From 2516e94eb9f7ff5670d0f6ed129a131408d2e4b0 Mon Sep 17 00:00:00 2001
From: andrewlewis <andrewlewis@google.com>
Date: Thu, 3 Dec 2020 09:56:22 +0000
Subject: [PATCH] Fix `SonicAudioProcessor` end of stream behavior

The `AudioProcessor` interface requires that no more input is queued after
queueing end of stream, but `DefaultAudioSink` did queue more input and the
implementation of `SonicAudioProcessor` actually relied on this to drain output
at the end of the stream.

Fix this behavior by getting `Sonic` output in `getOutput` and having
`DefaultAudioSink` only queue input to processors that are not draining.

Also add TODOs to clean up audio processor implementations where the code
handles interaction that doesn't conform to the interface.

PiperOrigin-RevId: 345406478
---
 .../exoplayer2/ext/gvr/GvrAudioProcessor.java |  1 +
 .../exoplayer2/audio/DefaultAudioSink.java    |  4 +-
 .../exoplayer2/audio/SonicAudioProcessor.java | 47 ++++++++++---------
 3 files changed, 30 insertions(+), 22 deletions(-)

diff --git a/extensions/gvr/src/main/java/com/google/android/exoplayer2/ext/gvr/GvrAudioProcessor.java b/extensions/gvr/src/main/java/com/google/android/exoplayer2/ext/gvr/GvrAudioProcessor.java
index 14570759c3..041ca09db4 100644
--- a/extensions/gvr/src/main/java/com/google/android/exoplayer2/ext/gvr/GvrAudioProcessor.java
+++ b/extensions/gvr/src/main/java/com/google/android/exoplayer2/ext/gvr/GvrAudioProcessor.java
@@ -135,6 +135,7 @@ public class GvrAudioProcessor implements AudioProcessor {
 
   @Override
   public void queueEndOfStream() {
+    // TODO(internal b/174554082): assert gvrAudioSurround is non-null here and in getOutput.
     if (gvrAudioSurround != null) {
       gvrAudioSurround.triggerProcessing();
     }
diff --git a/library/core/src/main/java/com/google/android/exoplayer2/audio/DefaultAudioSink.java b/library/core/src/main/java/com/google/android/exoplayer2/audio/DefaultAudioSink.java
index 26ec4b94c2..691580143a 100644
--- a/library/core/src/main/java/com/google/android/exoplayer2/audio/DefaultAudioSink.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/audio/DefaultAudioSink.java
@@ -869,7 +869,9 @@ public final class DefaultAudioSink implements AudioSink {
         writeBuffer(input, avSyncPresentationTimeUs);
       } else {
         AudioProcessor audioProcessor = activeAudioProcessors[index];
-        audioProcessor.queueInput(input);
+        if (index > drainingAudioProcessorIndex) {
+          audioProcessor.queueInput(input);
+        }
         ByteBuffer output = audioProcessor.getOutput();
         outputBuffers[index] = output;
         if (output.hasRemaining()) {
diff --git a/library/core/src/main/java/com/google/android/exoplayer2/audio/SonicAudioProcessor.java b/library/core/src/main/java/com/google/android/exoplayer2/audio/SonicAudioProcessor.java
index ef5bbbc078..f859761954 100644
--- a/library/core/src/main/java/com/google/android/exoplayer2/audio/SonicAudioProcessor.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/audio/SonicAudioProcessor.java
@@ -165,32 +165,20 @@ public final class SonicAudioProcessor implements AudioProcessor {
 
   @Override
   public void queueInput(ByteBuffer inputBuffer) {
+    if (!inputBuffer.hasRemaining()) {
+      return;
+    }
     Sonic sonic = checkNotNull(this.sonic);
-    if (inputBuffer.hasRemaining()) {
-      ShortBuffer shortBuffer = inputBuffer.asShortBuffer();
-      int inputSize = inputBuffer.remaining();
-      inputBytes += inputSize;
-      sonic.queueInput(shortBuffer);
-      inputBuffer.position(inputBuffer.position() + inputSize);
-    }
-    int outputSize = sonic.getOutputSize();
-    if (outputSize > 0) {
-      if (buffer.capacity() < outputSize) {
-        buffer = ByteBuffer.allocateDirect(outputSize).order(ByteOrder.nativeOrder());
-        shortBuffer = buffer.asShortBuffer();
-      } else {
-        buffer.clear();
-        shortBuffer.clear();
-      }
-      sonic.getOutput(shortBuffer);
-      outputBytes += outputSize;
-      buffer.limit(outputSize);
-      outputBuffer = buffer;
-    }
+    ShortBuffer shortBuffer = inputBuffer.asShortBuffer();
+    int inputSize = inputBuffer.remaining();
+    inputBytes += inputSize;
+    sonic.queueInput(shortBuffer);
+    inputBuffer.position(inputBuffer.position() + inputSize);
   }
 
   @Override
   public void queueEndOfStream() {
+    // TODO(internal b/174554082): assert sonic is non-null here and in getOutput.
     if (sonic != null) {
       sonic.queueEndOfStream();
     }
@@ -199,6 +187,23 @@ public final class SonicAudioProcessor implements AudioProcessor {
 
   @Override
   public ByteBuffer getOutput() {
+    @Nullable Sonic sonic = this.sonic;
+    if (sonic != null) {
+      int outputSize = sonic.getOutputSize();
+      if (outputSize > 0) {
+        if (buffer.capacity() < outputSize) {
+          buffer = ByteBuffer.allocateDirect(outputSize).order(ByteOrder.nativeOrder());
+          shortBuffer = buffer.asShortBuffer();
+        } else {
+          buffer.clear();
+          shortBuffer.clear();
+        }
+        sonic.getOutput(shortBuffer);
+        outputBytes += outputSize;
+        buffer.limit(outputSize);
+        outputBuffer = buffer;
+      }
+    }
     ByteBuffer outputBuffer = this.outputBuffer;
     this.outputBuffer = EMPTY_BUFFER;
     return outputBuffer;