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))
14 #define printf_format __attribute__((format(printf, 1, 2)))
20 // Always use long file support.
21 #define _FILE_OFFSET_BITS 64
23 // This isn't in the spec, but it's how we determine what libc we're using.
27 // Various constants old build environments might not have even if kernel does
33 #ifndef AT_SYMLINK_NOFOLLOW
34 #define AT_SYMLINK_NOFOLLOW 0x100
38 #define AT_REMOVEDIR 0x200
41 // We don't define GNU_dammit because we're not part of the gnu project, and
42 // don't want to get any FSF on us. Unfortunately glibc (gnu libc)
43 // won't give us Linux syscall wrappers without claiming to be part of the
44 // gnu project (because Stallman's "GNU owns Linux" revisionist history
45 // crusade includes the kernel, even though Linux was inspired by Minix).
47 // We use most non-posix Linux syscalls directly through the syscall() wrapper,
48 // but even many posix-2008 functions aren't provided by glibc unless you
49 // claim it's in the name of Gnu.
51 #if defined(__GLIBC__)
52 // "Function prototypes shall be provided." but aren't.
53 // http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/unistd.h.html
54 char *crypt(const char *key, const char *salt);
56 // According to posix, #include header, get a function definition. But glibc...
57 // http://pubs.opengroup.org/onlinepubs/9699919799/functions/wcwidth.html
59 int wcwidth(wchar_t wc);
61 // see http://pubs.opengroup.org/onlinepubs/9699919799/functions/strptime.html
63 char *strptime(const char *buf, const char *format, struct tm *tm);
65 // They didn't like posix basename so they defined another function with the
66 // same name and if you include libgen.h it #defines basename to something
67 // else (where they implemented the real basename), and that define breaks
68 // the table entry for the basename command. They didn't make a new function
69 // with a different name for their new behavior because gnu.
71 // Solution: don't use their broken header, provide an inline to redirect the
72 // correct name to the broken name.
74 char *dirname(char *path);
75 char *__xpg_basename (char *path);
76 static inline char *basename(char *path) { return __xpg_basename(path); }
78 // uClibc pretends to be glibc and copied a lot of its bugs, but has a few more
79 #if defined(__UCLIBC__)
82 ssize_t getdelim(char **lineptr, size_t *n, int delim, FILE *stream);
83 char *stpcpy(char *dest, const char *src);
84 pid_t getsid(pid_t pid);
86 // uClibc's last-ever release was in 2012, so of course it doesn't define
87 // any flag newer than MS_MOVE, which was added in 2001 (linux 2.5.0.5),
88 // eleven years earlier.
90 #include <sys/mount.h>
92 #define MS_MOVE (1<<13)
95 #define MS_REC (1<<14)
98 #define MS_SILENT (1<<15)
100 #ifndef MS_UNBINDABLE
101 #define MS_UNBINDABLE (1<<17)
104 #define MS_PRIVATE (1<<18)
107 #define MS_SLAVE (1<<19)
110 #define MS_SHARED (1<<20)
113 // When building under obsolete glibc (Ubuntu 8.04-ish), hold its hand a bit.
114 #elif __GLIBC__ == 2 && __GLIBC_MINOR__ < 10
115 #define fstatat fstatat64
116 int fstatat64(int dirfd, const char *pathname, void *buf, int flags);
117 int readlinkat(int dirfd, const char *pathname, char *buf, size_t bufsiz);
118 char *stpcpy(char *dest, const char *src);
119 #include <sys/stat.h>
120 int fchmodat(int dirfd, const char *pathname, mode_t mode, int flags);
121 int openat(int dirfd, const char *pathname, int flags, ...);
123 DIR *fdopendir(int fd);
125 int fchownat(int dirfd, const char *pathname,
126 uid_t owner, gid_t group, int flags);
128 int unlinkat(int dirfd, const char *pathname, int flags);
130 ssize_t getdelim(char **lineptr, size_t *n, int delim, FILE *stream);
132 // Straight from posix-2008, things old glibc had but didn't prototype
134 int faccessat(int fd, const char *path, int amode, int flag);
135 int linkat(int fd1, const char *path1, int fd2, const char *path2, int flag);
136 int mkdirat(int fd, const char *path, mode_t mode);
137 int symlinkat(const char *path1, int fd, const char *path2);
138 int mknodat(int fd, const char *path, mode_t mode, dev_t dev);
139 #include <sys/time.h>
140 int futimens(int fd, const struct timespec times[2]);
141 int utimensat(int fd, const char *path, const struct timespec times[2], int flag);
148 #endif // glibc in general
155 // Work out how to do endianness
158 #include <byteswap.h>
161 #if __BYTE_ORDER == __BIG_ENDIAN
162 #define IS_BIG_ENDIAN 1
164 #define IS_BIG_ENDIAN 0
170 #ifdef __BIG_ENDIAN__
171 #define IS_BIG_ENDIAN 1
173 #define IS_BIG_ENDIAN 0
179 #define IS_LITTLE_ENDIAN 0
180 #define SWAP_BE16(x) (x)
181 #define SWAP_BE32(x) (x)
182 #define SWAP_BE64(x) (x)
183 #define SWAP_LE16(x) bswap_16(x)
184 #define SWAP_LE32(x) bswap_32(x)
185 #define SWAP_LE64(x) bswap_64(x)
187 #define IS_LITTLE_ENDIAN 1
188 #define SWAP_BE16(x) bswap_16(x)
189 #define SWAP_BE32(x) bswap_32(x)
190 #define SWAP_BE64(x) bswap_64(x)
191 #define SWAP_LE16(x) (x)
192 #define SWAP_LE32(x) (x)
193 #define SWAP_LE64(x) (x)
196 #if defined(__APPLE__) \
197 || (defined(__GLIBC__) && __GLIBC__ == 2 && __GLIBC_MINOR__ < 10)
198 ssize_t getdelim(char **lineptr, size_t *n, int delim, FILE *stream);
199 ssize_t getline(char **lineptr, size_t *n, FILE *stream);
202 // Linux headers not listed by POSIX or LSB
203 #include <sys/mount.h>
204 #include <sys/swap.h>
206 // Android is missing some headers and functions
207 // "generated/config.h" is included first
208 #if CFG_TOYBOX_SHADOW
215 // Some systems don't define O_NOFOLLOW, and it varies by architecture, so...
222 #define O_CLOEXEC 02000000
225 #if defined(__SIZEOF_DOUBLE__) && defined(__SIZEOF_LONG__) \
226 && __SIZEOF_DOUBLE__ <= __SIZEOF_LONG__
227 typedef double FLOAT;
236 //#define strncpy(...) @@strncpyisbadmmkay@@
237 //#define strncat(...) @@strcatisbadmmkay@@
239 #if CFG_TOYBOX_SELINUX
240 #include <selinux/selinux.h>
242 #define is_selinux_enabled() 0
243 int getcon(void* con);