Add concept of "current working URI".

src/core/cwuri.c

@@ -0,0 +1,42 @@
+/*
+ * Copyright (C) 2007 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * 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 of the
+ * License, or 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <stddef.h>
+#include <gpxe/uri.h>
+
+/** @file
+ *
+ * Current working URI
+ *
+ * Somewhat analogous to the current working directory in a POSIX
+ * system.
+ */
+
+/** Current working URI */
+struct uri *cwuri = NULL;
+
+/**
+ * Change working URI
+ *
+ * @v uri		New working URI
+ */
+void churi ( struct uri *uri ) {
+	if ( cwuri )
+		uri_put ( cwuri );
+	cwuri = uri_get ( uri );
+}