1// Copyright 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_CFFILEDESCRIPTORREF_H_
6#define BASE_MAC_SCOPED_CFFILEDESCRIPTORREF_H_
7
8#include <CoreFoundation/CoreFoundation.h>
9
10#include "base/basictypes.h"
11#include "base/compiler_specific.h"
12
13namespace base {
14namespace mac {
15
16// ScopedCFFileDescriptorRef is designed after ScopedCFTypeRef<>. On
17// destruction, it will invalidate the file descriptor.
18// ScopedCFFileDescriptorRef (unlike ScopedCFTypeRef<>) does not support RETAIN
19// semantics, copying, or assignment, as doing so would increase the chances
20// that a file descriptor is invalidated while still in use.
21class ScopedCFFileDescriptorRef {
22 public:
23  explicit ScopedCFFileDescriptorRef(CFFileDescriptorRef fdref = NULL)
24      : fdref_(fdref) {
25  }
26
27  ~ScopedCFFileDescriptorRef() {
28    if (fdref_) {
29      CFFileDescriptorInvalidate(fdref_);
30      CFRelease(fdref_);
31    }
32  }
33
34  void reset(CFFileDescriptorRef fdref = NULL) {
35    if (fdref_ == fdref)
36      return;
37    if (fdref_) {
38      CFFileDescriptorInvalidate(fdref_);
39      CFRelease(fdref_);
40    }
41    fdref_ = fdref;
42  }
43
44  bool operator==(CFFileDescriptorRef that) const {
45    return fdref_ == that;
46  }
47
48  bool operator!=(CFFileDescriptorRef that) const {
49    return fdref_ != that;
50  }
51
52  operator CFFileDescriptorRef() const {
53    return fdref_;
54  }
55
56  CFFileDescriptorRef get() const {
57    return fdref_;
58  }
59
60  CFFileDescriptorRef release() WARN_UNUSED_RESULT {
61    CFFileDescriptorRef temp = fdref_;
62    fdref_ = NULL;
63    return temp;
64  }
65
66 private:
67  CFFileDescriptorRef fdref_;
68
69  DISALLOW_COPY_AND_ASSIGN(ScopedCFFileDescriptorRef);
70};
71
72}  // namespace mac
73}  // namespace base
74
75#endif  // BASE_MAC_SCOPED_CFFILEDESCRIPTORREF_H_
76