include/gui/IGraphicBufferConsumer.h - android_frameworks_native - Gitiles

 /*
  * Copyright (C) 2013 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_IGRAPHICBUFFERCONSUMER_H
 #define ANDROID_GUI_IGRAPHICBUFFERCONSUMER_H

 #include <stdint.h>
 #include <sys/types.h>

 #include <utils/Errors.h>
 #include <utils/RefBase.h>
 #include <utils/Timers.h>

 #include <binder/IInterface.h>

 #include <ui/PixelFormat.h>

 #include <gui/OccupancyTracker.h>

 #include <EGL/egl.h>
 #include <EGL/eglext.h>

 namespace android {
 // ----------------------------------------------------------------------------

 class BufferItem;
 class Fence;
 class GraphicBuffer;
 class IConsumerListener;
 class NativeHandle;

 class IGraphicBufferConsumer : public IInterface {

 public:
     enum {
         // Returned by releaseBuffer, after which the consumer must
         // free any references to the just-released buffer that it might have.
         STALE_BUFFER_SLOT = 1,
         // Returned by dequeueBuffer if there are no pending buffers available.
         NO_BUFFER_AVAILABLE,
         // Returned by dequeueBuffer if it's too early for the buffer to be acquired.
         PRESENT_LATER,
     };

     // 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 presentWhen is non-zero, 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.
     //
     // If maxFrameNumber is non-zero, it indicates that acquireBuffer should
     // only return a buffer with a frame number less than or equal to
     // maxFrameNumber. If no such frame is available (such as when a buffer has
     // been replaced but the consumer has not received the onFrameReplaced
     // callback), then PRESENT_LATER will be returned.
     //
     // Return of NO_ERROR means the operation completed as normal.
     //
     // Return of a positive value means the operation could not be completed
     //    at this time, but the user should try again later:
     // * NO_BUFFER_AVAILABLE - no buffer is pending (nothing queued by producer)
     // * PRESENT_LATER - the buffer's timestamp is farther in the future
     //
     // Return of a negative value means an error has occurred:
     // * INVALID_OPERATION - too many buffers have been acquired
     virtual status_t acquireBuffer(BufferItem* buffer, nsecs_t presentWhen,
             uint64_t maxFrameNumber = 0) = 0;

     // detachBuffer attempts to remove all ownership of the buffer in the given
     // slot from the buffer queue. If this call succeeds, the slot will be
     // freed, and there will be no way to obtain the buffer from this interface.
     // The freed slot will remain unallocated until either it is selected to
     // hold a freshly allocated buffer in dequeueBuffer or a buffer is attached
     // to the slot. The buffer must have already been acquired.
     //
     // Return of a value other than NO_ERROR means an error has occurred:
     // * BAD_VALUE - the given slot number is invalid, either because it is
     //               out of the range [0, NUM_BUFFER_SLOTS) or because the slot
     //               it refers to is not currently acquired.
     virtual status_t detachBuffer(int slot) = 0;

     // attachBuffer attempts to transfer ownership of a buffer to the buffer
     // queue. If this call succeeds, it will be as if this buffer was acquired
     // from the returned slot number. As such, this call will fail if attaching
     // this buffer would cause too many buffers to be simultaneously acquired.
     //
     // If the buffer is successfully attached, its frameNumber is initialized
     // to 0. This must be passed into the releaseBuffer call or else the buffer
     // will be deallocated as stale.
     //
     // Return of a value other than NO_ERROR means an error has occurred:
     // * BAD_VALUE - outSlot or buffer were NULL, or the generation number of
     //               the buffer did not match the buffer queue.
     // * INVALID_OPERATION - cannot attach the buffer because it would cause too
     //                       many buffers to be acquired.
     // * NO_MEMORY - no free slots available
     virtual status_t attachBuffer(int *outSlot,
             const sp<GraphicBuffer>& buffer) = 0;

     // 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.
     //
     // Return of NO_ERROR means the operation completed as normal.
     //
     // Return of a positive value means the operation could not be completed
     //    at this time, but the user should try again later:
     // * STALE_BUFFER_SLOT - see above (second paragraph)
     //
     // Return of a negative value means an error has occurred:
     // * BAD_VALUE - one of the following could've happened:
     //               * the buffer slot was invalid
     //               * the fence was NULL
     //               * the buffer slot specified is not in the acquired state
     virtual status_t releaseBuffer(int buf, uint64_t frameNumber,
             EGLDisplay display, EGLSyncKHR fence,
             const sp<Fence>& releaseFence) = 0;

