base/mac/scoped_nsautorelease_pool.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_MAC_SCOPED_NSAUTORELEASE_POOL_H_
   6 #define BASE_MAC_SCOPED_NSAUTORELEASE_POOL_H_
   7 #pragma once
   8
   9 #include "base/basictypes.h"
  10
  11 #if defined(OS_MACOSX)
  12 #if defined(__OBJC__)
  13 @class NSAutoreleasePool;
  14 #else  // __OBJC__
  15 class NSAutoreleasePool;
  16 #endif  // __OBJC__
  17 #endif  // OS_MACOSX
  18
  19 namespace base {
  20 namespace mac {
  21
  22 // On the Mac, ScopedNSAutoreleasePool allocates an NSAutoreleasePool when
  23 // instantiated and sends it a -drain message when destroyed.  This allows an
  24 // autorelease pool to be maintained in ordinary C++ code without bringing in
  25 // any direct Objective-C dependency.
  26 //
  27 // On other platforms, ScopedNSAutoreleasePool is an empty object with no
  28 // effects.  This allows it to be used directly in cross-platform code without
  29 // ugly #ifdefs.
  30 class ScopedNSAutoreleasePool {
  31  public:
  32 #if !defined(OS_MACOSX)
  33   ScopedNSAutoreleasePool() {}
  34   void Recycle() { }
  35 #else  // OS_MACOSX
  36   ScopedNSAutoreleasePool();
  37   ~ScopedNSAutoreleasePool();
  38
  39   // Clear out the pool in case its position on the stack causes it to be
  40   // alive for long periods of time (such as the entire length of the app).
  41   // Only use then when you're certain the items currently in the pool are
  42   // no longer needed.
  43   void Recycle();
  44  private:
  45   NSAutoreleasePool* autorelease_pool_;
  46 #endif  // OS_MACOSX
  47
  48  private:
  49   DISALLOW_COPY_AND_ASSIGN(ScopedNSAutoreleasePool);
  50 };
  51
  52 }  // namespace mac
  53 }  // namespace base
  54
  55 #endif  // BASE_MAC_SCOPED_NSAUTORELEASE_POOL_H_