core/rawdb, node: use standalone flock dependency (#26633)

node/node.go

@@ -37,7 +37,7 @@ import (
 	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/p2p"
 	"github.com/ethereum/go-ethereum/rpc"
-	"github.com/prometheus/tsdb/fileutil"
+	"github.com/gofrs/flock"
 )
 
 // Node is a container on which services can be registered.
@@ -46,13 +46,13 @@ type Node struct {
 	config        *Config
 	accman        *accounts.Manager
 	log           log.Logger
-	keyDir        string            // key store directory
-	keyDirTemp    bool              // If true, key directory will be removed by Stop
-	dirLock       fileutil.Releaser // prevents concurrent use of instance directory
-	stop          chan struct{}     // Channel to wait for termination notifications
-	server        *p2p.Server       // Currently running P2P networking layer
-	startStopLock sync.Mutex        // Start/Stop are protected by an additional lock
-	state         int               // Tracks state of node lifecycle
+	keyDir        string        // key store directory
+	keyDirTemp    bool          // If true, key directory will be removed by Stop
+	dirLock       *flock.Flock  // prevents concurrent use of instance directory
+	stop          chan struct{} // Channel to wait for termination notifications
+	server        *p2p.Server   // Currently running P2P networking layer
+	startStopLock sync.Mutex    // Start/Stop are protected by an additional lock
+	state         int           // Tracks state of node lifecycle
 
 	lock          sync.Mutex
 	lifecycles    []Lifecycle // All registered backends, services, and auxiliary services that have a lifecycle
@@ -320,20 +320,20 @@ func (n *Node) openDataDir() error {
 	}
 	// Lock the instance directory to prevent concurrent use by another instance as well as
 	// accidental use of the instance directory as a database.
-	release, _, err := fileutil.Flock(filepath.Join(instdir, "LOCK"))
-	if err != nil {
-		return convertFileLockError(err)
+	n.dirLock = flock.New(filepath.Join(instdir, "LOCK"))
+
+	if locked, err := n.dirLock.TryLock(); err != nil {
+		return err
+	} else if !locked {
+		return ErrDatadirUsed
 	}
-	n.dirLock = release
 	return nil
 }
 
 func (n *Node) closeDataDir() {
 	// Release instance directory lock.
-	if n.dirLock != nil {
-		if err := n.dirLock.Release(); err != nil {
-			n.log.Error("Can't release datadir lock", "err", err)
-		}
+	if n.dirLock != nil && n.dirLock.Locked() {
+		n.dirLock.Unlock()
 		n.dirLock = nil
 	}
 }