use std::mem::size_of; use std::net::UdpSocket; use clap::Parser; use num_derive::FromPrimitive; use crate::DisplayCommand::CmdBitmapLinearWin; #[derive(Parser, Debug)] struct Cli { #[arg(long = "bind", default_value = "0.0.0.0:2342")] bind: String, } #[derive(Debug, FromPrimitive)] enum DisplayCommand { CmdClear = 0x0002, CmdCp437data = 0x0003, CmdCharBrightness = 0x0005, CmdBrightness = 0x0007, CmdHardReset = 0x000b, CmdFadeOut = 0x000d, CmdBitmapLegacy = 0x0010, CmdBitmapLinear = 0x0012, CmdBitmapLinearWin = 0x0013, CmdBitmapLinearAnd = 0x0014, CmdBitmapLinearOr = 0x0015, CmdBitmapLinearXor = 0x0016, } #[repr(u16)] enum DisplaySubcommand { SubCmdBitmapNormal = 0x0, SubCmdBitmapCompressZ = 0x677a, SubCmdBitmapCompressBz = 0x627a, SubCmdBitmapCompressLz = 0x6c7a, SubCmdBitmapCompressZs = 0x7a73, } #[repr(C)] #[derive(Debug)] struct HdrWindow { command: DisplayCommand, x: u16, y: u16, w: u16, h: u16, } #[repr(C)] struct HdrBitmap { command: DisplayCommand, offset: u16, length: u16, subcommand: u16, reserved: u16, } fn main() -> std::io::Result<()> { assert_eq!(size_of::<HdrWindow>(), 10, "invalid struct size"); let cli = Cli::parse(); println!("running with args: {:?}", cli); let socket = UdpSocket::bind(cli.bind)?; let mut buf = [0; 8985]; loop { let (amount, source) = socket.recv_from(&mut buf)?; let received = &mut buf[..amount]; if amount < size_of::<HdrWindow>() { println!("received a packet that is too small from {:?}", source); continue; } let header: HdrWindow = HdrWindow { command: num::FromPrimitive::from_u16(u16::from_be(unsafe { std::ptr::read(received[0..=1].as_ptr() as *const u16) })) .unwrap(), x: u16::from_be(unsafe { std::ptr::read(received[2..=3].as_ptr() as *const u16) }), y: u16::from_be(unsafe { std::ptr::read(received[4..=5].as_ptr() as *const u16) }), w: u16::from_be(unsafe { std::ptr::read(received[6..=7].as_ptr() as *const u16) }), h: u16::from_be(unsafe { std::ptr::read(received[8..=9].as_ptr() as *const u16) }), }; let payload = &received[10..]; println!( "received from {:?}: {:?} (and {} bytes of payload)", source, header, payload.len() ); if !matches!(header.command, CmdBitmapLinearWin) { println!( "command {:?} sent by {:?} not implemented yet", header.command, source ); continue; } let expected_size = (header.w * header.h) as usize; if expected_size != payload.len() { println!( "expected a payload length of {} but got {} from {:?}", expected_size, payload.len(), source ); continue; } for y in 0..header.h { for byte_x in 0..header.w { let byte_index = (y * header.w + byte_x) as usize; let byte = payload[byte_index]; for bitmask in [1, 2, 4, 8, 16, 32, 64, 128] { let char = if byte & bitmask == bitmask {'█'} else {' '}; print!("{}", char); } } println!(); } } }