Issue 2071329: audio track is shorter than video track for video capture on sholes

Add API to retrieve number of frames dropped by audio input kernel driver.

Submitted on behalf of Masaki Sato <masaki.sato@motorola.com>
diff --git a/include/media/AudioRecord.h b/include/media/AudioRecord.h
index 622c596..92bc126 100644
--- a/include/media/AudioRecord.h
+++ b/include/media/AudioRecord.h
@@ -294,6 +294,13 @@
      */
             ssize_t     read(void* buffer, size_t size);
 
+    /* Return the amount of input frames lost in the audio driver since the last call of this function.
+     * Audio driver is expected to reset the value to 0 and restart counting upon returning the current value by this function call.
+     * Such loss typically occurs when the user space process is blocked longer than the capacity of audio driver buffers.
+     * Unit: the number of input audio frames
+     */
+            unsigned int  getInputFramesLost();
+
 private:
     /* copying audio tracks is not allowed */
                         AudioRecord(const AudioRecord& other);
@@ -348,6 +355,7 @@
     uint32_t                mUpdatePeriod;
     uint32_t                mFlags;
     uint32_t                mChannels;
+    audio_io_handle_t       mInput;
 };
 
 }; // namespace android
diff --git a/include/media/AudioSystem.h b/include/media/AudioSystem.h
index 42bb4df..d0ccc50 100644
--- a/include/media/AudioSystem.h
+++ b/include/media/AudioSystem.h
@@ -233,6 +233,7 @@
     // necessary to check returned status before using the returned values.
     static status_t getRenderPosition(uint32_t *halFrames, uint32_t *dspFrames, int stream = DEFAULT);
 
+    static unsigned int  getInputFramesLost(audio_io_handle_t ioHandle);
     //
     // AudioPolicyService interface
     //
diff --git a/include/media/IAudioFlinger.h b/include/media/IAudioFlinger.h
index bddd23e..c147632 100644
--- a/include/media/IAudioFlinger.h
+++ b/include/media/IAudioFlinger.h
@@ -130,7 +130,10 @@
     virtual status_t setStreamOutput(uint32_t stream, int output) = 0;
 
     virtual status_t setVoiceVolume(float volume) = 0;
+
     virtual status_t getRenderPosition(uint32_t *halFrames, uint32_t *dspFrames, int output) = 0;
+
+    virtual unsigned int  getInputFramesLost(int ioHandle) = 0;
 };
 
 
diff --git a/media/libmedia/AudioRecord.cpp b/media/libmedia/AudioRecord.cpp
index 7bbd0b2..bce3371 100644
--- a/media/libmedia/AudioRecord.cpp
+++ b/media/libmedia/AudioRecord.cpp
@@ -199,6 +199,7 @@
     mUpdatePeriod = 0;
     mInputSource = (uint8_t)inputSource;
     mFlags = flags;
+    mInput = input;
 
     return NO_ERROR;
 }
@@ -384,6 +385,13 @@
     return NO_ERROR;
 }
 
+unsigned int AudioRecord::getInputFramesLost()
+{
+    if (mActive)
+        return AudioSystem::getInputFramesLost(mInput);
+    else
+        return 0;
+}
 
 // -------------------------------------------------------------------------
 
@@ -517,10 +525,11 @@
 
 audio_io_handle_t AudioRecord::getInput()
 {
-   return AudioSystem::getInput(mInputSource,
+    mInput = AudioSystem::getInput(mInputSource,
                                 mCblk->sampleRate,
                                 mFormat, mChannels,
                                 (AudioSystem::audio_in_acoustics)mFlags);
+    return mInput;
 }
 
 // -------------------------------------------------------------------------
diff --git a/media/libmedia/AudioSystem.cpp b/media/libmedia/AudioSystem.cpp
index 3f9c6d6..4b364f2 100644
--- a/media/libmedia/AudioSystem.cpp
+++ b/media/libmedia/AudioSystem.cpp
@@ -354,6 +354,16 @@
     return af->getRenderPosition(halFrames, dspFrames, getOutput((stream_type)stream));
 }
 
+unsigned int AudioSystem::getInputFramesLost(audio_io_handle_t ioHandle) {
+    const sp<IAudioFlinger>& af = AudioSystem::get_audio_flinger();
+    unsigned int result = 0;
+    if (af == 0) return result;
+    if (ioHandle == NULL) return result;
+
+    result = af->getInputFramesLost(ioHandle);
+    return result;
+}
+
 // ---------------------------------------------------------------------------
 
 void AudioSystem::AudioFlingerClient::binderDied(const wp<IBinder>& who) {
diff --git a/media/libmedia/IAudioFlinger.cpp b/media/libmedia/IAudioFlinger.cpp
index ca3a2a6..47bcc12 100644
--- a/media/libmedia/IAudioFlinger.cpp
+++ b/media/libmedia/IAudioFlinger.cpp
@@ -61,7 +61,8 @@
     CLOSE_INPUT,
     SET_STREAM_OUTPUT,
     SET_VOICE_VOLUME,
-    GET_RENDER_POSITION
+    GET_RENDER_POSITION,
+    GET_INPUT_FRAMES_LOST
 };
 
 class BpAudioFlinger : public BpInterface<IAudioFlinger>
@@ -487,6 +488,15 @@
         }
         return status;
     }
+
+    virtual unsigned int getInputFramesLost(int ioHandle)
+    {
+        Parcel data, reply;
+        data.writeInterfaceToken(IAudioFlinger::getInterfaceDescriptor());
+        data.writeInt32(ioHandle);
+        remote()->transact(GET_INPUT_FRAMES_LOST, data, &reply);
+        return reply.readInt32();
+    }
 };
 
 IMPLEMENT_META_INTERFACE(AudioFlinger, "android.media.IAudioFlinger");
@@ -752,6 +762,13 @@
             }
             return NO_ERROR;
         }
+        case GET_INPUT_FRAMES_LOST: {
+            CHECK_INTERFACE(IAudioFlinger, data, reply);
+            int ioHandle = data.readInt32();
+            reply->writeInt32(getInputFramesLost(ioHandle));
+            return NO_ERROR;
+        } break;
+
         default:
             return BBinder::onTransact(code, data, reply, flags);
     }