Merge pull request #80104 from bruvzg/freedesktop_native_file_dialog

[Linux/Freedesktop] Implement native file selection dialog support.

doc/classes/DisplayServer.xml

@@ -121,7 +121,9 @@
 				Displays OS native dialog for selecting files or directories in the file system.
 				Callbacks have the following arguments: [code]bool status, PackedStringArray selected_paths[/code].
 				[b]Note:[/b] This method is implemented if the display server has the [code]FEATURE_NATIVE_DIALOG[/code] feature.
-				[b]Note:[/b] This method is implemented on Windows and macOS.
+				[b]Note:[/b] This method is implemented on Linux, Windows and macOS.
+				[b]Note:[/b] [param current_directory] might be ignored.
+				[b]Note:[/b] On Linux, [param show_hidden] is ignored.
 				[b]Note:[/b] On macOS, native file dialogs have no title.
 				[b]Note:[/b] On macOS, sandboxed apps will save security-scoped bookmarks to retain access to the opened folders across multiple sessions. Use [method OS.get_granted_permissions] to get a list of saved bookmarks.
 			</description>

doc/classes/OS.xml

@@ -538,7 +538,7 @@
 			<return type="bool" />
 			<description>
 				Returns [code]true[/code] if application is running in the sandbox.
-				[b]Note:[/b] This method is implemented on macOS.
+				[b]Note:[/b] This method is implemented on macOS and Linux.
 			</description>
 		</method>
 		<method name="is_stdout_verbose" qualifiers="const">

platform/linuxbsd/freedesktop_portal_desktop.cpp

@@ -32,6 +32,7 @@
 
 #ifdef DBUS_ENABLED
 
+#include "core/crypto/crypto_core.h"
 #include "core/error/error_macros.h"
 #include "core/os/os.h"
 #include "core/string/ustring.h"
@@ -43,12 +44,15 @@
 #include <dbus/dbus.h>
 #endif
 
+#include <unistd.h>
+
 #define BUS_OBJECT_NAME "org.freedesktop.portal.Desktop"
 #define BUS_OBJECT_PATH "/org/freedesktop/portal/desktop"
 
 #define BUS_INTERFACE_SETTINGS "org.freedesktop.portal.Settings"
+#define BUS_INTERFACE_FILE_CHOOSER "org.freedesktop.portal.FileChooser"
 
-static bool try_parse_variant(DBusMessage *p_reply_message, int p_type, void *r_value) {
+bool FreeDesktopPortalDesktop::try_parse_variant(DBusMessage *p_reply_message, int p_type, void *r_value) {
 	DBusMessageIter iter[3];
 
 	dbus_message_iter_init(p_reply_message, &iter[0]);
@@ -80,11 +84,11 @@ bool FreeDesktopPortalDesktop::read_setting(const char *p_namespace, const char
 
 	DBusConnection *bus = dbus_bus_get(DBUS_BUS_SESSION, &error);
 	if (dbus_error_is_set(&error)) {
-		dbus_error_free(&error);
-		unsupported = true;
 		if (OS::get_singleton()->is_stdout_verbose()) {
-			ERR_PRINT(String() + "Error opening D-Bus connection: " + error.message);
+			ERR_PRINT(vformat("Error opening D-Bus connection: %s", error.message));
 		}
+		dbus_error_free(&error);
+		unsupported = true;
 		return false;
 	}
 
@@ -100,11 +104,11 @@ bool FreeDesktopPortalDesktop::read_setting(const char *p_namespace, const char
 	DBusMessage *reply = dbus_connection_send_with_reply_and_block(bus, message, 50, &error);
 	dbus_message_unref(message);
 	if (dbus_error_is_set(&error)) {
-		dbus_error_free(&error);
-		dbus_connection_unref(bus);
 		if (OS::get_singleton()->is_stdout_verbose()) {
-			ERR_PRINT(String() + "Error on D-Bus communication: " + error.message);
+			ERR_PRINT(vformat("Error on D-Bus communication: %s", error.message));
 		}
+		dbus_error_free(&error);
+		dbus_connection_unref(bus);
 		return false;
 	}
 
