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[gnulib.git] / m4 / utimes.m4

diff --git a/m4/utimes.m4 b/m4/utimes.m4
index dae46f0..5b010ac 100644 (file)
--- a/m4/utimes.m4
+++ b/m4/utimes.m4
@@ -1,8 +1,19 @@
+# Detect some bugs in glibc's implementation of utimes.
+
+dnl Copyright (C) 2003, 2004, 2005, 2009 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.
+
 # See if we need to work around bugs in glibc's implementation of
 # utimes from 2003-07-12 to 2003-09-17.
 # First, there was a bug that would make utimes set mtime
 # and atime to zero (1970-01-01) unconditionally.
 # Then, there was code to round rather than truncate.
+# Then, there was an implementation (sparc64, Linux-2.4.28, glibc-2.3.3)
+# that didn't honor the NULL-means-set-to-current-time semantics.
+# Finally, there was also a version of utimes that failed on read-only
+# files, while utime worked fine (linux-2.2.20, glibc-2.2.5).
 #
 # From Jim Meyering, with suggestions from Paul Eggert.
 
@@ -14,7 +25,9 @@ AC_DEFUN([gl_FUNC_UTIMES],
   AC_RUN_IFELSE([AC_LANG_SOURCE([[
 #include <sys/types.h>
 #include <sys/stat.h>
+#include <fcntl.h>
 #include <sys/time.h>
+#include <time.h>
 #include <unistd.h>
 #include <stdlib.h>
 #include <stdio.h>
@@ -27,13 +40,37 @@ main ()
   struct stat sbuf;
   char const *file = "conftest.utimes";
   FILE *f;
+  time_t now;
+  int fd;
 
-  exit ( ! ((f = fopen (file, "w"))
+  int ok = ((f = fopen (file, "w"))
            && fclose (f) == 0
            && utimes (file, timeval) == 0
            && lstat (file, &sbuf) == 0
            && sbuf.st_atime == timeval[0].tv_sec
-           && sbuf.st_mtime == timeval[1].tv_sec) );
+           && sbuf.st_mtime == timeval[1].tv_sec);
+  unlink (file);
+  if (!ok)
+    exit (1);
+
+  ok =
+    ((f = fopen (file, "w"))
+     && fclose (f) == 0
+     && time (&now) != (time_t)-1
+     && utimes (file, NULL) == 0
+     && lstat (file, &sbuf) == 0
+     && now - sbuf.st_atime <= 2
+     && now - sbuf.st_mtime <= 2);
+  unlink (file);
+  if (!ok)
+    exit (1);
+
+  ok = (0 <= (fd = open (file, O_WRONLY|O_CREAT, 0444))
+             && close (fd) == 0
+             && utimes (file, NULL) == 0);
+  unlink (file);
+
+  exit (!ok);
 }
   ]])],
        [gl_cv_func_working_utimes=yes],
@@ -41,6 +78,6 @@ main ()
        [gl_cv_func_working_utimes=no])])
 
   if test $gl_cv_func_working_utimes = yes; then
-    AC_DEFINE([HAVE_WORKING_UTIMES], 1, [Define if utimes works properly. ])
+    AC_DEFINE([HAVE_WORKING_UTIMES], [1], [Define if utimes works properly. ])
   fi
 ])