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/*
* 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#ifndef MPD_MIXER_H
#define MPD_MIXER_H
#include "conf.h"
/*
* list of currently implemented mixers
*/
extern const struct mixer_plugin alsa_mixer;
extern const struct mixer_plugin oss_mixer;
struct mixer_plugin {
/**
* Alocates and configures a mixer device.
*/
struct mixer *(*init)(const struct config_param *param);
/**
* Finish and free mixer data
*/
void (*finish)(struct mixer *data);
/**
* Open mixer device
*/
bool (*open)(struct mixer *data);
/**
* Close mixer device
*/
void (*close)(struct mixer *data);
/**
* Reads the current volume.
*
* @return the current volume (0..100 including) or -1 on
* error
*/
int (*get_volume)(struct mixer *mixer);
/**
* Sets the volume.
*
* @param volume the new volume (0..100 including)
* @return true on success
*/
bool (*set_volume)(struct mixer *mixer, unsigned volume);
};
struct mixer {
const struct mixer_plugin *plugin;
};
static inline void
mixer_init(struct mixer *mixer, const struct mixer_plugin *plugin)
{
mixer->plugin = plugin;
}
struct mixer *
mixer_new(const struct mixer_plugin *plugin, const struct config_param *param);
void
mixer_free(struct mixer *mixer);
bool mixer_open(struct mixer *mixer);
void mixer_close(struct mixer *mixer);
static inline int
mixer_get_volume(struct mixer *mixer)
{
return mixer->plugin->get_volume(mixer);
}
static inline bool
mixer_set_volume(struct mixer *mixer, unsigned volume)
{
return mixer->plugin->set_volume(mixer, volume);
}
#endif
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