Method randbits

src/random.h:184–197

Generate a random (bits)-bit integer. */

    /** Generate a random (bits)-bit integer. */
    uint64_t randbits(int bits) noexcept
    {
        if (bits == 0) {
            return 0;
        } else if (bits > 32) {
            return rand64() >> (64 - bits);
        } else {
            if (bitbuf_size < bits) FillBitBuffer();
            uint64_t ret = bitbuf & (~(uint64_t)0 >> (64 - bits));
            bitbuf >>= bits;
            bitbuf_size -= bits;
            return ret;
        }
    }

    /** Generate a random integer in the range [0..range).
     * Precondition: range > 0.