Retry rename on lock induced failures (#16435)

* Retry rename on lock induced failures

Due to external locking on Windows it is possible for an
os.Rename to fail if the files or directories are being
used elsewhere.

This PR simply suggests retrying the rename again similar
to how we handle the os.Remove problems.

Fix #16427

Signed-off-by: Andrew Thornton <art27@cantab.net>

* resolve CI fail

Co-authored-by: techknowlogick <techknowlogick@gitea.io>

3 files changed, 30 insertions, 3 deletions

diff --git a/modules/log/file.go b/modules/log/file.go
index d5b38d4e01..79cbe740fd 100644
--- a/modules/log/file.go
+++ b/modules/log/file.go
@@ -177,7 +177,7 @@ func (log *FileLogger) DoRotate() error {
 
 		// close fd before rename
 		// Rename the file to its newfound home
-		if err = os.Rename(log.Filename, fname); err != nil {
+		if err = util.Rename(log.Filename, fname); err != nil {
 			return fmt.Errorf("Rotate: %v", err)
 		}
 
diff --git a/modules/storage/local.go b/modules/storage/local.go
index 46e5d60e6b..1329f722c2 100644
--- a/modules/storage/local.go
+++ b/modules/storage/local.go
@@ -96,7 +96,7 @@ func (l *LocalStorage) Save(path string, r io.Reader, size int64) (int64, error)
 		return 0, err
 	}
 
-	if err := os.Rename(tmp.Name(), p); err != nil {
+	if err := util.Rename(tmp.Name(), p); err != nil {
 		return 0, err
 	}
 
diff --git a/modules/util/remove.go b/modules/util/remove.go
index f2bbbc30b9..2310436525 100644
--- a/modules/util/remove.go
+++ b/modules/util/remove.go
@@ -33,7 +33,7 @@ func Remove(name string) error {
 	return err
 }
 
-// RemoveAll removes the named file or (empty) directory with at most 5 attempts.Remove
+// RemoveAll removes the named file or (empty) directory with at most 5 attempts.
 func RemoveAll(name string) error {
 	var err error
 	for i := 0; i < 5; i++ {
@@ -55,3 +55,30 @@ func RemoveAll(name string) error {
 	}
 	return err
 }
+
+// Rename renames (moves) oldpath to newpath with at most 5 attempts.
+func Rename(oldpath, newpath string) error {
+	var err error
+	for i := 0; i < 5; i++ {
+		err = os.Rename(oldpath, newpath)
+		if err == nil {
+			break
+		}
+		unwrapped := err.(*os.PathError).Err
+		if unwrapped == syscall.EBUSY || unwrapped == syscall.ENOTEMPTY || unwrapped == syscall.EPERM || unwrapped == syscall.EMFILE || unwrapped == syscall.ENFILE {
+			// try again
+			<-time.After(100 * time.Millisecond)
+			continue
+		}
+
+		if i == 0 && os.IsNotExist(err) {
+			return err
+		}
+
+		if unwrapped == syscall.ENOENT {
+			// it's already gone
+			return nil
+		}
+	}
+	return err
+}