metadata_iterators.c

wince下著名的视频播放器源码

/* libFLAC - Free Lossless Audio Codec library
 * Copyright (C) 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.
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "private/metadata.h"

#include "FLAC/assert.h"
#include "FLAC/file_decoder.h"

#ifdef max
#undef max
#endif
#define max(a,b) ((a)>(b)?(a):(b))
#ifdef min
#undef min
#endif
#define min(a,b) ((a)<(b)?(a):(b))


/****************************************************************************
 *
 * Local function declarations
 *
 ***************************************************************************/

static void pack_uint32_(FLAC__uint32 val, FLAC__byte *b, unsigned bytes);
static void pack_uint32_little_endian_(FLAC__uint32 val, FLAC__byte *b, unsigned bytes);
static void pack_uint64_(FLAC__uint64 val, FLAC__byte *b, unsigned bytes);
static FLAC__uint32 unpack_uint32_(FLAC__byte *b, unsigned bytes);
static FLAC__uint32 unpack_uint32_little_endian_(FLAC__byte *b, unsigned bytes);
static FLAC__uint64 unpack_uint64_(FLAC__byte *b, unsigned bytes);

static FLAC__bool read_metadata_block_header_(FLAC__Metadata_SimpleIterator *iterator);
static FLAC__bool read_metadata_block_data_(FLAC__Metadata_SimpleIterator *iterator, FLAC__StreamMetadata *block);
static FLAC__bool read_metadata_block_header_cb_(FLAC__IOHandle handle, FLAC__IOCallback_Read read_cb, FLAC__bool *is_last, FLAC__MetadataType *type, unsigned *length);
static FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_cb_(FLAC__IOHandle handle, FLAC__IOCallback_Read read_cb, FLAC__IOCallback_Seek seek_cb, FLAC__StreamMetadata *block);
static FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_streaminfo_cb_(FLAC__IOHandle handle, FLAC__IOCallback_Read read_cb, FLAC__StreamMetadata_StreamInfo *block);
static FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_padding_cb_(FLAC__IOHandle handle, FLAC__IOCallback_Seek seek_cb, FLAC__StreamMetadata_Padding *block, unsigned block_length);
static FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_application_cb_(FLAC__IOHandle handle, FLAC__IOCallback_Read read_cb, FLAC__StreamMetadata_Application *block, unsigned block_length);
static FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_seektable_cb_(FLAC__IOHandle handle, FLAC__IOCallback_Read read_cb, FLAC__StreamMetadata_SeekTable *block, unsigned block_length);
static FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_vorbis_comment_entry_cb_(FLAC__IOHandle handle, FLAC__IOCallback_Read read_cb, FLAC__StreamMetadata_VorbisComment_Entry *entry);
static FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_vorbis_comment_cb_(FLAC__IOHandle handle, FLAC__IOCallback_Read read_cb, FLAC__StreamMetadata_VorbisComment *block);
static FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_cuesheet_track_cb_(FLAC__IOHandle handle, FLAC__IOCallback_Read read_cb, FLAC__StreamMetadata_CueSheet_Track *track);
static FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_cuesheet_cb_(FLAC__IOHandle handle, FLAC__IOCallback_Read read_cb, FLAC__StreamMetadata_CueSheet *block);
static FLAC__Metadata_SimpleIteratorStatus read_metadata_block_data_unknown_cb_(FLAC__IOHandle handle, FLAC__IOCallback_Read read_cb, FLAC__StreamMetadata_Unknown *block, unsigned block_length);

static FLAC__bool write_metadata_block_header_(FILE *file, FLAC__Metadata_SimpleIteratorStatus *status, const FLAC__StreamMetadata *block);
static FLAC__bool write_metadata_block_data_(FILE *file, FLAC__Metadata_SimpleIteratorStatus *status, const FLAC__StreamMetadata *block);
static FLAC__bool write_metadata_block_header_cb_(FLAC__IOHandle handle, FLAC__IOCallback_Write write_cb, const FLAC__StreamMetadata *block);
static FLAC__bool write_metadata_block_data_cb_(FLAC__IOHandle handle, FLAC__IOCallback_Write write_cb, const FLAC__StreamMetadata *block);
static FLAC__bool write_metadata_block_data_streaminfo_cb_(FLAC__IOHandle handle, FLAC__IOCallback_Write write_cb, const FLAC__StreamMetadata_StreamInfo *block);
static FLAC__bool write_metadata_block_data_padding_cb_(FLAC__IOHandle handle, FLAC__IOCallback_Write write_cb, const FLAC__StreamMetadata_Padding *block, unsigned block_length);
static FLAC__bool write_metadata_block_data_application_cb_(FLAC__IOHandle handle, FLAC__IOCallback_Write write_cb, const FLAC__StreamMetadata_Application *block, unsigned block_length);
static FLAC__bool write_metadata_block_data_seektable_cb_(FLAC__IOHandle handle, FLAC__IOCallback_Write write_cb, const FLAC__StreamMetadata_SeekTable *block);
static FLAC__bool write_metadata_block_data_vorbis_comment_cb_(FLAC__IOHandle handle, FLAC__IOCallback_Write write_cb, const FLAC__StreamMetadata_VorbisComment *block);
static FLAC__bool write_metadata_block_data_cuesheet_cb_(FLAC__IOHandle handle, FLAC__IOCallback_Write write_cb, const FLAC__StreamMetadata_CueSheet *block);
static FLAC__bool write_metadata_block_data_unknown_cb_(FLAC__IOHandle handle, FLAC__IOCallback_Write write_cb, const FLAC__StreamMetadata_Unknown *block, unsigned block_length);

