/* to build:
 *   $ gcc -Wall -o alsa-test alsa-test.c -lasound
 */

#include <alsa/asoundlib.h>

int main(int argc, char **argv)
{
    snd_pcm_t *pcm;
    snd_pcm_hw_params_t *hw_params;
    unsigned int rate;
    snd_pcm_uframes_t bytes;
    int err;

    if((err = snd_pcm_open(&pcm, "example", SND_PCM_STREAM_PLAYBACK, 0) < 0)){
        fprintf(stderr, "snd_pcm_open: %d (%s)\n", err, snd_strerror(err));
        return 1;
    }

    if((err = snd_pcm_hw_params_malloc(&hw_params)) < 0){
        fprintf(stderr, "snd_pcm_hw_params_malloc: %d (%s)\n", err, snd_strerror(err));
        return 1;
    }

    if((err = snd_pcm_hw_params_any(pcm, hw_params) < 0)){
        fprintf(stderr, "snd_pcm_hw_params_any: %d (%s)\n", err, snd_strerror(err));
        return 1;
    }

    if((err = snd_pcm_hw_params_set_access(pcm, hw_params,
                    SND_PCM_ACCESS_RW_INTERLEAVED) < 0)){
        fprintf(stderr, "snd_pcm_hw_params_set_access: %d (%s)\n", err, snd_strerror(err));
        return 1;
    }

    if((err = snd_pcm_hw_params_set_format(pcm, hw_params,
                    SND_PCM_FORMAT_S16_LE) < 0)){
        fprintf(stderr, "snd_pcm_hw_params_set_format: %d (%s)\n", err, snd_strerror(err));
        return 1;
    }

    rate = 44100;
    if((err = snd_pcm_hw_params_set_rate_near(pcm, hw_params, &rate, NULL)) < 0){
        fprintf(stderr, "snd_pcm_hw_params_set_rate_near: %d (%s)\n", err, snd_strerror(err));
        return 1;
    }

    if((err = snd_pcm_hw_params_set_channels(pcm, hw_params, 2)) < 0){
        fprintf(stderr, "snd_pcm_hw_params_set_channels: %d (%s)\n", err, snd_strerror(err));
        return 1;
    }

    bytes = 512;
    if((err = snd_pcm_hw_params_set_buffer_size_near(pcm, hw_params, &bytes)) < 0){
        fprintf(stderr, "snd_pcm_hw_params_set_buffer_size_near: %d (%s)\n", err, snd_strerror(err));
        return 1;
    }
    fprintf(stderr, "bytes: %lu\n", bytes);

    if((err = snd_pcm_hw_params(pcm, hw_params)) < 0){
        fprintf(stderr, "snd_pcm_hw_params: %d (%s)\n", err, snd_strerror(err));
        return 1;
    }

    snd_pcm_hw_params_free(hw_params);
    snd_pcm_close(pcm);

    return 0;
}