1 // Workarounds for horrible build environment idiosyncrasies.
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
10 // Test for gcc (using compiler builtin #define)
13 #define noreturn __attribute__((noreturn))
18 // Always use long file support.
19 #define _FILE_OFFSET_BITS 64
21 // This isn't in the spec, but it's how we determine what libc we're using.
25 // Various constants old build environments might not have even if kernel does
31 #ifndef AT_SYMLINK_NOFOLLOW
32 #define AT_SYMLINK_NOFOLLOW 0x100
36 #define AT_REMOVEDIR 0x200
39 // We don't define GNU_dammit because we're not part of the gnu project, and
40 // don't want to get any FSF on us. Unfortunately glibc (gnu libc)
41 // won't give us Linux syscall wrappers without claiming to be part of the
42 // gnu project (because Stallman's "GNU owns Linux" revisionist history
43 // crusade includes the kernel, even though Linux was inspired by Minix).
45 // We use most non-posix Linux syscalls directly through the syscall() wrapper,
46 // but even many posix-2008 functions aren't provided by glibc unless you
47 // claim it's in the name of Gnu.
49 #if defined(__GLIBC__)
50 // "Function prototypes shall be provided." but aren't.
51 // http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/unistd.h.html
52 char *crypt(const char *key, const char *salt);
54 // According to posix, #include header, get a function definition. But glibc...
55 // http://pubs.opengroup.org/onlinepubs/9699919799/functions/wcwidth.html
57 int wcwidth(wchar_t wc);
59 // see http://pubs.opengroup.org/onlinepubs/9699919799/functions/strptime.html
61 char *strptime(const char *buf, const char *format, struct tm *tm);
63 // They didn't like posix basename so they defined another function with the
64 // same name and if you include libgen.h it #defines basename to something
65 // else (where they implemented the real basename), and that define breaks
66 // the table entry for the basename command. They didn't make a new function
67 // with a different name for their new behavior because gnu.
69 // Solution: don't use their broken header, provide an inline to redirect the
70 // correct name to the broken name.
72 char *dirname(char *path);
73 char *__xpg_basename (char *path);
74 static inline char *basename(char *path) { return __xpg_basename(path); }
76 // uClibc pretends to be glibc and copied a lot of its bugs, but has a few more
77 #if defined(__UCLIBC__)
80 ssize_t getdelim(char **lineptr, size_t *n, int delim, FILE *stream);
81 char *stpcpy(char *dest, const char *src);
82 pid_t getsid(pid_t pid);
84 // uClibc's last-ever release was in 2012, so of course it doesn't define
85 // any flag newer than MS_MOVE, which was added in 2001 (linux 2.5.0.5),
86 // eleven years earlier.
88 #include <sys/mount.h>
90 #define MS_MOVE (1<<13)
93 #define MS_REC (1<<14)
96 #define MS_SILENT (1<<15)
99 #define MS_UNBINDABLE (1<<17)
102 #define MS_PRIVATE (1<<18)
105 #define MS_SLAVE (1<<19)
108 #define MS_SHARED (1<<20)
111 // When building under obsolete glibc (Ubuntu 8.04-ish), hold its hand a bit.
112 #elif __GLIBC__ == 2 && __GLIBC_MINOR__ < 10
113 #define fstatat fstatat64
114 int fstatat64(int dirfd, const char *pathname, void *buf, int flags);
115 int readlinkat(int dirfd, const char *pathname, char *buf, size_t bufsiz);
116 char *stpcpy(char *dest, const char *src);
117 #include <sys/stat.h>
118 int fchmodat(int dirfd, const char *pathname, mode_t mode, int flags);
119 int openat(int dirfd, const char *pathname, int flags, ...);
121 DIR *fdopendir(int fd);
123 int fchownat(int dirfd, const char *pathname,
124 uid_t owner, gid_t group, int flags);
126 int unlinkat(int dirfd, const char *pathname, int flags);
128 ssize_t getdelim(char **lineptr, size_t *n, int delim, FILE *stream);
130 // Straight from posix-2008, things old glibc had but didn't prototype
132 int faccessat(int fd, const char *path, int amode, int flag);
133 int linkat(int fd1, const char *path1, int fd2, const char *path2, int flag);
134 int mkdirat(int fd, const char *path, mode_t mode);
135 int symlinkat(const char *path1, int fd, const char *path2);
136 int mknodat(int fd, const char *path, mode_t mode, dev_t dev);
137 #include <sys/time.h>
138 int futimens(int fd, const struct timespec times[2]);
139 int utimensat(int fd, const char *path, const struct timespec times[2], int flag);
146 #endif // glibc in general
155 // Without this "rm -r dir" fails with "is directory".
156 #define faccessat(A, B, C, D) faccessat(A, B, C, 0)
159 // Work out how to do endianness
162 #include <byteswap.h>
165 #if __BYTE_ORDER == __BIG_ENDIAN
166 #define IS_BIG_ENDIAN 1
168 #define IS_BIG_ENDIAN 0
174 #ifdef __BIG_ENDIAN__
175 #define IS_BIG_ENDIAN 1
177 #define IS_BIG_ENDIAN 0
183 #define IS_LITTLE_ENDIAN 0
184 #define SWAP_BE16(x) (x)
185 #define SWAP_BE32(x) (x)
186 #define SWAP_BE64(x) (x)
187 #define SWAP_LE16(x) bswap_16(x)
188 #define SWAP_LE32(x) bswap_32(x)
189 #define SWAP_LE64(x) bswap_64(x)
191 #define IS_LITTLE_ENDIAN 1
192 #define SWAP_BE16(x) bswap_16(x)
193 #define SWAP_BE32(x) bswap_32(x)
194 #define SWAP_BE64(x) bswap_64(x)
195 #define SWAP_LE16(x) (x)
196 #define SWAP_LE32(x) (x)
197 #define SWAP_LE64(x) (x)
200 #if defined(__APPLE__) \
201 || (defined(__GLIBC__) && __GLIBC__ == 2 && __GLIBC_MINOR__ < 10)
202 ssize_t getdelim(char **lineptr, size_t *n, int delim, FILE *stream);
203 ssize_t getline(char **lineptr, size_t *n, FILE *stream);
206 // Linux headers not listed by POSIX or LSB
207 #include <sys/mount.h>
208 #include <sys/swap.h>
210 // Android is missing some headers and functions
211 // "generated/config.h" is included first
212 #if CFG_TOYBOX_SHADOW
219 // Some systems don't define O_NOFOLLOW, and it varies by architecture, so...
226 #define O_CLOEXEC 02000000
229 #if defined(__SIZEOF_DOUBLE__) && defined(__SIZEOF_LONG__) \
230 && __SIZEOF_DOUBLE__ <= __SIZEOF_LONG__
231 typedef double FLOAT;
240 //#define strncpy(...) @@strncpyisbadmmkay@@
241 //#define strncat(...) @@strcatisbadmmkay@@
243 #if CFG_TOYBOX_SELINUX
244 #include <selinux/selinux.h>
246 #define is_selinux_enabled() 0
247 int getcon(void* con);