static FLAC__bool write_metadata_block_stationary_(FLAC__Metadata_SimpleIterator *iterator, const FLAC__StreamMetadata *block);
static FLAC__bool write_metadata_block_stationary_with_padding_(FLAC__Metadata_SimpleIterator *iterator, FLAC__StreamMetadata *block, unsigned padding_length, FLAC__bool padding_is_last);
static FLAC__bool rewrite_whole_file_(FLAC__Metadata_SimpleIterator *iterator, FLAC__StreamMetadata *block, FLAC__bool append);

static void simple_iterator_push_(FLAC__Metadata_SimpleIterator *iterator);
static FLAC__bool simple_iterator_pop_(FLAC__Metadata_SimpleIterator *iterator);

static unsigned seek_to_first_metadata_block_cb_(FLAC__IOHandle handle, FLAC__IOCallback_Read read_cb, FLAC__IOCallback_Seek seek_cb);
static unsigned seek_to_first_metadata_block_(FILE *f);

static FLAC__bool simple_iterator_copy_file_prefix_(FLAC__Metadata_SimpleIterator *iterator, FILE **tempfile, char **tempfilename, FLAC__bool append);
static FLAC__bool simple_iterator_copy_file_postfix_(FLAC__Metadata_SimpleIterator *iterator, FILE **tempfile, char **tempfilename, int fixup_is_last_code, long fixup_is_last_flag_offset, FLAC__bool backup);

static FLAC__bool copy_n_bytes_from_file_(FILE *file, FILE *tempfile, unsigned bytes/*@@@ 4G limit*/, FLAC__Metadata_SimpleIteratorStatus *status);
static FLAC__bool copy_n_bytes_from_file_cb_(FLAC__IOHandle handle, FLAC__IOCallback_Read read_cb, FLAC__IOHandle temp_handle, FLAC__IOCallback_Write temp_write_cb, unsigned bytes/*@@@ 4G limit*/, FLAC__Metadata_SimpleIteratorStatus *status);
static FLAC__bool copy_remaining_bytes_from_file_(FILE *file, FILE *tempfile, FLAC__Metadata_SimpleIteratorStatus *status);
static FLAC__bool copy_remaining_bytes_from_file_cb_(FLAC__IOHandle handle, FLAC__IOCallback_Read read_cb, FLAC__IOCallback_Eof eof_cb, FLAC__IOHandle temp_handle, FLAC__IOCallback_Write temp_write_cb, FLAC__Metadata_SimpleIteratorStatus *status);

static FLAC__bool open_tempfile_(const char *filename, const char *tempfile_path_prefix, FILE **tempfile, char **tempfilename, FLAC__Metadata_SimpleIteratorStatus *status);
static FLAC__bool transport_tempfile_(const char *filename, FILE **tempfile, char **tempfilename, FLAC__Metadata_SimpleIteratorStatus *status);
static void cleanup_tempfile_(FILE **tempfile, char **tempfilename);

static FLAC__bool get_file_stats_(const char *filename, struct stat *stats);
static void set_file_stats_(const char *filename, struct stat *stats);

static int fseek_wrapper_(FLAC__IOHandle handle, FLAC__int64 offset, int whence);
static FLAC__int64 ftell_wrapper_(FLAC__IOHandle handle);

static FLAC__Metadata_ChainStatus get_equivalent_status_(FLAC__Metadata_SimpleIteratorStatus status);


#ifdef FLAC__VALGRIND_TESTING
static size_t local__fwrite(const void *ptr, size_t size, size_t nmemb, FILE *stream)
{
	size_t ret = fwrite(ptr, size, nmemb, stream);
	if(!ferror(stream))
		fflush(stream);
	return ret;
}
#else
#define local__fwrite fwrite
#endif

