mpd/src/chunk.h
Avuton Olrich 0aee49bdf8 all: Update copyright header.
This updates the copyright header to all be the same, which is
pretty much an update of where to mail request for a copy of the GPL
and the years of the MPD project. This also puts all committers under
'The Music Player Project' umbrella. These entries should go
individually in the AUTHORS file, for consistancy.
2009-03-13 11:51:55 -07:00

125 lines
3.3 KiB
C

/*
* Copyright (C) 2003-2009 The Music Player Daemon Project
* http://www.musicpd.org
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#ifndef MPD_CHUNK_H
#define MPD_CHUNK_H
#ifndef NDEBUG
#include "audio_format.h"
#endif
#include <stdbool.h>
#include <stdint.h>
#include <stddef.h>
enum {
CHUNK_SIZE = 4096,
};
struct audio_format;
/**
* A chunk of music data. Its format is defined by the
* music_pipe_append() caller.
*/
struct music_chunk {
/** the next chunk in a linked list */
struct music_chunk *next;
/** number of bytes stored in this chunk */
uint16_t length;
/** current bit rate of the source file */
uint16_t bit_rate;
/** the time stamp within the song */
float times;
/**
* An optional tag associated with this chunk (and the
* following chunks); appears at song boundaries. The tag
* object is owned by this chunk, and must be freed when this
* chunk is deinitialized in music_chunk_free()
*/
struct tag *tag;
/** the data (probably PCM) */
char data[CHUNK_SIZE];
#ifndef NDEBUG
struct audio_format audio_format;
#endif
};
void
music_chunk_init(struct music_chunk *chunk);
void
music_chunk_free(struct music_chunk *chunk);
static inline bool
music_chunk_is_empty(const struct music_chunk *chunk)
{
return chunk->length == 0 && chunk->tag == NULL;
}
#ifndef NDEBUG
/**
* Checks if the audio format if the chunk is equal to the specified
* audio_format.
*/
bool
music_chunk_check_format(const struct music_chunk *chunk,
const struct audio_format *audio_format);
#endif
/**
* Prepares appending to the music chunk. Returns a buffer where you
* may write into. After you are finished, call music_chunk_expand().
*
* @param chunk the music_chunk object
* @param audio_format the audio format for the appended data; must
* stay the same for the life cycle of this chunk
* @param data_time the time within the song
* @param bit_rate the current bit rate of the source file
* @param max_length_r the maximum write length is returned here
* @return a writable buffer, or NULL if the chunk is full
*/
void *
music_chunk_write(struct music_chunk *chunk,
const struct audio_format *audio_format,
float data_time, uint16_t bit_rate,
size_t *max_length_r);
/**
* Increases the length of the chunk after the caller has written to
* the buffer returned by music_chunk_write().
*
* @param chunk the music_chunk object
* @param audio_format the audio format for the appended data; must
* stay the same for the life cycle of this chunk
* @param length the number of bytes which were appended
* @return true if the chunk is full
*/
bool
music_chunk_expand(struct music_chunk *chunk,
const struct audio_format *audio_format, size_t length);
#endif