1 # Detect some bugs in glibc's implementation of utimes.
4 dnl Copyright (C) 2003-2005, 2009-2010 Free Software Foundation, Inc.
5 dnl This file is free software; the Free Software Foundation
6 dnl gives unlimited permission to copy and/or distribute it,
7 dnl with or without modifications, as long as this notice is preserved.
9 # See if we need to work around bugs in glibc's implementation of
10 # utimes from 2003-07-12 to 2003-09-17.
11 # First, there was a bug that would make utimes set mtime
12 # and atime to zero (1970-01-01) unconditionally.
13 # Then, there was code to round rather than truncate.
14 # Then, there was an implementation (sparc64, Linux-2.4.28, glibc-2.3.3)
15 # that didn't honor the NULL-means-set-to-current-time semantics.
16 # Finally, there was also a version of utimes that failed on read-only
17 # files, while utime worked fine (linux-2.2.20, glibc-2.2.5).
19 # From Jim Meyering, with suggestions from Paul Eggert.
21 AC_DEFUN([gl_FUNC_UTIMES],
23 AC_CACHE_CHECK([whether the utimes function works],
24 [gl_cv_func_working_utimes],
26 AC_RUN_IFELSE([AC_LANG_SOURCE([[
27 #include <sys/types.h>
38 inorder (time_t a, time_t b, time_t c)
40 return a <= b && b <= c;
47 char const *file = "conftest.utimes";
48 static struct timeval timeval[2] = {{9, 10}, {999999, 999999}};
50 /* Test whether utimes() essentially works. */
53 FILE *f = fopen (file, "w");
56 else if (fclose (f) != 0)
58 else if (utimes (file, timeval) != 0)
60 else if (lstat (file, &sbuf) != 0)
62 else if (!(sbuf.st_atime == timeval[0].tv_sec
63 && sbuf.st_mtime == timeval[1].tv_sec))
65 if (unlink (file) != 0)
69 /* Test whether utimes() with a NULL argument sets the file's timestamp
70 to the current time. Use 'fstat' as well as 'time' to
71 determine the "current" time, to accommodate NFS file systems
72 if there is a time skew between the host and the NFS server. */
74 int fd = open (file, O_WRONLY|O_CREAT, 0644);
80 struct stat st0, st1, st2;
81 if (time (&t0) == (time_t) -1)
83 else if (fstat (fd, &st0) != 0)
85 else if (utimes (file, timeval) != 0)
87 else if (utimes (file, NULL) != 0)
89 else if (fstat (fd, &st1) != 0)
91 else if (write (fd, "\n", 1) != 1)
93 else if (fstat (fd, &st2) != 0)
95 else if (time (&t2) == (time_t) -1)
99 int a_ok_POSIX = inorder (t0, st1.st_atime, t2);
100 int m_ok_POSIX = inorder (t0, st1.st_mtime, t2);
101 int a_ok_NFS = inorder (st0.st_mtime, st1.st_atime, st2.st_mtime);
102 int m_ok_NFS = inorder (st0.st_mtime, st1.st_mtime, st2.st_mtime);
103 if (! ((a_ok_POSIX || a_ok_NFS) && st1.st_atime == st1.st_mtime))
105 if (! (a_ok_POSIX ? m_ok_POSIX : m_ok_NFS))
111 if (unlink (file) != 0)
115 /* Test whether utimes() with a NULL argument works on read-only files. */
117 int fd = open (file, O_WRONLY|O_CREAT, 0444);
120 else if (close (fd) != 0)
122 else if (utimes (file, NULL) != 0)
124 if (unlink (file) != 0)
131 [gl_cv_func_working_utimes=yes],
132 [gl_cv_func_working_utimes=no],
133 [gl_cv_func_working_utimes=no])])
135 if test $gl_cv_func_working_utimes = yes; then
136 AC_DEFINE([HAVE_WORKING_UTIMES], [1], [Define if utimes works properly. ])