1/*
2 * Copyright 2011 Google Inc. All Rights Reserved.
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#ifndef SFNTLY_CPP_SRC_SFNTLY_PORT_ATOMIC_H_
18#define SFNTLY_CPP_SRC_SFNTLY_PORT_ATOMIC_H_
19
20#if defined (WIN32)
21
22#include <windows.h>
23
24static inline size_t AtomicIncrement(size_t* address) {
25#if defined (_WIN64)
26  return InterlockedIncrement64(reinterpret_cast<LONGLONG*>(address));
27#else
28  return InterlockedIncrement(reinterpret_cast<LONG*>(address));
29#endif
30}
31
32static inline size_t AtomicDecrement(size_t* address) {
33#if defined (_WIN64)
34  return InterlockedDecrement64(reinterpret_cast<LONGLONG*>(address));
35#else
36  return InterlockedDecrement(reinterpret_cast<LONG*>(address));
37#endif
38}
39
40#elif defined (__APPLE__)
41
42#include <libkern/OSAtomic.h>
43
44static inline size_t AtomicIncrement(size_t* address) {
45  return OSAtomicIncrement32Barrier(reinterpret_cast<int32_t*>(address));
46}
47
48static inline size_t AtomicDecrement(size_t* address) {
49  return OSAtomicDecrement32Barrier(reinterpret_cast<int32_t*>(address));
50}
51
52// Originally we check __GCC_HAVE_SYNC_COMPARE_AND_SWAP_4, however, there are
53// issues that clang not carring over this definition.  Therefore we boldly
54// assume it's gcc or gcc-compatible here.  Compilation shall still fail since
55// the intrinsics used are GCC-specific.
56
57#else
58
59#include <stddef.h>
60
61static inline size_t AtomicIncrement(size_t* address) {
62  return __sync_add_and_fetch(address, 1);
63}
64
65static inline size_t AtomicDecrement(size_t* address) {
66  return __sync_sub_and_fetch(address, 1);
67}
68
69#endif  // WIN32
70
71#endif  // SFNTLY_CPP_SRC_SFNTLY_PORT_ATOMIC_H_
72