Fix race conditions in the config compiler.

Fixes #5335

lib/config/configitem.cpp

@@ -103,12 +103,12 @@ ExpressionList::Ptr ConfigItem::GetExpressionList(void) const
 	return m_ExpressionList;
 }
 
-void ConfigItem::Link(void)
+ExpressionList::Ptr ConfigItem::GetLinkedExpressionList(void)
 {
 	ASSERT(OwnsLock());
 
 	if (m_LinkedExpressionList)
-		return;
+		return m_LinkedExpressionList;
 
 	m_LinkedExpressionList = make_shared<ExpressionList>();
 
@@ -121,31 +121,25 @@ void ConfigItem::Link(void)
 			    " exist (" << m_DebugInfo << ")";
 			ConfigCompilerContext::GetInstance()->AddMessage(true, message.str());
 		} else {
-			parent->Link();
+			ExpressionList::Ptr pexprl;
+
+			{
+				ObjectLock olock(parent);
+				pexprl = parent->GetLinkedExpressionList();
+			}
 
-			ExpressionList::Ptr pexprl = parent->m_LinkedExpressionList;
 			m_LinkedExpressionList->AddExpression(Expression("", OperatorExecute, pexprl, m_DebugInfo));
 		}
 	}
 
 	m_LinkedExpressionList->AddExpression(Expression("", OperatorExecute, m_ExpressionList, m_DebugInfo));
-}
-
-ExpressionList::Ptr ConfigItem::GetLinkedExpressionList(void)
-{
-	ASSERT(OwnsLock());
-
-	if (!m_LinkedExpressionList)
-		Link();
 
 	return m_LinkedExpressionList;
 }
 
 Dictionary::Ptr ConfigItem::GetProperties(void)
 {
-	ASSERT(!OwnsLock());
+	ASSERT(OwnsLock());
-
-	ObjectLock olock(this);
 
 	if (!m_Properties) {
 		m_Properties = make_shared<Dictionary>();
@@ -181,7 +175,13 @@ DynamicObject::Ptr ConfigItem::Commit(void)
 	if (IsAbstract())
 		return DynamicObject::Ptr();
 
-	Dictionary::Ptr properties = GetProperties();
+	Dictionary::Ptr properties;
+
+	{
+		ObjectLock olock(this);
+
+		properties = GetProperties();
+	}
 
 	DynamicObject::Ptr dobj = dtype->CreateObject(properties);
 	dobj->Register();

lib/config/configitem.h

@@ -65,7 +65,6 @@ public:
 	static void DiscardItems(void);
 
 private:
-	void Link(void);
 	ExpressionList::Ptr GetExpressionList(void) const;
 
 	String m_Type; /**< The object type. */

lib/config/configtype.cpp

@@ -79,11 +79,21 @@ void ConfigType::ValidateItem(const ConfigItem::Ptr& item)
 	if (item->IsAbstract())
 		return;
 
-	Dictionary::Ptr attrs = item->GetProperties();
+	Dictionary::Ptr attrs;
+	DebugInfo debugInfo;
+	String type, name;
+
+	{
+		ObjectLock olock(item);
+
+		attrs = item->GetProperties();
+		debugInfo = item->GetDebugInfo();
+		type = item->GetType();
+		name = item->GetName();
+	}
 
 	std::vector<String> locations;
-	DebugInfo debugInfo  = item->GetDebugInfo();
+	locations.push_back("Object '" + name + "' (Type: '" + type + "') at " + debugInfo.Path + ":" + Convert::ToString(debugInfo.FirstLine));
-	locations.push_back("Object '" + item->GetName() + "' (Type: '" + item->GetType() + "') at " + debugInfo.Path + ":" + Convert::ToString(debugInfo.FirstLine));
 
 	std::vector<TypeRuleList::Ptr> ruleLists;
 	AddParentRules(ruleLists, GetSelf());

lib/icinga/host.cpp

@@ -155,8 +155,16 @@ void Host::UpdateSlaveServices(void)
 		path.push_back("services");
 		path.push_back(kv.first);
 
+		ExpressionList::Ptr exprl;
+
+		{
+			ObjectLock ilock(item);
+
+			exprl = item->GetLinkedExpressionList();
+		}
+
 		DebugInfo di;
-		item->GetLinkedExpressionList()->FindDebugInfoPath(path, di);
+		exprl->FindDebugInfoPath(path, di);
 
 		if (di.Path.IsEmpty())
 			di = item->GetDebugInfo();
@@ -185,7 +193,7 @@ void Host::UpdateSlaveServices(void)
 
 		/* Clone attributes from the service expression list. */
 		ExpressionList::Ptr svc_exprl = make_shared<ExpressionList>();
-		item->GetLinkedExpressionList()->ExtractPath(path, svc_exprl);
+		exprl->ExtractPath(path, svc_exprl);
 
 		builder->AddExpressionList(svc_exprl);
 

lib/icinga/service-downtime.cpp

@@ -335,8 +335,16 @@ void Service::UpdateSlaveScheduledDowntimes(void)
 		path.push_back("scheduled_downtimes");
 		path.push_back(kv.first);
 
+		ExpressionList::Ptr exprl;
+
+		{
+			ObjectLock ilock(item);
+
+			exprl = item->GetLinkedExpressionList();
+		}
+
 		DebugInfo di;
-		item->GetLinkedExpressionList()->FindDebugInfoPath(path, di);
+		exprl->FindDebugInfoPath(path, di);
 
 		if (di.Path.IsEmpty())
 			di = item->GetDebugInfo();
@@ -361,7 +369,7 @@ void Service::UpdateSlaveScheduledDowntimes(void)
 
 		/* Clone attributes from the scheduled downtime expression list. */
 		ExpressionList::Ptr sd_exprl = make_shared<ExpressionList>();
-		item->GetLinkedExpressionList()->ExtractPath(path, sd_exprl);
+		exprl->ExtractPath(path, sd_exprl);
 
 		builder->AddExpressionList(sd_exprl);
 

lib/icinga/service-notification.cpp

@@ -114,8 +114,16 @@ void Service::UpdateSlaveNotifications(void)
 		path.push_back("notifications");
 		path.push_back(kv.first);
 
+		ExpressionList::Ptr exprl;
+
+		{
+			ObjectLock ilock(exprl);
+
+			exprl = item->GetLinkedExpressionList();
+		}
+
 		DebugInfo di;
-		item->GetLinkedExpressionList()->FindDebugInfoPath(path, di);
+		exprl->FindDebugInfoPath(path, di);
 
 		if (di.Path.IsEmpty())
 			di = item->GetDebugInfo();
@@ -140,7 +148,7 @@ void Service::UpdateSlaveNotifications(void)
 
 		/* Clone attributes from the notification expression list. */
 		ExpressionList::Ptr nfc_exprl = make_shared<ExpressionList>();
-		item->GetLinkedExpressionList()->ExtractPath(path, nfc_exprl);
+		exprl->ExtractPath(path, nfc_exprl);
 
 		builder->AddExpressionList(nfc_exprl);