@@ -126,6 +130,317 @@ uint32_t FreeDesktopPortalDesktop::get_appearance_color_scheme() {
 	return value;
 }
 
+static const char *cs_empty = "";
+
+void FreeDesktopPortalDesktop::append_dbus_string(DBusMessageIter *p_iter, const String &p_string) {
+	CharString cs = p_string.utf8();
+	const char *cs_ptr = cs.ptr();
+	if (cs_ptr) {
+		dbus_message_iter_append_basic(p_iter, DBUS_TYPE_STRING, &cs_ptr);
+	} else {
+		dbus_message_iter_append_basic(p_iter, DBUS_TYPE_STRING, &cs_empty);
+	}
+}
+
+void FreeDesktopPortalDesktop::append_dbus_dict_filters(DBusMessageIter *p_iter, const Vector<String> &p_filters) {
+	DBusMessageIter dict_iter;
+	DBusMessageIter var_iter;
+	DBusMessageIter arr_iter;
+	const char *filters_key = "filters";
+
+	dbus_message_iter_open_container(p_iter, DBUS_TYPE_DICT_ENTRY, nullptr, &dict_iter);
+	dbus_message_iter_append_basic(&dict_iter, DBUS_TYPE_STRING, &filters_key);
+	dbus_message_iter_open_container(&dict_iter, DBUS_TYPE_VARIANT, "a(sa(us))", &var_iter);
+	dbus_message_iter_open_container(&var_iter, DBUS_TYPE_ARRAY, "(sa(us))", &arr_iter);
+	for (int i = 0; i < p_filters.size(); i++) {
+		Vector<String> tokens = p_filters[i].split(";");
+		if (tokens.size() == 2) {
+			DBusMessageIter struct_iter;
+			DBusMessageIter array_iter;
+			DBusMessageIter array_struct_iter;
+			dbus_message_iter_open_container(&arr_iter, DBUS_TYPE_STRUCT, nullptr, &struct_iter);
+			append_dbus_string(&struct_iter, tokens[0]);
+
+			dbus_message_iter_open_container(&struct_iter, DBUS_TYPE_ARRAY, "(us)", &array_iter);
+			dbus_message_iter_open_container(&array_iter, DBUS_TYPE_STRUCT, nullptr, &array_struct_iter);
+			{
+				const unsigned nil = 0;
+				dbus_message_iter_append_basic(&array_struct_iter, DBUS_TYPE_UINT32, &nil);
+			}
+			append_dbus_string(&array_struct_iter, tokens[1]);
+			dbus_message_iter_close_container(&array_iter, &array_struct_iter);
+			dbus_message_iter_close_container(&struct_iter, &array_iter);
+			dbus_message_iter_close_container(&arr_iter, &struct_iter);
+		}
+	}
+	dbus_message_iter_close_container(&var_iter, &arr_iter);
+	dbus_message_iter_close_container(&dict_iter, &var_iter);
+	dbus_message_iter_close_container(p_iter, &dict_iter);
+}
+
+void FreeDesktopPortalDesktop::append_dbus_dict_string(DBusMessageIter *p_iter, const String &p_key, const String &p_value, bool p_as_byte_array) {
+	DBusMessageIter dict_iter;
+	DBusMessageIter var_iter;
+	dbus_message_iter_open_container(p_iter, DBUS_TYPE_DICT_ENTRY, nullptr, &dict_iter);
+	append_dbus_string(&dict_iter, p_key);
+
+	if (p_as_byte_array) {
+		DBusMessageIter arr_iter;
+		dbus_message_iter_open_container(&dict_iter, DBUS_TYPE_VARIANT, "ay", &var_iter);
+		dbus_message_iter_open_container(&var_iter, DBUS_TYPE_ARRAY, "y", &arr_iter);
+		CharString cs = p_value.utf8();
+		const char *cs_ptr = cs.get_data();
+		do {
+			dbus_message_iter_append_basic(&arr_iter, DBUS_TYPE_BYTE, cs_ptr);
+		} while (*cs_ptr++);
+		dbus_message_iter_close_container(&var_iter, &arr_iter);
+	} else {
+		dbus_message_iter_open_container(&dict_iter, DBUS_TYPE_VARIANT, "s", &var_iter);
+		append_dbus_string(&var_iter, p_value);
+	}
+
+	dbus_message_iter_close_container(&dict_iter, &var_iter);
