Fix remote GraphicBuffer allocation in SurfaceFlinger.

This change fixes a horrible hack that I did to allow application
processes to create GraphicBuffer objects by making a binder call to
SurfaceFlinger.  This change introduces a new binder interface
specifically for doing this, and does it in such a way that
SurfaceFlinger will maintain a reference to the buffers until the app is
done with them.

Change-Id: Icb240397c6c206d7f69124c1497a829f051cb49b
diff --git a/include/surfaceflinger/IGraphicBufferAlloc.h b/include/surfaceflinger/IGraphicBufferAlloc.h
new file mode 100644
index 0000000..d996af7
--- /dev/null
+++ b/include/surfaceflinger/IGraphicBufferAlloc.h
@@ -0,0 +1,64 @@
+/*
+ * Copyright (C) 2011 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_SF_IGRAPHIC_BUFFER_ALLOC_H
+#define ANDROID_SF_IGRAPHIC_BUFFER_ALLOC_H
+
+#include <stdint.h>
+#include <sys/types.h>
+
+#include <utils/RefBase.h>
+
+#include <binder/IInterface.h>
+
+namespace android {
+// ----------------------------------------------------------------------------
+
+class IGraphicBufferAlloc : public IInterface
+{
+public:
+    DECLARE_META_INTERFACE(GraphicBufferAlloc);
+
+    /* Create a new GraphicBuffer for the client to use.  The server will
+     * maintain a reference to the newly created GraphicBuffer until
+     * freeAllGraphicBuffers is called.
+     */
+    virtual sp<GraphicBuffer> createGraphicBuffer(uint32_t w, uint32_t h,
+            PixelFormat format, uint32_t usage) = 0;
+
+    /* Free all but one of the GraphicBuffer objects that the server is
+     * currently referencing. If bufIndex is not a valid index of the buffers
+     * the server is referencing, then all buffers are freed.
+     */
+    virtual void freeAllGraphicBuffersExcept(int bufIndex) = 0;
+};
+
+// ----------------------------------------------------------------------------
+
+class BnGraphicBufferAlloc : public BnInterface<IGraphicBufferAlloc>
+{
+public:
+    virtual status_t    onTransact( uint32_t code,
+                                    const Parcel& data,
+                                    Parcel* reply,
+                                    uint32_t flags = 0);
+};
+
+// ----------------------------------------------------------------------------
+
+}; // namespace android
+
+#endif // ANDROID_SF_IGRAPHIC_BUFFER_ALLOC_H