text: /*
   * Copyright 2014 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_BUFFERQUEUECONSUMER_H
  #define ANDROID_GUI_BUFFERQUEUECONSUMER_H
  
  #include <EGL/egl.h>
  #include <EGL/eglext.h>
  
  #include <gui/BufferQueueDefs.h>
  #include <gui/IGraphicBufferConsumer.h>
  
  namespace android {
  
  class BufferQueueCore;
  
  class BufferQueueConsumer : public BnGraphicBufferConsumer {
  
  public:
      BufferQueueConsumer(const sp<BufferQueueCore>& core);
      virtual ~BufferQueueConsumer();
  
      // acquireBuffer attempts to acquire ownership of the next pending buffer in
      // the BufferQueue. If no buffer is pending then it returns
      // NO_BUFFER_AVAILABLE. If a buffer is successfully acquired, the
      // information about the buffer is returned in BufferItem.  If the buffer
      // returned had previously been acquired then the BufferItem::mGraphicBuffer
      // field of buffer is set to NULL and it is assumed that the consumer still
      // holds a reference to the buffer.
      //
      // If expectedPresent is nonzero, it indicates the time when the buffer
      // will be displayed on screen. If the buffer's timestamp is farther in the
      // future, the buffer won't be acquired, and PRESENT_LATER will be
      // returned.  The presentation time is in nanoseconds, and the time base
      // is CLOCK_MONOTONIC.
      virtual status_t acquireBuffer(BufferItem* outBuffer,
              nsecs_t expectedPresent, uint64_t maxFrameNumber = 0) override;
  
      // See IGraphicBufferConsumer::detachBuffer
      virtual status_t detachBuffer(int slot);
  
      // See IGraphicBufferConsumer::attachBuffer
      virtual status_t attachBuffer(int* slot, const sp<GraphicBuffer>& buffer);
  
      // releaseBuffer releases a buffer slot from the consumer back to the
      // BufferQueue.  This may be done while the buffer's contents are still
      // being accessed.  The fence will signal when the buffer is no longer
      // in use. frameNumber is used to indentify the exact buffer returned.
      //
      // If releaseBuffer returns STALE_BUFFER_SLOT, then the consumer must free
      // any references to the just-released buffer that it might have, as if it
      // had received a onBuffersReleased() call with a mask set for the released
      // buffer.
      //
      // Note that the dependencies on EGL will be removed once we switch to using
      // the Android HW Sync HAL.
      virtual status_t releaseBuffer(int slot, uint64_t frameNumber,
              const sp<Fence>& releaseFence, EGLDisplay display,
              EGLSyncKHR fence);
  
      // connect connects a consumer to the BufferQueue.  Only one
      // consumer may be connected, and when that consumer disconnects the
      // BufferQueue is placed into the "abandoned" state, causing most
      // interactions with the BufferQueue by the producer to fail.
      // controlledByApp indicates whether the consumer is controlled by
      // the application.
      //
      // consumerListener may not be NULL.
      virtual status_t connect(const sp<IConsumerListener>& consumerListener,
              bool controlledByApp);
  
      // disconnect disconnects a consumer from the BufferQueue. All
      // buffers will be freed and the BufferQueue is placed in the "abandoned"
      // state, causing most interactions with the BufferQueue by the producer to
      // fail.
      virtual status_t disconnect();
  
      // getReleasedBuffers sets the value pointed to by outSlotMask to a bit mask
      // indicating which buffer slots have been released by the BufferQueue
      // but have not yet been released by the consumer.
      //
      // This should be called from the onBuffersReleased() callback.
      virtual status_t getReleasedBuffers(uint64_t* outSlotMask);
  
      // setDefaultBufferSize is used to set the size of buffers returned by
      // dequeueBuffer when a width and height of zero is requested.  Default
      // is 1x1.
      virtual status_t setDefaultBufferSize(uint32_t width, uint32_t height);
  
      // setDefaultMaxBufferCount sets the default value for the maximum buffer
      // count (the initial default is 2). If the producer has requested a
      // buffer count using setBufferCount, the default buffer count will only
      // take effect if the producer sets the count back to zero.
      //
      // The count must be between 2 and NUM_BUFFER_SLOTS, inclusive.
      virtual status_t setDefaultMaxBufferCount(int bufferCount);
  
      // disableAsyncBuffer disables the extra buffer used in async mode
      // (when both producer and consumer have set their "isControlledByApp"
      // flag) and has dequeueBuffer() return WOULD_BLOCK instead.
      //
      // This can only be called before connect().
      virtual status_t disableAsyncBuffer();
  
      // setMaxAcquiredBufferCount sets the maximum number of buffers that can
      // be acquired by the consumer at one time (default 1).  This call will
      // fail if a producer is connected to the BufferQueue.
      virtual status_t setMaxAcquiredBufferCount(int maxAcquiredBuffers);
  
      // setConsumerName sets the name used in logging
      virtual void setConsumerName(const String8& name);
  
      // setDefaultBufferFormat allows the BufferQueue to create
      // GraphicBuffers of a defaultFormat if no format is specified
      // in dequeueBuffer. The initial default is HAL_PIXEL_FORMAT_RGBA_8888.
      virtual status_t setDefaultBufferFormat(PixelFormat defaultFormat);
  
      // setDefaultBufferDataSpace allows the BufferQueue to create
      // GraphicBuffers of a defaultDataSpace if no data space is specified
      // in queueBuffer.
      // The initial default is HAL_DATASPACE_UNKNOWN
      virtual status_t setDefaultBufferDataSpace(
              android_dataspace defaultDataSpace);
  
      // setConsumerUsageBits will turn on additional usage bits for dequeueBuffer.
      // These are merged with the bits passed to dequeueBuffer.  The values are
      // enumerated in gralloc.h, e.g. GRALLOC_USAGE_HW_RENDER; the default is 0.
      virtual status_t setConsumerUsageBits(uint32_t usage);
  
      // setTransformHint bakes in rotation to buffers so overlays can be used.
      // The values are enumerated in window.h, e.g.
      // NATIVE_WINDOW_TRANSFORM_ROT_90.  The default is 0 (no transform).
      virtual status_t setTransformHint(uint32_t hint);
  
      // Retrieve the sideband buffer stream, if any.
      virtual sp<NativeHandle> getSidebandStream() const;
  
      // dump our state in a String
      virtual void dump(String8& result, const char* prefix) const;
  
      // Functions required for backwards compatibility.
      // These will be modified/renamed in IGraphicBufferConsumer and will be
      // removed from this class at that time. See b/13306289.
  
      virtual status_t releaseBuffer(int buf, uint64_t frameNumber,
              EGLDisplay display, EGLSyncKHR fence,
              const sp<Fence>& releaseFence) {
          return releaseBuffer(buf, frameNumber, releaseFence, display, fence);
      }
  
      virtual status_t consumerConnect(const sp<IConsumerListener>& consumer,
              bool controlledByApp) {
          return connect(consumer, controlledByApp);
      }
  
      virtual status_t consumerDisconnect() { return disconnect(); }
  
      // End functions required for backwards compatibility
  
  private:
      sp<BufferQueueCore> mCore;
  
      // This references mCore->mSlots. Lock mCore->mMutex while accessing.
      BufferQueueDefs::SlotsType& mSlots;
  
      // This is a cached copy of the name stored in the BufferQueueCore.
      // It's updated during setConsumerName.
      String8 mConsumerName;
  
  }; // class BufferQueueConsumer
  
  } // namespace android
  
  #endif
  