nomad.h

/*
 * Copyright 2008-2013 Various Authors
 * Copyright 2004 Timo Hirvonen
 *
 * 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, see <http://www.gnu.org/licenses/>.
 */

#ifndef CMUS_NOMAD_H
#define CMUS_NOMAD_H

#include <sys/types.h>

#ifndef __GNUC__
#include <unistd.h>
#endif

/* default callbacks use read, lseek, close */
struct nomad_callbacks {
	ssize_t (*read)(void *datasource, void *buffer, size_t count);
	off_t (*lseek)(void *datasource, off_t offset, int whence);
	int (*close)(void *datasource);
};

enum {
	XING_FRAMES = 0x00000001L,
	XING_BYTES  = 0x00000002L,
	XING_TOC    = 0x00000004L,
	XING_SCALE  = 0x00000008L
};

struct nomad_xing {
	unsigned int is_info : 1;
	unsigned int flags;
	unsigned int nr_frames;
	unsigned int bytes;
	unsigned int scale;
	unsigned char toc[100];
};

struct nomad_lame {
	char encoder[10];   /* 9 byte encoder name/version ("LAME3.97b") */
	int vbr_method;     /* VBR method */
	float peak;         /* replaygain peak */
	float trackGain;    /* replaygain track gain */
	float albumGain;    /* replaygain album gain */
	int encoderDelay;   /* # of added samples at start of mp3 */
	int encoderPadding; /* # of added samples at end of mp3 */
};

/* always 16-bit signed little-endian */
struct nomad_info {
	double duration;
	int sample_rate;
	int channels;
	int nr_frames;
	int layer;
	/* guessed */
	int vbr;
	/* guessed */
	int avg_bitrate;
	/* -1 if file not seekable */
	off_t filesize;
	unsigned int joint_stereo : 1;
	unsigned int dual_channel : 1;
};

enum {
	NOMAD_ERROR_SUCCESS,
	NOMAD_ERROR_ERRNO,
	NOMAD_ERROR_FILE_FORMAT
};

struct nomad;

/* -NOMAD_ERROR_ERRNO -NOMAD_ERROR_FILE_FORMAT */
int nomad_open_callbacks(struct nomad **nomadp, void *datasource,
		struct nomad_callbacks *cbs);

void nomad_close(struct nomad *nomad);

/* -NOMAD_ERROR_ERRNO */
int nomad_read(struct nomad *nomad, char *buffer, int count);

/* -NOMAD_ERROR_ERRNO */
int nomad_time_seek(struct nomad *nomad, double pos);

const struct nomad_xing *nomad_xing(struct nomad *nomad);
const struct nomad_lame *nomad_lame(struct nomad *nomad);
const struct nomad_info *nomad_info(struct nomad *nomad);
long nomad_current_bitrate(struct nomad *nomad);

#endif