Implement mark

README.md

@@ -19,6 +19,7 @@
 * Remap a key to two different keys depending on whether it's pressed alone or held.
 * Application-specific remapping. Even if it's not supported by your application, xremap can.
 * Automatically remap newly connected devices by starting xremap with `--watch`.
+* Support [Emacs-like key remapping](example/emacs.yml), including the mark mode.
 
 ## Prerequisite
 
@@ -146,6 +147,10 @@ keymap:
       # execute a command
       MOD1-KEY_XXX:
         launch: ["bash", "-c", "echo hello > /tmp/test"]
+      # let `with_mark` also press a Shift key (useful for Emacs emulation)
+      MOD1-KEY_XXX: { set_mark: true } # use { set_mark: false } to disable it
+      # also press Shift only when { set_mark: true } is used before
+      MOD1-KEY_XXX: { with_mark: MOD2-KEY_YYY }
     application: # Optional
       not: [Application, ...]
       # or

example/emacs.yml

@@ -0,0 +1,60 @@
+# Credit: https://github.com/mooz/xkeysnail/blob/bf3c93b4fe6efd42893db4e6588e5ef1c4909cfb/example/config.py#L62-L125
+keymap:
+  - name: Emacs
+    remap:
+      # Cursor
+      C-b: { with_mark: left }
+      C-f: { with_mark: right }
+      C-p: { with_mark: up }
+      C-n: { with_mark: down }
+      # Forward/Backward word
+      M-b: { with_mark: C-left }
+      M-f: { with_mark: C-right }
+      # Beginning/End of line
+      C-a: { with_mark: home }
+      C-e: { with_mark: end }
+      # Page up/down
+      M-v: { with_mark: pageup }
+      C-v: { with_mark: pagedown }
+      # Beginning/End of file
+      M-Shift-comma: { with_mark: C-home }
+      M-Shift-dot: { with_mark: C-end }
+      # Newline
+      C-m: enter
+      C-j: enter
+      C-o: [enter, left]
+      # Copy
+      C-w: [C-x, { set_mark: false }]
+      M-w: [C-c, { set_mark: false }]
+      C-y: [C-v, { set_mark: false }]
+      # Delete
+      C-d: [delete, { set_mark: false }]
+      M-d: [C-delete, { set_mark: false }]
+      # Kill line
+      C-k: [Shift-end, C-x, { set_mark: false }]
+      # Undo
+      C-slash: [C-z, { set_mark: false }]
+      C-Shift-ro: C-z
+      # Mark
+      C-space: { set_mark: true }
+      # Search
+      C-s: F3
+      C-r: Shift-F3
+      M-Shift-5: C-h
+      # Cancel
+      C-g: [esc, { set_mark: false }]
+      # C-x YYY
+      C-x:
+        remap:
+          # C-x h (select all)
+          h: [C-home, C-a, { set_mark: true }]
+          # C-x C-f (open)
+          C-f: C-o
+          # C-x C-s (save)
+          C-s: C-s
+          # C-x k (kill tab)
+          k: C-f4
+          # C-x C-c (exit)
+          C-c: C-q
+          # C-x u (undo)
+          u: [C-z, { set_mark: false }]

src/config/action.rs

@@ -14,6 +14,10 @@ pub enum Action {
     Remap(HashMap<KeyPress, Vec<Action>>),
     #[serde(deserialize_with = "deserialize_launch")]
     Launch(Vec<String>),
+    #[serde(deserialize_with = "deserialize_with_mark")]
+    WithMark(KeyPress),
+    #[serde(deserialize_with = "deserialize_set_mark")]
+    SetMark(bool),
 }
 
 fn deserialize_remap<'de, D>(deserializer: D) -> Result<HashMap<KeyPress, Vec<Action>>, D::Error>
@@ -42,6 +46,32 @@ where
     Err(de::Error::custom("not a map with a single \"launch\" key"))
 }
 
