Refactor adjust channels buffer provider.

Combine adjust channels buffer provider and adjust channels non-destructive
buffer provider.
When contracting mono + haptic channels to mono, do not use
adjust_channels to avoid mixing haptic channel into audio channel.

Bug: 125915810
Test: play audio-haptic coupled files
Change-Id: I39916a3e0628a44ed4a148c265564af7135a2176
diff --git a/media/libaudioclient/include/media/AudioMixer.h b/media/libaudioclient/include/media/AudioMixer.h
index 41b425f..783eef3 100644
--- a/media/libaudioclient/include/media/AudioMixer.h
+++ b/media/libaudioclient/include/media/AudioMixer.h
@@ -273,7 +273,7 @@
             mPostDownmixReformatBufferProvider.reset(nullptr);
             mDownmixerBufferProvider.reset(nullptr);
             mReformatBufferProvider.reset(nullptr);
-            mAdjustChannelsNonDestructiveBufferProvider.reset(nullptr);
+            mContractChannelsNonDestructiveBufferProvider.reset(nullptr);
             mAdjustChannelsBufferProvider.reset(nullptr);
         }
 
@@ -347,8 +347,12 @@
          * all pre-mixer track buffer conversions outside the AudioMixer class.
          *
          * 1) mInputBufferProvider: The AudioTrack buffer provider.
-         * 2) mAdjustChannelsBufferProvider: Expend or contracts data
-         * 3) mAdjustChannelsNonDestructiveBufferProvider: Non-destructively adjust sample data
+         * 2) mAdjustChannelsBufferProvider: Expands or contracts sample data from one interleaved
+         *    channel format to another. Expanded channels are filled with zeros and put at the end
+         *    of each audio frame. Contracted channels are copied to the end of the buffer.
+         * 3) mContractChannelsNonDestructiveBufferProvider: Non-destructively contract sample data.
+         *    This is currently using at audio-haptic coupled playback to separate audio and haptic
+         *    data. Contracted channels could be written to given buffer.
          * 4) mReformatBufferProvider: If not NULL, performs the audio reformat to
          *    match either mMixerInFormat or mDownmixRequiresFormat, if the downmixer
          *    requires reformat. For example, it may convert floating point input to
@@ -360,9 +364,10 @@
          * 7) mTimestretchBufferProvider: Adds timestretching for playback rate
          */
         AudioBufferProvider*     mInputBufferProvider;    // externally provided buffer provider.
-        // TODO: combine AdjustChannelsBufferProvider and AdjustChannelsNonDestructiveBufferProvider
+        // TODO: combine mAdjustChannelsBufferProvider and
+        // mContractChannelsNonDestructiveBufferProvider
         std::unique_ptr<PassthruBufferProvider> mAdjustChannelsBufferProvider;
-        std::unique_ptr<PassthruBufferProvider> mAdjustChannelsNonDestructiveBufferProvider;
+        std::unique_ptr<PassthruBufferProvider> mContractChannelsNonDestructiveBufferProvider;
         std::unique_ptr<PassthruBufferProvider> mReformatBufferProvider;
         std::unique_ptr<PassthruBufferProvider> mDownmixerBufferProvider;
         std::unique_ptr<PassthruBufferProvider> mPostDownmixReformatBufferProvider;
diff --git a/media/libaudioprocessing/AudioMixer.cpp b/media/libaudioprocessing/AudioMixer.cpp
index 2c57db7..f7cc096 100644
--- a/media/libaudioprocessing/AudioMixer.cpp
+++ b/media/libaudioprocessing/AudioMixer.cpp
@@ -408,8 +408,8 @@
 void AudioMixer::Track::unprepareForAdjustChannelsNonDestructive()
 {
     ALOGV("AUDIOMIXER::unprepareForAdjustChannelsNonDestructive");
-    if (mAdjustChannelsNonDestructiveBufferProvider.get() != nullptr) {
-        mAdjustChannelsNonDestructiveBufferProvider.reset(nullptr);
+    if (mContractChannelsNonDestructiveBufferProvider.get() != nullptr) {
+        mContractChannelsNonDestructiveBufferProvider.reset(nullptr);
         reconfigureBufferProviders();
     }
 }
@@ -426,13 +426,13 @@
                 ? (uint8_t*)mainBuffer + frames * audio_bytes_per_frame(
                         mMixerChannelCount, mMixerFormat)
                 : NULL;
-        mAdjustChannelsNonDestructiveBufferProvider.reset(
-                new AdjustChannelsNonDestructiveBufferProvider(
+        mContractChannelsNonDestructiveBufferProvider.reset(
+                new AdjustChannelsBufferProvider(
                         mFormat,
                         mAdjustNonDestructiveInChannelCount,
                         mAdjustNonDestructiveOutChannelCount,
-                        mKeepContractedChannels ? mMixerFormat : AUDIO_FORMAT_INVALID,
                         frames,
+                        mKeepContractedChannels ? mMixerFormat : AUDIO_FORMAT_INVALID,
                         buffer));
         reconfigureBufferProviders();
     }
@@ -441,9 +441,9 @@
 