/****************************************************************************
 *
 * Level 1 implementation
 *
 ***************************************************************************/

#define SIMPLE_ITERATOR_MAX_PUSH_DEPTH (1+4)
/* 1 for initial offset, +4 for our own personal use */

struct FLAC__Metadata_SimpleIterator {
	FILE *file;
	char *filename, *tempfile_path_prefix;
	FLAC__bool is_writable;
	FLAC__Metadata_SimpleIteratorStatus status;
	/*@@@ 2G limits here because of the offset type: */
	long offset[SIMPLE_ITERATOR_MAX_PUSH_DEPTH];
	long first_offset; /* this is the offset to the STREAMINFO block */
	unsigned depth;
	/* this is the metadata block header of the current block we are pointing to: */
	FLAC__bool is_last;
	FLAC__MetadataType type;
	unsigned length;
};

FLAC_API const char * const FLAC__Metadata_SimpleIteratorStatusString[] = {
	"FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK",
	"FLAC__METADATA_SIMPLE_ITERATOR_STATUS_ILLEGAL_INPUT",
	"FLAC__METADATA_SIMPLE_ITERATOR_STATUS_ERROR_OPENING_FILE",
	"FLAC__METADATA_SIMPLE_ITERATOR_STATUS_NOT_A_FLAC_FILE",
	"FLAC__METADATA_SIMPLE_ITERATOR_STATUS_NOT_WRITABLE",
	"FLAC__METADATA_SIMPLE_ITERATOR_STATUS_BAD_METADATA",
	"FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR",
	"FLAC__METADATA_SIMPLE_ITERATOR_STATUS_SEEK_ERROR",
	"FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR",
	"FLAC__METADATA_SIMPLE_ITERATOR_STATUS_RENAME_ERROR",
	"FLAC__METADATA_SIMPLE_ITERATOR_STATUS_UNLINK_ERROR",
	"FLAC__METADATA_SIMPLE_ITERATOR_STATUS_MEMORY_ALLOCATION_ERROR",
	"FLAC__METADATA_SIMPLE_ITERATOR_STATUS_INTERNAL_ERROR"
};


FLAC_API FLAC__Metadata_SimpleIterator *FLAC__metadata_simple_iterator_new()
{
	FLAC__Metadata_SimpleIterator *iterator = (FLAC__Metadata_SimpleIterator*)calloc(1, sizeof(FLAC__Metadata_SimpleIterator));

	if(0 != iterator) {
		iterator->file = 0;
		iterator->filename = 0;
		iterator->tempfile_path_prefix = 0;
		iterator->is_writable = false;
		iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK;
		iterator->first_offset = iterator->offset[0] = -1;
		iterator->depth = 0;
	}

	return iterator;
}

static void simple_iterator_free_guts_(FLAC__Metadata_SimpleIterator *iterator)
{
	FLAC__ASSERT(0 != iterator);

	if(0 != iterator->file) {
		fclose(iterator->file);
		iterator->file = 0;
	}
	if(0 != iterator->filename) {
		free(iterator->filename);
		iterator->filename = 0;
	}
	if(0 != iterator->tempfile_path_prefix) {
		free(iterator->tempfile_path_prefix);
		iterator->tempfile_path_prefix = 0;
	}
}

FLAC_API void FLAC__metadata_simple_iterator_delete(FLAC__Metadata_SimpleIterator *iterator)
{
	FLAC__ASSERT(0 != iterator);

	simple_iterator_free_guts_(iterator);
	free(iterator);
}

FLAC_API FLAC__Metadata_SimpleIteratorStatus FLAC__metadata_simple_iterator_status(FLAC__Metadata_SimpleIterator *iterator)
{
	FLAC__Metadata_SimpleIteratorStatus status;

	FLAC__ASSERT(0 != iterator);

	status = iterator->status;
	iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_OK;
	return status;
}

static FLAC__bool simple_iterator_prime_input_(FLAC__Metadata_SimpleIterator *iterator, FLAC__bool read_only)
{
	unsigned ret;

