-Add visible IO errors when closing a file fails due to it being locked (most likely on windows), closes #4760

core/os/file_access.cpp

@@ -35,6 +35,8 @@
 
 FileAccess::CreateFunc FileAccess::create_func[ACCESS_MAX]={0,0};
 
+FileAccess::FileCloseFailNotify FileAccess::close_fail_notify=NULL;
+
 
 bool FileAccess::backup_save=false;
 

core/os/file_access.h

@@ -47,6 +47,8 @@ public:
 		ACCESS_MAX
 	};
 
+	typedef void (*FileCloseFailNotify)(const String&);
+
 	typedef FileAccess*(*CreateFunc)();
 	bool endian_swap;
 	bool real_is_double;
@@ -56,7 +58,7 @@ protected:
 	virtual Error _open(const String& p_path, int p_mode_flags)=0; ///< open a file
 	virtual uint64_t _get_modified_time(const String& p_file)=0;
 
-
+	static FileCloseFailNotify close_fail_notify;
 private:
 
 	static bool backup_save;
@@ -69,8 +71,12 @@ private:
 		return memnew( T );
 	}
 
+
+
 public:
 
+	static void set_file_close_fail_notify_callback(FileCloseFailNotify p_cbk) { close_fail_notify=p_cbk; }
+
 	virtual void _set_access_type(AccessType p_access);
 
 	enum ModeFlags  {

drivers/unix/file_access_unix.cpp

@@ -124,6 +124,11 @@ void FileAccessUnix::close() {
 		//unlink(save_path.utf8().get_data());
 		//print_line("renaming..");
 		int rename_error = rename((save_path+".tmp").utf8().get_data(),save_path.utf8().get_data());
+
+		if (rename_error && close_fail_notify) {
+			close_fail_notify(save_path);
+		}
+
 		save_path="";
 		ERR_FAIL_COND( rename_error != 0);
 	}

drivers/windows/file_access_windows.cpp

@@ -131,6 +131,10 @@ void FileAccessWindows::close() {
 			//atomic replace for existing file
 			rename_error = !ReplaceFileW(save_path.c_str(), (save_path+".tmp").c_str(), NULL, 2|4, NULL, NULL);
 		}
+		if (rename_error && close_fail_notify) {
+			close_fail_notify(save_path);
+		}
+
 		save_path="";
 		ERR_FAIL_COND( rename_error );
 	}

tools/editor/editor_node.cpp

@@ -217,7 +217,7 @@ void EditorNode::_notification(int p_what) {
 	if (p_what==NOTIFICATION_EXIT_TREE) {
 
 		editor_data.save_editor_external_data();
-
+		FileAccess::set_file_close_fail_notify_callback(NULL);
 		log->deinit(); // do not get messages anymore
 	}
 	if (p_what==NOTIFICATION_PROCESS) {
@@ -5138,6 +5138,10 @@ void EditorNode::_dropped_files(const Vector<String>& p_files,int p_screen) {
 		EditorImportExport::get_singleton()->get_import_plugin(i)->import_from_drop(p_files,cur_path);
 	}
 }
+void EditorNode::_file_access_close_error_notify(const String& p_str) {
+
+	add_io_error("Unable to write to file '"+p_str+"', file in use, locked or lacking permissions.");
+}
 
 void EditorNode::_bind_methods() {
 
@@ -5233,7 +5237,6 @@ EditorNode::EditorNode() {
 	SceneState::set_disable_placeholders(true);
 	editor_initialize_certificates(); //for asset sharing
 
-
 	InputDefault *id = Input::get_singleton()->cast_to<InputDefault>();
 
 	if (id) {
@@ -6575,6 +6578,7 @@ EditorNode::EditorNode() {
 
 	_load_docks();
 
+	FileAccess::set_file_close_fail_notify_callback(_file_access_close_error_notify);
 
 
 }
@@ -6582,6 +6586,7 @@ EditorNode::EditorNode() {
 
 EditorNode::~EditorNode() {
 
+
 	memdelete( EditorHelp::get_doc_data() );
 	memdelete(editor_selection);
 	memdelete(editor_plugins_over);

tools/editor/editor_node.h

@@ -574,6 +574,7 @@ private:
 
 	void _update_addon_config();
 
+	static void _file_access_close_error_notify(const String& p_str);
 
 protected:
 	void _notification(int p_what);