base/scoped_aedesc.h

   1 // Copyright (c) 2010 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_SCOPED_AEDESC_H_
   6 #define BASE_SCOPED_AEDESC_H_
   7 #pragma once
   8
   9 #import <CoreServices/CoreServices.h>
  10
  11 #include "base/basictypes.h"
  12
  13 // The scoped_aedesc is used to scope AppleEvent descriptors.  On creation,
  14 // it will store a NULL descriptor.  On destruction, it will dispose of the
  15 // descriptor.
  16 //
  17 // This class is parameterized for additional type safety checks.  You can use
  18 // the generic AEDesc type by not providing a template parameter:
  19 //  scoped_aedesc<> desc;
  20 template <typename AEDescType = AEDesc>
  21 class scoped_aedesc {
  22  public:
  23   scoped_aedesc() {
  24     AECreateDesc(typeNull, NULL, 0, &desc_);
  25   }
  26
  27   ~scoped_aedesc() {
  28     AEDisposeDesc(&desc_);
  29   }
  30
  31   // Used for in parameters.
  32   operator const AEDescType*() {
  33     return &desc_;
  34   }
  35
  36   // Used for out parameters.
  37   AEDescType* OutPointer() {
  38     return &desc_;
  39   }
  40
  41  private:
  42   AEDescType desc_;
  43
  44   DISALLOW_COPY_AND_ASSIGN(scoped_aedesc);
  45 };
  46
  47 #endif  // BASE_SCOPED_AEDESC_H_