1 | /* |
2 | * Copyright (C) 2009 Google 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 are |
6 | * met: |
7 | * |
8 | * * Redistributions of source code must retain the above copyright |
9 | * notice, this list of conditions and the following disclaimer. |
10 | * * Redistributions in binary form must reproduce the above |
11 | * copyright notice, this list of conditions and the following disclaimer |
12 | * in the documentation and/or other materials provided with the |
13 | * distribution. |
14 | * * Neither the name of Google Inc. nor the names of its |
15 | * contributors may be used to endorse or promote products derived from |
16 | * this software without specific prior written permission. |
17 | * |
18 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
19 | * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
20 | * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
21 | * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
22 | * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
23 | * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
24 | * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
25 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
26 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
27 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
28 | * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
29 | */ |
30 | |
31 | #ifndef PtrAndFlags_h |
32 | #define PtrAndFlags_h |
33 | |
34 | #include <wtf/Assertions.h> |
35 | |
36 | namespace WTF { |
37 | template<class T, typename FlagEnum> class PtrAndFlagsBase { |
38 | public: |
39 | bool isFlagSet(FlagEnum flagNumber) const { ASSERT(flagNumber < 2); return m_ptrAndFlags & (1 << flagNumber); } |
40 | void setFlag(FlagEnum flagNumber) { ASSERT(flagNumber < 2); m_ptrAndFlags |= (1 << flagNumber);} |
41 | void clearFlag(FlagEnum flagNumber) { ASSERT(flagNumber < 2); m_ptrAndFlags &= ~(1 << flagNumber);} |
42 | T* get() const { return reinterpret_cast<T*>(m_ptrAndFlags & ~3); } |
43 | void set(T* ptr) |
44 | { |
45 | ASSERT(!(reinterpret_cast<intptr_t>(ptr) & 3)); |
46 | m_ptrAndFlags = reinterpret_cast<intptr_t>(ptr) | (m_ptrAndFlags & 3); |
47 | #ifndef NDEBUG |
48 | m_leaksPtr = ptr; |
49 | #endif |
50 | } |
51 | |
52 | bool operator!() const { return !get(); } |
53 | T* operator->() const { return reinterpret_cast<T*>(m_ptrAndFlags & ~3); } |
54 | |
55 | protected: |
56 | intptr_t m_ptrAndFlags; |
57 | #ifndef NDEBUG |
58 | void* m_leaksPtr; // Only used to allow tools like leaks on OSX to detect that the memory is referenced. |
59 | #endif |
60 | }; |
61 | |
62 | template<class T, typename FlagEnum> class PtrAndFlags : public PtrAndFlagsBase<T, FlagEnum> { |
63 | public: |
64 | PtrAndFlags() |
65 | { |
66 | PtrAndFlagsBase<T, FlagEnum>::m_ptrAndFlags = 0; |
67 | } |
68 | PtrAndFlags(T* ptr) |
69 | { |
70 | PtrAndFlagsBase<T, FlagEnum>::m_ptrAndFlags = 0; |
71 | PtrAndFlagsBase<T, FlagEnum>::set(ptr); |
72 | } |
73 | }; |
74 | } // namespace WTF |
75 | |
76 | using WTF::PtrAndFlagsBase; |
77 | using WTF::PtrAndFlags; |
78 | |
79 | #endif // PtrAndFlags_h |
80 | |