update

src/emulate.rs

@@ -2,11 +2,12 @@ use async_trait::async_trait;
 use std::future;
 
 use crate::{
-    client::{ClientEvent, ClientHandle},
+    client::{ClientEvent, ClientHandle}, config::EmulationBackend, event::Event
-    event::Event,
 };
 use anyhow::Result;
 
+use self::error::EmulationCreationError;
+
 #[cfg(windows)]
 pub mod windows;
 
@@ -42,10 +43,10 @@ pub trait InputEmulation: Send {
     async fn destroy(&mut self);
 }
 
-pub async fn create(backend: Option<EmulationBackend>) -> Box<dyn InputEmulation> {
+pub async fn create(backend: Option<EmulationBackend>) -> Result<Box<dyn InputEmulation>, EmulationCreationError> {
     #[cfg(windows)]
     match windows::WindowsEmulation::new() {
-        Ok(c) => return Box::new(c),
+        Ok(c) => return Ok(Box::new(c)),
         Err(e) => log::warn!("windows input emulation unavailable: {e}"),
     }
 
@@ -53,7 +54,7 @@ pub async fn create(backend: Option<EmulationBackend>) -> Box<dyn InputEmulation
     match macos::MacOSEmulation::new() {
         Ok(c) => {
             log::info!("using macos input emulation");
-            return Box::new(c);
+            return Ok(Box::new(c));
         }
         Err(e) => log::error!("macos input emulatino not available: {e}"),
     }
@@ -62,7 +63,7 @@ pub async fn create(backend: Option<EmulationBackend>) -> Box<dyn InputEmulation
     match wlroots::WlrootsEmulation::new() {
         Ok(c) => {
             log::info!("using wlroots input emulation");
-            return Box::new(c);
+            return Ok(Box::new(c));
         }
         Err(e) => log::info!("wayland backend not available: {e}"),
     }
@@ -71,7 +72,7 @@ pub async fn create(backend: Option<EmulationBackend>) -> Box<dyn InputEmulation
     match libei::LibeiEmulation::new().await {
         Ok(c) => {
             log::info!("using libei input emulation");
-            return Box::new(c);
+            return Ok(Box::new(c));
         }
         Err(e) => log::info!("libei not available: {e}"),
     }
@@ -80,7 +81,7 @@ pub async fn create(backend: Option<EmulationBackend>) -> Box<dyn InputEmulation
     match xdg_desktop_portal::DesktopPortalEmulation::new().await {
         Ok(c) => {
             log::info!("using xdg-remote-desktop-portal input emulation");
-            return Box::new(c);
+            return Ok(Box::new(c));
         }
         Err(e) => log::info!("remote desktop portal not available: {e}"),
     }
@@ -89,11 +90,11 @@ pub async fn create(backend: Option<EmulationBackend>) -> Box<dyn InputEmulation
     match x11::X11Emulation::new() {
         Ok(c) => {
             log::info!("using x11 input emulation");
-            return Box::new(c);
+            return Ok(Box::new(c));
         }
         Err(e) => log::info!("x11 input emulation not available: {e}"),
     }
 
     log::error!("falling back to dummy input emulation");
-    Box::new(dummy::DummyEmulation::new())
+    Ok(Box::new(dummy::DummyEmulation::new()))
 }

