From 2fee948de10d28a4b09ac4188d6967373bac5cac Mon Sep 17 00:00:00 2001
From: andromeda <andromeda@lenovo>
Date: Sat, 17 Jan 2026 00:40:22 +0100
Subject: [PATCH] nonblocking, good stuff w/ vte :)

---
 Cargo.lock  | 10 ++++++++++
 Cargo.toml  |  1 +
 src/main.rs | 47 +++++++++++++++++++++++++++++------------------
 3 files changed, 40 insertions(+), 18 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index ade81cc..4527a6f 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -50,11 +50,21 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "nonblock"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "51c7a4f22e5f2e2bd805d6ab56f1ae87eb1815673e1b452048896fb687a8a3d4"
+dependencies = [
+ "libc",
+]
+
 [[package]]
 name = "rustty"
 version = "0.1.0"
 dependencies = [
  "nix",
+ "nonblock",
  "vte",
 ]
 
diff --git a/Cargo.toml b/Cargo.toml
index f4b7be2..f282520 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -5,4 +5,5 @@ edition = "2024"
 
 [dependencies]
 nix = {default-features = false, features=["term","process","fs"], version="0.30.1"}
+nonblock = "0.2.0"
 vte = "0.15.0"
diff --git a/src/main.rs b/src/main.rs
index 05fb64e..6e680f8 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,14 +1,16 @@
+use nix::fcntl::{fcntl, F_GETFL, F_SETFL, OFlag};
 use nix::pty::{ForkptyResult, forkpty, PtyMaster};
-use nix::unistd::read;
+use nix::unistd::{execv, read, write};
 
-use std::vec::Vec;
-use std::io::{self, Read, Write};
-use std::process::Command;
-use std::thread;
-use std::time::Duration;
+use nonblock::NonBlockingReader;
+
+use std::vec;
+use std::ffi::CString;
+use std::io;
 
 use vte::{Params, Parser, Perform};
 
+// yoinked form vte docs
 struct Performer;
 impl Perform for Performer {
     fn print(&mut self, c: char) {
@@ -54,25 +56,35 @@ impl Perform for Performer {
 }
 
 fn main() {
-
     // TODO get rid of hard coded `sh` path
-    let mut pty = spawn_pty("/home/andromeda/.nix-profile/bin/sh").unwrap();
+    let pty = spawn_pty("/home/andromeda/.nix-profile/bin/sh").unwrap();
     println!("{:?}", &pty);
+    let pty_flags = fcntl(&pty, F_GETFL).unwrap();
+    fcntl(&pty, F_SETFL(OFlag::from_bits_truncate(pty_flags) | OFlag::O_NONBLOCK)).unwrap();
 
-    let input = io::stdin();
-    let mut handle = input.lock();
+    let stdin = io::stdin();
+    let mut nb_stdin = NonBlockingReader::from_fd(stdin).unwrap();
 
     let mut statemachine = Parser::new();
     let mut performer = Performer;
     let mut buf = [0u8; 2048];
+    let mut vec: Vec<u8> = vec!();
 
-    while true {
+    loop {
         match read(&pty, &mut buf) {
-            Ok(0) => break,
+            Ok(0) => (),
+            Ok(n) => statemachine.advance(&mut performer, &buf[..n]),
+            Err(_e) => (),
+        };
+        vec.clear();
+        match &nb_stdin.read_available(&mut vec) {
+            Ok(0) => (),
             Ok(n) => {
-                statemachine.advance(&mut performer, &buf[..n]);
+                let un = *n as usize;
+                buf[..un].copy_from_slice(&vec[..un]);
+                let _ = write(&pty, &buf[..un]);
             },
-            Err(_e) => break,
+            Err(e) => println!("error: {:?}", e),
         };
     };
 }
@@ -82,14 +94,13 @@ fn spawn_pty(shell: &str) -> Option<PtyMaster> {
     // SAFETY safe unless os out of PTYs; incredibly unlikely
     match unsafe {forkpty(None, None)} {
         Ok(fork_pty_res) => match fork_pty_res {
-            ForkptyResult::Parent {master, ..} => {
+            ForkptyResult::Parent {child:_, master} => {
+
                 // SAFETY `master` is a valid PtyMaster
                 return Some(unsafe{PtyMaster::from_owned_fd(master)});
             }
             ForkptyResult::Child =>{
-                Command::new(shell).spawn();
-                // TODO come up with an elegant solution
-                thread::sleep(Duration::MAX);
+                let _ = execv::<CString>(&CString::new(shell).unwrap(), &[]);
                 return None;
             }
         },