Enable write side of MonoPipe to be shutdown
Bug: 7253033
Change-Id: Iea8390763b59ffa7a8e2a6b77dd04ea23442698f
diff --git a/include/media/nbaio/MonoPipe.h b/include/media/nbaio/MonoPipe.h
index c47bf6c..5fcfe9e 100644
--- a/include/media/nbaio/MonoPipe.h
+++ b/include/media/nbaio/MonoPipe.h
@@ -77,6 +77,17 @@
void setAvgFrames(size_t setpoint);
size_t maxFrames() const { return mMaxFrames; }
+ // Set the shutdown state for the write side of a pipe.
+ // This may be called by an unrelated thread. When shutdown state is 'true',
+ // a write that would otherwise block instead returns a short transfer count.
+ // There is no guarantee how long it will take for the shutdown to be recognized,
+ // but it will not be an unbounded amount of time.
+ // The state can be restored to normal by calling shutdown(false).
+ void shutdown(bool newState = true);
+
+ // Return true if the write side of a pipe is currently shutdown.
+ bool isShutdown();
+
private:
// A pair of methods and a helper variable which allows the reader and the
// writer to update and observe the values of mFront and mNextRdPTS in an
@@ -114,6 +125,8 @@
int64_t offsetTimestampByAudioFrames(int64_t ts, size_t audFrames);
LinearTransform mSamplesToLocalTime;
+
+ bool mIsShutdown; // whether shutdown(true) was called, no barriers are needed
};
} // namespace android
diff --git a/media/libnbaio/MonoPipe.cpp b/media/libnbaio/MonoPipe.cpp
index bbdc8c1..e8d3d9b 100644
--- a/media/libnbaio/MonoPipe.cpp
+++ b/media/libnbaio/MonoPipe.cpp
@@ -41,7 +41,8 @@
mWriteTsValid(false),
// mWriteTs
mSetpoint((reqFrames * 11) / 16),
- mWriteCanBlock(writeCanBlock)
+ mWriteCanBlock(writeCanBlock),
+ mIsShutdown(false)
{
CCHelper tmpHelper;
status_t res;
@@ -121,7 +122,7 @@
android_atomic_release_store(written + mRear, &mRear);
totalFramesWritten += written;
}
- if (!mWriteCanBlock) {
+ if (!mWriteCanBlock || mIsShutdown) {
break;
}
count -= written;
@@ -299,4 +300,14 @@
return ts + frame_lt_duration;
}
+void MonoPipe::shutdown(bool newState)
+{
+ mIsShutdown = newState;
+}
+
+bool MonoPipe::isShutdown()
+{
+ return mIsShutdown;
+}
+
} // namespace android