Added Fl_Widget_Tracker in handle() methods etc. to avoid accessing widgets

after deletion (STR #1306). This is all I could find, but maybe there are
more places in the code.


git-svn-id: file:///fltk/svn/fltk/branches/branch-1.3@7115 ea41ed52-d2ee-0310-a9c1-e6b18d33e121

12 files changed, 149 insertions, 58 deletions

diff --git a/FL/Fl_Input_Choice.H b/FL/Fl_Input_Choice.H
index a5d025523..0010ea336 100644
--- a/FL/Fl_Input_Choice.H
+++ b/FL/Fl_Input_Choice.H
@@ -76,6 +76,7 @@ class Fl_Input_Choice : public Fl_Group {
 
   static void menu_cb(Fl_Widget*, void *data) { 
     Fl_Input_Choice *o=(Fl_Input_Choice *)data;
+    Fl_Widget_Tracker wp(o);
     const Fl_Menu_Item *item = o->menubutton()->mvalue();
     if (item && item->flags & (FL_SUBMENU|FL_SUBMENU_POINTER)) return;	// ignore submenus
     if (!strcmp(o->inp_->value(), o->menu_->text()))
@@ -92,6 +93,8 @@ class Fl_Input_Choice : public Fl_Group {
       if (o->when() & (FL_WHEN_CHANGED|FL_WHEN_RELEASE))
 	o->do_callback();
     }
+    
+    if (wp.deleted()) return;
 
     if (o->callback() != default_callback)
     {
@@ -102,6 +105,7 @@ class Fl_Input_Choice : public Fl_Group {
 
   static void inp_cb(Fl_Widget*, void *data) { 
     Fl_Input_Choice *o=(Fl_Input_Choice *)data;
+    Fl_Widget_Tracker wp(o);
     if (o->inp_->changed()) {
       o->Fl_Widget::set_changed();
       if (o->when() & (FL_WHEN_CHANGED|FL_WHEN_RELEASE))
@@ -111,6 +115,8 @@ class Fl_Input_Choice : public Fl_Group {
       if (o->when() & FL_WHEN_NOT_CHANGED)
 	o->do_callback();
     }
+    
+    if (wp.deleted()) return;
 
     if (o->callback() != default_callback)
       o->Fl_Widget::clear_changed();
diff --git a/src/Fl.cxx b/src/Fl.cxx
index c8b359c6b..9670e29c2 100644
--- a/src/Fl.cxx
+++ b/src/Fl.cxx
@@ -44,9 +44,9 @@
 #import <Cocoa/Cocoa.h>
 #endif
 
-#ifdef DEBUG
+#if defined(DEBUG) || defined(DEBUG_WATCH)
 #  include <stdio.h>
-#endif // DEBUG
+#endif // DEBUG || DEBUG_WATCH
 
 #ifdef WIN32
 #  include <ole2.h>
@@ -1648,11 +1648,11 @@ void Fl::watch_widget_pointer(Fl_Widget *&w)
     widget_watch = (Fl_Widget***)realloc(widget_watch, sizeof(Fl_Widget**)*max_widget_watch);
   }
   widget_watch[num_widget_watch++] = wp;
-#ifdef DEBUG
+#ifdef DEBUG_WATCH
   printf ("\nwatch_widget_pointer:   (%d/%d) %8p => %8p\n",
     num_widget_watch,num_widget_watch,wp,*wp);
   fflush(stdout);
-#endif // DEBUG
+#endif // DEBUG_WATCH
 }
 