	FLAC__ASSERT(0 != iterator);

	if(read_only || 0 == (iterator->file = fopen(iterator->filename, "r+b"))) {
		iterator->is_writable = false;
		if(read_only) {
			if(0 == (iterator->file = fopen(iterator->filename, "rb"))) {
				iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_ERROR_OPENING_FILE;
				return false;
			}
		}
		else {
			iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_ERROR_OPENING_FILE;
			return false;
		}
	}
	else {
		iterator->is_writable = true;
	}

	ret = seek_to_first_metadata_block_(iterator->file);
	switch(ret) {
		case 0:
			iterator->depth = 0;
			iterator->first_offset = iterator->offset[iterator->depth] = ftell(iterator->file);
			return read_metadata_block_header_(iterator);
		case 1:
			iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR;
			return false;
		case 2:
			iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_SEEK_ERROR;
			return false;
		case 3:
			iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_NOT_A_FLAC_FILE;
			return false;
		default:
			FLAC__ASSERT(0);
			return false;
	}
}

#if 0
@@@ If we decide to finish implementing this, put this comment back in metadata.h
/*
 * The 'tempfile_path_prefix' allows you to specify a directory where
 * tempfiles should go.  Remember that if your metadata edits cause the
 * FLAC file to grow, the entire file will have to be rewritten.  If
 * 'tempfile_path_prefix' is NULL, the temp file will be written in the
 * same directory as the original FLAC file.  This makes replacing the
 * original with the tempfile fast but requires extra space in the same
 * partition for the tempfile.  If space is a problem, you can pass a
 * directory name belonging to a different partition in
 * 'tempfile_path_prefix'.  Note that you should use the forward slash
 * '/' as the directory separator.  A trailing slash is not needed; it
 * will be added automatically.
 */
FLAC__bool FLAC__metadata_simple_iterator_init(FLAC__Metadata_SimpleIterator *iterator, const char *filename, FLAC__bool preserve_file_stats, const char *tempfile_path_prefix);
#endif

FLAC_API FLAC__bool FLAC__metadata_simple_iterator_init(FLAC__Metadata_SimpleIterator *iterator, const char *filename, FLAC__bool read_only, FLAC__bool preserve_file_stats)
{
	const char *tempfile_path_prefix = 0; /*@@@ search for comments near 'rename(...)' for what it will take to finish implementing this */

	FLAC__ASSERT(0 != iterator);
	FLAC__ASSERT(0 != filename);

	simple_iterator_free_guts_(iterator);

	if(0 == (iterator->filename = _strdup(filename))) {
		iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_MEMORY_ALLOCATION_ERROR;
		return false;
	}
	if(0 != tempfile_path_prefix && 0 == (iterator->tempfile_path_prefix = _strdup(tempfile_path_prefix))) {
		iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_MEMORY_ALLOCATION_ERROR;
		return false;
	}

	return simple_iterator_prime_input_(iterator, read_only);
}

FLAC_API FLAC__bool FLAC__metadata_simple_iterator_is_writable(const FLAC__Metadata_SimpleIterator *iterator)
{
	FLAC__ASSERT(0 != iterator);
	FLAC__ASSERT(0 != iterator->file);

	return iterator->is_writable;
}

FLAC_API FLAC__bool FLAC__metadata_simple_iterator_next(FLAC__Metadata_SimpleIterator *iterator)
{
	FLAC__ASSERT(0 != iterator);
	FLAC__ASSERT(0 != iterator->file);

	if(iterator->is_last)
		return false;

	if(0 != fseek(iterator->file, iterator->length, SEEK_CUR)) {
		iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_SEEK_ERROR;
		return false;
	}

	iterator->offset[iterator->depth] = ftell(iterator->file);

	return read_metadata_block_header_(iterator);
}

FLAC_API FLAC__bool FLAC__metadata_simple_iterator_prev(FLAC__Metadata_SimpleIterator *iterator)
{
	long this_offset;

	FLAC__ASSERT(0 != iterator);
	FLAC__ASSERT(0 != iterator->file);

	if(iterator->offset[iterator->depth] == iterator->first_offset)
		return false;

	if(0 != fseek(iterator->file, iterator->first_offset, SEEK_SET)) {
		iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_SEEK_ERROR;
		return false;
	}
	this_offset = iterator->first_offset;
	if(!read_metadata_block_header_(iterator))
		return false;

	/* we ignore any error from ftell() and catch it in fseek() */
	while(ftell(iterator->file) + (long)iterator->length < iterator->offset[iterator->depth]) {
		if(0 != fseek(iterator->file, iterator->length, SEEK_CUR)) {
			iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_SEEK_ERROR;
			return false;
		}
		this_offset = ftell(iterator->file);
		if(!read_metadata_block_header_(iterator))
			return false;
	}

	iterator->offset[iterator->depth] = this_offset;

	return true;
}

FLAC_API FLAC__MetadataType FLAC__metadata_simple_iterator_get_block_type(const FLAC__Metadata_SimpleIterator *iterator)
{
	FLAC__ASSERT(0 != iterator);
	FLAC__ASSERT(0 != iterator->file);