Thread: Some functionality in generic Red-Black tree - C

Hey everyone.
So, my final project in C deals with generic Red Black tree data structure.
I have only one function to implement to finish this project but some bugs occur with him.
I think the problem is with the copy pointer, as it's passed as a pointer and not as a pointer to pointer, so if I am modifying it - it doesn't effect the "real one".

We mustn't change the signature of the functions and this is my problem.

Code:

/**
 * Represents a vector. The double* should be dynamically allocated
 */
typedef struct Vector
{
    int len;
    double *vector;
} Vector;


/**
 * copy pVector to pMaxVector if : 1. The norm of pVector is greater then the norm of pMaxVector.
 *                                    2. pMaxVector == NULL.
 * @param pVector pointer to Vector
 * @param pMaxVector pointer to Vector
 * @return 1 on success, 0 on failure (if pVector == NULL: failure).
 */
int copyIfNormIsLarger(const void *pVector, void *pMaxVector); // implement it in Structs.c

There is some functionality which depends on this function (when the current data in the tree is Vector) from above:

Code:

/*
 * a node of the tree.
 */
typedef struct Node
{
    struct Node *parent, *left, *right;
    Color color;
    void *data;


} Node;


/**
 * represents the tree
 */
typedef struct RBTree
{
    Node *root;
    CompareFunc compFunc;
    FreeFunc freeFunc;
    int size;
} RBTree;
/**
 * a function to apply on all tree items.
 * @object: a pointer to an item of the tree.
 * @args: pointer to other arguments for the function.
 * @return: 0 on failure, other on success.
 */
typedef int (*forEachFunc)(const void *object, void *args);

/**
 * Helper function to forEachRBTree which is in charge to recurse the BST in ascending order while activating each
 * one of the nodes.
 * @param tree: the tree with all the items.
 * @param func: the function to activate on all items.
 * @param args: more optional arguments to the function (may be null if the given function support it).
 * @param indicator: if the func is failed - indicator will be assigned with -1 indicating failure.
 * @return: 0 on failure, other on success.
 */
void forEachRBTreeHelper(Node *node, forEachFunc func, void *args, int* indicator)
{
    if (node == NULL)
    {
        return;
    }


    /* first recur on left child */
    forEachRBTreeHelper(node->left, func, args, indicator);


    /* then activate the func on node */
    if (node->data == NULL || func(node->data, args) == 0) {
        *indicator = -1; // failed!
    }


    /* now recur on right child */
    forEachRBTreeHelper(node->right, func, args, indicator);
}


int forEachRBTree(RBTree *tree, forEachFunc func, void *args) {
    if (tree == NULL || func == NULL) {
        return 0;
    }


    int indicator = 0;
    forEachRBTreeHelper(tree->root, func, args, &indicator); // Recurse and activate func
    if (indicator == -1) {
        return 0;
    }


    return 1;
}


/**
 * free all memory of the data structure using in-order recursion in order to not to cause memory leaks.
 * @param node: the current node to free.
 */
void freeRBTreeHelper(Node* node) {
    if (node == NULL) {
        return;
    }


    freeRBTreeHelper(node->left);


    if (node->right == NULL && node->left == NULL) {
        free(node);
    }


    freeRBTreeHelper(node->right);
}

So, I have a bug in one of the functions: copyIfNormIsLarger (I have a nonsense implementation so I don't even attach it), forEachRBTree or in forEachRBTreeHelper.

Can someone help me with that?

Thanks in advance!