content/renderer/pepper/ppb_buffer_impl.h

   1 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CONTENT_RENDERER_PEPPER_PPB_BUFFER_IMPL_H_
   6 #define CONTENT_RENDERER_PEPPER_PPB_BUFFER_IMPL_H_
   7
   8 #include "base/basictypes.h"
   9 #include "base/memory/ref_counted.h"
  10 #include "base/memory/scoped_ptr.h"
  11 #include "base/memory/shared_memory.h"
  12 #include "ppapi/shared_impl/resource.h"
  13 #include "ppapi/thunk/ppb_buffer_api.h"
  14
  15 namespace content {
  16
  17 class PPB_Buffer_Impl : public ppapi::Resource,
  18                         public ppapi::thunk::PPB_Buffer_API {
  19  public:
  20   static PP_Resource Create(PP_Instance instance, uint32_t size);
  21   static scoped_refptr<PPB_Buffer_Impl> CreateResource(PP_Instance instance,
  22                                                        uint32_t size);
  23
  24   virtual PPB_Buffer_Impl* AsPPB_Buffer_Impl();
  25
  26   base::SharedMemory* shared_memory() const { return shared_memory_.get(); }
  27   uint32_t size() const { return size_; }
  28
  29   // Resource overrides.
  30   ppapi::thunk::PPB_Buffer_API* AsPPB_Buffer_API() override;
  31
  32   // PPB_Buffer_API implementation.
  33   PP_Bool Describe(uint32_t* size_in_bytes) override;
  34   PP_Bool IsMapped() override;
  35   void* Map() override;
  36   void Unmap() override;
  37
  38   // Trusted.
  39   int32_t GetSharedMemory(base::SharedMemory** shm) override;
  40
  41  private:
  42   ~PPB_Buffer_Impl() override;
  43
  44   explicit PPB_Buffer_Impl(PP_Instance instance);
  45   bool Init(uint32_t size);
  46
  47   scoped_ptr<base::SharedMemory> shared_memory_;
  48   uint32_t size_;
  49   int map_count_;
  50
  51   DISALLOW_COPY_AND_ASSIGN(PPB_Buffer_Impl);
  52 };
  53
  54 // Ensures that the given buffer is mapped, and returns it to its previous
  55 // mapped state in the destructor.
  56 class BufferAutoMapper {
  57  public:
  58   explicit BufferAutoMapper(ppapi::thunk::PPB_Buffer_API* api);
  59   ~BufferAutoMapper();
  60
  61   // Will be NULL on failure to map.
  62   void* data() { return data_; }
  63   uint32_t size() { return size_; }
  64
  65  private:
  66   ppapi::thunk::PPB_Buffer_API* api_;
  67
  68   bool needs_unmap_;
  69
  70   void* data_;
  71   uint32_t size_;
  72
  73   DISALLOW_COPY_AND_ASSIGN(BufferAutoMapper);
  74 };
  75
  76 }  // namespace content
  77
  78 #endif  // CONTENT_RENDERER_PEPPER_PPB_BUFFER_IMPL_H_