keybinds: prefer keycodes over keysyms

This allows keyboard layout agnostic keybinds
in a multi layout configuration.

Fixes: #1069

include/config/keybind.h

@@ -6,11 +6,17 @@
 #include <xkbcommon/xkbcommon.h>
 
 #define MAX_KEYSYMS 32
+#define MAX_KEYCODES 16
+
+struct server;
 
 struct keybind {
 	uint32_t modifiers;
 	xkb_keysym_t *keysyms;
 	size_t keysyms_len;
+	xkb_keycode_t keycodes[MAX_KEYCODES];
+	size_t keycodes_len;
+	int keycodes_layout;
 	struct wl_list actions;  /* struct action.link */
 	struct wl_list link;     /* struct rcxml.keybinds */
 };
@@ -30,4 +36,5 @@ uint32_t parse_modifier(const char *symname);
 
 bool keybind_the_same(struct keybind *a, struct keybind *b);
 
+void keybind_update_keycodes(struct server *server);
 #endif /* LABWC_KEYBIND_H */

src/config/keybind.c

@@ -10,6 +10,7 @@
 #include "common/mem.h"
 #include "config/keybind.h"
 #include "config/rcxml.h"
+#include "labwc.h"
 
 uint32_t
 parse_modifier(const char *symname)
@@ -42,6 +43,70 @@ keybind_the_same(struct keybind *a, struct keybind *b)
 	return true;
 }
 
+static void
+update_keycodes_iter(struct xkb_keymap *keymap, xkb_keycode_t key, void *data)
+{
+	struct keybind *keybind;
+	const xkb_keysym_t *syms;
+	xkb_layout_index_t layout = *(xkb_layout_index_t *)data;
+	int nr_syms = xkb_keymap_key_get_syms_by_level(keymap, key, layout, 0, &syms);
+	if (!nr_syms) {
+		return;
+	}
+	wl_list_for_each(keybind, &rc.keybinds, link) {
+		if (keybind->keycodes_layout >= 0
+				&& (xkb_layout_index_t)keybind->keycodes_layout != layout) {
+			/* Prevent storing keycodes from multiple layouts */
+			continue;
+		}
+		for (int i = 0; i < nr_syms; i++) {
+			xkb_keysym_t sym = syms[i];
+			for (size_t j = 0; j < keybind->keysyms_len; j++) {
+				if (sym != keybind->keysyms[j]) {
+					continue;
+				}
+				/* Found keycode for sym */
+				if (keybind->keycodes_len == MAX_KEYCODES) {
+					wlr_log(WLR_ERROR,
+						"Already stored %lu keycodes for keybind",
+						keybind->keycodes_len);
+					break;
+				}
+				bool keycode_exists = false;
+				for (size_t k = 0; k < keybind->keycodes_len; k++) {
+					if (keybind->keycodes[k] == key) {
+						keycode_exists = true;
+						break;
+					}
+				}
+				if (keycode_exists) {
+					continue;
+				}
+				keybind->keycodes[keybind->keycodes_len++] = key;
+				keybind->keycodes_layout = layout;
+			}
+		}
+	}
+}
+
+void
+keybind_update_keycodes(struct server *server)
+{
+	struct xkb_state *state = server->seat.keyboard_group->keyboard.xkb_state;
+	struct xkb_keymap *keymap = xkb_state_get_keymap(state);
+
+	struct keybind *keybind;
+	wl_list_for_each(keybind, &rc.keybinds, link) {
+		keybind->keycodes_len = 0;
+		keybind->keycodes_layout = -1;
+	}
+	xkb_layout_index_t layouts = xkb_keymap_num_layouts(keymap);
+	for (xkb_layout_index_t i = 0; i < layouts; i++) {
+		wlr_log(WLR_DEBUG, "Found layout %s", xkb_keymap_layout_get_name(keymap, i));
+		xkb_keymap_key_for_each(keymap, update_keycodes_iter, &i);
+	}
+}
+
 struct keybind *
 keybind_create(const char *keybind)
 {

src/keyboard.c

@@ -86,7 +86,7 @@ keyboard_modifiers_notify(struct wl_listener *listener, void *data)
 }
 
