From 9d5bd561419e1145aea81ee820bc3e8405c4fd57 Mon Sep 17 00:00:00 2001
From: Tom Smeding <tom.smeding@gmail.com>
Date: Tue, 13 Oct 2020 21:46:42 +0200
Subject: rust: Server and account command-line arguments

---
 rust/Cargo.toml     |  2 ++
 rust/src/getpass.rs | 65 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 rust/src/main.rs    | 54 ++++++++++++++++++++++++++++++++++++++++----
 3 files changed, 117 insertions(+), 4 deletions(-)
 create mode 100644 rust/src/getpass.rs

diff --git a/rust/Cargo.toml b/rust/Cargo.toml
index 869baeb..bd0e51c 100644
--- a/rust/Cargo.toml
+++ b/rust/Cargo.toml
@@ -14,3 +14,5 @@ unicode-width = "^0.1.8"
 users = "0.10"
 dirs = "3.0"
 rand = "0.7"
+argparse = "0.2"
+libc = "^0.2.79"
diff --git a/rust/src/getpass.rs b/rust/src/getpass.rs
new file mode 100644
index 0000000..f40da0e
--- /dev/null
+++ b/rust/src/getpass.rs
@@ -0,0 +1,65 @@
+extern crate libc;
+
+use std::io::{self, Write};
+use std::mem;
+use std::str;
+
+fn error_checker(ret: i32) -> io::Result<()> {
+    if ret == 0 {
+        Ok(())
+    } else {
+        Err(io::Error::last_os_error())
+    }
+}
+
+fn tcgetattr(fd: i32) -> io::Result<libc::termios> {
+    unsafe {
+        let mut tios: libc::termios = mem::zeroed();
+        error_checker(libc::tcgetattr(fd, &mut tios))?;
+        Ok(tios)
+    }
+}
+
+fn tcsetattr(fd: i32, other_options: i32, tios: &libc::termios) -> io::Result<()> {
+    unsafe {
+        error_checker(libc::tcsetattr(fd, other_options, tios))?;
+        Ok(())
+    }
+}
+
+fn without_echo<T, F: FnOnce() -> io::Result<T>>(f: F) -> io::Result<T> {
+    let tios_old = tcgetattr(0)?;
+
+    let mut tios_new = tios_old;
+    tios_new.c_lflag &= !libc::ECHO;
+    tios_new.c_lflag |= libc::ECHONL;
+
+    match tcsetattr(0, libc::TCSANOW, &tios_new) {
+        Ok(()) => {},
+        Err(e) => {
+            // Just blindly try to reset the terminal, in case something changed
+            let _ = tcsetattr(0, libc::TCSANOW, &tios_old);
+            return Err(e);
+        }
+    }
+
+    let ret = f()?;
+
+    tcsetattr(0, libc::TCSANOW, &tios_old)?;
+
+    Ok(ret)
+}
+
+pub fn get_pass(prompt: &str) -> io::Result<String> {
+    print!("{}", prompt);
+    io::stdout().flush()?;
+
+    without_echo(|| {
+        let mut line = String::new();
+        io::stdin().read_line(&mut line)?;
+        if line.ends_with('\n') {
+            line.pop();
+        }
+        Ok(line)
+    })
+}
diff --git a/rust/src/main.rs b/rust/src/main.rs
index f7a2660..8c7e617 100644
--- a/rust/src/main.rs
+++ b/rust/src/main.rs
@@ -3,6 +3,7 @@ use std::collections::{HashMap, HashSet};
 use std::io::{self, Write};
 use std::sync::{Arc, Mutex};
 use std::convert::TryFrom;
+use argparse::{ArgumentParser, Store, StoreOption};
 use futures::channel::mpsc;
 use futures::stream::StreamExt;
 use once_cell::sync::Lazy;
@@ -22,6 +23,7 @@ mod auth;
 mod bel;
 mod editor;
 mod error;
+mod getpass;
 
 static DEBUG_FILE: Lazy<Mutex<Option<File>>> = Lazy::new(|| {
     Mutex::new(
@@ -624,14 +626,58 @@ async fn pushchan_thread(mut chan: mpsc::Receiver<PushMessage>, app: Arc<App>) {
     }
 }
 
+struct Options {
+    server: String,
+    username: Option<String>,
+}
+
+impl Default for Options {
+    fn default() -> Self {
+        Self { server: String::from("127.0.0.1:29538"), username: None }
+    }
+}
+
+fn parse_options() -> Options {
+    let mut options = Options::default();
+    let defserver = options.server.clone();
+    let server_descr = format!("Address (host:port) of tomsg server (default: {})", defserver);
+
+    {
+        let mut ap = ArgumentParser::new();
+        ap.set_description("Simple client for tomsg with auto-generated credentials.");
+
+        ap.refer(&mut options.server)
+            .add_option(&["-s", "--server"], Store, &server_descr)
+            .metavar("ADDR");
+        ap.refer(&mut options.username)
+            .add_option(&["-u", "--user"], StoreOption,
+                        "Username to connect as (if given, will prompt for password on stdin) (default: current system username)")
+            .metavar("USER");
+
+        ap.parse_args_or_exit();
+    }
+    options
+}
+
 async fn async_main() -> io::Result<()> {
-    let addr = ("127.0.0.1", 29538);
-    let (conn, pushchan) = Connection::connect(connection::Type::Plain, addr).await?;
+    let options = parse_options();
+
+    let (conn, pushchan) = Connection::connect(connection::Type::Plain, options.server).await?;
 
     let (user, pass) = auth::get_auth_info()?;
 
-    let user = Word::try_from(user.to_string()).unwrap();
-    let pass = Line::try_from(pass.to_string()).unwrap();
+    let (user, pass) = match options.username {
+        None => (Word::try_from(user.to_string()).unwrap()
+                ,Line::try_from(pass.to_string()).unwrap()),
+        Some(user) => {
+            let pass = getpass::get_pass(&format!("Password for user '{}': ", user))?;
+            if pass.len() == 0 {
+                println!("Cancelled.");
+                std::process::exit(1);
+            }
+            (Word::try_from(user).unwrap(), Line::try_from(pass).unwrap())
+        }
+    };
 
     send_command(&conn, Command::Register { username: user.clone(), password: pass.clone() }).await?;
 
-- 
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