feat: add x11 feature flag to allow disabling x11 dependencies (#1103)

Author: aurelj

.changes/x11-feature.md

@@ -0,0 +1,5 @@
+---
+tao: minor
+---
+
+Added `x11` feature flag (enabled by default).

Cargo.toml

@@ -16,7 +16,7 @@ documentation = "https://docs.rs/tao"
 categories = [ "gui" ]
 
 [package.metadata.docs.rs]
-features = [ "rwh_04", "rwh_05", "rwh_06", "serde" ]
+features = [ "rwh_04", "rwh_05", "rwh_06", "serde", "x11" ]
 default-target = "x86_64-unknown-linux-gnu"
 targets = [
   "i686-pc-windows-msvc",
@@ -27,11 +27,12 @@ targets = [
 ]
 
 [features]
-default = [ "rwh_06" ]
+default = [ "rwh_06", "x11" ]
 serde = [ "dep:serde", "dpi/serde" ]
 rwh_04 = [ "dep:rwh_04" ]
 rwh_05 = [ "dep:rwh_05" ]
 rwh_06 = [ "dep:rwh_06" ]
+x11 = [ "dep:gdkx11-sys", "dep:x11-dl" ]
 
 [workspace]
 members = [ "tao-macros" ]
@@ -147,8 +148,8 @@ scopeguard = "1.2"
 
 [target."cfg(any(target_os = \"linux\", target_os = \"dragonfly\", target_os = \"freebsd\", target_os = \"openbsd\", target_os = \"netbsd\"))".dependencies]
 gtk = "0.18"
-gdkx11-sys = "0.18"
+gdkx11-sys = { version = "0.18", optional = true }
 gdkwayland-sys = "0.18.0"
-x11-dl = "2.21"
+x11-dl = { version = "2.21", optional = true }
 parking_lot = "0.12"
 dlopen2 = "0.7.0"

src/platform/unix.rs

@@ -10,21 +10,26 @@
   target_os = "openbsd"
 ))]
 
+#[cfg(feature = "x11")]
 use std::{os::raw::c_int, sync::Arc};
 
 // XConnection utilities
 #[doc(hidden)]
+#[cfg(feature = "x11")]
 pub use crate::platform_impl::x11;
 
+#[cfg(feature = "x11")]
+use crate::platform_impl::x11::xdisplay::XError;
 pub use crate::platform_impl::EventLoop as UnixEventLoop;
 use crate::{
   error::{ExternalError, OsError},
   event_loop::{EventLoopBuilder, EventLoopWindowTarget},
   monitor::MonitorHandle,
-  platform_impl::{x11::xdisplay::XError, Parent, Window as UnixWindow},
+  platform_impl::{Parent, Window as UnixWindow},
   window::{Window, WindowBuilder},
 };
 
+#[cfg(feature = "x11")]
 use self::x11::xdisplay::XConnection;
 
 /// Additional methods on `EventLoop` that are specific to Unix.
@@ -201,8 +206,10 @@ pub trait EventLoopWindowTargetExtUnix {
   fn is_wayland(&self) -> bool;
 
   /// True if the `EventLoopWindowTarget` uses X11.
+  #[cfg(feature = "x11")]
   fn is_x11(&self) -> bool;
 
+  #[cfg(feature = "x11")]
   fn xlib_xconnection(&self) -> Option<Arc<XConnection>>;
 
   // /// Returns a pointer to the `wl_display` object of wayland that is used by this
@@ -226,11 +233,13 @@ impl<T> EventLoopWindowTargetExtUnix for EventLoopWindowTarget<T> {
     self.p.is_wayland()
   }
 
+  #[cfg(feature = "x11")]
   #[inline]
   fn is_x11(&self) -> bool {
     !self.p.is_wayland()
   }
 
+  #[cfg(feature = "x11")]
   #[inline]
   fn xlib_xconnection(&self) -> Option<Arc<XConnection>> {
     if self.is_x11() {
@@ -266,6 +275,7 @@ impl<T> EventLoopWindowTargetExtUnix for EventLoopWindowTarget<T> {
   }
 }
 
+#[cfg(feature = "x11")]
 unsafe extern "C" fn x_error_callback(
   _display: *mut x11::ffi::Display,
   event: *mut x11::ffi::XErrorEvent,

src/platform_impl/linux/event_loop.rs

@@ -24,6 +24,8 @@ use gtk::{
   Settings,
 };
 
