The Tor Browser: widget/gonk/nativewindow/GonkBufferQueueJB.h@6474c204b198 (annotated)

widget/gonk/nativewindow/GonkBufferQueueJB.h@6474c204b198 (annotated)

widget/gonk/nativewindow/GonkBufferQueueJB.h

Wed, 31 Dec 2014 06:09:35 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Wed, 31 Dec 2014 06:09:35 +0100
changeset 0: 6474c204b198
permissions: -rwxr-xr-x

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

 /*
  * Copyright (C) 2012 The Android Open Source Project
  * Copyright (C) 2013 Mozilla Foundation
  *
  * 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 NATIVEWINDOW_GONKBUFFERQUEUE_JB_H
 #define NATIVEWINDOW_GONKBUFFERQUEUE_JB_H
 #include <gui/IGraphicBufferAlloc.h>
 #if ANDROID_VERSION == 17
 #include <gui/ISurfaceTexture.h>
 #else
 #include <gui/IGraphicBufferProducer.h>
 #endif
 #include <ui/Fence.h>
 #include <ui/GraphicBuffer.h>
 #include <utils/String8.h>
 #include <utils/Vector.h>
 #include <utils/threads.h>
 #include "mozilla/layers/LayersSurfaces.h"
 #include "mozilla/layers/TextureClient.h"
 #if ANDROID_VERSION == 17
 #define IGraphicBufferProducer ISurfaceTexture
 #endif
 namespace android {
 // ----------------------------------------------------------------------------
 #if ANDROID_VERSION == 17
 class GonkBufferQueue : public BnSurfaceTexture {
 #else
 class GonkBufferQueue : public BnGraphicBufferProducer {
 #endif
     typedef mozilla::layers::TextureClient TextureClient;
 public:
     enum { MIN_UNDEQUEUED_BUFFERS = 2 };
     enum { NUM_BUFFER_SLOTS = 32 };
     enum { NO_CONNECTED_API = 0 };
     enum { INVALID_BUFFER_SLOT = -1 };
     enum { STALE_BUFFER_SLOT = 1, NO_BUFFER_AVAILABLE };
     // 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 };
     // ConsumerListener is the interface through which the GonkBufferQueue notifies
     // the consumer of events that the consumer may wish to react to.  Because
     // the consumer will generally have a mutex that is locked during calls from
     // the consumer to the GonkBufferQueue, these calls from the GonkBufferQueue to the
     // consumer *MUST* be called only when the GonkBufferQueue mutex is NOT locked.
     struct ConsumerListener : public virtual RefBase {
         // onFrameAvailable is called from queueBuffer each time an additional
         // frame becomes available for consumption. This means that frames that
         // are queued while in asynchronous mode only trigger the callback if no
         // previous frames are pending. Frames queued while in synchronous mode
         // always trigger the callback.
         //
         // This is called without any lock held and can be called concurrently
         // by multiple threads.
         virtual void onFrameAvailable() = 0;
         // onBuffersReleased is called to notify the buffer consumer that the
         // GonkBufferQueue has released its references to one or more GraphicBuffers
         // contained in its slots.  The buffer consumer should then call
         // GonkBufferQueue::getReleasedBuffers to retrieve the list of buffers
         //
         // This is called without any lock held and can be called concurrently
         // by multiple threads.
         virtual void onBuffersReleased() = 0;
     };
     // 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
     // GonkBufferQueue object and the consumer object.  The reason this can't be a weak
     // reference in the GonkBufferQueue class is because we're planning to expose the
     // consumer side of a GonkBufferQueue as a binder interface, which doesn't support
     // weak references.
     class ProxyConsumerListener : public GonkBufferQueue::ConsumerListener {
     public:
         ProxyConsumerListener(const wp<GonkBufferQueue::ConsumerListener>& consumerListener);
         virtual ~ProxyConsumerListener();
         virtual void onFrameAvailable();
         virtual void onBuffersReleased();
     private:
         // mConsumerListener is a weak reference to the ConsumerListener.  This is
         // the raison d'etre of ProxyConsumerListener.
         wp<GonkBufferQueue::ConsumerListener> mConsumerListener;
     };
     // GonkBufferQueue manages a pool of gralloc memory slots to be used by
     // producers and consumers. allowSynchronousMode specifies whether or not
     // synchronous mode can be enabled by the producer. allocator is used to
     // allocate all the needed gralloc buffers.
