base/mac/scoped_mach_vm.cc

   1 // Copyright 2014 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 #include "base/mac/scoped_mach_vm.h"
   6
   7 namespace base {
   8 namespace mac {
   9
  10 void ScopedMachVM::reset(vm_address_t address, vm_size_t size) {
  11   DCHECK(address % PAGE_SIZE == 0);
  12   DCHECK(size % PAGE_SIZE == 0);
  13
  14   if (size_) {
  15     if (address_ < address) {
  16       vm_deallocate(mach_task_self(),
  17                     address_,
  18                     std::min(size_, address - address_));
  19     }
  20     if (address_ + size_ > address + size) {
  21       vm_address_t deallocate_start = std::max(address_, address + size);
  22       vm_deallocate(mach_task_self(),
  23                     deallocate_start,
  24                     address_ + size_ - deallocate_start);
  25     }
  26   }
  27
  28   address_ = address;
  29   size_ = size;
  30 }
  31
  32 }  // namespace mac
  33 }  // namespace base