implement a visitor function

[abdullahemad12]

Task

implement cbt_visit_all() function that takes a pointer to a function and call this function on all the objects in all the nodes of the tree.

Method

The function will traverse the whole tree starting from the root until it reaches all the leaves and will call the visitor function on all the objects saves in the nodes of the tree.

Prototype

/**
  * crabtree_t* , void (*) (void *)  -> void
  * EFFECTS: Calls the visitor function on every object pointer stored in the tree
  * MODIFIES: cranbtree.objects
  * REQUIRES: The  visitor function to take a void* as an argument and to return nothing 
  * PARAMETERS: 
  * - cranbtree_t* cbt: the tree to be traversed
  * - void (* visitor) (void *): the function that will be invoked on every object in the tree  
  */
void cbt_visit_all(cranbtree_t* cbt, void (* visitor) (void *))

Where to code

• the interface function will go to src/cranbtree.c
• any helpers will go to src/lib/visit.c

Tests

1. Test the visit function on an empty tree Error reporting in cbt_visit_all #24
2. Test the visit function on a tree with a NULL visitor pointer Error reporting in cbt_visit_all #24
3. Test the visit function on an a large tree