     GonkBufferQueue(bool allowSynchronousMode = true,
             const sp<IGraphicBufferAlloc>& allocator = NULL);
     virtual ~GonkBufferQueue();
     // Query native window attributes.  The "what" values are enumerated in
     // window.h (e.g. NATIVE_WINDOW_FORMAT).
     virtual int query(int what, int* value);
     // setBufferCount updates the number of available buffer slots.  If this
     // method succeeds, buffer slots will be both unallocated and owned by
     // the GonkBufferQueue object (i.e. they are not owned by the producer or
     // consumer).
     //
     // This will fail if the producer has dequeued any buffers, or if
     // bufferCount is invalid.  bufferCount must generally be a value
     // between the minimum undequeued buffer count and NUM_BUFFER_SLOTS
     // (inclusive).  It may also be set to zero (the default) to indicate
     // that the producer does not wish to set a value.  The minimum value
     // can be obtained by calling query(NATIVE_WINDOW_MIN_UNDEQUEUED_BUFFERS,
     // ...).
     //
     // This may only be called by the producer.  The consumer will be told
     // to discard buffers through the onBuffersReleased callback.
     virtual status_t setBufferCount(int bufferCount);
     // requestBuffer returns the GraphicBuffer for slot N.
     //
     // In normal operation, this is called the first time slot N is returned
     // by dequeueBuffer.  It must be called again if dequeueBuffer returns
     // flags indicating that previously-returned buffers are no longer valid.
     virtual status_t requestBuffer(int slot, sp<GraphicBuffer>* buf);
     // dequeueBuffer gets the next buffer slot index for the producer to use.
     // If a buffer slot is available then that slot index is written to the
     // location pointed to by the buf argument and a status of OK is returned.
     // If no slot is available then a status of -EBUSY is returned and buf is
     // unmodified.
     //
     // The fence parameter will be updated to hold the fence associated with
     // the buffer. The contents of the buffer must not be overwritten until the
     // fence signals. If the fence is Fence::NO_FENCE, the buffer may be
     // written immediately.
     //
     // The width and height parameters must be no greater than the minimum of
     // GL_MAX_VIEWPORT_DIMS and GL_MAX_TEXTURE_SIZE (see: glGetIntegerv).
     // An error due to invalid dimensions might not be reported until
     // updateTexImage() is called.  If width and height are both zero, the
     // default values specified by setDefaultBufferSize() are used instead.
     //
     // The pixel formats are enumerated in graphics.h, e.g.
     // HAL_PIXEL_FORMAT_RGBA_8888.  If the format is 0, the default format
     // will be used.
     //
     // The usage argument specifies gralloc buffer usage flags.  The values
     // are enumerated in gralloc.h, e.g. GRALLOC_USAGE_HW_RENDER.  These
     // will be merged with the usage flags specified by setConsumerUsageBits.
     //
     // The return value may be a negative error value or a non-negative
     // collection of flags.  If the flags are set, the return values are
     // valid, but additional actions must be performed.
     //
     // If IGraphicBufferProducer::BUFFER_NEEDS_REALLOCATION is set, the
     // producer must discard cached GraphicBuffer references for the slot
     // returned in buf.
     // If IGraphicBufferProducer::RELEASE_ALL_BUFFERS is set, the producer
     // must discard cached GraphicBuffer references for all slots.
     //
     // In both cases, the producer will need to call requestBuffer to get a
     // GraphicBuffer handle for the returned slot.
 #if ANDROID_VERSION == 17
     virtual status_t dequeueBuffer(int *buf, sp<Fence>& fence,
             uint32_t width, uint32_t height, uint32_t format, uint32_t usage) {
         return dequeueBuffer(buf, &fence, width, height, format, usage);
     }
 #endif
     virtual status_t dequeueBuffer(int *buf, sp<Fence>* fence,
             uint32_t width, uint32_t height, uint32_t format, uint32_t usage);
     // queueBuffer returns a filled buffer to the GonkBufferQueue.
     //
     // Additional data is provided in the QueueBufferInput struct.  Notably,
     // a timestamp must be provided for the buffer. The timestamp is in
     // nanoseconds, and must be monotonically increasing. Its other semantics
     // (zero point, etc) are producer-specific and should be documented by the
     // producer.
