Re: {bb} problem monitoring kpop after upgrade, is buggy bbnet

[Robert-Andre Croteau <sirac@videotron.ca>]

Henrik Olsen wrote:
> 
> On Sat, 25 Sep 1999, Tracy J. Di Marco White wrote:
> > Henrik Olsen wrote:
> > }Not knowing kpop, I can't tell exactly why the delay is so long, but for
> > }other services it's often a failing reverse dns lookup or a failing
> > }auth/ident request, either of which might take a timeout before the
> > }service responds.
> Actually, my comments on the different timeouts between 1.09b and 1.2b
> where wrong, I was apparently looking at the 1.08a source instead of
> 1.09b:(

Well, the 1.09b and 1.2b versions I have are fairly different :(

> 
> There has been changes to the timeout handling but they both use the 3, 5,
> 12 approach, the difference between the versions is that 1.2b has a bug
> in handling timeouts when not receiving any data. :)
> 
> Sean/Rob, it looks like Tracy found a bug in bbnet, this patch will fix
> the problem:

I'm not sure but I'm open to all comments...

I've look at the previous messages to this thread and something caught
my eye:

I'm not sure if that's it:
# time /local2/bb-1.09b/bin/bbnet mailhub:1109
0.013u 0.016s 0:03.14 0.6% 0+1k 0+0io 0pf+0w
              ^^^^^^^
# time /local2/bb-1.2b/bin/bbnet mailhub:1109
bbnet: TIMEOUT mailhub PORT 1109...
0.003u 0.018s 0:20.04 0.0% 0+2k 0+0io 0pf+0w
              ^^^^^^^

Is this elapsed ?

If so, then it makes some sense,

1.09b would only go thru a 3seconds delay and quit while the 1.2b
would go thru the 3, 5 and 12 seconds delay for 20 seconds.

Now why would the 1.09b take only one 3 second delay ?  hummmm, let's
see:

in bbnet.c on 1.09b, the variable cnt is defined in timeout() as

static int cnt;

Maybe it wasn't initialized with 0 upon execution of the code.  So if
cnt >
2 at program startup (compiler SHOULD have initialized to 0 but there
might also be a bug in the compiler ...) then in the 1.09b version the
timeout() function would only be called once:

1.09b bbnet.c

timeout()
{
        static int cnt;
        ^^^^^^^^^^^^^^^  cnt should be 0 at startup

        cnt++;
        ^^^^^^  if cnt is initialized with > 2
        if (cnt == 1) timer = 5;
        else if(cnt == 2) timer = 12;
        else {
        ^^^^^^^^^^^ then it would jump to this else immediately and
        ^^^^^^^^^^^  report an elapsed time of 3 seconds...  cause 
        ^^^^^^^^^^^  timer 5 & 12 were skipped
                fprintf(stderr, "bbnet: TIMEOUT %s PORT %d...\n",
machine, port);
                exit(3);
        }
        longjmp(env,1);
}

> 245c245
> <       if (setjmp(env) != 0) {
> ---
> >       if (setjmp(env) != 0) { /* RETURN OK BUT INCLUDE MESSAGE */
> 247,248c247,248
> <                 debug("SETTING TIMER TO %d\n", timer);
> <               if (timer == 99) return(99);
> ---
> >               printf("*** bbnet: Stop waiting for server data\n");
> >               return(0);              /* PRETEND IT'S OK */

That's my take on it.

I think the bug was in 1.09b returning too quickly and that
version 1.2b behaves correctly but I could be wrong ;)

Tracy,  in the 1.09b code can you change

static int cnt;

	to

static int cnt = 0;

recompile and try the bbnet test again, let us know the result
You could even have a printf("\ncnt = %d\n",cnt); as the
first statement in the timeout function just to make sure
what the value of cnt is... maybe do it before the = 0 change
to confirm the bug on 1.09b (well, sometimes printf will mask
bugs also so I wouldn't rely on it...)

bye
-- 
Robert-Andre Croteau	BSD,MOTU		robert@unix.sh
Services Conseils Informatiques MOTU Inc. 	robert@motu.ca
(514) 465-3057					rcroteau@videotron.ca
http://www.motu.ca/                             http://www.bb4.com
	Si le bonheur ne s'achete pas alors louez le.
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