chiark - git - mdw - disorder/blame_incremental

... / ...

Commit	Line	Data
	1	/*
	2	* This file is part of DisOrder
	3	* Copyright (C) 2007 Richard Kettlewell
	4	*
	5	* This program is free software; you can redistribute it and/or modify
	6	* it under the terms of the GNU General Public License as published by
	7	* the Free Software Foundation; either version 2 of the License, or
	8	* (at your option) any later version.
	9	*
	10	* This program is distributed in the hope that it will be useful, but
	11	* WITHOUT ANY WARRANTY; without even the implied warranty of
	12	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	13	* General Public License for more details.
	14	*
	15	* You should have received a copy of the GNU General Public License
	16	* along with this program; if not, write to the Free Software
	17	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
	18	* USA
	19	*/
	20	/** @file lib/mixer.c
	21	* @brief Mixer support
	22	*/
	23
	24	#include <config.h>
	25	#include "types.h"
	26
	27	#include "configuration.h"
	28	#include "mixer.h"
	29	#include "log.h"
	30	#include "mem.h"
	31
	32	/** @brief Whether lack of volume support has been reported yet */
	33	static int none_reported;
	34
	35	/** @brief Get/set volume stub if volume control is not supported */
	36	static int none_get_set(int attribute((unused)) *left,
	37	int attribute((unused)) *right) {
	38	if(!none_reported) {
	39	error(0, "don't know how to get/set volume with this api");
	40	none_reported = 1;
	41	}
	42	return -1;
	43	}
	44
	45	/** @brief Stub mixer control */
	46	static const struct mixer mixer_none = {
	47	-1,
	48	none_get_set,
	49	none_get_set,
	50	"",
	51	""
	52	};
	53
	54	/** @brief Table of mixer definitions */
	55	static const struct mixer *mixers[] = {
	56	#if HAVE_SYS_SOUNDCARD_H
	57	&mixer_oss,
	58	#endif
	59	#if HAVE_ALSA_ASOUNDLIB_H
	60	&mixer_alsa,
	61	#endif
	62	&mixer_none /* make sure array is never empty */
	63	};
	64
	65	/** @brief Number of mixer definitions */
	66	#define NMIXERS (sizeof mixers / sizeof *mixers)
	67
	68	/** @brief Find the mixer definition */
	69	static const struct mixer *find_mixer(int api) {
	70	size_t n;
	71
	72	if(api == -1)
	73	api = config->api;
	74	for(n = 0; n < NMIXERS; ++n)
	75	if(mixers[n]->api == api)
	76	return mixers[n];
	77	return &mixer_none;
	78	}
	79
	80	/** @brief Return true if we know how to drive the mixer
	81	* @param api Sound api or -1 for default
	82	* @return true if suppored, false otherwise
	83	*/
	84	int mixer_supported(int api) {
	85	const struct mixer *const m = find_mixer(api);
	86	return m != &mixer_none;
	87	}
	88
	89	/** @brief Get/set volume
	90	* @param api Sound api or -1 for default
	91	* @param left Left channel level, 0-100
	92	* @param right Right channel level, 0-100
	93	* @param set Set volume if non-0
	94	* @return 0 on success, non-0 on error
	95	*
	96	* If getting the volume then @p left and @p right are filled in.
	97	*
	98	* If setting the volume then the target levels are read from @p left and
	99	* @p right, and the actual level set is stored in them.
	100	*/
	101	int mixer_control(int api, int left, int right, int set) {
	102	const struct mixer *const m = find_mixer(api);
	103
	104	/* We impose defaults bizarrely late, but this has the advantage of
	105	* not making everything depend on sound libraries */
	106	if(!config->mixer)
	107	config->mixer = xstrdup(m->device);
	108	if(!config->channel)
	109	config->channel = xstrdup(m->channel);
	110	if(set)
	111	return m->set(left, right);
	112	else
	113	return m->get(left, right);
	114	}
	115
	116	/*
	117	Local Variables:
	118	c-basic-offset:2
	119	comment-column:40
	120	End:
	121	*/