Remove elements from a binary search tree based on a condition

Question

I have a Struct that stores the name of a file and the day it was last accessed.

typedef struct sFile {
   int lastAccess;
   char name[50];
} File;

typedef struct sNode {
   File info;
   struct sNode* left;
   struct sNode* right;
} Node;

I coded a function that recursively removes files that have their access day less than a certain number. For example, when you call this function and pass 10 as a parameter, all files that have access day less than 10 will be deleted.

However, I'm having problems with the execution of the same and ends up generating a memory access error.

I believe my insertion and removal functions are correct but just in case I'm leaving them below.

Insert and Delete Functions:

void insert(Node **root, File value) {
   if(*root == NULL) {
      Node *celula = getNode();
      
      if(celula == NULL) {
         printf("\nERRO: Falha na alocacao de memoria. Encerrando programa.\n");
         exit(1);
      }

      celula->left = NULL;
      celula->right = NULL;
      celula->info = value;
      *root = celula ;
   } else {
      if(strcmp(value.name, (*root)->info.name) < 0) {
         insert(&(*root)->left, value);
      } else {
         insert(&(*root)->right, value);
      }
   }
};

Node* deleteNode(Node *root, char name[50]) {
    if (root == NULL)
        return root;
 
    if (strcmp(name, root->info.name) < 0)
        root->left = deleteNode(root->left, name);
 
    else if (strcmp(name, root->info.name) > 0)
        root->right = deleteNode(root->right, name);
 
    else {
        if (root->left == NULL) {
            Node *temp = root->right;
            free(root);
            return temp;
        }
        else if (root->right == NULL) {
            Node *temp = root->left;
            free(root);
            return temp;
        }
 
        Node *temp = minValueNode(root->right);
 
        root->info = temp->info;
 
        root->right = deleteNode(root->right, temp->info.name);
    }
    return root;
}

Tree cleaning function:

Node* clear(Node *root, int date) {
   if(root == NULL) {
      return NULL;
   }

   if(root->info.lastAccess <= date) {
      root = deleteNode(root, (root)->info.name);
   }

   root = clear(root->left, date);
   root = clear(root->right, date);

   return root;
}

Error Message:

[1]    39970 segmentation fault (core dumped)  ./7.out

Does anyone have any idea what might be causing this error and how I can fix it?

Answer 1

I was able to find the error. Thanks to everyone who helped.

I was returning NULL to the root of the tree, so I lost all tree reference and consequently performed an improper memory access. I updated the clear function to the following:

Node* clear(Node *root, int date) {
   if(root == NULL) {
      return NULL;
   }

   if(root->info.lastAccess <= date) {
      root = deleteNode(root, (root)->info.name);
   }

   root->left = clear(root->left, date);
   root->right = clear(root->right, date);

   return root;
}