Put oneofs in the same table as fields. (#60)

* Put oneofs in the same table as fields.

Oneofs and fields are not allowed to have names that conflict,
so we might as well put them all in the same table.  This also
allows an efficient operation that looks for both fields and
oneofs in a single lookup.

Added support for OneofDef to Lua to allow testing of this.

* Addressed PR comments.

1 files changed, 23 insertions, 13 deletions

diff --git a/upb/def.h b/upb/def.h
index 87e1766..2cfaebc 100644
--- a/upb/def.h
+++ b/upb/def.h
@@ -668,6 +668,10 @@ UPB_END_EXTERN_C
 typedef upb_inttable_iter upb_msg_field_iter;
 typedef upb_strtable_iter upb_msg_oneof_iter;
 
+/* Well-known field tag numbers for map-entry messages. */
+#define UPB_MAPENTRY_KEY   1
+#define UPB_MAPENTRY_VALUE 2
+
 #ifdef __cplusplus
 
 /* Structure that describes a single .proto message type.
@@ -921,16 +925,20 @@ UPB_REFCOUNTED_CMETHODS(upb_msgdef, upb_msgdef_upcast2)
 
 bool upb_msgdef_freeze(upb_msgdef *m, upb_status *status);
 
+upb_msgdef *upb_msgdef_dup(const upb_msgdef *m, const void *owner);
 const char *upb_msgdef_fullname(const upb_msgdef *m);
 const char *upb_msgdef_name(const upb_msgdef *m);
+int upb_msgdef_numoneofs(const upb_msgdef *m);
 upb_syntax_t upb_msgdef_syntax(const upb_msgdef *m);
-bool upb_msgdef_setfullname(upb_msgdef *m, const char *fullname, upb_status *s);
 
-upb_msgdef *upb_msgdef_dup(const upb_msgdef *m, const void *owner);
 bool upb_msgdef_addfield(upb_msgdef *m, upb_fielddef *f, const void *ref_donor,
                          upb_status *s);
 bool upb_msgdef_addoneof(upb_msgdef *m, upb_oneofdef *o, const void *ref_donor,
                          upb_status *s);
+bool upb_msgdef_setfullname(upb_msgdef *m, const char *fullname, upb_status *s);
+void upb_msgdef_setmapentry(upb_msgdef *m, bool map_entry);
+bool upb_msgdef_mapentry(const upb_msgdef *m);
+bool upb_msgdef_setsyntax(upb_msgdef *m, upb_syntax_t syntax);
 
 /* Field lookup in a couple of different variations:
  *   - itof = int to field
@@ -972,19 +980,21 @@ UPB_INLINE upb_oneofdef *upb_msgdef_ntoo_mutable(upb_msgdef *m,
   return (upb_oneofdef *)upb_msgdef_ntoo(m, name, len);
 }
 
-void upb_msgdef_setmapentry(upb_msgdef *m, bool map_entry);
-bool upb_msgdef_mapentry(const upb_msgdef *m);
-bool upb_msgdef_setsyntax(upb_msgdef *m, upb_syntax_t syntax);
+/* Lookup of either field or oneof by name.  Returns whether either was found.
+ * If the return is true, then the found def will be set, and the non-found
+ * one set to NULL. */
+bool upb_msgdef_lookupname(const upb_msgdef *m, const char *name, size_t len,
+                           const upb_fielddef **f, const upb_oneofdef **o);
 
-/* Well-known field tag numbers for map-entry messages. */
-#define UPB_MAPENTRY_KEY   1
-#define UPB_MAPENTRY_VALUE 2
-
-const upb_oneofdef *upb_msgdef_findoneof(const upb_msgdef *m,
-                                          const char *name);
-int upb_msgdef_numoneofs(const upb_msgdef *m);
+UPB_INLINE bool upb_msgdef_lookupnamez(const upb_msgdef *m, const char *name,
+                                       const upb_fielddef **f,
+                                       const upb_oneofdef **o) {
+  return upb_msgdef_lookupname(m, name, strlen(name), f, o);
+}
 
-/* upb_msg_field_iter i;
+/* Iteration over fields and oneofs.  For example:
+ *
+ * upb_msg_field_iter i;
  * for(upb_msg_field_begin(&i, m);
  *     !upb_msg_field_done(&i);
  *     upb_msg_field_next(&i)) {