V4L2Decoder: pass the same output buffer to V4L2 Queue slot

Originally we pass arbitrary output buffers to V4L2 Queue. However,
the V4L2 stateful API requires the caller pass the same buffers to the
output queue slot. This CL implement this requirement.

Bug: 161770200
Bug: 161323057
Test: arc.VideoDecodeAccel.h264_vm runs first test successfully.
Change-Id: I8f6c8871997f310425571b3983ae86f05c0c37c6

1 files changed, 23 insertions, 15 deletions

diff --git a/components/V4L2Decoder.cpp b/components/V4L2Decoder.cpp
index 275357e..71e3dc4 100644
--- a/components/V4L2Decoder.cpp
+++ b/components/V4L2Decoder.cpp
@@ -9,6 +9,8 @@
 
 #include <stdint.h>
 
+#include <vector>
+
 #include <base/bind.h>
 #include <base/memory/ptr_util.h>
 #include <log/log.h>
@@ -501,30 +503,36 @@ void V4L2Decoder::tryFetchVideoFrame() {
         return;
     }
 
-    auto outputBuffer = mOutputQueue->GetFreeBuffer();
-    if (!outputBuffer) {
-        ALOGD("No free output buffer.");
-        return;
-    }
-    mVideoFramePool->getVideoFrame(
-            ::base::BindOnce(&V4L2Decoder::onVideoFrameReady, mWeakThis, std::move(*outputBuffer)));
+    mVideoFramePool->getVideoFrame(::base::BindOnce(&V4L2Decoder::onVideoFrameReady, mWeakThis));
 }
 
-void V4L2Decoder::onVideoFrameReady(media::V4L2WritableBufferRef outputBuffer,
-                                    std::unique_ptr<VideoFrame> frame) {
+void V4L2Decoder::onVideoFrameReady(
+        std::optional<VideoFramePool::FrameWithBlockId> frameWithBlockId) {
     ALOGV("%s()", __func__);
     ALOG_ASSERT(mTaskRunner->RunsTasksInCurrentSequence());
 
-    if (!frame) {
-        ALOGE("Get nullptr VideoFrame.");
+    if (!frameWithBlockId) {
+        ALOGE("Got nullptr VideoFrame.");
+        onError();
+        return;
+    }
+
+    // Unwrap our arguments.
+    std::unique_ptr<VideoFrame> frame;
+    uint32_t blockId;
+    std::tie(frame, blockId) = std::move(*frameWithBlockId);
+
+    ::base::Optional<media::V4L2WritableBufferRef> outputBuffer =
+            mOutputQueue->GetFreeBuffer(blockId);
+    if (!outputBuffer) {
+        ALOGE("No free output buffer.");
         onError();
         return;
     }
 
-    size_t bufferId = outputBuffer.BufferId();
-    ALOGV("QBUF to output queue, bufferId=%zu", bufferId);
-    std::move(outputBuffer).QueueDMABuf(frame->getFDs());
-    mFrameAtDevice.insert(std::make_pair(bufferId, std::move(frame)));
+    ALOGV("QBUF to output queue, blockId=%u, fd: %d", blockId, frame->getFDs()[0].get());
+    std::move(*outputBuffer).QueueDMABuf(frame->getFDs());
+    mFrameAtDevice.insert(std::make_pair(blockId, std::move(frame)));
 
     tryFetchVideoFrame();
 }