1 files changed, 80 insertions, 0 deletions
diff --git a/weed/filesys/dir_link.go b/weed/filesys/dir_link.go
index 486dd0c9b..c15aed863 100644
--- a/weed/filesys/dir_link.go
+++ b/weed/filesys/dir_link.go
@@ -2,6 +2,7 @@ package filesys
 
 import (
 	"context"
+	"github.com/chrislusf/seaweedfs/weed/util"
 	"os"
 	"syscall"
 	"time"
@@ -13,9 +14,88 @@ import (
 	"github.com/seaweedfs/fuse/fs"
 )
 
+var _ = fs.NodeLinker(&Dir{})
 var _ = fs.NodeSymlinker(&Dir{})
 var _ = fs.NodeReadlinker(&File{})
 
+func (dir *Dir) Link(ctx context.Context, req *fuse.LinkRequest, old fs.Node) (fs.Node, error) {
+
+	oldFile, ok := old.(*File)
+	if !ok {
+		glog.Errorf("old node is not a file: %+v", old)
+	}
+
+	glog.V(4).Infof("Link: %v/%v -> %v/%v", oldFile.dir.FullPath(), oldFile.Name, dir.FullPath(), req.NewName)
+
+	if err := oldFile.maybeLoadEntry(ctx); err != nil {
+		return nil, err
+	}
+
+	// update old file to hardlink mode
+	var updateOldEntryRequest *filer_pb.UpdateEntryRequest
+	var hardLinkId filer.HardLinkId
+	if oldFile.entry.HardLinkId != 0 {
+		hardLinkId = filer.HardLinkId(oldFile.entry.HardLinkId)
+	} else {
+		// CreateLink 1.1 : split source entry into hardlink+empty_entry
+		hardLinkId = filer.HardLinkId(util.RandomInt64())
+		updateOldEntryRequest = &filer_pb.UpdateEntryRequest{
+			Directory: oldFile.dir.FullPath(),
+			Entry: &filer_pb.Entry{
+				Name:        oldFile.entry.Name,
+				IsDirectory: oldFile.entry.IsDirectory,
+				HardLinkId:  int64(hardLinkId),
+			},
+			Signatures: []int32{dir.wfs.signature},
+		}
+	}
+
+	// CreateLink 1.2 : update new file to hardlink mode
+	request := &filer_pb.CreateEntryRequest{
+		Directory: dir.FullPath(),
+		Entry: &filer_pb.Entry{
+			Name:        req.NewName,
+			IsDirectory: false,
+			HardLinkId:  int64(hardLinkId),
+		},
+		Signatures: []int32{dir.wfs.signature},
+	}
+
+	// apply changes to the filer, and also apply to local metaCache
+	err := dir.wfs.WithFilerClient(func(client filer_pb.SeaweedFilerClient) error {
+
+		dir.wfs.mapPbIdFromLocalToFiler(request.Entry)
+		defer dir.wfs.mapPbIdFromFilerToLocal(request.Entry)
+
+		if updateOldEntryRequest != nil {
+			if err := filer_pb.UpdateEntry(client, updateOldEntryRequest); err != nil {
+				glog.V(0).Infof("Link %v/%v -> %s/%s: %v", oldFile.dir.FullPath(), oldFile.Name, dir.FullPath(), req.NewName, err)
+				return fuse.EIO
+			}
+			dir.wfs.metaCache.UpdateEntry(context.Background(), filer.FromPbEntry(updateOldEntryRequest.Directory, updateOldEntryRequest.Entry))
+			oldFile.entry.HardLinkId = int64(hardLinkId)
+		}
+
+		if err := filer_pb.CreateEntry(client, request); err != nil {
+			glog.V(0).Infof("Link %v/%v -> %s/%s: %v", oldFile.dir.FullPath(), oldFile.Name, dir.FullPath(), req.NewName, err)
+			return fuse.EIO
+		}
+		dir.wfs.metaCache.InsertEntry(context.Background(), filer.FromPbEntry(request.Directory, request.Entry))
+
+		return nil
+	})
+
+	// create new file node
+	newNode := dir.newFile(req.NewName, request.Entry)
+	newFile := newNode.(*File)
+	if err := newFile.maybeLoadEntry(ctx); err != nil {
+		return nil, err
+	}
+
+	return newFile, err
+
+}
+
 func (dir *Dir) Symlink(ctx context.Context, req *fuse.SymlinkRequest) (fs.Node, error) {
 
 	glog.V(4).Infof("Symlink: %v/%v to %v", dir.FullPath(), req.NewName, req.Target)