1 files changed, 134 insertions, 0 deletions
diff --git a/interpreter/graphs.c b/interpreter/graphs.c
new file mode 100644
index 0000000..34877a2
--- /dev/null
+++ b/interpreter/graphs.c
@@ -0,0 +1,134 @@
+#include "graphs.h"
+
+#include <string.h>
+
+#include "mem.h"
+
+void use_node(struct node* node, unsigned int count) {
+	if (!node)
+		return;
+
+	node->used_count += count;
+
+	if (node->kind == EXPR_LIST ||
+			node->kind == EXPR_TUPLE ||
+			node->kind == EXPR_APP) {
+		use_node(node->var1, count);
+		use_node(node->var2, count);
+	}
+}
+
+void free_node(struct node* node, unsigned free_first) {
+	if (!node)
+		return;
+
+	node->used_count--;
+
+	if (node->kind == EXPR_LIST ||
+			node->kind == EXPR_TUPLE ||
+			node->kind == EXPR_APP) {
+		free_node((struct node*) node->var1, 1);
+		free_node((struct node*) node->var2, 1);
+	}
+
+	if (node->used_count == 0) {
+		if (node->kind == EXPR_INT || node->kind == EXPR_NAME)
+			my_free(node->var1);
+
+		if (node->kind == EXPR_CODE)
+			my_free(node->var2);
+
+		if (free_first)
+			my_free(node);
+	}
+}
+
+nodes_array* push_node(nodes_array* nodes, struct node* node) {
+	unsigned int i;
+	for (i = 0; i < nodes->length && nodes->nodes[i]; i++);
+	if (nodes->nodes[i])
+		nodes = my_realloc(nodes, sizeof(nodes_array) +
+				2 * nodes->length * sizeof(*node));
+	nodes->nodes[i] = node;
+	nodes->nodes[i + 1] = NULL;
+	return nodes;
+}
+
+void cpy_expression_to_node(struct node* dst, expression* src) {
+	if (!dst || !src)
+		return;
+
+	dst->kind = src->kind;
+	switch (src->kind) {
+		case EXPR_INT:
+			dst->var1 = my_calloc(1, sizeof(int));
+			*((int*) dst->var1) = *((int*) src->var1);
+			break;
+
+		case EXPR_NAME:
+			dst->var1 = my_calloc(1, 1 + strlen((char*) src->var1));
+			strcpy(dst->var1, src->var1);
+			break;
+
+		case EXPR_CODE:
+			dst->var1 = src->var1;
+			dst->var2 = my_calloc(1, sizeof(unsigned char));
+			*((unsigned char*) dst->var2) = *((unsigned char*) src->var2);
+			break;
+
+		case EXPR_LIST:
+		case EXPR_TUPLE:
+		case EXPR_APP:
+			dst->var1 = dst->var2 = NULL;
+			if (src->var1) {
+				dst->var1 = my_calloc(1, sizeof(struct node));
+				cpy_expression_to_node(dst->var1, src->var1);
+			}
+			if (src->var2) {
+				dst->var2 = my_calloc(1, sizeof(struct node));
+				cpy_expression_to_node(dst->var2, src->var2);
+			}
+	}
+
+	dst->used_count = 1;
+}
+
+void cpy_node_to_expression(expression* dst, struct node* src) {
+	if (!dst || !src)
+		return;
+
+	free_expression(dst);
+	dst->is_strict = 0;
+
+	dst->kind = src->kind;
+	switch (src->kind) {
+		case EXPR_INT:
+			dst->var1 = my_calloc(1, sizeof(int));
+			*((int*) dst->var1) = *((int*) src->var1);
+			break;
+
+		case EXPR_NAME:
+			dst->var1 = my_calloc(1, 1 + strlen((char*) src->var1));
+			strcpy(dst->var1, src->var1);
+			break;
+
+		case EXPR_CODE:
+			dst->var1 = src->var1;
+			dst->var2 = my_calloc(1, sizeof(unsigned char));
+			*((unsigned char*) dst->var2) = *((unsigned char*) src->var2);
+			break;
+
+		case EXPR_LIST:
+		case EXPR_TUPLE:
+		case EXPR_APP:
+			dst->var1 = dst->var2 = NULL;
+			if (src->var1) {
+				dst->var1 = my_calloc(1, sizeof(expression));
+				cpy_node_to_expression(dst->var1, src->var1);
+			}
+			if (src->var2) {
+				dst->var2 = my_calloc(1, sizeof(expression));
+				cpy_node_to_expression(dst->var2, src->var2);
+			}
+	}
+}