1 /*
2 * Copyright (C) 2007, 2008, 2010 Apple Inc. All rights reserved.
3 * Copyright (C) 2007 Justin Haygood (jhaygood@reaktix.com)
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * 3. Neither the name of Apple Computer, Inc. ("Apple") nor the names of
15 * its contributors may be used to endorse or promote products derived
16 * from this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
19 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
20 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
21 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
22 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
23 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
24 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
25 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 *
29 *
30 * Note: The implementations of InterlockedIncrement and InterlockedDecrement are based
31 * on atomic_increment and atomic_exchange_and_add from the Boost C++ Library. The license
32 * is virtually identical to the Apple license above but is included here for completeness.
33 *
34 * Boost Software License - Version 1.0 - August 17th, 2003
35 *
36 * Permission is hereby granted, free of charge, to any person or organization
37 * obtaining a copy of the software and accompanying documentation covered by
38 * this license (the "Software") to use, reproduce, display, distribute,
39 * execute, and transmit the Software, and to prepare derivative works of the
40 * Software, and to permit third-parties to whom the Software is furnished to
41 * do so, all subject to the following:
42 *
43 * The copyright notices in the Software and this entire statement, including
44 * the above license grant, this restriction and the following disclaimer,
45 * must be included in all copies of the Software, in whole or in part, and
46 * all derivative works of the Software, unless such copies or derivative
47 * works are solely in the form of machine-executable object code generated by
48 * a source language processor.
49 *
50 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
51 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
52 * FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT
53 * SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE
54 * FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE,
55 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
56 * DEALINGS IN THE SOFTWARE.
57 */
58
59 #ifndef Atomics_h
60 #define Atomics_h
61
62 #include "Platform.h"
63
64 #if OS(WINDOWS)
65 #include <windows.h>
66 #elif OS(ANDROID)
67 #include <cutils/atomic.h>
68 #elif OS(QNX)
69 #include <atomic.h>
70 #endif
71
72 namespace WTF {
73
74 #if OS(WINDOWS)
75 #define WTF_USE_LOCKFREE_THREADSAFEREFCOUNTED 1
76
77 #if COMPILER(MINGW) || COMPILER(MSVC7_OR_LOWER) || OS(WINCE)
atomicIncrement(int * addend)78 inline int atomicIncrement(int* addend) { return InterlockedIncrement(reinterpret_cast<long*>(addend)); }
atomicDecrement(int * addend)79 inline int atomicDecrement(int* addend) { return InterlockedDecrement(reinterpret_cast<long*>(addend)); }
80 #else
81 inline int atomicIncrement(int volatile* addend) { return InterlockedIncrement(reinterpret_cast<long volatile*>(addend)); }
82 inline int atomicDecrement(int volatile* addend) { return InterlockedDecrement(reinterpret_cast<long volatile*>(addend)); }
83 #endif
84
85 #elif OS(ANDROID)
86
87 inline int atomicIncrement(int volatile* addend) { return android_atomic_inc(addend); }
88 inline int atomicDecrement(int volatile* addend) { return android_atomic_dec(addend); }
89
90 #elif OS(QNX)
91
92 inline int atomicIncrement(int volatile* addend) { return (int) atomic_add_value((unsigned int volatile*)addend, 1); }
93 inline int atomicDecrement(int volatile* addend) { return (int) atomic_sub_value((unsigned int volatile*)addend, 1); }
94
95 #elif COMPILER(GCC) && !CPU(SPARC64) && !OS(SYMBIAN) // sizeof(_Atomic_word) != sizeof(int) on sparc64 gcc
96 #define WTF_USE_LOCKFREE_THREADSAFEREFCOUNTED 1
97
98 inline int atomicIncrement(int volatile* addend) { return __sync_add_and_fetch(addend, 1); }
99 inline int atomicDecrement(int volatile* addend) { return __sync_sub_and_fetch(addend, 1); }
100
101 #endif
102
103 } // namespace WTF
104
105 #if USE(LOCKFREE_THREADSAFEREFCOUNTED)
106 using WTF::atomicDecrement;
107 using WTF::atomicIncrement;
108 #endif
109
110 #endif // Atomics_h
111