mount: support extended attributes

weed/filesys/xattr.go

@@ -0,0 +1,134 @@
+package filesys
+
+import (
+	"context"
+	"path/filepath"
+
+	"github.com/chrislusf/seaweedfs/weed/glog"
+	"github.com/chrislusf/seaweedfs/weed/pb/filer_pb"
+	"github.com/seaweedfs/fuse"
+)
+
+func getxattr(entry *filer_pb.Entry, req *fuse.GetxattrRequest, resp *fuse.GetxattrResponse) error {
+
+	if entry == nil {
+		return fuse.ErrNoXattr
+	}
+	if entry.Extended == nil {
+		return fuse.ErrNoXattr
+	}
+	data, found := entry.Extended[req.Name]
+	if !found {
+		return fuse.ErrNoXattr
+	}
+	if req.Position < uint32(len(data)) {
+		size := req.Size
+		if req.Position+size >= uint32(len(data)) {
+			size = uint32(len(data)) - req.Position
+		}
+		resp.Xattr = data[req.Position : req.Position+size]
+	}
+
+	return nil
+
+}
+
+func setxattr(entry *filer_pb.Entry, req *fuse.SetxattrRequest) error {
+
+	if entry == nil {
+		return fuse.EIO
+	}
+
+	if entry.Extended == nil {
+		entry.Extended = make(map[string][]byte)
+	}
+	data, _ := entry.Extended[req.Name]
+
+	newData := make([]byte, int(req.Position)+len(req.Xattr))
+
+	copy(newData, data)
+
+	copy(newData[int(req.Position):], req.Xattr)
+
+	entry.Extended[req.Name] = newData
+
+	return nil
+
+}
+
+func removexattr(entry *filer_pb.Entry, req *fuse.RemovexattrRequest) error {
+
+	if entry == nil {
+		return fuse.ErrNoXattr
+	}
+
+	if entry.Extended == nil {
+		return fuse.ErrNoXattr
+	}
+
+	_, found := entry.Extended[req.Name]
+
+	if !found {
+		return fuse.ErrNoXattr
+	}
+
+	delete(entry.Extended, req.Name)
+
+	return nil
+
+}
+
+func listxattr(entry *filer_pb.Entry, req *fuse.ListxattrRequest, resp *fuse.ListxattrResponse) error {
+
+	if entry == nil {
+		return fuse.EIO
+	}
+
+	for k := range entry.Extended {
+		resp.Append(k)
+	}
+
+	size := req.Size
+	if req.Position+size >= uint32(len(resp.Xattr)) {
+		size = uint32(len(resp.Xattr)) - req.Position
+	}
+
+	resp.Xattr = resp.Xattr[req.Position : req.Position+size]
+
+	return nil
+
+}
+
+func (wfs *WFS) maybeLoadEntry(ctx context.Context, dir, name string) (entry *filer_pb.Entry, err error) {
+
+	fullpath := filepath.Join(dir, name)
+	item := wfs.listDirectoryEntriesCache.Get(fullpath)
+	if item != nil && !item.Expired() {
+		entry = item.Value().(*filer_pb.Entry)
+		return
+	}
+	glog.V(3).Infof("read entry cache miss %s", fullpath)
+
+	err = wfs.WithFilerClient(ctx, func(client filer_pb.SeaweedFilerClient) error {
+
+		request := &filer_pb.LookupDirectoryEntryRequest{
+			Name:      name,
+			Directory: dir,
+		}
+
+		resp, err := client.LookupDirectoryEntry(ctx, request)
+		if err != nil {
+			glog.V(3).Infof("file attr read file %v: %v", request, err)
+			return fuse.ENOENT
+		}
+
+		entry = resp.Entry
+		if entry != nil {
+			wfs.listDirectoryEntriesCache.Set(fullpath, entry, wfs.option.EntryCacheTtl)
+		}
+
+		return nil
+	})
+
+	return
+}