     //
     // The caller may provide a fence that signals when all rendering
     // operations have completed.  Alternatively, NO_FENCE may be used,
     // indicating that the buffer is ready immediately.
     //
     // Some values are returned in the output struct: the current settings
     // for default width and height, the current transform hint, and the
     // number of queued buffers.
     virtual status_t queueBuffer(int buf,
             const QueueBufferInput& input, QueueBufferOutput* output);
     // cancelBuffer returns a dequeued buffer to the GonkBufferQueue, but doesn't
     // queue it for use by the consumer.
     //
     // The buffer will not be overwritten until the fence signals.  The fence
     // will usually be the one obtained from dequeueBuffer.
 #if ANDROID_VERSION == 17
     virtual void cancelBuffer(int buf, sp<Fence> fence);
 #else
     virtual void cancelBuffer(int buf, const sp<Fence>& fence);
 #endif
     // setSynchronousMode sets whether dequeueBuffer is synchronous or
     // asynchronous. In synchronous mode, dequeueBuffer blocks until
     // a buffer is available, the currently bound buffer can be dequeued and
     // queued buffers will be acquired in order.  In asynchronous mode,
     // a queued buffer may be replaced by a subsequently queued buffer.
     //
     // The default mode is asynchronous.
     virtual status_t setSynchronousMode(bool enabled);
     // connect attempts to connect a producer API to the GonkBufferQueue.  This
     // must be called before any other IGraphicBufferProducer methods are
     // called except for getAllocator.  A consumer must already be connected.
     //
     // This method will fail if connect was previously called on the
     // GonkBufferQueue and no corresponding disconnect call was made (i.e. if
     // it's still connected to a producer).
     //
     // APIs are enumerated in window.h (e.g. NATIVE_WINDOW_API_CPU).
     virtual status_t connect(int api, QueueBufferOutput* output);
     // disconnect attempts to disconnect a producer API from the GonkBufferQueue.
     // Calling this method will cause any subsequent calls to other
     // IGraphicBufferProducer methods to fail except for getAllocator and connect.
     // Successfully calling connect after this will allow the other methods to
     // succeed again.
     //
     // This method will fail if the the GonkBufferQueue is not currently
     // connected to the specified producer API.
     virtual status_t disconnect(int api);
     // dump our state in a String
     virtual void dump(String8& result) const;
     virtual void dump(String8& result, const char* prefix, char* buffer, size_t SIZE) const;
     // public facing structure for BufferSlot
     struct BufferItem {
         BufferItem()
          :
            mTransform(0),
            mScalingMode(NATIVE_WINDOW_SCALING_MODE_FREEZE),
            mTimestamp(0),
            mFrameNumber(0),
            mBuf(INVALID_BUFFER_SLOT) {
              mCrop.makeInvalid();
         }
         // mGraphicBuffer points to the buffer allocated for this slot, or is NULL
         // if the buffer in this slot has been acquired in the past (see
         // BufferSlot.mAcquireCalled).
         sp<GraphicBuffer> mGraphicBuffer;
         // mCrop is the current crop rectangle for this buffer slot.
         Rect mCrop;
         // mTransform is the current transform flags for this buffer slot.
         uint32_t mTransform;
         // mScalingMode is the current scaling mode for this buffer slot.
         uint32_t mScalingMode;
         // mTimestamp is the current timestamp for this buffer slot. This gets
         // to set by queueBuffer each time this slot is queued.
         int64_t mTimestamp;
         // mFrameNumber is the number of the queued frame for this slot.
         uint64_t mFrameNumber;
         // mBuf is the slot index of this buffer
         int mBuf;
         // mFence is a fence that will signal when the buffer is idle.
         sp<Fence> mFence;
     };
     // The following public functions are the consumer-facing interface
     // acquireBuffer attempts to acquire ownership of the next pending buffer in
     // the GonkBufferQueue.  If no buffer is pending then it returns -EINVAL.  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.
     status_t acquireBuffer(BufferItem *buffer);
     // releaseBuffer releases a buffer slot from the consumer back to the
     // GonkBufferQueue.  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.
     //
     // 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.
     status_t releaseBuffer(int buf, const sp<Fence>& releaseFence);
     // consumerConnect connects a consumer to the GonkBufferQueue.  Only one
     // consumer may be connected, and when that consumer disconnects the
     // GonkBufferQueue is placed into the "abandoned" state, causing most
     // interactions with the GonkBufferQueue by the producer to fail.
