input/keyboard: send released only if pressed sent

This keeps track of whether surfaces received a key press event and
will only send a key release event if the pressed event was sent. This
also requires changing the keycodes that are sent via wl_keyboard_enter
to only include those that were previously sent. This makes it so
surfaces do not receive key release events for keys that they never
received a key press for and makes it so switching focus doesn't leak
keycodes that were consumed by bindings.

include/sway/input/keyboard.h

@@ -60,6 +60,7 @@ struct sway_keyboard {
 	struct sway_shortcut_state state_keysyms_translated;
 	struct sway_shortcut_state state_keysyms_raw;
 	struct sway_shortcut_state state_keycodes;
+	struct sway_shortcut_state state_pressed_sent;
 	struct sway_binding *held_binding;
 
 	struct wl_event_source *key_repeat_source;

sway/input/keyboard.c

@@ -69,8 +69,9 @@ int get_modifier_names(const char **names, uint32_t modifier_masks) {
 /**
  * Remove all key ids associated to a keycode from the list of pressed keys
  */
-static void state_erase_key(struct sway_shortcut_state *state,
+static bool state_erase_key(struct sway_shortcut_state *state,
 		uint32_t keycode) {
+	bool found = false;
 	size_t j = 0;
 	for (size_t i = 0; i < state->npressed; ++i) {
 		if (i > j) {
@@ -79,6 +80,8 @@ static void state_erase_key(struct sway_shortcut_state *state,
 		}
 		if (state->pressed_keycodes[i] != keycode) {
 			++j;
+		} else {
+			found = true;
 		}
 	}
 	while(state->npressed > j) {
@@ -87,6 +90,7 @@ static void state_erase_key(struct sway_shortcut_state *state,
 		state->pressed_keycodes[state->npressed] = 0;
 	}
 	state->current_key = 0;
+	return found;
 }
 
 /**
@@ -117,7 +121,7 @@ static void state_add_key(struct sway_shortcut_state *state,
 /**
  * Update the shortcut model state in response to new input
  */
-static void update_shortcut_state(struct sway_shortcut_state *state,
+static bool update_shortcut_state(struct sway_shortcut_state *state,
 		struct wlr_event_keyboard_key *event, uint32_t new_key,
 		uint32_t raw_modifiers) {
 	bool last_key_was_a_modifier = raw_modifiers != state->last_raw_modifiers;
@@ -133,8 +137,10 @@ static void update_shortcut_state(struct sway_shortcut_state *state,
 		state_add_key(state, event->keycode, new_key);
 		state->last_keycode = event->keycode;
 	} else {
-		state_erase_key(state, event->keycode);
+		return state_erase_key(state, event->keycode);
 	}
+
+	return false;
 }
 
 /**
@@ -430,9 +436,13 @@ static void handle_keyboard_key(struct wl_listener *listener, void *data) {
 	}
 
 	if (!handled || event->state == WLR_KEY_RELEASED) {
-		wlr_seat_set_keyboard(wlr_seat, wlr_device);
-		wlr_seat_keyboard_notify_key(wlr_seat, event->time_msec,
-				event->keycode, event->state);
+		bool pressed_sent = update_shortcut_state(
+				&keyboard->state_pressed_sent, event, (uint32_t)keycode, 0);
+		if (pressed_sent || event->state == WLR_KEY_PRESSED) {
+			wlr_seat_set_keyboard(wlr_seat, wlr_device);
+			wlr_seat_keyboard_notify_key(wlr_seat, event->time_msec,
+					event->keycode, event->state);
+		}
 	}
 
 	transaction_commit_dirty();

sway/input/seat.c

@@ -1,4 +1,5 @@
 #define _POSIX_C_SOURCE 200809L
+#include <assert.h>
 #include <linux/input-event-codes.h>
 #include <string.h>
 #include <strings.h>
@@ -85,6 +86,38 @@ static void seat_send_activate(struct sway_node *node, struct sway_seat *seat) {
 	}
 }
 
