1 // Workarounds for horrible build environment idiosyncrasies.
2
3 // Instead of polluting the code with strange #ifdefs to work around bugs
4 // in specific compiler, library, or OS versions, localize all that here
5 // and in portability.c
6
7 // For musl
8 #define _ALL_SOURCE
9
10 // Test for gcc (using compiler builtin #define)
11
12 #ifdef __GNUC__
13 #define noreturn __attribute__((noreturn))
14 #define printf_format __attribute__((format(printf, 1, 2)))
15 #else
16 #define noreturn
17 #define printf_format
18 #endif
19
20 // Always use long file support.
21 #define _FILE_OFFSET_BITS 64
22
23 // This isn't in the spec, but it's how we determine what libc we're using.
24
25 #include <features.h>
26
27 // Types various replacement prototypes need
28 #include <sys/types.h>
29
30 // Various constants old build environments might not have even if kernel does
31
32 #ifndef AT_FDCWD
33 #define AT_FDCWD -100
34 #endif
35
36 #ifndef AT_SYMLINK_NOFOLLOW
37 #define AT_SYMLINK_NOFOLLOW 0x100
38 #endif
39
40 #ifndef AT_REMOVEDIR
41 #define AT_REMOVEDIR 0x200
42 #endif
43
44 #ifndef RLIMIT_RTTIME
45 #define RLIMIT_RTTIME 15
46 #endif
47
48 // We don't define GNU_dammit because we're not part of the gnu project, and
49 // don't want to get any FSF on us. Unfortunately glibc (gnu libc)
50 // won't give us Linux syscall wrappers without claiming to be part of the
51 // gnu project (because Stallman's "GNU owns Linux" revisionist history
52 // crusade includes the kernel, even though Linux was inspired by Minix).
53
54 // We use most non-posix Linux syscalls directly through the syscall() wrapper,
55 // but even many posix-2008 functions aren't provided by glibc unless you
56 // claim it's in the name of Gnu.
57
58 #if defined(__GLIBC__)
59 // "Function prototypes shall be provided." but aren't.
60 // http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/unistd.h.html
61 char *crypt(const char *key, const char *salt);
62
63 // According to posix, #include header, get a function definition. But glibc...
64 // http://pubs.opengroup.org/onlinepubs/9699919799/functions/wcwidth.html
65 #include <wchar.h>
66 int wcwidth(wchar_t wc);
67
68 // see http://pubs.opengroup.org/onlinepubs/9699919799/functions/strptime.html
69 #include <time.h>
70 char *strptime(const char *buf, const char *format, struct tm *tm);
71
72 // They didn't like posix basename so they defined another function with the
73 // same name and if you include libgen.h it #defines basename to something
74 // else (where they implemented the real basename), and that define breaks
75 // the table entry for the basename command. They didn't make a new function
76 // with a different name for their new behavior because gnu.
77 //
78 // Solution: don't use their broken header, provide an inline to redirect the
79 // correct name to the broken name.
80
81 char *dirname(char *path);
82 char *__xpg_basename(char *path);
basename(char * path)83 static inline char *basename(char *path) { return __xpg_basename(path); }
84
85 // uClibc pretends to be glibc and copied a lot of its bugs, but has a few more
86 #if defined(__UCLIBC__)
87 #include <unistd.h>
88 #include <stdio.h>
89 ssize_t getdelim(char **lineptr, size_t *n, int delim, FILE *stream);
90 char *stpcpy(char *dest, const char *src);
91 pid_t getsid(pid_t pid);
92
93 // uClibc's last-ever release was in 2012, so of course it doesn't define
94 // any flag newer than MS_MOVE, which was added in 2001 (linux 2.5.0.5),
95 // eleven years earlier.
96
97 #include <sys/mount.h>
98 #ifndef MS_MOVE
99 #define MS_MOVE (1<<13)
100 #endif
101 #ifndef MS_REC
102 #define MS_REC (1<<14)
103 #endif
104 #ifndef MS_SILENT
105 #define MS_SILENT (1<<15)
106 #endif
107 #ifndef MS_UNBINDABLE
108 #define MS_UNBINDABLE (1<<17)
109 #endif
110 #ifndef MS_PRIVATE
111 #define MS_PRIVATE (1<<18)
112 #endif
113 #ifndef MS_SLAVE
114 #define MS_SLAVE (1<<19)
115 #endif
116 #ifndef MS_SHARED
117 #define MS_SHARED (1<<20)
118 #endif
119
120 // When building under obsolete glibc (Ubuntu 8.04-ish), hold its hand a bit.