     //
     // consumer may not be NULL.
     status_t consumerConnect(const sp<ConsumerListener>& consumer);
     // consumerDisconnect disconnects a consumer from the GonkBufferQueue. All
     // buffers will be freed and the GonkBufferQueue is placed in the "abandoned"
     // state, causing most interactions with the GonkBufferQueue by the producer to
     // fail.
     status_t consumerDisconnect();
     // getReleasedBuffers sets the value pointed to by slotMask to a bit mask
     // indicating which buffer slots have been released by the GonkBufferQueue
     // but have not yet been released by the consumer.
     //
     // This should be called from the onBuffersReleased() callback.
     status_t getReleasedBuffers(uint32_t* slotMask);
     // setDefaultBufferSize is used to set the size of buffers returned by
     // dequeueBuffer when a width and height of zero is requested.  Default
     // is 1x1.
     status_t setDefaultBufferSize(uint32_t w, uint32_t h);
     // 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.
     status_t setDefaultMaxBufferCount(int bufferCount);
     // 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 GonkBufferQueue.
     status_t setMaxAcquiredBufferCount(int maxAcquiredBuffers);
     // isSynchronousMode returns whether the GonkBufferQueue is currently in
     // synchronous mode.
     bool isSynchronousMode() const;
     // setConsumerName sets the name used in logging
     void setConsumerName(const String8& name);
     // setDefaultBufferFormat allows the GonkBufferQueue to create
     // GraphicBuffers of a defaultFormat if no format is specified
     // in dequeueBuffer.  Formats are enumerated in graphics.h; the
     // initial default is HAL_PIXEL_FORMAT_RGBA_8888.
     status_t setDefaultBufferFormat(uint32_t defaultFormat);
     // 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.
     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).
     status_t setTransformHint(uint32_t hint);
     mozilla::TemporaryRef<TextureClient> getTextureClientFromBuffer(ANativeWindowBuffer* buffer);
     int getSlotFromTextureClientLocked(TextureClient* client) const;
 private:
     // freeBufferLocked frees the GraphicBuffer and sync resources for the
     // given slot.
     //void freeBufferLocked(int index);
     // freeAllBuffersLocked frees the GraphicBuffer and sync resources for
     // all slots.
     //void freeAllBuffersLocked();
     void freeAllBuffersLocked();
     // setDefaultMaxBufferCountLocked sets the maximum number of buffer slots
     // that will be used if the producer does not override the buffer slot
     // count.  The count must be between 2 and NUM_BUFFER_SLOTS, inclusive.
     // The initial default is 2.
     status_t setDefaultMaxBufferCountLocked(int count);
     // getMinBufferCountLocked returns the minimum number of buffers allowed
     // given the current GonkBufferQueue state.
     int getMinMaxBufferCountLocked() const;
     // getMinUndequeuedBufferCountLocked returns the minimum number of buffers
     // that must remain in a state other than DEQUEUED.
     int getMinUndequeuedBufferCountLocked() const;
     // getMaxBufferCountLocked returns the maximum number of buffers that can
     // be allocated at once.  This value depends upon the following member
     // variables:
     //
     //      mSynchronousMode
     //      mMaxAcquiredBufferCount
     //      mDefaultMaxBufferCount
     //      mOverrideMaxBufferCount
     //
     // Any time one of these member variables is changed while a producer is
     // connected, mDequeueCondition must be broadcast.
     int getMaxBufferCountLocked() const;
     struct BufferSlot {
         BufferSlot()
         : mBufferState(BufferSlot::FREE),
           mRequestBufferCalled(false),
           mTransform(0),
           mScalingMode(NATIVE_WINDOW_SCALING_MODE_FREEZE),
           mTimestamp(0),
           mFrameNumber(0),
           mAcquireCalled(false),
           mNeedsCleanupOnRelease(false) {
             mCrop.makeInvalid();
         }
         // mGraphicBuffer points to the buffer allocated for this slot or is NULL
         // if no buffer has been allocated.
         sp<GraphicBuffer> mGraphicBuffer;
         // mTextureClient is a thin abstraction over remotely allocated GraphicBuffer.
         mozilla::RefPtr<TextureClient> mTextureClient;
         // BufferState represents the different states in which a buffer slot
         // can be.  All slots are initially FREE.
         enum BufferState {
             // FREE indicates that the buffer is available to be dequeued
             // by the producer.  The buffer may be in use by the consumer for
             // a finite time, so the buffer must not be modified until the
             // associated fence is signaled.
