node.c

#include "node.h"
#include <stdio.h>
#define META_SIZE sizeof(struct node)

/*Creates a node at the given address with the given size*/
struct node * new_node(void* address, size_t size){
    struct node *p ;
    p = (struct node*) address;
    /*Point below the node*/
    p->chunk_pointer = p + 1;
    p->size = size;
    p->free = 0; 

    return (struct node*) address;
}

/*Adds a node to the end of a list, given its root*/
void add_end(struct node* root, struct node* end_node){
    struct node *current = root;
    while(current-> next != NULL)current = current->next;
    current->next = end_node;
    end_node->prev = current;
    end_node->next = NULL;
}

/*Adds a node before a given node*/
void addHere(struct node* here, struct node* add_node){
    if(here->prev != NULL)
    here->prev->next = add_node;
    add_node->prev = here->prev;
    here->prev = add_node;
    add_node->next = here;
}

/*Adds a node after a given node*/
void add_after(struct node* here, struct node* add_node){
    if(here->next == NULL){
        here->next = add_node;
        add_node->prev = here;
        add_node->next = NULL;
    }else{
        add_node->next = here->next;
        add_node->prev = here;
        here->next->prev = add_node;
        here->next = add_node;
    }
}

/*Adds a node first in a list, given its root*/
struct node* add_first(struct node* root, struct node* add_node){
    root->prev = add_node;
    add_node->next = root;
    add_node->prev = NULL;
    return add_node;
}

/*Removes the next node given a node*/
void remove_next(struct node* here){
    struct node* next = here->next;
    if(here->next == NULL) return;

    if(here->next->next == NULL){
        here->next->prev = NULL;
        here->next = NULL;
    }else{
        next->next->prev = here;
        next->prev = NULL;
        here->next = next->next;
        next->next = NULL;
    }
}

/*Removes the first node, given the root*/
struct node* remove_first(struct node* root){
    struct node* temp;
    if(root->next == NULL) return NULL;

    temp = root->next;
    temp->prev = NULL;
    root->next = NULL;
    return temp;
}