121 #elif __GLIBC__ == 2 && __GLIBC_MINOR__ < 10
122 #define fstatat fstatat64
123 int fstatat64(int dirfd, const char *pathname, void *buf, int flags);
124 int readlinkat(int dirfd, const char *pathname, char *buf, size_t bufsiz);
125 char *stpcpy(char *dest, const char *src);
126 #include <sys/stat.h>
127 int fchmodat(int dirfd, const char *pathname, mode_t mode, int flags);
128 int openat(int dirfd, const char *pathname, int flags, ...);
129 #include <dirent.h>
130 DIR *fdopendir(int fd);
131 #include <unistd.h>
132 int fchownat(int dirfd, const char *pathname,
133 uid_t owner, gid_t group, int flags);
134 int isblank(int c);
135 int unlinkat(int dirfd, const char *pathname, int flags);
136 #include <stdio.h>
137 ssize_t getdelim(char **lineptr, size_t *n, int delim, FILE *stream);
138
139 // Straight from posix-2008, things old glibc had but didn't prototype
140
141 int faccessat(int fd, const char *path, int amode, int flag);
142 int linkat(int fd1, const char *path1, int fd2, const char *path2, int flag);
143 int mkdirat(int fd, const char *path, mode_t mode);
144 int symlinkat(const char *path1, int fd, const char *path2);
145 int mknodat(int fd, const char *path, mode_t mode, dev_t dev);
146 #include <sys/time.h>
147 int futimens(int fd, const struct timespec times[2]);
148 int utimensat(int fd, const char *path, const struct timespec times[2], int flag);
149
150 #ifndef MNT_DETACH
151 #define MNT_DETACH 2
152 #endif
153 #endif // Old glibc
154
155 #endif // glibc in general
156
157 #if !defined(__GLIBC__) && !defined(__BIONIC__)
158 // POSIX basename.
159 #include <libgen.h>
160 #endif
161
162 // glibc was handled above; for 32-bit bionic we need to avoid a collision
163 // with toybox's basename_r so we can't include <libgen.h> even though that
164 // would give us a POSIX basename(3).
165 #if defined(__BIONIC__)
166 char *basename(char *path);
167 char *dirname(char *path);
168 #endif
169
170 // Work out how to do endianness
171
172 #ifndef __APPLE__
173 #include <byteswap.h>
174 #include <endian.h>
175
176 #if __BYTE_ORDER == __BIG_ENDIAN
177 #define IS_BIG_ENDIAN 1
178 #else
179 #define IS_BIG_ENDIAN 0
180 #endif
181
182 int clearenv(void);
183 #else
184
185 #ifdef __BIG_ENDIAN__
186 #define IS_BIG_ENDIAN 1
187 #else
188 #define IS_BIG_ENDIAN 0
189 #endif
190
191 #endif
192
193 #if IS_BIG_ENDIAN
194 #define IS_LITTLE_ENDIAN 0
195 #define SWAP_BE16(x) (x)
196 #define SWAP_BE32(x) (x)
197 #define SWAP_BE64(x) (x)
198 #define SWAP_LE16(x) bswap_16(x)
199 #define SWAP_LE32(x) bswap_32(x)
200 #define SWAP_LE64(x) bswap_64(x)
201 #else
202 #define IS_LITTLE_ENDIAN 1
203 #define SWAP_BE16(x) bswap_16(x)
204 #define SWAP_BE32(x) bswap_32(x)
205 #define SWAP_BE64(x) bswap_64(x)
206 #define SWAP_LE16(x) (x)
207 #define SWAP_LE32(x) (x)
208 #define SWAP_LE64(x) (x)
209 #endif
210
211 #if defined(__APPLE__) \
212 || (defined(__GLIBC__) && __GLIBC__ == 2 && __GLIBC_MINOR__ < 10)
213 ssize_t getdelim(char **lineptr, size_t *n, int delim, FILE *stream);
214 ssize_t getline(char **lineptr, size_t *n, FILE *stream);
215 #endif
216
217 // Linux headers not listed by POSIX or LSB
218 #include <sys/mount.h>
219 #include <sys/swap.h>
220
221 // Android is missing some headers and functions
222 // "generated/config.h" is included first
223 #if CFG_TOYBOX_SHADOW
224 #include <shadow.h>
225 #endif
226 #if CFG_TOYBOX_UTMPX
227 #include <utmpx.h>
228 #else
229 struct utmpx {int ut_type;};
230 #define USER_PROCESS 0
getutxent(void)231 static inline struct utmpx *getutxent(void) {return 0;}
setutxent(void)232 static inline void setutxent(void) {;}
endutxent(void)233 static inline void endutxent(void) {;}
234 #endif
235
236 // Some systems don't define O_NOFOLLOW, and it varies by architecture, so...
237 #include <fcntl.h>
238 #ifndef O_NOFOLLOW
239 #define O_NOFOLLOW 0
240 #endif
241
242 #ifndef O_NOATIME
243 #define O_NOATIME 01000000
244 #endif
245
246 #ifndef O_CLOEXEC
247 #define O_CLOEXEC 02000000
248 #endif
249
250 #ifndef O_PATH
251 #define O_PATH 010000000
252 #endif
253
254 // Glibc won't give you linux-kernel constants unless you say "no, a BUD lite"
255 // even though linux has nothing to do with the FSF and never has.
256 #ifndef F_SETPIPE_SZ
257 #define F_SETPIPE_SZ 1031
258 #endif
259
260 #ifndef F_GETPIPE_SZ
261 #define F_GETPIPE_SZ 1032
262 #endif
263
264 #if defined(__SIZEOF_DOUBLE__) && defined(__SIZEOF_LONG__) \
265 && __SIZEOF_DOUBLE__ <= __SIZEOF_LONG__
266 typedef double FLOAT;
267 #else
268 typedef float FLOAT;
269 #endif
270
271 #ifndef __uClinux__
272 pid_t xfork(void);
273 #endif
274
275 //#define strncpy(...) @@strncpyisbadmmkay@@
276 //#define strncat(...) @@strncatisbadmmkay@@
277
278