1/*
2 * Copyright (C) 2010 The Android Open Source Project
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 __LIB_UTILS_COMPAT_H
18#define __LIB_UTILS_COMPAT_H
19
20#include <unistd.h>
21
22#if defined(__APPLE__)
23
24/* Mac OS has always had a 64-bit off_t, so it doesn't have off64_t. */
25
26typedef off_t off64_t;
27
28static inline off64_t lseek64(int fd, off64_t offset, int whence) {
29    return lseek(fd, offset, whence);
30}
31
32static inline ssize_t pread64(int fd, void* buf, size_t nbytes, off64_t offset) {
33    return pread(fd, buf, nbytes, offset);
34}
35
36#endif /* __APPLE__ */
37
38#if defined(_WIN32)
39#define O_CLOEXEC O_NOINHERIT
40#define O_NOFOLLOW 0
41#define DEFFILEMODE 0666
42#endif /* _WIN32 */
43
44#if defined(_WIN32)
45#define ZD "%ld"
46#define ZD_TYPE long
47#else
48#define ZD "%zd"
49#define ZD_TYPE ssize_t
50#endif
51
52/*
53 * Needed for cases where something should be constexpr if possible, but not
54 * being constexpr is fine if in pre-C++11 code (such as a const static float
55 * member variable).
56 */
57#if __cplusplus >= 201103L
58#define CONSTEXPR constexpr
59#else
60#define CONSTEXPR
61#endif
62
63/*
64 * TEMP_FAILURE_RETRY is defined by some, but not all, versions of
65 * <unistd.h>. (Alas, it is not as standard as we'd hoped!) So, if it's
66 * not already defined, then define it here.
67 */
68#ifndef TEMP_FAILURE_RETRY
69/* Used to retry syscalls that can return EINTR. */
70#define TEMP_FAILURE_RETRY(exp) ({         \
71    typeof (exp) _rc;                      \
72    do {                                   \
73        _rc = (exp);                       \
74    } while (_rc == -1 && errno == EINTR); \
75    _rc; })
76#endif
77
78#endif /* __LIB_UTILS_COMPAT_H */
79