Sync with gnulib.

1 files changed, 12 insertions, 37 deletions

diff --git a/m4/chown.m4 b/m4/chown.m4
index 1f3f51b46..86c5fc754 100644
--- a/m4/chown.m4
+++ b/m4/chown.m4
@@ -1,4 +1,4 @@
-#serial 7
+#serial 8
 
 dnl From Jim Meyering.
 dnl Determine whether chown accepts arguments of -1 for uid and gid.
@@ -6,44 +6,19 @@ dnl If it doesn't, arrange to use the replacement function.
 dnl
 
 AC_DEFUN([jm_FUNC_CHOWN],
-[AC_REQUIRE([AC_TYPE_UID_T])dnl
- test -z "$ac_cv_header_unistd_h" \
-   && AC_CHECK_HEADERS(unistd.h)
- AC_CACHE_CHECK([for working chown], jm_cv_func_working_chown,
-  [AC_TRY_RUN([
-#   include <sys/types.h>
-#   include <sys/stat.h>
-#   include <fcntl.h>
-#   ifdef HAVE_UNISTD_H
-#    include <unistd.h>
-#   endif
-
-    int
-    main ()
-    {
-      char *f = "conftest.chown";
-      struct stat before, after;
-
-      if (creat (f, 0600) < 0)
-        exit (1);
-      if (stat (f, &before) < 0)
-        exit (1);
-      if (chown (f, (uid_t) -1, (gid_t) -1) == -1)
-        exit (1);
-      if (stat (f, &after) < 0)
-        exit (1);
-      exit ((before.st_uid == after.st_uid
-	     && before.st_gid == after.st_gid) ? 0 : 1);
-    }
-	      ],
-	     jm_cv_func_working_chown=yes,
-	     jm_cv_func_working_chown=no,
-	     dnl When crosscompiling, assume chown is broken.
-	     jm_cv_func_working_chown=no)
-  ])
-  if test $jm_cv_func_working_chown = no; then
+[
+  AC_REQUIRE([AC_TYPE_UID_T])dnl
+  AC_REQUIRE([AC_FUNC_CHOWN])
+  if test $ac_cv_func_chown_works = no; then
     AC_LIBOBJ(chown)
     AC_DEFINE(chown, rpl_chown,
       [Define to rpl_chown if the replacement function should be used.])
+    gl_PREREQ_CHOWN
   fi
 ])
+
+# Prerequisites of lib/chown.c.
+AC_DEFUN([gl_PREREQ_CHOWN],
+[
+  AC_CHECK_HEADERS_ONCE(unistd.h)
+])