 /**
@@ -1674,18 +1674,18 @@ void Fl::release_widget_pointer(Fl_Widget *&w)
       if (j<i) widget_watch[j] = widget_watch[i]; // fill gap
       j++;
     }
-#ifdef DEBUG
+#ifdef DEBUG_WATCH
     else { // found widget pointer
       printf ("release_widget_pointer: (%d/%d) %8p => %8p\n",
 	i+1,num_widget_watch,wp,*wp);
     }
-#endif //DEBUG
+#endif //DEBUG_WATCH
   }
   num_widget_watch = j;
-#ifdef DEBUG
+#ifdef DEBUG_WATCH
   printf ("                        num_widget_watch = %d\n\n",num_widget_watch);
   fflush(stdout);
-#endif // DEBUG
+#endif // DEBUG_WATCH
   return;
 }
 /**
diff --git a/src/Fl_Adjuster.cxx b/src/Fl_Adjuster.cxx
index 6a7d06060..4f14c7a39 100644
--- a/src/Fl_Adjuster.cxx
+++ b/src/Fl_Adjuster.cxx
@@ -69,6 +69,7 @@ int Fl_Adjuster::handle(int event) {
   double v;
   int delta;
   int mx = Fl::event_x();
+  // Fl_Widget_Tracker wp(this);
   switch (event) {
     case FL_PUSH:
       if (Fl::visible_focus()) Fl::focus(this);
@@ -77,7 +78,10 @@ int Fl_Adjuster::handle(int event) {
 	drag = 3*(mx-x())/w() + 1;
       else
 	drag = 3-3*(Fl::event_y()-y()-1)/h();
-      handle_push();
+      { Fl_Widget_Tracker wp(this);
+	handle_push();
+	if (wp.deleted()) return 1;
+      }
       redraw();
       return 1;
     case FL_DRAG:
@@ -98,9 +102,9 @@ int Fl_Adjuster::handle(int event) {
 	  delta = 0;
       }
       switch (drag) {
-      case 3: v = increment(previous_value(), delta); break;
-      case 2: v = increment(previous_value(), delta*10); break;
-      default:v = increment(previous_value(), delta*100); break;
+	case 3: v = increment(previous_value(), delta); break;
+	case 2: v = increment(previous_value(), delta*10); break;
+	default:v = increment(previous_value(), delta*100); break;
       }
       handle_drag(soft() ? softclamp(v) : clamp(v));
       return 1;
@@ -109,11 +113,13 @@ int Fl_Adjuster::handle(int event) {
 	if (Fl::event_state()&0xF0000) delta = -10;
 	else delta = 10;
 	switch (drag) {
-	case 3: v = increment(previous_value(), delta); break;
-	case 2: v = increment(previous_value(), delta*10); break;
-	default:v = increment(previous_value(), delta*100); break;
+	  case 3: v = increment(previous_value(), delta); break;
+	  case 2: v = increment(previous_value(), delta*10); break;
+	  default:v = increment(previous_value(), delta*100); break;
 	}
+	Fl_Widget_Tracker wp(this);
 	handle_drag(soft() ? softclamp(v) : clamp(v));
+	if (wp.deleted()) return 1;
       }
       drag = 0;
       redraw();
diff --git a/src/Fl_Browser_.cxx b/src/Fl_Browser_.cxx
index 2a654dbe5..ad98f858f 100644
--- a/src/Fl_Browser_.cxx
+++ b/src/Fl_Browser_.cxx
@@ -678,11 +678,15 @@ int Fl_Browser_::deselect(int docallbacks) {
 int Fl_Browser_::select_only(void* item, int docallbacks) {
   if (!item) return deselect(docallbacks);
   int change = 0;
+  Fl_Widget_Tracker wp(this);
   if (type() == FL_MULTI_BROWSER) {
-    for (void* p = item_first(); p; p = item_next(p))
+    for (void* p = item_first(); p; p = item_next(p)) {
       if (p != item) change |= select(p, 0, docallbacks);
+      if (wp.deleted()) return change;
+    }
   }
   change |= select(item, 1, docallbacks);
+  if (wp.deleted()) return change;
   display(item);
   return change;
 }
@@ -693,6 +697,20 @@ int Fl_Browser_::select_only(void* item, int docallbacks) {
   \returns 1 if event was processed, 0 if not.
 */
 int Fl_Browser_::handle(int event) {
+
+  // NOTE:
+  // We use Fl_Widget_Tracker to test if the user has deleted
+  // this widget in a callback. Callbacks can be called by:
+  //  - do_callback()
+  //  - select()
+  //  - select_only()
+  //  - deselect()
+  // Thus we must test wp.deleted() after each of these calls,
+  // unless we return directly after one of these.
+  // If wp.deleted() is true, we return 1 because we used the event.
+
+  Fl_Widget_Tracker wp(this);
+
   // must do shortcuts first or the scrollbar will get them...
   if (event == FL_ENTER || event == FL_LEAVE) return 1;
   if (event == FL_KEYBOARD && type() >= FL_HOLD_BROWSER) {
@@ -706,8 +724,12 @@ int Fl_Browser_::handle(int event) {
             if (item_height(l)>0) {select_only(l, when()); break;}
             return 1;
         case FL_Up:
-          while ((l = item_prev(l))) if (item_height(l)>0) {
-            select_only(l, when()); break;}
+          while ((l = item_prev(l))) {
+	    if (item_height(l)>0) {
+	      select_only(l, when());
+	      break; // no need to test wp (return 1)
+	    }
+	  }
           return 1;
         } 
       } else  {
@@ -715,6 +737,7 @@ int Fl_Browser_::handle(int event) {
         case FL_Enter:
         case FL_KP_Enter:
           select_only(l, when() & ~FL_WHEN_ENTER_KEY);
+	  if (wp.deleted()) return 1;
 	  if (when() & FL_WHEN_ENTER_KEY) {
 	    set_changed();
 	    do_callback();
@@ -728,6 +751,7 @@ int Fl_Browser_::handle(int event) {
           while ((l = item_next(l))) {
             if (Fl::event_state(FL_SHIFT|FL_CTRL))
               select(l, l1 ? item_selected(l1) : 1, when());
+	    if (wp.deleted()) return 1;
             if (item_height(l)>0) goto J1;
           }
           return 1;
@@ -735,6 +759,7 @@ int Fl_Browser_::handle(int event) {
           while ((l = item_prev(l))) {
             if (Fl::event_state(FL_SHIFT|FL_CTRL))
               select(l, l1 ? item_selected(l1) : 1, when());
+	    if (wp.deleted()) return 1;
             if (item_height(l)>0) goto J1;
           }
           return 1;
@@ -749,6 +774,8 @@ J1:
   }
   
