FreeTDS Development Group

[Chris Eleveld <ihermit2 AT yahoo.com>]

   I am using a stock Sybase interfaces file as
opposed to a freetds.conf mostly out of laziness.
I'm assuming there are no PowerPC NT users left out
there so we may need to determine a way to separate a
big endian client talking to a little endian server
and big endian client talking to a little endian
client.  Maybe there is something in the magic bytes
left in the TDS protocol specification.

--- Michael Horowitz
<michael.horowitz AT storagenetworks.com> wrote:
> I was using TDS version 4.2 in my tests.
> 
> --Mike
> 
> > I just ran a test.  Maybe we need a check against
> the
> > protocol level.  I'm using TDS version 4.6
> protocol
> > from AIX with FreeTDS to Solaris with Sybase.
> > 
> > Does anyone have an eclectic set of servers and a
> big
> > endian client?
> > 
> > Maybe we need the change to depend on wether you
> > enable the mssql stuff or another config flag? 
> for
> > TDSVER set to 4.2, 4.6, and 5.0 however with the
> > servers I have to chat to I don't get any messages
> > unless I use the if I have.  But, both machines in
> any
> > of my configurations are big endian. 
> > 
> > --- Michael Horowitz
> > <michael.horowitz AT storagenetworks.com> wrote:
> > > Hey Chris,
> > > 
> > > There was a thread about the big endian issue
> 2-3
> > > weeks ago(I am
> > > connecting from a Solaris box).  I came across
> the
> > > same problem.  I
> > > initially just erased the second swap, but I was
> > > informed that would cause
> > > problems when "emulate little endian" wasn't on.
> 
> > > So, I conditioned the
> > > second swap on "if (!tds->emul_little_endian)". 
> I
> > > noticed you did "if
> > > (tds->emul_little_endian)" in your patch, are
> you
> > > sure you didn't mean the
> > > other way?  tds_get_int does the swap if
> > > emul_little_endian is true, so
> > > you only want to swap it if tds_get_int didn't
> swap
> > > it already, which is
> > > if emul_little_endian is false.
> > > 
> > > In my experience with MS SQL Server 7.0, I MUST
> use
> > > emul_little_endian,
> > > otherwise the datetime fields have their bytes
> > > backwards and the "swap
> > > broken dates" seems to do nothing for me.
> > > 
> > > I tested this fix on MS SQL Server 7.0 and 2000
> with
> > > mixed results.
> > > This is what I wrote in a previous email about
> it:
> > > "Actually, I tried SQL Server 2000 without
> > > "emulate-little-endian" and
> > > with
> > > that swap removed and the datetime fields are
> fine
> > > and so are the error
> > > messages.
> > > With SQL Server 7.0 with the same setup, the
> > > datetime fields are wrong,
> > > and the error messages are messed up.
> > > 
> > > I tried using the following instead of
> completely
> > > removing the swap:
> > > if (!tds->emul_little_endian) {
> > >        tds_swap_bytes(&rc, 4);
> > > }
> > > That fixed the error messages on SQL Server 7.0,
> but
> > > then they were
> > > screwed up on SQL Server 2000."
> > > 
> > > Anyway, it seems that you have had a similar
> problem
> > > with the big endian
> > > issue as me, so I wanted to chyme in with my
> > > experience with it.  While
> > > either of the fixes seems to work under specific
> > > configurations, I am not
> > > sure what the final fix should be to make it
> work
> > > under all platforms and
> > > with all types of SQL Servers both MS and
> Sybase.
> > > 
> > > Do you have any other info that might help with
> > > this?
> > > 
> > > Thanks,
> > > 
> > > Mike
> > > 
> > > 
> > > > below is a patch that includes what I did for
> the
> > > > strange serve on my network.  More importantly
> > > however
> > > > are the changes for big endian platforms
> towards
> > > the
> > > > end with messages.  The symptom I was seeing
> was
> > > that
> > > > errors and messages were not being handled. 
> > > trackign
> > > > through the code this appeared to be
> happenning
> > > > because of a double endian swap.  I have also
> had
> > > to
> > > > make some changes to the dblib call to the
> message
> > > > handler as it did not pass the final argument
> of
> > > the
> > > > line number.  I will send that patch as it is
> > > rather
> > > > simple if anyone needs it.
> > > > 
> > > > 
> > > > *** freetds-0.53-orig/src/tds/token.c   Sun
> Nov 25
> > > > 19:04:17 2001
> > > > --- freetds-0.53/src/tds/token.c        Fri
> Jan 18
> > > > 14:54:07 2002
> > > > ***************
> > > > *** 185,192 ****
> > > >                                 ack =
> > > > tds_get_byte(tds);
> > > >                                 major_ver =
> > > > tds_get_byte(tds);
> > > >                                 minor_ver =
> > > > tds_get_byte(tds);
> > > > !                               tds_get_n(tds,
> > > NULL,
> > > > len-4);
> > > > !                              
> tds_get_byte(tds);
> > > >   #ifdef WORDS_BIGENDIAN
> > > >   /*
> > > >                                 if
> (major_ver==7)
> > > {
> > > > --- 185,219 ----
> > > >                                 ack =
> > > > tds_get_byte(tds);
> > > >                                 major_ver =
> > > > tds_get_byte(tds);
> > > >                                 minor_ver =
> > > > tds_get_byte(tds);
> > > > !                               if ((major_ver
> ==
> > > 4)
> > > > && (minor_ver == 6)) {
> > > > !                                   int tlen;
> > > > !                                   char
> > > > servname[1024];
> > > > !
> > > > !                                  
> > > tds_get_byte(tds);
> > > > /* teeny version */
> > > > !                                  
> > > tds_get_byte(tds);
> > > > /* tiny version */
> > > > !                                   tlen =
> > > > tds_get_byte(tds); /* servname len */
> > > > !                                   if (tlen
> >=
> > > > sizeof(servname))
> > > > !                                       tlen =
> > > > sizeof(servname) - 1;
> > > > !                                  
> tds_get_n(tds,
> > > > servname, tlen);
> > > > !                                  
> servname[tlen]
> > > =
> > > > '\000';
> > > > !                                   if
> > > > (!strcmp(servname, "OpenServer")) {
> > > > !                                       if
> (ack ==
> > > 0)
> > > > succeed=TDS_SUCCEED;
> > > > !                                   }
> > > > !                                   /* eat the
> > > rest of
> 
=== message truncated ===


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