gfx/thebes/gfxReusableSharedImageSurfaceWrapper.h

   1 /* This Source Code Form is subject to the terms of the Mozilla Public
   2  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
   3  * You can obtain one at http://mozilla.org/MPL/2.0/. */
   4
   5 #ifndef GFXSHMCOWSURFACEWRAPPER
   6 #define GFXSHMCOWSURFACEWRAPPER
   7
   8 #include "gfxReusableSurfaceWrapper.h"
   9 #include "mozilla/RefPtr.h"
  10
  11 class gfxSharedImageSurface;
  12
  13 namespace mozilla {
  14 namespace ipc {
  15 class Shmem;
  16 }
  17 namespace layers {
  18 class ISurfaceAllocator;
  19 }
  20 }
  21
  22 /**
  23  * A cross-process capable implementation of gfxReusableSurfaceWrapper based
  24  * on gfxSharedImageSurface.
  25  */
  26 class gfxReusableSharedImageSurfaceWrapper : public gfxReusableSurfaceWrapper {
  27 public:
  28   gfxReusableSharedImageSurfaceWrapper(mozilla::layers::ISurfaceAllocator* aAllocator,
  29                                        gfxSharedImageSurface* aSurface);
  30 protected:
  31   ~gfxReusableSharedImageSurfaceWrapper();
  32
  33 public:
  34   const unsigned char* GetReadOnlyData() const MOZ_OVERRIDE;
  35   gfxImageFormat Format() MOZ_OVERRIDE;
  36   gfxReusableSurfaceWrapper* GetWritable(gfxImageSurface** aSurface) MOZ_OVERRIDE;
  37   void ReadLock() MOZ_OVERRIDE;
  38   void ReadUnlock() MOZ_OVERRIDE;
  39
  40   Type GetType()
  41   {
  42     return TYPE_SHARED_IMAGE;
  43   }
  44
  45   /**
  46    * Returns the shared memory segment that backs the shared image surface.
  47    */
  48   mozilla::ipc::Shmem& GetShmem();
  49
  50   /**
  51    * Create a gfxReusableSurfaceWrapper from the shared memory segment of a
  52    * gfxSharedImageSurface. A ReadLock must be held, which will be adopted by
  53    * the returned gfxReusableSurfaceWrapper.
  54    */
  55   static already_AddRefed<gfxReusableSharedImageSurfaceWrapper>
  56   Open(mozilla::layers::ISurfaceAllocator* aAllocator, const mozilla::ipc::Shmem& aShmem);
  57
  58 private:
  59   mozilla::RefPtr<mozilla::layers::ISurfaceAllocator> mAllocator;
  60   nsRefPtr<gfxSharedImageSurface>         mSurface;
  61 };
  62
  63 #endif // GFXSHMCOWSURFACEWRAPPER