             //
             // The slot is "owned" by GonkBufferQueue.  It transitions to DEQUEUED
             // when dequeueBuffer is called.
             FREE = 0,
             // DEQUEUED indicates that the buffer has been dequeued by the
             // producer, but has not yet been queued or canceled.  The
             // producer may modify the buffer's contents as soon as the
             // associated ready fence is signaled.
             //
             // The slot is "owned" by the producer.  It can transition to
             // QUEUED (via queueBuffer) or back to FREE (via cancelBuffer).
             DEQUEUED = 1,
             // QUEUED indicates that the buffer has been filled by the
             // producer and queued for use by the consumer.  The buffer
             // contents may continue to be modified for a finite time, so
             // the contents must not be accessed until the associated fence
             // is signaled.
             //
             // The slot is "owned" by GonkBufferQueue.  It can transition to
             // ACQUIRED (via acquireBuffer) or to FREE (if another buffer is
             // queued in asynchronous mode).
             QUEUED = 2,
             // ACQUIRED indicates that the buffer has been acquired by the
             // consumer.  As with QUEUED, the contents must not be accessed
             // by the consumer until the fence is signaled.
             //
             // The slot is "owned" by the consumer.  It transitions to FREE
             // when releaseBuffer is called.
             ACQUIRED = 3
         };
         // mBufferState is the current state of this buffer slot.
         BufferState mBufferState;
         // mRequestBufferCalled is used for validating that the producer did
         // call requestBuffer() when told to do so. Technically this is not
         // needed but useful for debugging and catching producer bugs.
         bool mRequestBufferCalled;
         // mCrop is the current crop rectangle for this buffer slot.
         Rect mCrop;
         // mTransform is the current transform flags for this buffer slot.
         // (example: NATIVE_WINDOW_TRANSFORM_ROT_90)
         uint32_t mTransform;
         // mScalingMode is the current scaling mode for this buffer slot.
         // (example: NATIVE_WINDOW_SCALING_MODE_FREEZE)
         uint32_t mScalingMode;
         // mTimestamp is the current timestamp for this buffer slot. This gets
         // to set by queueBuffer each time this slot is queued.
         int64_t mTimestamp;
         // mFrameNumber is the number of the queued frame for this slot.  This
         // is used to dequeue buffers in LRU order (useful because buffers
         // may be released before their release fence is signaled).
         uint64_t mFrameNumber;
         // mEglFence is the EGL sync object that must signal before the buffer
         // associated with this buffer slot may be dequeued. It is initialized
         // to EGL_NO_SYNC_KHR when the buffer is created and may be set to a
         // new sync object in releaseBuffer.  (This is deprecated in favor of
         // mFence, below.)
         //EGLSyncKHR mEglFence;
         // mFence is a fence which will signal when work initiated by the
         // previous owner of the buffer is finished. When the buffer is FREE,
         // the fence indicates when the consumer has finished reading
         // from the buffer, or when the producer has finished writing if it
         // called cancelBuffer after queueing some writes. When the buffer is
         // QUEUED, it indicates when the producer has finished filling the
         // buffer. When the buffer is DEQUEUED or ACQUIRED, the fence has been
         // passed to the consumer or producer along with ownership of the
         // buffer, and mFence is set to NO_FENCE.
         sp<Fence> mFence;
         // Indicates whether this buffer has been seen by a consumer yet
         bool mAcquireCalled;
         // Indicates whether this buffer needs to be cleaned up by the
         // consumer.  This is set when a buffer in ACQUIRED state is freed.
         // It causes releaseBuffer to return STALE_BUFFER_SLOT.
         bool mNeedsCleanupOnRelease;
     };
     // mSlots is the array of buffer slots that must be mirrored on the
     // producer side. This allows buffer ownership to be transferred between
     // the producer and consumer without sending a GraphicBuffer over binder.
     // The entire array is initialized to NULL at construction time, and
     // buffers are allocated for a slot when requestBuffer is called with
     // that slot's index.