   if (Fl_Group::handle(event)) return 1;
+  if (wp.deleted()) return 1;
+
   int X, Y, W, H; bbox(X, Y, W, H);
   int my;
 // NOTE:
@@ -784,9 +811,11 @@ J1:
       ;
     else if (type() != FL_MULTI_BROWSER) {
       change = select_only(find_item(my), 0);
+      if (wp.deleted()) return 1;
       if (change && (when() & FL_WHEN_CHANGED)) {
 	set_changed();
 	do_callback();
+	if (wp.deleted()) return 1;
       }
     } else {
       void* l = find_item(my);
@@ -796,9 +825,11 @@ J1:
 	if (l) {
 	  whichway = !item_selected(l);
 	  change = select(l, whichway, 0);
+	  if (wp.deleted()) return 1;
 	  if (change && (when() & FL_WHEN_CHANGED)) {
 	    set_changed();
 	    do_callback();
+	    if (wp.deleted()) return 1;
 	  }
 	}
       } else if (Fl::event_state(FL_SHIFT)) { // extend selection:
@@ -814,23 +845,29 @@ J1:
 	  if (!m) {down = 0; break;}
 	}}
 	if (down) {
-	  for (void* m = selection_; m != l; m = item_next(m))
+	  for (void* m = selection_; m != l; m = item_next(m)) {
 	    select(m, whichway, when() & FL_WHEN_CHANGED);
+	    if (wp.deleted()) return 1;
+	  }
 	} else {
 	  void* e = selection_;
 	  for (void* m = item_next(l); m; m = item_next(m)) {
 	    select(m, whichway, when() & FL_WHEN_CHANGED);
+	    if (wp.deleted()) return 1;
 	    if (m == e) break;
 	  }
 	}
 	// do the clicked item last so the select box is around it:
 	change = 1;
 	if (l) select(l, whichway, when() & FL_WHEN_CHANGED);
+	if (wp.deleted()) return 1;
       } else { // select only this item
 	change = select_only(l, 0);
+	if (wp.deleted()) return 1;
 	if (change && (when() & FL_WHEN_CHANGED)) {
 	  set_changed();
 	  do_callback();
+	  if (wp.deleted()) return 1;
 	}
       }
     }
@@ -863,10 +900,12 @@ J1:
       for (; t && t != b; t = item_next(t)) {
 	char change_t;
 	change_t = select(t, whichway, 0);
+	if (wp.deleted()) return 1;
 	change |= change_t;
 	if (change_t && (when() & FL_WHEN_CHANGED)) {
 	  set_changed();
 	  do_callback();
+	  if (wp.deleted()) return 1;
 	}
       }
       if (l) selection_ = l;
@@ -877,12 +916,16 @@ J1:
 	find_item(my);
       change = (l != l1);
       select_only(l, when() & FL_WHEN_CHANGED);
+      if (wp.deleted()) return 1;
     }
     py = my;
     return 1;
   case FL_RELEASE:
     if (type() == FL_SELECT_BROWSER) {
-      void* t = selection_; deselect(); selection_ = t;
+      void* t = selection_;
+      deselect();
+      if (wp.deleted()) return 1;
+      selection_ = t;
     }
     if (change) {
       set_changed();
@@ -890,7 +933,8 @@ J1:
     } else {
       if (when() & FL_WHEN_NOT_CHANGED) do_callback();
     }
-    
+    if (wp.deleted()) return 1;
+
     // double click calls the callback: (like Enter Key)
     if (Fl::event_clicks() && (when() & FL_WHEN_ENTER_KEY)) {
       set_changed();
diff --git a/src/Fl_Button.cxx b/src/Fl_Button.cxx
index c32075999..147e5cf4d 100644
--- a/src/Fl_Button.cxx
+++ b/src/Fl_Button.cxx
@@ -117,7 +117,11 @@ int Fl_Button::handle(int event) {
     else {
       value(oldval);
       set_changed();
-      if (when() & FL_WHEN_CHANGED) do_callback();
+      if (when() & FL_WHEN_CHANGED) {
+	Fl_Widget_Tracker wp(this);
+        do_callback();
+        if (wp.deleted()) return 1;
+      }
     }
     if (when() & FL_WHEN_RELEASE) do_callback();
     return 1;
@@ -156,6 +160,7 @@ int Fl_Button::handle(int event) {
     if (Fl::focus() == this && Fl::event_key() == ' ' &&
         !(Fl::event_state() & (FL_SHIFT | FL_CTRL | FL_ALT | FL_META))) {
       set_changed();
+      Fl_Widget_Tracker wp(this);
       if (type() == FL_RADIO_BUTTON && !value_) {
 	setonly();
 	if (when() & FL_WHEN_CHANGED) do_callback();
@@ -163,6 +168,7 @@ int Fl_Button::handle(int event) {
 	value(!value());
 	if (when() & FL_WHEN_CHANGED) do_callback();
       }
+      if (wp.deleted()) return 1;
       if (when() & FL_WHEN_RELEASE) do_callback();
       return 1;
     }
diff --git a/src/Fl_Counter.cxx b/src/Fl_Counter.cxx
index b77fc8a4c..de83f15d5 100644
--- a/src/Fl_Counter.cxx
+++ b/src/Fl_Counter.cxx
@@ -137,14 +137,19 @@ int Fl_Counter::handle(int event) {
     return 1;
   case FL_PUSH:
     if (Fl::visible_focus()) Fl::focus(this);
-    handle_push();
+    { Fl_Widget_Tracker wp(this);
+      handle_push();
+      if (wp.deleted()) return 1;
+    }
   case FL_DRAG:
     i = calc_mouseobj();
     if (i != mouseobj) {
       Fl::remove_timeout(repeat_callback, this);
       mouseobj = (uchar)i;
       if (i) Fl::add_timeout(INITIALREPEAT, repeat_callback, this);
+      Fl_Widget_Tracker wp(this);
       increment_cb();
+      if (wp.deleted()) return 1;
       redraw();
     }
     return 1;
diff --git a/src/Fl_Dial.cxx b/src/Fl_Dial.cxx
index f91b55df9..fed278ca3 100644
--- a/src/Fl_Dial.cxx
+++ b/src/Fl_Dial.cxx
@@ -109,8 +109,10 @@ void Fl_Dial::draw() {
 */
 int Fl_Dial::handle(int event, int X, int Y, int W, int H) {
   switch (event) {
-  case FL_PUSH:
+  case FL_PUSH: {
+    Fl_Widget_Tracker wp(this);  
     handle_push();
+    if (wp.deleted()) return 1; }
   case FL_DRAG: {
     int mx = (Fl::event_x()-X-W/2)*H;
     int my = (Fl::event_y()-Y-H/2)*W;
diff --git a/src/Fl_File_Input.cxx b/src/Fl_File_Input.cxx
index efd2d062e..8faf8b0bd 100644
--- a/src/Fl_File_Input.cxx
+++ b/src/Fl_File_Input.cxx
@@ -215,9 +215,12 @@ Fl_File_Input::handle(int event) 		// I - Event
         return Fl_Input::handle(event);
 
