refcnt.hh revision 3877:2432a50b7d25
1/* 2 * Copyright (c) 2002-2005 The Regents of The University of Michigan 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions are 7 * met: redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer; 9 * 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 * neither the name of the copyright holders nor the names of its 13 * contributors may be used to endorse or promote products derived from 14 * this software without specific prior written permission. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 17 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 18 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 19 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 20 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 22 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 26 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 * 28 * Authors: Nathan Binkert 29 */ 30 31#ifndef __BASE_REFCNT_HH__ 32#define __BASE_REFCNT_HH__ 33 34class RefCounted 35{ 36 private: 37 int count; 38 39 private: 40 RefCounted(const RefCounted &); 41 42 public: 43 RefCounted() : count(0) {} 44 virtual ~RefCounted() {} 45 46 void incref() { ++count; } 47 void decref() { if (--count <= 0) delete this; } 48}; 49 50template <class T> 51class RefCountingPtr 52{ 53 protected: 54 T *data; 55 56 void copy(T *d) 57 { 58 data = d; 59 if (data) 60 data->incref(); 61 } 62 void del() 63 { 64 if (data) 65 data->decref(); 66 } 67 void set(T *d) 68 { 69 if (data == d) 70 return; 71 72 del(); 73 copy(d); 74 } 75 76 77 public: 78 RefCountingPtr() : data(0) {} 79 RefCountingPtr(T *data) { copy(data); } 80 RefCountingPtr(const RefCountingPtr &r) { copy(r.data); } 81 ~RefCountingPtr() { del(); } 82 83 T *operator->() { return data; } 84 T &operator*() { return *data; } 85 T *get() { return data; } 86 87 const T *operator->() const { return data; } 88 const T &operator*() const { return *data; } 89 const T *get() const { return data; } 90 91 const RefCountingPtr &operator=(T *p) { set(p); return *this; } 92 const RefCountingPtr &operator=(const RefCountingPtr &r) 93 { return operator=(r.data); } 94 95 bool operator!() const { return data == 0; } 96 operator bool() const { return data != 0; } 97}; 98 99template<class T> 100bool operator==(const RefCountingPtr<T> &l, const RefCountingPtr<T> &r) 101{ return l.get() == r.get(); } 102 103template<class T> 104bool operator==(const RefCountingPtr<T> &l, const T *r) 105{ return l.get() == r; } 106 107template<class T> 108bool operator==(const T &l, const RefCountingPtr<T> &r) 109{ return l == r.get(); } 110 111template<class T> 112bool operator!=(const RefCountingPtr<T> &l, const RefCountingPtr<T> &r) 113{ return l.get() != r.get(); } 114 115template<class T> 116bool operator!=(const RefCountingPtr<T> &l, const T *r) 117{ return l.get() != r; } 118 119template<class T> 120bool operator!=(const T &l, const RefCountingPtr<T> &r) 121{ return l != r.get(); } 122 123#endif // __BASE_REFCNT_HH__ 124