Merge "SurfaceTexture: inherit from ConsumerBase (try 2)" into jb-mr1-dev

2 files changed, 69 insertions, 123 deletions

diff --git a/include/gui/ConsumerBase.h b/include/gui/ConsumerBase.h
index d2bf0f6..a0ddca8 100644
--- a/include/gui/ConsumerBase.h
+++ b/include/gui/ConsumerBase.h
@@ -86,42 +86,25 @@ private:
 
 protected:
 
-    // TODO: Fix this comment
-    // ConsumerBase constructs a new ConsumerBase object. tex indicates the
-    // name of the OpenGL ES texture to which images are to be streamed.
-    // allowSynchronousMode specifies whether or not synchronous mode can be
-    // enabled. texTarget specifies the OpenGL ES texture target to which the
-    // texture will be bound in updateTexImage. useFenceSync specifies whether
-    // fences should be used to synchronize access to buffers if that behavior
-    // is enabled at compile-time. A custom bufferQueue can be specified
-    // if behavior for queue/dequeue/connect etc needs to be customized.
-    // Otherwise a default BufferQueue will be created and used.
-    //
-    // For legacy reasons, the ConsumerBase is created in a state where it is
-    // considered attached to an OpenGL ES context for the purposes of the
-    // attachToContext and detachFromContext methods. However, despite being
-    // considered "attached" to a context, the specific OpenGL ES context
-    // doesn't get latched until the first call to updateTexImage. After that
-    // point, all calls to updateTexImage must be made with the same OpenGL ES
-    // context current.
-    //
-    // A ConsumerBase may be detached from one OpenGL ES context and then
-    // attached to a different context using the detachFromContext and
-    // attachToContext methods, respectively. The intention of these methods is
-    // purely to allow a ConsumerBase to be transferred from one consumer
-    // context to another. If such a transfer is not needed there is no
-    // requirement that either of these methods be called.
+    // ConsumerBase constructs a new ConsumerBase object to consume image
+    // buffers from the given BufferQueue.
     ConsumerBase(const sp<BufferQueue> &bufferQueue);
 
     // Implementation of the BufferQueue::ConsumerListener interface.  These
     // calls are used to notify the ConsumerBase of asynchronous events in the
-    // BufferQueue.
+    // BufferQueue.  These methods should not need to be overridden by derived
+    // classes, but if they are overridden the ConsumerBase implementation
+    // must be called from the derived class.
     virtual void onFrameAvailable();
     virtual void onBuffersReleased();
 
     // freeBufferLocked frees up the given buffer slot.  If the slot has been
     // initialized this will release the reference to the GraphicBuffer in that
-    // slot and destroy the EGLImage in that slot.  Otherwise it has no effect.
+    // slot.  Otherwise it has no effect.
+    //
+    // Derived classes should override this method to clean up any state they
+    // keep per slot.  If it is overridden, the derived class's implementation
+    // must call ConsumerBase::freeBufferLocked.
     //
     // This method must be called with mMutex locked.
     virtual void freeBufferLocked(int slotIndex);
@@ -131,18 +114,43 @@ protected:
     // abandon method should be overridden by child classes to add abandon-
     // time behavior.
     //
+    // Derived classes should override this method to clean up any object
+    // state they keep (as opposed to per-slot state).  If it is overridden,
+    // the derived class's implementation must call ConsumerBase::abandonLocked.
+    //
     // This method must be called with mMutex locked.
     virtual void abandonLocked();
 
+    // dumpLocked dumps the current state of the ConsumerBase object to the
+    // result string.  Each line is prefixed with the string pointed to by the
+    // prefix argument.  The buffer argument points to a buffer that may be
+    // used for intermediate formatting data, and the size of that buffer is
+    // indicated by the size argument.
+    //
+    // Derived classes should override this method to dump their internal
+    // state.  If this method is overridden the derived class's implementation
+    // should call ConsumerBase::dumpLocked.
+    //
+    // This method must be called with mMutex locked.
     virtual void dumpLocked(String8& result, const char* prefix, char* buffer,
-            size_t SIZE) const;
+            size_t size) const;
 
     // acquireBufferLocked fetches the next buffer from the BufferQueue and
     // updates the buffer slot for the buffer returned.
+    //
+    // Derived classes should override this method to perform any
+    // initialization that must take place the first time a buffer is assigned
+    // to a slot.  If it is overridden the derived class's implementation must
+    // call ConsumerBase::acquireBufferLocked.
     virtual status_t acquireBufferLocked(BufferQueue::BufferItem *item);
 
