--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/old-trunk/lwasm/old/lwval.c	Fri Mar 19 02:54:14 2010 +0000
@@ -0,0 +1,211 @@
+/*
+lwval.c
+Copyright © 2008 William Astle
+
+This file is part of LWASM.
+
+LWASM 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/>.
+*/
+
+/*
+This file contains implementations associated with the expression evaluator
+used by LWASM.
+
+*/
+#include <config.h>
+
+#include <malloc.h>
+
+#define __lwval_c_seen__
+#include "lwval.h"
+
+LWVAL *lwval_construct_int(int value)
+{
+	LWVAL *v;
+	
+	v = malloc(sizeof(LWVAL));
+	if (!v)
+		return NULL;
+	
+	v -> lwval_type = LWVAL_TYPE_INT;
+	v -> dt.lwval_int = value;
+	
+	return v;
+}
+
+LWVAL *lwval_construct_err(int errno)
+{
+	LWVAL *v;
+	
+	v = malloc(sizeof(LWVAL));
+	if (!v)
+		return NULL;
+	
+	v -> lwval_type = LWVAL_TYPE_ERR;
+	v -> dt.lwval_int = errno;
+	
+	return v;
+}
+
+LWVAL *lwval_construct_nan(void)
+{
+	LWVAL *v;
+	
+	v = malloc(sizeof(LWVAL));
+	if (!v)
+		return NULL;
+	
+	v -> lwval_type = LWVAL_TYPE_NAN;
+	
+	return v;
+}
+
+LWVAL *lwval_construct_undef(void)
+{
+	LWVAL *v;
+	
+	v = malloc(sizeof(LWVAL));
+	if (!v)
+		return NULL;
+	
+	v -> lwval_type = LWVAL_TYPE_UNDEF;
+	
+	return v;
+}
+
+LWVAL *lwval_construct_expr(LWVAL *v1, LWVAL *v2, int op)
+{
+	LWVAL *v;
+	v = malloc(sizeof(LWVAL));
+	if (!v)
+		return NULL;
+	
+	v -> lwval_type = LWVAL_TYPE_EXPR;
+	v -> dt.expr.v1 = v1;
+	v -> dt.expr.v2 = v2;
+	v -> dt.expr.op = op;
+	return v;
+}
+
+void lwval_destroy(LWVAL *value)
+{
+	if (value)
+	{
+		lwval_clear(value);
+		free(value);
+	}
+}
+
+// performs a deep copy of an LWVAL, including ALL referenced values
+void lwval_dup(LWVAL *v1, LWVAL *v2)
+{
+	lwval_clear(v2);
+	
+	switch (v1 -> lwval_type)
+	{
+	case LWVAL_TYPE_INT:
+	case LWVAL_TYPE_ERR:
+		v2 -> dt.lwval_int = v1 -> dt.lwval_int;
+		break;
+	
+	case LWVAL_TYPE_EXPR:
+		v2 -> dt.expr.op = v1 -> dt.expr.op;
+		if (v1 -> dt.expr.v1)
+		{
+			v2 -> dt.expr.v1 = lwval_construct_undef();
+			lwval_dup(v1 -> dt.expr.v1, v2 -> dt.expr.v1);
+		}
+		else
+			v2 -> dt.expr.v1 = NULL;
+		if (v1 -> dt.expr.v2)
+		{
+			v2 -> dt.expr.v2 = lwval_construct_undef();
+			lwval_dup(v1 -> dt.expr.v2, v2 -> dt.expr.v2);
+		}
+		else
+			v2 -> dt.expr.v2 = NULL;
+		break;
+	}
+	
+	v2 -> lwval_type = v1 -> lwval_type;
+}
+
+void lwval_clear(LWVAL *value)
+{
+	switch (value -> lwval_type)
+	{
+	case LWVAL_TYPE_EXPR:
+		lwval_destroy(value -> dt.expr.v1);
+		lwval_destroy(value -> dt.expr.v2);
+		break;
+	}
+	value -> lwval_type = LWVAL_TYPE_UNDEF;
+}
+
+// for integer, simply negate value
+// for expr, change to "-1 * (expr)"
+// everything else: error
+LWVAL *lwval_neg(LWVAL *v1)
+{
+	switch (v1 -> lwval_type)
+	{
+	case LWVAL_TYPE_INT:
+		v1 -> dt.lwval_int = -(v1 -> dt.lwval_int);
+		break;
+	
+	case LWVAL_TYPE_EXPR:
+		{
+			LWVAL *v, *v2;
+			v = lwval_construct_undef();
+			lwval_dup(v1, v);
+			lwval_clear(v1);
+			v2 = lwval_construct_expr(lwval_construct_int(-1), v, '*');
+			lwval_dup(v2, v1);
+			lwval_destroy(v2);
+		}
+		break;
+	
+	default:
+		lwval_clear(v1);
+		v1 -> lwval_type = LWVAL_TYPE_ERR;
+		v1 -> dt.lwval_int = 1;
+	}
+	
+	return v1;
+}
+
+// v1 + v2 -> v1
+LWVAL *lwval_add(LWVAL *v1, LWVAL *v2)
+{
+}
+
+// v1 - v2 -> v1
+LWVAL *lwval_sub(LWVAL *v1, LWVAL *v2)
+{
+}
+
+// v1 * v2 -> v1
+LWVAL *lwval_mul(LWVAL *v1, LWVAL *v2)
+{
+}
+
+// v1 / v2 -> v1
+LWVAL *lwval_div(LWVAL *v1, LWVAL *v2)
+{
+}
+
+// v1 % v2 -> v1
+LWVAL *lwval_mod(LWVAL *v1, LWVAL *v2)
+{
+}