From 97e63b13199cedd82ee8c1afb9755b744c5432b3 Mon Sep 17 00:00:00 2001
From: Christoph Oelckers <c.oelckers@zdoom.fake>
Date: Thu, 30 Apr 2015 12:53:44 +0200
Subject: [PATCH] - split up FBehavior constructor to better be able to weed
 out broken ACS modules.

Please note that this WILL break old savegames from mods which put ACS sources or unrelated data in the ACS namespace!
---
 src/p_acs.cpp | 38 ++++++++++++++++++++++++++++----------
 src/p_acs.h   |  3 ++-
 2 files changed, 30 insertions(+), 11 deletions(-)

diff --git a/src/p_acs.cpp b/src/p_acs.cpp
index 86674c149..f53eddaf0 100644
--- a/src/p_acs.cpp
+++ b/src/p_acs.cpp
@@ -1409,7 +1409,17 @@ FBehavior *FBehavior::StaticLoadModule (int lumpnum, FileReader *fr, int len)
 		}
 	}
 
-	return new FBehavior (lumpnum, fr, len);
+	FBehavior * behavior = new FBehavior ();
+	if (behavior->Init(lumpnum, fr, len))
+	{
+		return behavior;
+	}
+	else
+	{
+		delete behavior;
+		Printf("%s: invalid ACS module", Wads.GetLumpFullName(lumpnum));
+		return NULL;
+	}
 }
 
 bool FBehavior::StaticCheckAllGood ()
@@ -1668,11 +1678,8 @@ static int ParseLocalArrayChunk(void *chunk, ACSLocalArrays *arrays, int offset)
 	return offset;
 }
 
-FBehavior::FBehavior (int lumpnum, FileReader * fr, int len)
+FBehavior::FBehavior()
 {
-	BYTE *object;
-	int i;
-
 	NumScripts = 0;
 	NumFunctions = 0;
 	NumArrays = 0;
@@ -1684,11 +1691,21 @@ FBehavior::FBehavior (int lumpnum, FileReader * fr, int len)
 	Chunks = NULL;
 	Data = NULL;
 	Format = ACS_Unknown;
-	LumpNum = lumpnum;
+	LumpNum = -1;
 	memset (MapVarStore, 0, sizeof(MapVarStore));
 	ModuleName[0] = 0;
 	FunctionProfileData = NULL;
 
+}
+	
+	
+bool FBehavior::Init(int lumpnum, FileReader * fr, int len)
+{
+	BYTE *object;
+	int i;
+
+	LumpNum = lumpnum;
+
 	// Now that everything is set up, record this module as being among the loaded modules.
 	// We need to do this before resolving any imports, because an import might (indirectly)
 	// need to resolve exports in this module. The only things that can be exported are
@@ -1699,7 +1716,6 @@ FBehavior::FBehavior (int lumpnum, FileReader * fr, int len)
 	// 1. If not, corrupt modules cause memory leaks
 	// 2. Corrupt modules won't be reported when a level is being loaded if this function quits before
 	//    adding it to the list.
-    LibraryID = StaticModules.Push (this) << LIBRARYID_SHIFT;
 
 	if (fr == NULL) len = Wads.LumpLength (lumpnum);
 
@@ -1711,7 +1727,7 @@ FBehavior::FBehavior (int lumpnum, FileReader * fr, int len)
 	// has 24 bytes if it is completely empty. An empty SPTR chunk adds 8 bytes.)
 	if (len < 32)
 	{
-		return;
+		return false;
 	}
 
 	object = new BYTE[len];
@@ -1727,7 +1743,7 @@ FBehavior::FBehavior (int lumpnum, FileReader * fr, int len)
 	if (object[0] != 'A' || object[1] != 'C' || object[2] != 'S')
 	{
 		delete[] object;
-		return;
+		return false;
 	}
 
 	switch (object[3])
@@ -1743,8 +1759,9 @@ FBehavior::FBehavior (int lumpnum, FileReader * fr, int len)
 		break;
 	default:
 		delete[] object;
-		return;
+		return false;
 	}
+    LibraryID = StaticModules.Push (this) << LIBRARYID_SHIFT;
 
 	if (fr == NULL)
 	{
@@ -2135,6 +2152,7 @@ FBehavior::FBehavior (int lumpnum, FileReader * fr, int len)
 	}
 
 	DPrintf ("Loaded %d scripts, %d functions\n", NumScripts, NumFunctions);
+	return true;
 }
 
 FBehavior::~FBehavior ()
diff --git a/src/p_acs.h b/src/p_acs.h
index 88016f0db..d5971e349 100644
--- a/src/p_acs.h
+++ b/src/p_acs.h
@@ -283,8 +283,9 @@ enum ACSFormat { ACS_Old, ACS_Enhanced, ACS_LittleEnhanced, ACS_Unknown };
 class FBehavior
 {
 public:
-	FBehavior (int lumpnum, FileReader * fr=NULL, int len=0);
+	FBehavior ();
 	~FBehavior ();
+	bool Init(int lumpnum, FileReader * fr = NULL, int len = 0);
 
 	bool IsGood ();
 	BYTE *FindChunk (DWORD id) const;