Function generate_stairs_find_room

src/mklev.c:2218–2245

/* find a good room to generate an up or down stairs in */
staticfn struct mkroom *
generate_stairs_find_room(void)
{
    struct mkroom *croom;
    int i, phase, ai;
    int *rmarr;

    if (!svn.nroom)
        return (struct mkroom *) 0;

    rmarr = (int *) alloc(sizeof(int) * svn.nroom);

    for (phase = 2; phase > -1; phase--) {
        ai = 0;
        for (i = 0; i < svn.nroom; i++)
            if (generate_stairs_room_good(&svr.rooms[i], phase))
                rmarr[ai++] = i;
        if (ai > 0) {
            i = rmarr[rn2(ai)];
            free(rmarr);
            return &svr.rooms[i];
        }
    }

    free(rmarr);
    croom = &svr.rooms[rn2(svn.nroom)];
    return croom;
}

/* construct stairs up and down within the same branch,
   up and down in different rooms if possible */