Configurable capture backend (#150)

capture backend can now be configured via the `capture_backend` cli argument / config entry

src/capture/error.rs

@@ -0,0 +1,140 @@
+use std::fmt::Display;
+use thiserror::Error;
+
+#[cfg(all(unix, feature = "wayland", not(target_os = "macos")))]
+use std::io;
+#[cfg(all(unix, feature = "wayland", not(target_os = "macos")))]
+use wayland_client::{
+    backend::WaylandError,
+    globals::{BindError, GlobalError},
+    ConnectError, DispatchError,
+};
+
+#[derive(Debug, Error)]
+pub enum CaptureCreationError {
+    #[cfg(all(unix, feature = "libei", not(target_os = "macos")))]
+    Libei(#[from] LibeiCaptureCreationError),
+    #[cfg(all(unix, feature = "wayland", not(target_os = "macos")))]
+    LayerShell(#[from] LayerShellCaptureCreationError),
+    #[cfg(all(unix, feature = "x11", not(target_os = "macos")))]
+    X11(#[from] X11InputCaptureCreationError),
+    #[cfg(target_os = "macos")]
+    Macos(#[from] MacOSInputCaptureCreationError),
+    #[cfg(windows)]
+    Windows,
+}
+
+impl Display for CaptureCreationError {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        let reason = match self {
+            #[cfg(all(unix, feature = "libei", not(target_os = "macos")))]
+            CaptureCreationError::Libei(reason) => {
+                format!("error creating portal backend: {reason}")
+            }
+            #[cfg(all(unix, feature = "wayland", not(target_os = "macos")))]
+            CaptureCreationError::LayerShell(reason) => {
+                format!("error creating layer-shell backend: {reason}")
+            }
+            #[cfg(all(unix, feature = "x11", not(target_os = "macos")))]
+            CaptureCreationError::X11(e) => format!("{e}"),
+            #[cfg(target_os = "macos")]
+            CaptureCreationError::Macos(e) => format!("{e}"),
+            #[cfg(windows)]
+            CaptureCreationError::Windows => String::from(""),
+        };
+        write!(f, "could not create input capture: {reason}")
+    }
+}
+
+#[cfg(all(unix, feature = "libei", not(target_os = "macos")))]
+#[derive(Debug, Error)]
+pub enum LibeiCaptureCreationError {
+    Ashpd(#[from] ashpd::Error),
+}
+
+#[cfg(all(unix, feature = "libei", not(target_os = "macos")))]
+impl Display for LibeiCaptureCreationError {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            LibeiCaptureCreationError::Ashpd(portal_error) => write!(f, "{portal_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")))]
+#[derive(Debug, Error)]
+pub enum LayerShellCaptureCreationError {
+    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")))]
+impl Display for LayerShellCaptureCreationError {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            LayerShellCaptureCreationError::Bind(e) => write!(f, "{e}"),
+            LayerShellCaptureCreationError::Connect(e) => {
+                write!(f, "could not connect to wayland compositor: {e}")
+            }
+            LayerShellCaptureCreationError::Global(e) => write!(f, "wayland error: {e}"),
+            LayerShellCaptureCreationError::Wayland(e) => write!(f, "wayland error: {e}"),
+            LayerShellCaptureCreationError::Dispatch(e) => {
+                write!(f, "error dispatching wayland events: {e}")
+            }
+            LayerShellCaptureCreationError::Io(e) => write!(f, "io error: {e}"),
+        }
+    }
+}
+
+#[cfg(all(unix, feature = "x11", not(target_os = "macos")))]
+#[derive(Debug, Error)]
+pub enum X11InputCaptureCreationError {
+    NotImplemented,
+}
+
+#[cfg(all(unix, feature = "x11", not(target_os = "macos")))]
+impl Display for X11InputCaptureCreationError {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        write!(f, "X11 input capture is not yet implemented :(")
+    }
+}
+#[cfg(target_os = "macos")]
+#[derive(Debug, Error)]
+pub enum MacOSInputCaptureCreationError {
+    NotImplemented,
+}
+
+#[cfg(target_os = "macos")]
+impl Display for MacOSInputCaptureCreationError {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        write!(f, "macos input capture is not yet implemented :(")
+    }
+}

src/capture/libei.rs

@@ -36,6 +36,8 @@ use crate::{
     event::{Event, KeyboardEvent, PointerEvent},
 };
 
