lib: Replace done channel with contexts in and add names to util services (#6166)

lib/model/folder.go

@@ -49,7 +49,6 @@ type folder struct {
 	fset    *db.FileSet
 	ignores *ignore.Matcher
 	ctx     context.Context
-	cancel  context.CancelFunc
 
 	scanInterval        time.Duration
 	scanTimer           *time.Timer
@@ -80,8 +79,6 @@ type puller interface {
 }
 
 func newFolder(model *model, fset *db.FileSet, ignores *ignore.Matcher, cfg config.FolderConfiguration, evLogger events.Logger) folder {
-	ctx, cancel := context.WithCancel(context.Background())
-
 	return folder{
 		stateTracker:              newStateTracker(cfg.ID, evLogger),
 		FolderConfiguration:       cfg,
@@ -91,8 +88,6 @@ func newFolder(model *model, fset *db.FileSet, ignores *ignore.Matcher, cfg conf
 		shortID: model.shortID,
 		fset:    fset,
 		ignores: ignores,
-		ctx:     ctx,
-		cancel:  cancel,
 
 		scanInterval:        time.Duration(cfg.RescanIntervalS) * time.Second,
 		scanTimer:           time.NewTimer(time.Millisecond), // The first scan should be done immediately.
@@ -109,10 +104,12 @@ func newFolder(model *model, fset *db.FileSet, ignores *ignore.Matcher, cfg conf
 	}
 }
 
-func (f *folder) serve(_ chan struct{}) {
+func (f *folder) serve(ctx context.Context) {
 	atomic.AddInt32(&f.model.foldersRunning, 1)
 	defer atomic.AddInt32(&f.model.foldersRunning, -1)
 
+	f.ctx = ctx
+
 	l.Debugln(f, "starting")
 	defer l.Debugln(f, "exiting")
 
@@ -256,11 +253,6 @@ func (f *folder) Delay(next time.Duration) {
 	f.scanDelay <- next
 }
 
-func (f *folder) Stop() {
-	f.cancel()
-	f.Service.Stop()
-}
-
 // CheckHealth checks the folder for common errors, updates the folder state
 // and returns the current folder error, or nil if the folder is healthy.
 func (f *folder) CheckHealth() error {
@@ -643,7 +635,7 @@ func (f *folder) monitorWatch(ctx context.Context) {
 				failTimer.Reset(time.Minute)
 				continue
 			}
-			watchaggregator.Aggregate(eventChan, f.watchChan, f.FolderConfiguration, f.model.cfg, f.evLogger, aggrCtx)
+			watchaggregator.Aggregate(aggrCtx, eventChan, f.watchChan, f.FolderConfiguration, f.model.cfg, f.evLogger)
 			l.Debugln("Started filesystem watcher for folder", f.Description())
 		case err = <-errChan:
 			f.setWatchError(err)

lib/model/folder_sendonly.go

@@ -30,7 +30,7 @@ func newSendOnlyFolder(model *model, fset *db.FileSet, ignores *ignore.Matcher,
 		folder: newFolder(model, fset, ignores, cfg, evLogger),
 	}
 	f.folder.puller = f
-	f.folder.Service = util.AsService(f.serve)
+	f.folder.Service = util.AsService(f.serve, f.String())
 	return f
 }
 

lib/model/folder_sendrecv.go

@@ -118,7 +118,7 @@ func newSendReceiveFolder(model *model, fset *db.FileSet, ignores *ignore.Matche
 		pullErrorsMut: sync.NewMutex(),
 	}
 	f.folder.puller = f
-	f.folder.Service = util.AsService(f.serve)
+	f.folder.Service = util.AsService(f.serve, f.String())
 
 	if f.Copiers == 0 {
 		f.Copiers = defaultCopiers

lib/model/folder_summary.go

@@ -7,6 +7,7 @@
 package model
 
 import (
+	"context"
 	"fmt"
 	"strings"
 	"time"
@@ -63,8 +64,8 @@ func NewFolderSummaryService(cfg config.Wrapper, m Model, id protocol.DeviceID,
 		lastEventReqMut: sync.NewMutex(),
 	}
 
-	service.Add(util.AsService(service.listenForUpdates))
-	service.Add(util.AsService(service.calculateSummaries))
+	service.Add(util.AsService(service.listenForUpdates, fmt.Sprintf("%s/listenForUpdates", service)))
+	service.Add(util.AsService(service.calculateSummaries, fmt.Sprintf("%s/calculateSummaries", service)))
 
 	return service
 }
@@ -145,7 +146,7 @@ func (c *folderSummaryService) OnEventRequest() {
 
 // listenForUpdates subscribes to the event bus and makes note of folders that
 // need their data recalculated.
-func (c *folderSummaryService) listenForUpdates(stop chan struct{}) {
+func (c *folderSummaryService) listenForUpdates(ctx context.Context) {
 	sub := c.evLogger.Subscribe(events.LocalIndexUpdated | events.RemoteIndexUpdated | events.StateChanged | events.RemoteDownloadProgress | events.DeviceConnected | events.FolderWatchStateChanged | events.DownloadProgress)
 	defer sub.Unsubscribe()
 
