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: isFlagSet(FlagEnum flagNumber)39 bool isFlagSet(FlagEnum flagNumber) const { ASSERT(flagNumber < 2); return m_ptrAndFlags & (1 << flagNumber); } setFlag(FlagEnum flagNumber)40 void setFlag(FlagEnum flagNumber) { ASSERT(flagNumber < 2); m_ptrAndFlags |= (1 << flagNumber);} clearFlag(FlagEnum flagNumber)41 void clearFlag(FlagEnum flagNumber) { ASSERT(flagNumber < 2); m_ptrAndFlags &= ~(1 << flagNumber);} get()42 T* get() const { return reinterpret_cast<T*>(m_ptrAndFlags & ~3); } set(T * ptr)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: PtrAndFlags()64 PtrAndFlags() 65 { 66 PtrAndFlagsBase<T, FlagEnum>::m_ptrAndFlags = 0; 67 } PtrAndFlags(T * ptr)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