diff options
| -rw-r--r-- | crates/wayland/src/udev/platform.rs | 4 | ||||
| -rw-r--r-- | crates/wayland/src/udev/session.rs | 55 |
2 files changed, 54 insertions, 5 deletions
diff --git a/crates/wayland/src/udev/platform.rs b/crates/wayland/src/udev/platform.rs index cbcee64..1d2ef0e 100644 --- a/crates/wayland/src/udev/platform.rs +++ b/crates/wayland/src/udev/platform.rs @@ -269,8 +269,8 @@ impl UdevPlatform { let handle = event_loop.handle(); register_drm_fd(&handle, &card)?; - register_libinput(&handle, &session, &seat_name)?; - register_session_notifier(&handle, notifier)?; + let libinput_handle = register_libinput(&handle, &session, &seat_name)?; + register_session_notifier(&handle, notifier, libinput_handle)?; if let Err(e) = register_udev_monitor(&handle, &seat_name) { log::warn!("udev: connector hotplug unavailable ({e}); monitors are fixed at startup"); } diff --git a/crates/wayland/src/udev/session.rs b/crates/wayland/src/udev/session.rs index a6b7349..196740b 100644 --- a/crates/wayland/src/udev/session.rs +++ b/crates/wayland/src/udev/session.rs @@ -38,9 +38,20 @@ pub(crate) fn register_drm_fd(handle: &LoopHandle<'static, CompState>, card: &Rc Ok(()) } -pub(crate) fn register_libinput(handle: &LoopHandle<'static, CompState>, session: &LibSeatSession, seat_name: &str) -> PlatformResult<()> { +/// Registers the real libinput event source and hands back a second, +/// reference-counted handle onto the exact same underlying context (`Libinput` +/// wraps a `libinput_ref`/`libinput_unref`-counted C pointer - see its own +/// `Clone` impl - so this is the same live context `LibinputInputBackend` +/// dispatches events from, not a separate one) for `register_session_notifier` +/// to call `suspend()`/`resume()` on across a VT switch. `LibinputInputBackend` +/// itself only ever exposes an immutable `&Libinput` (`context()`), and is +/// moved into calloop's event source registration below with no way to get +/// a `&mut` back out afterward - cloning before that move is the only way +/// to keep a callable handle at all. +pub(crate) fn register_libinput(handle: &LoopHandle<'static, CompState>, session: &LibSeatSession, seat_name: &str) -> PlatformResult<Libinput> { let mut libinput_context = Libinput::new_with_udev::<LibinputSessionInterface<LibSeatSession>>(session.clone().into()); libinput_context.udev_assign_seat(seat_name).map_err(|_| PlatformError::Other("udev: libinput udev_assign_seat failed".into()))?; + let resume_handle = libinput_context.clone(); let libinput_backend = LibinputInputBackend::new(libinput_context); handle @@ -48,10 +59,16 @@ pub(crate) fn register_libinput(handle: &LoopHandle<'static, CompState>, session handle_libinput_event(data, event); }) .map_err(|e| PlatformError::Other(format!("failed to register libinput backend: {e}")))?; - Ok(()) + Ok(resume_handle) } -pub(crate) fn register_session_notifier(handle: &LoopHandle<'static, CompState>, notifier: LibSeatSessionNotifier) -> PlatformResult<()> { +/// `libinput` is a second handle onto the exact same context +/// `register_libinput` gave its own event source - see that function's own +/// doc comment for why a clone is the only way to get one at all. Kept +/// alive by this closure for as long as this event source is registered +/// (the entire life of the process), purely so `suspend()`/`resume()` can be +/// called on it here. +pub(crate) fn register_session_notifier(handle: &LoopHandle<'static, CompState>, notifier: LibSeatSessionNotifier, mut libinput: Libinput) -> PlatformResult<()> { handle .insert_source(notifier, move |event, &mut (), data: &mut CompState| { let Some(udev) = data.udev.as_mut() else { return }; @@ -59,10 +76,42 @@ pub(crate) fn register_session_notifier(handle: &LoopHandle<'static, CompState>, SessionEvent::PauseSession => { log::info!("udev: session paused (VT switch away)"); udev.active = false; + // Not strictly required (the kernel revokes every input + // device's fd across a VT switch regardless), but this + // is the documented, correct way to tell libinput that's + // about to happen rather than let it discover revoked + // fds as surprise read errors - see `resume()`'s own + // doc comment below for why the other half of this pair + // is not optional at all. + libinput.suspend(); } SessionEvent::ActivateSession => { log::info!("udev: session resumed (VT switch back)"); udev.active = true; + // Without this, libinput's own internal device list + // stays exactly as it was before the switch away, still + // holding the same file descriptors the kernel already + // revoked the moment this session lost the VT -- + // `receive_events`/`dispatch` on a revoked fd doesn't + // error, it just silently never produces another event, + // forever. Confirmed live: after one real VT switch, no + // further keyboard or mouse input reached this + // compositor for the rest of the session (30+ minutes, + // multiple confirmed attempts) with literally nothing + // logged anywhere to explain it - rendering, the DRM/ + // DPMS state above, and even libseat's own session + // activation all recovered correctly on their own, which + // is what made this the one piece actually missing + // rather than a repeat of the DPMS bug. `resume()` + // (`libinput_resume`) is libinput's own documented API + // for exactly this: it re-opens every device through + // the (now reactivated) session and resumes producing + // real events, the same call every other libinput-based + // compositor's session-resume path makes and this one + // never did. + if libinput.resume().is_err() { + log::warn!("udev: libinput resume failed after VT switch back - input devices may not recover; a full restart will be needed if so"); + } let card = udev.card.clone(); // A flip issued right before the VT switch away may |