From: Lukas Jiriste <ljiriste@student.42prague.com>
Date: Fri, 21 Jun 2024 07:43:38 +0000 (+0200)
Subject: Fix the code to actually produce a tree
X-Git-Url: https://git.ljiriste.work/?a=commitdiff_plain;h=faa06ffa7159c575c44abbf5caeddae16e3bc9a0;p=Libft.git

Fix the code to actually produce a tree

As the previous commit was only checked to compile there were some
minor defects. Notably the parser stack was not initialized properly.
It has to return state_num 0 when empty, which was solved by inserting
a dummy state 0 wih no node attached.
---

diff --git a/ft_parse/ft_parse.c b/ft_parse/ft_parse.c
index bef5a61..e101c5c 100644
--- a/ft_parse/ft_parse.c
+++ b/ft_parse/ft_parse.c
@@ -6,7 +6,7 @@
 /*   By: ljiriste <ljiriste@student.42prague.com>   +#+  +:+       +#+        */
 /*                                                +#+#+#+#+#+   +#+           */
 /*   Created: 2024/05/20 20:51:36 by ljiriste          #+#    #+#             */
-/*   Updated: 2024/06/20 17:45:45 by ljiriste         ###   ########.fr       */
+/*   Updated: 2024/06/21 09:39:33 by ljiriste         ###   ########.fr       */
 /*                                                                            */
 /* ************************************************************************** */
 
@@ -20,6 +20,8 @@ void	ft_parse_tree_free(void *v_node)
 	t_parse_tree_node	*node;
 
 	node = v_node;
+	if (!node)
+		return ;
 	ft_vec_free(&node->children, ft_parse_tree_free);
 	free_token(&node->token);
 	return ;
@@ -30,6 +32,8 @@ void	ft_stack_element_free(void *v_el)
 	t_parser_stack_element	*el;
 
 	el = v_el;
+	if (!el)
+		return ;
 	ft_parse_tree_free(el->node);
 	return ;
 }
@@ -114,7 +118,18 @@ int	follow_rule(t_stack *stack, size_t rule_num, t_parsing_table *table)
 	return (ft_stack_push(stack, &element) != success || element.state_num < 0);
 }
 
-t_parse_tree_node	*ft_parse(__attribute__((unused)) t_vec *tokens, __attribute__((unused)) t_parsing_table *table)
+void	initialize_parser_stack(t_stack *stack)
+{
+	t_parser_stack_element	zero;
+
+	zero.state_num = 0;
+	zero.node = NULL;
+	ft_stack_init(stack, sizeof(t_parser_stack_element));
+	ft_stack_push(stack, &zero);
+	return ;
+}
+
+t_parse_tree_node	*ft_parse(t_vec *tokens, t_parsing_table *table)
 {
 	t_stack				stack;
 	size_t				i;
@@ -124,13 +139,13 @@ t_parse_tree_node	*ft_parse(__attribute__((unused)) t_vec *tokens, __attribute__
 	ssize_t				column;
 	t_parse_tree_node	*root;
 
-	ft_stack_init(&stack, sizeof(t_parser_stack_element));
+	initialize_parser_stack(&stack);
 	i = 0;
 	while (1)
 	{
 		if (i < tokens->size)
 			token = *(t_token *)ft_vec_access(tokens, i);
-		if (i == tokens->size)
+		else if (i == tokens->size)
 			token = (t_token){.type = "$", .str = NULL};
 		else
 		{
@@ -140,7 +155,7 @@ t_parse_tree_node	*ft_parse(__attribute__((unused)) t_vec *tokens, __attribute__
 		state = ft_vec_access(&table->states,
 			((t_parser_stack_element *)ft_stack_top(&stack))->state_num);
 		column = find_token_index(token, &table->tokens);
-		if (column < 0 || (size_t)column + 1 > table->terminal_tokens_num)
+		if (column < 0 || (size_t)column > table->terminal_tokens_num)
 		{
 			ft_stack_free(&stack, ft_stack_element_free);
 			return (NULL);