#include <stdlib.h>
#include <stdio.h>

#include "finalize.h"

struct Node
{
    struct Node *next;
    void (*callback)(void);
};

static struct Node *list;

void
finalizeRegister(void (*callback)(void))
{
    struct Node *n = malloc(sizeof(*n));
    if (!n) {
        fprintf(stderr, "finalizeRegister: out of memory\n");
        finalizeExit(1);
    }

    // initialize list node and prepend to list
    n->next = list;
    n->callback = callback;
    list = n;
}

void
finalize(void)
{
    for (struct Node *n = list, *next; n; n = next) {
        // keep copy of pointer to next node
        next = n->next;

        // callback
        n->callback();

        // free node itself
        free(n);
    }
}

void
finalizeExit(int code)
{
    finalize();
    exit(code);
}