be obtained by calling FLAC__file_decoder_get_state().
 */
typedef enum {

	FLAC__FILE_DECODER_OK = 0,
	/**< The decoder is in the normal OK state. */

	FLAC__FILE_DECODER_END_OF_FILE,
	/**< The decoder has reached the end of the file. */

	FLAC__FILE_DECODER_ERROR_OPENING_FILE,
	/**< An error occurred opening the input file. */

	FLAC__FILE_DECODER_MEMORY_ALLOCATION_ERROR,
	/**< An error occurred allocating memory. */

	FLAC__FILE_DECODER_SEEK_ERROR,
	/**< An error occurred while seeking. */

	FLAC__FILE_DECODER_SEEKABLE_STREAM_DECODER_ERROR,
	/**< An error occurred in the underlying seekable stream decoder. */

	FLAC__FILE_DECODER_ALREADY_INITIALIZED,
	/**< FLAC__file_decoder_init() was called when the decoder was already
	 * initialized, usually because FLAC__file_decoder_finish() was not
	 * called.
	 */

	FLAC__FILE_DECODER_INVALID_CALLBACK,
	/**< FLAC__file_decoder_init() was called without all callbacks
	 * being set.
	 */

	FLAC__FILE_DECODER_UNINITIALIZED
	/**< The decoder is in the uninitialized state. */

} FLAC__FileDecoderState;

/** Maps a FLAC__FileDecoderState to a C string.
 *
 *  Using a FLAC__FileDecoderState as the index to this array
 *  will give the string equivalent.  The contents should not be modified.
 */
extern FLAC_API const char * const FLAC__FileDecoderStateString[];


/***********************************************************************
 *
 * class FLAC__FileDecoder : public FLAC__StreamDecoder
 *
 ***********************************************************************/

struct FLAC__FileDecoderProtected;
struct FLAC__FileDecoderPrivate;
/** The opaque structure definition for the file decoder type.  See the
 *  \link flac_file_decoder file decoder module \endlink for a detailed
 *  description.
 */
typedef struct {
	struct FLAC__FileDecoderProtected *protected_; /* avoid the C++ keyword 'protected' */
	struct FLAC__FileDecoderPrivate *private_; /* avoid the C++ keyword 'private' */
} FLAC__FileDecoder;

/** Signature for the write callback.
 *  See FLAC__file_decoder_set_write_callback()
 *  and FLAC__SeekableStreamDecoderWriteCallback for more info.
 *
 * \param  decoder  The decoder instance calling the callback.
 * \param  frame    The description of the decoded frame.
 * \param  buffer   An array of pointers to decoded channels of data.
 * \param  client_data  The callee's client data set through
 *                      FLAC__file_decoder_set_client_data().
 * \retval FLAC__StreamDecoderWriteStatus
 *    The callee's return status.
 */
typedef FLAC__StreamDecoderWriteStatus (*FLAC__FileDecoderWriteCallback)(const FLAC__FileDecoder *decoder, const FLAC__Frame *frame, const FLAC__int32 * const buffer[], void *client_data);

/** Signature for the metadata callback.
 *  See FLAC__file_decoder_set_metadata_callback()
 *  and FLAC__SeekableStreamDecoderMetadataCallback for more info.
 *
 * \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__file_decoder_set_client_data().
 */
typedef void (*FLAC__FileDecoderMetadataCallback)(const FLAC__FileDecoder *decoder, const FLAC__StreamMetadata *metadata, void *client_data);

/** Signature for the error callback.
 *  See FLAC__file_decoder_set_error_callback()
 *  and FLAC__SeekableStreamDecoderErrorCallback for more info.
 *
 * \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__file_decoder_set_client_data().
 */
typedef void (*FLAC__FileDecoderErrorCallback)(const FLAC__FileDecoder *decoder, FLAC__StreamDecoderErrorStatus status, void *client_data);


/***********************************************************************
 *
 * Class constructor/destructor
 *
 ***********************************************************************/

/** Create a new file decoder instance.  The instance is created with
 *  default settings; see the individual FLAC__file_decoder_set_*()
 *  functions for each setting's default.
 *
 * \retval FLAC__FileDecoder*
 *    \c NULL if there was an error allocating memory, else the new instance.
 */
FLAC_API FLAC__FileDecoder *FLAC__file_decoder_new();

/** 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__file_decoder_delete(FLAC__FileDecoder *decoder);


/***********************************************************************
 *
 * Public class method prototypes
 *
 ***********************************************************************/

/** Set the "MD5 signature checking" flag.
 *  This is inherited from FLAC__SeekableStreamDecoder; see
 *  FLAC__seekable_stream_decoder_set_md5_checking().
 *
 * \default \c false
 * \param  decoder  A decoder instance to set.
 * \param  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__file_decoder_set_md5_checking(FLAC__FileDecoder *decoder, FLAC__bool value);

/** Set the input file name to decode.
 *
 * \default \c "-"
 * \param  decoder  A decoder instance to set.
 * \param  value    The input file name, or "-" for \c stdin.
 * \assert
 *    \code decoder != NULL \endcode
 *    \code value != NULL \endcode
 * \retval FLAC__bool
 *    \c false if the decoder is already initialized, or there was a memory
 *    allocation error, else \c true.
 */
FLAC_API FLAC__bool FLAC__file_decoder_set_filename(FLAC__FileDecoder *decoder, const char *value);

/** Set the write callback.
 *  This is inherited from FLAC__SeekableStreamDecoder; see
 *  FLAC__seekable_stream_decoder_set_write_callback().
 *
 * \note
 * The callback is mandatory and must be set before initialization.
 *
 * \default \c NULL
 * \param  decoder  A decoder instance to set.
 * \param  value    See above.
 * \assert
 *    \code decoder != NULL \endcode
 *    \code value != NULL \endcode
 * \retval FLAC__bool
 *    \c false if the decoder is already initialized, else \c true.
 */
FLAC_API FLAC__bool FLAC__file_decoder_set_write_callback(FLAC__FileDecoder *decoder, FLAC__FileDecoderWriteCallback value);

/** Set the metadata callback.
 *  This is inherited from FLAC__SeekableStreamDecoder; see
 *  FLAC__seekable_stream_decoder_set_metadata_callback().
 *
 * \note
 * The callback is mandatory and must be set before initialization.
 *
 * \default \c NULL
 * \param  decoder  A decoder instance to set.
 * \param  value    See above.
 * \assert
 *    \code decoder != NULL \endcode
 *    \code value != NULL \endcode
 * \retval FLAC__bool
 *    \c false if the decoder is already initialized, else \c true.
 */
FLAC_API FLAC__bool FLAC__file_decoder_set_metadata_callback(FLAC__FileDecoder *decoder, FLAC__FileDecoderMetadataCallback value);

/** Set the error callback.
 *  This is inherited from FLAC__SeekableStreamDecoder; see
 *  FLAC__seekable_stream_decoder_set_error_callback().
 *
 * \note
 * The callback is mandatory and must be set before initialization.
 *
 * \default \c NULL
 * \param  decoder  A decoder instance to set.
 * \param  value    See above.
 * \assert
 *    \code decoder != NULL \endcode
 *    \code value != NULL \endcode
 * \retval FLAC__bool
 *    \c false if the decoder is already initialized, else \c true.
 */
FLAC_API FLAC__bool FLAC__file_decoder_set_error_callback(FLAC__FileDecoder *decoder, FLAC__FileDecoderErrorCallback value);

/** Set the client data to be passed back to callbacks.