+	dbus_message_iter_close_container(p_iter, &dict_iter);
+}
+
+void FreeDesktopPortalDesktop::append_dbus_dict_bool(DBusMessageIter *p_iter, const String &p_key, bool p_value) {
+	DBusMessageIter dict_iter;
+	DBusMessageIter var_iter;
+	dbus_message_iter_open_container(p_iter, DBUS_TYPE_DICT_ENTRY, nullptr, &dict_iter);
+	append_dbus_string(&dict_iter, p_key);
+
+	dbus_message_iter_open_container(&dict_iter, DBUS_TYPE_VARIANT, "b", &var_iter);
+	{
+		int val = p_value;
+		dbus_message_iter_append_basic(&var_iter, DBUS_TYPE_BOOLEAN, &val);
+	}
+
+	dbus_message_iter_close_container(&dict_iter, &var_iter);
+	dbus_message_iter_close_container(p_iter, &dict_iter);
+}
+
+bool FreeDesktopPortalDesktop::file_chooser_parse_response(DBusMessageIter *p_iter, bool &r_cancel, Vector<String> &r_urls) {
+	ERR_FAIL_COND_V(dbus_message_iter_get_arg_type(p_iter) != DBUS_TYPE_UINT32, false);
+
+	dbus_uint32_t resp_code;
+	dbus_message_iter_get_basic(p_iter, &resp_code);
+	if (resp_code != 0) {
+		r_cancel = true;
+	} else {
+		r_cancel = false;
+		ERR_FAIL_COND_V(!dbus_message_iter_next(p_iter), false);
+		ERR_FAIL_COND_V(dbus_message_iter_get_arg_type(p_iter) != DBUS_TYPE_ARRAY, false);
+
+		DBusMessageIter dict_iter;
+		dbus_message_iter_recurse(p_iter, &dict_iter);
+		while (dbus_message_iter_get_arg_type(&dict_iter) == DBUS_TYPE_DICT_ENTRY) {
+			DBusMessageIter iter;
+			dbus_message_iter_recurse(&dict_iter, &iter);
+			if (dbus_message_iter_get_arg_type(&iter) == DBUS_TYPE_STRING) {
+				const char *key;
+				dbus_message_iter_get_basic(&iter, &key);
+				dbus_message_iter_next(&iter);
+
+				DBusMessageIter var_iter;
+				dbus_message_iter_recurse(&iter, &var_iter);
+				if (strcmp(key, "uris") == 0) {
+					if (dbus_message_iter_get_arg_type(&var_iter) == DBUS_TYPE_ARRAY) {
+						DBusMessageIter uri_iter;
+						dbus_message_iter_recurse(&var_iter, &uri_iter);
+						while (dbus_message_iter_get_arg_type(&uri_iter) == DBUS_TYPE_STRING) {
+							const char *value;
+							dbus_message_iter_get_basic(&uri_iter, &value);
+							r_urls.push_back(String::utf8(value).trim_prefix("file://").uri_decode());
+							if (!dbus_message_iter_next(&uri_iter)) {
+								break;
+							}
+						}
+					}
+				}
+			}
+			if (!dbus_message_iter_next(&dict_iter)) {
+				break;
+			}
+		}
+	}
+	return true;
+}
+
+Error FreeDesktopPortalDesktop::file_dialog_show(const String &p_xid, const String &p_title, const String &p_current_directory, const String &p_filename, DisplayServer::FileDialogMode p_mode, const Vector<String> &p_filters, const Callable &p_callback) {
+	if (unsupported) {
+		return FAILED;
+	}
+
+	DBusError err;
+	dbus_error_init(&err);
+
+	// Open connection and add signal handler.
+	FileDialogData fd;
+	fd.callback = p_callback;
+
+	CryptoCore::RandomGenerator rng;
+	ERR_FAIL_COND_V_MSG(rng.init(), FAILED, "Failed to initialize random number generator.");
+	uint8_t uuid[64];
+	Error rng_err = rng.get_random_bytes(uuid, 64);
+	ERR_FAIL_COND_V_MSG(rng_err, rng_err, "Failed to generate unique token.");
+
+	fd.connection = dbus_bus_get(DBUS_BUS_SESSION, &err);
+	if (dbus_error_is_set(&err)) {
