Segmentation Fault Binary Tree Traversal - c

Question

So i've been running and testing my code and everything seemed to have been working until i added 2 more functions for Pre-order and Post-order traversals of my tree.
The assignment was to create a linked list and tree for an input file with a random set of numbers. The linked list and tree traversals all need to be printed out in separate functions and i can't find where i went wrong.
i keep getting
Segmentation Fault (core dumped)
Here is my code:
//Tristan Shepherd
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
struct node
{
int num;
struct node *next;
};
struct tree
{
int numt;
struct tree *left;
struct tree *right;
};
typedef struct node LINK;
typedef struct tree branch;
int searchList(int number, LINK *head)
{
LINK *current;
current = head;
while (current != NULL)
{
if (current->num == number)
return 1; // Found it.
current = current->next;
}
return 0; // Did not find it.
}
LINK *insertList(int number, LINK *head)
{
LINK *current, *temp;
if (searchList(number, head) == 1) return head;
temp = (LINK *)malloc(sizeof(LINK));
temp->num = number;
if (head == NULL)
{
head = temp;
temp->next = NULL;
return head;
}
current = head;
if (current->num == number)
{
temp->next = current;
head = temp;
return head;
}
current = head;
while (current != NULL)
{
if (current->next == NULL || current->next->num == number)
{
temp->next = current->next;
current->next = temp;
return head;
}
current = current->next;
}
}
void printList(LINK *head)
{
LINK *current;
current = head;
while (current != NULL)
{
printf("%i\n", current->num);
current = current->next;
}
}
LINK *freeList(LINK *head)
{
LINK *current, *temp;
current = head;
while (current != NULL)
{
temp = current;
current = current->next;
free(temp);
}
free(head);
head = NULL;
return head;
}
void freeTree(branch *leaf)
{
if(leaf != 0)
{
freeTree(leaf->left);
freeTree(leaf->right);
free(leaf);
}
}
void insert(int new, branch **leaf)
{
if(*leaf == 0)
{
*leaf = (struct tree*) malloc(sizeof(struct tree));
(*leaf)->numt = new;
(*leaf)->left = 0;
(*leaf)->right = 0;
}
else if(new < (*leaf)->numt)
{
insert(new, &(*leaf)->left);
}
else if(new > (*leaf)->numt)
{
insert(new, &(*leaf)->right);
}
}
void printInorder(branch *leaf)
{
if (leaf == NULL)
return;
printInorder(leaf->left);
printf("%i ", leaf->numt);
printInorder(leaf->right);
}
void printPreorder(branch *leaf)
{
if (leaf == NULL)
return;
printf("%i ", leaf->numt);
printInorder(leaf->left);
printInorder(leaf->right);
}
void printPostorder(branch *leaf)
{
if (leaf == NULL)
return;
printInorder(leaf->left);
printInorder(leaf->right);
printf("%i ", leaf->numt);
}
int main (void)
{
int t;
FILE *stream = fopen("hw9.data", "r");
LINK *head;
branch *leaf;
head = NULL;
int number;
while (1)
{
fscanf(stream, "%i", &number);
if (feof(stream)) break;
insert(number, &leaf);
head = insertList(number, head);
}
fclose(stream);
printf("\nPrinting List: \n");
printList(head);
printf("\n\nPrinting in order\n");
printInorder(leaf);
printf("\n\nPrinting Pre order\n");
printPreorder(leaf);
printf("\n\nPrinting Post order\n");
printPostorder(leaf);
head = freeList(head);
freeTree(leaf);
head = NULL;
return 0;
}

Answer 1

branch *leaf; is not initialized. Your code expects leaf pointers to be NULL. Try branch *leaf = NULL;
Also, it looks like freeList frees head twice which is undefined behavior.