demarshalling messages

[Havoc Pennington]

Hi,

Dafydd Harries wrote:
> 
>  - get the marshalled form of the DBusMessage so that I can encapsulate it for
>    the network transport I'm using
> 
>  - take a marshalled message from a network transport I have and turn it into
>    a DBusMessage object so that I can send it to my local clients
> 

OK, I think I see now. You want to be able to serialize DBusMessage so 
you can put it over xmpp. As Thiago says, there is no API for that right 
now.

The simplest approach would be a two-function API to convert a 
DBusMessage to/from a byte array. The downside to this approach is that 
you could not use DBusConnection, so might end up reinventing a lot of 
that machinery - there is a lot of stuff in there, including e.g. some 
default method handlers.

The hard/complicated but possibly better approach would be to allow apps 
to provide a DBusTransport (currently a private API), which would 
involve cleaning up and opaque-ifying that private API. Then you would 
provide a DBusTransport that wraps your xmpp connection.

The bad hack approach, perhaps, would be to create a DBusConnection 
around a socketpair() pipe, and serialize/unserialize messages by 
pushing them into the pipe then reading the other end. Unfortunately I 
think the pipe transport is only compiled into the --enable-tests 
version of dbus, not the production build. But for OLPC you could do 
your own build.

It's messy any way you look at it, probably.

Havoc