+		ERR_PRINT(vformat("Failed to open DBus connection: %s", err.message));
+		dbus_error_free(&err);
+		unsupported = true;
+		return FAILED;
+	}
+
+	String dbus_unique_name = String::utf8(dbus_bus_get_unique_name(fd.connection));
+	String token = String::hex_encode_buffer(uuid, 64);
+	String path = vformat("/org/freedesktop/portal/desktop/request/%s/%s", dbus_unique_name.replace(".", "_").replace(":", ""), token);
+
+	fd.path = vformat("type='signal',sender='org.freedesktop.portal.Desktop',path='%s',interface='org.freedesktop.portal.Request',member='Response',destination='%s'", path, dbus_unique_name);
+	dbus_bus_add_match(fd.connection, fd.path.utf8().get_data(), &err);
+	if (dbus_error_is_set(&err)) {
+		ERR_PRINT(vformat("Failed to add DBus match: %s", err.message));
+		dbus_error_free(&err);
+		dbus_connection_unref(fd.connection);
+		return FAILED;
+	}
+
+	// Generate FileChooser message.
+	const char *method = nullptr;
+	switch (p_mode) {
+		case DisplayServer::FILE_DIALOG_MODE_SAVE_FILE: {
+			method = "SaveFile";
+		} break;
+		case DisplayServer::FILE_DIALOG_MODE_OPEN_ANY:
+		case DisplayServer::FILE_DIALOG_MODE_OPEN_FILE:
+		case DisplayServer::FILE_DIALOG_MODE_OPEN_DIR:
+		case DisplayServer::FILE_DIALOG_MODE_OPEN_FILES: {
+			method = "OpenFile";
+		} break;
+	}
+
+	DBusMessage *message = dbus_message_new_method_call(BUS_OBJECT_NAME, BUS_OBJECT_PATH, BUS_INTERFACE_FILE_CHOOSER, method);
+	{
+		DBusMessageIter iter;
+		dbus_message_iter_init_append(message, &iter);
+
+		append_dbus_string(&iter, p_xid);
+		append_dbus_string(&iter, p_title);
+
+		DBusMessageIter arr_iter;
+		dbus_message_iter_open_container(&iter, DBUS_TYPE_ARRAY, "{sv}", &arr_iter);
+
+		append_dbus_dict_string(&arr_iter, "handle_token", token);
+		append_dbus_dict_bool(&arr_iter, "multiple", p_mode == DisplayServer::FILE_DIALOG_MODE_OPEN_FILES);
+		append_dbus_dict_bool(&arr_iter, "directory", p_mode == DisplayServer::FILE_DIALOG_MODE_OPEN_DIR);
+		append_dbus_dict_filters(&arr_iter, p_filters);
+		append_dbus_dict_string(&arr_iter, "current_folder", p_current_directory, true);
+		if (p_mode == DisplayServer::FILE_DIALOG_MODE_SAVE_FILE) {
+			append_dbus_dict_string(&arr_iter, "current_name", p_filename);
+		}
+
+		dbus_message_iter_close_container(&iter, &arr_iter);
+	}
+
+	DBusMessage *reply = dbus_connection_send_with_reply_and_block(fd.connection, message, DBUS_TIMEOUT_INFINITE, &err);
+	dbus_message_unref(message);
+
+	if (!reply || dbus_error_is_set(&err)) {
+		ERR_PRINT(vformat("Failed to send DBus message: %s", err.message));
+		dbus_error_free(&err);
+		dbus_bus_remove_match(fd.connection, fd.path.utf8().get_data(), &err);
+		dbus_connection_unref(fd.connection);
+		return FAILED;
+	}
+
+	// Update signal path.
+	{
+		DBusMessageIter iter;
+		if (dbus_message_iter_init(reply, &iter)) {
+			if (dbus_message_iter_get_arg_type(&iter) == DBUS_TYPE_OBJECT_PATH) {
+				const char *new_path = nullptr;
+				dbus_message_iter_get_basic(&iter, &new_path);
+				if (String::utf8(new_path) != path) {
+					dbus_bus_remove_match(fd.connection, fd.path.utf8().get_data(), &err);
+					if (dbus_error_is_set(&err)) {
+						ERR_PRINT(vformat("Failed to remove DBus match: %s", err.message));
