[ros-users] Debuggin ROS_COMM deserializer

Hello all.

I built ros from source on an ARM armv5tejl platform.
Compilation, linking and running nodes all work, but messages have problems:

|[ERROR] [1353939756.715474051]: Exception thrownwhen deserializing message of length[164] from [/add_two_ints_server]: Buffer Overrun

|

Now having checked /message_deserializer.cpp/ I know where this error
originates, but I don't have any means to debug this.
The problem happens when any node is run on the arm platform: meaning
that if I run the core on my laptop together with a listener, and the
talker on the arm, the /rosout reports this error, and the same if any
of these three nodes is run on the arm.

If all nodes are run on x86 computers on the same network, everything is
fine.

So I continued searching for a byte-buffer as the buffer mentioned in 
the serialization protocol is a message buffer and overrunning that 
would mean dropping messages, not the inability to deserialize.
So in topic_manager.cpp  line 638 finally a buffer appears whose size is 
parametrized on header_bytes.size.
Header_bytes is assigned as proto[n]
       if (proto.size() != 5 ||
           proto[1].getType() != XmlRpcValue::TypeBase64 ||
           proto[2].getType() != XmlRpcValue::TypeString ||
           proto[3].getType() != XmlRpcValue::TypeInt ||
           proto[4].getType() != XmlRpcValue::TypeInt)

in topic_manager.cpp

and
     if (proto.size() != 6 ||
         proto[1].getType() != XmlRpcValue::TypeString ||
         proto[2].getType() != XmlRpcValue::TypeInt ||
         proto[3].getType() != XmlRpcValue::TypeInt ||
         proto[4].getType() != XmlRpcValue::TypeInt ||
         proto[5].getType() != XmlRpcValue::TypeBase64)

in subscription.cpp

Following these I find XmlRpcValue.cpp and XmlRpcValue.h but I can't
find any numeric values anywhere.
So I'm guessing these values are system-dependent and fetched externally.
But from where? How can I manually set the buffer length?

Thanks and regards
||

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