     // consumerConnect 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.
     //
     // consumer may not be NULL.
     //
     // Return of a value other than NO_ERROR means an error has occurred:
     // * NO_INIT - the buffer queue has been abandoned
     // * BAD_VALUE - a NULL consumer was provided
     virtual status_t consumerConnect(const sp<IConsumerListener>& consumer, bool controlledByApp) = 0;

     // consumerDisconnect 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.
     //
     // Return of a value other than NO_ERROR means an error has occurred:
     // * BAD_VALUE - no consumer is currently connected
     virtual status_t consumerDisconnect() = 0;

     // getReleasedBuffers sets the value pointed to by slotMask to a bit set.
     // Each bit index with a 1 corresponds to a released buffer slot with that
     // index value.  In particular, a released buffer is one that has
     // been released by the BufferQueue but have not yet been released by the consumer.
     //
     // This should be called from the onBuffersReleased() callback.
     //
     // Return of a value other than NO_ERROR means an error has occurred:
     // * NO_INIT - the buffer queue has been abandoned.
     virtual status_t getReleasedBuffers(uint64_t* slotMask) = 0;

     // setDefaultBufferSize is used to set the size of buffers returned by
     // dequeueBuffer when a width and height of zero is requested.  Default
     // is 1x1.
     //
     // Return of a value other than NO_ERROR means an error has occurred:
     // * BAD_VALUE - either w or h was zero
     virtual status_t setDefaultBufferSize(uint32_t w, uint32_t h) = 0;

     // setMaxBufferCount sets the maximum value for the number of buffers used
     // in the buffer queue (the initial default is NUM_BUFFER_SLOTS). If a call
     // to setMaxAcquiredBufferCount (by the consumer), or a call to setAsyncMode
     // or setMaxDequeuedBufferCount (by the producer), would cause this value to
     // be exceeded then that call will fail. This call will fail if a producer
     // is connected to the BufferQueue.
     //
     // The count must be between 1 and NUM_BUFFER_SLOTS, inclusive. The count
     // cannot be less than maxAcquiredBufferCount.
     //
     // Return of a value other than NO_ERROR means an error has occurred:
     // * BAD_VALUE - one of the below conditions occurred:
     //             * bufferCount was out of range (see above).
     //             * failure to adjust the number of available slots.
     // * INVALID_OPERATION - attempting to call this after a producer connected.
     virtual status_t setMaxBufferCount(int bufferCount) = 0;

     // setMaxAcquiredBufferCount sets the maximum number of buffers that can
     // be acquired by the consumer at one time (default 1). If this method
     // succeeds, any new buffer slots will be both unallocated and owned by the
     // BufferQueue object (i.e. they are not owned by the producer or consumer).
     // Calling this may also cause some buffer slots to be emptied.
     //
     // This function should not be called with a value of maxAcquiredBuffers
     // that is less than the number of currently acquired buffer slots. Doing so
     // will result in a BAD_VALUE error.
     //
     // maxAcquiredBuffers must be (inclusive) between 1 and
     // MAX_MAX_ACQUIRED_BUFFERS. It also cannot cause the maxBufferCount value
     // to be exceeded.
     //
     // Return of a value other than NO_ERROR means an error has occurred:
     // * NO_INIT - the buffer queue has been abandoned
     // * BAD_VALUE - one of the below conditions occurred:
     //             * maxAcquiredBuffers was out of range (see above).
     //             * failure to adjust the number of available slots.
     //             * client would have more than the requested number of
     //               acquired buffers after this call
     // * INVALID_OPERATION - attempting to call this after a producer connected.
     virtual status_t setMaxAcquiredBufferCount(int maxAcquiredBuffers) = 0;

     // setConsumerName sets the name used in logging
     virtual void setConsumerName(const String8& name) = 0;

