mv internal lib

lib/model/folderstate.go

@@ -0,0 +1,135 @@
+// Copyright (C) 2015 The Syncthing Authors.
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this file,
+// You can obtain one at http://mozilla.org/MPL/2.0/.
+
+package model
+
+import (
+	"time"
+
+	"github.com/syncthing/syncthing/lib/events"
+	"github.com/syncthing/syncthing/lib/sync"
+)
+
+type folderState int
+
+const (
+	FolderIdle folderState = iota
+	FolderScanning
+	FolderSyncing
+	FolderError
+)
+
+func (s folderState) String() string {
+	switch s {
+	case FolderIdle:
+		return "idle"
+	case FolderScanning:
+		return "scanning"
+	case FolderSyncing:
+		return "syncing"
+	case FolderError:
+		return "error"
+	default:
+		return "unknown"
+	}
+}
+
+type stateTracker struct {
+	folder string
+
+	mut     sync.Mutex
+	current folderState
+	err     error
+	changed time.Time
+}
+
+// setState sets the new folder state, for states other than FolderError.
+func (s *stateTracker) setState(newState folderState) {
+	if newState == FolderError {
+		panic("must use setError")
+	}
+
+	s.mut.Lock()
+	if newState != s.current {
+		/* This should hold later...
+		if s.current != FolderIdle && (newState == FolderScanning || newState == FolderSyncing) {
+			panic("illegal state transition " + s.current.String() + " -> " + newState.String())
+		}
+		*/
+
+		eventData := map[string]interface{}{
+			"folder": s.folder,
+			"to":     newState.String(),
+			"from":   s.current.String(),
+		}
+
+		if !s.changed.IsZero() {
+			eventData["duration"] = time.Since(s.changed).Seconds()
+		}
+
+		s.current = newState
+		s.changed = time.Now()
+
+		events.Default.Log(events.StateChanged, eventData)
+	}
+	s.mut.Unlock()
+}
+
+// getState returns the current state, the time when it last changed, and the
+// current error or nil.
+func (s *stateTracker) getState() (current folderState, changed time.Time, err error) {
+	s.mut.Lock()
+	current, changed, err = s.current, s.changed, s.err
+	s.mut.Unlock()
+	return
+}
+
+// setError sets the folder state to FolderError with the specified error.
+func (s *stateTracker) setError(err error) {
+	s.mut.Lock()
+	if s.current != FolderError || s.err.Error() != err.Error() {
+		eventData := map[string]interface{}{
+			"folder": s.folder,
+			"to":     FolderError.String(),
+			"from":   s.current.String(),
+			"error":  err.Error(),
+		}
+
+		if !s.changed.IsZero() {
+			eventData["duration"] = time.Since(s.changed).Seconds()
+		}
+
+		s.current = FolderError
+		s.err = err
+		s.changed = time.Now()
+
+		events.Default.Log(events.StateChanged, eventData)
+	}
+	s.mut.Unlock()
+}
+
+// clearError sets the folder state to FolderIdle and clears the error
+func (s *stateTracker) clearError() {
+	s.mut.Lock()
+	if s.current == FolderError {
+		eventData := map[string]interface{}{
+			"folder": s.folder,
+			"to":     FolderIdle.String(),
+			"from":   s.current.String(),
+		}
+
+		if !s.changed.IsZero() {
+			eventData["duration"] = time.Since(s.changed).Seconds()
+		}
+
+		s.current = FolderIdle
+		s.err = nil
+		s.changed = time.Now()
+
+		events.Default.Log(events.StateChanged, eventData)
+	}
+	s.mut.Unlock()
+}