--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libiberty/filename_cmp.c	Fri Jul 17 14:47:48 2009 +0900
@@ -0,0 +1,78 @@
+/* File name comparison routine.
+
+   Copyright (C) 2007 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., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA.  */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#ifdef HAVE_STRING_H
+#include <string.h>
+#endif
+
+#include "filenames.h"
+#include "safe-ctype.h"
+
+/*
+
+@deftypefn Extension int filename_cmp (const char *@var{s1}, const char *@var{s2})
+
+Return zero if the two file names @var{s1} and @var{s2} are equivalent.
+If not equivalent, the returned value is similar to what @code{strcmp}
+would return.  In other words, it returns a negative value if @var{s1}
+is less than @var{s2}, or a positive value if @var{s2} is greater than
+@var{s2}.
+
+This function does not normalize file names.  As a result, this function
+will treat filenames that are spelled differently as different even in
+the case when the two filenames point to the same underlying file.
+However, it does handle the fact that on DOS-like file systems, forward
+and backward slashes are equal.
+
+@end deftypefn
+
+*/
+
+int
+filename_cmp (const char *s1, const char *s2)
+{
+#ifndef HAVE_DOS_BASED_FILE_SYSTEM
+  return strcmp(s1, s2);
+#else
+  for (;;)
+    {
+      int c1 = TOLOWER (*s1);
+      int c2 = TOLOWER (*s2);
+
+      /* On DOS-based file systems, the '/' and the '\' are equivalent.  */
+      if (c1 == '/')
+        c1 = '\\';
+      if (c2 == '/')
+        c2 = '\\';
+
+      if (c1 != c2)
+        return (c1 - c2);
+
+      if (c1 == '\0')
+        return 0;
+
+      s1++;
+      s2++;
+    }
+#endif
+}
+