FreeTDS Development Group

[Brian Bruns <camber AT ais.org>]

I checked in a fix (hopefully it's a fix ;-)  I had had one brewing when I 
got your patch, but the final was a blend of the two.  Someone want to 
give it a try?

Cheers,

Brian

On Wed, 14 Aug 2002, Varley, David(CBorn at Alcoa) wrote:

> 
> Dave,
> 
> I agree with your proposed solution, in fact I'd suggest taking
> it a step further and replacing the entry in the TDSSOCKET structure
> with a void pointer for the use of the iconv functions. This enables
> us to hide all the iconv details within functions in iconv.c, and
> gets the conditional stuff right out of tds.h. The functions themselves
> then take the appropriate actions depending whether the system supports
> it. The only files needing modification would be tds.h, iconv.c and
> mem.c.
> 
> Brian, I'm happy to make those mods if you agree with this.
> 
> David
> 
> > -----Original Message-----
> > From: Coleman, Dave [mailto:DColeman AT US.TIAuto.com]
> > Sent: Tuesday, 13 August 2002 10:14 PM
> > To: TDS Development Group
> > Subject: [freetds] Re: Crash in tsql
> > 
> > 
> > It's a day late, but if you're still looking for suggestions 
> > to help with
> > the ICONV mis-match, I think this might work.  What does 
> > anyone else think?
> > 
> > Set up the ICONV stuff be a small structure pointer in TDSSOCKET.  
> > 
> > Something like:
> > 
> > struct tds_iconv_info
> > {
> >     int use_iconv;
> >     iconv_t cdto;
> >     iconv_t cdfrom;
> > }   TDSICONVINFO;
> > 
> > then TDSSOCKET would look something like this
> > 
> > ...
> >     TDSICONVINFO *tds_iconv;
> >     char *date_fmt;
> >     TDSCONTEXT *tds_ctx;
> > } TDSSOCKET;
> > 
> > modify tds_alloc_socket(...)
> > 
> > 371:                tds_socket->parent = (char*)NULL;
> >     +       tds_socket->tds_iconv = (char*)NULL;
> > 372:                tds_socket->env = tds_alloc_env(tds_socket);
> > 
> > add a few functions:
> > 
> > TDSICONVINFO* tds_alloc_iconv(TDSSOCKET *tds);
> > void tds_free_iconv(TDSSOCKET *tds);
> > and
> > TDSICONVINFO* tds_geticonv(TDSSOCKET *tds)
> >     {
> >     /*
> >     1) do some environment stuff to find if can use iconv on the
> > system...
> >             might be sloppy, but keeps ICONV out of TDSSOCKET.
> >             Someone with a better knowledge of 
> > configuration stuff than
> >             myself may know a good way to get this information out
> >             of the system at run time.
> >     */
> >     if( /* has iconv stuff */)
> >             {
> >             tds->tds_iconv = tds_alloc_iconv(tds);
> >             }
> >     /*
> >     do what ever else you need to do to set things up
> >     */
> >     return tds->tds_iconv;
> >     }
> > 
> > add a call to tds_free_iconv(...) from tds_free_socket(...) 
> > and you should
> > be done unless I've missed something dumb.
> > 
> > It doesn't solve the root problem of needing to determine if 
> > a system has
> > ICONV support at run-time, but it does allow the TDSSOCKET 
> > structure (and
> > the library) to be independent of ICONV.  It could simplify 
> > the functions
> > dealing with it as well.  The prototpe would not change at 
> > all, they would
> > still get a TDSSOCKET.  Compile the library with the 
> > tds_iconv[xxx](...)
> > functions if the headers exist on the system, and the 
> > functions can test for
> > if ( tds_socket->tds_iconv ) and as long as 
> > tds_alloc_socket(...) sets the
> > tds_iconv pointer to NULL, any tds_iconvblah(...) function 
> > can fail safely
> > if no support is present, or it has not been initialized.  This could
> > prevent people from trying to use the features if they had 
> > not been compiled
> > into the library without including config.h.  The library 
> > would compile but
> > the application would not if it tried to link in the ICONV 
> > functions on a
> > system with an ICONV-less OS or freeTDS distribution.  It's 
> > still a link
> > error and not completely clean, but that's a heck of a lot 
> > better than a
> > seg-fault.
> > 
> > Thoughts, comments?
> > 
> > Dave
> > 
> > > -----Original Message-----
> > > From:     Brian Bruns [SMTP:camber AT ais.org]
> > > Sent:     Monday, August 12, 2002 10:37 AM
> > > To:       TDS Development Group
> > > Subject:  [freetds] Re: Crash in tsql
> > > 
> > > Actually, this fix is bad, since we don't distribute 
> > config.h (nor should
> > > we) things won't build.  If we don't do it in the header 
> > file however, we
> > > are in trouble of having mismatched structure definitions.  
> > We didn't
> > > really notice it before because iconv_t cdto, cdfrom was 
> > the last entry.
> > > 
> > > We simply can't be checking HAVE_ICONV in tds.h (or any 
> > distributable
> > > header).  We could substitute from configure but that strikes me as
> > > sloppy.  Any other options?
> > > 
> > > Brian
> > > 
> > > > Ok, I was on the right track, sizeof(*tds) differed 
> > between the two, I 
> > > > just didn't have time to finish it off.  config.h should 
> > be included
> > > from
> > > > tds.h (tds.h.in) otherwise we'll have this problem again 
> > in the future.
> > > > 
> > > > Checking the fix in now.
> > > > 
> > > > Brian
> > > > 
> > > > On Sun, 11 Aug 2002 freddyz77 AT tin.it wrote:
> > > > 
> > > > > > This has been the topic of discussion for the past 
> > couple of days.
> > > For
> > > > > > some reason tds->tds_ctx is NULL after the call to 
> > tds_connect(),
> > > although
> > > > > > it is set within tds_connect().  I haven't had a 
> > chance to track it
> > > any
> > > > > > further.
> > > > > > 
> > > > > > Brian
> > > > > > 
> > > > > 
> > > > > Ok, after a bit debug (assembly level at the end) I 
> > found the problem.
> > > > > You do not include config.h in tsql, so tds_socket 
> > appear to tsql
> > > without
> > > > > iconv stuff.
> > > > > 
> > > > > Add "#include <config.h>" on top of tsql.c and it run correctly.
> > > > > Perhaps is best to include config.h from tds.h.in ...
> > > > > 
> > > > > freddy77
> > > > >
> > > 
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