Ethereal-cvs: [Ethereal-cvs] cvs commit: ethereal/epan packet.c packet.h plugins.c
guy 2000/11/15 01:07:48 CST
Modified files:
epan packet.c packet.h plugins.c
Log:
Add a mechanism by which a dissector can be registered by name, another
dissector can get a "handle" for that dissector by name and then call
that dissector through the handle.
This allows dissectors that can't be called through a port table or a
heuristic table to be called from other dissectors without directly
referring to the dissector function - dynamically-loaded modules, under
Windows, cannot directly call functions in the main program, and
non-plugin dissectors are in the main program and thus cannot be called
from plugin dissectors unless either
1) a pointer to the dissector is put in the Big Transfer Vector
or
2) some other mechanism for getting a pointer to the dissector
is provided.
This mechanism could also support registering old-style dissectors and
calling them from new-style dissectors without the new-style dissector
having to do the argument translation itself (I didn't add support for
registering old-style dissectors because I'd prefer to have people
tvbuffify their code if they have to register a dissector...).
It could also, in the future, perhaps support
disabling of protocols;
setting "pinfo->current_proto";
inside "call_dissector()" - and inside "{old_}dissector_try_port()" and
"{old_"dissector_try_heuristic()" - allowing a pile of stuff that
currently has to be done in every dissector be done by common code.
(I have some ideas about how to do this, by
having "proto_register_protocol()" take an abbreviation - of the
sort that would be put in, for example, "pinfo->current_proto" -
as an argument;
having the calls to register dissectors take an index returned
by "proto_register_protocol()" as an argument.
The abbreviation could be used elsewhere as well, e.g. in the "Decoding"
tab of the "Edit->Protocols" dialog box, and in a GUI for constructing
protocol filters. Watch this space.)
Make "dissect_sdp()" the first client of this mechanism; it's now static
to "packet-sdp.c", and all dissectors that call it - including the MGCP
plugin - now call it through a dissector handle fetched by
"find_dissector()". (Next step - see if Ethereal can now compile on
Windows as a result of this.)
Revision Changes Path
1.5 +80 -2 ethereal/epan/packet.c
1.5 +16 -1 ethereal/epan/packet.h
1.9 +6 -1 ethereal/epan/plugins.c