types in "packet-tftp.c", and grab the opcode directly from the first 2
bytes of the packet, using "pntohs()" (which will also keep us from
crashing, on processors that require strict alignment, if the UDP
payload isn't aligned on a 2-byte boundary).
Also use "pntohs()" to grab the block number in data and acknowledgment
packets, for the same reason we use it to grab the opcode.
svn path=/trunk/; revision=286
reference the protocol tree with struct proto_tree and struct proto_item
objects. That way, the packet decoding source code file can be used with
non-gtk packet decoders, like a curses-based ethereal, e.g. I also re-arranged
some of the information in packet.h to more appropriate places (like other
packet-*.[ch] files).
svn path=/trunk/; revision=223
Guy Harris