[patch/libiberty] IS_ABSOLUTE_PATH to handle both DOS and POSIX p ath styles

[Aleksandar Ristovski <ARistovski@qnx.com>]

Resending this patch with libiberty in the subject line, as per:
http://sourceware.org/ml/gdb-patches/2008-01/msg00063.html


This patch introduces new IS_DIR_SEPARATOR_? And IS_ABSOLUTE_PATH_? Macros.

Old macros IS_DIR_SEPARATOR and IS_ABSOLUTE_PATH continue to be configured
host dependent.

Please see http://sourceware.org/ml/gdb/2008-01/msg00021.html for details on
why this patch.

---
Aleksandar Ristovski
QNX Software Systems

ChangeLog:
2008-01-04  Aleksandar Ristovski  <aristovski@qnx.com>

        * filenames.h (IS_DIR_SEPARATOR_DOS): New macro.
        (IS_ABSOLUTE_PATH_DOS): New macro.
        (IS_DIR_SEPARATOR_X): New macro.
        (IS_ABSOLUTE_PATH_X): New macro.
        (IS_DIR_SEPARATOR_ANY): New macro.
        (IS_ABSOLUTE_PATH_ANY): New macro.


Index: include/filenames.h
===================================================================
RCS file: /cvs/src/src/include/filenames.h,v
retrieving revision 1.4
diff -u -3 -p -r1.4 filenames.h
--- include/filenames.h	29 Mar 2007 21:03:43 -0000	1.4
+++ include/filenames.h	4 Jan 2008 19:22:02 -0000
@@ -26,6 +26,23 @@ Foundation, Inc., 51 Franklin Street - F
 #ifndef FILENAMES_H
 #define FILENAMES_H
 
+/* For DOS style paths. Note that these macros do not recognize
+  path starting with '/' as an absolute path.  */
+
+#define IS_DIR_SEPARATOR_DOS(c)	  ((c) == '/' || (c) == '\\')
+#define IS_ABSOLUTE_PATH_DOS(f)	  (((f)[0]) && ((f)[1] == ':'))
+
+/* For POSIX style paths.  */
+
+#define IS_DIR_SEPARATOR_X(c)	  ((c) == '/')
+#define IS_ABSOLUTE_PATH_X(f)	  (IS_DIR_SEPARATOR_X((f)[0]))
+
+/* Universal macros, to be used on paths that could be either
+   POSIX or DOS.  */
+
+#define IS_DIR_SEPARATOR_ANY(c)	  (IS_DIR_SEPARATOR_DOS(c))
+#define IS_ABSOLUTE_PATH_ANY(f)	  (IS_ABSOLUTE_PATH_X(f) ||
IS_ABSOLUTE_PATH_DOS(f))
+
 #if defined(__MSDOS__) || defined(_WIN32) || defined(__OS2__) || defined
(__CYGWIN__)
 
 #ifndef HAVE_DOS_BASED_FILE_SYSTEM