diff --git a/alsa_fifo.c b/alsa_fifo.c new file mode 100644 index 0000000..3ef04d0 --- /dev/null +++ b/alsa_fifo.c @@ -0,0 +1,86 @@ +#include +#include +#include + +void +read_alsa_fifo (char* pcm_name) +{ + int i; + int err; + short buf[128]; + snd_pcm_t *capture_handle; + snd_pcm_hw_params_t *hw_params; + + if ((err = snd_pcm_open (&capture_handle, pcm_name, SND_PCM_STREAM_CAPTURE, 0)) < 0) { + fprintf (stderr, "cannot open audio device %s (%s)\n", + argv[1], + snd_strerror (err)); + exit (1); + } + + if ((err = snd_pcm_hw_params_malloc (&hw_params)) < 0) { + fprintf (stderr, "cannot allocate hardware parameter structure (%s)\n", + snd_strerror (err)); + exit (1); + } + + if ((err = snd_pcm_hw_params_any (capture_handle, hw_params)) < 0) { + fprintf (stderr, "cannot initialize hardware parameter structure (%s)\n", + snd_strerror (err)); + exit (1); + } + + if ((err = snd_pcm_hw_params_set_access (capture_handle, hw_params, SND_PCM_ACCESS_RW_INTERLEAVED)) < 0) { + fprintf (stderr, "cannot set access type (%s)\n", + snd_strerror (err)); + exit (1); + } + + if ((err = snd_pcm_hw_params_set_format (capture_handle, hw_params, SND_PCM_FORMAT_S16_LE)) < 0) { + fprintf (stderr, "cannot set sample format (%s)\n", + snd_strerror (err)); + exit (1); + } + unsigned int *rate = malloc(sizeof(unsigned int));; + int *dir = malloc (sizeof (int)); + *rate = 44100; + if ((err = snd_pcm_hw_params_set_rate_near (capture_handle, hw_params, rate, dir)) < 0) { + fprintf (stderr, "cannot set sample rate (%s)\n", + snd_strerror (err)); + exit (1); + } + + if ((err = snd_pcm_hw_params_set_channels (capture_handle, hw_params, 2)) < 0) { + fprintf (stderr, "cannot set channel count (%s)\n", + snd_strerror (err)); + exit (1); + } + + if ((err = snd_pcm_hw_params (capture_handle, hw_params)) < 0) { + fprintf (stderr, "cannot set parameters (%s)\n", + snd_strerror (err)); + exit (1); + } + + snd_pcm_hw_params_free (hw_params); + + if ((err = snd_pcm_prepare (capture_handle)) < 0) { + fprintf (stderr, "cannot prepare audio interface for use (%s)\n", + snd_strerror (err)); + exit (1); + } + + while (1) { + if ((err = snd_pcm_readi (capture_handle, buf, 128)) != 128) { + fprintf (stderr, "read from audio interface failed (%s)\n", + snd_strerror (err)); + exit (1); + } + fprintf (stdout, "%s\n", buf); + } + + snd_pcm_close (capture_handle); + free (rate); + free (dir); + exit (0); +}