Refactor: Split pty and shell out of channel

src/channel.rs

@@ -1,12 +1,14 @@
-use std::fs::{File, OpenOptions};
-use std::io::{self, Read, Write};
-use std::os::unix::io::{FromRawFd, IntoRawFd, RawFd};
-use std::os::unix::process::CommandExt;
-use std::path::PathBuf;
-use std::process::{self, Stdio};
-use std::thread::{self, JoinHandle};
+mod pty;
+mod shell;
 
-use crate::sys;
+use std::fs::File;
+use std::io::{self, Write};
+use std::os::unix::io::RawFd;
+use std::path::PathBuf;
+use std::process;
+use std::thread::JoinHandle;
+
+pub use pty::PtyConfig;
 
 pub type ChannelId = u32;
 
@@ -25,23 +27,18 @@ pub struct Channel {
 
 #[derive(Debug)]
 pub enum ChannelRequest {
-    Pty {
-        term: String,
-        chars: u16,
-        rows: u16,
-        pixel_width: u16,
-        pixel_height: u16,
-        modes: Vec<u8>,
-    },
+    Pty(PtyConfig),
     Shell,
 }
 
 impl Channel {
     pub fn new(
-        id: ChannelId, peer_id: ChannelId, peer_window_size: u32,
-        max_packet_size: u32
-    ) -> Channel {
-        Channel {
+        id: ChannelId,
+        peer_id: ChannelId,
+        peer_window_size: u32,
+        max_packet_size: u32,
+    ) -> Self {
+        Self {
             id,
             peer_id,
             process: None,
@@ -66,99 +63,19 @@ impl Channel {
         self.max_packet_size
     }
 
-    pub fn request(&mut self, request: ChannelRequest) {
-        match request
-        {
-            ChannelRequest::Pty {
-                chars,
-                rows,
-                pixel_width,
-                pixel_height,
-                ..
-            } => {
-                let (master_fd, tty_path) = sys::getpty();
-
-                sys::set_winsize(
-                    master_fd,
-                    chars,
-                    rows,
-                    pixel_width,
-                    pixel_height,
-                );
-
-                self.read_thread = Some(thread::spawn(move || {
-                    #[cfg(target_os = "redox")]
-                    let master2 = unsafe { syscall::dup(master_fd as usize, &[]).unwrap_or(!0) };
-                    #[cfg(not(target_os = "redox"))]
-                    let master2 = unsafe { libc::dup(master_fd) };
-
-                    println!("dup result: {}", master2 as u32);
-                    let mut master = unsafe { File::from_raw_fd(master2 as i32) };
-                    loop {
-                        use std::str::from_utf8_unchecked;
-                        let mut buf = [0; 4096];
-                        let count = master.read(&mut buf).unwrap();
-                        // This is weird.
-                        // An error is thrown&unwrapped here (panic)
-                        // but yet it continues to function properly
-                        if count == 0 {
-                            break;
-                        }
-                        println!("Read: {}", unsafe {
-                            from_utf8_unchecked(&buf[0..count])
-                        });
-                    }
-
-                    println!("Quitting read thread.");
-                }));
-
-                self.pty = Some((master_fd, tty_path));
-                self.master = Some(unsafe { File::from_raw_fd(master_fd) });
-            }
-            ChannelRequest::Shell => {
-                if let Some((_, tty_path)) = self.pty.as_ref() {
-                    let stdin = OpenOptions::new()
-                        .read(true)
-                        .write(true)
-                        .open(tty_path)
-                        .unwrap()
-                        .into_raw_fd();
-
-                    let stdout = OpenOptions::new()
-                        .read(true)
-                        .write(true)
-                        .open(tty_path)
-                        .unwrap()
-                        .into_raw_fd();
-
-                    let stderr = OpenOptions::new()
-                        .read(true)
-                        .write(true)
-                        .open(tty_path)
-                        .unwrap()
-                        .into_raw_fd();
-
-                    unsafe {
-                        process::Command::new("login")
-                            .stdin(Stdio::from_raw_fd(stdin))
-                            .stdout(Stdio::from_raw_fd(stdout))
-                            .stderr(Stdio::from_raw_fd(stderr))
-                            .pre_exec(sys::before_exec)
-                        }
-                        .spawn()
-                        .unwrap();
-                }
-            }
+    pub fn handle_request(&mut self, request: ChannelRequest) {
+        match request {
+            ChannelRequest::Pty(ref pty) => self.setup_tty(pty),
+            ChannelRequest::Shell => self.setup_shell(),
         }
         debug!("Channel Request: {:?}", request);
     }
 
