User interface hangs on incoming calls when LDAP server not reachable

[cweiske]

Describe the bug I have two LDAP servers configured, and one is only available when I'm connected to my office's VPN.

When the VPN is not connected and I receive an incoming call, the ring tone starts and the incoming call window appears, but I cannot do anything - the UI does not react. Even when the call is terminated externally, the ringtone still plays and the UI is still unresponsive.

I have to kill Linphone manually.

To Reproduce Steps to reproduce the behavior:

1. Add unreachable LDAP server (E.g. Domainname that cannot be resolved like "ldap://nas-001.mogic.company")
2. Get incoming call
3. Ringtone plays, Incoming call popup window appears
4. UI is unresponsive

Expected behavior The UI should not be blocked when an LDAP server cannot be reached/resolved.

Desktop (please complete the following information):

• OS: Ubuntu 20.04
• Version: Desktop 4.3.0-2-gb6751c9d
• Version of the SDK: Qt5.12.12, Core 5.0.39

SDK logs linphone-ldap-novpn.log

[cweiske]

Also happens when searching for contacts.