fix more memory leaks

errors.go

@@ -60,7 +60,9 @@ func getRunningTaskError(err error) error {
 func getOLEErrorCode(err error) (uint32, error) {
 	if oleErr, ok1 := err.(*ole.OleError); ok1 {
 		if excepInfo, ok2 := oleErr.SubError().(ole.EXCEPINFO); ok2 {
-			return excepInfo.SCODE(), nil
+			code := excepInfo.SCODE()
+			excepInfo.Clear()
+			return code, nil
 		} else {
 			return uint32(oleErr.Code()), errors.New("failed to extract OLE sub-error code")
 		}

fill.go

@@ -258,9 +258,13 @@ func fillTrigger(triggersObj *ole.IDispatch, trigger Trigger) error {
 		defer valueQueriesObj.Release()
 
 		for name, value := range t.ValueQueries {
-			if _, err := oleutil.CallMethod(valueQueriesObj, "Create", name, value); err != nil {
+			res, err := oleutil.CallMethod(valueQueriesObj, "Create", name, value)
+			if err != nil {
 				return fmt.Errorf("error creating value %s: %w", name, getTaskSchedulerError(err))
 			}
+			if pairObj := res.ToIDispatch(); pairObj != nil {
+				pairObj.Release()
+			}
 		}
 	case IdleTrigger:
 		idleTriggerObj := h.query(triggerObj, ole.NewGUID("{d537d2b0-9fb3-4d34-9739-1ff5ce7b1ef3}"))

manage.go

@@ -195,6 +195,7 @@ func (t *TaskService) GetRunningTasks() (RunningTaskCollection, error) {
 		return nil
 	})
 	if err != nil {
+		runningTasks.Release()
 		return nil, err
 	}
 
@@ -208,6 +209,13 @@ func (t *TaskService) GetRegisteredTasks() (RegisteredTaskCollection, error) {
 		registeredTasks RegisteredTaskCollection
 	)
 
+	success := false
+	defer func() {
+		if !success {
+			registeredTasks.Release()
+		}
+	}()
+
 	// get tasks from root folder
 	res, err := oleutil.CallMethod(t.rootFolderObj, "GetTasks", int(TASK_ENUM_HIDDEN))
 	if err != nil {
@@ -285,6 +293,7 @@ func (t *TaskService) GetRegisteredTasks() (RegisteredTaskCollection, error) {
 		return nil, err
 	}
 
+	success = true
 	return registeredTasks, nil
 }
 
@@ -348,6 +357,7 @@ func (t TaskService) GetTasksInFolder(path string) (RegisteredTaskCollection, er
 		return nil
 	})
 	if err != nil {
+		registeredTasks.Release()
 		return nil, err
 	}
 
@@ -388,6 +398,13 @@ func (t TaskService) GetTaskFolder(path string) (TaskFolder, error) {
 	topFolderTaskCollection := res.ToIDispatch()
 	defer topFolderTaskCollection.Release()
 	topFolder := TaskFolder{Path: `\`}
+
+	success := false
+	defer func() {
+		if !success {
+			topFolder.Release()
+		}
+	}()
 	err = oleutil.ForEach(topFolderTaskCollection, func(v *ole.VARIANT) error {
 		task := v.ToIDispatch()
 
@@ -476,6 +493,7 @@ func (t TaskService) GetTaskFolder(path string) (TaskFolder, error) {
 		return TaskFolder{}, err
 	}
 
+	success = true
 	return topFolder, nil
 }
 
@@ -778,19 +796,25 @@ func (t *TaskService) DeleteTask(path string) error {
 }
 
 func (t *TaskService) registeredTaskExist(path string) bool {
-	_, err := oleutil.CallMethod(t.rootFolderObj, "GetTask", path)
+	res, err := oleutil.CallMethod(t.rootFolderObj, "GetTask", path)
 	if err != nil {
 		return false
 	}
+	if taskObj := res.ToIDispatch(); taskObj != nil {
+		taskObj.Release()
+	}
 
 	return true
 }
 
 func (t *TaskService) taskFolderExist(path string) bool {
-	_, err := oleutil.CallMethod(t.taskServiceObj, "GetFolder", path)
+	res, err := oleutil.CallMethod(t.taskServiceObj, "GetFolder", path)
 	if err != nil {
 		return false
 	}
+	if folderObj := res.ToIDispatch(); folderObj != nil {
+		folderObj.Release()
+	}
 
 	return true
 }

parse.go

@@ -13,33 +13,43 @@ import (
 	"github.com/go-ole/go-ole/oleutil"
 )
 
-func parseRunningTask(task *ole.IDispatch) (RunningTask, error) {
-	var err error
+func parseRunningTask(task *ole.IDispatch) (_ RunningTask, err error) {
+	defer func() {
+		if err != nil && task != nil {
+			task.Release()
+		}
+	}()
 
 	currentAction, err := oleutil.GetProperty(task, "CurrentAction")
 	if err != nil {
 		return RunningTask{}, getRunningTaskError(err)
 	}
+	defer currentAction.Clear()
 	enginePID, err := oleutil.GetProperty(task, "EnginePid")
 	if err != nil {
 		return RunningTask{}, getRunningTaskError(err)
 	}
+	defer enginePID.Clear()
 	instanceGUID, err := oleutil.GetProperty(task, "InstanceGuid")
 	if err != nil {
 		return RunningTask{}, getRunningTaskError(err)
 	}
+	defer instanceGUID.Clear()
 	name, err := oleutil.GetProperty(task, "Name")
 	if err != nil {
 		return RunningTask{}, getRunningTaskError(err)
 	}
+	defer name.Clear()
 	path, err := oleutil.GetProperty(task, "Path")
 	if err != nil {
 		return RunningTask{}, getRunningTaskError(err)
 	}
+	defer path.Clear()
 	state, err := oleutil.GetProperty(task, "State")
 	if err != nil {
 		return RunningTask{}, getRunningTaskError(err)
 	}
+	defer state.Clear()
 
 	runningTask := RunningTask{
 		taskObj:       task,
@@ -55,6 +65,13 @@ func parseRunningTask(task *ole.IDispatch) (RunningTask, error) {
 }
 
 func parseRegisteredTask(task *ole.IDispatch) (RegisteredTask, string, error) {
+	success := false
+	defer func() {
+		if !success && task != nil {
+			task.Release()
+		}
+	}()
+
 	h := &oleHelper{}
 
 	name := h.getString(task, "Name")
@@ -185,6 +202,8 @@ func parseRegisteredTask(task *ole.IDispatch) (RegisteredTask, string, error) {
 		LastTaskResult: lastTaskResult,
 	}
 
+	// Ownership of task now belongs to registeredTask; don't release it.
+	success = true
 	return registeredTask, path, nil
 }