Fix race condition on Intercept

* `RequestImmediateCancelEffect` now returns whether the effect was removed or not, which is thread safe and allows the caller to react appropriately.
OpenDAoC · Aug 4, 2024 · 128927b · 128927b
1 parent dbecf30
commit 128927b
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Showing 2 changed files with 14 additions and 11 deletions.
diff --git a/GameServer/ECS-Components/AttackComponent.cs b/GameServer/ECS-Components/AttackComponent.cs
@@ -2083,12 +2083,13 @@ public virtual eAttackResult CalculateEnemyAttackResult(WeaponAction action, Att
 
             if (intercept != null && !stealthStyle)
             {
-                ad.Target = intercept.Source;
-
-                if (intercept.Source is GamePlayer)
-                    EffectService.RequestCancelEffect(intercept);
+                if (intercept.Source is not GamePlayer || EffectService.RequestImmediateCancelEffect(intercept))
+                {
+                    ad.Target = intercept.Source;
+                    return eAttackResult.HitUnstyled;
+                }
 
-                return eAttackResult.HitUnstyled;
+                intercept = null;
             }
 
             if (!defenseDisabled)

diff --git a/GameServer/ECS-Services/EffectService.cs b/GameServer/ECS-Services/EffectService.cs
@@ -195,10 +195,10 @@ private static void UpdateEffectIcons(ECSGameEffect e)
             }
         }
 
-        private static void HandleCancelEffect(ECSGameEffect e)
+        private static bool HandleCancelEffect(ECSGameEffect e)
         {
             if (!e.Owner.effectListComponent.RemoveEffect(e))
-                return;
+                return false;
 
             if (e is ECSGameSpellEffect spellEffect)
             {
@@ -258,6 +258,8 @@ private static void HandleCancelEffect(ECSGameEffect e)
             }
             else if (e.Owner is GameNPC npc && npc.Brain is IControlledBrain npcBrain)
                 npcBrain.UpdatePetWindow();
+
+            return true;
         }
 
         /// <summary>
@@ -305,24 +307,24 @@ public static void RequestCancelConcEffect(IConcentrationEffect concEffect, bool
         /// <summary>
         /// Immediately removes an ECSGameEffect.
         /// </summary>
-        public static void RequestImmediateCancelEffect(ECSGameEffect effect, bool playerCanceled = false)
+        public static bool RequestImmediateCancelEffect(ECSGameEffect effect, bool playerCanceled = false)
         {
             if (effect is null)
-                return;
+                return false;
 
             // Player can't remove negative effect or Effect in Immunity State
             if (playerCanceled && ((!effect.HasPositiveEffect) || effect is ECSImmunityEffect))
             {
                 if (effect.Owner is GamePlayer player)
                     player.Out.SendMessage(LanguageMgr.GetTranslation((effect.Owner as GamePlayer).Client, "Effects.GameSpellEffect.CantRemoveEffect"), eChatType.CT_System, eChatLoc.CL_SystemWindow);
 
-                return;
+                return false;
             }
 
             // playerCanceled param isn't used but it's there in case we eventually want to...
             effect.CancelEffect = true;
             effect.ExpireTick = GameLoop.GameLoopTime - 1;
-            HandleCancelEffect(effect);
+            return HandleCancelEffect(effect);
         }
 
         /// <summary>