[PD] tcpserver crashes on the 34th client connection

[Antoine Villeret]

shame on me,

there does exist a [port <port_number>( message in iemnet's tcpserver with
which I can change the port on the fly
the rightmost outlet sends [port -1( if binding failed

but this is not explained in the help patch, I should have to go through
the code to see that
could I push an updated version of help patch to the SVN ?
here it is attached

kind regards

a

--
do it yourself
http://antoine.villeret.free.fr


2013/5/20 Antoine Villeret <antoine.villeret at gmail.com>

> Hi Martin,
>
> Thanks for your reply.
>
> For now, I increase the MAX_CONNECT value and I also make each client
> disconnecting after they receive expected data, and they connect again if
> needed.
>
> But I experience another issue.
> If Pd crashes for any reason, the socket stay in a TIME_WAIT state and if
> Pd restarts asap, the port may not be available and thus tcpserver can't
> bind to it.
> I have to wait until the end of TIME-OUT before restarting Pd.
> I found a solution [1] (restart network service) to release the socket, so
> that tcpserver can bind to the same port again.
> But it could be good to handle this inside Pd isn't it ?
>
> So I guess two ways :
> 1- according to WMR in [1], we can set SO_REUSEADDR via setsockopt(2), but
> I don't know if this possible without lots of code rewriting...
> 2- tcpserver could also have a [bind <port_number>( message to select the
> port to bind to and send out error through its right outlet to notice if
> port is available or not, so that we can try to bind again until a port is
> available.
>
> But I'm not very familiar with sockets, so maybe I'm wrong...
>
> Cheers
>
> Antoine
>
>
> [1]
> http://serverfault.com/questions/329845/how-to-forcibly-close-a-socket-in-time-wait
>
> --
> do it yourself
> http://antoine.villeret.free.fr
>
>
> 2013/5/19 Martin Peach <martin.peach at sympatico.ca>
>
>> Yes, it seems that the routine that adds new connections doesn't check to
>> see if it has passed the number of connection slots.
>> There are MAX_CONNECT slots allocated when [tcpserver] starts.
>>
>> Thanks for finding this bug!
>>
>> There is no reason to limit the number of connections to 32 except to not
>> use up memory.
>> I think it could be changed to either dynamically add space for new
>> connections without limit or set MAX_CONNECT with a creation argument.
>>
>> For now you could recompile it with MAX_CONNECT set to another value. (At
>> some point the OS will run out of sockets. Before that Pd will slow down...)
>>
>> #define MAX_CONNECT 10000
>>
>>
>> Martin
>>
>>
>> On 2013-05-18 17:37, Antoine Villeret wrote:
>>
>>> so I reply to myself...
>>>
>>> I found this in the code of both tcpserver.c :
>>> #define MAX_CONNECT 32 /* maximum number of connections */
>>>
>>> which could be an answer embryo
>>>
>>> so, I shouldn't make more than 32 connections on the same tcpserver, ok,
>>> but why ?
>>> is there a good reason to fix this to 32 ?
>>>
>>> and this doesn't tell me why it crashes...
>>> reaching the MAX_CONNECT should handles in the code isn't it ?
>>>
>>> cheers
>>>
>>> a
>>>
>>> --
>>> do it yourself
>>> http://antoine.villeret.free.**fr <http://antoine.villeret.free.fr>
>>>
>>>
>>> 2013/5/16 Antoine Villeret <antoine.villeret at gmail.com
>>> <mailto:antoine.villeret@**gmail.com <antoine.villeret at gmail.com>>>
>>>
>>>
>>>     hi all,
>>>
>>>     I've just notice [tcpserver] crashes when the 34th client try to
>>> connect
>>>     both iemnet and mrpeach are affected
>>>
>>>     iemnet version send a strange number on the 33th connection
>>>     (like 2.8686e+07) and crashes on the 34th
>>>
>>>
>>>     here is a gdb output for iem :
>>>     Program received signal SIGSEGV, Segmentation fault.
>>>     0x00007fffcdbca746 in tcpserver_connectpoll (x=0x66994c0) at
>>>     tcpserver.c:503
>>>     503     x->x_sr[i] = y;
>>>     (gdb) watchdog: signaling pd...
>>>
>>>
>>>     and for mrpeach :
>>>     Program received signal SIGSEGV, Segmentation fault.
>>>     0x00007fffcddaf585 in tcpserver_connectpoll (x=0xadfc1c0) at
>>>     tcpserver.c:1113
>>>     1113       outlet_float(x->x_sockout, x->x_sr[i]->sr_fd);/* the
>>>     socket number */
>>>     (gdb) watchdog: signaling pd...
>>>
>>>
>>>     it happens on ubuntu 12.04 64 bit
>>>     pd 0.44.2
>>>     and SVN update today
>>>
>>>     i'm certainly doing something wrong to get this (like keeping
>>>     clients connected all the time)
>>>     but a crash is never welcome...
>>>
>>>     cheers
>>>
>>>     antoine
>>>     --
>>>     do it yourself
>>>     http://antoine.villeret.free.**fr <http://antoine.villeret.free.fr>
>>>
>>>
>>>
>>>
>>> ______________________________**_________________
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>>>
>>
>
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