[10833] Avoid use unsafe remove auras in aura apply code.

Specailly example Aura::HandleModCharm code where old code
call RemoveSpellsCausingAura or (a) dead and not called,
or (b) will remove aura self at call.

* Added safe for aura holder context version of RemoveSpellsCausingAura
* Cleanup old simple RemoveSpellsCausingAura code also.

src/game/SpellAuras.cpp

@@ -2930,7 +2930,7 @@ void Aura::HandleAuraModShapeshift(bool apply, bool Real)
         case FORM_MOONKIN:
         {
             // remove movement affects
-            target->RemoveSpellsCausingAura(SPELL_AURA_MOD_ROOT);
+            target->RemoveSpellsCausingAura(SPELL_AURA_MOD_ROOT, GetHolder());
             Unit::AuraList const& slowingAuras = target->GetAurasByType(SPELL_AURA_MOD_DECREASE_SPEED);
             for (Unit::AuraList::const_iterator iter = slowingAuras.begin(); iter != slowingAuras.end();)
             {
@@ -3227,7 +3227,7 @@ void Aura::HandleAuraTransform(bool apply, bool Real)
 
             //dismount polymorphed target (after patch 2.4.2)
             if (target->IsMounted())
-                target->RemoveSpellsCausingAura(SPELL_AURA_MOUNTED);
+                target->RemoveSpellsCausingAura(SPELL_AURA_MOUNTED, GetHolder());
         }
     }
     else
@@ -3639,11 +3639,9 @@ void Aura::HandleModCharm(bool apply, bool Real)
 
     if( apply )
     {
-        if (!target->GetCharmerGuid().IsEmpty())
+        // is it really need after spell check checks?
-        {
+        target->RemoveSpellsCausingAura(SPELL_AURA_MOD_CHARM, GetHolder());
-            target->RemoveSpellsCausingAura(SPELL_AURA_MOD_CHARM);
+        target->RemoveSpellsCausingAura(SPELL_AURA_MOD_POSSESS, GetHolder());
-            target->RemoveSpellsCausingAura(SPELL_AURA_MOD_POSSESS);
-        }
 
         target->SetCharmerGuid(GetCasterGuid());
         target->setFaction(caster->getFaction());

src/game/Unit.cpp

@@ -456,21 +456,26 @@ bool Unit::canReachWithAttack(Unit *pVictim) const
 
 void Unit::RemoveSpellsCausingAura(AuraType auraType)
 {
-    if (auraType >= TOTAL_AURAS) return;
+    for (AuraList::const_iterator iter = m_modAuras[auraType].begin(); iter != m_modAuras[auraType].end();)
-    AuraList::const_iterator iter, next;
-    for (iter = m_modAuras[auraType].begin(); iter != m_modAuras[auraType].end(); iter = next)
     {
-        next = iter;
+        RemoveAurasDueToSpell((*iter)->GetId());
-        ++next;
+        iter = m_modAuras[auraType].begin();
+    }
+}
 
-        if (*iter)
+void Unit::RemoveSpellsCausingAura(AuraType auraType, SpellAuraHolder* except)
+{
+    for (AuraList::const_iterator iter = m_modAuras[auraType].begin(); iter != m_modAuras[auraType].end();)
+    {
+        // skip `except` aura
+        if ((*iter)->GetHolder() == except)
         {
-            RemoveAurasDueToSpell((*iter)->GetId());
+            ++iter;
-            if (!m_modAuras[auraType].empty())
+            continue;
-                next = m_modAuras[auraType].begin();
-            else
-                return;
         }
+
+        RemoveAurasDueToSpell((*iter)->GetId(), except);
+        iter = m_modAuras[auraType].begin();
     }
 }
 

src/game/Unit.h

@@ -1602,6 +1602,7 @@ class MANGOS_DLL_SPEC Unit : public WorldObject
         void RemoveNotOwnSingleTargetAuras(uint32 newPhase = 0x0);
         void RemoveAurasAtMechanicImmunity(uint32 mechMask, uint32 exceptSpellId, bool non_positive = false);
         void RemoveSpellsCausingAura(AuraType auraType);
+        void RemoveSpellsCausingAura(AuraType auraType, SpellAuraHolder* except);
         void RemoveRankAurasDueToSpell(uint32 spellId);
         bool RemoveNoStackAurasDueToAuraHolder(SpellAuraHolder *holder);
         void RemoveAurasWithInterruptFlags(uint32 flags);

src/shared/revision_nr.h

@@ -1,4 +1,4 @@
 #ifndef __REVISION_NR_H__
 #define __REVISION_NR_H__
- #define REVISION_NR "10832"
+ #define REVISION_NR "10833"
 #endif // __REVISION_NR_H__