ipc/glue/SharedMemoryBasic_chromium.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_chromium_h
   9 #define mozilla_ipc_SharedMemoryBasic_chromium_h
  10
  11 #include "base/shared_memory.h"
  12 #include "SharedMemory.h"
  13
  14 #include "nsDebug.h"
  15
  16 //
  17 // This is a low-level wrapper around platform shared memory.  Don't
  18 // use it directly; use Shmem allocated through IPDL interfaces.
  19 //
  20
  21 namespace mozilla {
  22 namespace ipc {
  23
  24 class SharedMemoryBasic final : public SharedMemory
  25 {
  26 public:
  27   typedef base::SharedMemoryHandle Handle;
  28
  29   SharedMemoryBasic()
  30   {
  31   }
  32
  33   explicit SharedMemoryBasic(const Handle& aHandle)
  34     : mSharedMemory(aHandle, false)
  35   {
  36   }
  37
  38   virtual bool Create(size_t aNbytes) override
  39   {
  40     bool ok = mSharedMemory.Create("", false, false, aNbytes);
  41     if (ok) {
  42       Created(aNbytes);
  43     }
  44     return ok;
  45   }
  46
  47   virtual bool Map(size_t nBytes) override
  48   {
  49     bool ok = mSharedMemory.Map(nBytes);
  50     if (ok) {
  51       Mapped(nBytes);
  52     }
  53     return ok;
  54   }
  55
  56   virtual void* memory() const override
  57   {
  58     return mSharedMemory.memory();
  59   }
  60
  61   virtual SharedMemoryType Type() const override
  62   {
  63     return TYPE_BASIC;
  64   }
  65
  66   static Handle NULLHandle()
  67   {
  68     return base::SharedMemory::NULLHandle();
  69   }
  70
  71   static bool IsHandleValid(const Handle &aHandle)
  72   {
  73     return base::SharedMemory::IsHandleValid(aHandle);
  74   }
  75
  76   bool ShareToProcess(base::ProcessHandle process,
  77                       Handle* new_handle)
  78   {
  79     base::SharedMemoryHandle handle;
  80     bool ret = mSharedMemory.ShareToProcess(process, &handle);
  81     if (ret)
  82       *new_handle = handle;
  83     return ret;
  84   }
  85
  86 private:
  87   ~SharedMemoryBasic()
  88   {
  89   }
  90
  91   base::SharedMemory mSharedMemory;
  92 };
  93
  94 } // namespace ipc
  95 } // namespace mozilla
  96
  97
  98 #endif // ifndef mozilla_ipc_SharedMemoryBasic_chromium_h