fix some lintian whining

[debian/gzip] / m4 / fcntl-o.m4

diff --git a/m4/fcntl-o.m4 b/m4/fcntl-o.m4
index 9862741f3943c38cc2269b8a582c5c4294ddf942..4dc3daa2faf89e664c938a32631a696599e2b215 100644 (file)
--- a/m4/fcntl-o.m4
+++ b/m4/fcntl-o.m4
@@ -1,5 +1,5 @@
-# fcntl-o.m4 serial 4
-dnl Copyright (C) 2006, 2009-2012 Free Software Foundation, Inc.
+# fcntl-o.m4 serial 5
+dnl Copyright (C) 2006, 2009-2018 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.
@@ -18,6 +18,7 @@ AC_DEFUN([gl_FCNTL_O_FLAGS],
     [AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])],
     [AC_REQUIRE([AC_GNU_SOURCE])])
 
+  AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
   AC_CHECK_HEADERS_ONCE([unistd.h])
   AC_CHECK_FUNCS_ONCE([symlink])
   AC_CACHE_CHECK([for working fcntl.h], [gl_cv_header_working_fcntl_h],
@@ -50,7 +51,18 @@ AC_DEFUN([gl_FCNTL_O_FLAGS],
             #if HAVE_SYMLINK
             {
               static char const sym[] = "conftest.sym";
-              if (symlink (".", sym) != 0)
+              if (symlink ("/dev/null", sym) != 0)
+                result |= 2;
+              else
+                {
+                  int fd = open (sym, O_WRONLY | O_NOFOLLOW | O_CREAT, 0);
+                  if (fd >= 0)
+                    {
+                      close (fd);
+                      result |= 4;
+                    }
+                }
+              if (unlink (sym) != 0 || symlink (".", sym) != 0)
                 result |= 2;
               else
                 {
@@ -105,7 +117,13 @@ AC_DEFUN([gl_FCNTL_O_FLAGS],
         68) gl_cv_header_working_fcntl_h='no (bad O_NOATIME, O_NOFOLLOW)';; #(
          *) gl_cv_header_working_fcntl_h='no';;
         esac],
-       [gl_cv_header_working_fcntl_h=cross-compiling])])
+       [case "$host_os" in
+                  # Guess 'no' on native Windows.
+          mingw*) gl_cv_header_working_fcntl_h='no' ;;
+          *)      gl_cv_header_working_fcntl_h=cross-compiling ;;
+        esac
+       ])
+    ])
 
   case $gl_cv_header_working_fcntl_h in #(
   *O_NOATIME* | no | cross-compiling) ac_val=0;; #(