+						dbus_error_free(&err);
+						dbus_connection_unref(fd.connection);
+						return FAILED;
+					}
+					fd.path = String::utf8(new_path);
+					dbus_bus_add_match(fd.connection, fd.path.utf8().get_data(), &err);
+					if (dbus_error_is_set(&err)) {
+						ERR_PRINT(vformat("Failed to add DBus match: %s", err.message));
+						dbus_error_free(&err);
+						dbus_connection_unref(fd.connection);
+						return FAILED;
+					}
+				}
+			}
+		}
+	}
+	dbus_message_unref(reply);
+
+	MutexLock lock(file_dialog_mutex);
+	file_dialogs.push_back(fd);
+
+	return OK;
+}
+
+void FreeDesktopPortalDesktop::_thread_file_dialog_monitor(void *p_ud) {
+	FreeDesktopPortalDesktop *portal = (FreeDesktopPortalDesktop *)p_ud;
+
+	while (!portal->file_dialog_thread_abort.is_set()) {
+		{
+			MutexLock lock(portal->file_dialog_mutex);
+			for (int i = portal->file_dialogs.size() - 1; i >= 0; i--) {
+				bool remove = false;
+				{
+					FreeDesktopPortalDesktop::FileDialogData &fd = portal->file_dialogs.write[i];
+					if (fd.connection) {
+						while (true) {
+							DBusMessage *msg = dbus_connection_pop_message(fd.connection);
+							if (!msg) {
+								break;
+							} else if (dbus_message_is_signal(msg, "org.freedesktop.portal.Request", "Response")) {
+								DBusMessageIter iter;
+								if (dbus_message_iter_init(msg, &iter)) {
+									bool cancel = false;
+									Vector<String> uris;
+									file_chooser_parse_response(&iter, cancel, uris);
+
+									if (fd.callback.is_valid()) {
+										Variant v_status = !cancel;
+										Variant v_files = uris;
+										Variant *v_args[2] = { &v_status, &v_files };
+										fd.callback.call_deferredp((const Variant **)&v_args, 2);
+									}
+								}
+								dbus_message_unref(msg);
+
+								DBusError err;
+								dbus_error_init(&err);
+								dbus_bus_remove_match(fd.connection, fd.path.utf8().get_data(), &err);
+								dbus_error_free(&err);
+								dbus_connection_unref(fd.connection);
+								remove = true;
+								break;
+							}
+							dbus_message_unref(msg);
+						}
+						dbus_connection_read_write(fd.connection, 0);
+					}
+				}
+				if (remove) {
+					portal->file_dialogs.remove_at(i);
+				}
+			}
+		}
+		usleep(50000);
+	}
+}
+
 FreeDesktopPortalDesktop::FreeDesktopPortalDesktop() {
 #ifdef SOWRAP_ENABLED
 #ifdef DEBUG_ENABLED
@@ -153,6 +468,27 @@ FreeDesktopPortalDesktop::FreeDesktopPortalDesktop() {
 		print_verbose("PortalDesktop: Unsupported DBus library version!");
 		unsupported = true;
 	}
+
+	if (!unsupported) {
+		file_dialog_thread_abort.clear();
+		file_dialog_thread.start(FreeDesktopPortalDesktop::_thread_file_dialog_monitor, this);
+	}
+}
+
+FreeDesktopPortalDesktop::~FreeDesktopPortalDesktop() {
+	file_dialog_thread_abort.set();
+	if (file_dialog_thread.is_started()) {
+		file_dialog_thread.wait_to_finish();
+	}
+	for (FreeDesktopPortalDesktop::FileDialogData &fd : file_dialogs) {
+		if (fd.connection) {
+			DBusError err;
+			dbus_error_init(&err);
+			dbus_bus_remove_match(fd.connection, fd.path.utf8().get_data(), &err);
+			dbus_error_free(&err);
+			dbus_connection_unref(fd.connection);
+		}
+	}
 }
 
