mpd/src/output_state.c
Max Kellermann ecb118f1ed state_file: save only if something has changed
If nothing has changed since the last save, don't save the state
file.  Saving will spin up the hard drive, which is undesirable on
hosts where MPD is idling in background.
2009-10-08 15:22:39 +02:00

91 lines
2.0 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.
*/
/*
* Saving and loading the audio output states to/from the state file.
*
*/
#include "output_state.h"
#include "output_internal.h"
#include "output_all.h"
#include <glib.h>
#include <assert.h>
#include <stdlib.h>
#include <string.h>
#define AUDIO_DEVICE_STATE "audio_device_state:"
unsigned audio_output_state_version;
void
audio_output_state_save(FILE *fp)
{
unsigned n = audio_output_count();
assert(n > 0);
for (unsigned i = 0; i < n; ++i) {
const struct audio_output *ao = audio_output_get(i);
fprintf(fp, AUDIO_DEVICE_STATE "%d:%s\n",
ao->enabled, ao->name);
}
}
bool
audio_output_state_read(const char *line)
{
long value;
char *endptr;
const char *name;
struct audio_output *ao;
if (!g_str_has_prefix(line, AUDIO_DEVICE_STATE))
return false;
line += sizeof(AUDIO_DEVICE_STATE) - 1;
value = strtol(line, &endptr, 10);
if (*endptr != ':' || (value != 0 && value != 1))
return false;
if (value != 0)
/* state is "enabled": no-op */
return true;
name = endptr + 1;
ao = audio_output_find(name);
if (ao == NULL) {
g_debug("Ignoring device state for '%s'", name);
return true;
}
ao->enabled = false;
return true;
}
unsigned
audio_output_state_get_version(void)
{
return audio_output_state_version;
}