     // setDefaultBufferFormat allows the BufferQueue to create
     // GraphicBuffers of a defaultFormat if no format is specified
     // in dequeueBuffer.
     // The initial default is PIXEL_FORMAT_RGBA_8888.
     //
     // Return of a value other than NO_ERROR means an unknown error has occurred.
     virtual status_t setDefaultBufferFormat(PixelFormat defaultFormat) = 0;

     // setDefaultBufferDataSpace is a request to the producer to provide buffers
     // of the indicated dataSpace. The producer may ignore this request.
     // The initial default is HAL_DATASPACE_UNKNOWN.
     //
     // Return of a value other than NO_ERROR means an unknown error has occurred.
     virtual status_t setDefaultBufferDataSpace(
             android_dataspace defaultDataSpace) = 0;

     // 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.
     //
     // Return of a value other than NO_ERROR means an unknown error has occurred.
     virtual status_t setConsumerUsageBits(uint32_t usage) = 0;

     // 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).
     //
     // Return of a value other than NO_ERROR means an unknown error has occurred.
     virtual status_t setTransformHint(uint32_t hint) = 0;

     // Retrieve the sideband buffer stream, if any.
     virtual sp<NativeHandle> getSidebandStream() const = 0;

     // Retrieves any stored segments of the occupancy history of this
     // BufferQueue and clears them. Optionally closes out the pending segment if
     // forceFlush is true.
     virtual status_t getOccupancyHistory(bool forceFlush,
             std::vector<OccupancyTracker::Segment>* outHistory) = 0;

     // discardFreeBuffers releases all currently-free buffers held by the queue,
     // in order to reduce the memory consumption of the queue to the minimum
     // possible without discarding data.
     virtual status_t discardFreeBuffers() = 0;

     // dump state into a string
     virtual void dumpState(String8& result, const char* prefix) const = 0;

 public:
     DECLARE_META_INTERFACE(GraphicBufferConsumer)
 };

 // ----------------------------------------------------------------------------

 class BnGraphicBufferConsumer : public BnInterface<IGraphicBufferConsumer>
 {
 public:
     virtual status_t    onTransact( uint32_t code,
                                     const Parcel& data,
                                     Parcel* reply,
                                     uint32_t flags = 0);
 };

 // ----------------------------------------------------------------------------
 }; // namespace android

 #endif // ANDROID_GUI_IGRAPHICBUFFERCONSUMER_H
	/*
	* Copyright (C) 2013 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_IGRAPHICBUFFERCONSUMER_H
	#define ANDROID_GUI_IGRAPHICBUFFERCONSUMER_H

	#include <stdint.h>
	#include <sys/types.h>

	#include <utils/Errors.h>
	#include <utils/RefBase.h>
	#include <utils/Timers.h>

	#include <binder/IInterface.h>

	#include <ui/PixelFormat.h>

	#include <gui/OccupancyTracker.h>

	#include <EGL/egl.h>
	#include <EGL/eglext.h>

	namespace android {
	// ----------------------------------------------------------------------------

	class BufferItem;
	class Fence;
	class GraphicBuffer;
	class IConsumerListener;
	class NativeHandle;

	class IGraphicBufferConsumer : public IInterface {

	public:
	enum {
	// Returned by releaseBuffer, after which the consumer must
	// free any references to the just-released buffer that it might have.
	STALE_BUFFER_SLOT = 1,
	// Returned by dequeueBuffer if there are no pending buffers available.
	NO_BUFFER_AVAILABLE,
	// Returned by dequeueBuffer if it's too early for the buffer to be acquired.
	PRESENT_LATER,
	};

	// 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 presentWhen is non-zero, 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.
	//
	// If maxFrameNumber is non-zero, it indicates that acquireBuffer should
	// only return a buffer with a frame number less than or equal to
	// maxFrameNumber. If no such frame is available (such as when a buffer has
	// been replaced but the consumer has not received the onFrameReplaced
	// callback), then PRESENT_LATER will be returned.
	//
	// Return of NO_ERROR means the operation completed as normal.
	//
	// Return of a positive value means the operation could not be completed
	// at this time, but the user should try again later:
	// * NO_BUFFER_AVAILABLE - no buffer is pending (nothing queued by producer)
	// * PRESENT_LATER - the buffer's timestamp is farther in the future
	//
	// Return of a negative value means an error has occurred:
	// * INVALID_OPERATION - too many buffers have been acquired
	virtual status_t acquireBuffer(BufferItem* buffer, nsecs_t presentWhen,
	uint64_t maxFrameNumber = 0) = 0;