 #endif // DBUS_ENABLED

platform/linuxbsd/freedesktop_portal_desktop.h

@@ -33,20 +33,48 @@
 
 #ifdef DBUS_ENABLED
 
-#include <stdint.h>
+#include "core/os/thread.h"
+#include "servers/display_server.h"
+
+struct DBusMessage;
+struct DBusConnection;
+struct DBusMessageIter;
 
 class FreeDesktopPortalDesktop {
 private:
 	bool unsupported = false;
 
+	static bool try_parse_variant(DBusMessage *p_reply_message, int p_type, void *r_value);
 	// Read a setting from org.freekdesktop.portal.Settings
 	bool read_setting(const char *p_namespace, const char *p_key, int p_type, void *r_value);
 
+	static void append_dbus_string(DBusMessageIter *p_iter, const String &p_string);
+	static void append_dbus_dict_filters(DBusMessageIter *p_iter, const Vector<String> &p_filters);
+	static void append_dbus_dict_string(DBusMessageIter *p_iter, const String &p_key, const String &p_value, bool p_as_byte_array = false);
+	static void append_dbus_dict_bool(DBusMessageIter *p_iter, const String &p_key, bool p_value);
+	static bool file_chooser_parse_response(DBusMessageIter *p_iter, bool &r_cancel, Vector<String> &r_urls);
+
+	struct FileDialogData {
+		DBusConnection *connection = nullptr;
+		Callable callback;
+		String path;
+	};
+
+	Mutex file_dialog_mutex;
+	Vector<FileDialogData> file_dialogs;
+	Thread file_dialog_thread;
+	SafeFlag file_dialog_thread_abort;
+
+	static void _thread_file_dialog_monitor(void *p_ud);
+
 public:
 	FreeDesktopPortalDesktop();
+	~FreeDesktopPortalDesktop();
 
 	bool is_supported() { return !unsupported; }
 
+	Error file_dialog_show(const String &p_xid, const String &p_title, const String &p_current_directory, const String &p_filename, DisplayServer::FileDialogMode p_mode, const Vector<String> &p_filters, const Callable &p_callback);
+
 	// Retrieve the system's preferred color scheme.
 	// 0: No preference or unknown.
 	// 1: Prefer dark appearance.

platform/linuxbsd/joypad_linux.cpp

@@ -82,31 +82,9 @@ void JoypadLinux::Joypad::reset() {
 	events.clear();
 }
 
-#ifdef UDEV_ENABLED
-// This function is derived from SDL:
-// https://github.com/libsdl-org/SDL/blob/main/src/core/linux/SDL_sandbox.c#L28-L45
-static bool detect_sandbox() {
-	if (access("/.flatpak-info", F_OK) == 0) {
-		return true;
-	}
-
-	// For Snap, we check multiple variables because they might be set for
-	// unrelated reasons. This is the same thing WebKitGTK does.
-	if (OS::get_singleton()->has_environment("SNAP") && OS::get_singleton()->has_environment("SNAP_NAME") && OS::get_singleton()->has_environment("SNAP_REVISION")) {
-		return true;
-	}
-
-	if (access("/run/host/container-manager", F_OK) == 0) {
-		return true;
-	}
-
-	return false;
-}
-#endif // UDEV_ENABLED
-
 JoypadLinux::JoypadLinux(Input *in) {
 #ifdef UDEV_ENABLED
-	if (detect_sandbox()) {
+	if (OS::get_singleton()->is_sandboxed()) {
 		// Linux binaries in sandboxes / containers need special handling because
 		// libudev doesn't work there. So we need to fallback to manual parsing
 		// of /dev/input in such case.

