vncviewer crashes when maximizing viewwindow

[Jurgis Pralgauskis]

I use Ubuntu 7.10 based Baltix distribution, the same on the other end
I just pressed Maximize (Alt+F10 or so) in viewer and it crashed

VNC Viewer Free Edition 4.1.1 for X - built Sep 10 2007 17:17:04
Copyright (C) 2002-2005 RealVNC Ltd.
See http://www.realvnc.com for information on VNC.

Fri Mar 14 13:48:13 2008
 CConn: connected to host ...

Fri Mar 14 13:48:14 2008
 CConnection: Server supports RFB protocol version 3.7
 CConnection: Using RFB protocol version 3.7

Fri Mar 14 13:48:17 2008
 TXImage: Using default colormap and visual, TrueColor, depth 24.
 CConn: Using pixel format depth 6 (8bpp) rgb222
 CConn: Using ZRLE encoding
vncviewer: TXScrollbar.cxx:47: void TXScrollbar::set(int, int, int, bool): Assertion `limit_ > 0 && len_ >= 0 && len_ <= limit_' failed.
Aborted

[Brian Amberg (ubuntu-brian-amberg)]

The same happens to me when using xmonad. As soon as i push it into tiled layout, it crashes.

VNC Viewer Free Edition 4.1.1 for X - built Apr 16 2008 13:23:14
Copyright (C) 2002-2005 RealVNC Ltd.
See http://www.realvnc.com for information on VNC.

Tue Sep 23 13:14:48 2008
 CConn: connected to host localhost port 1111
 CConnection: Server supports RFB protocol version 3.8
 CConnection: Using RFB protocol version 3.8

Tue Sep 23 13:14:52 2008
 TXImage: Using default colormap and visual, TrueColor, depth 24.
 CConn: Using pixel format depth 6 (8bpp) rgb222
 CConn: Using ZRLE encoding
vncviewer: TXScrollbar.cxx:47: void TXScrollbar::set(int, int, int, bool): Assertion `limit_ > 0 && len_
>= 0 && len_ <= limit_' failed.

[Brian Amberg (ubuntu-brian-amberg)]

This is the same as bug #281167

This can be fixed by replacing the assertion in TXScrollbar::set with

if (len_ > limit_) len_ = limit_;

such that TXScrollbar::set looks like this

void TXScrollbar::set(int limit_, int start_, int len_, bool vert)
{
  // This assertion fails under certain window managers.
  // assert(limit_ > 0 && len_ >= 0 && len_ <= limit_);

  if (len_ > limit_) len_ = limit_;
  if (start_ < 0) start_ = 0;
  if (start_ > limit_ - len_) start_ = limit_ - len_;

  if (limit[vert] != limit_ || start[vert] != start_ || len[vert] != len_) {
    limit[vert] = limit_;
    start[vert] = start_;
    len[vert] = len_;
    paint();
  }
}

I hope this patch is helpful.

best regards,

Brian Amberg