// Workarounds for horrible build environment idiosyncrasies. // Instead of polluting the code with strange #ifdefs to work around bugs // in specific compiler, library, or OS versions, localize all that here // and in portability.c // The tendency of gcc to produce stupid warnings continues with // warn_unused_result, which warns about things like ignoring the return code // of nice(2) (which is completely useless since -1 is a legitimate return // value on success and even the man page tells you to use errno instead). // This makes it stop. #undef _FORTIFY_SOURCE // For musl #define _ALL_SOURCE // Test for gcc (using compiler builtin #define) #ifdef __GNUC__ #define noreturn __attribute__((noreturn)) #else #define noreturn #endif // Always use long file support. #define _FILE_OFFSET_BITS 64 // This isn't in the spec, but it's how we determine what libc we're using. #include <features.h> // Various constants old build environments might not have even if kernel does #ifndef AT_FDCWD #define AT_FDCWD -100 #endif #ifndef AT_SYMLINK_NOFOLLOW #define AT_SYMLINK_NOFOLLOW 0x100 #endif #ifndef AT_REMOVEDIR #define AT_REMOVEDIR 0x200 #endif // We don't define GNU_dammit because we're not part of the gnu project, and // don't want to get any FSF on us. Unfortunately glibc (gnu libc) // won't give us Linux syscall wrappers without claiming to be part of the // gnu project (because Stallman's "GNU owns Linux" revisionist history // crusade includes the kernel, even though Linux was inspired by Minix). // We use most non-posix Linux syscalls directly through the syscall() wrapper, // but even many posix-2008 functions aren't provided by glibc unless you // claim it's in the name of Gnu. #if defined(__GLIBC__) // "Function prototypes shall be provided." but aren't. // http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/unistd.h.html char *crypt(const char *key, const char *salt); // see http://pubs.opengroup.org/onlinepubs/9699919799/functions/strptime.html #include <time.h> char *strptime(const char *buf, const char *format, struct tm *tm); // uClibc pretends to be glibc and copied a lot of its bugs, but has a few more #if defined(__UCLIBC__) #include <unistd.h> #include <stdio.h> ssize_t getdelim(char **lineptr, size_t *n, int delim, FILE *stream); // When building under obsolete glibc (Ubuntu 8.04-ish), hold its hand a bit. #elif __GLIBC__ == 2 && __GLIBC_MINOR__ < 10 #define fstatat fstatat64 int fstatat64(int dirfd, const char *pathname, void *buf, int flags); int readlinkat(int dirfd, const char *pathname, char *buf, size_t bufsiz); char *stpcpy(char *dest, const char *src); #include <sys/stat.h> int fchmodat(int dirfd, const char *pathname, mode_t mode, int flags); int openat(int dirfd, const char *pathname, int flags, ...); #include <dirent.h> DIR *fdopendir(int fd); #include <unistd.h> int fchownat(int dirfd, const char *pathname, uid_t owner, gid_t group, int flags); int isblank(int c); int unlinkat(int dirfd, const char *pathname, int flags); #include <stdio.h> ssize_t getdelim(char **lineptr, size_t *n, int delim, FILE *stream); // Straight from posix-2008, things old glibc had but didn't prototype int faccessat(int fd, const char *path, int amode, int flag); int linkat(int fd1, const char *path1, int fd2, const char *path2, int flag); int mkdirat(int fd, const char *path, mode_t mode); int symlinkat(const char *path1, int fd, const char *path2); int mknodat(int fd, const char *path, mode_t mode, dev_t dev); #include <sys/time.h> int futimens(int fd, const struct timespec times[2]); int utimensat(int fd, const char *path, const struct timespec times[2], int flag); #ifndef MNT_DETACH #define MNT_DETACH 2 #endif #endif #endif // Work out how to do endianness #ifndef __APPLE__ #include <byteswap.h> #include <endian.h> #if __BYTE_ORDER == __BIG_ENDIAN #define IS_BIG_ENDIAN 1 #else #define IS_BIG_ENDIAN 0 #endif int clearenv(void); #else #ifdef __BIG_ENDIAN__ #define IS_BIG_ENDIAN 1 #else #define IS_BIG_ENDIAN 0 #endif #endif #if IS_BIG_ENDIAN #define IS_LITTLE_ENDIAN 0 #define SWAP_BE16(x) (x) #define SWAP_BE32(x) (x) #define SWAP_BE64(x) (x) #define SWAP_LE16(x) bswap_16(x) #define SWAP_LE32(x) bswap_32(x) #define SWAP_LE64(x) bswap_64(x) #else #define IS_LITTLE_ENDIAN 1 #define SWAP_BE16(x) bswap_16(x) #define SWAP_BE32(x) bswap_32(x) #define SWAP_BE64(x) bswap_64(x) #define SWAP_LE16(x) (x) #define SWAP_LE32(x) (x) #define SWAP_LE64(x) (x) #endif #if defined(__APPLE__) || defined(__ANDROID__) \ || (defined(__GLIBC__) && __GLIBC__ == 2 && __GLIBC_MINOR__ < 10) ssize_t getdelim(char **lineptr, size_t *n, int delim, FILE *stream); ssize_t getline(char **lineptr, size_t *n, FILE *stream); #endif // Linux headers not listed by POSIX or LSB #include <shadow.h> #include <sys/mount.h> #include <sys/swap.h> // Some systems don't define O_NOFOLLOW, and it varies by architecture, so... #include <fcntl.h> #ifndef O_NOFOLLOW #define O_NOFOLLOW 0 #endif #if defined(__SIZEOF_DOUBLE__) && defined(__SIZEOF_LONG__) \ && __SIZEOF_DOUBLE__ <= __SIZEOF_LONG__ typedef double FLOAT; #else typedef float FLOAT; #endif