3 files changed, 26 insertions, 0 deletions
diff --git a/upb/pb/decoder.c b/upb/pb/decoder.c
index 182ecc9..79142bf 100644
--- a/upb/pb/decoder.c
+++ b/upb/pb/decoder.c
@@ -543,6 +543,9 @@ UPB_NOINLINE int32_t upb_pbdecoder_checktag_slow(upb_pbdecoder *d,
 
 int32_t upb_pbdecoder_skipunknown(upb_pbdecoder *d, int32_t fieldnum,
                                   uint8_t wire_type) {
+  upb_addunknown_handlerfunc *addunknown;
+  const void* hd;
+
   if (fieldnum >= 0)
     goto have_tag;
 
@@ -596,6 +599,14 @@ have_tag:
     }
 
     if (d->top->groupnum >= 0) {
+      addunknown = (upb_addunknown_handlerfunc *)upb_handlers_gethandler(
+          (d->top->sink).handlers, UPB_UNKNOWN_SELECTOR);
+      if (addunknown != NULL) {
+        hd = upb_handlers_gethandlerdata((d->top->sink).handlers,
+                                         UPB_UNKNOWN_SELECTOR);
+        addunknown((d->top->sink).closure, hd, d->checkpoint,
+                   d->ptr - d->checkpoint);
+      }
       return DECODE_OK;
     }
 
diff --git a/upb/pb/encoder.c b/upb/pb/encoder.c
index b457867..b8e9191 100644
--- a/upb/pb/encoder.c
+++ b/upb/pb/encoder.c
@@ -374,6 +374,12 @@ static void *encode_startdelimfield(void *c, const void *hd) {
   return ok ? c : UPB_BREAK;
 }
 
+static bool encode_unknown(void *c, const void *hd, const char *buf,
+                           size_t len) {
+  UPB_UNUSED(hd);
+  return encode_bytes(c, buf, len) && commit(c);
+}
+
 static bool encode_enddelimfield(void *c, const void *hd) {
   UPB_UNUSED(hd);
   return end_delim(c);
@@ -436,6 +442,7 @@ static void newhandlers_callback(const void *closure, upb_handlers *h) {
 
   upb_handlers_setstartmsg(h, startmsg, NULL);
   upb_handlers_setendmsg(h, endmsg, NULL);
+  upb_handlers_setunknown(h, encode_unknown, NULL);
 
   m = upb_handlers_msgdef(h);
   for(upb_msg_field_begin(&i, m);
@@ -564,3 +571,9 @@ upb_pb_encoder *upb_pb_encoder_create(upb_env *env, const upb_handlers *h,
 }
 
 upb_sink *upb_pb_encoder_input(upb_pb_encoder *e) { return &e->input_; }
+
+void upb_pb_encoder_encode_unknown(upb_pb_encoder *p, const char *buf,
+                                   size_t size) {
+  encode_bytes(p, buf, size);
+  commit(p);
+}
diff --git a/upb/pb/encoder.h b/upb/pb/encoder.h
index 41b7e7b..3d8dce1 100644
--- a/upb/pb/encoder.h
+++ b/upb/pb/encoder.h
@@ -64,6 +64,8 @@ const upb_handlers *upb_pb_encoder_newhandlers(const upb_msgdef *m,
 upb_sink *upb_pb_encoder_input(upb_pb_encoder *p);
 upb_pb_encoder* upb_pb_encoder_create(upb_env* e, const upb_handlers* h,
                                       upb_bytessink* output);
+void upb_pb_encoder_encode_unknown(upb_pb_encoder* p, const char* buf,
+                                   size_t size);
 
 UPB_END_EXTERN_C