X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=m4%2Ffutimens.m4;h=a159207a21a0580af88213548991f33cb48c4eae;hb=fa1db0dd22768f09a507674a30beb5b8a87bb35f;hp=0547e7ad544e786a038bc517d521635c42c36f61;hpb=959d9cb463d992f9c5cc2fbeb54bf12eee2346f7;p=gnulib.git

diff --git a/m4/futimens.m4 b/m4/futimens.m4
index 0547e7ad5..a159207a2 100644
--- a/m4/futimens.m4
+++ b/m4/futimens.m4
@@ -1,7 +1,7 @@
-# serial 1
+# serial 6
 # See if we need to provide futimens replacement.
 
-dnl Copyright (C) 2009 Free Software Foundation, Inc.
+dnl Copyright (C) 2009-2013 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.
@@ -15,27 +15,45 @@ AC_DEFUN([gl_FUNC_FUTIMENS],
   AC_CHECK_FUNCS_ONCE([futimens])
   if test $ac_cv_func_futimens = no; then
     HAVE_FUTIMENS=0
-    AC_LIBOBJ([futimens])
   else
     AC_CACHE_CHECK([whether futimens works],
       [gl_cv_func_futimens_works],
       [AC_RUN_IFELSE([AC_LANG_PROGRAM([[
 #include <fcntl.h>
 #include <sys/stat.h>
+#include <unistd.h>
+#include <errno.h>
+]], [[struct timespec ts[2] = { { 1, UTIME_OMIT }, { 1, UTIME_NOW } };
+      int fd = creat ("conftest.file", 0600);
+      struct stat st;
+      if (fd < 0) return 1;
+      errno = 0;
+      if (futimens (AT_FDCWD, NULL) == 0) return 2;
+      if (errno != EBADF) return 3;
+      if (futimens (fd, ts)) return 4;
+      sleep (1);
+      ts[0].tv_nsec = UTIME_NOW;
+      ts[1].tv_nsec = UTIME_OMIT;
+      if (futimens (fd, ts)) return 5;
+      if (fstat (fd, &st)) return 6;
+      if (st.st_ctime < st.st_atime) return 7;
+      ]])],
+dnl FIXME: simplify this in 2012, when file system bugs are no longer common
+         [AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
 #ifdef __linux__
-/* The Linux kernel added futimens in 2.6.22, but it had bugs until 2.6.26.
-   Always replace futimens to support older kernels.  */
+/* The Linux kernel added futimens in 2.6.22, but has bugs with UTIME_OMIT
+   in several file systems as recently as 2.6.32.  Always replace futimens
+   to support older kernels.  */
 choke me
 #endif
-]], [[struct timespec ts[2] = { { 1, UTIME_OMIT }, { 1, UTIME_OMIT } };
-      if (futimens (AT_FDCWD, NULL)) return 1;
-      return futimens (open (".", O_RDONLY), ts);]])],
-         [gl_cv_func_futimens_works=yes],
-         [gl_cv_func_futimens_works="needs runtime check"],
-         [gl_cv_func_futimens_works="guessing no"])])
+      ]])],
+           [gl_cv_func_futimens_works=yes],
+           [gl_cv_func_futimens_works="needs runtime check"])],
+         [gl_cv_func_futimens_works=no],
+         [gl_cv_func_futimens_works="guessing no"])
+      rm -f conftest.file])
     if test "$gl_cv_func_futimens_works" != yes; then
       REPLACE_FUTIMENS=1
-      AC_LIBOBJ([futimens])
     fi
   fi
 ])