config reload: destroy old seat when removed from config

This adds new sway_seat_destroy and sway_cursor_destroy helpers
and compare new and old config on free

include/sway/input/cursor.h

@@ -25,6 +25,7 @@ struct sway_cursor {
 	struct wl_listener request_set_cursor;
 };
 
+void sway_cursor_destroy(struct sway_cursor *cursor);
 struct sway_cursor *sway_cursor_create(struct sway_seat *seat);
 
 #endif

include/sway/input/input-manager.h

@@ -46,4 +46,6 @@ void sway_input_manager_apply_seat_config(struct sway_input_manager *input,
 struct sway_seat *sway_input_manager_get_default_seat(
 		struct sway_input_manager *input);
 
+struct sway_seat *input_manager_get_seat(struct sway_input_manager *input,
+		const char *seat_name);
 #endif

include/sway/input/seat.h

@@ -29,6 +29,8 @@ struct sway_seat {
 struct sway_seat *sway_seat_create(struct sway_input_manager *input,
 		const char *seat_name);
 
+void sway_seat_destroy(struct sway_seat *seat);
+
 void sway_seat_add_device(struct sway_seat *seat,
 		struct sway_input_device *device);
 

sway/config.c

@@ -21,6 +21,7 @@
 #endif
 #include <wlr/types/wlr_output.h>
 #include "sway/input/input-manager.h"
+#include "sway/input/seat.h"
 #include "sway/commands.h"
 #include "sway/config.h"
 #include "sway/layout.h"
@@ -109,6 +110,23 @@ void free_config(struct sway_config *config) {
 	free(config);
 }
 
+static void destroy_removed_seats(struct sway_config *old_config,
+		struct sway_config *new_config) {
+	struct seat_config *seat_config;
+	struct sway_seat *seat;
+	int i;
+	for (i = 0; i < old_config->seat_configs->length; i++) {
+		seat_config = old_config->seat_configs->items[i];
+		/* Also destroy seats that aren't present in new config */
+		if (new_config && list_seq_find(new_config->seat_configs,
+				seat_name_cmp, seat_config->name) < 0) {
+			seat = input_manager_get_seat(input_manager,
+				seat_config->name);
+			sway_seat_destroy(seat);
+		}
+	}
+}
+
 static void config_defaults(struct sway_config *config) {
 	if (!(config->symbols = create_list())) goto cleanup;
 	if (!(config->modes = create_list())) goto cleanup;
@@ -382,6 +400,7 @@ bool load_main_config(const char *file, bool is_active) {
 	}
 
 	if (old_config) {
+		destroy_removed_seats(old_config, config);
 		free_config(old_config);
 	}
 	config->reading = false;

sway/input/cursor.c

@@ -149,6 +149,16 @@ static void handle_request_set_cursor(struct wl_listener *listener,
 	wlr_log(L_DEBUG, "TODO: handle request set cursor event: %p", event);
 }
 
+void sway_cursor_destroy(struct sway_cursor *cursor) {
+	if (!cursor) {
+		return;
+	}
+
+	wlr_xcursor_manager_destroy(cursor->xcursor_manager);
+	wlr_cursor_destroy(cursor->cursor);
+	free(cursor);
+}
+
 struct sway_cursor *sway_cursor_create(struct sway_seat *seat) {
 	struct sway_cursor *cursor = calloc(1, sizeof(struct sway_cursor));
 	if (!sway_assert(cursor, "could not allocate sway cursor")) {

sway/input/input-manager.c

@@ -23,7 +23,7 @@ struct sway_input_manager *input_manager;
 struct input_config *current_input_config = NULL;
 struct seat_config *current_seat_config = NULL;
 
-static struct sway_seat *input_manager_get_seat(
+struct sway_seat *input_manager_get_seat(
 		struct sway_input_manager *input, const char *seat_name) {
 	struct sway_seat *seat = NULL;
 	wl_list_for_each(seat, &input->seats, link) {

sway/input/seat.c

@@ -21,6 +21,16 @@ static void seat_device_destroy(struct sway_seat_device *seat_device) {
 	free(seat_device);
 }
 
+void sway_seat_destroy(struct sway_seat *seat) {
+	struct sway_seat_device *seat_device, *next;
+	wl_list_for_each_safe(seat_device, next, &seat->devices, link) {
+		seat_device_destroy(seat_device);
+	}
+	sway_cursor_destroy(seat->cursor);
+	wl_list_remove(&seat->link);
+	wlr_seat_destroy(seat->wlr_seat);
+}
+
 struct sway_seat *sway_seat_create(struct sway_input_manager *input,
 		const char *seat_name) {
 	struct sway_seat *seat = calloc(1, sizeof(struct sway_seat));