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ID Date Author Topic Subjectdown
  130   12 Oct 2003 Konstantin Olchanski Array overruns in mhttpd.c::submit_elog()
> While adding new functionality to submit_elog() (add the message text to the
> outgoing email), I noticed that the email text is being stored into an array
> of size 256, mail_text[256], without any checks for array overrun. This
> cannot be good. How should this be corrected?
> K.O.

Similar problem exists in midas.c::el_submit(). The array "message[10000]" is
easy to overrun by submitting a long elog message.

K.O.
  131   13 Oct 2003 Stefan Ritt Array overruns in mhttpd.c::submit_elog()
> > While adding new functionality to submit_elog() (add the message text to 
the
> > outgoing email), I noticed that the email text is being stored into an 
array
> > of size 256, mail_text[256], without any checks for array overrun. This
> > cannot be good. How should this be corrected?
> > K.O.
> 
> Similar problem exists in midas.c::el_submit(). The array "message[10000]" 
is
> easy to overrun by submitting a long elog message.
> 
> K.O.

The whole elog functionality in mhttpd will be replaced (sometime) by the 
standalone ELOG package, linked against mhttpd. The ELOG functionality is 
much richer and does not conatin all the mentioned problems which have been 
fixed there some time ago. For the time being it might however be worth to 
fix the mentioned problems, but without spending too much time on it.
  132   13 Oct 2003 Konstantin Olchanski Array overruns in mhttpd.c::submit_elog()
> > > While adding new functionality to submit_elog() ....
> 
> The whole elog functionality in mhttpd will be replaced (sometime) ...

I humbly submit that this has been the standard reply for the last 2 years since I was aware of 
the "last N days does not always work" problem (just saw it again yesterday).

K.O.
  725   23 Sep 2010 Stefan RittInfoAnother example of a JavaScript midas page
Please find attached another example of a JavaScript (JS) page using the 
ODBGet/Set functions. 

In contrast to the previous posting, the page is not constructed via the 
document.writeln() function, but written directly in HTML and modified through the 
"innerHTML = ..." functionality. 

It is a control page for our beamline, which gets updated in the background. In 
addition, the user can set the beamline to three predefined settings which are 
stored in an array at the top of the page. As an little extra there is a progress 
bar, which is updated locally via JS since changing the beamline takes a while. 
The progress bar is implemented as a table with variable width, and dynamically 
updated by the JS program. The second attachment is a screen dump from such a 
switching process. Since only values in the ODB are changed, you can try it 
yourself without actually modifying a PSI beam line ;-)
  563   04 Mar 2009 Dawei LiuForumAnalyzer gets killed cm_watchdog
Hello Midas experts:

We have setup a DAQ using MIDAS to readout two ADCs in the crate.
We are running into problem of analyzer getting killed between 
runs.  Sometimes it would crash after a few runs and sometimes it 
would go on for many many runs before analyzer gets killed.  It always 
occurred between runs not when we are taking data.  Any suggestions 
on what we could try?  The error message from the midas.log file is 
appended below.

Thanks,

Dawei

Wed Mar  4 11:53:11 2009 [Analyzer,ERROR] [midas.c:1739:,ERROR]
cm_disconnect_experiment not called at end of program
Wed Mar  4 11:53:22 2009 [mhttpd,INFO] Client 'Analyzer' on buffer 'SYSMSG'
removed by cm_watchdog (idle 10.7s,TO 10s)
Wed Mar  4 11:53:22 2009 [mhttpd,INFO] Client 'Analyzer' (PID 1) on buffer 'ODB'
removed by cm_watchdog (idle 10.7s,TO 10s)
Wed Mar  4 11:53:22 2009 [AL Experiment Frontend,INFO] Client 'Analyzer' on
buffer 'SYSTEM' removed by cm_watchdog (idle 10.9s,TO 10s)
Wed Mar  4 11:53:29 2009 [AL Experiment Frontend,TALK] starting new run
Wed Mar  4 11:53:29 2009 [AL Experiment Frontend,ERROR]
[midas.c:8264:rpc_client_check,ERROR] Connection broken to "Analyzer" on host
tsunami
  564   24 Mar 2009 Stefan RittForumAnalyzer gets killed cm_watchdog
Hi,

your log script sound to me like the analyzer either got into an infinite loop or 
did a segment violation and just died. I would recommend to run the analyzer from 
inside the debugger. When you then get the segment violation, you can inspect the 
stack trace and see where the bad things happen. Since the analyzer works nicely in 
other experiment, I expect that your problem is related to the user code. Maybe it 
happens at the end of the run, but there is a timeout before the crashed process 
gets cleaned from the ODB, that's why you might think that it happens "between" 
runs.

