diff options
Diffstat (limited to 'zellij-server/src/pty.rs')
-rw-r--r-- | zellij-server/src/pty.rs | 160 |
1 files changed, 70 insertions, 90 deletions
diff --git a/zellij-server/src/pty.rs b/zellij-server/src/pty.rs index ecaef460a..803c04248 100644 --- a/zellij-server/src/pty.rs +++ b/zellij-server/src/pty.rs @@ -1,16 +1,14 @@ -use zellij_utils::{async_std, nix}; +use zellij_utils::async_std; -use async_std::stream::*; -use async_std::task; -use async_std::task::*; +use async_std::future::timeout as async_timeout; +use async_std::task::{self, JoinHandle}; use std::collections::HashMap; use std::os::unix::io::RawFd; use std::path::PathBuf; -use std::pin::*; use std::time::{Duration, Instant}; use crate::{ - os_input_output::{Pid, ServerOsApi}, + os_input_output::{AsyncReader, Pid, ServerOsApi}, panes::PaneId, screen::ScreenInstruction, thread_bus::{Bus, ThreadSenders}, @@ -23,52 +21,6 @@ use zellij_utils::{ logging::debug_to_file, }; -pub struct ReadFromPid { - pid: RawFd, - os_input: Box<dyn ServerOsApi>, -} - -impl ReadFromPid { - pub fn new(pid: &RawFd, os_input: Box<dyn ServerOsApi>) -> ReadFromPid { - ReadFromPid { - pid: *pid, - os_input, - } - } -} - -impl Stream for ReadFromPid { - type Item = Vec<u8>; - fn poll_next(self: Pin<&mut Self>, _cx: &mut Context<'_>) -> Poll<Option<Self::Item>> { - let mut read_buffer = [0; 65535]; - let pid = self.pid; - let read_result = &self.os_input.read_from_tty_stdout(pid, &mut read_buffer); - match read_result { - Ok(res) => { - if *res == 0 { - // indicates end of file - Poll::Ready(None) - } else { - let res = Some(read_buffer[..*res].to_vec()); - Poll::Ready(res) - } - } - Err(e) => { - match e { - nix::Error::Sys(errno) => { - if *errno == nix::errno::Errno::EAGAIN { - Poll::Ready(Some(vec![])) // TODO: better with timeout waker somehow - } else { - Poll::Ready(None) - } - } - _ => Poll::Ready(None), - } - } - } - } -} - pub type VteBytes = Vec<u8>; /// Instructions related to PTYs (pseudoterminals). @@ -160,6 +112,42 @@ pub(crate) fn pty_thread_main(mut pty: Pty, maybe_layout: Option<Layout>) { } } +enum ReadResult { + Ok(usize), + Timeout, + Err(std::io::Error), +} + +impl From<std::io::Result<usize>> for ReadResult { + fn from(e: std::io::Result<usize>) -> ReadResult { + match e { + Err(e) => ReadResult::Err(e), + Ok(n) => ReadResult::Ok(n), + } + } +} + +async fn deadline_read( + reader: &mut dyn AsyncReader, + deadline: Option<Instant>, + buf: &mut [u8], +) -> ReadResult { + if let Some(deadline) = deadline { + let timeout = deadline.checked_duration_since(Instant::now()); + if let Some(timeout) = timeout { + match async_timeout(timeout, reader.read(buf)).await { + Ok(res) => res.into(), + _ => ReadResult::Timeout, + } + } else { + // deadline has already elapsed + ReadResult::Timeout + } + } else { + reader.read(buf).await.into() + } +} + fn stream_terminal_bytes( pid: RawFd, senders: ThreadSenders, @@ -170,50 +158,42 @@ fn stream_terminal_bytes( task::spawn({ async move { err_ctx.add_call(ContextType::AsyncTask); - let mut terminal_bytes = ReadFromPid::new(&pid, os_input); - let mut last_byte_receive_time: Option<Instant> = None; - let mut pending_render = false; - let max_render_pause = Duration::from_millis(30); + // After a successful read, we keep on reading additional data up to a duration of + // `render_pause`. This is in order to batch up PtyBytes before rendering them. + // Once `render_deadline` has elapsed, we send Render. + let render_pause = Duration::from_millis(30); + let mut render_deadline = None; - while let Some(bytes) = terminal_bytes.next().await { - let bytes_is_empty = bytes.is_empty(); - if debug { - debug_to_file(&bytes, pid).unwrap(); - } - if !bytes_is_empty { - let _ = senders.send_to_screen(ScreenInstruction::PtyBytes(pid, bytes)); - // for UX reasons, if we got something on the wire, we only send the render notice if: - // 1. there aren't any more bytes on the wire afterwards - // 2. a certain period (currently 30ms) has elapsed since the last render - // (otherwise if we get a large amount of data, the display would hang - // until it's done) - // 3. the stream has ended, and so we render 1 last time - match last_byte_receive_time.as_mut() { - Some(receive_time) => { - if receive_time.elapsed() > max_render_pause { - pending_render = false; - let _ = senders.send_to_screen(ScreenInstruction::Render); - last_byte_receive_time = Some(Instant::now()); - } else { - pending_render = true; - } - } - None => { - last_byte_receive_time = Some(Instant::now()); - pending_render = true; - } - }; - } else { - if pending_render { - pending_render = false; + let mut buf = [0u8; 65536]; + let mut async_reader = os_input.async_file_reader(pid); + loop { + match deadline_read(async_reader.as_mut(), render_deadline, &mut buf).await { + ReadResult::Ok(0) | ReadResult::Err(_) => break, // EOF or error + ReadResult::Timeout => { let _ = senders.send_to_screen(ScreenInstruction::Render); + // next read does not need a deadline as we just rendered everything + render_deadline = None; + + // yield so Screen thread has some time to render before send additional + // PtyBytes. + task::sleep(Duration::from_millis(10)).await; + } + ReadResult::Ok(n_bytes) => { + let bytes = &buf[..n_bytes]; + if debug { + let _ = debug_to_file(bytes, pid); + } + let _ = senders + .send_to_screen(ScreenInstruction::PtyBytes(pid, bytes.to_vec())); + // if we already have a render_deadline we keep it, otherwise we set it + // to the duration of `render_pause`. + render_deadline.get_or_insert(Instant::now() + render_pause); } - last_byte_receive_time = None; - task::sleep(::std::time::Duration::from_millis(10)).await; } } - senders.send_to_screen(ScreenInstruction::Render).unwrap(); + let _ = senders.send_to_screen(ScreenInstruction::Render); + #[cfg(not(any(feature = "test", test)))] // this is a little hacky, and is because the tests end the file as soon as // we read everything, rather than hanging until there is new data |