ios/web/weak_nsobject_counter.h

   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 #ifndef IOS_WEB_WEAK_NSOBJECT_COUNTER_H_
   6 #define IOS_WEB_WEAK_NSOBJECT_COUNTER_H_
   7
   8 #import <Foundation/Foundation.h>
   9
  10 #include "base/memory/linked_ptr.h"
  11 #include "base/threading/non_thread_safe.h"
  12
  13 namespace web {
  14
  15 // WeakNSObjectCounter is a class to maintain a counter of all the objects
  16 // that are added using |Insert| that are alive.
  17 // This class is not thread safe and objects must be destroyed and created on
  18 // the same thread.
  19 // TODO(stuartmorgan): Remove this once ARC is supported.
  20 class WeakNSObjectCounter : public base::NonThreadSafe {
  21  public:
  22   WeakNSObjectCounter();
  23   ~WeakNSObjectCounter();
  24   // Inserts an object. |object| cannot be nil.
  25   void Insert(id object);
  26   // Returns the count of all active objects that have been inserted.
  27   NSUInteger Size() const;
  28  private:
  29   // The object that maintains the number of active items.
  30   linked_ptr<NSUInteger> counter_;
  31 };
  32
  33 }  // namespace web
  34
  35 #endif  // IOS_WEB_WEAK_NSOBJECT_COUNTER_H_