net2-rs unchecked conversions

git grep -E ' as [ui](size|[0-9]{1,2})' -- '*.rs'

src/ext.rs:        assert_eq!(len as usize, mem::size_of::<T>());
src/ext.rs:        Ok(Some((secs as u32) * 1000))
src/ext.rs:        Ok(Some((secs as u32) * 1000))
src/ext.rs:            .map(|b| b as u32)
src/ext.rs:        Some(dur.tv_sec as u32 * 1000 + dur.tv_usec as u32 / 1000)
src/ext.rs:        Some(Duration::from_secs(linger_opt.l_linger as u64))
src/ext.rs:                l_linger: d.as_secs() as u16,
src/ext.rs:    Duration::new((ms as u64) / 1000, (ms as u32) % 1000 * 1_000_000)
src/ext.rs:    (dur.as_secs() as u32 * 1000) + (dur.subsec_nanos() / 1_000_000)
src/ext.rs:    n as usize
src/ext.rs:        Some(io::Error::from_raw_os_error(n as i32))
src/ext.rs:            .map(|b| b as u32)
src/ext.rs:            .map(|b| b as u32)
src/ext.rs:        get_opt::<c_int>(self.as_sock(), v(IPPROTO_IPV6), IPV6_MULTICAST_IF).map(|b| b as u32)
src/ext.rs:            .map(|b| b as u32)
src/ext.rs:            .map(|b| b as u32)
src/ext.rs:            ::cvt(write(self.as_sock() as c_int, buf.as_ptr() as *const _, buf.len())).map(|n| n as usize)
src/ext.rs:            ::cvt(send(self.as_sock() as c_int, buf.as_ptr() as *const _, buf.len(), 0)).map(|n| n as usize)
src/ext.rs:        let len = ::std::cmp::min(buf.len(), c_int::max_value() as usize);
src/ext.rs:                .map(|n| n as usize)
src/ext.rs:                .map(|n| n as usize)
src/ext.rs:                .map(|n| n as usize)
src/ext.rs:        let len = ::std::cmp::min(buf.len(), c_int::max_value() as usize);
src/ext.rs:                .map(|n| n as usize)
src/ext.rs:        s_addr: ::hton(((oct[0] as u32) << 24) |
src/ext.rs:                       ((oct[1] as u32) << 16) |
src/ext.rs:                       ((oct[2] as u32) <<  8) |
src/ext.rs:                       ((oct[3] as u32) <<  0)),
src/ext.rs:        s_addr: ::hton(((oct[0] as u32) << 24) |
src/ext.rs:                       ((oct[1] as u32) << 16) |
src/ext.rs:                       ((oct[2] as u32) <<  8) |
src/ext.rs:                       ((oct[3] as u32) <<  0)),
src/ext.rs:        *S_un.S_addr_mut() = ::hton(((oct[0] as u32) << 24) |
src/ext.rs:                                ((oct[1] as u32) << 16) |
src/ext.rs:                                ((oct[2] as u32) <<  8) |
src/ext.rs:                                ((oct[3] as u32) <<  0));
src/ext.rs:    let a: u8 = (h_addr >> 24) as u8;
src/ext.rs:    let b: u8 = (h_addr >> 16) as u8;
src/ext.rs:    let c: u8 = (h_addr >> 8) as u8;
src/ext.rs:    let d: u8 = (h_addr >> 0) as u8;
src/ext.rs:        (seg[0] >> 8) as u8,
src/ext.rs:        (seg[0] >> 0) as u8,
src/ext.rs:        (seg[1] >> 8) as u8,
src/ext.rs:        (seg[1] >> 0) as u8,
src/ext.rs:        (seg[2] >> 8) as u8,
src/ext.rs:        (seg[2] >> 0) as u8,
src/ext.rs:        (seg[3] >> 8) as u8,
src/ext.rs:        (seg[3] >> 0) as u8,
src/ext.rs:        (seg[4] >> 8) as u8,
src/ext.rs:        (seg[4] >> 0) as u8,
src/ext.rs:        (seg[5] >> 8) as u8,
src/ext.rs:        (seg[5] >> 0) as u8,
src/ext.rs:        (seg[6] >> 8) as u8,
src/ext.rs:        (seg[6] >> 0) as u8,
src/ext.rs:        (seg[7] >> 8) as u8,
src/ext.rs:        (seg[7] >> 0) as u8,
src/ext.rs:            .map(|b| b as u32)
src/socket.rs:                assert!(len as usize >= mem::size_of::<c::sockaddr_in>());
src/socket.rs:                let ip = Ipv4Addr::new((bits >> 24) as u8,
src/socket.rs:                                       (bits >> 16) as u8,
src/socket.rs:                                       (bits >> 8) as u8,
src/socket.rs:                                       bits as u8);
src/socket.rs:                assert!(len as usize >= mem::size_of::<c::sockaddr_in6>());
src/socket.rs:                    (arr[0] as u16) << 8 | (arr[1] as u16),
src/socket.rs:                    (arr[2] as u16) << 8 | (arr[3] as u16),
src/socket.rs:                    (arr[4] as u16) << 8 | (arr[5] as u16),
src/socket.rs:                    (arr[6] as u16) << 8 | (arr[7] as u16),
src/socket.rs:                    (arr[8] as u16) << 8 | (arr[9] as u16),
src/socket.rs:                    (arr[10] as u16) << 8 | (arr[11] as u16),
src/socket.rs:                    (arr[12] as u16) << 8 | (arr[13] as u16),
src/socket.rs:                    (arr[14] as u16) << 8 | (arr[15] as u16),
src/sys/redox/impls.rs:        self.as_inner().borrow().as_ref().unwrap().as_inner().raw() as usize
src/sys/redox/impls.rs:        self.as_inner().borrow().as_ref().unwrap().as_inner().raw() as usize
src/sys/redox/mod.rs:        unsafe { TcpListener::from_raw_fd(self.into_fd() as usize) }
src/sys/redox/mod.rs:        unsafe { TcpStream::from_raw_fd(self.into_fd() as usize) }
src/sys/redox/mod.rs:        unsafe { UdpSocket::from_raw_fd(self.into_fd() as usize) }