Refactored ISurfaceTexture calls from SurfaceTexture into BufferQueue.
Change-Id: I514f6b802f6b49c9ae27bed37bf0b9d23da03c9a
diff --git a/include/gui/BufferQueue.h b/include/gui/BufferQueue.h
new file mode 100644
index 0000000..991a181
--- /dev/null
+++ b/include/gui/BufferQueue.h
@@ -0,0 +1,343 @@
+/*
+ * 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 <EGL/egl.h>
+
+#include <gui/ISurfaceTexture.h>
+
+#include <surfaceflinger/IGraphicBufferAlloc.h>
+#include <ui/GraphicBuffer.h>
+
+#include <utils/String8.h>
+#include <utils/Vector.h>
+#include <utils/threads.h>
+
+namespace android {
+// ----------------------------------------------------------------------------
+
+class BufferQueue : public BnSurfaceTexture {
+public:
+ enum { MIN_UNDEQUEUED_BUFFERS = 2 };
+ enum {
+ MIN_ASYNC_BUFFER_SLOTS = MIN_UNDEQUEUED_BUFFERS + 1,
+ MIN_SYNC_BUFFER_SLOTS = MIN_UNDEQUEUED_BUFFERS
+ };
+ enum { NUM_BUFFER_SLOTS = 32 };
+ enum { NO_CONNECTED_API = 0 };
+
+ struct FrameAvailableListener : 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;
+ };
+
+ // BufferQueue manages a pool of gralloc memory slots to be used
+ // by producers and consumers.
+ // allowSynchronousMode specifies whether or not synchronous mode can be
+ // enabled.
+ BufferQueue(bool allowSynchronousMode = true);
+ virtual ~BufferQueue();
+
+ // setBufferCount updates the number of available buffer slots. After
+ // calling this all buffer slots are both unallocated and owned by the
+ // BufferQueue object (i.e. they are not owned by the client).
+ virtual status_t setBufferCount(int bufferCount);
+
+ virtual status_t requestBuffer(int slot, sp<GraphicBuffer>* buf);
+
+ // dequeueBuffer gets the next buffer slot index for the client 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 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.
+ virtual status_t dequeueBuffer(int *buf, uint32_t width, uint32_t height,
+ uint32_t format, uint32_t usage);
+
+ // queueBuffer returns a filled buffer to the BufferQueue. In addition, 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 client-dependent and should be documented by the
+ // client.
+ virtual status_t queueBuffer(int buf, int64_t timestamp,
+ uint32_t* outWidth, uint32_t* outHeight, uint32_t* outTransform);
+ virtual void cancelBuffer(int buf);
+ virtual status_t setCrop(const Rect& reg);
+ virtual status_t setTransform(uint32_t transform);
+ virtual status_t setScalingMode(int mode);
+
+ // setSynchronousMode set 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 retired in order.
+ // The default mode is asynchronous.
+ virtual status_t setSynchronousMode(bool enabled);
+
+ // connect attempts to connect a producer client API to the BufferQueue.
+ // This must be called before any other ISurfaceTexture methods are called
+ // except for getAllocator.
+ //
+ // This method will fail if the connect was previously called on the
+ // BufferQueue and no corresponding disconnect call was made.
+ virtual status_t connect(int api,
+ uint32_t* outWidth, uint32_t* outHeight, uint32_t* outTransform);
+
+ // disconnect attempts to disconnect a producer client API from the
+ // BufferQueue. Calling this method will cause any subsequent calls to other
+ // ISurfaceTexture 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 BufferQueue is not currently
+ // connected to the specified client API.
+ virtual status_t disconnect(int api);
+
+protected:
+
+ // freeBufferLocked frees the resources (both GraphicBuffer and EGLImage)
+ // for the given slot.
+ void freeBufferLocked(int index);
+
+ // freeAllBuffersLocked frees the resources (both GraphicBuffer and
+ // EGLImage) for all slots.
