Keepass2 puts incorrect atom in clipboard targets list

[trespasserw]

On copying a password or entry into a clipboard Keepass2 puts an atom with id of zero into a list of formats. This makes it impossible to paste from Keepass2 into any Java program.

Following is a simple Java program which attempts to print clipboard content:
=== ClipRead.java ===
import java.awt.*;
import java.awt.datatransfer.*;

public class ClipRead {
  public static void main(String... args) throws Exception {
    Toolkit toolkit = Toolkit.getDefaultToolkit();
    Clipboard clipboard = toolkit.getSystemClipboard();
    Object data = clipboard.getData(DataFlavor.stringFlavor);
    System.out.println("[" + data + "]");
  }
}
=== ClipRead.java ===

Calling it after copying from Keepass2 results in a following exception:
$ java ClipRead
Atom was 0
Exception in thread "main" java.lang.NullPointerException: Failed to retrieve atom name.
 at sun.awt.X11.XlibWrapper.XGetAtomName(Native Method)
 at sun.awt.X11.XAtom.getName(XAtom.java:186)
 at sun.awt.X11.XDataTransferer.getTargetNameForAtom(XDataTransferer.java:164)
 at sun.awt.X11.XDataTransferer.getNativeForFormat(XDataTransferer.java:153)
 at sun.awt.datatransfer.DataTransferer.getFlavorsForFormats(DataTransferer.java:735)
 at sun.awt.datatransfer.SunClipboard.getData(SunClipboard.java:218)
 at ClipRead.main(ClipRead.java:8)

Expected result:
$ java ClipRead
[my password]

[Julian Taylor (jtaylor)]

do you have xsel installed? the builtin clipboard of mono which is used without xsel installed is know to have issues.

[trespasserw (trespasserw)]

No, I don't. Will try it next week, thanks.

[trespasserw (trespasserw)]

BTW does Keepass2 use gtk-sharp? Gtk.Clipboard seemed to work fine (at least in my tests).

[Julian Taylor (jtaylor)]

no keepass uses monos reimplementation of winforms which is the source of pretty much all bugs as it is terrible and unmaintained.
keepassx is a frontend to keepass databases that has a more native gui. I think its based on Qt. But i'm unfamiliar with how far its version 2 database support is.

[trespasserw (trespasserw)]

Well, it turned out to be xsel's problem - it corrupts the clipboard the same way when called manually.

[trespasserw (trespasserw)]

Proposed patch: https://github.com/trespasserw/xsel/commit/05f6172dc030bc81cda795e7f5e8cb351bc01ecc

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Colan Schwartz (colan)]

@trespasserw: The above URL returns a 404. Has it moved, been deleted, or is it no longer a public project?

[Colan Schwartz (colan)]

Workaround: Use KeePassX in these situations as both applications can share the same database.

[trespasserw (trespasserw)]

@colan the PR was accepted so I have dropped my fork. The commit is here: https://github.com/kfish/xsel/commit/05f6172dc030bc81cda795e7f5e8cb351bc01ecc

[Colan Schwartz (colan)]

Thanks, but I've recently switched to https://keepassxc.org/ so I no longer need keepass2. It's better, and solves many problems including this one. I'd recommend it for everyone.