From 141c1a985408cebd3ecd3d636d14f869c7f0be5b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Micha=C5=82=20W=2E=20Urba=C5=84czyk?= <mwu-tow@gazeta.pl>
Date: Sat, 7 Sep 2013 16:57:31 +0000
Subject: [PATCH] Not crash when asking callback about requirements for not
 existing building, fixing #1444 corrupted saves (for testing).

---
 lib/CTownHandler.h    | 9 +++++++++
 lib/IGameCallback.cpp | 6 ++++--
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/lib/CTownHandler.h b/lib/CTownHandler.h
index 29623fb4e..73b766a8e 100644
--- a/lib/CTownHandler.h
+++ b/lib/CTownHandler.h
@@ -198,6 +198,15 @@ public:
 	{
 		h & names & faction & creatures & dwellings & dwellingNames & buildings & hordeLvl & mageLevel
 			& primaryRes & warMachine & clientInfo & moatDamage;
+
+		//Fix #1444 corrupted save
+		while(auto badElem = vstd::tryFindIf(buildings, [](const std::pair<BuildingID, ConstTransitivePtr<CBuilding>> &building)
+														{ return building.second == nullptr; }))
+		{
+			std::cout << "#1444-like bug encountered, fixing buildings list by removing bogus entry " << badElem->first << " from " << faction->name << std::endl;
+			buildings.erase(badElem->first);
+		}
+
 	}
 };
 
diff --git a/lib/IGameCallback.cpp b/lib/IGameCallback.cpp
index cafd91ed6..7929982c8 100644
--- a/lib/IGameCallback.cpp
+++ b/lib/IGameCallback.cpp
@@ -567,10 +567,11 @@ EBuildingState::EBuildingState CGameInfoCallback::canBuildStructure( const CGTow
 {
 	ERROR_RET_VAL_IF(!canGetFullInfo(t), "Town is not owned!", EBuildingState::TOWN_NOT_OWNED);
 
+	if(!t->town->buildings.count(ID))
+		return EBuildingState::BUILDING_ERROR;
+
 	const CBuilding * pom = t->town->buildings[ID];
 
-	if(!pom)
-		return EBuildingState::BUILDING_ERROR;
 
 	if(t->hasBuilt(ID))	//already built
 		return EBuildingState::ALREADY_PRESENT;
@@ -632,6 +633,7 @@ EBuildingState::EBuildingState CGameInfoCallback::canBuildStructure( const CGTow
 std::set<BuildingID> CGameInfoCallback::getBuildingRequiments( const CGTownInstance *t, BuildingID ID )
 {
 	ERROR_RET_VAL_IF(!canGetFullInfo(t), "Town is not owned!", std::set<BuildingID>());
+	ERROR_RET_VAL_IF(!t->town->buildings.count(ID), "No such building!", std::set<BuildingID>());
 
 	std::set<int> used;
 	used.insert(ID);