PAUSED: Use git resume to continue working.

internal/backend/sftp/config.go

@@ -17,12 +17,14 @@ type Config struct {
 	Command string `option:"command" help:"specify command to create sftp connection"`
 
 	Connections uint `option:"connections" help:"set a limit for the number of concurrent connections (default: 5)"`
+  MaxReconnects uint `option:"max-reconnects" help:"set a limit for the number of reconnects when the connection is dropped (default: 0)"`
 }
 
 // NewConfig returns a new config with default options applied.
 func NewConfig() Config {
 	return Config{
 		Connections: 5,
+    MaxReconnects: 0
 	}
 }
 

internal/backend/sftp/sftp.go

@@ -30,6 +30,8 @@ type SFTP struct {
 	Config
 	*Connection
 	backend.Modes
+  mutex sync.Mutex
+  reconnectsLeft uint
 }
 
 var _ restic.Backend = &SFTP{}
@@ -46,11 +48,21 @@ func startClient(cfg Config) (*SFTP, error) {
 
 func (r *SFTP) reconnect() error {
 	debug.Log("RECONNECT")
+  r.mutex.Lock()
+  defer r.mutex.Unlock()
+	debug.Log("after mutext")
+
+  r.reconnectsLeft--
+
+  if r.reconnectsLeft < 0 {
+	debug.Log("LIMIT REACHED!!!!")
+    err := errors.Wrapf(r.Connection.clientError(), "max reconnections limit reached")
+    return backoff.Permanent(err)
+  }
 	if r.isClosing {
 		return nil
 	}
 
-	// TODO(ibash) make this thread safe
 	// TODO(ibash) error handling here...?
 	r.Connection.Close()
 	connection, err := NewConnection(r.Config)
@@ -60,7 +72,6 @@ func (r *SFTP) reconnect() error {
 	}
 
 	r.Connection = connection
-	// TODO(ibash) if already connected, clear out the old connection
 	return nil
 }