--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwasm/input.c	Sat Feb 13 06:08:26 2010 +0000
@@ -0,0 +1,83 @@
+/*
+input.c
+
+Copyright © 2010 William Astle
+
+This file is part of LWTOOLS.
+
+LWTOOLS 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 3 of the License, 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, see <http://www.gnu.org/licenses/>.
+*/
+
+#include <config.h>
+
+/*
+This file is used to handle reading input files. It serves to encapsulate
+the entire input system to make porting to different media and systems
+less difficult.
+*/
+
+#include <lw_alloc.h>
+#include <lw_stringlist.h>
+
+struct input_layer
+{
+	lw_stringlist_t inputlist;
+	struct input_layer *nextlayer;
+	
+	FILE *fp;
+};
+
+
+static struct input_layer *layerstack = NULL;
+
+void input_push(lw_stringlist_t list)
+{
+	struct input_layer *i;
+	
+	i = lw_alloc(sizeof(struct input_layer));
+	i -> nextlayer = layerstack;
+	layerstack = i;
+	i -> inputlist = lw_stringlist_copy(list);
+}
+
+/* fetch a line of input from the top of the input stack */
+/* return NULL if no input left */
+char *input_fetchline(void)
+{
+again:
+	if (!layerstack)
+		return NULL;
+	
+	if (!layerstack -> fp)
+	{
+		// no open file
+		char *fn;
+		
+		fn = lw_stringlist_current(layerstack -> inputlist);
+		lw_stringlist_next(layerstack -> inputlist);
+		if (!fn)
+		{
+			struct input_list *t;
+			t = layerstack;
+			layerstack = layerstack -> nextlayer;
+			lw_stringlist_destroy(t -> inputlist);
+			lw_free(t);
+			goto again;
+		}
+		
+		// open the file here
+	}
+	
+	
+}