From 4f881b9e26131b2cd259337bf81c89104b349c46 Mon Sep 17 00:00:00 2001
From: Misa <infoteddy@infoteddy.info>
Date: Thu, 19 Aug 2021 16:36:31 -0700
Subject: [PATCH] Fix enemy movement types 10/12 causing memory leaks

If spawned as a custom enemy (createentity entry 56), or spawned outside
of the rooms they spawn in in the main game, they will repeatedly clone
themselves every frame, which profusely leaks memory. In fact it quickly
causes a crash in 2.2 and previous, but 2.3 fixes that crash, so it just
keeps spawning enemies endlessly, which eventually lags the game, and
eventually can out-of-memory your system (bad!).

The problem is those movement types rely on entclass::setenemyroom() to
change their `behave` to be 11 or 13. Else, the new entity created will
still have `behave` 10 or 12, which will create ANOTHER entity in the
same way, and so on, and so forth.

So to fix this, just make it so if an enemy is still `behave` 10 or 12
by the end, then, just set it to -1. That way it'll stay still and won't
cause any harm.

I considered setting the `behave` to 11 or 13 respectively, but, that's
probably going farther than just fixing a memory leak, and anyways, it's
not that much useful for me as a custom level maker, and the entities
spawned aren't really controllable.
---
 desktop_version/src/Entity.cpp | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/desktop_version/src/Entity.cpp b/desktop_version/src/Entity.cpp
index 5ca6c9f9..a9cd394d 100644
--- a/desktop_version/src/Entity.cpp
+++ b/desktop_version/src/Entity.cpp
@@ -1204,6 +1204,15 @@ int entityclass::crewcolour( int t )
     return 0;
 }
 
+static void entityclonefix(entclass* entity)
+{
+    if (entity->behave == 10 || entity->behave == 12)
+    {
+        /* Fix memory leak */
+        entity->behave = -1;
+    }
+}
+
 void entityclass::createentity(int xp, int yp, int t, int meta1, int meta2, int p1, int p2, int p3, int p4)
 {
     k = entities.size();
@@ -1324,6 +1333,7 @@ void entityclass::createentity(int xp, int yp, int t, int meta1, int meta2, int
         else
         {
             entity.setenemyroom(game.roomx, game.roomy);
+            entityclonefix(&entity);
         }
         break;
     case 2: //A moving platform
@@ -2094,6 +2104,7 @@ void entityclass::createentity(int xp, int yp, int t, int meta1, int meta2, int
           entity.colour = 18;
         }
 
+        entityclonefix(&entity);
         break;
     }