can't process multiple messages of different lengths in one packet

[wiedmann]

FYI: there's an error in the handling that prevents multiple messages in one packet from working. The fix is easy:

1. get_message_len third parameter change to offset from tree
2. get the length from tvb:range(offset, .... instead of tvb:range(0, ....
3. change dissect_message to call tvb:len() to retrieve length instead of calling get_message_len directly

Without the fix, lppb tries to dissect each message with the length of the first in the packet because get_message_len always looks at the first bytes of the tvb.

[wiedmann]

Here's a patched version of lppb.lua.

lppb.lua.txt