xref: /third_party/alsa-lib/test/pcm_min.c (revision d5ac70f0)
1/*
2 *  This extra small demo sends a random samples to your speakers.
3 */
4
5#include "../include/asoundlib.h"
6
7static char *device = "default";			/* playback device */
8unsigned char buffer[16*1024];				/* some random data */
9
10int main(void)
11{
12	int err;
13	unsigned int i;
14	snd_pcm_t *handle;
15	snd_pcm_sframes_t frames;
16
17	for (i = 0; i < sizeof(buffer); i++)
18		buffer[i] = random() & 0xff;
19
20	if ((err = snd_pcm_open(&handle, device, SND_PCM_STREAM_PLAYBACK, 0)) < 0) {
21		printf("Playback open error: %s\n", snd_strerror(err));
22		exit(EXIT_FAILURE);
23	}
24	if ((err = snd_pcm_set_params(handle,
25				      SND_PCM_FORMAT_U8,
26				      SND_PCM_ACCESS_RW_INTERLEAVED,
27				      1,
28				      48000,
29				      1,
30				      500000)) < 0) {	/* 0.5sec */
31		printf("Playback open error: %s\n", snd_strerror(err));
32		exit(EXIT_FAILURE);
33	}
34
35        for (i = 0; i < 16; i++) {
36		frames = snd_pcm_writei(handle, buffer, sizeof(buffer));
37		if (frames < 0)
38			frames = snd_pcm_recover(handle, frames, 0);
39		if (frames < 0) {
40			printf("snd_pcm_writei failed: %s\n", snd_strerror(frames));
41			break;
42		}
43		if (frames > 0 && frames < (long)sizeof(buffer))
44			printf("Short write (expected %li, wrote %li)\n", (long)sizeof(buffer), frames);
45	}
46
47	/* pass the remaining samples, otherwise they're dropped in close */
48	err = snd_pcm_drain(handle);
49	if (err < 0)
50		printf("snd_pcm_drain failed: %s\n", snd_strerror(err));
51	snd_pcm_close(handle);
52	return 0;
53}
54