#include "unistd.h"
#include <stddef.h>
#include <stdint.h>

void *__curr_brk = NULL;

void *sbrk(intptr_t increment)
{
    if (!__curr_brk) {
        brk(NULL);
    }

    uintptr_t end = (uintptr_t)__curr_brk + increment;
    void *start = __curr_brk;
    int res = brk((void *)end);

    if (res == -1) {
        return NULL;
    }

    return start;
}