| /* |
| * Copyright (C) 2012 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #ifndef ANDROID_GUI_BUFFERQUEUE_H |
| #define ANDROID_GUI_BUFFERQUEUE_H |
| |
| #include <gui/BufferItem.h> |
| #include <gui/BufferQueueDefs.h> |
| #include <gui/IGraphicBufferConsumer.h> |
| #include <gui/IGraphicBufferProducer.h> |
| #include <gui/IConsumerListener.h> |
| |
| // These are only required to keep other parts of the framework with incomplete |
| // dependencies building successfully |
| #include <gui/IGraphicBufferAlloc.h> |
| |
| namespace android { |
| |
| class BufferQueue { |
| public: |
| // BufferQueue will keep track of at most this value of buffers. |
| // Attempts at runtime to increase the number of buffers past this will fail. |
| enum { NUM_BUFFER_SLOTS = BufferQueueDefs::NUM_BUFFER_SLOTS }; |
| // Used as a placeholder slot# when the value isn't pointing to an existing buffer. |
| enum { INVALID_BUFFER_SLOT = BufferItem::INVALID_BUFFER_SLOT }; |
| // Alias to <IGraphicBufferConsumer.h> -- please scope from there in future code! |
| enum { |
| NO_BUFFER_AVAILABLE = IGraphicBufferConsumer::NO_BUFFER_AVAILABLE, |
| PRESENT_LATER = IGraphicBufferConsumer::PRESENT_LATER, |
| }; |
| |
| // When in async mode we reserve two slots in order to guarantee that the |
| // producer and consumer can run asynchronously. |
| enum { MAX_MAX_ACQUIRED_BUFFERS = NUM_BUFFER_SLOTS - 2 }; |
| |
| // for backward source compatibility |
| typedef ::android::ConsumerListener ConsumerListener; |
| |
| // ProxyConsumerListener is a ConsumerListener implementation that keeps a weak |
| // reference to the actual consumer object. It forwards all calls to that |
| // consumer object so long as it exists. |
| // |
| // This class exists to avoid having a circular reference between the |
| // BufferQueue object and the consumer object. The reason this can't be a weak |
| // reference in the BufferQueue class is because we're planning to expose the |
| // consumer side of a BufferQueue as a binder interface, which doesn't support |
| // weak references. |
| class ProxyConsumerListener : public BnConsumerListener { |
| public: |
| explicit ProxyConsumerListener(const wp<ConsumerListener>& consumerListener); |
| virtual ~ProxyConsumerListener(); |
| virtual void onFrameAvailable(const BufferItem& item) override; |
| virtual void onFrameReplaced(const BufferItem& item) override; |
| virtual void onBuffersReleased() override; |
| virtual void onSidebandStreamChanged() override; |
| private: |
| // mConsumerListener is a weak reference to the IConsumerListener. This is |
| // the raison d'etre of ProxyConsumerListener. |
| wp<ConsumerListener> mConsumerListener; |
| }; |
| |
| // BufferQueue manages a pool of gralloc memory slots to be used by |
| // producers and consumers. allocator is used to allocate all the |
| // needed gralloc buffers. |
| static void createBufferQueue(sp<IGraphicBufferProducer>* outProducer, |
| sp<IGraphicBufferConsumer>* outConsumer, |
| const sp<IGraphicBufferAlloc>& allocator = NULL); |
| |
| private: |
| BufferQueue(); // Create through createBufferQueue |
| }; |
| |
| // ---------------------------------------------------------------------------- |
| }; // namespace android |
| |
| #endif // ANDROID_GUI_BUFFERQUEUE_H |