static void *next_fit(size_t asize)
{
    void *bp  = last_block;
    int wraps = 0;

    while(GET_SIZE(HDRP(bp)) > 0){

        if(wraps > 0 && bp == last_block) // We went through the whole thing
                return NULL;

        if(!GET_ALLOC(HDRP(bp) && (asize <= GET_SIZE(HDRP(bp))) {
                last_block = bp;
                return bp
        }

       bp = NEXT_BLKP(bp);
       if(GET_SIZE(HDRP(bp)) <= 0){
        // We hit the end, need wrap around
                bp = heap_listp;
                wraps++;
       } // end if
    } // end while
} // end next_fit