 static bool
-handle_keybinding(struct server *server, uint32_t modifiers, xkb_keysym_t sym)
+handle_keybinding(struct server *server, uint32_t modifiers, xkb_keysym_t sym, xkb_keycode_t code)
 {
 	struct keybind *keybind;
 	wl_list_for_each(keybind, &rc.keybinds, link) {
@@ -98,11 +98,23 @@ handle_keybinding(struct server *server, uint32_t modifiers, xkb_keysym_t sym)
 				&& !actions_contain_toggle_keybinds(&keybind->actions)) {
 			continue;
 		}
-		for (size_t i = 0; i < keybind->keysyms_len; i++) {
-			if (xkb_keysym_to_lower(sym) == keybind->keysyms[i]) {
-				key_state_store_pressed_keys_as_bound();
-				actions_run(NULL, server, &keybind->actions, 0);
-				return true;
+		if (sym == XKB_KEY_NoSymbol) {
+			/* Use keycodes */
+			for (size_t i = 0; i < keybind->keycodes_len; i++) {
+				if (keybind->keycodes[i] == code) {
+					key_state_store_pressed_keys_as_bound();
+					actions_run(NULL, server, &keybind->actions, 0);
+					return true;
+				}
+			}
+		} else {
+			/* Use syms */
+			for (size_t i = 0; i < keybind->keysyms_len; i++) {
+				if (xkb_keysym_to_lower(sym) == keybind->keysyms[i]) {
+					key_state_store_pressed_keys_as_bound();
+					actions_run(NULL, server, &keybind->actions, 0);
+					return true;
+				}
 			}
 		}
 	}
@@ -301,16 +313,58 @@ handle_compositor_keybindings(struct keyboard *keyboard,
 		goto out;
 	}
 
-	/* Handle compositor key bindings */
+	/*
+	 * Handle compositor keybinds
+	 *
+	 * When matching against keybinds, we process the input keys in the
+	 * following order of precedence:
+	 *   a. Keycodes (of physical keys) (not if keybind is layoutDependent)
+	 *   b. Translated keysyms (taking into account modifiers, so if Shift+1
+	 *      were pressed on a us keyboard, the keysym would be '!')
+	 *   c. Raw keysyms (ignoring modifiers such as shift, so in the above
+	 *      example the keysym would just be '1')
+	 *
+	 * The reasons for this approach are:
+	 *   1. To make keybinds keyboard-layout agnostic (by checking keycodes
+	 *      before keysyms). This means that in a multi-layout situation,
+	 *      keybinds work regardless of which layout is active at the time
+	 *      of the key-press.
+	 *   2. To support keybinds relating to keysyms that are only available
+	 *      in a particular layout, for example å, ä and ö.
+	 *   3. To support keybinds that are only valid with a modifier, for
+	 *      example the numpad keys with NumLock enabled: KP_x. These would
+	 *      only be matched by the translated keysyms.
+	 *   4. To support keybinds such as `S-1` (by checking raw keysyms).
+	 *
+	 * Reason 4 will also be satisfied by matching the keycodes. However,
+	 * when a keybind is configured to be layoutDependent we still need
+	 * the raw keysym fallback.
+	 */
+
 	if (event->state == WL_KEYBOARD_KEY_STATE_PRESSED) {
-		for (int i = 0; i < translated.nr_syms; i++) {
-			handled |= handle_keybinding(server, modifiers, translated.syms[i]);
-		}
+		/* First try keycodes */
+		handled |= handle_keybinding(server, modifiers, XKB_KEY_NoSymbol, keycode);
 		if (handled) {
+			wlr_log(WLR_DEBUG, "keycodes matched");
 			goto out;
 		}
+
+		/* Then fall back to keysyms */
+		for (int i = 0; i < translated.nr_syms; i++) {
+			handled |= handle_keybinding(server, modifiers,
+				translated.syms[i], keycode);
+		}
+		if (handled) {
+			wlr_log(WLR_DEBUG, "translated keysyms matched");
+			goto out;
+		}
+
+		/* And finally test for keysyms without modifier */
 		for (int i = 0; i < raw.nr_syms; i++) {
-			handled |= handle_keybinding(server, modifiers, raw.syms[i]);
+			handled |= handle_keybinding(server, modifiers, raw.syms[i], keycode);
+		}
+		if (handled) {
+			wlr_log(WLR_DEBUG, "raw keysyms matched");
 		}
 	}
 
@@ -413,6 +467,8 @@ keyboard_init(struct seat *seat)
 	}
 	xkb_context_unref(context);
 	wlr_keyboard_set_repeat_info(kb, rc.repeat_rate, rc.repeat_delay);
+
+	keybind_update_keycodes(seat->server);
 }
 
 void

src/server.c

@@ -57,6 +57,7 @@ reload_config_and_theme(void)
 	regions_reconfigure(g_server);
 	resize_indicator_reconfigure(g_server);
 	kde_server_decoration_update_default();
+	keybind_update_keycodes(g_server);
 }
 
 static int