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Wireshark-dev: [Wireshark-dev] Fwd: dissector question- reasembling packets

From: יוני תובל <yoni6666@xxxxxxxxx>
Date: Tue, 3 Mar 2009 11:12:08 +0200
hi ,
 
i've implemented a dissector in the development version of wireshark and it worked .
when i placed the dissectors dill's in the release version , the dissector failed .
i've debbuged it , and noticed that he function :  tcp_dissect_pdus behaves differently between both version .
 
i am using dynamic arrays in my messages .
that means that it a bit complicated to fetch the size of the packet from within the data.
therefor i am using the function like this

tcp_dissect_pdus(tvb, pinfo, tree, TRUE, fixed_size_to_ask, get_message_len, dissect_mprest_irondome_grds_interface);

and each time i get a maximum size packet, i assue that the message is greater then 1460bytes and i set fixed_size_to_ask = 1461 .
in the development version , the next tvb->length i receive is 1460 + "size of the next packet" .
in the release version i receive the actual size i asked for , 1461 .
 
does anyone know why this happens ?
 
 
 
 
thanks
 
yonatan tuval