lib9p

commit d177d8ad7a393f210febe989023a2b4b207a34c2
parent 6c42146499ecb3aba36c46a0a621e59389137434
Author: Matsuda Kenji <info@mtkn.jp>
Date:   Wed, 29 Nov 2023 17:40:37 +0900

fix wstat

Diffstat:
M
diskfs/stat_unix.go
 | 
49
++++++++++++++++++++++++++++++-------------------

1 file changed, 30 insertions(+), 19 deletions(-)
diff --git a/diskfs/stat_unix.go b/diskfs/stat_unix.go
@@ -95,28 +95,20 @@ func (f *File) stat() (*lib9p.FileInfo, error) {
 // wstat is the real implementation of File.WStat.
 // TODO: when error occurs, file stat should be restored.
 func (f *File) wstat(s *lib9p.Stat) error {
-	file, err := os.OpenFile(path.Join(f.fs.rootPath, f.path), os.O_RDWR, 0)
-	if err != nil {
-		return err
-	}
-	defer file.Close()
-
+	var file *os.File
 	fi, err := f.Stat()
 	if err != nil {
 		return fmt.Errorf("stat: %v", err)
 	}
-
 	oldStat := fi.Sys().(*lib9p.Stat)
-
-	if s.Name != oldStat.Name {
-		// TODO: check neither Names contains "/"
-		oldpath := path.Join(f.fs.rootPath, path.Dir(f.path), oldStat.Name)
-		newpath := path.Join(f.fs.rootPath, path.Dir(f.path), s.Name)
-		if err := os.Rename(oldpath, newpath); err != nil {
-			return fmt.Errorf("rename: %v", err)
-		}
-	}
 	if s.Length != oldStat.Length {
+		if file == nil {
+			file, err = os.OpenFile(path.Join(f.fs.rootPath, f.path), os.O_RDWR, 0)
+			if err != nil {
+				return err
+			}
+			defer file.Close()
+		}
 		if err := file.Truncate(s.Length); err != nil {
 			return fmt.Errorf("truncate: %v", err)
 		}
@@ -126,6 +118,13 @@ func (f *File) wstat(s *lib9p.Stat) error {
 		}
 	}
 	if s.Mode != oldStat.Mode {
+		if file == nil {
+			file, err = os.OpenFile(path.Join(f.fs.rootPath, f.path), os.O_RDWR, 0)
+			if err != nil {
+				return err
+			}
+			defer file.Close()
+		}
 		if err := file.Chmod(s.Mode); err != nil {
 			return fmt.Errorf("chmod: %v", err)
 		}
@@ -136,7 +135,6 @@ func (f *File) wstat(s *lib9p.Stat) error {
 			return fmt.Errorf("chtimes: %v", err)
 		}
 	}
-
 	if s.Gid != oldStat.Gid {
 		group, err := user.LookupGroup(s.Gid)
 		if err != nil {
@@ -154,12 +152,25 @@ func (f *File) wstat(s *lib9p.Stat) error {
 		if err != nil {
 			return fmt.Errorf("convert gid: %v", err)
 		}
-
+		if file == nil {
+			file, err = os.OpenFile(path.Join(f.fs.rootPath, f.path), os.O_RDWR, 0)
+			if err != nil {
+				return err
+			}
+			defer file.Close()
+		}
 		if err := file.Chown(u, g); err != nil {
 			return fmt.Errorf("chown: %v", err)
 		}
 	}
-
+	if s.Name != oldStat.Name {
+		// TODO: check neither Names contains "/"
+		oldpath := path.Join(f.fs.rootPath, path.Dir(f.path), oldStat.Name)
+		newpath := path.Join(f.fs.rootPath, path.Dir(f.path), s.Name)
+		if err := os.Rename(oldpath, newpath); err != nil {
+			return fmt.Errorf("rename: %v", err)
+		}
+	}
 	return nil
 }