comparison rust/chg/src/uihandler.rs @ 44755:4b0185841058

rust-chg: do not terminate tokio runtime until pager exits

We no longer need to spawn a task just to keep the pager handle. The pager
handle can be held by ChgUiHandler since the handler itself is not consumed
and recreated across async calls.

Differential Revision: https://phab.mercurial-scm.org/D8449

44754:9fc9526e283a

use std::io;
use std::os::unix::io::AsRawFd;
use std::os::unix::process::ExitStatusExt;
use std::process::Stdio;
use tokio;
use tokio::process::{ChildStdin, Command};

use crate::message::CommandSpec;
use crate::procutil;

/// Callback to process shell command requests received from server.

    /// Returns command exit code (positive) or signal number (negative).
    async fn run_system(&mut self, spec: &CommandSpec) -> io::Result<i32>;
}

/// Default cHg implementation to process requests received from server.
pub struct ChgUiHandler {}

impl ChgUiHandler {
    pub fn new() -> ChgUiHandler {
        ChgUiHandler {}
    }
}

#[async_trait]
impl SystemHandler for ChgUiHandler {

        procutil::set_blocking_fd(pin.as_raw_fd())?;
        // TODO: if pager exits, notify the server with SIGPIPE immediately.
        // otherwise the server won't get SIGPIPE if it does not write
        // anything. (issue5278)
        // kill(peerpid, SIGPIPE);
        tokio::spawn(async { pager.await }); // just ignore errors
        Ok(pin)
    }

    async fn run_system(&mut self, spec: &CommandSpec) -> io::Result<i32> {
        let status = new_shell_command(&spec).spawn()?.await?;

44755:4b0185841058

use std::io;
use std::os::unix::io::AsRawFd;
use std::os::unix::process::ExitStatusExt;
use std::process::Stdio;
use tokio;
use tokio::process::{Child, ChildStdin, Command};

use crate::message::CommandSpec;
use crate::procutil;

/// Callback to process shell command requests received from server.

    /// Returns command exit code (positive) or signal number (negative).
    async fn run_system(&mut self, spec: &CommandSpec) -> io::Result<i32>;
}

/// Default cHg implementation to process requests received from server.
pub struct ChgUiHandler {
    pager: Option<Child>,
}

impl ChgUiHandler {
    pub fn new() -> ChgUiHandler {
        ChgUiHandler { pager: None }
    }

    /// Waits until the pager process exits.
    pub async fn wait_pager(&mut self) -> io::Result<()> {
        if let Some(p) = self.pager.take() {
            p.await?;
        }
        Ok(())
    }
}

#[async_trait]
impl SystemHandler for ChgUiHandler {

        procutil::set_blocking_fd(pin.as_raw_fd())?;
        // TODO: if pager exits, notify the server with SIGPIPE immediately.
        // otherwise the server won't get SIGPIPE if it does not write
        // anything. (issue5278)
        // kill(peerpid, SIGPIPE);
        self.pager = Some(pager);
        Ok(pin)
    }

    async fn run_system(&mut self, spec: &CommandSpec) -> io::Result<i32> {
        let status = new_shell_command(&spec).spawn()?.await?;