platform/linuxbsd/os_linuxbsd.cpp

@@ -164,6 +164,27 @@ String OS_LinuxBSD::get_processor_name() const {
 	ERR_FAIL_V_MSG("", String("Couldn't get the CPU model name from `/proc/cpuinfo`. Returning an empty string."));
 }
 
+bool OS_LinuxBSD::is_sandboxed() const {
+	// This function is derived from SDL:
+	// https://github.com/libsdl-org/SDL/blob/main/src/core/linux/SDL_sandbox.c#L28-L45
+
+	if (access("/.flatpak-info", F_OK) == 0) {
+		return true;
+	}
+
+	// For Snap, we check multiple variables because they might be set for
+	// unrelated reasons. This is the same thing WebKitGTK does.
+	if (has_environment("SNAP") && has_environment("SNAP_NAME") && has_environment("SNAP_REVISION")) {
+		return true;
+	}
+
+	if (access("/run/host/container-manager", F_OK) == 0) {
+		return true;
+	}
+
+	return false;
+}
+
 void OS_LinuxBSD::finalize() {
 	if (main_loop) {
 		memdelete(main_loop);

platform/linuxbsd/os_linuxbsd.h

@@ -123,6 +123,8 @@ public:
 	virtual String get_unique_id() const override;
 	virtual String get_processor_name() const override;
 
+	virtual bool is_sandboxed() const override;
+
 	virtual void alert(const String &p_alert, const String &p_title = "ALERT!") override;
 
 	virtual bool _check_internal_feature_support(const String &p_feature) override;

platform/linuxbsd/x11/display_server_x11.cpp

@@ -122,6 +122,9 @@ bool DisplayServerX11::has_feature(Feature p_feature) const {
 		case FEATURE_WINDOW_TRANSPARENCY:
 		//case FEATURE_HIDPI:
 		case FEATURE_ICON:
+#ifdef DBUS_ENABLED
+		case FEATURE_NATIVE_DIALOG:
+#endif
 		//case FEATURE_NATIVE_ICON:
 		case FEATURE_SWAP_BUFFERS:
 #ifdef DBUS_ENABLED
@@ -360,6 +363,17 @@ bool DisplayServerX11::is_dark_mode() const {
 	}
 }
 
+Error DisplayServerX11::file_dialog_show(const String &p_title, const String &p_current_directory, const String &p_filename, bool p_show_hidden, FileDialogMode p_mode, const Vector<String> &p_filters, const Callable &p_callback) {
+	WindowID window_id = _get_focused_window_or_popup();
+
+	if (!windows.has(window_id)) {
+		window_id = MAIN_WINDOW_ID;
+	}
+
+	String xid = vformat("x11:%x", (uint64_t)windows[window_id].x11_window);
+	return portal_desktop->file_dialog_show(xid, p_title, p_current_directory, p_filename, p_mode, p_filters, p_callback);
+}
+
 #endif
 
 void DisplayServerX11::mouse_set_mode(MouseMode p_mode) {

platform/linuxbsd/x11/display_server_x11.h

@@ -393,6 +393,8 @@ public:
 #if defined(DBUS_ENABLED)
 	virtual bool is_dark_mode_supported() const override;
 	virtual bool is_dark_mode() const override;
+
+	virtual Error file_dialog_show(const String &p_title, const String &p_current_directory, const String &p_filename, bool p_show_hidden, FileDialogMode p_mode, const Vector<String> &p_filters, const Callable &p_callback) override;
 #endif
 
 	virtual void mouse_set_mode(MouseMode p_mode) override;