+static struct sway_keyboard *sway_keyboard_for_wlr_keyboard(
+		struct sway_seat *seat, struct wlr_keyboard *wlr_keyboard) {
+	struct sway_seat_device *seat_device;
+	wl_list_for_each(seat_device, &seat->devices, link) {
+		struct sway_input_device *input_device = seat_device->input_device;
+		if (input_device->wlr_device->type != WLR_INPUT_DEVICE_KEYBOARD) {
+			continue;
+		}
+		if (input_device->wlr_device->keyboard == wlr_keyboard) {
+			return seat_device->keyboard;
+		}
+	}
+	return NULL;
+}
+
+static void seat_keyboard_notify_enter(struct sway_seat *seat,
+		struct wlr_surface *surface) {
+	struct wlr_keyboard *keyboard = wlr_seat_get_keyboard(seat->wlr_seat);
+	if (!keyboard) {
+		wlr_seat_keyboard_notify_enter(seat->wlr_seat, surface, NULL, 0, NULL);
+		return;
+	}
+
+	struct sway_keyboard *sway_keyboard =
+		sway_keyboard_for_wlr_keyboard(seat, keyboard);
+	assert(sway_keyboard && "Cannot find sway_keyboard for seat keyboard");
+
+	struct sway_shortcut_state *state = &sway_keyboard->state_pressed_sent;
+	wlr_seat_keyboard_notify_enter(seat->wlr_seat, surface,
+			state->pressed_keycodes, state->npressed, &keyboard->modifiers);
+}
+
 /**
  * If con is a view, set it as active and enable keyboard input.
  * If con is a container, set all child views as active and don't enable
@@ -103,15 +136,8 @@ static void seat_send_focus(struct sway_node *node, struct sway_seat *seat) {
 			wlr_xwayland_set_seat(xwayland, seat->wlr_seat);
 		}
 #endif
-		struct wlr_keyboard *keyboard = wlr_seat_get_keyboard(seat->wlr_seat);
-		if (keyboard) {
-			wlr_seat_keyboard_notify_enter(seat->wlr_seat,
-					view->surface, keyboard->keycodes,
-					keyboard->num_keycodes, &keyboard->modifiers);
-		} else {
-			wlr_seat_keyboard_notify_enter(
-					seat->wlr_seat, view->surface, NULL, 0, NULL);
-		}
+
+		seat_keyboard_notify_enter(seat, view->surface);
 
 		struct wlr_pointer_constraint_v1 *constraint =
 			wlr_pointer_constraints_v1_constraint_for_surface(
@@ -578,8 +604,6 @@ static void seat_configure_keyboard(struct sway_seat *seat,
 	if (!seat_device->keyboard) {
 		sway_keyboard_create(seat, seat_device);
 	}
-	struct wlr_keyboard *wlr_keyboard =
-		seat_device->input_device->wlr_device->keyboard;
 	sway_keyboard_configure(seat_device->keyboard);
 	wlr_seat_set_keyboard(seat->wlr_seat,
 			seat_device->input_device->wlr_device);
@@ -587,9 +611,7 @@ static void seat_configure_keyboard(struct sway_seat *seat,
 	if (focus && node_is_view(focus)) {
 		// force notify reenter to pick up the new configuration
 		wlr_seat_keyboard_clear_focus(seat->wlr_seat);
-		wlr_seat_keyboard_notify_enter(seat->wlr_seat,
-				focus->sway_container->view->surface, wlr_keyboard->keycodes,
-				wlr_keyboard->num_keycodes, &wlr_keyboard->modifiers);
+		seat_keyboard_notify_enter(seat, focus->sway_container->view->surface);
 	}
 }
 
@@ -1049,13 +1071,7 @@ void seat_set_focus_surface(struct sway_seat *seat,
 		seat_send_unfocus(focus, seat);
 		seat->has_focus = false;
 	}
-	struct wlr_keyboard *keyboard = wlr_seat_get_keyboard(seat->wlr_seat);
-	if (keyboard) {
-		wlr_seat_keyboard_notify_enter(seat->wlr_seat, surface,
-			keyboard->keycodes, keyboard->num_keycodes, &keyboard->modifiers);
-	} else {
-		wlr_seat_keyboard_notify_enter(seat->wlr_seat, surface, NULL, 0, NULL);
-	}
+	seat_keyboard_notify_enter(seat, surface);
 }
 
 void seat_set_focus_layer(struct sway_seat *seat,