src/emulate/error.rs

@@ -0,0 +1,98 @@
+use std::{fmt::Display, io};
+
+use thiserror::Error;
+use wayland_client::{backend::WaylandError, globals::{BindError, GlobalError}, ConnectError, DispatchError};
+
+
+#[derive(Debug, Error)]
+pub enum EmulationCreationError {
+    #[cfg(all(unix, feature = "wayland", not(target_os = "macos")))]
+    Wlroots(#[from] WlrootsEmulationCreationError),
+    #[cfg(all(unix, feature = "libei", not(target_os = "macos")))]
+    Libei(#[from] LibeiEmulationCreationError),
+    #[cfg(all(unix, feature = "xdg_desktop_portal", not(target_os = "macos")))]
+    Xdp(#[from] XdpEmulationCreationError),
+    #[cfg(all(unix, feature = "x11", not(target_os = "macos")))]
+    X11(#[from] X11EmulationCreationError),
+}
+
+impl Display for EmulationCreationError {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        let reason = match self {
+            EmulationCreationError::Wlroots(e) => format!("wlroots backend: {e}"),
+            EmulationCreationError::Libei(e) => todo!("libei backend: {e}"),
+            EmulationCreationError::Xdp(e) => todo!("desktop portal backend: {e}"),
+            EmulationCreationError::X11(e) => todo!("x11 backend: {e}"),
+        };
+        write!(f, "could not create input emulation backend: {reason}")
+    }
+}
+
+#[cfg(all(unix, feature = "wayland", not(target_os = "macos")))]
+#[derive(Debug, Error)]
+pub enum WlrootsEmulationCreationError {
+    Connect(#[from] ConnectError),
+    Global(#[from] GlobalError),
+    Wayland(#[from] WaylandError),
+    Bind(#[from] WaylandBindError),
+    Dispatch(#[from] DispatchError),
+    Io(#[from] io::Error),
+}
+
+#[cfg(all(unix, feature = "wayland", not(target_os = "macos")))]
+#[derive(Debug, Error)]
+pub struct WaylandBindError {
+    inner: BindError,
+    protocol: &'static str,
+}
+#[cfg(all(unix, feature = "wayland", not(target_os = "macos")))]
+impl WaylandBindError {
+    pub(crate) fn new(inner: BindError, protocol: &'static str) -> Self {
+        Self { inner, protocol }
+    }
+}
+
+
+#[cfg(all(unix, feature = "wayland", not(target_os = "macos")))]
+impl Display for WaylandBindError {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        write!(
+            f,
+            "{} protocol not supported: {}",
+            self.protocol, self.inner
+        )
+    }
+}
+
+#[cfg(all(unix, feature = "wayland", not(target_os = "macos")))]
+impl Display for WlrootsEmulationCreationError {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            WlrootsEmulationCreationError::Bind(e) => write!(f, "{e}"),
+            WlrootsEmulationCreationError::Connect(e) => {
+                write!(f, "could not connect to wayland compositor: {e}")
+            }
+            WlrootsEmulationCreationError::Global(e) => write!(f, "wayland error: {e}"),
+            WlrootsEmulationCreationError::Wayland(e) => write!(f, "wayland error: {e}"),
+            WlrootsEmulationCreationError::Dispatch(e) => {
+                write!(f, "error dispatching wayland events: {e}")
+            }
+            WlrootsEmulationCreationError::Io(e) => write!(f, "io error: {e}"),
+        }
+    }
+}
+
+#[cfg(all(unix, feature = "libei", not(target_os = "macos")))]
+#[derive(Debug, Error)]
+pub enum LibeiEmulationCreationError {}
+
+
+#[cfg(all(unix, feature = "xdg_desktop_portal", not(target_os = "macos")))]
+#[derive(Debug, Error)]
+pub enum XdpEmulationCreationError {}
+
+
+
+#[cfg(all(unix, feature = "x11", not(target_os = "macos")))]
+#[derive(Debug, Error)]
+pub enum X11EmulationCreationError {}

src/emulate/libei.rs

@@ -1,3 +1,4 @@
+use anyhow::{anyhow, Result};
 use std::{
     collections::HashMap,
     os::{fd::OwnedFd, unix::net::UnixStream},

src/emulation_test.rs

@@ -1,4 +1,5 @@
 use crate::client::{ClientEvent, Position};
+use crate::config::Config;
 use crate::emulate;
 use crate::event::{Event, PointerEvent};
 use anyhow::Result;
@@ -13,14 +14,16 @@ pub fn run() -> Result<()> {
         .enable_time()
         .build()?;
 
-    runtime.block_on(LocalSet::new().run_until(input_emulation_test()))
+    let config = Config::new()?;
+
+    runtime.block_on(LocalSet::new().run_until(input_emulation_test(config)))
 }
 
 const FREQUENCY_HZ: f64 = 1.0;
 const RADIUS: f64 = 100.0;
 
-async fn input_emulation_test() -> Result<()> {
+async fn input_emulation_test(config: Config) -> Result<()> {
-    let mut emulation = emulate::create().await;
+    let mut emulation = emulate::create(config.emulation_backend).await?;
     emulation
         .notify(ClientEvent::Create(0, Position::Left))
         .await;

src/server/emulation_task.rs

@@ -72,7 +72,7 @@ pub fn new(
         emulate.destroy().await;
         anyhow::Ok(())
     });
-    (emulate_task, tx)
+    Ok((emulate_task, tx))
 }
 
 async fn handle_udp_rx(