 void AudioMixer::Track::clearContractedBuffer()
 {
-    if (mAdjustChannelsNonDestructiveBufferProvider.get() != nullptr) {
-        static_cast<AdjustChannelsNonDestructiveBufferProvider*>(
-                mAdjustChannelsNonDestructiveBufferProvider.get())->clearContractedFrames();
+    if (mContractChannelsNonDestructiveBufferProvider.get() != nullptr) {
+        static_cast<AdjustChannelsBufferProvider*>(
+                mContractChannelsNonDestructiveBufferProvider.get())->clearContractedFrames();
     }
 }
 
@@ -455,9 +455,9 @@
         mAdjustChannelsBufferProvider->setBufferProvider(bufferProvider);
         bufferProvider = mAdjustChannelsBufferProvider.get();
     }
-    if (mAdjustChannelsNonDestructiveBufferProvider.get() != nullptr) {
-        mAdjustChannelsNonDestructiveBufferProvider->setBufferProvider(bufferProvider);
-        bufferProvider = mAdjustChannelsNonDestructiveBufferProvider.get();
+    if (mContractChannelsNonDestructiveBufferProvider.get() != nullptr) {
+        mContractChannelsNonDestructiveBufferProvider->setBufferProvider(bufferProvider);
+        bufferProvider = mContractChannelsNonDestructiveBufferProvider.get();
     }
     if (mReformatBufferProvider.get() != nullptr) {
         mReformatBufferProvider->setBufferProvider(bufferProvider);
@@ -966,8 +966,8 @@
         track->mDownmixerBufferProvider->reset();
     } else if (track->mReformatBufferProvider.get() != nullptr) {
         track->mReformatBufferProvider->reset();
-    } else if (track->mAdjustChannelsNonDestructiveBufferProvider.get() != nullptr) {
-        track->mAdjustChannelsNonDestructiveBufferProvider->reset();
+    } else if (track->mContractChannelsNonDestructiveBufferProvider.get() != nullptr) {
+        track->mContractChannelsNonDestructiveBufferProvider->reset();
     } else if (track->mAdjustChannelsBufferProvider.get() != nullptr) {
         track->mAdjustChannelsBufferProvider->reset();
     }
diff --git a/media/libaudioprocessing/BufferProviders.cpp b/media/libaudioprocessing/BufferProviders.cpp
index b764ccb..21d25e1 100644
--- a/media/libaudioprocessing/BufferProviders.cpp
+++ b/media/libaudioprocessing/BufferProviders.cpp
@@ -627,79 +627,68 @@
     }
 }
 