+fn deserialize_with_mark<'de, D>(deserializer: D) -> Result<KeyPress, D::Error>
+where
+    D: Deserializer<'de>,
+{
+    let mut action = HashMap::<String, KeyPress>::deserialize(deserializer)?;
+    if let Some(key_press) = action.remove("with_mark") {
+        if action.is_empty() {
+            return Ok(key_press);
+        }
+    }
+    Err(de::Error::custom("not a map with a single \"with_mark\" key"))
+}
+
+fn deserialize_set_mark<'de, D>(deserializer: D) -> Result<bool, D::Error>
+where
+    D: Deserializer<'de>,
+{
+    let mut action = HashMap::<String, bool>::deserialize(deserializer)?;
+    if let Some(set) = action.remove("set_mark") {
+        if action.is_empty() {
+            return Ok(set);
+        }
+    }
+    Err(de::Error::custom("not a map with a single \"set_mark\" key"))
+}
+
 // Used only for deserializing Vec<Action>
 #[derive(Deserialize)]
 #[serde(untagged)]

src/config/tests.rs

@@ -114,6 +114,18 @@ fn test_keymap_launch() {
     "#})
 }
 
+#[test]
+fn test_keymap_mark() {
+    assert_parse(indoc! {"
+    keymap:
+      - remap:
+          C-space: { set_mark: true }
+          C-g: [esc, { set_mark: false }]
+          C-b: { with_mark: left }
+          M-b: { with_mark: C-left }
+    "})
+}
+
 fn assert_parse(yaml: &str) {
     let result: Result<Config, Error> = serde_yaml::from_str(&yaml);
     if let Err(e) = result {

src/device.rs

@@ -26,7 +26,7 @@ static MOUSE_BTNS: [&str; 13] = [
     "BTN_RIGHT",
 ];
 
-// Credit: https://github.com/mooz/xkeysnail/blob/master/xkeysnail/output.py#L10-L32
+// Credit: https://github.com/mooz/xkeysnail/blob/bf3c93b4fe6efd42893db4e6588e5ef1c4909cfb/xkeysnail/output.py#L10-L32
 pub fn output_device() -> Result<VirtualDevice, Box<dyn Error>> {
     let mut keys: AttributeSet<Key> = AttributeSet::new();
     for code in Key::KEY_RESERVED.code()..Key::BTN_TRIGGER_HAPPY40.code() {
@@ -183,7 +183,7 @@ fn match_device(path: &str, device: &Device, device_opts: &Vec<String>) -> bool
 }
 
 fn is_keyboard(device: &Device) -> bool {
-    // Credit: https://github.com/mooz/xkeysnail/blob/master/xkeysnail/input.py#L17-L32
+    // Credit: https://github.com/mooz/xkeysnail/blob/bf3c93b4fe6efd42893db4e6588e5ef1c4909cfb/xkeysnail/input.py#L17-L32
     match device.supported_keys() {
         Some(keys) => {
             keys.contains(Key::KEY_SPACE)

src/event_handler.rs

@@ -21,11 +21,12 @@ pub struct EventHandler {
     control: PressState,
     alt: PressState,
     windows: PressState,
-    wm_client: WMClient,
+    application_client: WMClient,
     application_cache: Option<String>,
     multi_purpose_keys: HashMap<Key, MultiPurposeKeyState>,
     override_remap: Option<HashMap<KeyPress, Vec<Action>>>,
     sigaction_set: bool,
+    mark_set: bool,
 }
 
 impl EventHandler {
@@ -36,11 +37,12 @@ impl EventHandler {
             control: PressState::new(false),
             alt: PressState::new(false),
             windows: PressState::new(false),
-            wm_client: build_client(),
+            application_client: build_client(),
             application_cache: None,
             multi_purpose_keys: HashMap::new(),
             override_remap: None,
             sigaction_set: false,
+            mark_set: false,
         }
     }
 
@@ -187,25 +189,7 @@ impl EventHandler {
 
     fn dispatch_action(&mut self, action: &Action) -> Result<(), Box<dyn Error>> {
         match action {
-            Action::KeyPress(key_press) => {
-                let next_shift = self.build_state(Modifier::Shift, key_press.shift);
-                let next_control = self.build_state(Modifier::Control, key_press.control);
-                let next_alt = self.build_state(Modifier::Alt, key_press.alt);
-                let next_windows = self.build_state(Modifier::Windows, key_press.windows);
-
-                let prev_shift = self.send_modifier(Modifier::Shift, &next_shift)?;
-                let prev_control = self.send_modifier(Modifier::Control, &next_control)?;
-                let prev_alt = self.send_modifier(Modifier::Alt, &next_alt)?;
-                let prev_windows = self.send_modifier(Modifier::Windows, &next_windows)?;
-
-                self.send_key(&key_press.key, PRESS)?;
-                self.send_key(&key_press.key, RELEASE)?;
-
-                self.send_modifier(Modifier::Windows, &prev_windows)?;
-                self.send_modifier(Modifier::Alt, &prev_alt)?;
-                self.send_modifier(Modifier::Control, &prev_control)?;
-                self.send_modifier(Modifier::Shift, &prev_shift)?;
-            }
+            Action::KeyPress(key_press) => self.send_key_press(key_press)?,
             Action::Remap(remap) => {
                 let mut override_remap: HashMap<KeyPress, Vec<Action>> = HashMap::new();
                 for (key_press, actions) in remap.iter() {
@@ -214,31 +198,31 @@ impl EventHandler {
                 self.override_remap = Some(override_remap)
             }
             Action::Launch(command) => self.run_command(command.clone()),
+            Action::WithMark(key_press) => self.send_key_press(&self.with_mark(key_press))?,
+            Action::SetMark(set) => self.mark_set = *set,
         }
         Ok(())
     }
 