+use super::error::LibeiCaptureCreationError;
+
 #[derive(Debug)]
 enum ProducerEvent {
     Release,
@@ -131,7 +133,7 @@ impl<'a> Drop for LibeiInputCapture<'a> {
 
 async fn create_session<'a>(
     input_capture: &'a InputCapture<'a>,
-) -> Result<(Session<'a>, BitFlags<Capabilities>)> {
+) -> std::result::Result<(Session<'a>, BitFlags<Capabilities>), ashpd::Error> {
     log::debug!("creating input capture session");
     let (session, capabilities) = loop {
         match input_capture
@@ -213,7 +215,7 @@ async fn wait_for_active_client(
 }
 
 impl<'a> LibeiInputCapture<'a> {
-    pub async fn new() -> Result<Self> {
+    pub async fn new() -> std::result::Result<Self, LibeiCaptureCreationError> {
         let input_capture = Box::pin(InputCapture::new().await?);
         let input_capture_ptr = input_capture.as_ref().get_ref() as *const InputCapture<'static>;
         let mut first_session = Some(create_session(unsafe { &*input_capture_ptr }).await?);

src/capture/macos.rs

@@ -1,7 +1,7 @@
+use crate::capture::error::MacOSInputCaptureCreationError;
 use crate::capture::InputCapture;
 use crate::client::{ClientEvent, ClientHandle};
 use crate::event::Event;
-use anyhow::{anyhow, Result};
 use futures_core::Stream;
 use std::task::{Context, Poll};
 use std::{io, pin::Pin};
@@ -9,8 +9,8 @@ use std::{io, pin::Pin};
 pub struct MacOSInputCapture;
 
 impl MacOSInputCapture {
-    pub fn new() -> Result<Self> {
-        Err(anyhow!("not yet implemented"))
+    pub fn new() -> std::result::Result<Self, MacOSInputCaptureCreationError> {
+        Err(MacOSInputCaptureCreationError::NotImplemented)
     }
 }
 

src/capture/wayland.rs

@@ -1,9 +1,8 @@
 use crate::{
-    capture::InputCapture,
+    capture::{error::WaylandBindError, InputCapture},
     client::{ClientEvent, ClientHandle, Position},
 };
 
-use anyhow::{anyhow, Result};
 use futures_core::Stream;
 use memmap::MmapOptions;
 use std::{
@@ -68,6 +67,8 @@ use tempfile;
 
 use crate::event::{Event, KeyboardEvent, PointerEvent};
 
+use super::error::LayerShellCaptureCreationError;
+
 struct Globals {
     compositor: wl_compositor::WlCompositor,
     pointer_constraints: ZwpPointerConstraintsV1,
@@ -258,64 +259,37 @@ fn draw(f: &mut File, (width, height): (u32, u32)) {
 }
 
 impl WaylandInputCapture {
-    pub fn new() -> Result<Self> {
-        let conn = match Connection::connect_to_env() {
-            Ok(c) => c,
-            Err(e) => return Err(anyhow!("could not connect to wayland compositor: {e:?}")),
-        };
-
-        let (g, mut queue) = match registry_queue_init::<State>(&conn) {
-            Ok(q) => q,
-            Err(e) => return Err(anyhow!("failed to initialize wl_registry: {e:?}")),
-        };
+    pub fn new() -> std::result::Result<Self, LayerShellCaptureCreationError> {
+        let conn = Connection::connect_to_env()?;
+        let (g, mut queue) = registry_queue_init::<State>(&conn)?;
 
         let qh = queue.handle();
 
