Add option to send data over a tcp socket

This reducec the dropbear cpu usage to basically
nothing, since the traffic does not need encryption
anymore.

This option uses the nc command on the client side.
So this will not work with windows as of now!

src/main.rs

@@ -3,14 +3,29 @@ extern crate anyhow;
 extern crate lz_fear;
 
 use anyhow::{Context, Result};
+use clap::{crate_authors, crate_version, Clap};
 use lz_fear::CompressionSettings;
 
 use std::default::Default;
 use std::fs::File;
-use std::io::{BufRead, BufReader, Read, Seek, SeekFrom};
+use std::io::{BufRead, BufReader, Read, Seek, SeekFrom, Write};
 use std::process::Command;
 
+#[derive(Clap)]
+#[clap(version = crate_version!(), author = crate_authors!())]
+pub struct Opts {
+    #[clap(
+        long,
+        name = "address",
+        short = 'c',
+        about = "Establish a new unsecure connection to send the data to which reduces some load on the reMarkable and improves fps."
+    )]
+    connect: Option<String>,
+}
+
 fn main() -> Result<()> {
+    let ref opts: Opts = Opts::parse();
+
     let version = remarkable_version()?;
     let streamer = if version == "reMarkable 1.0\n" {
         let width = 1408;
@@ -33,8 +48,18 @@ fn main() -> Result<()> {
         ))?
     };
 
+    let stdout = std::io::stdout();
+    let data_target: Box<dyn Write> = if let Some(ref address) = opts.connect {
+        eprintln!("[rM] Sending stream to {} (instead of stdout)", address);
+        let conn = std::net::TcpStream::connect(address)?;
+        conn.set_write_timeout(Some(std::time::Duration::from_secs(3)))?;
+        Box::new(conn)
+    } else {
+        Box::new(stdout.lock())
+    };
+
     let lz4: CompressionSettings = Default::default();
-    lz4.compress(streamer, std::io::stdout().lock())
+    lz4.compress(streamer, data_target)
         .context("Error while compressing framebuffer stream")
 }