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 
26 typedef off_t off64_t;
27 
lseek64(int fd,off64_t offset,int whence)28 static inline off64_t lseek64(int fd, off64_t offset, int whence) {
29     return lseek(fd, offset, whence);
30 }
31 
pread64(int fd,void * buf,size_t nbytes,off64_t offset)32 static 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