From 18a378139f8cbb58924e93f012b1445a1328e38f Mon Sep 17 00:00:00 2001
From: Christoph Sommer <mail@christoph-sommer.de>
Date: Mon, 5 Feb 2007 20:41:23 +0000
Subject: [PATCH] Fixed nasty bug with remove_listener hooks

SVN-Revision: 4814
---
 src/game_object.cpp          | 34 +++++++++++++++++++++++++++++++++-
 src/game_object.hpp          | 15 +++++++--------
 src/trigger/trigger_base.cpp | 27 +++++++++++++++++++++------
 src/trigger/trigger_base.hpp |  2 +-
 4 files changed, 62 insertions(+), 16 deletions(-)

diff --git a/src/game_object.cpp b/src/game_object.cpp
index 1faa7bd3f..273367f6e 100644
--- a/src/game_object.cpp
+++ b/src/game_object.cpp
@@ -18,7 +18,7 @@
 //  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 
 #include <config.h>
-
+#include "log.hpp"
 #include "game_object.hpp"
 #include "object_remove_listener.hpp"
 
@@ -38,3 +38,35 @@ GameObject::~GameObject()
     entry = next;
   }
 }
+
+ 
+void 
+GameObject::add_remove_listener(ObjectRemoveListener* listener)
+{
+  RemoveListenerListEntry* entry = new RemoveListenerListEntry();
+  entry->next = remove_listeners;
+  entry->listener = listener;
+  remove_listeners = entry;
+}
+
+void
+GameObject::del_remove_listener(ObjectRemoveListener* listener)
+{
+  RemoveListenerListEntry* entry = remove_listeners;
+  if (entry->listener == listener) {
+    remove_listeners = entry->next;
+    delete entry;
+    return;
+  }
+  RemoveListenerListEntry* next = entry->next;
+  while(next != NULL) {
+    if (next->listener == listener) {
+      entry->next = next->next;
+      delete next;
+      break;
+    }
+    entry = next;
+    next = next->next;
+  }
+}
+
diff --git a/src/game_object.hpp b/src/game_object.hpp
index f463f88d4..22aa3a6ad 100644
--- a/src/game_object.hpp
+++ b/src/game_object.hpp
@@ -69,14 +69,13 @@ public:
   /** registers a remove listener which will be called if the object
    * gets removed/destroyed
    */
-  void add_remove_listener(ObjectRemoveListener* listener)
-  {
-    RemoveListenerListEntry* entry = new RemoveListenerListEntry();
-    entry->next = remove_listeners;
-    entry->listener = listener;
-
-    remove_listeners = entry;
-  }
+  void add_remove_listener(ObjectRemoveListener* listener);
+  
+  /** 
+   * unregisters a remove listener, so it will no longer be called if the object
+   * gets removed/destroyed
+   */
+  void del_remove_listener(ObjectRemoveListener* listener);
 
   const std::string& get_name() const
   {
diff --git a/src/trigger/trigger_base.cpp b/src/trigger/trigger_base.cpp
index 47e09c532..a221b2998 100644
--- a/src/trigger/trigger_base.cpp
+++ b/src/trigger/trigger_base.cpp
@@ -22,25 +22,34 @@
 #include "trigger_base.hpp"
 #include "video/drawing_context.hpp"
 #include "object/player.hpp"
+#include "log.hpp"
 
 TriggerBase::TriggerBase()
-  : sprite(0), lasthit(false), hit(false), losetouch_listener(0)
+  : sprite(0), lasthit(false), hit(false)
 {
   set_group(COLGROUP_TOUCHABLE);
 }
 
 TriggerBase::~TriggerBase()
 {
+  // unregister remove_listener hooks, so nobody will try to call us after we've been destroyed
+  for (std::list<Player*>::iterator i = losetouch_listeners.begin(); i != losetouch_listeners.end(); i++) {
+    Player* p = *i;
+    p->del_remove_listener(this);
+  }
+  losetouch_listeners.clear();
 }
 
 void
 TriggerBase::update(float )
 {
   if (lasthit && !hit) {
-    if (losetouch_listener) {
-      event(*losetouch_listener, EVENT_LOSETOUCH);
-      losetouch_listener = 0;
+    for (std::list<Player*>::iterator i = losetouch_listeners.begin(); i != losetouch_listeners.end(); i++) {
+      Player* p = *i;
+      event(*p, EVENT_LOSETOUCH);
+      p->del_remove_listener(this);
     }
+    losetouch_listeners.clear();
   }
   lasthit = hit;
   hit = false;
@@ -62,7 +71,7 @@ TriggerBase::collision(GameObject& other, const CollisionHit& )
   if(player) {
     hit = true;
     if(!lasthit) {
-      losetouch_listener = player;
+      losetouch_listeners.push_back(player);
       player->add_remove_listener(this);
       event(*player, EVENT_TOUCH);
     }
@@ -74,6 +83,12 @@ TriggerBase::collision(GameObject& other, const CollisionHit& )
 void 
 TriggerBase::object_removed(GameObject* object)
 {
-  if (losetouch_listener == object) losetouch_listener = 0;
+  for (std::list<Player*>::iterator i = losetouch_listeners.begin(); i != losetouch_listeners.end(); i++) {
+    Player* p = *i;
+    if (p == object) {
+      losetouch_listeners.erase(i);
+      break;
+    }
+  }
 }
 
diff --git a/src/trigger/trigger_base.hpp b/src/trigger/trigger_base.hpp
index d03d85b08..571dac5b0 100644
--- a/src/trigger/trigger_base.hpp
+++ b/src/trigger/trigger_base.hpp
@@ -62,7 +62,7 @@ private:
   bool lasthit;
   bool hit;
 
-  Player* losetouch_listener; /**< Player that will be informed when we lose touch with him */
+  std::list<Player*> losetouch_listeners; /**< Players that will be informed when we lose touch with them */
 };
 
 #endif /*SUPERTUX_INTERACTIVE_OBJECT_H*/
-- 
2.11.0