From f2fc1e948079f195feea6d319be600563a935fc1 Mon Sep 17 00:00:00 2001
From: Victoria Brekenfeld <victoria@system76.com>
Date: Tue, 29 Jul 2025 15:57:38 +0200
Subject: [PATCH] dbus: Take lid-inhibitor-locks on systemd systems

---
 Cargo.lock         | 11 +++++++++++
 Cargo.toml         |  3 ++-
 src/dbus/logind.rs | 17 +++++++++++++++++
 src/dbus/mod.rs    |  2 ++
 src/state.rs       | 38 ++++++++++++++++++++++++++++++++++++++
 5 files changed, 70 insertions(+), 1 deletion(-)
 create mode 100644 src/dbus/logind.rs

diff --git a/Cargo.lock b/Cargo.lock
index abfe332b..aa67492a 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -841,6 +841,7 @@ dependencies = [
  "libdisplay-info",
  "libsystemd",
  "log-panics",
+ "logind-zbus",
  "once_cell",
  "ordered-float",
  "parking_lot 0.12.3",
@@ -3060,6 +3061,16 @@ dependencies = [
  "log",
 ]
 
+[[package]]
+name = "logind-zbus"
+version = "5.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "469c962578b549a82f3d0cc72d0f77d1123780fa7121e2b03d78b0780f6ccac6"
+dependencies = [
+ "serde",
+ "zbus",
+]
+
 [[package]]
 name = "loom"
 version = "0.7.2"
diff --git a/Cargo.toml b/Cargo.toml
index da39726f..229b42d6 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -66,6 +66,7 @@ reis = { version = "0.5", features = ["calloop"] }
 # CLI arguments
 clap_lex = "0.7"
 parking_lot = "0.12.3"
+logind-zbus = { version = "5.3.2", optional = true }
 
 [dependencies.id_tree]
 branch = "feature/copy_clone"
@@ -100,7 +101,7 @@ optional = true
 [features]
 debug = ["egui", "egui_plot", "smithay-egui", "anyhow/backtrace"]
 default = ["systemd"]
-systemd = ["libsystemd"]
+systemd = ["libsystemd", "logind-zbus"]
 profile-with-tracy = ["profiling/profile-with-tracy", "tracy-client/default"]
 
 [profile.dev.package.tiny-skia]
diff --git a/src/dbus/logind.rs b/src/dbus/logind.rs
new file mode 100644
index 00000000..75ee9d8d
--- /dev/null
+++ b/src/dbus/logind.rs
@@ -0,0 +1,17 @@
+use std::os::fd::OwnedFd;
+
+use logind_zbus::manager::{InhibitType::HandleLidSwitch, ManagerProxyBlocking};
+use zbus::blocking::Connection;
+
+pub fn inhibit_lid() -> anyhow::Result<OwnedFd> {
+    let conn = Connection::system()?;
+    let proxy = ManagerProxyBlocking::new(&conn)?;
+    let fd = proxy.inhibit(
+        HandleLidSwitch,
+        "cosmic-comp",
+        "External output connected",
+        "block",
+    )?;
+
+    Ok(fd.into())
+}
diff --git a/src/dbus/mod.rs b/src/dbus/mod.rs
index 13b2bcc5..3381eb5a 100644
--- a/src/dbus/mod.rs
+++ b/src/dbus/mod.rs
@@ -4,6 +4,8 @@ use calloop::{InsertError, LoopHandle, RegistrationToken};
 use std::collections::HashMap;
 use zbus::blocking::{fdo::DBusProxy, Connection};
 
+#[cfg(feature = "systemd")]
+pub mod logind;
 mod power;
 
 pub fn init(evlh: &LoopHandle<'static, State>) -> Result<Vec<RegistrationToken>> {
diff --git a/src/state.rs b/src/state.rs
index e20ac349..3f669e66 100644
--- a/src/state.rs
+++ b/src/state.rs
@@ -112,6 +112,9 @@ use smithay::{
 };
 use time::UtcOffset;
 
+#[cfg(feature = "systemd")]
+use std::os::fd::OwnedFd;
+
 use std::{
     cell::RefCell,
     cmp::min,
@@ -249,6 +252,9 @@ pub struct Common {
 
     pub atspi_state: AtspiState,
     pub atspi_ei: crate::wayland::handlers::atspi::AtspiEiState,
+
+    #[cfg(feature = "systemd")]
+    inhibit_lid_fd: Option<OwnedFd>,
 }
 
 #[derive(Debug)]
@@ -504,6 +510,7 @@ impl<'a> LockedBackend<'a> {
         }
 
         loop_handle.insert_idle(move |state| {
+            state.update_inhibitor_locks();
             state.common.update_xwayland_scale();
             state.common.update_xwayland_primary_output();
         });
@@ -707,6 +714,9 @@ impl State {
 
                 atspi_state,
                 atspi_ei: Default::default(),
+
+                #[cfg(feature = "systemd")]
+                inhibit_lid_fd: None,
             },
             backend: BackendData::Unset,
             ready: Once::new(),
@@ -726,6 +736,34 @@ impl State {
             security_context: None,
         }
     }
+
+    fn update_inhibitor_locks(&mut self) {
+        #[cfg(feature = "systemd")]
+        {
+            use tracing::{debug, error};
+
+            let outputs = self.backend.lock().all_outputs();
+            let should_handle_lid = outputs.iter().any(|o| o.is_internal()) && outputs.len() >= 2;
+
+            if should_handle_lid {
+                if self.common.inhibit_lid_fd.is_none() {
+                    match crate::dbus::logind::inhibit_lid() {
+                        Ok(fd) => {
+                            debug!("Inhibiting lid switch");
+                            self.common.inhibit_lid_fd = Some(fd);
+                        }
+                        Err(err) => {
+                            error!("Failed to inhibit lid switch: {}", err);
+                        }
+                    }
+                }
+            } else {
+                if self.common.inhibit_lid_fd.take().is_some() {
+                    debug!("Removing inhibitor-lock on lid switch")
+                }
+            }
+        }
+    }
 }
 
 fn primary_scanout_output_compare<'a>(