From 98cc85e2d3f9c1c0576d613dde0b5d9a3c079a85 Mon Sep 17 00:00:00 2001
From: Julian Orth <ju.orth@gmail.com>
Date: Thu, 12 May 2022 21:35:08 +0200
Subject: [PATCH] acceptor: rebase from EventLoop onto AsyncEngine

---
 src/acceptor.rs   | 87 ++++++++++++++++++++---------------------------
 src/compositor.rs |  3 +-
 2 files changed, 38 insertions(+), 52 deletions(-)

diff --git a/src/acceptor.rs b/src/acceptor.rs
index 02401f6a..bc35c93f 100644
--- a/src/acceptor.rs
+++ b/src/acceptor.rs
@@ -1,7 +1,7 @@
 use {
     crate::{
-        client::ClientError,
-        event_loop::{EventLoopDispatcher, EventLoopError, EventLoopId},
+        async_engine::SpawnedFuture,
+        event_loop::EventLoopError,
         state::State,
         utils::{errorfmt::ErrorFmt, oserror::OsError, xrd::xrd},
     },
@@ -26,12 +26,6 @@ pub enum AcceptorError {
     OpenLockFile(#[source] OsError),
     #[error("Could not lock the lock file")]
     LockLockFile(#[source] OsError),
-    #[error("The wayland socket is in an error state")]
-    ErrorEvent,
-    #[error("Could not accept new connections")]
-    AcceptFailed(#[source] OsError),
-    #[error("Could not spawn an event handler for a new connection")]
-    SpawnFailed(#[source] ClientError),
     #[error("Could not bind the socket to an address")]
     BindFailed(#[source] OsError),
     #[error("All wayland addresses in the range 0..1000 are already in use")]
@@ -41,9 +35,7 @@ pub enum AcceptorError {
 }
 
 pub struct Acceptor {
-    ids: [EventLoopId; 2],
     socket: AllocatedSocket,
-    global: Rc<State>,
 }
 
 struct AllocatedSocket {
@@ -148,7 +140,9 @@ fn allocate_socket() -> Result<AllocatedSocket, AcceptorError> {
 }
 
 impl Acceptor {
-    pub fn install(state: &Rc<State>) -> Result<Rc<Acceptor>, AcceptorError> {
+    pub fn install(
+        state: &Rc<State>,
+    ) -> Result<(Rc<Acceptor>, Vec<SpawnedFuture<()>>), AcceptorError> {
         let socket = allocate_socket()?;
         log::info!("bound to socket {}", socket.path.display());
         for fd in [&socket.secure, &socket.insecure] {
@@ -156,24 +150,20 @@ impl Acceptor {
                 return Err(AcceptorError::ListenFailed(e.into()));
             }
         }
-        let id1 = state.el.id();
-        let id2 = state.el.id();
-        let acc = Rc::new(Acceptor {
-            ids: [id1, id2],
-            socket,
-            global: state.clone(),
-        });
-        state.el.insert(
-            id1,
-            Some(acc.socket.insecure.raw()),
-            c::EPOLLIN,
-            acc.clone(),
-        )?;
-        state
-            .el
-            .insert(id2, Some(acc.socket.secure.raw()), c::EPOLLIN, acc.clone())?;
+        let acc = Rc::new(Acceptor { socket });
+        let mut futures = vec![];
+        futures.push(
+            state
+                .eng
+                .spawn(accept(acc.socket.secure.clone(), state.clone(), true)),
+        );
+        futures.push(
+            state
+                .eng
+                .spawn(accept(acc.socket.insecure.clone(), state.clone(), false)),
+        );
         state.acceptor.set(Some(acc.clone()));
-        Ok(acc)
+        Ok((acc, futures))
     }
 
     pub fn socket_name(&self) -> &str {
@@ -186,39 +176,34 @@ impl Acceptor {
     }
 }
 
-impl EventLoopDispatcher for Acceptor {
-    fn dispatch(
-        self: Rc<Self>,
-        fd: Option<i32>,
-        events: i32,
-    ) -> Result<(), Box<dyn std::error::Error>> {
-        if events & (c::EPOLLERR | c::EPOLLHUP) != 0 {
-            return Err(Box::new(AcceptorError::ErrorEvent));
+async fn accept(fd: Rc<OwnedFd>, state: Rc<State>, secure: bool) {
+    loop {
+        if let Err(e) = state.ring.readable(&fd).await {
+            log::error!(
+                "Could not wait for the acceptor to become readable: {}",
+                ErrorFmt(e)
+            );
+            break;
         }
-        let fd = fd.unwrap();
-        let secure = fd == self.socket.secure.raw();
         loop {
             let fd = match uapi::accept4(
-                fd,
+                fd.raw(),
                 uapi::sockaddr_none_mut(),
                 c::SOCK_NONBLOCK | c::SOCK_CLOEXEC,
             ) {
                 Ok((fd, _)) => fd,
                 Err(Errno(c::EAGAIN)) => break,
-                Err(e) => return Err(Box::new(AcceptorError::AcceptFailed(e.into()))),
+                Err(e) => {
+                    log::error!("Could not accept a client: {}", ErrorFmt(OsError::from(e)));
+                    break;
+                }
             };
-            let id = self.global.clients.id();
-            if let Err(e) = self.global.clients.spawn(id, &self.global, fd, secure) {
-                return Err(Box::new(AcceptorError::SpawnFailed(e)));
+            let id = state.clients.id();
+            if let Err(e) = state.clients.spawn(id, &state, fd, secure) {
+                log::error!("Could not spawn a client: {}", ErrorFmt(e));
+                break;
             }
         }
-        Ok(())
-    }
-}
-
-impl Drop for Acceptor {
-    fn drop(&mut self) {
-        let _ = self.global.el.remove(self.ids[0]);
-        let _ = self.global.el.remove(self.ids[1]);
     }
+    state.el.stop();
 }
diff --git a/src/compositor.rs b/src/compositor.rs
index 6975b5da..0f0e6d6e 100644
--- a/src/compositor.rs
+++ b/src/compositor.rs
@@ -190,7 +190,7 @@ fn start_compositor2(
     });
     state.tracker.register(ClientId::from_raw(0));
     create_dummy_output(&state);
-    let acceptor = Acceptor::install(&state)?;
+    let (acceptor, acceptor_future) = Acceptor::install(&state)?;
     forker.install(&state);
     forker.setenv(
         WAYLAND_DISPLAY.as_bytes(),
@@ -202,6 +202,7 @@ fn start_compositor2(
     let compositor = engine.spawn(start_compositor3(state.clone(), test_future));
     el.run()?;
     drop(compositor);
+    drop(acceptor_future);
     drop(acceptor);
     drop(forker);
     engine.clear();