Fix busy loop in FakeAudioDeviceModule.

webrtc/modules/audio_device/include/fake_audio_device.h

 /*
  *  Copyright (c) 2013 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 23 matching lines @@
   virtual int32_t SetPlayoutDevice(uint16_t index) { return 0; }
   virtual int32_t SetPlayoutDevice(WindowsDeviceType device) { return 0; }
   virtual int32_t SetStereoPlayout(bool enable) { return 0; }
   virtual int32_t StopPlayout() { return 0; }
   virtual int32_t InitMicrophone() { return 0; }
   virtual int32_t SetRecordingDevice(uint16_t index) { return 0; }
   virtual int32_t SetRecordingDevice(WindowsDeviceType device) { return 0; }
   virtual int32_t SetStereoRecording(bool enable) { return 0; }
   virtual int32_t SetAGC(bool enable) { return 0; }
   virtual int32_t StopRecording() { return 0; }
-  virtual int64_t TimeUntilNextProcess() { return 0; }
-  virtual void Process() {}
+
+  // If the subclass doesn't override the ProcessThread implementation,
+  // we'll fall back on an implementation that doesn't eat too much CPU.
+  virtual int64_t TimeUntilNextProcess() {
+    if (turn_off_module_callbacks_)

[the sun, 2017/02/25 20:01:07]

return time_until_next_process_;

+      return 7 * 24 * 60 * 60 * 1000;  // call me next week.
+    uses_default_module_implementation_ = true;
+    return 10;
+  }
+
+  virtual void Process() {
+    turn_off_module_callbacks_ = uses_default_module_implementation_;

[the sun, 2017/02/25 20:01:07]

// After first call to Process(), we wait a long time to avoid hogging CPU.
time_until_next_process_ = 7 * 24 * 60 * 60 * 1000;  // call me next week.

+  }
+
   virtual int32_t Terminate() { return 0; }
 
   virtual int32_t ActiveAudioLayer(AudioLayer* audioLayer) const { return 0; }
   virtual ErrorCode LastError() const { return kAdmErrNone; }
   virtual bool Initialized() const { return true; }
   virtual int16_t PlayoutDevices() { return 0; }
   virtual int16_t RecordingDevices() { return 0; }
   virtual int32_t PlayoutDeviceName(uint16_t index,
                             char name[kAdmMaxDeviceNameSize],
                             char guid[kAdmMaxGuidSize]) {
@@ skipping 104 matching lines @@
   virtual int32_t EnableBuiltInNS(bool enable) { return -1; }
 
 #if defined(WEBRTC_IOS)
   virtual int GetPlayoutAudioParameters(AudioParameters* params) const {
     return -1;
   }
   virtual int GetRecordAudioParameters(AudioParameters* params) const {
     return -1;
   }
 #endif  // WEBRTC_IOS
+
+ private:
+  bool uses_default_module_implementation_ = false;

[the sun, 2017/02/25 20:01:07]

int64_t time_until_next_process_ = 10;

+  bool turn_off_module_callbacks_ = false;
 };
 
 }  // namespace webrtc
 
 #endif  // WEBRTC_MODULES_AUDIO_DEVICE_INCLUDE_FAKE_AUDIO_DEVICE_H_