FObject double free prevention of fc::empty_string

ChangeLog

@@ -1,3 +1,6 @@
+2017-10-15  Markus Gans  <guru.mail@muenster.de>
+	* FObject double free prevention of fc::empty_string
+
 2017-10-14  Markus Gans  <guru.mail@muenster.de>
 	* Fixed a bug in the FObject check of parent objects
 	* Replace the deprecated readdir_r function (CVE-2013-4237)

examples/listview.cpp

@@ -182,11 +182,11 @@ void Listview::cb_showInMessagebox (FWidget* widget, data_ptr)
 {
   FListView* listView = static_cast<FListView*>(widget);
   FListViewItem* item = listView->getCurrentItem();
-  FMessageBox info ( "Weather in " + item->getText(0)
+  FMessageBox info ( "Weather in " + item->getText(1)
-                   , "  Condition: " + item->getText(1) + "\n"
+                   , "  Condition: " + item->getText(2) + "\n"
-                     "Temperature: " + item->getText(2) + "\n"
+                     "Temperature: " + item->getText(3) + "\n"
-                     "   Humidity: " + item->getText(3) + "\n"
+                     "   Humidity: " + item->getText(4) + "\n"
-                     "   Pressure: " + item->getText(4)
+                     "   Pressure: " + item->getText(5)
                    , FMessageBox::Ok, 0, 0, this );
   info.show();
 }

examples/treeview.cpp

@@ -168,25 +168,25 @@ Treeview::Treeview (FWidget* parent)
 
   static TreeItem europe[] =
   {
-    { "Austria",	"8,794,267",	"104.0", 0 },
+    { "Austria", "8,794,267", "104.0", 0 },
-    { "Belarus",	"9,498,700",	"45.8", 0 },
+    { "Belarus", "9,498,700", "45.8", 0 },
-    { "Bulgaria",	"7,101,859",	"64.9", 0 },
+    { "Bulgaria", "7,101,859", "64.9", 0 },
-    { "Czech Republic",	"10,610,947",	"134.0", 0 },
+    { "Czech Republic", "10,610,947", "134.0", 0 },
-    { "Finland",	"5,506,312",	"16.0", 0 },
+    { "Finland", "5,506,312", "16.0", 0 },
-    { "France",	"66,991,000",	"103.0", 0 },
+    { "France", "66,991,000", "103.0", 0 },
-    { "Germany",	"82,175,700",	"227.0", 0 },
+    { "Germany", "82,175,700", "227.0", 0 },
-    { "Greece",	"11,183,716",	"82.0", 0 },
+    { "Greece", "11,183,716", "82.0", 0 },
-    { "Hungary",	"9,797,561",	"105.3", 0 },
+    { "Hungary", "9,797,561", "105.3", 0 },
-    { "Iceland",	"332,529",	"3.2", 0 },
+    { "Iceland", "332,529", "3.2", 0 },
-    { "Italy",	"60,589,445",	"201.3", 0 },
+    { "Italy", "60,589,445", "201.3", 0 },
-    { "Norway",	"5,267,146",	"15.8", 0 },
+    { "Norway", "5,267,146", "15.8", 0 },
-    { "Poland",	"38,634,007",	"123.0", 0 },
+    { "Poland", "38,634,007", "123.0", 0 },
-    { "Portugal",	"10,309,573",	"115.0", 0 },
+    { "Portugal", "10,309,573", "115.0", 0 },
-    { "Romania",	"19,638,000",	"84.4", 0 },
+    { "Romania", "19,638,000", "84.4", 0 },
-    { "Serbia",	"7,058,322",	"91.1", 0 },
+    { "Serbia", "7,058,322", "91.1", 0 },
-    { "Spain", "46,468,102",	"92.0", 0 },
+    { "Spain", "46,468,102", "92.0", 0 },
-    { "Sweden",	"10,065,389",	"22.0", 0 },
+    { "Sweden", "10,065,389", "22.0", 0 },
-    { "United Kingdom",	"65,648,000", "270.7", 0 },
+    { "United Kingdom", "65,648,000", "270.7", 0 },
     { 0, 0, 0, 0 }
   };
 
@@ -266,12 +266,6 @@ Treeview::Treeview (FWidget* parent)
     continent_list++;
   }
 
-  FObjectIterator iter = listView->beginOfList();
-  FObjectIterator iter_africa = iter++;
-  FListViewItem* item_africa = static_cast<FListViewItem*>(*iter_africa);
-  item_africa->expand();
-
-
   // Quit button
   Quit = new FButton (this);
   Quit->setGeometry(24, 16, 10, 1);

src/fobject.cpp

@@ -35,13 +35,15 @@ const FString*      fc::empty_string    = 0;
 FObject::FObject (FObject* parent)
   : widget_object(false)
   , parent_obj(parent)
-  , children_list()              // no children yet
+  , children_list()            // no children yet
   , has_parent(false)
 {
-  if ( parent_obj )              // add object to parent
+  if ( parent )                // add object to parent
-    parent_obj->addChild(this);
+  {
-
+    parent->addChild(this);
-  if ( parent == 0 )
+    has_parent = true;
+  }
+  else
   {
     timer_modify_lock = false;
 
@@ -71,17 +73,11 @@ FObject::FObject (FObject* parent)
       }
     }
   }
-  else
-    has_parent = true;
 }
 
 //----------------------------------------------------------------------
 FObject::~FObject()  // destructor
 {
-  if ( parent_obj )
-    parent_obj->delChild(this);
-
-  parent_obj = 0;
   delOwnTimer();  // delete all timers of this object
 
   if ( ! has_parent && timer_list )
@@ -110,6 +106,11 @@ FObject::~FObject()  // destructor
       ++iter;
     }
   }
+
+  if ( parent_obj )
+    parent_obj->delChild(this);
+
+  parent_obj = 0;
 }
 
 // public methods of FObject

src/fstring.cpp

@@ -2482,13 +2482,13 @@ inline void FString::_assign (const wchar_t* s)
 //----------------------------------------------------------------------
 inline void FString::_insert (uInt pos, uInt len, const wchar_t* s)
 {
+  if ( len == 0 )  // String s is a null or a empty string
+    return;
+
   if ( ! string )
   {
     // string is null
 
-    if ( len == 0 )  // String s is also a null string
-      return;
-
     length = len;
     bufsize = FWDBUFFER + length + 1;
 
@@ -2512,7 +2512,7 @@ inline void FString::_insert (uInt pos, uInt len, const wchar_t* s)
     if ( (length + len + 1) <= bufsize )
     {
       // output string <= bufsize
-      for (x = length; x + 1 > pos; x--)  // shifting right side  + '\0'
+      for (x = length; x + 1 > pos; x--)  // shifting right side + '\0'
         string[x + len] = string[x];
 
       for (x = 0; x < len; x++)           // insert string