DP: Refactor responder_dp_req so it's reusable by other responders

* the internal request is now more generic and is decoupled from
  account-specific data. There is a new sss_dp_issue_request() wrapper
  that issues a BE request or registers a callback
* the public requests all use struct sss_dp_req_state as the tevent_req
  state data. This allows to report back data from the internal request
  even if the caller is just a callback notifier
* each specific request now uses an _info structure that contains all
  the data necessary to construct a DBusMessage passed to provider
* each specific request now defines a sss_dp_get_$data_msg callback that
  is called from the sss_dp_issue_request() common wraper. The purpose
  of the wrapper is to construct a DBusMessage and bind it to a DBus
  method so the message can be just sent over to back end

The miscellanous changes include:
* change SSS_DP_ constants to an enum. This way, a switch() would error
  if a value is not handled.
* rename sss_dp_get_account_int_send() to sss_dp_internal_get_send()
  request because the internal request is going to handle more than just
  account data
* the DBus return values were renamed from err_maj, err_min to dp_err
  and dp_ret respectively

1 files changed, 2 insertions, 1 deletions

diff --git a/src/responder/nss/nsssrv_services.c b/src/responder/nss/nsssrv_services.c
index 6e857ff1..cd0ec583 100644
--- a/src/responder/nss/nsssrv_services.c
+++ b/src/responder/nss/nsssrv_services.c
@@ -468,7 +468,8 @@ static void lookup_service_done(struct tevent_req *subreq)
               ("Unable to get information from Data Provider\n"
                "dp_error: [%u], errno: [%u], error_msg: [%s]\n"
                "Will try to return what we have in cache\n",
-               (unsigned int)err_maj, (unsigned int)err_min, err_msg));
+               (unsigned int)err_maj, (unsigned int)err_min,
+               err_msg ? err_msg : "none"));
     }
 
     /* Recheck the cache after the lookup.