Bug 10897368: webrtc & PulseAudio: don't crash in case of buffer holes r=jesup

media/webrtc/trunk/webrtc/modules/audio_device/linux/audio_device_pulse_linux.cc

@@ -2473,6 +2473,18 @@ void AudioDeviceLinuxPulse::PaStreamReadCallbackHandler()
         return;
     }
 
+    // PulseAudio record streams can have holes (for reasons not entirely clear
+    // to the PA developers themselves). Since version 4 of PA, these are passed
+    // over to the application (us), signaled by a non-zero sample data size
+    // (the size of the hole) and a NULL sample data.
+    // We handle stream holes as recommended by PulseAudio, i.e. by skipping
+    // it, which is done with a stream drop.
+    if (_tempSampleDataSize && !_tempSampleData) {
+        LATE(pa_stream_drop)(_recStream);
+        _tempSampleDataSize = 0; // reset
+        return;
+    }
+
     // Since we consume the data asynchronously on a different thread, we have
     // to temporarily disable the read callback or else Pulse will call it
     // continuously until we consume the data. We re-enable it below