ipc/glue/SharedMemoryBasic_chromium.h
author Jeff Walden <jwalden@mit.edu>
Wed, 28 Mar 2012 15:42:40 -0700
changeset 93888 732633ac1e07036c6e3dce6eceba4dac9210c76a
parent 56910 ffb9040a013b85de49d83fe36d8b52609932b0b9
child 98529 f4157e8c410708d76703f19e4dfb61859bfe32d8
permissions -rw-r--r--
Document macro naming style and struct naming style in C-compatible code, where C++ namespaces can't be used to avoid name collisions. No bug, r=luke over IRC, DONTBUILD because this is modifying docs but touching no code

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 * vim: sw=2 ts=8 et :
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 *
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 * for the specific language governing rights and limitations under the
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#ifndef mozilla_ipc_SharedMemoryBasic_chromium_h
#define mozilla_ipc_SharedMemoryBasic_chromium_h

#include "base/shared_memory.h"
#include "SharedMemory.h"

#include "nsDebug.h"

//
// This is a low-level wrapper around platform shared memory.  Don't
// use it directly; use Shmem allocated through IPDL interfaces.
//

namespace mozilla {
namespace ipc {

class SharedMemoryBasic : public SharedMemory
{
public:
  typedef base::SharedMemoryHandle Handle;

  SharedMemoryBasic()
  {
  }

  SharedMemoryBasic(const Handle& aHandle)
    : mSharedMemory(aHandle, false)
  {
  }

  NS_OVERRIDE
  virtual bool Create(size_t aNbytes)
  {
    bool ok = mSharedMemory.Create("", false, false, aNbytes);
    if (ok) {
      Created(aNbytes);
    }
    return ok;
  }

  NS_OVERRIDE
  virtual bool Map(size_t nBytes)
  {
    bool ok = mSharedMemory.Map(nBytes);
    if (ok) {
      Mapped(nBytes);
    }
    return ok;
  }

  NS_OVERRIDE
  virtual void* memory() const
  {
    return mSharedMemory.memory();
  }

  NS_OVERRIDE
  virtual SharedMemoryType Type() const
  {
    return TYPE_BASIC;
  }

  static Handle NULLHandle()
  {
    return base::SharedMemory::NULLHandle();
  }

  static bool IsHandleValid(const Handle &aHandle)
  {
    return base::SharedMemory::IsHandleValid(aHandle);
  }

  bool ShareToProcess(base::ProcessHandle process,
                      Handle* new_handle)
  {
    base::SharedMemoryHandle handle;
    bool ret = mSharedMemory.ShareToProcess(process, &handle);
    if (ret)
      *new_handle = handle;
    return ret;
  }

private:
  base::SharedMemory mSharedMemory;
};

} // namespace ipc
} // namespace mozilla


#endif // ifndef mozilla_ipc_SharedMemoryBasic_chromium_h