Avoids error message about unknown selected data source for Port iPhone Microphone

webrtc/modules/audio_device/ios/audio_device_ios.mm

 /*
  *  Copyright (c) 2012 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 10 matching lines @@
 #include "webrtc/base/checks.h"
 #include "webrtc/base/logging.h"
 #include "webrtc/system_wrappers/interface/trace.h"
 
 namespace webrtc {
 
 #define LOGI() LOG(LS_INFO) << "AudioDeviceIOS::"
 
 using ios::CheckAndLogError;
 
-#if !defined(NDEBUG)
-static void LogDeviceInfo() {
-  LOG(LS_INFO) << "LogDeviceInfo";
-  @autoreleasepool {
-    LOG(LS_INFO) << " system name: " << ios::GetSystemName();
-    LOG(LS_INFO) << " system version: " << ios::GetSystemVersion();
-    LOG(LS_INFO) << " device type: " << ios::GetDeviceType();
-    LOG(LS_INFO) << " device name: " << ios::GetDeviceName();
-  }
-}
-#endif
-
 static void ActivateAudioSession(AVAudioSession* session, bool activate) {
   LOG(LS_INFO) << "ActivateAudioSession(" << activate << ")";
   @autoreleasepool {
     NSError* error = nil;
     BOOL success = NO;
     if (!activate) {
       // Deactivate the audio session.
       success = [session setActive:NO error:&error];
       DCHECK(CheckAndLogError(success, error));
       return;
@@ skipping 61 matching lines @@
     // Don't keep the audio session active. Instead, deactivate when needed.
     ActivateAudioSession(session, false);
     // TODO(henrika): to be extra safe, we can do more here. E.g., set
     // preferred values for sample rate, channels etc., re-activate an audio
     // session and verify the actual values again. Then we know for sure that
     // the current values will in fact be correct. Or, we can skip all this
     // and check setting when audio is started. Probably better.
   }
 }
 
+#if !defined(NDEBUG)
+static void LogDeviceInfo() {
+  LOG(LS_INFO) << "LogDeviceInfo";
+  @autoreleasepool {
+    LOG(LS_INFO) << " system name: " << ios::GetSystemName();
+    LOG(LS_INFO) << " system version: " << ios::GetSystemVersion();
+    LOG(LS_INFO) << " device type: " << ios::GetDeviceType();
+    LOG(LS_INFO) << " device name: " << ios::GetDeviceName();
+  }
+}
+#endif
+
 AudioDeviceIOS::AudioDeviceIOS()
     : audio_device_buffer_(nullptr),
       _critSect(*CriticalSectionWrapper::CreateCriticalSection()),
       _auVoiceProcessing(nullptr),
       _audioInterruptionObserver(nullptr),
       _initialized(false),
       _isShutDown(false),
       _recording(false),
       _playing(false),
       _recIsInitialized(false),
@@ skipping 108 matching lines @@
     if (InitPlayOrRecord() == -1) {
       LOG_F(LS_ERROR) << "InitPlayOrRecord failed!";
       return -1;
     }
   }
   _playIsInitialized = true;
   return 0;
 }
 
 int32_t AudioDeviceIOS::InitRecording() {
-  LOGI() << "InitPlayout";
+  LOGI() << "InitRecording";
   DCHECK(thread_checker_.CalledOnValidThread());
   DCHECK(_initialized);
   DCHECK(!_recIsInitialized);
   DCHECK(!_recording);
   if (!_playIsInitialized) {
     if (InitPlayOrRecord() == -1) {
       LOG_F(LS_ERROR) << "InitPlayOrRecord failed!";
       return -1;
     }
   }
@@ skipping 396 matching lines @@
                     AudioOutputUnitStart(_auVoiceProcessing);
                     break;
                   }
                 }
               }];
   // Increment refcount on observer using ARC bridge. Instance variable is a
   // void* instead of an id because header is included in other pure C++
   // files.
   _audioInterruptionObserver = (__bridge_retained void*)observer;
 
-  // Deactivate the audio session.
-  ActivateAudioSession(session, false);
-
   return 0;
 }
 
 int32_t AudioDeviceIOS::ShutdownPlayOrRecord() {
   LOGI() << "ShutdownPlayOrRecord";
 
   if (_audioInterruptionObserver != nullptr) {
     NSNotificationCenter* center = [NSNotificationCenter defaultCenter];
     // Transfer ownership of observer back to ARC, which will dealloc the
     // observer once it exits this scope.
     id observer = (__bridge_transfer id)_audioInterruptionObserver;
     [center removeObserver:observer];
     _audioInterruptionObserver = nullptr;
   }
 
   // Close and delete AU.
   OSStatus result = -1;
   if (nullptr != _auVoiceProcessing) {
     result = AudioOutputUnitStop(_auVoiceProcessing);
     if (0 != result) {
       LOG_F(LS_ERROR) << "AudioOutputUnitStop failed: " << result;
     }
     result = AudioComponentInstanceDispose(_auVoiceProcessing);
     if (0 != result) {
       LOG_F(LS_ERROR) << "AudioComponentInstanceDispose failed: " << result;
     }
     _auVoiceProcessing = nullptr;
   }
 
+  // All I/O should be stopped or paused prior to deactivating the audio
+  // session, hence we deactivate as last action.
+  AVAudioSession* session = [AVAudioSession sharedInstance];
+  ActivateAudioSession(session, false);
   return 0;
 }
 
 // ============================================================================
 //                                  Thread Methods
 // ============================================================================
 
 OSStatus AudioDeviceIOS::RecordProcess(
     void* inRefCon,
     AudioUnitRenderActionFlags* ioActionFlags,
@@ skipping 333 matching lines @@
     //       Device Buffer?
     timespec t;
     t.tv_sec = 0;
     t.tv_nsec = 5 * 1000 * 1000;
     nanosleep(&t, nullptr);
   }
   return true;
 }
 
 }  // namespace webrtc