feat: SIGUSR2 handling for toggles (#281)

src-tauri/Cargo.lock

@@ -1425,6 +1425,10 @@ dependencies = [
  "objc2 0.6.3",
  "objc2-app-kit",
  "objc2-foundation 0.3.2",
+ "tempfile",
+ "wayland-client",
+ "wayland-protocols-misc",
+ "wayland-protocols-wlr",
  "windows 0.61.3",
  "x11rb",
  "xkbcommon",
@@ -2296,6 +2300,7 @@ dependencies = [
  "rustfft",
  "serde",
  "serde_json",
+ "signal-hook",
  "strsim",
  "tar",
  "tauri",
@@ -5561,6 +5566,16 @@ version = "1.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0fda2ff0d084019ba4d7c6f371c95d8fd75ce3524c3cb8fb653a3023f6323e64"
 
+[[package]]
+name = "signal-hook"
+version = "0.3.18"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d881a16cf4426aa584979d30bd82cb33429027e42122b169753d6ef1085ed6e2"
+dependencies = [
+ "libc",
+ "signal-hook-registry",
+]
+
 [[package]]
 name = "signal-hook-registry"
 version = "1.4.6"
@@ -7625,6 +7640,19 @@ dependencies = [
  "wayland-scanner",
 ]
 
+[[package]]
+name = "wayland-protocols-misc"
+version = "0.3.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2dfe33d551eb8bffd03ff067a8b44bb963919157841a99957151299a6307d19c"
+dependencies = [
+ "bitflags 2.10.0",
+ "wayland-backend",
+ "wayland-client",
+ "wayland-protocols",
+ "wayland-scanner",
+]
+
 [[package]]
 name = "wayland-protocols-wlr"
 version = "0.3.9"

src-tauri/Cargo.toml

@@ -29,10 +29,10 @@ tauri-build = { version = "2", features = [] }
 [dependencies]
 once_cell = "1"
 tauri = { version = "2.9.1", features = [
-    "protocol-asset",
+  "protocol-asset",
-    "macos-private-api",
+  "macos-private-api",
-    "tray-icon",
+  "tray-icon",
-    'image-png',
+  'image-png',
 ] }
 tauri-plugin-opener = "2.5.2"
 tauri-plugin-store = "2.4.1"
@@ -53,7 +53,7 @@ env_logger = "0.11.6"
 log = "0.4.25"
 tokio = "1.43.0"
 vad-rs = { git = "https://github.com/cjpais/vad-rs", default-features = false }
-enigo = "0.6.1"
+enigo = { version = "0.6.1", features = ["wayland"] }
 rodio = { git = "https://github.com/cjpais/rodio.git" }
 reqwest = { version = "0.11.27", features = ["json", "stream"] }
 futures-util = "0.3"
@@ -73,6 +73,9 @@ tauri-plugin-global-shortcut = "2.3.1"
 tauri-plugin-single-instance = "2.3.2"
 tauri-plugin-updater = "2.9.0"
 
+[target.'cfg(unix)'.dependencies]
+signal-hook = "0.3"
+
 [profile.release]
 lto = true
 codegen-units = 1

src-tauri/src/lib.rs

@@ -7,6 +7,7 @@ mod managers;
 mod overlay;
 mod settings;
 mod shortcut;
+mod signal_handler;
 mod tray;
 mod utils;
 
@@ -23,6 +24,13 @@ use tauri::Emitter;
 use tauri::{AppHandle, Manager};
 use tauri_plugin_autostart::{MacosLauncher, ManagerExt};
 
+#[cfg(unix)]
+use signal_hook::consts::SIGUSR2;
+#[cfg(unix)]
+use signal_hook::iterator::Signals;
+
+use log::info;
+
 #[derive(Default)]
 struct ShortcutToggleStates {
     // Map: shortcut_binding_id -> is_active
@@ -155,6 +163,10 @@ fn trigger_update_check(app: AppHandle) -> Result<(), String> {
 pub fn run() {
     env_logger::init();
 
+    info!("Initializing!");
+    #[cfg(unix)]
+    let signals = Signals::new(&[SIGUSR2]).unwrap();
+
     tauri::Builder::default()
         .plugin(tauri_plugin_single_instance::init(|app, _args, _cwd| {
             show_main_window(app);
@@ -185,6 +197,13 @@ pub fn run() {
             let settings = settings::get_settings(&app.handle());
             let app_handle = app.handle().clone();
 
+            // Set up SIGUSR2 signal handler for toggling transcription
+            //
+            // Note: We register SIGUSR2 here so as to not conflict with
+            // WebKit's default handling of SIGUSR1 for triggering GC cleanup.
+            #[cfg(unix)]
+            signal_handler::setup_signal_handler(app_handle.clone(), signals);
+
             initialize_core_logic(&app_handle);
 
             // Show main window only if not starting hidden

src-tauri/src/signal_handler.rs

@@ -0,0 +1,64 @@
+use crate::actions::ACTION_MAP;
+use crate::ManagedToggleState;
+use log::{debug, info, warn};
+use std::thread;
+use tauri::{AppHandle, Manager};
+
+#[cfg(unix)]
+use signal_hook::consts::SIGUSR2;
+#[cfg(unix)]
+use signal_hook::iterator::Signals;
+
+#[cfg(unix)]
+pub fn setup_signal_handler(app_handle: AppHandle, mut signals: Signals) {
+    let app_handle_for_signal = app_handle.clone();
+
+    info!("SIGUSR2 signal handler registered successfully");
+    thread::spawn(move || {
+        info!("SIGUSR2 signal handler thread started");
+        // This blocks until a signal arrives - much more efficient than polling
+        for sig in signals.forever() {
+            match sig {
+                SIGUSR2 => {
+                    debug!("Received SIGUSR2 signal (signal number: {sig})");
+
+                    let binding_id = "transcribe";
+                    let shortcut_string = "SIGUSR2";
+
+                    if let Some(action) = ACTION_MAP.get(binding_id) {
+                        let toggle_state_manager =
+                            app_handle_for_signal.state::<ManagedToggleState>();
+
+                        let mut states = match toggle_state_manager.lock() {
+                            Ok(s) => s,
+                            Err(e) => {
+                                warn!("Failed to lock toggle state manager: {e}");
+                                continue;
+                            }
+                        };
+
+                        let is_currently_active = states
+                            .active_toggles
+                            .entry(binding_id.to_string())
+                            .or_insert(false);
+
+                        if *is_currently_active {
+                            debug!("SIGUSR2: Stopping transcription (currently active)");
+                            action.stop(&app_handle_for_signal, binding_id, shortcut_string);
+                            *is_currently_active = false; // Update state to inactive
+                            info!("SIGUSR2: Transcription stopped");
+                        } else {
+                            debug!("SIGUSR2: Starting transcription (currently inactive)");
+                            action.start(&app_handle_for_signal, binding_id, shortcut_string);
+                            *is_currently_active = true; // Update state to active
+                            info!("SIGUSR2: Transcription started");
+                        }
+                    } else {
+                        warn!("No action defined in ACTION_MAP for binding ID '{binding_id}'");
+                    }
+                }
+                _ => unreachable!(),
+            }
+        }
+    });
+}