From b29d009b14f11e4f22d6d26b5af184639b1eab46 Mon Sep 17 00:00:00 2001
From: Ben Lubar <ben.lubar@gmail.com>
Date: Sat, 21 Mar 2020 13:21:35 -0500
Subject: [PATCH] update structures; implement struct_field_info_extra

---
 library/LuaTypes.cpp                            | 10 +++++-----
 library/include/DataDefs.h                      | 10 +++++++++-
 library/xml                                     |  2 +-
 plugins/devel/check-structures-sanity/types.cpp |  2 +-
 4 files changed, 16 insertions(+), 8 deletions(-)

diff --git a/library/LuaTypes.cpp b/library/LuaTypes.cpp
index ad0f3e5e4..306538f51 100644
--- a/library/LuaTypes.cpp
+++ b/library/LuaTypes.cpp
@@ -508,8 +508,8 @@ static void read_field(lua_State *state, const struct_field_info *field, void *p
             return;
 
         case struct_field_info::CONTAINER:
-            if (!field->eid || !field->type->isContainer() ||
-                field->eid == ((container_identity*)field->type)->getIndexEnumType())
+            if (!field->extra || !field->extra->index_enum || !field->type->isContainer() ||
+                field->extra->index_enum == ((container_identity*)field->type)->getIndexEnumType())
             {
                 field->type->lua_read(state, 2, ptr);
                 return;
@@ -1445,7 +1445,7 @@ static void GetAdHocMetatable(lua_State *state, const struct_field_info *field)
         case struct_field_info::CONTAINER:
         {
             auto ctype = (container_identity*)field->type;
-            MakeContainerMetatable(state, ctype, ctype->getItemType(), -1, field->eid);
+            MakeContainerMetatable(state, ctype, ctype->getItemType(), -1, field->extra ? field->extra->index_enum : nullptr);
             break;
         }
 
@@ -1456,12 +1456,12 @@ static void GetAdHocMetatable(lua_State *state, const struct_field_info *field)
 
         case struct_field_info::STATIC_ARRAY:
             MakeContainerMetatable(state, &df::buffer_container_identity::base_instance,
-                                   field->type, field->count, field->eid);
+                                   field->type, field->count, field->extra ? field->extra->index_enum : nullptr);
             break;
 
         case struct_field_info::STL_VECTOR_PTR:
             MakeContainerMetatable(state, &df::identity_traits<std::vector<void*> >::identity,
-                                   field->type, -1, field->eid);
+                                   field->type, -1, field->extra ? field->extra->index_enum : nullptr);
             break;
 
         default:
diff --git a/library/include/DataDefs.h b/library/include/DataDefs.h
index 03bb7857f..a6639f7b1 100644
--- a/library/include/DataDefs.h
+++ b/library/include/DataDefs.h
@@ -252,6 +252,13 @@ namespace DFHack
         virtual void lua_write(lua_State *state, int fname_idx, void *ptr, int val_index);
     };
 
+    struct struct_field_info_extra {
+        enum_identity *index_enum;
+        type_identity *ref_target;
+        const char *union_tag_field;
+        const char *union_tag_attr;
+    };
+
     struct struct_field_info {
         enum Mode {
             END,
@@ -270,7 +277,7 @@ namespace DFHack
         size_t offset;
         type_identity *type;
         size_t count;
-        enum_identity *eid;
+        const struct_field_info_extra *extra;
     };
 
     class DFHACK_EXPORT struct_identity : public compound_identity {
@@ -452,6 +459,7 @@ namespace df
     using DFHack::struct_identity;
     using DFHack::union_identity;
     using DFHack::struct_field_info;
+    using DFHack::struct_field_info_extra;
     using DFHack::bitfield_item_info;
     using DFHack::bitfield_identity;
     using DFHack::enum_identity;
diff --git a/library/xml b/library/xml
index ef09097be..6ad3e99e1 160000
--- a/library/xml
+++ b/library/xml
@@ -1 +1 @@
-Subproject commit ef09097be76a58b5911b5bf65bee7c3cd6d7bb16
+Subproject commit 6ad3e99e1ed26f1b0af210f941ace905a70b50e7
diff --git a/plugins/devel/check-structures-sanity/types.cpp b/plugins/devel/check-structures-sanity/types.cpp
index 24d33301e..9e565215a 100644
--- a/plugins/devel/check-structures-sanity/types.cpp
+++ b/plugins/devel/check-structures-sanity/types.cpp
@@ -40,7 +40,7 @@ CheckedStructure::CheckedStructure(const struct_field_info *field) :
     }
 
     identity = field->type;
-    eid = field->eid;
+    eid = field->extra ? field->extra->index_enum : nullptr;
     inside_structure = true;
     switch (field->mode)
     {