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use nix::{convert_ioctl_res, ioctl};
use serde_derive::Deserialize;
use std::env;
use std::fs::File;
use std::io::prelude::*;
use std::net::{SocketAddr, UdpSocket};
use std::os::unix::io::AsRawFd;
use std::time::Duration;
const FIONREAD: u16 = 0x541B;
ioctl!(bad read available with FIONREAD; usize);
#[derive(Debug, Deserialize)]
pub struct Address {
ip: String,
port: u16,
}
#[derive(Debug, Deserialize)]
pub struct Config {
host: Address,
service: Address,
query_file: String,
}
fn configure_client() -> (SocketAddr, SocketAddr, String) {
let args: Vec<String> = env::args().collect();
let config: Config = if args.len() == 2 {
let mut raw = String::new();
let filename = &args[1];
match File::open(filename)
.map(|mut f| f.read_to_string(&mut raw))
.map(|_| toml::from_str(&raw))
{
Ok(toml) => toml.unwrap(),
_ => {
panic!("Couldn't open config file");
}
}
} else {
panic!("No config file");
};
let listen_addr = format!("{}:{}", config.host.ip, config.host.port)
.parse::<SocketAddr>()
.unwrap();
let send_addr = format!("{}:{}", config.service.ip, config.service.port)
.parse::<SocketAddr>()
.unwrap();
let query: String = {
let mut raw = String::new();
match File::open(config.query_file).map(|mut f| f.read_to_string(&mut raw)) {
Ok(_) => raw,
_ => {
println!("Using default query");
"{ping}".to_owned()
}
}
};
(listen_addr, send_addr, query)
}
fn main() {
let (client_addr, service_addr, query) = configure_client();
let socket = match UdpSocket::bind(client_addr) {
Ok(sock) => {
println!("Bound socket to {}", client_addr);
sock
}
Err(err) => {
println!("Could not bind: {}", err);
return;
}
};
let result = socket.send_to(&query.as_bytes(), &service_addr);
match result {
Ok(amt) => println!("Sent {} bytes", amt),
Err(err) => {
println!("Write error: {}", err);
return;
}
}
socket.set_read_timeout(Some(Duration::new(1, 0))).unwrap();
let mut buf: [u8; 1] = [0];
let result = socket.peek_from(&mut buf);
if let Err(err) = result {
println!("Read error: {}", err);
return;
}
let mut len: usize = 0;
unsafe {
match available(socket.as_raw_fd(), &mut len) {
Ok(_) => {}
Err(err) => {
println!("Failed to read bytes available: {}", err);
return;
}
}
}
let mut buf = vec![0u8; len].into_boxed_slice();
let result = socket.recv_from(&mut buf);
match result {
Ok((amt, src)) => {
println!("Received {} bytes from {}", amt, src);
let mut v: serde_json::Value = serde_json::from_slice(&buf[0..(amt)]).unwrap();
match serde_json::from_value::<String>(v["data"].clone()) {
Ok(msg) => {
v = serde_json::from_str(&msg).unwrap_or_default();
}
_ => println!("Errors returned from query"),
}
println!("{}", serde_json::to_string_pretty(&v).unwrap());
}
Err(err) => {
println!("Read error: {}", err);
return;
}
}
}