     default :
-      if (Fl_Input::handle(event)) {
-	damage(FL_DAMAGE_BAR);
-	return 1;
+      { Fl_Widget_Tracker wp(this);
+	if (Fl_Input::handle(event)) {
+	  if (wp.exists())
+	    damage(FL_DAMAGE_BAR);
+	  return 1;
+	}
       }
       return 0;
   }
diff --git a/src/Fl_Group.cxx b/src/Fl_Group.cxx
index b42f1caf8..4deba31ce 100644
--- a/src/Fl_Group.cxx
+++ b/src/Fl_Group.cxx
@@ -227,8 +227,9 @@ int Fl_Group::handle(int event) {
     for (i = children(); i--;) {
       o = a[i];
       if (o->takesevents() && Fl::event_inside(o)) {
+	Fl_Widget_Tracker wp(o);
 	if (send(o,FL_PUSH)) {
-	  if (Fl::pushed() && !o->contains(Fl::pushed())) Fl::pushed(o);
+	  if (Fl::pushed() && wp.exists() && !o->contains(Fl::pushed())) Fl::pushed(o);
 	  return 1;
 	}
       }
diff --git a/src/Fl_Slider.cxx b/src/Fl_Slider.cxx
index 93a4457fd..6b2a328d1 100644
--- a/src/Fl_Slider.cxx
+++ b/src/Fl_Slider.cxx
@@ -222,10 +222,14 @@ void Fl_Slider::draw() {
 }
 
