From 9559c2c4a0e99975782fa283c77f5a22a50e1bff Mon Sep 17 00:00:00 2001 From: Rob Landley Date: Sun, 24 Feb 2013 11:11:02 -0600 Subject: Comment updates and a policy statement about avoiding #define GNU_dammit --- lib/portability.h | 34 +++++++++++++++++++++++----------- 1 file changed, 23 insertions(+), 11 deletions(-) (limited to 'lib') diff --git a/lib/portability.h b/lib/portability.h index c85ad04a..d0726b95 100644 --- a/lib/portability.h +++ b/lib/portability.h @@ -1,4 +1,5 @@ // 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 @@ -12,10 +13,18 @@ #undef _FORTIFY_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 we're using. +// This isn't in the spec, but it's how we determine what libc we're using. #include @@ -41,12 +50,21 @@ #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); -// An SUSv4 function that glibc refuses to #define without crazy #defines, // see http://pubs.opengroup.org/onlinepubs/9699919799/functions/strptime.html #include char *strptime(const char *buf, const char *format, struct tm *tm); @@ -57,7 +75,7 @@ char *strptime(const char *buf, const char *format, struct tm *tm); #include ssize_t getdelim(char **lineptr, size_t *n, int delim, FILE *stream); -// When building under obsolete glibc, hold its hand a bit. +// 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); @@ -76,7 +94,7 @@ int unlinkat(int dirfd, const char *pathname, int flags); #include ssize_t getdelim(char **lineptr, size_t *n, int delim, FILE *stream); -// Straight from posix-2008, things old glibc didn't define +// 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); @@ -90,13 +108,7 @@ int utimensat(int fd, const char *path, const struct timespec times[2], int flag #endif -// Test for gcc - -#ifdef __GNUC__ -#define noreturn __attribute__((noreturn)) -#else -#define noreturn -#endif +// Work out how to do endianness #ifndef __APPLE__ #include -- cgit v1.2.3