• Max Kellermann's avatar
    output: use the software mixer plugin · 0275690b
    Max Kellermann authored
    Do all the software volume stuff inside each output thread, not in the
    player thread.  This allows one software mixer per output device, and
    also allows the user to configure the mixer type (hardware or
    software) for each audio output.
    
    This moves the global "mixer_type" setting into the "audio_output"
    section, deprecating the "mixer_enabled" flag.
    0275690b
output_init.c 5.34 KB
/*
 * 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.
 */

#include "output_control.h"
#include "output_api.h"
#include "output_internal.h"
#include "output_list.h"
#include "audio_parser.h"
#include "mixer_control.h"
#include "mixer_type.h"
#include "mixer_list.h"
#include "mixer/software_mixer_plugin.h"
#include "filter_plugin.h"
#include "filter_registry.h"
#include "filter/chain_filter_plugin.h"

#include <glib.h>

#include <assert.h>

#undef G_LOG_DOMAIN
#define G_LOG_DOMAIN "output"

#define AUDIO_OUTPUT_TYPE	"type"
#define AUDIO_OUTPUT_NAME	"name"
#define AUDIO_OUTPUT_FORMAT	"format"

static const struct audio_output_plugin *
audio_output_detect(GError **error)
{
	const struct audio_output_plugin *plugin;
	unsigned i;

	g_warning("Attempt to detect audio output device");

	audio_output_plugins_for_each(plugin, i) {
		if (plugin->test_default_device == NULL)
			continue;

		g_warning("Attempting to detect a %s audio device",
			  plugin->name);
		if (ao_plugin_test_default_device(plugin))
			return plugin;
	}

	g_set_error(error, audio_output_quark(), 0,
		    "Unable to detect an audio device");
	return NULL;
}

/**
 * Determines the mixer type which should be used for the specified
 * configuration block.
 *
 * This handles the deprecated options mixer_type (global) and
 * mixer_enabled, if the mixer_type setting is not configured.
 */
static enum mixer_type
audio_output_mixer_type(const struct config_param *param)
{
	/* read the local "mixer_type" setting */
	const char *p = config_get_block_string(param, "mixer_type", NULL);
	if (p != NULL)
		return mixer_type_parse(p);

	/* try the local "mixer_enabled" setting next (deprecated) */
	if (!config_get_block_bool(param, "mixer_enabled", true))
		return MIXER_TYPE_NONE;

	/* fall back to the global "mixer_type" setting (also
	   deprecated) */
	return mixer_type_parse(config_get_string("mixer_type", "hardware"));
}

static struct mixer *
audio_output_load_mixer(const struct config_param *param,
			const struct mixer_plugin *plugin,
			struct filter *filter_chain)
{
	struct mixer *mixer;

	switch (audio_output_mixer_type(param)) {
	case MIXER_TYPE_NONE:
	case MIXER_TYPE_UNKNOWN:
		return NULL;

	case MIXER_TYPE_HARDWARE:
		if (plugin == NULL)
			return NULL;

		return mixer_new(plugin, param);

	case MIXER_TYPE_SOFTWARE:
		mixer = mixer_new(&software_mixer_plugin, NULL);
		assert(mixer != NULL);

		filter_chain_append(filter_chain,
				    software_mixer_get_filter(mixer));
		return mixer;
	}

	assert(false);
	return NULL;
}

bool
audio_output_init(struct audio_output *ao, const struct config_param *param,
		  GError **error)
{
	const struct audio_output_plugin *plugin = NULL;

	if (param) {
		const char *p;

		p = config_get_block_string(param, AUDIO_OUTPUT_TYPE, NULL);
		if (p == NULL) {
			g_set_error(error, audio_output_quark(), 0,
				    "Missing \"type\" configuration");
			return false;
		}

		plugin = audio_output_plugin_get(p);
		if (plugin == NULL) {
			g_set_error(error, audio_output_quark(), 0,
				    "No such audio output plugin: %s", p);
			return false;
		}

		ao->name = config_get_block_string(param, AUDIO_OUTPUT_NAME,
						   NULL);
		if (ao->name == NULL) {
			g_set_error(error, audio_output_quark(), 0,
				    "Missing \"name\" configuration");
			return false;
		}

		p = config_get_block_string(param, AUDIO_OUTPUT_FORMAT,
						 NULL);
		ao->config_audio_format = p != NULL;
		if (p != NULL) {
			bool success =
				audio_format_parse(&ao->out_audio_format,
						   p, error);
			if (!success)
				return false;
		}
	} else {
		g_warning("No \"%s\" defined in config file\n",
			  CONF_AUDIO_OUTPUT);

		plugin = audio_output_detect(error);
		if (plugin == NULL)
			return false;

		g_message("Successfully detected a %s audio device",
			  plugin->name);

		ao->name = "default detected output";
		ao->config_audio_format = false;
	}

	ao->plugin = plugin;
	ao->enabled = config_get_block_bool(param, "enabled", true);
	ao->open = false;
	ao->fail_timer = NULL;

	/* set up the filter chain */

	ao->filter = filter_chain_new();
	assert(ao->filter != NULL);

	ao->thread = NULL;
	notify_init(&ao->notify);
	ao->command = AO_COMMAND_NONE;
	ao->mutex = g_mutex_new();

	ao->data = ao_plugin_init(plugin,
				  ao->config_audio_format
				  ? &ao->out_audio_format : NULL,
				  param, error);
	if (ao->data == NULL)
		return false;

	ao->mixer = audio_output_load_mixer(param, plugin->mixer_plugin,
					    ao->filter);

	/* the "convert" filter must be the last one in the chain */

	ao->convert_filter = filter_new(&convert_filter_plugin, NULL, NULL);
	assert(ao->convert_filter != NULL);

	filter_chain_append(ao->filter, ao->convert_filter);

	/* done */

	return true;
}