buffered-sql detail

Gabriel Blanchard gabe at teksavvy.ca
Tue Aug 11 21:42:22 CEST 2009

On 11-Aug-09, at 3:46 AM, Alan DeKok wrote:

> Gabriel Blanchard wrote:
> > mmm never mind, I just looked up the old code for  
> rlm_sql_freetds.c and
> > does appear to be using an old API. So I'm assuming that if I code  
> it
> > against the new API and submit a patch it would be welcome?
>   Yes.

Well I just spent the entire day coding this module and I wasted about  
90% of that time on FreeTDS getting stuck for ever it the query times  
out (I purposely made them timeout to test it). After looking at the  
source code of FreeTDS it turns out that the dbsettime() function that  
is supposed to set a timeout value for the dbsqlexec() function  
doesn't even work!

So I figured out a work around, by using the dbsetinterrupt function  
to set a call back. It calls whatever pointer of a function defined by  
us about once a second. This function can then be used to cancel the  
query after a certain amount of time.

So it turns out that the problem isn't really with unixODBC but rather  
FreeTDS itself...in a sense anyway. I also found that a lot of other  
projects that use FreeTDS have this exact same problem.

All and all, the module I just coded works and is able to INSERT or  
UPDATE the database. I haven't implemented SELECTs yet.


More information about the Freeradius-Devel mailing list