gecko-dev/ipc/glue/SharedMemory_posix.cpp

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include <sys/mman.h>         // mprotect
#include <unistd.h>           // sysconf

#include "mozilla/ipc/SharedMemory.h"

namespace mozilla {
namespace ipc {

void
SharedMemory::SystemProtect(char* aAddr, size_t aSize, int aRights)
{
  int flags = 0;
  if (aRights & RightsRead)
    flags |= PROT_READ;
  if (aRights & RightsWrite)
    flags |= PROT_WRITE;
  if (RightsNone == aRights)
    flags = PROT_NONE;

  if (0 < mprotect(aAddr, aSize, flags))
    MOZ_CRASH("can't mprotect()");
}

size_t
SharedMemory::SystemPageSize()
{
  return sysconf(_SC_PAGESIZE);
}

} // namespace ipc
} // namespace mozilla