Back Midas Rome Roody Rootana
  Midas DAQ System  Not logged in ELOG logo
Entry  01 Mar 2018, Andreas Suter, Bug Report, mhttpd / odb set strings -> truncates odb entry 
    Reply  02 Mar 2018, Stefan Ritt, Bug Report, mhttpd / odb set strings -> truncates odb entry 
       Reply  05 Mar 2018, Andreas Suter, Bug Report, mhttpd / odb set strings -> truncates odb entry 
    Reply  18 Apr 2018, Thomas Lindner, Bug Fix, mhttpd / odb set strings -> truncates odb entry 
Message ID: 1345     Entry time: 05 Mar 2018     In reply to: 1344
Author: Andreas Suter 
Topic: Bug Report 
Subject: mhttpd / odb set strings -> truncates odb entry 
> > There is a bug in the string handling when changing ODB string entries via the
> > mhttpd (git sha 07dfb83). It truncates the string length in the ODB.
> > 
> > For instance I create a string with length 32 and set it with odbedit to 'a'.
> > Then the string length stays 32, as expected. If the same is done through the
> > web-interface, the string length will be truncated to 2.
> > 
> > This can lead to problems if some frontend has a hotlink to a structure
> > containing this string since it will complain about structure size mismatch. 
> 
> I know about this problem since last summer. I mentioned it to KO, since it's deep down in his 
> JSONRPC code. We had a long discussion, where he kind of insisted that this is not a bug but a 
> feature. The ODB should store strings with variable lengths, and thus adapt it according to the 
> current string length. This makes some sense, since in the future we plan to put C++ string 
> support for the ODB, where strings have dynamically varying lengths. But this will take a while, so 
> I asked KO to change the truncation of the strings though the web interface, because this breaks 
> many experiments. He did not react so far. Several people complained. Maybe your request will 
> help now.
> 
> Stefan

Well I appreciate the direction towards more C++ string handling, yet it must not break the hotlink
functionality which is very important at many places.
ELOG V3.1.4-2e1708b5