+ void freeAllBuffersLocked();
+
+ // freeAllBuffersExceptHeadLocked frees the resources (both GraphicBuffer
+ // and EGLImage) for all slots except the head of mQueue
+ void freeAllBuffersExceptHeadLocked();
+
+ // drainQueueLocked drains the buffer queue if we're in synchronous mode
+ // returns immediately otherwise. It returns NO_INIT if the BufferQueue
+ // became abandoned or disconnected during this call.
+ status_t drainQueueLocked();
+
+ // drainQueueAndFreeBuffersLocked drains the buffer queue if we're in
+ // synchronous mode and free all buffers. In asynchronous mode, all buffers
+ // are freed except the current buffer.
+ status_t drainQueueAndFreeBuffersLocked();
+
+ status_t setBufferCountServerLocked(int bufferCount);
+
+ enum { INVALID_BUFFER_SLOT = -1 };
+
+ struct BufferSlot {
+
+ BufferSlot()
+ : mEglImage(EGL_NO_IMAGE_KHR),
+ mEglDisplay(EGL_NO_DISPLAY),
+ mBufferState(BufferSlot::FREE),
+ mRequestBufferCalled(false),
+ mTransform(0),
+ mScalingMode(NATIVE_WINDOW_SCALING_MODE_FREEZE),
+ mTimestamp(0),
+ mFrameNumber(0),
+ mFence(EGL_NO_SYNC_KHR) {
+ mCrop.makeInvalid();
+ }
+
+ // mGraphicBuffer points to the buffer allocated for this slot or is NULL
+ // if no buffer has been allocated.
+ sp<GraphicBuffer> mGraphicBuffer;
+
+ // mEglImage is the EGLImage created from mGraphicBuffer.
+ EGLImageKHR mEglImage;
+
+ // mEglDisplay is the EGLDisplay used to create mEglImage.
+ EGLDisplay mEglDisplay;
+
+ // BufferState represents the different states in which a buffer slot
+ // can be.
+ enum BufferState {
+ // FREE indicates that the buffer is not currently being used and
+ // will not be used in the future until it gets dequeued and
+ // subsequently queued by the client.
+ FREE = 0,
+
+ // DEQUEUED indicates that the buffer has been dequeued by the
+ // client, but has not yet been queued or canceled. The buffer is
+ // considered 'owned' by the client, and the server should not use
+ // it for anything.
+ //
+ // Note that when in synchronous-mode (mSynchronousMode == true),
+ // the buffer that's currently attached to the texture may be
+ // dequeued by the client. That means that the current buffer can
+ // be in either the DEQUEUED or QUEUED state. In asynchronous mode,
+ // however, the current buffer is always in the QUEUED state.
+ DEQUEUED = 1,
+
+ // QUEUED indicates that the buffer has been queued by the client,
+ // and has not since been made available for the client to dequeue.
+ // Attaching the buffer to the texture does NOT transition the
+ // buffer away from the QUEUED state. However, in Synchronous mode
+ // the current buffer may be dequeued by the client under some
+ // circumstances. See the note about the current buffer in the
+ // documentation for DEQUEUED.
+ QUEUED = 2,
+ };
+
+ // mBufferState is the current state of this buffer slot.
+ BufferState mBufferState;
+
+ // mRequestBufferCalled is used for validating that the client did
+ // call requestBuffer() when told to do so. Technically this is not
+ // needed but useful for debugging and catching client bugs.
+ bool mRequestBufferCalled;
+
+ // mCrop is the current crop rectangle for this buffer slot. This gets
+ // set to mNextCrop each time queueBuffer gets called for this buffer.
+ Rect mCrop;
+
+ // mTransform is the current transform flags for this buffer slot. This
+ // gets set to mNextTransform each time queueBuffer gets called for this
+ // slot.
+ uint32_t mTransform;
+
+ // mScalingMode is the current scaling mode for this buffer slot. This
+ // gets set to mNextScalingMode each time queueBuffer gets called for
+ // this 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;
+
+ // mFence 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 (optionally, based
+ // on a compile-time option) set to a new sync object in updateTexImage.