     // releaseBufferLocked relinquishes control over a buffer, returning that
     // control to the BufferQueue.
+    //
+    // Derived classes should override this method to perform any cleanup that
+    // must take place when a buffer is released back to the BufferQueue.  If
+    // it is overridden the derived class's implementation must call
+    // ConsumerBase::acquireBufferLocked.
     virtual status_t releaseBufferLocked(int buf, EGLDisplay display,
            EGLSyncKHR eglFence, const sp<Fence>& fence);
 
@@ -189,17 +197,12 @@ protected:
     // if none is supplied
     sp<BufferQueue> mBufferQueue;
 
-    // mAttached indicates whether the ConsumerBase is currently attached to
-    // an OpenGL ES context.  For legacy reasons, this is initialized to true,
-    // indicating that the ConsumerBase is considered to be attached to
-    // whatever context is current at the time of the first updateTexImage call.
-    // It is set to false by detachFromContext, and then set to true again by
-    // attachToContext.
-    bool mAttached;
-
     // mMutex is the mutex used to prevent concurrent access to the member
     // variables of ConsumerBase objects. It must be locked whenever the
-    // member variables are accessed.
+    // member variables are accessed or when any of the *Locked methods are
+    // called.
+    //
+    // This mutex is intended to be locked by derived classes.
     mutable Mutex mMutex;
 };
 
diff --git a/include/gui/SurfaceTexture.h b/include/gui/SurfaceTexture.h
index 66c390a..98741c5 100644
--- a/include/gui/SurfaceTexture.h
+++ b/include/gui/SurfaceTexture.h
@@ -24,6 +24,7 @@
 
 #include <gui/ISurfaceTexture.h>
 #include <gui/BufferQueue.h>
+#include <gui/ConsumerBase.h>
 
 #include <ui/GraphicBuffer.h>
 
@@ -39,20 +40,9 @@ namespace android {
 
 class String8;
 
-class SurfaceTexture : public virtual RefBase,
-        protected BufferQueue::ConsumerListener {
+class SurfaceTexture : public ConsumerBase {
 public:
-    struct FrameAvailableListener : public virtual RefBase {
-        // onFrameAvailable() is called 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;
-    };
+    typedef ConsumerBase::FrameAvailableListener FrameAvailableListener;
 
     // SurfaceTexture constructs a new SurfaceTexture object. tex indicates the
     // name of the OpenGL ES texture to which images are to be streamed.
@@ -82,8 +72,6 @@ public:
             GLenum texTarget = GL_TEXTURE_EXTERNAL_OES, bool useFenceSync = true,
             const sp<BufferQueue> &bufferQueue = 0);
 
-    virtual ~SurfaceTexture();
-
     // updateTexImage sets the image contents of the target texture to that of
     // the most recently queued buffer.
     //
@@ -132,16 +120,6 @@ public:
     // documented by the source.
     int64_t getTimestamp();
 
-    // setFrameAvailableListener sets the listener object that will be notified
-    // when a new frame becomes available.
-    void setFrameAvailableListener(const sp<FrameAvailableListener>& listener);
-
-    // getAllocator retrieves the binder object that must be referenced as long
-    // as the GraphicBuffers dequeued from this SurfaceTexture are referenced.
-    // Holding this binder reference prevents SurfaceFlinger from freeing the
-    // buffers before the client is done with them.
-    sp<IBinder> getAllocator();
-
     // setDefaultBufferSize is used to set the size of buffers returned by
     // requestBuffers when a with and height of zero is requested.
     // A call to setDefaultBufferSize() may trigger requestBuffers() to
@@ -180,17 +158,6 @@ public:
     // synchronous mode.
     bool isSynchronousMode() const;
 
-    // abandon frees all the buffers and puts the SurfaceTexture into the
-    // 'abandoned' state.  Once put in this state the SurfaceTexture can never
-    // leave it.  When in the 'abandoned' state, all methods of the
-    // ISurfaceTexture interface will fail with the NO_INIT error.
-    //
-    // Note that while calling this method causes all the buffers to be freed
-    // from the perspective of the the SurfaceTexture, if there are additional
-    // references on the buffers (e.g. if a buffer is referenced by a client or
-    // by OpenGL ES as a texture) then those buffer will remain allocated.
-    void abandon();
-
     // set the name of the SurfaceTexture that will be used to identify it in
     // log messages.
     void setName(const String8& name);
@@ -204,7 +171,9 @@ public:
 
     // getBufferQueue returns the BufferQueue object to which this
     // SurfaceTexture is connected.
-    sp<BufferQueue> getBufferQueue() const;
+    sp<BufferQueue> getBufferQueue() const {
+        return mBufferQueue;
+    }
 
