move extension_registry declarations out of msg_internal.h

PiperOrigin-RevId: 478407599

upb/extension_registry.h

@@ -71,13 +71,30 @@ extern "C" {
  * reflection do not need to populate a upb_ExtensionRegistry directly.
  */
 
-struct upb_ExtensionRegistry;
 typedef struct upb_ExtensionRegistry upb_ExtensionRegistry;
 
-/* Creates a upb_ExtensionRegistry in the given arena.  The arena must outlive
- * any use of the extreg. */
+// Creates a upb_ExtensionRegistry in the given arena.
+// The arena must outlive any use of the extreg.
 upb_ExtensionRegistry* upb_ExtensionRegistry_New(upb_Arena* arena);
 
+// EVERYTHING BELOW THIS LINE IS INTERNAL - DO NOT USE /////////////////////////
+
+typedef struct upb_MiniTable upb_MiniTable;
+typedef struct upb_MiniTable_Extension upb_MiniTable_Extension;
+
+// Adds the given extension info for message type |l| and field number |num|
+// into the registry. Returns false if this message type and field number were
+// already in the map, or if memory allocation fails.
+bool _upb_extreg_add(upb_ExtensionRegistry* r,
+                     const upb_MiniTable_Extension** e, size_t count);
+
+// Looks up the extension (if any) defined for message type |l| and field
+// number |num|. If an extension was found, copies the field info into |*ext|
+// and returns true. Otherwise returns false.
+const upb_MiniTable_Extension* _upb_extreg_get(const upb_ExtensionRegistry* r,
+                                               const upb_MiniTable* l,
+                                               uint32_t num);
+
 #ifdef __cplusplus
 } /* extern "C" */
 #endif

upb/msg_internal.h

@@ -226,11 +226,13 @@ struct upb_MiniTable {
   _upb_FastTable_Entry fasttable[];
 };
 
-typedef struct {
+typedef struct upb_MiniTable_Extension upb_MiniTable_Extension;
+
+struct upb_MiniTable_Extension {
   upb_MiniTable_Field field;
   const upb_MiniTable* extendee;
   upb_MiniTable_Sub sub; /* NULL unless submessage or proto2 enum */
-} upb_MiniTable_Extension;
+};
 
 typedef struct {
   const upb_MiniTable** msgs;
@@ -253,21 +255,6 @@ UPB_INLINE uint64_t upb_MiniTable_requiredmask(const upb_MiniTable* l) {
   return ((1ULL << n) - 1) << 1;
 }
 
-/** upb_ExtensionRegistry *****************************************************/
-
-/* Adds the given extension info for message type |l| and field number |num|
- * into the registry. Returns false if this message type and field number were
- * already in the map, or if memory allocation fails. */
-bool _upb_extreg_add(upb_ExtensionRegistry* r,
-                     const upb_MiniTable_Extension** e, size_t count);
-
-/* Looks up the extension (if any) defined for message type |l| and field
- * number |num|.  If an extension was found, copies the field info into |*ext|
- * and returns true. Otherwise returns false. */
-const upb_MiniTable_Extension* _upb_extreg_get(const upb_ExtensionRegistry* r,
-                                               const upb_MiniTable* l,
-                                               uint32_t num);
-
 /** upb_Message ***************************************************************/
 
 /* Internal members of a upb_Message that track unknown fields and/or