Manual: improve out-of-memory documentation.

[gnulib.git] / m4 / dos.m4

diff --git a/m4/dos.m4 b/m4/dos.m4
index fc68724..5660542 100644 (file)
--- a/m4/dos.m4
+++ b/m4/dos.m4
@@ -1,24 +1,12 @@
-#serial 7
+#serial 11   -*- autoconf -*-
 
 # Define some macros required for proper operation of code in lib/*.c
 # on MSDOS/Windows systems.
 
-# Copyright (C) 2000, 2001, 2004 Free Software Foundation, Inc.
-
-# This program is free software; you can redistribute it and/or modify
-# it under the terms of the GNU General Public License as published by
-# the Free Software Foundation; either version 2, or (at your option)
-# any later version.
-
-# This program is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU General Public License for more details.
-
-# You should have received a copy of the GNU General Public License
-# along with this program; if not, write to the Free Software
-# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
-# 02111-1307, USA.
+# Copyright (C) 2000-2001, 2004-2006, 2009-2010 Free Software Foundation, Inc.
+# This file is free software; the Free Software Foundation
+# gives unlimited permission to copy and/or distribute it,
+# with or without modifications, as long as this notice is preserved.
 
 # From Jim Meyering.
 
@@ -26,10 +14,10 @@ AC_DEFUN([gl_AC_DOS],
   [
     AC_CACHE_CHECK([whether system is Windows or MSDOS], [ac_cv_win_or_dos],
       [
-        AC_TRY_COMPILE([],
-        [#if !defined _WIN32 && !defined __WIN32__ && !defined __MSDOS__ && !defined __CYGWIN__
+        AC_COMPILE_IFELSE([AC_LANG_PROGRAM([], [[
+#if !defined _WIN32 && !defined __WIN32__ && !defined __MSDOS__ && !defined __CYGWIN__
 neither MSDOS nor Windows
-#endif],
+#endif]])],
         [ac_cv_win_or_dos=yes],
         [ac_cv_win_or_dos=no])
       ])
@@ -37,34 +25,47 @@ neither MSDOS nor Windows
     if test x"$ac_cv_win_or_dos" = xyes; then
       ac_fs_accepts_drive_letter_prefix=1
       ac_fs_backslash_is_file_name_separator=1
+      AC_CACHE_CHECK([whether drive letter can start relative path],
+                     [ac_cv_drive_letter_can_be_relative],
+        [
+          AC_COMPILE_IFELSE([AC_LANG_PROGRAM([], [[
+#if defined __CYGWIN__
+drive letters are always absolute
+#endif]])],
+          [ac_cv_drive_letter_can_be_relative=yes],
+          [ac_cv_drive_letter_can_be_relative=no])
+        ])
+      if test x"$ac_cv_drive_letter_can_be_relative" = xyes; then
+        ac_fs_drive_letter_can_be_relative=1
+      else
+        ac_fs_drive_letter_can_be_relative=0
+      fi
     else
       ac_fs_accepts_drive_letter_prefix=0
       ac_fs_backslash_is_file_name_separator=0
+      ac_fs_drive_letter_can_be_relative=0
     fi
 
-    AH_VERBATIM(FILESYSTEM_PREFIX_LEN,
-    [#if FILESYSTEM_ACCEPTS_DRIVE_LETTER_PREFIX
-# define FILESYSTEM_PREFIX_LEN(Filename) \
-  ((Filename)[0] && (Filename)[1] == ':' ? 2 : 0)
-#else
-# define FILESYSTEM_PREFIX_LEN(Filename) 0
-#endif])
-
-    AC_DEFINE_UNQUOTED([FILESYSTEM_ACCEPTS_DRIVE_LETTER_PREFIX],
+    AC_DEFINE_UNQUOTED([FILE_SYSTEM_ACCEPTS_DRIVE_LETTER_PREFIX],
       $ac_fs_accepts_drive_letter_prefix,
       [Define on systems for which file names may have a so-called
        `drive letter' prefix, define this to compute the length of that
        prefix, including the colon.])
 
     AH_VERBATIM(ISSLASH,
-    [#if FILESYSTEM_BACKSLASH_IS_FILE_NAME_SEPARATOR
+    [#if FILE_SYSTEM_BACKSLASH_IS_FILE_NAME_SEPARATOR
 # define ISSLASH(C) ((C) == '/' || (C) == '\\')
 #else
 # define ISSLASH(C) ((C) == '/')
 #endif])
 
-    AC_DEFINE_UNQUOTED([FILESYSTEM_BACKSLASH_IS_FILE_NAME_SEPARATOR],
+    AC_DEFINE_UNQUOTED([FILE_SYSTEM_BACKSLASH_IS_FILE_NAME_SEPARATOR],
       $ac_fs_backslash_is_file_name_separator,
       [Define if the backslash character may also serve as a file name
        component separator.])
+
+    AC_DEFINE_UNQUOTED([FILE_SYSTEM_DRIVE_PREFIX_CAN_BE_RELATIVE],
+      $ac_fs_drive_letter_can_be_relative,
+      [Define if a drive letter prefix denotes a relative path if it is
+       not followed by a file name component separator.])
   ])