Best regards,

  Stefan

> 
> Hello Midas experts:
> 
> We have setup a DAQ using MIDAS to readout two ADCs in the crate.
> We are running into problem of analyzer getting killed between 
> runs.  Sometimes it would crash after a few runs and sometimes it 
> would go on for many many runs before analyzer gets killed.  It always 
> occurred between runs not when we are taking data.  Any suggestions 
> on what we could try?  The error message from the midas.log file is 
> appended below.
> 
> Thanks,
> 
> Dawei
> 
> Wed Mar  4 11:53:11 2009 [Analyzer,ERROR] [midas.c:1739:,ERROR]
> cm_disconnect_experiment not called at end of program
> Wed Mar  4 11:53:22 2009 [mhttpd,INFO] Client 'Analyzer' on buffer 'SYSMSG'
> removed by cm_watchdog (idle 10.7s,TO 10s)
> Wed Mar  4 11:53:22 2009 [mhttpd,INFO] Client 'Analyzer' (PID 1) on buffer 'ODB'
> removed by cm_watchdog (idle 10.7s,TO 10s)
> Wed Mar  4 11:53:22 2009 [AL Experiment Frontend,INFO] Client 'Analyzer' on
> buffer 'SYSTEM' removed by cm_watchdog (idle 10.9s,TO 10s)
> Wed Mar  4 11:53:29 2009 [AL Experiment Frontend,TALK] starting new run
> Wed Mar  4 11:53:29 2009 [AL Experiment Frontend,ERROR]
> [midas.c:8264:rpc_client_check,ERROR] Connection broken to "Analyzer" on host
> tsunami
  436   18 Feb 2008 Jimmy NgaiBug ReportAnalyzer cannot run as Daemon
Hi All,

I'm testing MIDAS SVN rev-4113 on Scientific Linux 5.1 (i386) and the Analyzer 
can't start as Daemon. What I mean "can't" is that it stops running 
immediately without leaving any error messages. However, it can run offline or 
without becoming a Daemon. I have tested with ROOT 5.14e/5.16/5.18 and 
the "Experiment" example coming with MIDAS and this problem always happens. 
Any ideas?

Best Regards,
Jimmy
  2438   14 Oct 2022 Lars MartinSuggestionAllow onchange to refer to arbitrary js function
Maybe this is already possible, I have a hard time understanding the mhttpd source code.

I would like to use a function defined in the <script> block of my custom page as an onchange callback.

Specific example:
I have an modbthermo that I would like to change to three different colours for "too cold", "just right", and "too hot" (measuring porridge, presumably). The examples only show the explicit (condition)?(val1):(val2) syntax, which doesn't allow more than two values, so I had hoped to replace

onchange="this.dataset.color=this.value > 40?'red':'blue';"

with something like

onchange="this.dataset.color=check_Temp(this.value);"

or

onchange="check_Temp(this.value, this.dataset.color);"

if that's easier somehow. The function itself would then return the colour string, or set the color argument to that string (I'm not sure if JS passes references or just values.)

Is this a possibility?
  2439   14 Oct 2022 Ben SmithInfoAllow onchange to refer to arbitrary js function
> I would like to use a function defined in the <script> block of my custom page as an onchange callback.
>
> Is this a possibility?

Yes, this is already possible. An example was shown in the "modb" section of the custom page documentation, but not in the "Changing properties of controls dynamically" section. I've updated the wiki with an example.

https://daq00.triumf.ca/MidasWiki/index.php/Custom_Page#Changing_properties_of_controls_dynamically
  2440   22 Oct 2022 Lars MartinInfoAllow onchange to refer to arbitrary js function
I figured I wasn't the first to have this idea.
Works great, thanks!
  2442   22 Oct 2022 Lars MartinInfoAllow onchange to refer to arbitrary js function
Actually, now that I look again, there is a mistake in the instructions:
you say

onchange="this.dataset.color=check_therm(this)"

but check_therm doesn't return anything and instead changes the color itself. So you either want the function to return the string and use the above assignment, or use the function you provide and use

onchange="check_therm(this)"
  1191   23 Aug 2016 Andreas SuterForumAlarm/Warning
Midas has a nice alarm system. I am wondering whether it is easily possible to
get the Alarm/Warning banner also on top of custom pages?!
  1192   23 Aug 2016 Stefan RittForumAlarm/Warning
> Midas has a nice alarm system. I am wondering whether it is easily possible to
> get the Alarm/Warning banner also on top of custom pages?!

K.O. made nice JavaScript routines to access the alarm status. The new alarm page is completely 
made dynamically from JavaScript code (mhttpd does not supply any HTML code any more, only 
functions to obtain ODB values etc). Part of this new dynamic page must be some code to display 
the alarm status. You just need to copy this to your custom page. K.O. can tell you details.

Stefan
  1206   30 Sep 2016 Konstantin OlchanskiForumAlarm/Warning
> > Midas has a nice alarm system. I am wondering whether it is easily possible to
> > get the Alarm/Warning banner also on top of custom pages?!
> 
> K.O. made nice JavaScript routines to access the alarm status. The new alarm page is completely 
> made dynamically from JavaScript code (mhttpd does not supply any HTML code any more, only 
> functions to obtain ODB values etc). Part of this new dynamic page must be some code to display 
> the alarm status. You just need to copy this to your custom page. K.O. can tell you details.
> 

Yes, please look at resources/alarm.html and the "get_alarms" JSON-RPC method. The "get_alarms" example in 
resources/example.html probably already does exactly what you need. Also note the presence of "al_reset_alarm" and 
"al_trigger_alarm" JSON_RPC methods.

