From 000d11daab57c2a264fbc3125a982ba5cbd4d71a Mon Sep 17 00:00:00 2001
From: Stinkfist0 <stinkfist0@gmail.com>
Date: Fri, 21 Dec 2018 12:06:35 +0200
Subject: [PATCH] IfcFile: possibility to mark an entity as modified so that
 potential cache is invalidated.

---
 src/ifcparse/IfcFile.h    | 4 ++++
 src/ifcparse/IfcParse.cpp | 9 ++++++++-
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/src/ifcparse/IfcFile.h b/src/ifcparse/IfcFile.h
index 1e871412fe..66f5c86159 100644
--- a/src/ifcparse/IfcFile.h
+++ b/src/ifcparse/IfcFile.h
@@ -148,6 +148,10 @@ public:
 	/// in the first function argument.
 	IfcEntityList::ptr traverse(IfcUtil::IfcBaseClass* instance, int max_level=-1);
 
+	/// Marks entity as modified so that potential cache for it is invalidated.
+	/// @todo Currently the whole cache is invalidated. Implement more fine-grained invalidation.
+	void mark_entity_as_modified(int id);
+
 #ifdef USE_MMAP
 	bool Init(const std::string& fn, bool mmap=false);
 #else
diff --git a/src/ifcparse/IfcParse.cpp b/src/ifcparse/IfcParse.cpp
index cd904790af..9e2b3bb41d 100644
--- a/src/ifcparse/IfcParse.cpp
+++ b/src/ifcparse/IfcParse.cpp
@@ -1213,7 +1213,9 @@ void IfcEntityInstanceData::setArgument(unsigned int i, Argument* a, IfcUtil::Ar
 	if (this->file) {
 		register_inverse_visitor visitor(*this->file, *this);
 		apply_individual_instance_visitor(copy).apply(visitor);
-	}	
+
+		this->file->mark_entity_as_modified(id_);
+	}
 
 	if (i < attributes_.size()) {
 		attributes_[i] = copy;
@@ -1429,6 +1431,11 @@ IfcEntityList::ptr IfcFile::traverse(IfcUtil::IfcBaseClass* instance, int max_le
 	return IfcParse::traverse(instance, max_level);
 }
 
+void IfcFile::mark_entity_as_modified(int /*id*/)
+{
+	by_ref_cached_.clear();
+}
+
 void IfcFile::addEntities(IfcEntityList::ptr es) {
 	for( IfcEntityList::it i = es->begin(); i != es->end(); ++ i ) {
 		addEntity(*i);