mpd/src/volume.c
2011-01-29 10:13:54 +01:00

147 lines
3.2 KiB
C

/*
* Copyright (C) 2003-2011 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.
*/
#include "config.h"
#include "volume.h"
#include "conf.h"
#include "player_control.h"
#include "idle.h"
#include "pcm_volume.h"
#include "output_all.h"
#include "mixer_control.h"
#include "mixer_all.h"
#include "mixer_type.h"
#include "event_pipe.h"
#include <glib.h>
#include <assert.h>
#include <math.h>
#include <string.h>
#include <stdlib.h>
#undef G_LOG_DOMAIN
#define G_LOG_DOMAIN "volume"
#define SW_VOLUME_STATE "sw_volume: "
static unsigned volume_software_set = 100;
/** the cached hardware mixer value; invalid if negative */
static int last_hardware_volume = -1;
/** the age of #last_hardware_volume */
static GTimer *hardware_volume_timer;
/**
* Handler for #PIPE_EVENT_MIXER.
*/
static void
mixer_event_callback(void)
{
/* flush the hardware volume cache */
last_hardware_volume = -1;
/* notify clients */
idle_add(IDLE_MIXER);
}
void volume_finish(void)
{
g_timer_destroy(hardware_volume_timer);
}
void volume_init(void)
{
hardware_volume_timer = g_timer_new();
event_pipe_register(PIPE_EVENT_MIXER, mixer_event_callback);
}
int volume_level_get(void)
{
assert(hardware_volume_timer != NULL);
if (last_hardware_volume >= 0 &&
g_timer_elapsed(hardware_volume_timer, NULL) < 1.0)
/* throttle access to hardware mixers */
return last_hardware_volume;
last_hardware_volume = mixer_all_get_volume();
g_timer_start(hardware_volume_timer);
return last_hardware_volume;
}
static bool software_volume_change(unsigned volume)
{
assert(volume <= 100);
volume_software_set = volume;
mixer_all_set_software_volume(volume);
return true;
}
static bool hardware_volume_change(unsigned volume)
{
/* reset the cache */
last_hardware_volume = -1;
return mixer_all_set_volume(volume);
}
bool volume_level_change(unsigned volume)
{
assert(volume <= 100);
volume_software_set = volume;
idle_add(IDLE_MIXER);
return hardware_volume_change(volume);
}
bool
read_sw_volume_state(const char *line)
{
char *end = NULL;
long int sv;
if (!g_str_has_prefix(line, SW_VOLUME_STATE))
return false;
line += sizeof(SW_VOLUME_STATE) - 1;
sv = strtol(line, &end, 10);
if (*end == 0 && sv >= 0 && sv <= 100)
software_volume_change(sv);
else
g_warning("Can't parse software volume: %s\n", line);
return true;
}
void save_sw_volume_state(FILE *fp)
{
fprintf(fp, SW_VOLUME_STATE "%u\n", volume_software_set);
}
unsigned
sw_volume_state_get_hash(void)
{
return volume_software_set;
}