diff options
Diffstat (limited to 'gnulib-m4/fcntl-o.m4')
-rw-r--r-- | gnulib-m4/fcntl-o.m4 | 95 |
1 files changed, 74 insertions, 21 deletions
diff --git a/gnulib-m4/fcntl-o.m4 b/gnulib-m4/fcntl-o.m4 index d416a61c..891a62fb 100644 --- a/gnulib-m4/fcntl-o.m4 +++ b/gnulib-m4/fcntl-o.m4 @@ -1,5 +1,5 @@ -# fcntl-o.m4 serial 1 -dnl Copyright (C) 2006, 2009-2010 Free Software Foundation, Inc. +# fcntl-o.m4 serial 4 +dnl Copyright (C) 2006, 2009-2015 Free Software Foundation, Inc. dnl This file is free software; the Free Software Foundation dnl gives unlimited permission to copy and/or distribute it, dnl with or without modifications, as long as this notice is preserved. @@ -12,13 +12,26 @@ dnl Written by Paul Eggert. AC_DEFUN([gl_FCNTL_O_FLAGS], [ dnl Persuade glibc <fcntl.h> to define O_NOATIME and O_NOFOLLOW. - AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS]) + dnl AC_USE_SYSTEM_EXTENSIONS was introduced in autoconf 2.60 and obsoletes + dnl AC_GNU_SOURCE. + m4_ifdef([AC_USE_SYSTEM_EXTENSIONS], + [AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])], + [AC_REQUIRE([AC_GNU_SOURCE])]) + + AC_CHECK_HEADERS_ONCE([unistd.h]) + AC_CHECK_FUNCS_ONCE([symlink]) AC_CACHE_CHECK([for working fcntl.h], [gl_cv_header_working_fcntl_h], [AC_RUN_IFELSE( [AC_LANG_PROGRAM( [[#include <sys/types.h> #include <sys/stat.h> - #include <unistd.h> + #if HAVE_UNISTD_H + # include <unistd.h> + #else /* on Windows with MSVC */ + # include <io.h> + # include <stdlib.h> + # defined sleep(n) _sleep ((n) * 1000) + #endif #include <fcntl.h> #ifndef O_NOATIME #define O_NOATIME 0 @@ -33,34 +46,74 @@ AC_DEFUN([gl_FCNTL_O_FLAGS], }; ]], [[ - int status = !constants; + int result = !constants; + #if HAVE_SYMLINK { static char const sym[] = "conftest.sym"; - if (symlink (".", sym) != 0 - || close (open (sym, O_RDONLY | O_NOFOLLOW)) == 0) - status |= 32; + if (symlink ("/dev/null", sym) != 0) + result |= 2; + else + { + int fd = open (sym, O_WRONLY | O_NOFOLLOW | O_CREAT, 0); + if (fd >= 0) + { + close (fd); + result |= 4; + } + } + if (unlink (sym) != 0 || symlink (".", sym) != 0) + result |= 2; + else + { + int fd = open (sym, O_RDONLY | O_NOFOLLOW); + if (fd >= 0) + { + close (fd); + result |= 4; + } + } unlink (sym); } + #endif { static char const file[] = "confdefs.h"; int fd = open (file, O_RDONLY | O_NOATIME); - char c; - struct stat st0, st1; - if (fd < 0 - || fstat (fd, &st0) != 0 - || sleep (1) != 0 - || read (fd, &c, 1) != 1 - || close (fd) != 0 - || stat (file, &st1) != 0 - || st0.st_atime != st1.st_atime) - status |= 64; + if (fd < 0) + result |= 8; + else + { + struct stat st0; + if (fstat (fd, &st0) != 0) + result |= 16; + else + { + char c; + sleep (1); + if (read (fd, &c, 1) != 1) + result |= 24; + else + { + if (close (fd) != 0) + result |= 32; + else + { + struct stat st1; + if (stat (file, &st1) != 0) + result |= 40; + else + if (st0.st_atime != st1.st_atime) + result |= 64; + } + } + } + } } - return status;]])], + return result;]])], [gl_cv_header_working_fcntl_h=yes], [case $? in #( - 32) gl_cv_header_working_fcntl_h='no (bad O_NOFOLLOW)';; #( + 4) gl_cv_header_working_fcntl_h='no (bad O_NOFOLLOW)';; #( 64) gl_cv_header_working_fcntl_h='no (bad O_NOATIME)';; #( - 96) gl_cv_header_working_fcntl_h='no (bad O_NOATIME, O_NOFOLLOW)';; #( + 68) gl_cv_header_working_fcntl_h='no (bad O_NOATIME, O_NOFOLLOW)';; #( *) gl_cv_header_working_fcntl_h='no';; esac], [gl_cv_header_working_fcntl_h=cross-compiling])]) |