arbeiten an stack.c

stack.c

@@ -69,11 +69,15 @@ StackNode *pop(StackNode *stack) {
 void *top(StackNode *stack) { return stack != NULL ? stack->data : NULL; }
 
 // Clears stack and releases all memory.
-StackNode *clearStack(StackNode *stack) {
+void clearStack(StackNode *stack) {
 
   while (stack != NULL) {
 
     StackNode *next = stack->next;
+    stack->data = NULL;
+    stack->prev = NULL;
+    stack->next = NULL;
+    
     free(stack);
     stack = next;
   }

stack.h

@@ -13,6 +13,7 @@ typedef struct StackNode {
 
   void *data;
   struct StackNode *next;
+  struct StackNode *prev;
 
 } StackNode;
 
@@ -29,6 +30,6 @@ StackNode *pop(StackNode *stack);
 void *top(StackNode *stack);
 
 // Clears stack and releases all memory.
-StackNode *clearStack(StackNode *stack);
+void clearStack(StackNode *stack);
 
 #endif

test_stack.c

@@ -36,7 +36,7 @@ void test_clearStack(void) {
     testStack = push(testStack, &testInts[i]);
   }
 
-  testStack = clearStack(testStack);
+  clearStack(testStack);
   TEST_ASSERT_NULL(testStack);
 }