     BufferSlot mSlots[NUM_BUFFER_SLOTS];
     // mDefaultWidth holds the default width of allocated buffers. It is used
     // in dequeueBuffer() if a width and height of zero is specified.
     uint32_t mDefaultWidth;
     // mDefaultHeight holds the default height of allocated buffers. It is used
     // in dequeueBuffer() if a width and height of zero is specified.
     uint32_t mDefaultHeight;
     // mMaxAcquiredBufferCount is the number of buffers that the consumer may
     // acquire at one time.  It defaults to 1 and can be changed by the
     // consumer via the setMaxAcquiredBufferCount method, but this may only be
     // done when no producer is connected to the GonkBufferQueue.
     //
     // This value is used to derive the value returned for the
     // MIN_UNDEQUEUED_BUFFERS query by the producer.
     int mMaxAcquiredBufferCount;
     // mDefaultMaxBufferCount is the default limit on the number of buffers
     // that will be allocated at one time.  This default limit is set by the
     // consumer.  The limit (as opposed to the default limit) may be
     // overridden by the producer.
     int mDefaultMaxBufferCount;
     // mOverrideMaxBufferCount is the limit on the number of buffers that will
     // be allocated at one time. This value is set by the image producer by
     // calling setBufferCount. The default is zero, which means the producer
     // doesn't care about the number of buffers in the pool. In that case
     // mDefaultMaxBufferCount is used as the limit.
     int mOverrideMaxBufferCount;
     // mGraphicBufferAlloc is the connection to SurfaceFlinger that is used to
     // allocate new GraphicBuffer objects.
     sp<IGraphicBufferAlloc> mGraphicBufferAlloc;
     // mConsumerListener is used to notify the connected consumer of
     // asynchronous events that it may wish to react to.  It is initially set
     // to NULL and is written by consumerConnect and consumerDisconnect.
     sp<ConsumerListener> mConsumerListener;
     // mSynchronousMode whether we're in synchronous mode or not
     bool mSynchronousMode;
     // mAllowSynchronousMode whether we allow synchronous mode or not.  Set
     // when the GonkBufferQueue is created (by the consumer).
     const bool mAllowSynchronousMode;
     // mConnectedApi indicates the producer API that is currently connected
     // to this GonkBufferQueue.  It defaults to NO_CONNECTED_API (= 0), and gets
     // updated by the connect and disconnect methods.
     int mConnectedApi;
     // mDequeueCondition condition used for dequeueBuffer in synchronous mode
     mutable Condition mDequeueCondition;
     // mQueue is a FIFO of queued buffers used in synchronous mode
     typedef Vector<int> Fifo;
     Fifo mQueue;
     // mAbandoned indicates that the GonkBufferQueue will no longer be used to
     // consume image buffers pushed to it using the IGraphicBufferProducer
     // interface.  It is initialized to false, and set to true in the
     // consumerDisconnect method.  A GonkBufferQueue that has been abandoned will
     // return the NO_INIT error from all IGraphicBufferProducer methods
     // capable of returning an error.
     bool mAbandoned;
     // mConsumerName is a string used to identify the GonkBufferQueue in log
     // messages.  It is set by the setConsumerName method.
     String8 mConsumerName;
     // mMutex is the mutex used to prevent concurrent access to the member
     // variables of GonkBufferQueue objects. It must be locked whenever the
     // member variables are accessed.
     mutable Mutex mMutex;
     // mFrameCounter is the free running counter, incremented on every
     // successful queueBuffer call.
     uint64_t mFrameCounter;
     // mBufferHasBeenQueued is true once a buffer has been queued.  It is
     // reset when something causes all buffers to be freed (e.g. changing the
     // buffer count).
     bool mBufferHasBeenQueued;
     // mDefaultBufferFormat can be set so it will override
     // the buffer format when it isn't specified in dequeueBuffer
     uint32_t mDefaultBufferFormat;
     // mConsumerUsageBits contains flags the consumer wants for GraphicBuffers
     uint32_t mConsumerUsageBits;
     // mTransformHint is used to optimize for screen rotations
     uint32_t mTransformHint;
 };
 // ----------------------------------------------------------------------------
 }; // namespace android
 #endif // ANDROID_GUI_BUFFERQUEUE_H

The Tor Browser / annotate

widget/gonk/nativewindow/GonkBufferQueueJB.h@6474c204b198 (annotated)

widget/gonk/nativewindow/GonkBufferQueueJB.h