V4L2Decoder: Clear mFrameAtDevice when streamoff the output queue

|mFrameAtDevice| is to track the buffers enqueued in the V4L2 output
queue. When we streamoff the V4L2 queue, all of the enqueued buffers
are dropped immediately. Therefore we should also clear
|mFrameAtDevice| at the same time.

Bug: 166072201
Test: Run gts.DashTest#testWidevineVp9AdaptiveWithRendererDisabling
      and check the error message added by this CL doesn't appear.
Change-Id: Ibda5949710e66e78a6f49c80c57e94c93fe69afc

1 files changed, 7 insertions, 0 deletions

diff --git a/components/V4L2Decoder.cpp b/components/V4L2Decoder.cpp
index f066fd4..a5ef3fb 100644
--- a/components/V4L2Decoder.cpp
+++ b/components/V4L2Decoder.cpp
@@ -317,6 +317,7 @@ void V4L2Decoder::flush() {
     // Streamoff V4L2 queues to drop input and output buffers.
     mDevice->StopPolling();
     mOutputQueue->Streamoff();
+    mFrameAtDevice.clear();
     mInputQueue->Streamoff();
 
     // Streamon input queue again.
@@ -471,6 +472,7 @@ bool V4L2Decoder::changeResolution() {
 
     mOutputQueue->Streamoff();
     mOutputQueue->DeallocateBuffers();
+    mFrameAtDevice.clear();
     mBlockIdToV4L2Id.clear();
 
     if (mOutputQueue->AllocateBuffers(*numOutputBuffers, V4L2_MEMORY_DMABUF) == 0) {
@@ -557,6 +559,11 @@ void V4L2Decoder::onVideoFrameReady(
     ALOGV("QBUF to output queue, blockId=%u, V4L2Id=%u", blockId, v4l2Id);
 
     std::move(*outputBuffer).QueueDMABuf(frame->getFDs());
+    if (mFrameAtDevice.find(v4l2Id) != mFrameAtDevice.end()) {
+        ALOGE("%s(): V4L2 buffer %d already enqueued.", __func__, v4l2Id);
+        onError();
+        return;
+    }
     mFrameAtDevice.insert(std::make_pair(v4l2Id, std::move(frame)));
 
     tryFetchVideoFrame();