K.O.
  2411   19 Jun 2022 Francesco RengaForumAlarm on variable not updating
Dear all,
I've an ODB equipment that sometimes loses the connection with the hardware, so that the variables are not updated anymore. The connection can be restored by restarting the frontend. It would be useful to have an alarm based on the time from the last update of some variable (i.e. the alarm is triggered if the variable is not updated for more than X seconds). Is there a method to implement such an alarm in MIDAS?

Thank you very much,
Francesco
  2413   20 Jun 2022 Stefan RittForumAlarm on variable not updating
There are two functions to do that, one check the last write access, the other the last write access if the run is running. The alarm condition looks like:

access(/Equipment/.../Variables/Input[10]) > 60

which will cause an alarm if the Input[10] is not written for more than 60 seconds. The other function which checks the run status as well is like:

access_running(...odb key...) > 60

You can actually see an example on the MEG alarm page.

Rather than having an alarm for that I would however recommend that you program you frontend such that it realizes if it looses connections, then tries automatically to reconnect or trigger an alarm itself (so-called "internal" alarm). This is also how the MSCB system is working and is much more robust.

Stefan
  2   11 Aug 2003 Konstantin Olchanski Alarm on no ping?
I want midas alarms to go off when I cannot ping arbitrary remote hosts. Is
there is easy/preferred way to do this? K.O.
  4   18 Dec 2003 Stefan Ritt Alarm on no ping?
> I want midas alarms to go off when I cannot ping arbitrary remote hosts. Is
> there is easy/preferred way to do this? K.O.

There are "internal alarms" with type AT_EVALUATED. Just find a program 
where you can put some code which gets periodically executed (like the idle 
loop in the frontend), and so something like:

DWORD last = 0;

  if (ss_time() > last+60)
    {
    last = ss_time();

    /* do a ping via socket(), bind() and connect() */
    ...

    if (status != CM_SUCCESS)
      al_trigger_alarm("XYZ Ping", str, "Warning", 
                       "Host is dead", AT_INTERNAL);
    }

Pierre does the same thing in lazylogger.c, just have a look. I don't know 
how to do a ping correctly in C, I guess you have to send an UDP packet 
somewhere, but I never did it. If you find it out, please post it.


 
  412   17 Oct 2007 Randolf PohlForumAdding MIDAS .root-files
Dear MIDAS users,

I want to add several .root-files produced by the MIDAS analyzer, in a fast 
and convenient way. ROOT's hadd fails because it does not know how to treat 
TFolders. I guess this problem is not unique to me, so I hope that somebody of 
you might already have found a solution.

Why don't I just run "analyzer -r 1 10000"?
We have taken lots of runs under (rapidly) varying conditions, so it would be 
lots of "-r". And the analysis is quite involved, so rerunning all data takes 
about one hour on a fast PC making this quite painful.
Therefore, I would like to rerun all data only once, and then add the result 
files depending on different criteria.

Of course, I tried to write a script that does the adding. But somehow it is 
incredibly slow. And I am not the Master Of C++, too.

Is there any deeper reason for MIDAS using TFolders, not TDirectorys? ROOT's 
hadd can treat TDirectory. Can I simply patch "my" MIDAS? Is there general 
interest in a change like this? (Does anyone have experience with the speed of 
hadd?)

Looking forward to comments from the Forum.

Cheers,

Randolf
  415   17 Oct 2007 John M O'DonnellForumAdding MIDAS .root-files
The following program handles regular directories in a file, or folders (ugh).
Most histograms are added bin by bin.

For scaler events it is convenient to see the counts as a function of time (ala
sclaer history plots in mhttpd).  If the histogram looks like a scaler plot versus
time, then new bins are added on to the end (or into the middle!) of the histogram.

All different versions of cuts are kept.

TTrees are not explicitly supported, so probably don't do the right thing...

John.

> Dear MIDAS users,
> 
> I want to add several .root-files produced by the MIDAS analyzer, in a fast 
> and convenient way. ROOT's hadd fails because it does not know how to treat 
> TFolders. I guess this problem is not unique to me, so I hope that somebody of 
> you might already have found a solution.
> 
> Why don't I just run "analyzer -r 1 10000"?
> We have taken lots of runs under (rapidly) varying conditions, so it would be 
> lots of "-r". And the analysis is quite involved, so rerunning all data takes 
> about one hour on a fast PC making this quite painful.
> Therefore, I would like to rerun all data only once, and then add the result 
> files depending on different criteria.
> 
> Of course, I tried to write a script that does the adding. But somehow it is 
> incredibly slow. And I am not the Master Of C++, too.
> 
> Is there any deeper reason for MIDAS using TFolders, not TDirectorys? ROOT's 
> hadd can treat TDirectory. Can I simply patch "my" MIDAS? Is there general 
> interest in a change like this? (Does anyone have experience with the speed of 
> hadd?)
> 
> Looking forward to comments from the Forum.
> 
> Cheers,
> 
> Randolf
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