diff options
Diffstat (limited to 'gr-audio-alsa/src/audio_alsa_sink.cc')
| -rw-r--r-- | gr-audio-alsa/src/audio_alsa_sink.cc | 22 |
1 files changed, 17 insertions, 5 deletions
diff --git a/gr-audio-alsa/src/audio_alsa_sink.cc b/gr-audio-alsa/src/audio_alsa_sink.cc index d6b7f84cf..d44a93b3f 100644 --- a/gr-audio-alsa/src/audio_alsa_sink.cc +++ b/gr-audio-alsa/src/audio_alsa_sink.cc @@ -90,7 +90,7 @@ audio_alsa_sink::audio_alsa_sink (int sampling_rate, d_period_size (0), d_buffer_size_bytes (0), d_buffer (0), d_worker (0), d_special_case_mono_to_stereo (false), - d_nunderuns (0), d_nsuspends (0) + d_nunderuns (0), d_nsuspends (0), d_ok_to_block(ok_to_block) { CHATTY_DEBUG = gr_prefs::singleton()->get_bool("audio_alsa", "verbose", false); @@ -100,6 +100,8 @@ audio_alsa_sink::audio_alsa_sink (int sampling_rate, // open the device for playback error = snd_pcm_open(&d_pcm_handle, d_device_name.c_str (), SND_PCM_STREAM_PLAYBACK, 0); + if (ok_to_block == false) + snd_pcm_nonblock(d_pcm_handle, !ok_to_block); if (error < 0){ fprintf (stderr, "audio_alsa_sink[%s]: %s\n", d_device_name.c_str(), snd_strerror(error)); @@ -219,9 +221,15 @@ audio_alsa_sink::check_topology (int ninputs, int noutputs) int nchan = ninputs; int err; - // FIXME check_topology may be called more than once. + // Check the state of the stream // Ensure that the pcm is in a state where we can still mess with the hw_params - + snd_pcm_state_t state; + state=snd_pcm_state(d_pcm_handle); + if ( state== SND_PCM_STATE_RUNNING) + return true; // If stream is running, don't change any parameters + else if(state == SND_PCM_STATE_XRUN ) + snd_pcm_prepare ( d_pcm_handle ); // Prepare stream on underrun, and we can set parameters; + bool special_case = nchan == 1 && d_special_case_mono_to_stereo; if (special_case) nchan = 2; @@ -287,7 +295,6 @@ audio_alsa_sink::check_topology (int ninputs, int noutputs) default: assert (0); } - return true; } @@ -489,7 +496,12 @@ audio_alsa_sink::write_buffer (const void *vbuffer, while (nframes > 0){ int r = snd_pcm_writei (d_pcm_handle, buffer, nframes); if (r == -EAGAIN) - continue; // try again + { + if (d_ok_to_block == true) + continue; // try again + + break; + } else if (r == -EPIPE){ // underrun d_nunderuns++; |