-    pub fn data(&mut self, data: &[u8]) -> io::Result<()> {
+    pub fn write_data(&mut self, data: &[u8]) -> io::Result<()> {
         if let Some(ref mut master) = self.master {
             master.write_all(data)?;
             master.flush()
-        }
-        else {
+        } else {
             Ok(())
         }
     }

src/channel/pty.rs

@@ -0,0 +1,76 @@
+use std::{fs::File, io::Read, os::fd::FromRawFd, thread};
+
+use crate::sys;
+
+use super::Channel;
+
+#[derive(Debug)]
+pub struct PtyConfig {
+    pub term: String,
+    pub chars: u16,
+    pub rows: u16,
+    pub pixel_width: u16,
+    pub pixel_height: u16,
+    pub modes: Vec<u8>,
+}
+
+impl Channel {
+    /// Allocates and sets up new PTY.
+    /// TODO: consider what to do if there already is a PTY.
+    ///
+    /// Also does incorrect error handling internally
+    /// on I/O errors and occurs if a process exits.
+    pub fn setup_tty(
+        &mut self,
+        PtyConfig {
+            term,
+            chars,
+            rows,
+            pixel_width,
+            pixel_height,
+            modes,
+        }: &PtyConfig,
+    ) {
+        let (master_fd, tty_path) = sys::getpty();
+
+        sys::set_winsize(master_fd, *chars, *rows, *pixel_width, *pixel_height);
+
+        self.read_thread = Some(thread::spawn(move || {
+            #[cfg(target_os = "redox")]
+            let master2 =
+                unsafe { syscall::dup(master_fd as usize, &[]).unwrap_or(!0) };
+            #[cfg(not(target_os = "redox"))]
+            let master2 = unsafe { libc::dup(master_fd) };
+
+            println!("dup result: {}", master2 as u32);
+            let mut master = unsafe { File::from_raw_fd(master2 as i32) };
+            loop {
+                use std::str::from_utf8_unchecked;
+
+                let mut buf = [0; 4096];
+                let count = match master.read(&mut buf) {
+                    Ok(o) => o,
+                    Err(e) => {
+                        warn!("Error occured, ignoring: {}", e);
+                        1 // TODO
+                    },
+                };
+
+                // This is weird.
+                // An error is thrown&unwrapped here (panic)
+                // but yet it continues to function properly
+                if count == 0 {
+                    break;
+                }
+                println!("Read: {}", unsafe {
+                    from_utf8_unchecked(&buf[0..count])
+                });
+            }
+
+            println!("Quitting read thread.");
+        }));
+
+        self.pty = Some((master_fd, tty_path));
+        self.master = Some(unsafe { File::from_raw_fd(master_fd) });
+    }
+}

src/channel/shell.rs

@@ -0,0 +1,49 @@
+use std::{
+    fs::OpenOptions,
+    os::{
+        fd::{FromRawFd, IntoRawFd},
+        unix::process::CommandExt,
+    },
+    process::{self, Stdio},
+};
+
+use crate::sys;
+
+use super::Channel;
+
+impl Channel {
+    pub fn setup_shell(&self) {
+        if let Some((_, tty_path)) = self.pty.as_ref() {
+            let stdin = OpenOptions::new()
+                .read(true)
+                .write(true)
+                .open(tty_path)
+                .unwrap()
+                .into_raw_fd();
+
+            let stdout = OpenOptions::new()
+                .read(true)
+                .write(true)
+                .open(tty_path)
+                .unwrap()
+                .into_raw_fd();
+
+            let stderr = OpenOptions::new()
+                .read(true)
+                .write(true)
+                .open(tty_path)
+                .unwrap()
+                .into_raw_fd();
+
+            unsafe {
+                process::Command::new("login")
+                    .stdin(Stdio::from_raw_fd(stdin))
+                    .stdout(Stdio::from_raw_fd(stdout))
+                    .stderr(Stdio::from_raw_fd(stderr))
+                    .pre_exec(sys::before_exec)
+            }
+            .spawn()
+            .unwrap();
+        }
+    }
+}

src/connection.rs

@@ -4,7 +4,7 @@ use std::sync::Arc;
 
 use rand::distributions::Standard;
 
-use crate::channel::{Channel, ChannelId, ChannelRequest};
+use crate::channel::{Channel, ChannelId, ChannelRequest, PtyConfig};
 use crate::encryption::{AesCtr, Decryptor, Encryption};
 use crate::error::{ConnectionError, ConnectionResult as Result};
 use crate::key_exchange::{KexResult, KeyExchange};
@@ -315,21 +315,21 @@ impl Connection {
         let want_reply = reader.read_bool()?;
 
         let request = match &*name {
-            "pty-req" => Some(ChannelRequest::Pty {
+            "pty-req" => Some(ChannelRequest::Pty(PtyConfig {
                 term: reader.read_utf8()?,
                 chars: reader.read_uint32()? as u16,
                 rows: reader.read_uint32()? as u16,
                 pixel_width: reader.read_uint32()? as u16,
                 pixel_height: reader.read_uint32()? as u16,
                 modes: reader.read_string()?,
-            }),
+            })),
             "shell" => Some(ChannelRequest::Shell),
             _ => None,
         };
 
         if let Some(request) = request {
             let channel = self.channels.get_mut(&channel_id).unwrap();
-            channel.request(request);
+            channel.handle_request(request);
         } else {
             warn!("Unkown channel request {}", name);
         }
@@ -349,7 +349,7 @@ impl Connection {
         let data = reader.read_string()?;
 
         let channel = self.channels.get_mut(&channel_id).unwrap();
-        channel.data(data.as_slice())?;
+        channel.write_data(data.as_slice())?;
 
         Ok(None)
     }