Add multi-process GpuMemoryBuffer framework.

content/common/gpu/client/gpu_memory_buffer_impl.h

+// Copyright (c) 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CONTENT_COMMON_GPU_CLIENT_GPU_MEMORY_BUFFER_IMPL_H_
+#define CONTENT_COMMON_GPU_CLIENT_GPU_MEMORY_BUFFER_IMPL_H_
+
+#include "base/memory/scoped_ptr.h"
+#include "ui/gfx/gpu_memory_buffer.h"
+#include "ui/gfx/size.h"
+
+namespace content {
+
+// Provides common implementation of a GPU memory buffer based
+// on a shared memory handle.
+class GpuMemoryBufferImpl : public gfx::GpuMemoryBuffer {
+ public:
+  GpuMemoryBufferImpl(scoped_ptr<base::SharedMemory> shared_memory,
+                      size_t width,
+                      size_t height,
+                      unsigned internalformat);
+  virtual ~GpuMemoryBufferImpl();
+
+  // Overridden from gfx::GpuMemoryBuffer:
+  virtual void Map(AccessMode mode, void** vaddr) OVERRIDE;
+  virtual void Unmap() OVERRIDE;
+  virtual bool IsMapped() const OVERRIDE;
+  virtual uint32 GetStride() const OVERRIDE;
+  virtual gfx::GpuMemoryBufferHandle GetHandle() const OVERRIDE;
+
+  static bool IsFormatValid(unsigned internalformat);
+  static size_t BytesPerPixel(unsigned internalformat);
+
+ private:
+  scoped_ptr<base::SharedMemory> shared_memory_;
+  const gfx::Size size_;
+  unsigned internalformat_;
+  bool mapped_;
+
+  DISALLOW_COPY_AND_ASSIGN(GpuMemoryBufferImpl);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_COMMON_GPU_CLIENT_GPU_MEMORY_BUFFER_IMPL_H_