core/rawdb: fix freezer dir.Sync() failure on Windows

The atomicRename function calls dir.Sync() on a directory handle,
which is not supported on Windows and returns "Access is denied".
This caused truncateTail and resetTo to fail after already closing
the index file, leaving it in a closed state for subsequent reads.

Extract the directory sync into a platform-specific syncDir()
function: a no-op on Windows, and the existing fsync-with-EINVAL-
handling on Unix. This follows the same pattern already used in
triedb/pathdb/fileutils_{unix,windows}.go.

Fixes #34114

core/rawdb/freezer_utils.go

@@ -26,13 +26,7 @@ func atomicRename(src, dest string) error {
 	if err := os.Rename(src, dest); err != nil {
 		return err
 	}
-	dir, err := os.Open(filepath.Dir(src))
-	if err != nil {
-		return err
-	}
-	defer dir.Close()
-
-	return dir.Sync()
+	return syncDir(filepath.Dir(src))
 }
 
 // copyFrom copies data from 'srcPath' at offset 'offset' into 'destPath'.

core/rawdb/freezer_utils_unix.go

@@ -0,0 +1,49 @@
+// Copyright 2022 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+//go:build !windows
+// +build !windows
+
+package rawdb
+
+import (
+	"errors"
+	"os"
+	"syscall"
+)
+
+// syncDir ensures that the directory metadata (e.g. newly renamed files)
+// is flushed to durable storage.
+func syncDir(name string) error {
+	f, err := os.Open(name)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+
+	// Some file systems do not support fsyncing directories (e.g. some FUSE
+	// mounts). Ignore EINVAL in those cases.
+	if err := f.Sync(); err != nil {
+		if errors.Is(err, os.ErrInvalid) {
+			return nil
+		}
+		if patherr, ok := err.(*os.PathError); ok && patherr.Err == syscall.EINVAL {
+			return nil
+		}
+		return err
+	}
+	return nil
+}

core/rawdb/freezer_utils_windows.go

@@ -0,0 +1,26 @@
+// Copyright 2022 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+//go:build windows
+// +build windows
+
+package rawdb
+
+// syncDir is a no-op on Windows. Fsyncing a directory handle is not
+// supported and returns "Access is denied".
+func syncDir(name string) error {
+	return nil
+}