-AdjustChannelsBufferProvider::AdjustChannelsBufferProvider(audio_format_t format,
-        size_t inChannelCount, size_t outChannelCount, size_t frameCount) :
+AdjustChannelsBufferProvider::AdjustChannelsBufferProvider(
+        audio_format_t format, size_t inChannelCount, size_t outChannelCount,
+        size_t frameCount, audio_format_t contractedFormat, void* contractedBuffer) :
         CopyBufferProvider(
                 audio_bytes_per_frame(inChannelCount, format),
-                audio_bytes_per_frame(outChannelCount, format),
+                audio_bytes_per_frame(std::max(inChannelCount, outChannelCount), format),
                 frameCount),
         mFormat(format),
         mInChannelCount(inChannelCount),
         mOutChannelCount(outChannelCount),
-        mSampleSizeInBytes(audio_bytes_per_sample(format))
-{
-    ALOGV("AdjustBufferProvider(%p)(%#x, %zu, %zu, %zu)",
-            this, format, inChannelCount, outChannelCount, frameCount);
-}
-
-void AdjustChannelsBufferProvider::copyFrames(void *dst, const void *src, size_t frames)
-{
-    adjust_channels(src, mInChannelCount, dst, mOutChannelCount, mSampleSizeInBytes,
-            frames * mInChannelCount * mSampleSizeInBytes);
-}
-
-AdjustChannelsNonDestructiveBufferProvider::AdjustChannelsNonDestructiveBufferProvider(
-        audio_format_t format, size_t inChannelCount, size_t outChannelCount,
-        audio_format_t contractedFormat, size_t contractedFrameCount, void* contractedBuffer) :
-        CopyBufferProvider(
-                audio_bytes_per_frame(std::max(inChannelCount, outChannelCount), format),
-                audio_bytes_per_frame(std::max(inChannelCount, outChannelCount), format),
-                contractedFrameCount),
-        mFormat(format),
-        mInChannelCount(inChannelCount),
-        mOutChannelCount(outChannelCount),
         mSampleSizeInBytes(audio_bytes_per_sample(format)),
+        mFrameCount(frameCount),
         mContractedChannelCount(inChannelCount - outChannelCount),
         mContractedFormat(contractedFormat),
-        mContractedFrameCount(contractedFrameCount),
         mContractedBuffer(contractedBuffer),
         mContractedWrittenFrames(0)
 {
-    ALOGV("AdjustChannelsNonDestructiveBufferProvider(%p)(%#x, %zu, %zu, %#x, %p)",
-            this, format, inChannelCount, outChannelCount, contractedFormat, contractedBuffer);
+    ALOGV("AdjustChannelsBufferProvider(%p)(%#x, %zu, %zu, %zu, %#x, %p)", this, format,
+            inChannelCount, outChannelCount, frameCount, contractedFormat, contractedBuffer);
     if (mContractedFormat != AUDIO_FORMAT_INVALID && mInChannelCount > mOutChannelCount) {
         mContractedFrameSize = audio_bytes_per_frame(mContractedChannelCount, mContractedFormat);
     }
 }
 
-status_t AdjustChannelsNonDestructiveBufferProvider::getNextBuffer(
-        AudioBufferProvider::Buffer* pBuffer)
+status_t AdjustChannelsBufferProvider::getNextBuffer(AudioBufferProvider::Buffer* pBuffer)
 {
-    const size_t outFramesLeft = mContractedFrameCount - mContractedWrittenFrames;
-    if (outFramesLeft < pBuffer->frameCount) {
-        // Restrict the frame count so that we don't write over the size of the output buffer.
-        pBuffer->frameCount = outFramesLeft;
+    if (mContractedBuffer != nullptr) {
+        // Restrict frame count only when it is needed to save contracted frames.
+        const size_t outFramesLeft = mFrameCount - mContractedWrittenFrames;
+        if (outFramesLeft < pBuffer->frameCount) {
+            // Restrict the frame count so that we don't write over the size of the output buffer.
+            pBuffer->frameCount = outFramesLeft;
+        }
     }
     return CopyBufferProvider::getNextBuffer(pBuffer);
 }
 
-void AdjustChannelsNonDestructiveBufferProvider::copyFrames(
-        void *dst, const void *src, size_t frames)
+void AdjustChannelsBufferProvider::copyFrames(void *dst, const void *src, size_t frames)
 {
-    adjust_channels_non_destructive(src, mInChannelCount, dst, mOutChannelCount, mSampleSizeInBytes,
-            frames * mInChannelCount * mSampleSizeInBytes);
-    if (mContractedFormat != AUDIO_FORMAT_INVALID && mContractedBuffer != NULL
-            && mInChannelCount > mOutChannelCount) {
-        const size_t contractedIdx = frames * mOutChannelCount * mSampleSizeInBytes;
-        memcpy_by_audio_format(
-                (uint8_t*)mContractedBuffer + mContractedWrittenFrames * mContractedFrameSize,
-                mContractedFormat, (uint8_t*)dst + contractedIdx, mFormat,
-                mContractedChannelCount * frames);
-        mContractedWrittenFrames += frames;
+    if (mInChannelCount > mOutChannelCount) {
+        // For case multi to mono, adjust_channels has special logic that will mix first two input
+        // channels into a single output channel. In that case, use adjust_channels_non_destructive
+        // to keep only one channel data even when contracting to mono.
+        adjust_channels_non_destructive(src, mInChannelCount, dst, mOutChannelCount,
+                mSampleSizeInBytes, frames * mInChannelCount * mSampleSizeInBytes);
+        if (mContractedFormat != AUDIO_FORMAT_INVALID
+            && mContractedBuffer != nullptr) {
+            const size_t contractedIdx = frames * mOutChannelCount * mSampleSizeInBytes;
+            memcpy_by_audio_format(
+                    (uint8_t*) mContractedBuffer + mContractedWrittenFrames * mContractedFrameSize,
+                    mContractedFormat, (uint8_t*) dst + contractedIdx, mFormat,
+                    mContractedChannelCount * frames);
+            mContractedWrittenFrames += frames;
+        }
+    } else {
+        // Prefer expanding data from the end of each audio frame.
+        adjust_channels(src, mInChannelCount, dst, mOutChannelCount,
+                mSampleSizeInBytes, frames * mInChannelCount * mSampleSizeInBytes);
     }
 }
 
