/* Callback called by JACK when audio is available
Use as little CPU time as possible, just copy accross the audio
into the ring buffer
*/
static int process_callback(jack_nframes_t nframes, void *arg)
{
MastSendTool* tool = (MastSendTool*)arg;
unsigned int channels = tool->get_input_channels();
size_t to_write = 0, written = 0;
unsigned int c,n;
// Process channel by channel
for (c=0; c < channels; c++)
{
jack_default_audio_sample_t *buf = (jack_default_audio_sample_t*)
jack_port_get_buffer(g_jackport[c], nframes);
// Interleave the left and right channels
for(n=0; n<nframes; n++) {
g_interleavebuf[(n*channels)+c] = buf[n];
}
}
// Now write the interleaved audio to the ring buffer
to_write = sizeof(float) * nframes * channels;
written = jack_ringbuffer_write(g_ringbuffer, (char*)g_interleavebuf, to_write);
if (to_write > written) {
// If this goes wrong, then the buffer goes out of sync and we get static
MAST_FATAL("Failed to write to ring ruffer, try increading the ring-buffer size");
return 1;
}
// Signal the other thread that audio is available
pthread_cond_signal(&g_ringbuffer_cond);
// Success
return 0;
}
// Callback called by JACK when buffersize changes
static int buffersize_callback(jack_nframes_t nframes, void *arg)
{
MastSendTool* tool = (MastSendTool*)arg;
int channels = tool->get_input_channels();
MAST_DEBUG("JACK buffer size is %d samples long", nframes);
// (re-)allocate conversion buffer
g_interleavebuf = (jack_default_audio_sample_t*)
realloc( g_interleavebuf, nframes * sizeof(float) * channels );
if (g_interleavebuf == NULL) {
MAST_FATAL("Failed to (re-)allocate the convertion buffer");
}
// Success
return 0;
}