Stack Funktionen hinzugefügt

highscores.txt

@@ -1 +1,2 @@
+player_name;9943
 player1;3999

stack.c

@@ -10,24 +10,64 @@
 // Pushes data as pointer onto the stack.
 StackNode *push(StackNode *stack, void *data)
 {
+    StackNode *newNode = malloc(sizeof(StackNode));
+    if(*newNode == NULL)
+    {
+        //printf("Fehler Bei Speicherallozierung!");
+        return NULL;
+    }
 
+    newNode->data = data;
+    newNode->next = stack;
+
+    return newNode;
 }
 
 // Deletes the top element of the stack (latest added element) and releases its memory. (Pointer to data has to be
 // freed by caller.)
 StackNode *pop(StackNode *stack)
 {
+    if(stack == NULL)
+    {
+        //printf("Fehlerhafte Adresse uebergeben");
+        return NULL;
+    }
 
+    StackNode *next = stack->next;
+
+    free(stack);
+
+    return next;
 }
 
 // Returns the data of the top element.
 void *top(StackNode *stack)
 {
+    if(stack == NULL)
+    {
+        //printf("Fehlerhafte Adresse uebergeben");
+        return NULL;
+    }
 
+    return stack->data;
 }
 
 // Clears stack and releases all memory.
 void clearStack(StackNode *stack)
 {
+    if(stack == NULL)
+    {
+        //printf("Fehlerhafte Adresse uebergeben");
+        return NULL;
+    }
 
+    StackNode *currentNode = stack;
+    StackNode *nextNode;
+
+    while(currentNode != NULL)
+    {
+        nextNode = currentNode->next;
+        free(currentNode);
+        currentNode = nextNode;
+    }
 }

stack.h

@@ -8,6 +8,11 @@ The latest element is taken from the stack. */
 #include <stdlib.h>
 
 //TODO: passenden Datentyp als struct anlegen
+typedef struct StackNode
+{
+    void *data;
+    struct SatckNode *next;
+} StackNode;
 
 // Pushes data as pointer onto the stack.
 StackNode *push(StackNode *stack, void *data);