	// detachBuffer attempts to remove all ownership of the buffer in the given
	// slot from the buffer queue. If this call succeeds, the slot will be
	// freed, and there will be no way to obtain the buffer from this interface.
	// The freed slot will remain unallocated until either it is selected to
	// hold a freshly allocated buffer in dequeueBuffer or a buffer is attached
	// to the slot. The buffer must have already been acquired.
	//
	// Return of a value other than NO_ERROR means an error has occurred:
	// * BAD_VALUE - the given slot number is invalid, either because it is
	// out of the range [0, NUM_BUFFER_SLOTS) or because the slot
	// it refers to is not currently acquired.
	virtual status_t detachBuffer(int slot) = 0;

	// attachBuffer attempts to transfer ownership of a buffer to the buffer
	// queue. If this call succeeds, it will be as if this buffer was acquired
	// from the returned slot number. As such, this call will fail if attaching
	// this buffer would cause too many buffers to be simultaneously acquired.
	//
	// If the buffer is successfully attached, its frameNumber is initialized
	// to 0. This must be passed into the releaseBuffer call or else the buffer
	// will be deallocated as stale.
	//
	// Return of a value other than NO_ERROR means an error has occurred:
	// * BAD_VALUE - outSlot or buffer were NULL, or the generation number of
	// the buffer did not match the buffer queue.
	// * INVALID_OPERATION - cannot attach the buffer because it would cause too
	// many buffers to be acquired.
	// * NO_MEMORY - no free slots available
	virtual status_t attachBuffer(int *outSlot,
	const sp<GraphicBuffer>& buffer) = 0;

	// 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.
	//
	// Return of NO_ERROR means the operation completed as normal.
	//
	// Return of a positive value means the operation could not be completed
	// at this time, but the user should try again later:
	// * STALE_BUFFER_SLOT - see above (second paragraph)
	//
	// Return of a negative value means an error has occurred:
	// * BAD_VALUE - one of the following could've happened:
	// * the buffer slot was invalid
	// * the fence was NULL
	// * the buffer slot specified is not in the acquired state
	virtual status_t releaseBuffer(int buf, uint64_t frameNumber,
	EGLDisplay display, EGLSyncKHR fence,
	const sp<Fence>& releaseFence) = 0;

	// consumerConnect 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.
	//
	// consumer may not be NULL.
	//
	// Return of a value other than NO_ERROR means an error has occurred:
	// * NO_INIT - the buffer queue has been abandoned
	// * BAD_VALUE - a NULL consumer was provided
	virtual status_t consumerConnect(const sp<IConsumerListener>& consumer, bool controlledByApp) = 0;

	// consumerDisconnect 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.
	//
	// Return of a value other than NO_ERROR means an error has occurred:
	// * BAD_VALUE - no consumer is currently connected
	virtual status_t consumerDisconnect() = 0;

	// getReleasedBuffers sets the value pointed to by slotMask to a bit set.
	// Each bit index with a 1 corresponds to a released buffer slot with that
	// index value. In particular, a released buffer is one that has
	// been released by the BufferQueue but have not yet been released by the consumer.
	//
	// This should be called from the onBuffersReleased() callback.
	//
	// Return of a value other than NO_ERROR means an error has occurred:
	// * NO_INIT - the buffer queue has been abandoned.
	virtual status_t getReleasedBuffers(uint64_t* slotMask) = 0;

	// setDefaultBufferSize is used to set the size of buffers returned by
	// dequeueBuffer when a width and height of zero is requested. Default
	// is 1x1.
	//
	// Return of a value other than NO_ERROR means an error has occurred:
	// * BAD_VALUE - either w or h was zero
	virtual status_t setDefaultBufferSize(uint32_t w, uint32_t h) = 0;

