X-Git-Url: https://git.giacomolli.uk/onechat/blobdiff_plain/baf7a940be8927278e3b4b87e7366cebfc16532f..80e348724041a694002fc38f57e8868b9b9a2be9:/syncer.go?ds=inline

diff --git a/syncer.go b/syncer.go
index 1549461..0784393 100644
--- a/syncer.go
+++ b/syncer.go
@@ -10,22 +10,6 @@ import (
 	"golang.org/x/sys/unix"
 )
 
-// openSyncer returns the syncer of the file system that holds dir. It syncs
-// with syncfs, which writes back only that file system.
-func openSyncer(dir string) (*Syncer, error) {
-	file, err := os.Open(dir)
-	if err != nil {
-		return nil, fmt.Errorf("open chat directory: %w", err)
-	}
-
-	s := newSyncer(func() error {
-		return unix.Syncfs(int(file.Fd()))
-	})
-	s.file = file
-
-	return s, nil
-}
-
 // Syncer makes the writes of a chat durable by group commit. Each write goes to
 // the operating system at once, so a crash of the process loses nothing. After
 // each write, Written starts a background sync of the file system of the chat,
@@ -48,6 +32,30 @@ type Syncer struct {
 	workers sync.WaitGroup
 }
 
+// openSyncer returns the syncer of the file system that holds dir. It syncs
+// with syncfs, which writes back only that file system.
+func openSyncer(dir string) (*Syncer, error) {
+	file, err := os.Open(dir)
+	if err != nil {
+		return nil, fmt.Errorf("open chat directory: %w", err)
+	}
+
+	s := newSyncer(func() error {
+		return unix.Syncfs(int(file.Fd()))
+	})
+	s.file = file
+
+	return s, nil
+}
+
+// newSyncer returns a syncer that makes the writes durable with sync.
+func newSyncer(sync func() error) *Syncer {
+	return &Syncer{
+		sync: sync,
+		done: make(chan struct{}),
+	}
+}
+
 // Written tells the syncer that a write went to the operating system, and
 // starts a sync when none runs.
 func (s *Syncer) Written() {
@@ -61,11 +69,13 @@ func (s *Syncer) Written() {
 // Flush returns when every write before the call is durable.
 func (s *Syncer) Flush(ctx context.Context) error {
 	s.mutex.Lock()
+
 	target := s.written
 	s.mutex.Unlock()
 
 	for {
 		s.mutex.Lock()
+
 		reached := s.durable >= target
 		failure := s.failure
 		done := s.done
@@ -92,6 +102,7 @@ func (s *Syncer) Flush(ctx context.Context) error {
 func (s *Syncer) Close() error {
 	err := s.Flush(context.Background())
 	s.workers.Wait()
+
 	if s.file != nil {
 		err = errors.Join(err, s.file.Close())
 		s.file = nil
@@ -109,6 +120,7 @@ func (s *Syncer) start() {
 
 	s.running = true
 	s.workers.Add(1)
+
 	go s.run(s.written)
 }
 
@@ -130,14 +142,7 @@ func (s *Syncer) run(target uint64) {
 	}
 
 	close(s.done)
+
 	s.done = make(chan struct{})
 	s.start()
 }
-
-// newSyncer returns a syncer that makes the writes durable with sync.
-func newSyncer(sync func() error) *Syncer {
-	return &Syncer{
-		sync: sync,
-		done: make(chan struct{}),
-	}
-}