keyboard translate keysyms

1 files changed, 144 insertions, 3 deletions

diff --git a/sway/input/keyboard.c b/sway/input/keyboard.c
index 724941d8..25def7ac 100644
--- a/sway/input/keyboard.c
+++ b/sway/input/keyboard.c
@@ -3,6 +3,121 @@
 #include "sway/input/input-manager.h"
 #include "log.h"
 
+/*
+ * Get keysyms and modifiers from the keyboard as xkb sees them.
+ *
+ * This uses the xkb keysyms translation based on pressed modifiers and clears
+ * the consumed modifiers from the list of modifiers passed to keybind
+ * detection.
+ *
+ * On US layout, pressing Alt+Shift+2 will trigger Alt+@.
+ */
+static size_t keyboard_keysyms_translated(struct sway_keyboard *keyboard,
+                xkb_keycode_t keycode, const xkb_keysym_t **keysyms,
+                uint32_t *modifiers) {
+        struct wlr_input_device *device =
+                keyboard->seat_device->input_device->wlr_device;
+        *modifiers = wlr_keyboard_get_modifiers(device->keyboard);
+        xkb_mod_mask_t consumed = xkb_state_key_get_consumed_mods2(
+                device->keyboard->xkb_state, keycode, XKB_CONSUMED_MODE_XKB);
+        *modifiers = *modifiers & ~consumed;
+
+        return xkb_state_key_get_syms(device->keyboard->xkb_state,
+                keycode, keysyms);
+}
+
+/*
+ * Get keysyms and modifiers from the keyboard as if modifiers didn't change
+ * keysyms.
+ *
+ * This avoids the xkb keysym translation based on modifiers considered pressed
+ * in the state.
+ *
+ * This will trigger keybinds such as Alt+Shift+2.
+ */
+static size_t keyboard_keysyms_raw(struct sway_keyboard *keyboard,
+                xkb_keycode_t keycode, const xkb_keysym_t **keysyms,
+                uint32_t *modifiers) {
+        struct wlr_input_device *device =
+                keyboard->seat_device->input_device->wlr_device;
+        *modifiers = wlr_keyboard_get_modifiers(device->keyboard);
+
+        xkb_layout_index_t layout_index = xkb_state_key_get_layout(
+                device->keyboard->xkb_state, keycode);
+        return xkb_keymap_key_get_syms_by_level(device->keyboard->keymap,
+                keycode, layout_index, 0, keysyms);
+}
+
+static ssize_t pressed_keysyms_index(xkb_keysym_t *pressed_keysyms,
+                xkb_keysym_t keysym) {
+        for (size_t i = 0; i < SWAY_KEYBOARD_PRESSED_KEYSYMS_CAP; ++i) {
+                if (pressed_keysyms[i] == keysym) {
+                        return i;
+                }
+        }
+        return -1;
+}
+
+static size_t pressed_keysyms_length(xkb_keysym_t *pressed_keysyms) {
+        size_t n = 0;
+        for (size_t i = 0; i < SWAY_KEYBOARD_PRESSED_KEYSYMS_CAP; ++i) {
+                if (pressed_keysyms[i] != XKB_KEY_NoSymbol) {
+                        ++n;
+                }
+        }
+        return n;
+}
+
+static void pressed_keysyms_add(xkb_keysym_t *pressed_keysyms,
+                xkb_keysym_t keysym) {
+        ssize_t i = pressed_keysyms_index(pressed_keysyms, keysym);
+        if (i < 0) {
+                i = pressed_keysyms_index(pressed_keysyms, XKB_KEY_NoSymbol);
+                if (i >= 0) {
+                        pressed_keysyms[i] = keysym;
+                }
+        }
+}
+
+static void pressed_keysyms_remove(xkb_keysym_t *pressed_keysyms,
+                xkb_keysym_t keysym) {
+        ssize_t i = pressed_keysyms_index(pressed_keysyms, keysym);
+        if (i >= 0) {
+                pressed_keysyms[i] = XKB_KEY_NoSymbol;
+        }
+}
+
+static bool keysym_is_modifier(xkb_keysym_t keysym) {
+        switch (keysym) {
+        case XKB_KEY_Shift_L: case XKB_KEY_Shift_R:
+        case XKB_KEY_Control_L: case XKB_KEY_Control_R:
+        case XKB_KEY_Caps_Lock:
+        case XKB_KEY_Shift_Lock:
+        case XKB_KEY_Meta_L: case XKB_KEY_Meta_R:
+        case XKB_KEY_Alt_L: case XKB_KEY_Alt_R:
+        case XKB_KEY_Super_L: case XKB_KEY_Super_R:
+        case XKB_KEY_Hyper_L: case XKB_KEY_Hyper_R:
+                return true;
+        default:
+                return false;
+        }
+}
+
+static void pressed_keysyms_update(xkb_keysym_t *pressed_keysyms,
+                const xkb_keysym_t *keysyms, size_t keysyms_len,
+                enum wlr_key_state state) {
+        for (size_t i = 0; i < keysyms_len; ++i) {
+                if (keysym_is_modifier(keysyms[i])) {
+                        continue;
+                }
+                if (state == WLR_KEY_PRESSED) {
+                        pressed_keysyms_add(pressed_keysyms, keysyms[i]);
+                } else { // WLR_KEY_RELEASED
+                        pressed_keysyms_remove(pressed_keysyms, keysyms[i]);
+                }
+        }
+}
+
 static void handle_keyboard_key(struct wl_listener *listener, void *data) {
         struct sway_keyboard *keyboard =
                 wl_container_of(listener, keyboard, keyboard_key);
@@ -10,9 +125,35 @@ static void handle_keyboard_key(struct wl_listener *listener, void *data) {
         struct wlr_input_device *wlr_device =
                 keyboard->seat_device->input_device->wlr_device;
         struct wlr_event_keyboard_key *event = data;
-        wlr_seat_set_keyboard(wlr_seat, wlr_device);
-        wlr_seat_keyboard_notify_key(wlr_seat, event->time_msec,
-                event->keycode, event->state);
+
+        xkb_keycode_t keycode = event->keycode + 8;
+        bool handled = false;
+        uint32_t modifiers;
+        const xkb_keysym_t *keysyms;
+        size_t keysyms_len;
+
+        // handle translated keysyms
+        keysyms_len = keyboard_keysyms_translated(keyboard, keycode, &keysyms,
+                &modifiers);
+        pressed_keysyms_update(keyboard->pressed_keysyms_translated, keysyms,
+                keysyms_len, event->state);
+        if (event->state == WLR_KEY_PRESSED) {
+                // TODO execute binding
+        }
+
+        // Handle raw keysyms
+        keysyms_len = keyboard_keysyms_raw(keyboard, keycode, &keysyms, &modifiers);
+        pressed_keysyms_update(keyboard->pressed_keysyms_raw, keysyms, keysyms_len,
+                event->state);
+        if (event->state == WLR_KEY_PRESSED && !handled) {
+                // TODO execute binding
+        }
+
+        if (!handled) {
+                wlr_seat_set_keyboard(wlr_seat, wlr_device);
+                wlr_seat_keyboard_notify_key(wlr_seat, event->time_msec,
+                                event->keycode, event->state);
+        }
 }
 
 static void handle_keyboard_modifiers(struct wl_listener *listener,