-void AdjustChannelsNonDestructiveBufferProvider::reset()
+void AdjustChannelsBufferProvider::reset()
 {
     mContractedWrittenFrames = 0;
     CopyBufferProvider::reset();
diff --git a/media/libmedia/include/media/BufferProviders.h b/media/libmedia/include/media/BufferProviders.h
index ea41527..b038854 100644
--- a/media/libmedia/include/media/BufferProviders.h
+++ b/media/libmedia/include/media/BufferProviders.h
@@ -218,33 +218,21 @@
     bool                 mAudioPlaybackRateValid; // flag for current parameters validity
 };
 
-// AdjustBufferProvider derives from CopyBufferProvider to adjust sample data.
+// AdjustChannelsBufferProvider derives from CopyBufferProvider to adjust sample data.
 // Expands or contracts sample data from one interleaved channel format to another.
-// Expanded channels are filled with zeros and put at the end of each audio frame.
-// Contracted channels are omitted from the end of each audio frame.
+// Extra expanded channels are filled with zeros and put at the end of each audio frame.
+// Contracted channels are copied to the end of the output buffer(storage should be
+// allocated appropriately).
+// Contracted channels could be written to output buffer.
 class AdjustChannelsBufferProvider : public CopyBufferProvider {
 public:
     AdjustChannelsBufferProvider(audio_format_t format, size_t inChannelCount,
-            size_t outChannelCount, size_t frameCount);
-    //Overrides
-    void copyFrames(void *dst, const void *src, size_t frames) override;
-
-protected:
-    const audio_format_t mFormat;
-    const size_t         mInChannelCount;
-    const size_t         mOutChannelCount;
-    const size_t         mSampleSizeInBytes;
-};
-
-// AdjustChannelsNonDestructiveBufferProvider derives from CopyBufferProvider to adjust sample data.
-// Expands or contracts sample data from one interleaved channel format to another.
-// Extra expanded channels are interleaved in from the end of the input buffer.
-// Contracted channels are copied to the end of the output buffer.
-// Contracted channels could be written to output buffer.
-class AdjustChannelsNonDestructiveBufferProvider : public CopyBufferProvider {
-public:
-    AdjustChannelsNonDestructiveBufferProvider(audio_format_t format, size_t inChannelCount,
-            size_t outChannelCount, audio_format_t contractedFormat, size_t contractedFrameCount,
+            size_t outChannelCount, size_t frameCount) : AdjustChannelsBufferProvider(
+                    format, inChannelCount, outChannelCount,
+                    frameCount, AUDIO_FORMAT_INVALID, nullptr) { }
+    // Contracted data is converted to contractedFormat and put into contractedBuffer.
+    AdjustChannelsBufferProvider(audio_format_t format, size_t inChannelCount,
+            size_t outChannelCount, size_t frameCount, audio_format_t contractedFormat,
             void* contractedBuffer);
     //Overrides
     status_t getNextBuffer(Buffer* pBuffer) override;
@@ -258,9 +246,9 @@
     const size_t         mInChannelCount;
     const size_t         mOutChannelCount;
     const size_t         mSampleSizeInBytes;
+    const size_t         mFrameCount;
     const size_t         mContractedChannelCount;
     const audio_format_t mContractedFormat;
-    const size_t         mContractedFrameCount;
     void                *mContractedBuffer;
     size_t               mContractedWrittenFrames;
     size_t               mContractedFrameSize;