components: pass weak_ptr to Component::Listener

After the component is destroyed, we cannot use shared_from_this()
because there must be a valid shared_ptr pointing to the component.

This CL changes to use weak_from_this() to get weak_ptr, and locks the
weak_ptr when we need shared_ptr. Also, the parameter of
Component::Listener's methods is weak_ptr, instead of shared_ptr.
This CL also changes to pass weak_ptr to the listener.

Bug: 198215986
Test: android.media.cts.VideoEncoderTest#testOtherH264SurfArbitraryH
Change-Id: I3bae943f211db5f68e3b9a86bc193eee09cba65e

3 files changed, 16 insertions, 31 deletions

diff --git a/components/V4L2DecodeComponent.cpp b/components/V4L2DecodeComponent.cpp
index 2807c88..456f3c4 100644
--- a/components/V4L2DecodeComponent.cpp
+++ b/components/V4L2DecodeComponent.cpp
@@ -202,7 +202,6 @@ c2_status_t V4L2DecodeComponent::start() {
     }
     mDecoderTaskRunner = mDecoderThread.task_runner();
     mWeakThis = mWeakThisFactory.GetWeakPtr();
-    mStdWeakThis = weak_from_this();
 
     c2_status_t status = C2_CORRUPTED;
     ::base::WaitableEvent done;
@@ -261,7 +260,7 @@ std::unique_ptr<VideoFramePool> V4L2DecodeComponent::getVideoFramePool(const ui:
     ALOGV("%s()", __func__);
     ALOG_ASSERT(mDecoderTaskRunner->RunsTasksInCurrentSequence());
 
-    auto sharedThis = mStdWeakThis.lock();
+    auto sharedThis = weak_from_this().lock();
     if (sharedThis == nullptr) {
         ALOGE("%s(): V4L2DecodeComponent instance is destroyed.", __func__);
         return nullptr;
@@ -348,7 +347,6 @@ void V4L2DecodeComponent::releaseTask() {
     ALOG_ASSERT(mDecoderTaskRunner->RunsTasksInCurrentSequence());
 
     mWeakThisFactory.InvalidateWeakPtrs();
-    mStdWeakThis.reset();
     mDecoder = nullptr;
 }
 
@@ -698,12 +696,6 @@ bool V4L2DecodeComponent::reportWork(std::unique_ptr<C2Work> work) {
     ALOGV("%s(work=%llu)", __func__, work->input.ordinal.frameIndex.peekull());
     ALOG_ASSERT(mDecoderTaskRunner->RunsTasksInCurrentSequence());
 
-    auto sharedThis = mStdWeakThis.lock();
-    if (sharedThis == nullptr) {
-        ALOGE("%s(): V4L2DecodeComponent instance is destroyed.", __func__);
-        return false;
-    }
-
     if (!mListener) {
         ALOGE("mListener is nullptr, setListener_vb() not called?");
         return false;
@@ -711,7 +703,7 @@ bool V4L2DecodeComponent::reportWork(std::unique_ptr<C2Work> work) {
 
     std::list<std::unique_ptr<C2Work>> finishedWorks;
     finishedWorks.emplace_back(std::move(work));
-    mListener->onWorkDone_nb(std::move(sharedThis), std::move(finishedWorks));
+    mListener->onWorkDone_nb(weak_from_this(), std::move(finishedWorks));
     return true;
 }
 
@@ -748,12 +740,6 @@ void V4L2DecodeComponent::reportAbandonedWorks() {
     ALOGV("%s()", __func__);
     ALOG_ASSERT(mDecoderTaskRunner->RunsTasksInCurrentSequence());
 
-    auto sharedThis = mStdWeakThis.lock();
-    if (sharedThis == nullptr) {
-        ALOGE("%s(): V4L2DecodeComponent instance is destroyed.", __func__);
-        return;
-    }
-
     std::list<std::unique_ptr<C2Work>> abandonedWorks;
     while (!mPendingWorks.empty()) {
         abandonedWorks.emplace_back(std::move(mPendingWorks.front()));
@@ -777,7 +763,7 @@ void V4L2DecodeComponent::reportAbandonedWorks() {
             ALOGE("mListener is nullptr, setListener_vb() not called?");
             return;
         }
-        mListener->onWorkDone_nb(std::move(sharedThis), std::move(abandonedWorks));
+        mListener->onWorkDone_nb(weak_from_this(), std::move(abandonedWorks));
     }
 }
 
