-#serial 3
+# Detect some bugs in glibc's implementation of utimes.
+# serial 3
-dnl Shamelessly cloned from acspecific.m4's AC_FUNC_UTIME_NULL,
-dnl then do case-insensitive s/utime/utimes/.
+dnl Copyright (C) 2003-2005, 2009-2014 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.
-AC_DEFUN(jm_FUNC_UTIMES_NULL,
-[AC_CACHE_CHECK(whether utimes accepts a null argument, ac_cv_func_utimes_null,
-[rm -f conftest.data; > conftest.data
-AC_TRY_RUN([
-/* In case stat has been defined to rpl_stat, undef it here. */
-#undef stat
+# 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.
+
+AC_DEFUN([gl_FUNC_UTIMES],
+[
+ AC_CACHE_CHECK([whether the utimes function works],
+ [gl_cv_func_working_utimes],
+ [
+ AC_RUN_IFELSE([AC_LANG_SOURCE([[
#include <sys/types.h>
#include <sys/stat.h>
-main() {
-struct stat s, t;
-exit(!(stat ("conftest.data", &s) == 0
- && utimes("conftest.data", (long *)0) == 0
- && stat("conftest.data", &t) == 0
- && t.st_mtime >= s.st_mtime
- && t.st_mtime - s.st_mtime < 120));
-}],
- ac_cv_func_utimes_null=yes,
- ac_cv_func_utimes_null=no,
- ac_cv_func_utimes_null=no)
-rm -f core core.* *.core])
-
- if test $ac_cv_func_utimes_null = yes; then
- AC_DEFINE_UNQUOTED(HAVE_UTIMES_NULL, 1,
- [Define if utimes accepts a null argument])
- fi
- ]
-)
+#include <fcntl.h>
+#include <sys/time.h>
+#include <time.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <utime.h>
+
+static int
+inorder (time_t a, time_t b, time_t c)
+{
+ return a <= b && b <= c;
+}
+
+int
+main ()
+{
+ int result = 0;
+ char const *file = "conftest.utimes";
+ static struct timeval timeval[2] = {{9, 10}, {999999, 999999}};
+
+ /* Test whether utimes() essentially works. */
+ {
+ struct stat sbuf;
+ FILE *f = fopen (file, "w");
+ if (f == NULL)
+ result |= 1;
+ else if (fclose (f) != 0)
+ result |= 1;
+ else if (utimes (file, timeval) != 0)
+ result |= 2;
+ else if (lstat (file, &sbuf) != 0)
+ result |= 1;
+ else if (!(sbuf.st_atime == timeval[0].tv_sec
+ && sbuf.st_mtime == timeval[1].tv_sec))
+ result |= 4;
+ if (unlink (file) != 0)
+ result |= 1;
+ }
+
+ /* Test whether utimes() with a NULL argument sets the file's timestamp
+ to the current time. Use 'fstat' as well as 'time' to
+ determine the "current" time, to accommodate NFS file systems
+ if there is a time skew between the host and the NFS server. */
+ {
+ int fd = open (file, O_WRONLY|O_CREAT, 0644);
+ if (fd < 0)
+ result |= 1;
+ else
+ {
+ time_t t0, t2;
+ struct stat st0, st1, st2;
+ if (time (&t0) == (time_t) -1)
+ result |= 1;
+ else if (fstat (fd, &st0) != 0)
+ result |= 1;
+ else if (utimes (file, timeval) != 0)
+ result |= 2;
+ else if (utimes (file, NULL) != 0)
+ result |= 8;
+ else if (fstat (fd, &st1) != 0)
+ result |= 1;
+ else if (write (fd, "\n", 1) != 1)
+ result |= 1;
+ else if (fstat (fd, &st2) != 0)
+ result |= 1;
+ else if (time (&t2) == (time_t) -1)
+ result |= 1;
+ else
+ {
+ int m_ok_POSIX = inorder (t0, st1.st_mtime, t2);
+ int m_ok_NFS = inorder (st0.st_mtime, st1.st_mtime, st2.st_mtime);
+ if (! (st1.st_atime == st1.st_mtime))
+ result |= 16;
+ if (! (m_ok_POSIX || m_ok_NFS))
+ result |= 32;
+ }
+ if (close (fd) != 0)
+ result |= 1;
+ }
+ if (unlink (file) != 0)
+ result |= 1;
+ }
+
+ /* Test whether utimes() with a NULL argument works on read-only files. */
+ {
+ int fd = open (file, O_WRONLY|O_CREAT, 0444);
+ if (fd < 0)
+ result |= 1;
+ else if (close (fd) != 0)
+ result |= 1;
+ else if (utimes (file, NULL) != 0)
+ result |= 64;
+ if (unlink (file) != 0)
+ result |= 1;
+ }
+
+ return result;
+}
+ ]])],
+ [gl_cv_func_working_utimes=yes],
+ [gl_cv_func_working_utimes=no],
+ [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. ])
+ fi
+])
projects / gnulib.git / blobdiff