	// setMaxBufferCount sets the maximum value for the number of buffers used
	// in the buffer queue (the initial default is NUM_BUFFER_SLOTS). If a call
	// to setMaxAcquiredBufferCount (by the consumer), or a call to setAsyncMode
	// or setMaxDequeuedBufferCount (by the producer), would cause this value to
	// be exceeded then that call will fail. This call will fail if a producer
	// is connected to the BufferQueue.
	//
	// The count must be between 1 and NUM_BUFFER_SLOTS, inclusive. The count
	// cannot be less than maxAcquiredBufferCount.
	//
	// Return of a value other than NO_ERROR means an error has occurred:
	// * BAD_VALUE - one of the below conditions occurred:
	// * bufferCount was out of range (see above).
	// * failure to adjust the number of available slots.
	// * INVALID_OPERATION - attempting to call this after a producer connected.
	virtual status_t setMaxBufferCount(int bufferCount) = 0;

	// setMaxAcquiredBufferCount sets the maximum number of buffers that can
	// be acquired by the consumer at one time (default 1). If this method
	// succeeds, any new buffer slots will be both unallocated and owned by the
	// BufferQueue object (i.e. they are not owned by the producer or consumer).
	// Calling this may also cause some buffer slots to be emptied.
	//
	// This function should not be called with a value of maxAcquiredBuffers
	// that is less than the number of currently acquired buffer slots. Doing so
	// will result in a BAD_VALUE error.
	//
	// maxAcquiredBuffers must be (inclusive) between 1 and
	// MAX_MAX_ACQUIRED_BUFFERS. It also cannot cause the maxBufferCount value
	// to be exceeded.
	//
	// Return of a value other than NO_ERROR means an error has occurred:
	// * NO_INIT - the buffer queue has been abandoned
	// * BAD_VALUE - one of the below conditions occurred:
	// * maxAcquiredBuffers was out of range (see above).
	// * failure to adjust the number of available slots.
	// * client would have more than the requested number of
	// acquired buffers after this call
	// * INVALID_OPERATION - attempting to call this after a producer connected.
	virtual status_t setMaxAcquiredBufferCount(int maxAcquiredBuffers) = 0;

	// setConsumerName sets the name used in logging
	virtual void setConsumerName(const String8& name) = 0;

	// setDefaultBufferFormat allows the BufferQueue to create
	// GraphicBuffers of a defaultFormat if no format is specified
	// in dequeueBuffer.
	// The initial default is PIXEL_FORMAT_RGBA_8888.
	//
	// Return of a value other than NO_ERROR means an unknown error has occurred.
	virtual status_t setDefaultBufferFormat(PixelFormat defaultFormat) = 0;

	// setDefaultBufferDataSpace is a request to the producer to provide buffers
	// of the indicated dataSpace. The producer may ignore this request.
	// The initial default is HAL_DATASPACE_UNKNOWN.
	//
	// Return of a value other than NO_ERROR means an unknown error has occurred.
	virtual status_t setDefaultBufferDataSpace(
	android_dataspace defaultDataSpace) = 0;

	// 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.
	//
	// Return of a value other than NO_ERROR means an unknown error has occurred.
	virtual status_t setConsumerUsageBits(uint32_t usage) = 0;

	// 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).
	//
	// Return of a value other than NO_ERROR means an unknown error has occurred.
	virtual status_t setTransformHint(uint32_t hint) = 0;

	// Retrieve the sideband buffer stream, if any.
	virtual sp<NativeHandle> getSidebandStream() const = 0;

	// Retrieves any stored segments of the occupancy history of this
	// BufferQueue and clears them. Optionally closes out the pending segment if
	// forceFlush is true.
	virtual status_t getOccupancyHistory(bool forceFlush,
	std::vector<OccupancyTracker::Segment>* outHistory) = 0;

	// discardFreeBuffers releases all currently-free buffers held by the queue,
	// in order to reduce the memory consumption of the queue to the minimum
	// possible without discarding data.
	virtual status_t discardFreeBuffers() = 0;

	// dump state into a string
	virtual void dumpState(String8& result, const char* prefix) const = 0;

	public:
	DECLARE_META_INTERFACE(GraphicBufferConsumer)
	};

	// ----------------------------------------------------------------------------

	class BnGraphicBufferConsumer : public BnInterface<IGraphicBufferConsumer>
	{
	public:
	virtual status_t onTransact( uint32_t code,
	const Parcel& data,
	Parcel* reply,
	uint32_t flags = 0);
	};

	// ----------------------------------------------------------------------------
	}; // namespace android

	#endif // ANDROID_GUI_IGRAPHICBUFFERCONSUMER_H