alsa-lib/test/mixer.c

#include <stdio.h>
#include <string.h>
#include "../include/asoundlib.h"

static void mixer_test(int card, int device)
{
	int err;
	void *handle;
	snd_mixer_info_t info;

	if ((err = snd_mixer_open(&handle, card, device)) < 0) {
		printf("Mixer open error: %s\n", snd_strerror(err));
		return;
	}
	printf("Mixer %i/%i open ok...\n", card, device);
	if ((err = snd_mixer_info(handle, &info)) < 0) {
		printf("Mixer info error: %s\n", snd_strerror(err));
		return;
	}
	printf("  Info:\n");
	printf("    type - %i\n", info.type);
	printf("    elements - %i\n", info.elements);
	printf("    groups - %i\n", info.groups);
	printf("    switches - %i\n", info.switches);
	printf("    attribute - 0x%x\n", info.attribute);
	printf("    id - '%s'\n", info.id);
	printf("    name - '%s'\n", info.name);
	snd_mixer_close(handle);
}

void main(void)
{
	int idx, idx1, cards, err;
	void *handle;
	struct snd_ctl_hw_info info;

	cards = snd_cards();
	printf("Detected %i soundcard%s...\n", cards, cards > 1 ? "s" : "");
	if (cards <= 0) {
		printf("Giving up...\n");
		return;
	}
	for (idx = 0; idx < cards; idx++) {
		if ((err = snd_ctl_open(&handle, idx)) < 0) {
			printf("Open error: %s\n", snd_strerror(err));
			continue;
		}
		if ((err = snd_ctl_hw_info(handle, &info)) < 0) {
			printf("HW info error: %s\n", snd_strerror(err));
			continue;
		}
		for (idx1 = 0; idx1 < info.mixerdevs; idx1++)
			mixer_test(idx, idx1);
		snd_ctl_close(handle);
	}
}