Pass destination attribute to File.GetAttr.

fuse/api.go

@@ -170,7 +170,7 @@ type File interface {
 	// The methods below may be called on closed files, due to
 	// concurrency.  In that case, you should return EBADF.
 	Truncate(size uint64) Status
-	GetAttr() (*Attr, Status)
+	GetAttr(out *Attr) (Status)
 	Chown(uid uint32, gid uint32) Status
 	Chmod(perms uint32) Status
 	Utimens(atimeNs int64, mtimeNs int64) Status

fuse/defaultfile.go

@@ -35,8 +35,8 @@ func (f *DefaultFile) Release() {
 
 }
 
-func (f *DefaultFile) GetAttr() (*Attr, Status) {
-	return nil, ENOSYS
+func (f *DefaultFile) GetAttr(*Attr) Status {
+	return ENOSYS
 }
 
 func (f *DefaultFile) Fsync(flags int) (code Status) {

fuse/files.go

@@ -26,8 +26,10 @@ func (f *DataFile) String() string {
 	return fmt.Sprintf("DataFile(%x)", f.data[:l])
 }
 
-func (f *DataFile) GetAttr() (*Attr, Status) {
-	return &Attr{Mode: S_IFREG | 0644, Size: uint64(len(f.data))}, OK
+func (f *DataFile) GetAttr(out *Attr) Status {
+	out.Mode = S_IFREG | 0644
+	out.Size = uint64(len(f.data))
+	return OK
 }
 
 func NewDataFile(data []byte) *DataFile {
@@ -52,6 +54,8 @@ type DevNullFile struct {
 	DefaultFile
 }
 
+var _ = (File)((*DevNullFile)(nil))
+
 func NewDevNullFile() *DevNullFile {
 	return new(DevNullFile)
 }
@@ -134,15 +138,14 @@ func (f *LoopbackFile) Chown(uid uint32, gid uint32) Status {
 	return ToStatus(f.File.Chown(int(uid), int(gid)))
 }
 
-func (f *LoopbackFile) GetAttr() (*Attr, Status) {
+func (f *LoopbackFile) GetAttr(a *Attr) Status {
 	st := syscall.Stat_t{}
 	err := syscall.Fstat(int(f.File.Fd()), &st)
 	if err != nil {
-		return nil, ToStatus(err)
+		return ToStatus(err)
 	}
-	a := &Attr{}
 	a.FromStat(&st)
-	return a, OK
+	return OK
 }
 
 ////////////////////////////////////////////////////////////////

fuse/memnode.go

@@ -147,9 +147,10 @@ func (n *memNodeFile) InnerFile() File {
 
 func (n *memNodeFile) Flush() Status {
 	code := n.LoopbackFile.Flush()
-	fi, _ := n.LoopbackFile.GetAttr()
-	n.node.info.Size = fi.Size
-	n.node.info.Blocks = fi.Blocks
+	var a Attr
+	n.LoopbackFile.GetAttr(&a)
+	n.node.info.Size = a.Size
+	n.node.info.Blocks = a.Blocks
 	return code
 }
 

fuse/pathfs.go

@@ -527,8 +527,7 @@ func (n *pathInode) GetAttr(out *Attr, file File, context *Context) (code Status
 	}
 
 	if file != nil {
-		fi, code = file.GetAttr()
-		*out = *fi
+		code = file.GetAttr(out)
 	}
 
 	if file == nil || code == ENOSYS || code == EBADF {

unionfs/unionfs.go

@@ -1007,12 +1007,10 @@ func (fs *unionFsFile) SetInode(node *fuse.Inode) {
 	fs.node = node
 }
 
-func (fs *unionFsFile) GetAttr() (*fuse.Attr, fuse.Status) {
-	fi, code := fs.File.GetAttr()
-	if fi != nil {
-		f := *fi
-		fi = &f
-		fi.Mode |= 0200
-	}
-	return fi, code
+func (fs *unionFsFile) GetAttr(out *fuse.Attr) fuse.Status {
+	code := fs.File.GetAttr(out)
+	if code.Ok() {
+		out.Mode |= 0200
+	}
+	return code
 }