From eecfe653e39c6bc336e693c3f8362f209ce9bfa3 Mon Sep 17 00:00:00 2001
From: Danila Fedorin <danila.fedorin@gmail.com>
Date: Thu, 8 Feb 2018 18:40:56 -0800
Subject: [PATCH] Fix incorrect deletion code.

---
 src/eval.c | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/src/eval.c b/src/eval.c
index 0a062be..c3805f9 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -50,16 +50,18 @@ liblex_result _eval_config_free_state(eval_state* state) {
 
 liblex_result eval_config_remove(eval_config* config, const char* pattern, int pattern_id) {
   liblex_result result = LIBLEX_SUCCESS;
-  ll_node** head = &(config->states.head);
-  while(*head && result == LIBLEX_SUCCESS) {
-    eval_state* current_state = (*head)->data;
+  ll_node* head = config->states.head;
+  while(head && result == LIBLEX_SUCCESS) {
+    eval_state* current_state = head->data;
     if(strcmp(current_state->source, pattern) == 0 && current_state->pattern->head->pattern_id == pattern_id) {
-      ll_node* to_delete = *head;
-      (*head) = (*head)->next;
+      ll_node* to_delete = head;
+      head = head->next;
+      *(to_delete->prev ? &to_delete->prev->next : &(config->states.head)) = to_delete->next;
+      *(to_delete->next ? &to_delete->next->prev : &(config->states.tail)) = to_delete->prev;
       free(to_delete);
       result = _eval_config_free_state(current_state);
     } else {
-      head = &((*head)->next);
+      head = head->next;
     }
   }
   return result;