     // detachFromContext detaches the SurfaceTexture from the calling thread's
     // current OpenGL ES context.  This context must be the same as the context
@@ -233,17 +202,25 @@ public:
     // current at the time of the last call to detachFromContext.
     status_t attachToContext(GLuint tex);
 
-    // 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;
-
 protected:
 
-    // Implementation of the BufferQueue::ConsumerListener interface.  These
-    // calls are used to notify the SurfaceTexture of asynchronous events in the
-    // BufferQueue.
-    virtual void onFrameAvailable();
-    virtual void onBuffersReleased();
+    // abandonLocked overrides the ConsumerBase method to clear
+    // mCurrentTextureBuf in addition to the ConsumerBase behavior.
+    virtual void abandonLocked();
+
+    // dumpLocked overrides the ConsumerBase method to dump SurfaceTexture-
+    // specific info in addition to the ConsumerBase behavior.
+    virtual void dumpLocked(String8& result, const char* prefix, char* buffer,
+           size_t size) const;
+
+    // acquireBufferLocked overrides the ConsumerBase method to update the
+    // mEglSlots array in addition to the ConsumerBase behavior.
+    virtual status_t acquireBufferLocked(BufferQueue::BufferItem *item);
+
+    // releaseBufferLocked overrides the ConsumerBase method to update the
+    // mEglSlots array in addition to the ConsumerBase.
+    virtual status_t releaseBufferLocked(int buf, EGLDisplay display,
+           EGLSyncKHR eglFence, const sp<Fence>& fence);
 
     static bool isExternalFormat(uint32_t format);
 
@@ -271,7 +248,7 @@ private:
     // slot and destroy the EGLImage in that slot.  Otherwise it has no effect.
     //
     // This method must be called with mMutex locked.
-    void freeBufferLocked(int slotIndex);
+    virtual void freeBufferLocked(int slotIndex);
 
     // computeCurrentTransformMatrix computes the transform matrix for the
     // current texture.  It uses mCurrentTransform and the current GraphicBuffer
@@ -351,11 +328,9 @@ private:
     struct EGLSlot {
         EGLSlot()
         : mEglImage(EGL_NO_IMAGE_KHR),
-          mFence(EGL_NO_SYNC_KHR) {
+          mEglFence(EGL_NO_SYNC_KHR) {
         }
 
-        sp<GraphicBuffer> mGraphicBuffer;
-
         // mEglImage is the EGLImage created from mGraphicBuffer.
         EGLImageKHR mEglImage;
 
@@ -363,14 +338,7 @@ private:
         // 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;
-
-        // mReleaseFence is a fence which will signal when the buffer
-        // associated with this buffer slot is no longer being used by the
-        // consumer and can be overwritten. The buffer can be dequeued before
-        // the fence signals; the producer is responsible for delaying writes
-        // until it signals.
-        sp<Fence> mReleaseFence;
+        EGLSyncKHR mEglFence;
     };
 
     // mEglDisplay is the EGLDisplay with which this SurfaceTexture is currently
@@ -392,23 +360,7 @@ private:
     // slot that has not yet been used. The buffer allocated to a slot will also
     // be replaced if the requested buffer usage or geometry differs from that
     // of the buffer allocated to a slot.
-    EGLSlot mEGLSlots[BufferQueue::NUM_BUFFER_SLOTS];
-
-    // 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 SurfaceTexture in log messages.
-    // It can be set by the setName method.
-    String8 mName;
-
-    // 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;
+    EGLSlot mEglSlots[BufferQueue::NUM_BUFFER_SLOTS];
 
     // mCurrentTexture is the buffer slot index of the buffer that is currently
     // bound to the OpenGL texture. It is initialized to INVALID_BUFFER_SLOT,
@@ -418,22 +370,13 @@ private:
     // reset mCurrentTexture to INVALID_BUFFER_SLOT.
     int mCurrentTexture;
 
-    // The SurfaceTexture has-a BufferQueue and is responsible for creating this object
-    // if none is supplied
-    sp<BufferQueue> mBufferQueue;
-
-    // mAttached indicates whether the SurfaceTexture is currently attached to
+    // mAttached indicates whether the ConsumerBase is currently attached to
     // an OpenGL ES context.  For legacy reasons, this is initialized to true,
-    // indicating that the SurfaceTexture is considered to be attached to
+    // indicating that the ConsumerBase is considered to be attached to
     // whatever context is current at the time of the first updateTexImage call.
     // It is set to false by detachFromContext, and then set to true again by
     // attachToContext.
     bool mAttached;
-
-    // mMutex is the mutex used to prevent concurrent access to the member
-    // variables of SurfaceTexture objects. It must be locked whenever the
-    // member variables are accessed.
-    mutable Mutex mMutex;
 };
 
 // ----------------------------------------------------------------------------