1/*
2 * Copyright (C) 2013 Apple Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 *    notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 *    notice, this list of conditions and the following disclaimer in the
11 *    documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
14 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
15 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
17 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
18 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
19 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
20 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
21 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
22 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
23 * THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#ifndef MallocPtr_h
27#define MallocPtr_h
28
29// MallocPtr is a smart pointer class that calls fastFree in its destructor.
30// It is intended to be used for pointers where the C++ lifetime semantics
31// (calling constructors and destructors) is not desired.
32
33namespace WTF {
34
35template<typename T> class MallocPtr {
36public:
37    MallocPtr()
38        : m_ptr(nullptr)
39    {
40    }
41
42    MallocPtr(std::nullptr_t)
43        : m_ptr(nullptr)
44    {
45    }
46
47    MallocPtr(MallocPtr&& other)
48        : m_ptr(other.leakPtr())
49    {
50    }
51
52    ~MallocPtr()
53    {
54        fastFree(m_ptr);
55    }
56
57    T* get() const
58    {
59        return m_ptr;
60    }
61
62    T *leakPtr() WARN_UNUSED_RETURN
63    {
64        T* ptr = m_ptr;
65        m_ptr = nullptr;
66        return ptr;
67    }
68
69    bool operator!() const
70    {
71        return !m_ptr;
72    }
73
74    MallocPtr& operator=(MallocPtr&& other)
75    {
76        MallocPtr ptr = WTF::move(other);
77        swap(ptr);
78
79        return *this;
80    }
81
82    void swap(MallocPtr& other)
83    {
84        std::swap(m_ptr, other.m_ptr);
85    }
86
87    template<typename U> friend MallocPtr<U> adoptMallocPtr(U*);
88
89    static MallocPtr malloc(size_t size)
90    {
91        MallocPtr mallocPtr;
92        mallocPtr.m_ptr = static_cast<T*>(fastMalloc(size));
93
94        return mallocPtr;
95    }
96
97    void realloc(size_t newSize)
98    {
99        m_ptr = static_cast<T*>(fastRealloc(m_ptr, newSize));
100    }
101
102private:
103    explicit MallocPtr(T* ptr)
104        : m_ptr(ptr)
105    {
106    }
107
108    T* m_ptr;
109};
110
111template<typename U> MallocPtr<U> adoptMallocPtr(U* ptr)
112{
113    return MallocPtr<U>(ptr);
114}
115
116} // namespace WTF
117
118using WTF::MallocPtr;
119using WTF::adoptMallocPtr;
120
121#endif // MallocPtr_h
122