@@ -851,12 +837,6 @@ void V4L2DecodeComponent::reportError(c2_status_t error) {
     ALOGE("%s(error=%u)", __func__, static_cast<uint32_t>(error));
     ALOG_ASSERT(mDecoderTaskRunner->RunsTasksInCurrentSequence());
 
-    auto sharedThis = mStdWeakThis.lock();
-    if (sharedThis == nullptr) {
-        ALOGE("%s(): V4L2DecodeComponent instance is destroyed.", __func__);
-        return;
-    }
-
     if (mComponentState.load() == ComponentState::ERROR) return;
     mComponentState.store(ComponentState::ERROR);
 
@@ -864,7 +844,7 @@ void V4L2DecodeComponent::reportError(c2_status_t error) {
         ALOGE("mListener is nullptr, setListener_vb() not called?");
         return;
     }
-    mListener->onError_nb(std::move(sharedThis), static_cast<uint32_t>(error));
+    mListener->onError_nb(weak_from_this(), static_cast<uint32_t>(error));
 }
 
 c2_status_t V4L2DecodeComponent::announce_nb(const std::vector<C2WorkOutline>& /* items */) {
diff --git a/components/V4L2EncodeComponent.cpp b/components/V4L2EncodeComponent.cpp
index f05ccab..a1b46ab 100644
--- a/components/V4L2EncodeComponent.cpp
+++ b/components/V4L2EncodeComponent.cpp
@@ -812,7 +812,7 @@ void V4L2EncodeComponent::flush() {
         mWorkQueue.pop_front();
     }
     if (!abortedWorkItems.empty()) {
-        mListener->onWorkDone_nb(shared_from_this(), std::move(abortedWorkItems));
+        mListener->onWorkDone_nb(weak_from_this(), std::move(abortedWorkItems));
     }
 }
 
@@ -1011,15 +1011,23 @@ void V4L2EncodeComponent::reportWork(std::unique_ptr<C2Work> work) {
 
     std::list<std::unique_ptr<C2Work>> finishedWorkList;
     finishedWorkList.emplace_back(std::move(work));
-    mListener->onWorkDone_nb(shared_from_this(), std::move(finishedWorkList));
+    mListener->onWorkDone_nb(weak_from_this(), std::move(finishedWorkList));
 }
 
 bool V4L2EncodeComponent::getBlockPool() {
+    ALOG_ASSERT(mEncoderTaskRunner->RunsTasksInCurrentSequence());
+
+    auto sharedThis = weak_from_this().lock();
+    if (!sharedThis) {
+        ALOGI("%s(): V4L2EncodeComponent instance is already destroyed", __func__);
+        return false;
+    }
+
     C2BlockPool::local_id_t poolId = mInterface->getBlockPoolId();
     if (poolId == C2BlockPool::BASIC_LINEAR) {
         ALOGW("Using unoptimized linear block pool");
     }
-    c2_status_t status = GetCodec2BlockPool(poolId, shared_from_this(), &mOutputBlockPool);
+    c2_status_t status = GetCodec2BlockPool(poolId, std::move(sharedThis), &mOutputBlockPool);
     if (status != C2_OK || !mOutputBlockPool) {
         ALOGE("Failed to get output block pool, error: %d", status);
         return false;
@@ -1035,7 +1043,7 @@ void V4L2EncodeComponent::reportError(c2_status_t error) {
     std::lock_guard<std::mutex> lock(mComponentLock);
     if (mComponentState != ComponentState::ERROR) {
         setComponentState(ComponentState::ERROR);
-        mListener->onError_nb(shared_from_this(), static_cast<uint32_t>(error));
+        mListener->onError_nb(weak_from_this(), static_cast<uint32_t>(error));
     }
 }
 
diff --git a/components/include/v4l2_codec2/components/V4L2DecodeComponent.h b/components/include/v4l2_codec2/components/V4L2DecodeComponent.h
index 1e98118..962f7d6 100644
--- a/components/include/v4l2_codec2/components/V4L2DecodeComponent.h
+++ b/components/include/v4l2_codec2/components/V4L2DecodeComponent.h
@@ -140,9 +140,6 @@ private:
     ::base::Thread mDecoderThread{"V4L2DecodeComponentDecoderThread"};
     scoped_refptr<::base::SequencedTaskRunner> mDecoderTaskRunner;
 
-    // Hold a weak_ptr of |*this| when |mDecoderThread| is running.
-    std::weak_ptr<V4L2DecodeComponent> mStdWeakThis;
-
     ::base::WeakPtrFactory<V4L2DecodeComponent> mWeakThisFactory{this};
     ::base::WeakPtr<V4L2DecodeComponent> mWeakThis;
 };