X-Git-Url: http://www.lcore.org/git/lcore.git/blobdiff_plain/4782a5c5afee47721cc617daa40dd29828342c2b..a1858883733a454b6ffb73aa263ef5badc2a1d07:/blinklist.pas

diff --git a/blinklist.pas b/blinklist.pas
index 2079b75..5ab153a 100755
--- a/blinklist.pas
+++ b/blinklist.pas
@@ -1,21 +1,9 @@
-(*
- *  beware IRC services, blinklist.pas
- *  Copyright (C) 2002 Bas Steendijk
- *
- *  This program is free software; you can redistribute it and/or modify
- *  it under the terms of the GNU General Public License as published by
- *  the Free Software Foundation; either version 2 of the License, or
- *  (at your option) any later version.
- *
- *  This program is distributed in the hope that it will be useful,
- *  but WITHOUT ANY WARRANTY; without even the implied warranty of
- *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- *  GNU General Public License for more details.
- *
- *  You should have received a copy of the GNU General Public License
- *  along with this program; if not, write to the Free Software
- *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
- *)
+
+{ Copyright (C) 2005 Bas Steendijk
+  For conditions of distribution and use, see copyright notice in zlib_license.txt
+    which is included in the package
+      ----------------------------------------------------------------------------- }
+
 unit blinklist;
 {$ifdef fpc}
   {$mode delphi}
@@ -67,10 +55,13 @@ var
 
 implementation
 
+uses sysutils;
+
 procedure linklistadd(var baseptr:tlinklist;newptr:tlinklist);
 var
   p:tlinklist;
 begin
+  if (newptr=baseptr) or assigned(newptr.prev) then raise exception.create('linklist double insertion detected');
   p := baseptr;
   baseptr := newptr;
   baseptr.prev := nil;
@@ -83,12 +74,15 @@ begin
   if item = baseptr then baseptr := item.next;
   if item.prev <> nil then item.prev.next := item.next;
   if item.next <> nil then item.next.prev := item.prev;
+  item.prev := nil;
+  item.next := nil;
 end;
 
 procedure linklist2add(var baseptr,newptr:tlinklist2);
 var
   p:tlinklist2;
 begin
+  if (newptr=baseptr) or assigned(newptr.prev2) then raise exception.create('linklist2 double insertion detected');
   p := baseptr;
   baseptr := newptr;
   baseptr.prev2 := nil;
@@ -101,6 +95,8 @@ begin
   if item = baseptr then baseptr := item.next2;
   if item.prev2 <> nil then item.prev2.next2 := item.next2;
   if item.next2 <> nil then item.next2.prev2 := item.prev2;
+  item.prev2 := nil;
+  item.next2 := nil;
 end;
 
 constructor tlinklist.create;