cache: use atexit for cleanup

backend/cache/cache.go

@@ -23,6 +23,7 @@ import (
 	"github.com/ncw/rclone/fs/config/obscure"
 	"github.com/ncw/rclone/fs/hash"
 	"github.com/ncw/rclone/fs/walk"
+	"github.com/ncw/rclone/lib/atexit"
 	"github.com/pkg/errors"
 	"golang.org/x/net/context"
 	"golang.org/x/time/rate"
@@ -325,14 +326,14 @@ func NewFs(name, rootPath string) (fs.Fs, error) {
 	}
 	// Trap SIGINT and SIGTERM to close the DB handle gracefully
 	c := make(chan os.Signal, 1)
-	signal.Notify(c, syscall.SIGINT, syscall.SIGTERM, syscall.SIGHUP)
+	signal.Notify(c, syscall.SIGHUP)
+	atexit.Register(func() {
+		f.StopBackgroundRunners()
+	})
 	go func() {
 		for {
 			s := <-c
-			if s == syscall.SIGINT || s == syscall.SIGTERM {
-				fs.Debugf(f, "Got signal: %v", s)
-				f.StopBackgroundRunners()
-			} else if s == syscall.SIGHUP {
+			if s == syscall.SIGHUP {
 				fs.Infof(f, "Clearing cache from signal")
 				f.DirCacheFlush()
 			}
@@ -1245,7 +1246,7 @@ func (f *Fs) CleanUpCache(ignoreLastTs bool) {
 // can be triggered from a terminate signal or from testing between runs
 func (f *Fs) StopBackgroundRunners() {
 	f.cleanupChan <- false
-	if f.tempWritePath != "" {
+	if f.tempWritePath != "" && f.backgroundRunner != nil && f.backgroundRunner.isRunning() {
 		f.backgroundRunner.close()
 	}
 	f.cache.Close()

backend/cache/handle.go

@@ -561,6 +561,7 @@ type backgroundWriter struct {
 	stateCh  chan int
 	running  bool
 	notifyCh chan BackgroundUploadState
+	mu       sync.Mutex
 }
 
 func newBackgroundWriter(f *Fs) *backgroundWriter {
@@ -575,6 +576,10 @@ func newBackgroundWriter(f *Fs) *backgroundWriter {
 
 func (b *backgroundWriter) close() {
 	b.stateCh <- 2
+	b.mu.Lock()
+	defer b.mu.Unlock()
+	b.running = false
+
 }
 
 func (b *backgroundWriter) pause() {
@@ -585,6 +590,12 @@ func (b *backgroundWriter) play() {
 	b.stateCh <- 0
 }
 
+func (b *backgroundWriter) isRunning() bool {
+	b.mu.Lock()
+	defer b.mu.Unlock()
+	return b.running
+}
+
 func (b *backgroundWriter) notify(remote string, status int, err error) {
 	state := BackgroundUploadState{
 		Remote: remote,
@@ -601,7 +612,9 @@ func (b *backgroundWriter) notify(remote string, status int, err error) {
 func (b *backgroundWriter) run() {
 	state := 0
 	for {
+		b.mu.Lock()
 		b.running = true
+		b.mu.Unlock()
 		select {
 		case s := <-b.stateCh:
 			state = s
@@ -614,7 +627,6 @@ func (b *backgroundWriter) run() {
 			time.Sleep(time.Millisecond * 500)
 			continue
 		case 2:
-			b.running = false
 			return
 		}