+ EGLSyncKHR mFence;
+ };
+
+ // mSlots is the array of buffer slots that must be mirrored on the client
+ // side. This allows buffer ownership to be transferred between the client
+ // and server 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 requestBuffers() if a width and height of zero is specified.
+ uint32_t mDefaultWidth;
+
+ // mDefaultHeight holds the default height of allocated buffers. It is used
+ // in requestBuffers() if a width and height of zero is specified.
+ uint32_t mDefaultHeight;
+
+ // mPixelFormat holds the pixel format of allocated buffers. It is used
+ // in requestBuffers() if a format of zero is specified.
+ uint32_t mPixelFormat;
+
+ // mBufferCount is the number of buffer slots that the client and server
+ // must maintain. It defaults to MIN_ASYNC_BUFFER_SLOTS and can be changed
+ // by calling setBufferCount or setBufferCountServer
+ int mBufferCount;
+
+ // mClientBufferCount is the number of buffer slots requested by the client.
+ // The default is zero, which means the client doesn't care how many buffers
+ // there is.
+ int mClientBufferCount;
+
+ // mServerBufferCount buffer count requested by the server-side
+ int mServerBufferCount;
+
+ // mCurrentTexture is the buffer slot index of the buffer that is currently
+ // bound to the OpenGL texture. It is initialized to INVALID_BUFFER_SLOT,
+ // indicating that no buffer slot is currently bound to the texture. Note,
+ // however, that a value of INVALID_BUFFER_SLOT does not necessarily mean
+ // that no buffer is bound to the texture. A call to setBufferCount will
+ // reset mCurrentTexture to INVALID_BUFFER_SLOT.
+ int mCurrentTexture;
+
+ // mNextCrop is the crop rectangle that will be used for the next buffer
+ // that gets queued. It is set by calling setCrop.
+ Rect mNextCrop;
+
+ // mNextTransform is the transform identifier that will be used for the next
+ // buffer that gets queued. It is set by calling setTransform.
+ uint32_t mNextTransform;
+
+ // mNextScalingMode is the scaling mode that will be used for the next
+ // buffers that get queued. It is set by calling setScalingMode.
+ int mNextScalingMode;
+
+ // mGraphicBufferAlloc is the connection to SurfaceFlinger that is used to
+ // allocate new GraphicBuffer objects.
+ sp<IGraphicBufferAlloc> mGraphicBufferAlloc;
+
+ // mFrameAvailableListener is the listener object that will be called when a
+ // new frame becomes available. If it is not NULL it will be called from
+ // queueBuffer.
+ sp<FrameAvailableListener> mFrameAvailableListener;
+
+ // mSynchronousMode whether we're in synchronous mode or not
+ bool mSynchronousMode;
+
+ // mAllowSynchronousMode whether we allow synchronous mode or not
+ const bool mAllowSynchronousMode;
+
+ // mConnectedApi indicates the API that is currently connected to this
+ // BufferQueue. 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 BufferQueue will no longer be used to
+ // consume images buffers pushed to it using the ISurfaceTexture interface.
+ // It is initialized to false, and set to true in the abandon method. A
+ // BufferQueue that has been abandoned will return the NO_INIT error from
+ // all ISurfaceTexture methods capable of returning an error.
+ bool mAbandoned;
+
+ // mName is a string used to identify the BufferQueue in log messages.
+ // It is set by the setName method.
+ String8 mName;
+
+ // mMutex is the mutex used to prevent concurrent access to the member
+ // variables of BufferQueue objects. It must be locked whenever the
+ // member variables are accessed.
+ mutable Mutex mMutex;
+
+ // mFrameCounter is the free running counter, incremented for every buffer queued
+ // with the surface Texture.
+ uint64_t mFrameCounter;
+};
+
+// ----------------------------------------------------------------------------
+}; // namespace android
+
+#endif // ANDROID_GUI_BUFFERQUEUE_H