From 2de4f7b46000fea3cb0327144233029e22b3d4a1 Mon Sep 17 00:00:00 2001
From: servostar <sven.vogel123@web.de>
Date: Wed, 5 Jun 2024 14:37:34 +0200
Subject: [PATCH] fixed: ast memory leak leaf nodes

---
 src/ast/ast.c | 47 +++++++++++++++++++++++++++++------------------
 src/ast/ast.h | 17 +++++++++++++++--
 2 files changed, 44 insertions(+), 20 deletions(-)

diff --git a/src/ast/ast.c b/src/ast/ast.c
index 4c8caa4..d36b530 100644
--- a/src/ast/ast.c
+++ b/src/ast/ast.c
@@ -41,6 +41,20 @@ AST_NODE_PTR AST_new_node(TokenLocation location, enum AST_SyntaxElement_t kind,
     return node;
 }
 
+size_t AST_child_count(AST_NODE_PTR node) {
+    assert(node != NULL);
+    assert(node->children != NULL);
+
+    return node->children->len;
+}
+
+AST_NODE_PTR AST_get_last_node(AST_NODE_PTR node) {
+    assert(node != NULL);
+    assert(node->children != NULL);
+
+    return AST_get_node(node, AST_child_count(node) - 1);
+}
+
 static const char *lookup_table[AST_ELEMENT_COUNT] = {"__UNINIT__"};
 
 void AST_init() {
@@ -175,7 +189,7 @@ AST_NODE_PTR AST_get_node(AST_NODE_PTR owner, const size_t idx) {
         PANIC("AST owner node has no children");
     }
 
-    AST_NODE_PTR child = ((AST_NODE_PTR*) owner->children->data)[idx];
+    AST_NODE_PTR child = ((AST_NODE_PTR *) owner->children->data)[idx];
 
     if (child == NULL) {
         PANIC("child node is NULL");
@@ -198,14 +212,12 @@ AST_NODE_PTR AST_remove_child(AST_NODE_PTR owner, const size_t idx) {
     return child;
 }
 
-AST_NODE_PTR AST_detach_child(AST_NODE_PTR owner, AST_NODE_PTR child) {
-    assert(owner != NULL);
+AST_NODE_PTR AST_detach_child(AST_NODE_PTR child) {
     assert(child != NULL);
-    assert(owner->children != NULL);
 
-    for (size_t i = 0; i < owner->children->len; i++) {
-        if (AST_get_node(owner, i) == child) {
-            return AST_remove_child(owner, i);
+    for (size_t i = 0; i < AST_child_count(child->parent); i++) {
+        if (AST_get_node(child->parent, i) == child) {
+            return AST_remove_child(child->parent, i);
         }
     }
 
@@ -217,23 +229,22 @@ void AST_delete_node(AST_NODE_PTR node) {
 
     DEBUG("Deleting AST node: %p", node);
 
-    if (node->children == NULL) {
-        return;
-    }
-
     if (node->parent != NULL) {
-        AST_NODE_PTR child = AST_detach_child(node->parent, node);
+        AST_NODE_PTR child = AST_detach_child(node);
         assert(child == node);
     }
 
-    for (size_t i = 0; i < node->children->len; i++) {
-        // prevent detach of children node
-        AST_NODE_PTR child = AST_get_node(node, i);
-        child->parent = NULL;
-        AST_delete_node(child);
+    if (node->children != NULL) {
+        for (size_t i = 0; i < AST_child_count(node); i++) {
+            AST_NODE_PTR child = AST_get_node(node, i);
+            // prevent detach of children node
+            child->parent = NULL;
+            AST_delete_node(child);
+        }
+
+        g_array_free(node->children, TRUE);
     }
 
-    g_array_free(node->children, TRUE);
     free(node);
 }
 
diff --git a/src/ast/ast.h b/src/ast/ast.h
index a619bb1..4fc8c88 100644
--- a/src/ast/ast.h
+++ b/src/ast/ast.h
@@ -112,6 +112,20 @@ void AST_init(void);
 [[gnu::nonnull(1)]]
 const char* AST_node_to_string(AST_NODE_PTR node);
 
+/**
+ * @brief Return the amount of children
+ * @param node
+ * @return
+ */
+size_t AST_child_count(AST_NODE_PTR node);
+
+/**
+ * @brief Return the last node of the children
+ * @param node
+ * @return
+ */
+AST_NODE_PTR AST_get_last_node(AST_NODE_PTR node);
+
 /**
  * @brief Create a new node struct on the system heap. Initializes the struct with the given values.
  *        All other fields are set to either NULL or 0. No allocation for children array is preformed.
@@ -162,13 +176,12 @@ AST_NODE_PTR AST_remove_child(AST_NODE_PTR owner, size_t idx);
  * @brief Detach a child from its parent. This involves removing the child from its parent
  *        and marking the parent of the child as NULL.
  * @attention The returned pointer is still valid. It must be freed at some pointer later.
- * @param owner the owner to remove the child from
  * @param child the child to detach
  * @return a pointer to child detached
  */
 [[nodiscard("pointer must be freed")]]
 [[gnu::nonnull(1), gnu::nonnull(1)]]
-AST_NODE_PTR AST_detach_child(AST_NODE_PTR owner, AST_NODE_PTR child);
+AST_NODE_PTR AST_detach_child(AST_NODE_PTR child);
 
 /**
  * @brief Return a pointer to the n-th child of a node