ipc/glue/SharedMemoryBasic_android.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
   2  * vim: sw=2 ts=8 et :
   3  */
   4 /* This Source Code Form is subject to the terms of the Mozilla Public
   5  * License, v. 2.0. If a copy of the MPL was not distributed with this
   6  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   7
   8 #ifndef mozilla_ipc_SharedMemoryBasic_android_h
   9 #define mozilla_ipc_SharedMemoryBasic_android_h
  10
  11 #include "base/file_descriptor_posix.h"
  12
  13 #include "SharedMemory.h"
  14
  15 //
  16 // This is a low-level wrapper around platform shared memory.  Don't
  17 // use it directly; use Shmem allocated through IPDL interfaces.
  18 //
  19
  20 namespace mozilla {
  21 namespace ipc {
  22
  23 class SharedMemoryBasic MOZ_FINAL : public SharedMemory
  24 {
  25 public:
  26   typedef base::FileDescriptor Handle;
  27
  28   SharedMemoryBasic();
  29
  30   SharedMemoryBasic(const Handle& aHandle);
  31
  32   virtual bool Create(size_t aNbytes) MOZ_OVERRIDE;
  33
  34   virtual bool Map(size_t nBytes) MOZ_OVERRIDE;
  35
  36   virtual void* memory() const MOZ_OVERRIDE
  37   {
  38     return mMemory;
  39   }
  40
  41   virtual SharedMemoryType Type() const MOZ_OVERRIDE
  42   {
  43     return TYPE_BASIC;
  44   }
  45
  46   static Handle NULLHandle()
  47   {
  48     return Handle();
  49   }
  50
  51   static bool IsHandleValid(const Handle &aHandle)
  52   {
  53     return aHandle.fd >= 0;
  54   }
  55
  56   bool ShareToProcess(base::ProcessHandle aProcess,
  57                       Handle* aNewHandle);
  58
  59 private:
  60   ~SharedMemoryBasic();
  61
  62   void Unmap();
  63   void Destroy();
  64
  65   // The /dev/ashmem fd we allocate.
  66   int mShmFd;
  67   // Pointer to mapped region, null if unmapped.
  68   void *mMemory;
  69 };
  70
  71 } // namespace ipc
  72 } // namespace mozilla
  73
  74 #endif // ifndef mozilla_ipc_SharedMemoryBasic_android_h