proto, internal/impl: store unknown MessageSet items in non-mset format
In the v1 implementation, unknown MessageSet items are stored in a
message's unknown fields section in non-MessageSet format. For example,
consider a MessageSet containing an item with type_id T and value V.
If the type_id is not resolvable, the item will be placed in the unknown
fields as a bytes-valued field with number T and contents V. This
conversion is then reversed when marshaling a MessageSet containing
unknown fields.
Preserve this behavior in v2.
One consequence of this change is that actual unknown fields in a
MessageSet (any field other than 1) are now discarded. This matches
the previous behavior.
Change-Id: I3d913613f84e0ae82481078dbc91cb25628651cc
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/205697
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
diff --git a/internal/impl/codec_messageset.go b/internal/impl/codec_messageset.go
index 0b3746d..d78afeb 100644
--- a/internal/impl/codec_messageset.go
+++ b/internal/impl/codec_messageset.go
@@ -13,48 +13,36 @@
"google.golang.org/protobuf/internal/flags"
)
-func makeMessageSetFieldCoder(mi *MessageInfo) pointerCoderFuncs {
- return pointerCoderFuncs{
- size: func(p pointer, tagsize int, opts marshalOptions) int {
- return sizeMessageSet(mi, p, tagsize, opts)
- },
- marshal: func(b []byte, p pointer, wiretag uint64, opts marshalOptions) ([]byte, error) {
- return marshalMessageSet(mi, b, p, wiretag, opts)
- },
- unmarshal: func(b []byte, p pointer, wtyp wire.Type, opts unmarshalOptions) (int, error) {
- return unmarshalMessageSet(mi, b, p, wtyp, opts)
- },
- }
-}
-
-func sizeMessageSet(mi *MessageInfo, p pointer, tagsize int, opts marshalOptions) (n int) {
- ext := *p.Extensions()
- if ext == nil {
+func sizeMessageSet(mi *MessageInfo, p pointer, opts marshalOptions) (size int) {
+ if !flags.ProtoLegacy {
return 0
}
+
+ ext := *p.Apply(mi.extensionOffset).Extensions()
for _, x := range ext {
xi := mi.extensionFieldInfo(x.Type())
if xi.funcs.size == nil {
continue
}
num, _ := wire.DecodeTag(xi.wiretag)
- n += messageset.SizeField(num)
- n += xi.funcs.size(x.Value(), wire.SizeTag(messageset.FieldMessage), opts)
+ size += messageset.SizeField(num)
+ size += xi.funcs.size(x.Value(), wire.SizeTag(messageset.FieldMessage), opts)
}
- return n
+
+ unknown := *p.Apply(mi.unknownOffset).Bytes()
+ size += messageset.SizeUnknown(unknown)
+
+ return size
}
-func marshalMessageSet(mi *MessageInfo, b []byte, p pointer, wiretag uint64, opts marshalOptions) ([]byte, error) {
+func marshalMessageSet(mi *MessageInfo, b []byte, p pointer, opts marshalOptions) ([]byte, error) {
if !flags.ProtoLegacy {
return b, errors.New("no support for message_set_wire_format")
}
- ext := *p.Extensions()
- if ext == nil {
- return b, nil
- }
+
+ ext := *p.Apply(mi.extensionOffset).Extensions()
switch len(ext) {
case 0:
- return b, nil
case 1:
// Fast-path for one extension: Don't bother sorting the keys.
for _, x := range ext {
@@ -64,7 +52,6 @@
return b, err
}
}
- return b, nil
default:
// Sort the keys to provide a deterministic encoding.
// Not sure this is required, but the old code does it.
@@ -80,8 +67,15 @@
return b, err
}
}
- return b, nil
}
+
+ unknown := *p.Apply(mi.unknownOffset).Bytes()
+ b, err := messageset.AppendUnknown(b, unknown)
+ if err != nil {
+ return b, err
+ }
+
+ return b, nil
}
func marshalMessageSetField(mi *MessageInfo, b []byte, x ExtensionField, opts marshalOptions) ([]byte, error) {
@@ -96,24 +90,25 @@
return b, nil
}
-func unmarshalMessageSet(mi *MessageInfo, b []byte, p pointer, wtyp wire.Type, opts unmarshalOptions) (int, error) {
+func unmarshalMessageSet(mi *MessageInfo, b []byte, p pointer, opts unmarshalOptions) (int, error) {
if !flags.ProtoLegacy {
return 0, errors.New("no support for message_set_wire_format")
}
- if wtyp != wire.StartGroupType {
- return 0, errUnknown
- }
- ep := p.Extensions()
+
+ ep := p.Apply(mi.extensionOffset).Extensions()
if *ep == nil {
*ep = make(map[int32]ExtensionField)
}
ext := *ep
- num, v, n, err := messageset.ConsumeFieldValue(b, true)
- if err != nil {
- return 0, err
- }
- if _, err := mi.unmarshalExtension(v, num, wire.BytesType, ext, opts); err != nil {
- return 0, err
- }
- return n, nil
+ unknown := p.Apply(mi.unknownOffset).Bytes()
+ err := messageset.Unmarshal(b, true, func(num wire.Number, v []byte) error {
+ _, err := mi.unmarshalExtension(v, num, wire.BytesType, ext, opts)
+ if err == errUnknown {
+ *unknown = wire.AppendTag(*unknown, num, wire.BytesType)
+ *unknown = append(*unknown, v...)
+ return nil
+ }
+ return err
+ })
+ return len(b), err
}