-    fn run_command(&mut self, command: Vec<String>) {
-        if !self.sigaction_set {
-            // Avoid defunct processes
-            let sig_action = SigAction::new(SigHandler::SigDfl, SaFlags::SA_NOCLDWAIT, SigSet::empty());
-            unsafe {
-                sigaction(signal::SIGCHLD, &sig_action).expect("Failed to register SIGCHLD handler");
-            }
-            self.sigaction_set = true;
-        }
+    fn send_key_press(&mut self, key_press: &KeyPress) -> Result<(), Box<dyn Error>> {
+        let next_shift = self.build_state(Modifier::Shift, key_press.shift);
+        let next_control = self.build_state(Modifier::Control, key_press.control);
+        let next_alt = self.build_state(Modifier::Alt, key_press.alt);
+        let next_windows = self.build_state(Modifier::Windows, key_press.windows);
 
-        debug!("Running command: {:?}", command);
-        match Command::new(&command[0])
-            .args(&command[1..])
-            .stdin(Stdio::null())
-            .stdout(Stdio::null())
-            .stderr(Stdio::null())
-            .spawn()
-        {
-            Ok(child) => debug!("Process spawned: {:?}, pid {}", command, child.id()),
-            Err(e) => error!("Error running command: {:?}", e),
-        }
+        let prev_shift = self.send_modifier(Modifier::Shift, &next_shift)?;
+        let prev_control = self.send_modifier(Modifier::Control, &next_control)?;
+        let prev_alt = self.send_modifier(Modifier::Alt, &next_alt)?;
+        let prev_windows = self.send_modifier(Modifier::Windows, &next_windows)?;
+
+        self.send_key(&key_press.key, PRESS)?;
+        self.send_key(&key_press.key, RELEASE)?;
+
+        self.send_modifier(Modifier::Windows, &prev_windows)?;
+        self.send_modifier(Modifier::Alt, &prev_alt)?;
+        self.send_modifier(Modifier::Control, &prev_control)?;
+        self.send_modifier(Modifier::Shift, &prev_shift)?;
+        Ok(())
     }
 
     fn send_modifier(&mut self, modifier: Modifier, desired: &PressState) -> Result<PressState, Box<dyn Error>> {
@@ -310,10 +294,43 @@ impl EventHandler {
         }
     }
 
+    fn with_mark(&self, key_press: &KeyPress) -> KeyPress {
+        KeyPress {
+            key: key_press.key.clone(),
+            shift: key_press.shift || self.mark_set,
+            control: key_press.shift,
+            alt: key_press.alt,
+            windows: key_press.windows,
+        }
+    }
+
+    fn run_command(&mut self, command: Vec<String>) {
+        if !self.sigaction_set {
+            // Avoid defunct processes
+            let sig_action = SigAction::new(SigHandler::SigDfl, SaFlags::SA_NOCLDWAIT, SigSet::empty());
+            unsafe {
+                sigaction(signal::SIGCHLD, &sig_action).expect("Failed to register SIGCHLD handler");
+            }
+            self.sigaction_set = true;
+        }
+
+        debug!("Running command: {:?}", command);
+        match Command::new(&command[0])
+            .args(&command[1..])
+            .stdin(Stdio::null())
+            .stdout(Stdio::null())
+            .stderr(Stdio::null())
+            .spawn()
+        {
+            Ok(child) => debug!("Process spawned: {:?}, pid {}", command, child.id()),
+            Err(e) => error!("Error running command: {:?}", e),
+        }
+    }
+
     fn match_application(&mut self, application_matcher: &Application) -> bool {
         // Lazily fill the wm_class cache
         if let None = self.application_cache {
-            match self.wm_client.current_application() {
+            match self.application_client.current_application() {
                 Some(application) => self.application_cache = Some(application),
                 None => self.application_cache = Some(String::new()),
             }