 int Fl_Slider::handle(int event, int X, int Y, int W, int H) {
+  // Fl_Widget_Tracker wp(this);
   switch (event) {
-  case FL_PUSH:
+  case FL_PUSH: {
+    Fl_Widget_Tracker wp(this);
     if (!Fl::event_inside(X, Y, W, H)) return 0;
     handle_push();
+    if (wp.deleted()) return 1; }
+    // fall through ...
   case FL_DRAG: {
 
     double val;
@@ -293,34 +297,44 @@ int Fl_Slider::handle(int event, int X, int Y, int W, int H) {
   case FL_RELEASE:
     handle_release();
     return 1;
-  case FL_KEYBOARD :
-    switch (Fl::event_key()) {
-      case FL_Up:
-        if (horizontal()) return 0;
-        handle_push();
-	handle_drag(clamp(increment(value(),-1)));
-	handle_release();
-	return 1;
-      case FL_Down:
-        if (horizontal()) return 0;
-        handle_push();
-	handle_drag(clamp(increment(value(),1)));
-	handle_release();
-	return 1;
-      case FL_Left:
-        if (!horizontal()) return 0;
-        handle_push();
-	handle_drag(clamp(increment(value(),-1)));
-	handle_release();
-	return 1;
-      case FL_Right:
-        if (!horizontal()) return 0;
-        handle_push();
-	handle_drag(clamp(increment(value(),1)));
-	handle_release();
-	return 1;
-      default:
-        return 0;
+  case FL_KEYBOARD:
+    { Fl_Widget_Tracker wp(this);
+      switch (Fl::event_key()) {
+	case FL_Up:
+	  if (horizontal()) return 0;
+	  handle_push();
+	  if (wp.deleted()) return 1;
+	  handle_drag(clamp(increment(value(),-1)));
+	  if (wp.deleted()) return 1;
+	  handle_release();
+	  return 1;
+	case FL_Down:
+	  if (horizontal()) return 0;
+	  handle_push();
+	  if (wp.deleted()) return 1;
+	  handle_drag(clamp(increment(value(),1)));
+	  if (wp.deleted()) return 1;
+	  handle_release();
+	  return 1;
+	case FL_Left:
+	  if (!horizontal()) return 0;
+	  handle_push();
+	  if (wp.deleted()) return 1;
+	  handle_drag(clamp(increment(value(),-1)));
+	  if (wp.deleted()) return 1;
+	  handle_release();
+	  return 1;
+	case FL_Right:
+	  if (!horizontal()) return 0;
+	  handle_push();
+	  if (wp.deleted()) return 1;
+	  handle_drag(clamp(increment(value(),1)));
+	  if (wp.deleted()) return 1;
+	  handle_release();
+	  return 1;
+	default:
+	  return 0;
+      }
     }
     // break not required because of switch...
   case FL_FOCUS :
diff --git a/src/Fl_Tabs.cxx b/src/Fl_Tabs.cxx
index 41de89a7e..e36a4cbda 100644
--- a/src/Fl_Tabs.cxx
+++ b/src/Fl_Tabs.cxx
@@ -161,8 +161,10 @@ int Fl_Tabs::handle(int event) {
         redraw_tabs();
       }
       if (o && value(o)) {
+        Fl_Widget_Tracker wp(o);
         set_changed();
 	do_callback();
+	if (wp.deleted()) return 1;
       }
       Fl_Tooltip::current(o);
     } else {
diff --git a/src/Fl_Value_Input.cxx b/src/Fl_Value_Input.cxx
index 60f204eb4..7b804225d 100644
--- a/src/Fl_Value_Input.cxx
+++ b/src/Fl_Value_Input.cxx
@@ -100,8 +100,10 @@ int Fl_Value_Input::handle(int event) {
     if (value() != previous_value() || !Fl::event_is_click())
       handle_release();
     else {
+      Fl_Widget_Tracker wp(&input);
       input.handle(FL_PUSH);
-      input.handle(FL_RELEASE);
+      if (wp.exists())
+	input.handle(FL_RELEASE);
     }
     return 1;
   case FL_FOCUS: