From 83cf94ad2dea74e5f9a881a617d06c42cbb7ba49 Mon Sep 17 00:00:00 2001
From: Chris Lu <chris.lu@gmail.com>
Date: Mon, 19 Apr 2021 10:58:25 -0700
Subject: [PATCH] delay new file creation unless file is opened exclusively

---
 weed/filesys/dir.go  | 28 ++++++++++++++++++++++++----
 weed/filesys/file.go |  1 +
 2 files changed, 25 insertions(+), 4 deletions(-)

diff --git a/weed/filesys/dir.go b/weed/filesys/dir.go
index 1dc2ab939..6ee20974b 100644
--- a/weed/filesys/dir.go
+++ b/weed/filesys/dir.go
@@ -28,6 +28,7 @@ type Dir struct {
 }
 
 var _ = fs.Node(&Dir{})
+
 //var _ = fs.NodeIdentifier(&Dir{})
 var _ = fs.NodeCreater(&Dir{})
 var _ = fs.NodeMknoder(&Dir{})
@@ -140,19 +141,38 @@ func (dir *Dir) newDirectory(fullpath util.FullPath) fs.Node {
 func (dir *Dir) Create(ctx context.Context, req *fuse.CreateRequest,
 	resp *fuse.CreateResponse) (fs.Node, fs.Handle, error) {
 
-	request, err := dir.doCreateEntry(req.Name, req.Mode, req.Uid, req.Gid, req.Flags&fuse.OpenExclusive != 0)
+	exclusive := req.Flags&fuse.OpenExclusive != 0
+	isDirectory := req.Mode&os.ModeDir > 0
 
-	if err != nil {
-		return nil, nil, err
+	if exclusive || isDirectory {
+		_, err := dir.doCreateEntry(req.Name, req.Mode, req.Uid, req.Gid, exclusive)
+		if err != nil {
+			return nil, nil, err
+		}
 	}
 	var node fs.Node
-	if request.Entry.IsDirectory {
+	if isDirectory {
 		node = dir.newDirectory(util.NewFullPath(dir.FullPath(), req.Name))
 		return node, nil, nil
 	}
 
 	node = dir.newFile(req.Name)
 	file := node.(*File)
+	file.entry = &filer_pb.Entry{
+		Name:        req.Name,
+		IsDirectory: req.Mode&os.ModeDir > 0,
+		Attributes: &filer_pb.FuseAttributes{
+			Mtime:       time.Now().Unix(),
+			Crtime:      time.Now().Unix(),
+			FileMode:    uint32(req.Mode &^ dir.wfs.option.Umask),
+			Uid:         req.Uid,
+			Gid:         req.Gid,
+			Collection:  dir.wfs.option.Collection,
+			Replication: dir.wfs.option.Replication,
+			TtlSec:      dir.wfs.option.TtlSec,
+		},
+	}
+	file.dirtyMetadata = true
 	fh := dir.wfs.AcquireHandle(file, req.Uid, req.Gid)
 	return file, fh, nil
 
diff --git a/weed/filesys/file.go b/weed/filesys/file.go
index 2e37c6e0e..5fb4d8d11 100644
--- a/weed/filesys/file.go
+++ b/weed/filesys/file.go
@@ -265,6 +265,7 @@ func (file *File) maybeLoadEntry(ctx context.Context) (entry *filer_pb.Entry, er
 	file.wfs.handlesLock.Lock()
 	handle, found := file.wfs.handles[file.Id()]
 	file.wfs.handlesLock.Unlock()
+	entry = file.entry
 	if found {
 		glog.V(4).Infof("maybeLoadEntry found opened file %s/%s: %v %v", file.dir.FullPath(), file.Name, handle.f.entry, entry)
 		entry = handle.f.entry