The message handler plug-in process function (ffh_mh_process_function) for the message handler processes a decoded FAST message by mapping it into the publisher API.
The ffh_mh_event argument of the process function contains a pointer to the same ffh_mh_info object that was passed to the plug-in initialization function, as well as a pointer to the ffh_fast_message object that holds contents of the decoded FAST message.
The plug-in should cast ffh_mh_event->info->user_data field as a pointer to an instance of the message handling class (if one was created during the initialization), then invoke its message processing code.
In the message processing code, the plug-in maps the contents of the ffh_fast_message to RDS message(s) by invoking the publisher API.
Once the entire ffh_fast_message has been processed, the plug-in must invoke the ffh_mh_info->release_message callback specifying ffh_fast_message as the argument. This notifies the FAST feed handler that it can release any resources associated with given ffh_fast_message.