-        let compositor: wl_compositor::WlCompositor = match g.bind(&qh, 4..=5, ()) {
-            Ok(compositor) => compositor,
-            Err(_) => return Err(anyhow!("wl_compositor >= v4 not supported")),
-        };
-
-        let xdg_output_manager: ZxdgOutputManagerV1 = match g.bind(&qh, 1..=3, ()) {
-            Ok(xdg_output_manager) => xdg_output_manager,
-            Err(_) => return Err(anyhow!("xdg_output not supported!")),
-        };
-
-        let shm: wl_shm::WlShm = match g.bind(&qh, 1..=1, ()) {
-            Ok(wl_shm) => wl_shm,
-            Err(_) => return Err(anyhow!("wl_shm v1 not supported")),
-        };
-
-        let layer_shell: ZwlrLayerShellV1 = match g.bind(&qh, 3..=4, ()) {
-            Ok(layer_shell) => layer_shell,
-            Err(_) => return Err(anyhow!("zwlr_layer_shell_v1 >= v3 not supported - required to display a surface at the edge of the screen")),
-        };
-
-        let seat: wl_seat::WlSeat = match g.bind(&qh, 7..=8, ()) {
-            Ok(wl_seat) => wl_seat,
-            Err(_) => return Err(anyhow!("wl_seat >= v7 not supported")),
-        };
-
-        let pointer_constraints: ZwpPointerConstraintsV1 = match g.bind(&qh, 1..=1, ()) {
-            Ok(pointer_constraints) => pointer_constraints,
-            Err(_) => return Err(anyhow!("zwp_pointer_constraints_v1 not supported")),
-        };
-
-        let relative_pointer_manager: ZwpRelativePointerManagerV1 = match g.bind(&qh, 1..=1, ()) {
-            Ok(relative_pointer_manager) => relative_pointer_manager,
-            Err(_) => return Err(anyhow!("zwp_relative_pointer_manager_v1 not supported")),
-        };
-
-        let shortcut_inhibit_manager: ZwpKeyboardShortcutsInhibitManagerV1 =
-            match g.bind(&qh, 1..=1, ()) {
-                Ok(shortcut_inhibit_manager) => shortcut_inhibit_manager,
-                Err(_) => {
-                    return Err(anyhow!(
-                        "zwp_keyboard_shortcuts_inhibit_manager_v1 not supported"
-                    ))
-                }
-            };
+        let compositor: wl_compositor::WlCompositor = g
+            .bind(&qh, 4..=5, ())
+            .map_err(|e| WaylandBindError::new(e, "wl_compositor 4..=5"))?;
+        let xdg_output_manager: ZxdgOutputManagerV1 = g
+            .bind(&qh, 1..=3, ())
+            .map_err(|e| WaylandBindError::new(e, "xdg_output_manager 1..=3"))?;
+        let shm: wl_shm::WlShm = g
+            .bind(&qh, 1..=1, ())
+            .map_err(|e| WaylandBindError::new(e, "wl_shm"))?;
+        let layer_shell: ZwlrLayerShellV1 = g
+            .bind(&qh, 3..=4, ())
+            .map_err(|e| WaylandBindError::new(e, "wlr_layer_shell 3..=4"))?;
+        let seat: wl_seat::WlSeat = g
+            .bind(&qh, 7..=8, ())
+            .map_err(|e| WaylandBindError::new(e, "wl_seat 7..=8"))?;
 
+        let pointer_constraints: ZwpPointerConstraintsV1 = g
+            .bind(&qh, 1..=1, ())
+            .map_err(|e| WaylandBindError::new(e, "zwp_pointer_constraints_v1"))?;
+        let relative_pointer_manager: ZwpRelativePointerManagerV1 = g
+            .bind(&qh, 1..=1, ())
+            .map_err(|e| WaylandBindError::new(e, "zwp_relative_pointer_manager_v1"))?;
+        let shortcut_inhibit_manager: ZwpKeyboardShortcutsInhibitManagerV1 = g
+            .bind(&qh, 1..=1, ())
+            .map_err(|e| WaylandBindError::new(e, "zwp_keyboard_shortcuts_inhibit_manager_v1"))?;
         let outputs = vec![];
 
         let g = Globals {

src/capture/windows.rs

@@ -575,7 +575,7 @@ fn update_clients(client_event: ClientEvent) {
 }
 
 impl WindowsInputCapture {
-    pub(crate) fn new() -> Result<Self> {
+    pub(crate) fn new() -> Self {
         unsafe {
             let (tx, rx) = channel(10);
             EVENT_TX.replace(tx);
@@ -583,10 +583,10 @@ impl WindowsInputCapture {
             let msg_thread = Some(thread::spawn(|| message_thread(ready_tx)));
             /* wait for thread to set its id */
             ready_rx.recv().expect("channel closed");
-            Ok(Self {
+            Self {
                 msg_thread,
                 event_rx: rx,
-            })
+            }
         }
     }
 }

src/capture/x11.rs

@@ -1,4 +1,3 @@
-use anyhow::{anyhow, Result};
 use std::io;
 use std::task::Poll;
 
@@ -9,11 +8,13 @@ use crate::event::Event;
 
 use crate::client::{ClientEvent, ClientHandle};
 
+use super::error::X11InputCaptureCreationError;
+
 pub struct X11InputCapture {}
 
 impl X11InputCapture {
-    pub fn new() -> Result<Self> {
-        Err(anyhow!("not implemented"))
+    pub fn new() -> std::result::Result<Self, X11InputCaptureCreationError> {
+        Err(X11InputCaptureCreationError::NotImplemented)
     }
 }