base/mac/scoped_ioobject.h

   1 // Copyright (c) 2012 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 #ifndef BASE_MAC_SCOPED_IOOBJECT_H_
   6 #define BASE_MAC_SCOPED_IOOBJECT_H_
   7
   8 #include <IOKit/IOKitLib.h>
   9
  10 #include "base/basictypes.h"
  11 #include "base/compiler_specific.h"
  12
  13 namespace base {
  14 namespace mac {
  15
  16 // Just like ScopedCFTypeRef but for io_object_t and subclasses.
  17 template<typename IOT>
  18 class ScopedIOObject {
  19  public:
  20   typedef IOT element_type;
  21
  22   explicit ScopedIOObject(IOT object = IO_OBJECT_NULL)
  23       : object_(object) {
  24   }
  25
  26   ~ScopedIOObject() {
  27     if (object_)
  28       IOObjectRelease(object_);
  29   }
  30
  31   void reset(IOT object = IO_OBJECT_NULL) {
  32     if (object_)
  33       IOObjectRelease(object_);
  34     object_ = object;
  35   }
  36
  37   bool operator==(IOT that) const {
  38     return object_ == that;
  39   }
  40
  41   bool operator!=(IOT that) const {
  42     return object_ != that;
  43   }
  44
  45   operator IOT() const {
  46     return object_;
  47   }
  48
  49   IOT get() const {
  50     return object_;
  51   }
  52
  53   void swap(ScopedIOObject& that) {
  54     IOT temp = that.object_;
  55     that.object_ = object_;
  56     object_ = temp;
  57   }
  58
  59   IOT release() WARN_UNUSED_RESULT {
  60     IOT temp = object_;
  61     object_ = IO_OBJECT_NULL;
  62     return temp;
  63   }
  64
  65  private:
  66   IOT object_;
  67
  68   DISALLOW_COPY_AND_ASSIGN(ScopedIOObject);
  69 };
  70
  71 }  // namespace mac
  72 }  // namespace base
  73
  74 #endif  // BASE_MAC_SCOPED_IOOBJECT_H_