Wireshark mailing list archives
How to troubleshoot extcap applications?
From: Jirka Novak <j.novak () netsystem cz>
Date: Wed, 1 Dec 2021 14:18:05 +0100
Hi, I noticed issue below and I propose a solution for it. Can I ask for comments? Every extcap tool has --debug and --debug-file options, but when they are used, it do "nothing". File is created, but it is empty. Later I found that it must be used with --log-level=debug to really log messages. The issue is that when you increase --log-level, it logs to console (STDERR). So when extcap is started from Wireshark, it mixes log output with packet data and wireshark gets confused and I found no way how to make it operational. In other words you can't use debug of extcap from Wireshark. In code I found that the reason is that wsutils/wscode.c writes every message to STDERR. If application registers additional file, it is copied to it too, but output to STDERR is made in every case. Applications can replace default writer to STDERR, but no extcap do it. My proposal is to modify extcap/extcap-base.c: 1) When --debug is used, set log level to debug so you don't have to add --log-level 2) If --log-file used, register custom log writer with ws_log_init_with_writer() which will discard all messages so just write to file will be made. 3) Update log init in every extcap Change is quite simple, but involves all extcaps. I already tested it and it works. I'm just not sure every extcap. I'm ready to prepare patch. Best regards, Jirka ___________________________________________________________________________ Sent via: Wireshark-dev mailing list <wireshark-dev () wireshark org> Archives: https://www.wireshark.org/lists/wireshark-dev Unsubscribe: https://www.wireshark.org/mailman/options/wireshark-dev mailto:wireshark-dev-request () wireshark org?subject=unsubscribe
Current thread:
- How to troubleshoot extcap applications? Jirka Novak (Dec 01)
- Re: How to troubleshoot extcap applications? Dario Lombardo (Dec 01)
- Re: How to troubleshoot extcap applications? Roland Knall (Dec 01)
- Re: How to troubleshoot extcap applications? Jirka Novak (Dec 01)
- Re: How to troubleshoot extcap applications? Roland Knall (Dec 01)
- Re: How to troubleshoot extcap applications? João Valverde (Dec 01)
- Re: How to troubleshoot extcap applications? Dario Lombardo (Dec 01)