+#[cfg(feature = "x11")]
+use crate::platform_impl::platform::device;
 use crate::{
   dpi::{LogicalPosition, LogicalSize, PhysicalPosition},
   error::ExternalError,
@@ -33,7 +35,7 @@ use crate::{
   event_loop::{ControlFlow, EventLoopClosed, EventLoopWindowTarget as RootELW},
   keyboard::ModifiersState,
   monitor::MonitorHandle as RootMonitorHandle,
-  platform_impl::platform::{device, DEVICE_ID},
+  platform_impl::platform::DEVICE_ID,
   window::{
     CursorIcon, Fullscreen, ProgressBarState, ResizeDirection, Theme, WindowId as RootWindowId,
   },
@@ -123,6 +125,7 @@ impl<T> EventLoopWindowTarget<T> {
       let display_handle = rwh_06::WaylandDisplayHandle::new(display);
       Ok(rwh_06::RawDisplayHandle::Wayland(display_handle))
     } else {
+      #[cfg(feature = "x11")]
       unsafe {
         if let Ok(xlib) = x11_dl::xlib::Xlib::open() {
           let display = (xlib.XOpenDisplay)(std::ptr::null());
@@ -134,13 +137,16 @@ impl<T> EventLoopWindowTarget<T> {
           Err(rwh_06::HandleError::Unavailable)
         }
       }
+      #[cfg(not(feature = "x11"))]
+      Err(rwh_06::HandleError::Unavailable)
     }
   }
 
   pub fn is_wayland(&self) -> bool {
     self.display.backend().is_wayland()
   }
 
+  #[cfg(feature = "x11")]
   pub fn is_x11(&self) -> bool {
     self.display.backend().is_x11()
   }
@@ -249,6 +255,7 @@ impl<T: 'static> EventLoop<T> {
     };
 
     // Spawn x11 thread to receive Device events.
+    #[cfg(feature = "x11")]
     let run_device_thread = if window_target.is_x11() {
       let (device_tx, device_rx) = glib::MainContext::channel(glib::Priority::default());
       let user_event_tx = user_event_tx.clone();
@@ -272,6 +279,8 @@ impl<T: 'static> EventLoop<T> {
     } else {
       None
     };
+    #[cfg(not(feature = "x11"))]
+    let run_device_thread = None;
 
     let mut taskbar = TaskbarIndicator::new();
     let is_wayland = window_target.is_wayland();

src/platform_impl/linux/mod.rs

@@ -2,6 +2,7 @@
 // Copyright 2021-2023 Tauri Programme within The Commons Conservancy
 // SPDX-License-Identifier: Apache-2.0
 
+#[cfg(feature = "x11")]
 mod device;
 mod event_loop;
 mod icon;
@@ -13,6 +14,7 @@ mod window;
 
 pub mod taskbar;
 pub mod wayland;
+#[cfg(feature = "x11")]
 pub mod x11;
 
 pub use self::keycode::{keycode_from_scancode, keycode_to_scancode};

src/platform_impl/linux/window.rs

@@ -952,9 +952,14 @@ impl Window {
         let window_handle = rwh_06::WaylandWindowHandle::new(surface);
         Ok(rwh_06::RawWindowHandle::Wayland(window_handle))
       } else {
-        let xid = unsafe { gdk_x11_sys::gdk_x11_window_get_xid(window.as_ptr() as *mut _) };
-        let window_handle = rwh_06::XlibWindowHandle::new(xid);
-        Ok(rwh_06::RawWindowHandle::Xlib(window_handle))
+        #[cfg(feature = "x11")]
+        {
+          let xid = unsafe { gdk_x11_sys::gdk_x11_window_get_xid(window.as_ptr() as *mut _) };
+          let window_handle = rwh_06::XlibWindowHandle::new(xid);
+          Ok(rwh_06::RawWindowHandle::Xlib(window_handle))
+        }
+        #[cfg(not(feature = "x11"))]
+        Err(rwh_06::HandleError::Unavailable)
       }
     } else {
       Err(rwh_06::HandleError::Unavailable)
@@ -972,6 +977,7 @@ impl Window {
       let display_handle = rwh_06::WaylandDisplayHandle::new(display);
       Ok(rwh_06::RawDisplayHandle::Wayland(display_handle))
     } else {
+      #[cfg(feature = "x11")]
       if let Ok(xlib) = x11_dl::xlib::Xlib::open() {
         unsafe {
           let display = (xlib.XOpenDisplay)(std::ptr::null());
@@ -983,6 +989,8 @@ impl Window {
       } else {
         Err(rwh_06::HandleError::Unavailable)
       }
+      #[cfg(not(feature = "x11"))]
+      Err(rwh_06::HandleError::Unavailable)
     }
   }