lib: More contextification (#6343)

lib/model/bytesemaphore.go

@@ -7,6 +7,7 @@
 package model
 
 import (
+	"context"
 	"sync"
 )
 
@@ -29,19 +30,45 @@ func newByteSemaphore(max int) *byteSemaphore {
 	return &s
 }
 
+func (s *byteSemaphore) takeWithContext(ctx context.Context, bytes int) error {
+	done := make(chan struct{})
+	var err error
+	go func() {
+		err = s.takeInner(ctx, bytes)
+		close(done)
+	}()
+	select {
+	case <-done:
+	case <-ctx.Done():
+		s.cond.Broadcast()
+		<-done
+	}
+	return err
+}
+
 func (s *byteSemaphore) take(bytes int) {
+	_ = s.takeInner(context.Background(), bytes)
+}
+
+func (s *byteSemaphore) takeInner(ctx context.Context, bytes int) error {
 	s.mut.Lock()
+	defer s.mut.Unlock()
 	if bytes > s.max {
 		bytes = s.max
 	}
 	for bytes > s.available {
 		s.cond.Wait()
+		select {
+		case <-ctx.Done():
+			return ctx.Err()
+		default:
+		}
 		if bytes > s.max {
 			bytes = s.max
 		}
 	}
 	s.available -= bytes
-	s.mut.Unlock()
+	return nil
 }
 
 func (s *byteSemaphore) give(bytes int) {

lib/model/folder.go

@@ -301,7 +301,9 @@ func (f *folder) pull() bool {
 	f.setState(FolderSyncWaiting)
 	defer f.setState(FolderIdle)
 
-	f.ioLimiter.take(1)
+	if err := f.ioLimiter.takeWithContext(f.ctx, 1); err != nil {
+		return true
+	}
 	defer f.ioLimiter.give(1)
 
 	return f.puller.pull()
@@ -340,7 +342,9 @@ func (f *folder) scanSubdirs(subDirs []string) error {
 	f.setError(nil)
 	f.setState(FolderScanWaiting)
 
-	f.ioLimiter.take(1)
+	if err := f.ioLimiter.takeWithContext(f.ctx, 1); err != nil {
+		return err
+	}
 	defer f.ioLimiter.give(1)
 
 	for i := range subDirs {

lib/model/folder_sendrecv.go

@@ -1392,7 +1392,10 @@ func (f *sendReceiveFolder) pullerRoutine(in <-chan pullBlockState, out chan<- *
 		state := state
 		bytes := int(state.block.Size)
 
-		requestLimiter.take(bytes)
+		if err := requestLimiter.takeWithContext(f.ctx, bytes); err != nil {
+			break
+		}
+
 		wg.Add(1)
 
 		go func() {

lib/model/model_test.go

@@ -3211,6 +3211,9 @@ func TestParentOfUnignored(t *testing.T) {
 // restarts would leave more than one folder runner alive.
 func TestFolderRestartZombies(t *testing.T) {
 	wrapper := createTmpWrapper(defaultCfg.Copy())
+	opts := wrapper.Options()
+	opts.RawMaxFolderConcurrency = -1
+	wrapper.SetOptions(opts)
 	folderCfg, _ := wrapper.Folder("default")
 	folderCfg.FilesystemType = fs.FilesystemTypeFake
 	wrapper.SetFolder(folderCfg)