1 /*
2  * Copyright (C) 2014 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 // Base class for reference counted objects in Minikin
18 
19 #ifndef MINIKIN_REF_COUNTED_H
20 #define MINIKIN_REF_COUNTED_H
21 
22 namespace android {
23 
24 class MinikinRefCounted {
25 public:
RefLocked()26     void RefLocked() { mRefcount_++; }
UnrefLocked()27     void UnrefLocked() { if (--mRefcount_ == 0) { delete this; } }
28 
29     // These refcount operations take the global lock.
30     void Ref();
31     void Unref();
32 
MinikinRefCounted()33     MinikinRefCounted() : mRefcount_(1) { }
34 
~MinikinRefCounted()35     virtual ~MinikinRefCounted() { };
36 private:
37     int mRefcount_;
38 };
39 
40 // An RAII container for reference counted objects.
41 // Note: this is only suitable for clients which are _not_ holding the global lock.
42 template <typename T>
43 class MinikinAutoUnref {
44 public:
MinikinAutoUnref(T * obj)45     MinikinAutoUnref(T* obj) : mObj(obj) {
46     }
~MinikinAutoUnref()47     ~MinikinAutoUnref() {
48         mObj->Unref();
49     }
50     T& operator*() const { return *mObj; }
51     T* operator->() const { return mObj; }
get()52     T* get() const { return mObj; }
53 private:
54     T* mObj;
55 };
56 
57 }
58 
59 #endif   // MINIKIN_REF_COUNTED_H