keyboard: set keyboard layout on reconfigure

If keyboard-layout-per-toplevel-window is used, reset the group (index)
for each window on --reconfigure whenever the keymap has changed.

Refactor to use a common configure function for reconfigure and
keyboard-group creation.

Co-authored-by: @johanmalm

Fixes #1407

include/input/keyboard.h

@@ -9,8 +9,11 @@ struct seat;
 struct keyboard;
 struct wlr_keyboard;
 
-void keyboard_init(struct seat *seat);
+void keyboard_configure(struct seat *seat, struct wlr_keyboard *kb,
-void keyboard_finish(struct seat *seat);
+	bool is_virtual);
+
+void keyboard_group_init(struct seat *seat);
+void keyboard_group_finish(struct seat *seat);
 
 void keyboard_setup_handlers(struct keyboard *keyboard);
 void keyboard_set_numlock(struct wlr_keyboard *keyboard);

src/input/input.c

@@ -7,12 +7,12 @@ void
 input_handlers_init(struct seat *seat)
 {
 	cursor_init(seat);
-	keyboard_init(seat);
+	keyboard_group_init(seat);
 }
 
 void
 input_handlers_finish(struct seat *seat)
 {
 	cursor_finish(seat);
-	keyboard_finish(seat);
+	keyboard_group_finish(seat);
 }

src/input/keyboard.c

@@ -592,27 +592,74 @@ keyboard_update_layout(struct seat *seat, xkb_layout_index_t layout)
 		kb->modifiers.latched, kb->modifiers.locked, layout);
 }
 
-void
+static void
-keyboard_init(struct seat *seat)
+reset_window_keyboard_layout_groups(struct server *server)
+{
+	if (!rc.kb_layout_per_window) {
+		return;
+	}
+
+	/*
+	 * Technically it would be possible to reconcile previous group indices
+	 * to new group ones if particular layouts exist in both old and new,
+	 * but let's keep it simple for now and just reset them all.
+	 */
+	struct view *view;
+	for_each_view(view, &server->views, LAB_VIEW_CRITERIA_NONE) {
+		view->keyboard_layout = 0;
+	}
+
+	struct view *active_view = server->active_view;
+	if (!active_view) {
+		return;
+	}
+	keyboard_update_layout(&server->seat, active_view->keyboard_layout);
+}
+
+/*
+ * Set layout based on environment variables XKB_DEFAULT_LAYOUT,
+ * XKB_DEFAULT_OPTIONS, and friends.
+ */
+static void
+set_layout(struct server *server, struct wlr_keyboard *kb)
 {
-	seat->keyboard_group = wlr_keyboard_group_create();
-	struct wlr_keyboard *kb = &seat->keyboard_group->keyboard;
 	struct xkb_rule_names rules = { 0 };
 	struct xkb_context *context = xkb_context_new(XKB_CONTEXT_NO_FLAGS);
 	struct xkb_keymap *keymap = xkb_map_new_from_names(context, &rules,
 		XKB_KEYMAP_COMPILE_NO_FLAGS);
 	if (keymap) {
+		if (!wlr_keyboard_keymaps_match(kb->keymap, keymap)) {
 			wlr_keyboard_set_keymap(kb, keymap);
+			reset_window_keyboard_layout_groups(server);
+		}
 		xkb_keymap_unref(keymap);
 	} else {
 		wlr_log(WLR_ERROR, "Failed to create xkb keymap");
 	}
 	xkb_context_unref(context);
-	wlr_keyboard_set_repeat_info(kb, rc.repeat_rate, rc.repeat_delay);
+}
 
+void
+keyboard_configure(struct seat *seat, struct wlr_keyboard *kb, bool is_virtual)
+{
+	if (!is_virtual) {
+		set_layout(seat->server, kb);
+	}
+	wlr_keyboard_set_repeat_info(kb, rc.repeat_rate, rc.repeat_delay);
 	keybind_update_keycodes(seat->server);
 }
 
+void
+keyboard_group_init(struct seat *seat)
+{
+	if (seat->keyboard_group) {
+		return;
+	}
+	seat->keyboard_group = wlr_keyboard_group_create();
+	keyboard_configure(seat, &seat->keyboard_group->keyboard,
+		/* is_virtual */ false);
+}
+
 void
 keyboard_setup_handlers(struct keyboard *keyboard)
 {
@@ -625,7 +672,7 @@ keyboard_setup_handlers(struct keyboard *keyboard)
 }
 
 void
-keyboard_finish(struct seat *seat)
+keyboard_group_finish(struct seat *seat)
 {
 	/*
 	 * All keyboard listeners must be removed before this to avoid use after

src/seat.c

@@ -506,13 +506,16 @@ seat_finish(struct server *server)
 }
 
 static void
-configure_keyboard(struct wlr_input_device *device)
+configure_keyboard(struct seat *seat, struct input *input)
 {
+	struct wlr_input_device *device = input->wlr_input_device;
 	assert(device->type == WLR_INPUT_DEVICE_KEYBOARD);
+	struct keyboard *keyboard = (struct keyboard *)input;
 	struct wlr_keyboard *kb = wlr_keyboard_from_input_device(device);
-	wlr_keyboard_set_repeat_info(kb, rc.repeat_rate, rc.repeat_delay);
+	keyboard_configure(seat, kb, keyboard->is_virtual);
 }
 
+/* This is called on SIGHUP (generally in response to labwc --reconfigure */
 void
 seat_reconfigure(struct server *server)
 {
@@ -521,7 +524,7 @@ seat_reconfigure(struct server *server)
 	wl_list_for_each(input, &seat->inputs, link) {
 		switch (input->wlr_input_device->type) {
 		case WLR_INPUT_DEVICE_KEYBOARD:
-			configure_keyboard(input->wlr_input_device);
+			configure_keyboard(seat, input);
 			break;
 		case WLR_INPUT_DEVICE_POINTER:
 			configure_libinput(input->wlr_input_device);

src/server.c

@@ -61,7 +61,6 @@ 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