@@ -155,7 +156,7 @@ func (c *folderSummaryService) listenForUpdates(stop chan struct{}) {
 		select {
 		case ev := <-sub.C():
 			c.processUpdate(ev)
-		case <-stop:
+		case <-ctx.Done():
 			return
 		}
 	}
@@ -234,7 +235,7 @@ func (c *folderSummaryService) processUpdate(ev events.Event) {
 
 // calculateSummaries periodically recalculates folder summaries and
 // completion percentage, and sends the results on the event bus.
-func (c *folderSummaryService) calculateSummaries(stop chan struct{}) {
+func (c *folderSummaryService) calculateSummaries(ctx context.Context) {
 	const pumpInterval = 2 * time.Second
 	pump := time.NewTimer(pumpInterval)
 
@@ -255,7 +256,7 @@ func (c *folderSummaryService) calculateSummaries(stop chan struct{}) {
 		case folder := <-c.immediate:
 			c.sendSummary(folder)
 
-		case <-stop:
+		case <-ctx.Done():
 			return
 		}
 	}

lib/model/model.go

@@ -1227,7 +1227,7 @@ func (m *model) ClusterConfig(deviceID protocol.DeviceID, cm protocol.ClusterCon
 			dropSymlinks: dropSymlinks,
 			evLogger:     m.evLogger,
 		}
-		is.Service = util.AsService(is.serve)
+		is.Service = util.AsService(is.serve, is.String())
 		// The token isn't tracked as the service stops when the connection
 		// terminates and is automatically removed from supervisor (by
 		// implementing suture.IsCompletable).
@@ -1970,7 +1970,7 @@ type indexSender struct {
 	connClosed   chan struct{}
 }
 
-func (s *indexSender) serve(stop chan struct{}) {
+func (s *indexSender) serve(ctx context.Context) {
 	var err error
 
 	l.Debugf("Starting indexSender for %s to %s at %s (slv=%d)", s.folder, s.dev, s.conn, s.prevSequence)
@@ -1991,7 +1991,7 @@ func (s *indexSender) serve(stop chan struct{}) {
 
 	for err == nil {
 		select {
-		case <-stop:
+		case <-ctx.Done():
 			return
 		case <-s.connClosed:
 			return
@@ -2004,7 +2004,7 @@ func (s *indexSender) serve(stop chan struct{}) {
 		// sending for.
 		if s.fset.Sequence(protocol.LocalDeviceID) <= s.prevSequence {
 			select {
-			case <-stop:
+			case <-ctx.Done():
 				return
 			case <-s.connClosed:
 				return
@@ -2037,7 +2037,7 @@ func (s *indexSender) sendIndexTo() error {
 	initial := s.prevSequence == 0
 	batch := newFileInfoBatch(nil)
 	batch.flushFn = func(fs []protocol.FileInfo) error {
-		l.Debugf("Sending indexes for %s to %s at %s: %d files (<%d bytes)", s.folder, s.dev, s.conn, len(batch.infos), batch.size)
+		l.Debugf("%v: Sending %d files (<%d bytes)", s, len(batch.infos), batch.size)
 		if initial {
 			initial = false
 			return s.conn.Index(s.folder, fs)
@@ -2099,6 +2099,10 @@ func (s *indexSender) sendIndexTo() error {
 	return err
 }
 
+func (s *indexSender) String() string {
+	return fmt.Sprintf("indexSender@%p for %s to %s at %s", s, s.folder, s.dev, s.conn)
+}
+
 func (m *model) requestGlobal(ctx context.Context, deviceID protocol.DeviceID, folder, name string, offset int64, size int, hash []byte, weakHash uint32, fromTemporary bool) ([]byte, error) {
 	m.pmut.RLock()
 	nc, ok := m.conn[deviceID]

lib/model/progressemitter.go

@@ -7,6 +7,7 @@
 package model
 
 import (
+	"context"
 	"fmt"
 	"time"
 
@@ -47,7 +48,7 @@ func NewProgressEmitter(cfg config.Wrapper, evLogger events.Logger) *ProgressEmi
 		evLogger:           evLogger,
 		mut:                sync.NewMutex(),
 	}
-	t.Service = util.AsService(t.serve)
+	t.Service = util.AsService(t.serve, t.String())
 
 	t.CommitConfiguration(config.Configuration{}, cfg.RawCopy())
 	cfg.Subscribe(t)
@@ -57,12 +58,12 @@ func NewProgressEmitter(cfg config.Wrapper, evLogger events.Logger) *ProgressEmi
 
 // serve starts the progress emitter which starts emitting DownloadProgress
 // events as the progress happens.
-func (t *ProgressEmitter) serve(stop chan struct{}) {
+func (t *ProgressEmitter) serve(ctx context.Context) {
 	var lastUpdate time.Time
 	var lastCount, newCount int
 	for {
 		select {
-		case <-stop:
+		case <-ctx.Done():
 			l.Debugln("progress emitter: stopping")
 			return
 		case <-t.timer.C: