--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwcc/tree.c	Sat Sep 21 18:43:39 2013 -0600
@@ -0,0 +1,139 @@
+/*
+lwcc/tree.c
+
+Copyright © 2013 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 <stdarg.h>
+#include <string.h>
+#include <lw_alloc.h>
+
+#include "tree.h"
+
+static char *node_names[] = {
+	"NONE",
+	"PROGRAM",
+};
+
+
+
+node_t *node_create(int type, ...)
+{
+	node_t *r;
+	int nargs = 0;
+	va_list args;
+	
+	va_start(args, type);
+	r = lw_alloc(sizeof(node_t));
+	memset(r, sizeof(node_t), 0);
+	r -> type = type;
+	
+	switch (type)
+	{
+	}
+	
+	while (nargs--)
+	{
+		node_addchild(r, va_arg(args, node_t *));
+	}
+	va_end(args);
+	return r;
+}
+
+void node_destroy(node_t *node)
+{
+	node_t *n;
+	
+	while (node -> children)
+	{
+		n = node -> children -> next_child;
+		node_destroy(node -> children);
+		node -> children = n;
+	}
+	lw_free(node -> strval);
+	lw_free(node);
+}
+
+void node_addchild(node_t *node, node_t *nn)
+{
+	node_t *tmp;
+	
+	nn -> parent = node;
+	nn -> next_child = NULL;
+	if (node -> children)
+	{
+		for (tmp = node -> children; tmp -> next_child; tmp = tmp -> next_child)
+			/* do nothing */ ;
+		tmp -> next_child = nn;
+	}
+	else
+	{
+		node -> children = nn;
+	}
+}
+
+void node_removechild(node_t *node, node_t *nn)
+{
+	node_t **pp;
+	node_t *np;
+	
+	if (!node)
+		node = nn -> parent;
+	
+	pp = &(node -> children);
+	for (np = node -> children; np; np = np -> next_child)
+	{
+		if (np -> next_child == nn)
+			break;
+		pp = &((*pp) -> next_child);
+	}
+	if (!np)
+		return;
+	
+	*pp = nn -> next_child;
+	nn -> parent = NULL;
+	nn -> next_child = NULL;
+}
+
+void node_removechild_destroy(node_t *node, node_t *nn)
+{
+	node_removechild(node, nn);
+	node_destroy(nn);
+}
+
+static void node_display_aux(node_t *node, FILE *f, int level)
+{
+	node_t *nn;
+	int i;
+	
+	for (i = 0; i < level * 4; i++)
+		fputc(' ', f);
+	fprintf(f, "(%s ", node_names[node -> type]);
+	fputc('\n', f);
+	for (nn = node -> children; nn; nn = nn -> next_child)
+		node_display_aux(nn, f, level + 1);
+	for (i = 0; i < level * 4; i++)
+		fputc(' ', f);
+	fputc(')', f);
+	fputc('\n', f);
+}
+
+void node_display(node_t *node, FILE *f)
+{
+	node_display_aux(node, f, 0);
+}