Merge "Surface: Add 'isBufferOwned' call" into main

Author: Jim Shargo

libs/gui/Surface.cpp

@@ -2230,17 +2230,47 @@ int Surface::detachNextBuffer(sp<GraphicBuffer>* outBuffer,
     return NO_ERROR;
 }
 
+int Surface::isBufferOwned(const sp<GraphicBuffer>& buffer, bool* outIsOwned) const {
+    ATRACE_CALL();
+
+    if (buffer == nullptr) {
+        ALOGE("%s: Bad input, buffer was null", __FUNCTION__);
+        return BAD_VALUE;
+    }
+    if (outIsOwned == nullptr) {
+        ALOGE("%s: Bad input, output was null", __FUNCTION__);
+        return BAD_VALUE;
+    }
+
+    Mutex::Autolock lock(mMutex);
+
+    int slot = this->getSlotFromBufferLocked(buffer->getNativeBuffer());
+    if (slot == BAD_VALUE) {
+        ALOGV("%s: Buffer %" PRIu64 " is not owned", __FUNCTION__, buffer->getId());
+        *outIsOwned = false;
+        return NO_ERROR;
+    } else if (slot < 0) {
+        ALOGV("%s: Buffer %" PRIu64 " look up failed (%d)", __FUNCTION__, buffer->getId(), slot);
+        *outIsOwned = false;
+        return slot;
+    }
+
+    *outIsOwned = true;
+    return NO_ERROR;
+}
+
 int Surface::attachBuffer(ANativeWindowBuffer* buffer)
 {
     ATRACE_CALL();
-    ALOGV("Surface::attachBuffer");
+    sp<GraphicBuffer> graphicBuffer(static_cast<GraphicBuffer*>(buffer));
+
+    ALOGV("Surface::attachBuffer bufferId=%" PRIu64, graphicBuffer->getId());
 
     Mutex::Autolock lock(mMutex);
     if (mReportRemovedBuffers) {
         mRemovedBuffers.clear();
     }
 
-    sp<GraphicBuffer> graphicBuffer(static_cast<GraphicBuffer*>(buffer));
     uint32_t priorGeneration = graphicBuffer->mGenerationNumber;
     graphicBuffer->mGenerationNumber = mGenerationNumber;
     int32_t attachedSlot = -1;

libs/gui/include/gui/Surface.h

@@ -442,6 +442,9 @@ class Surface
     status_t detachBuffer(const sp<GraphicBuffer>& buffer);
 #endif // COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_PLATFORM_API_IMPROVEMENTS)
 
+    // Sets outIsOwned to true if the given buffer is currently known to be owned by this Surface.
+    status_t isBufferOwned(const sp<GraphicBuffer>& buffer, bool* outIsOwned) const;
+
     // Batch version of dequeueBuffer, cancelBuffer and queueBuffer
     // Note that these batched operations are not supported when shared buffer mode is being used.
     struct BatchBuffer {

libs/gui/tests/Surface_test.cpp

@@ -2699,4 +2699,57 @@ TEST_F(SurfaceTest, UnlimitedSlots_BatchOperations) {
     EXPECT_EQ(128u, outputs.size());
 }
 #endif // COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_UNLIMITED_SLOTS)
+
+TEST_F(SurfaceTest, isBufferOwned) {
+    const int TEST_USAGE_FLAGS = GRALLOC_USAGE_SW_READ_OFTEN | GRALLOC_USAGE_HW_RENDER;
+    auto [bufferItemConsumer, surface] = BufferItemConsumer::create(TEST_USAGE_FLAGS);
+
+    sp<SurfaceListener> listener = sp<StubSurfaceListener>::make();
+    ASSERT_EQ(OK, surface->connect(NATIVE_WINDOW_API_CPU, listener));
+
+    sp<GraphicBuffer> surfaceAttachableBuffer =
+            sp<GraphicBuffer>::make(10, 10, PIXEL_FORMAT_RGBA_8888, 1, TEST_USAGE_FLAGS);
+
+    //
+    // Attaching a buffer makes it owned.
+    //
+
+    bool isOwned;
+    EXPECT_EQ(OK, surface->isBufferOwned(surfaceAttachableBuffer, &isOwned));
+    EXPECT_FALSE(isOwned);
+
+    EXPECT_EQ(OK, surface->attachBuffer(surfaceAttachableBuffer.get()));
+    EXPECT_EQ(OK, surface->isBufferOwned(surfaceAttachableBuffer, &isOwned));
+    EXPECT_TRUE(isOwned);
+
+    //
+    // A dequeued buffer is always owned.
+    //
+
+    sp<GraphicBuffer> buffer;
+    sp<Fence> fence;
+    EXPECT_EQ(OK, surface->dequeueBuffer(&buffer, &fence));
+    EXPECT_EQ(OK, surface->isBufferOwned(buffer, &isOwned));
+    EXPECT_TRUE(isOwned);
+
+    //
+    // A detached buffer is no longer owned.
+    //
+
+    EXPECT_EQ(OK, surface->detachBuffer(buffer));
+    EXPECT_EQ(OK, surface->isBufferOwned(buffer, &isOwned));
+    EXPECT_FALSE(isOwned);
+
+    //
+    // It's not currently possible to verify whether or not a consumer has attached a buffer until
+    // it shows up on the Surface.
+    //
+
+    sp<GraphicBuffer> consumerAttachableBuffer =
+            sp<GraphicBuffer>::make(10, 10, PIXEL_FORMAT_RGBA_8888, 1, TEST_USAGE_FLAGS);
+
+    ASSERT_EQ(OK, bufferItemConsumer->attachBuffer(consumerAttachableBuffer));
+    EXPECT_EQ(OK, surface->isBufferOwned(consumerAttachableBuffer, &isOwned));
+    EXPECT_FALSE(isOwned);
+}
 } // namespace android