BSSMAP RESET: generalize a_reset FSM

Separate the a_reset FSM implementation from BSSMAP and MSC specifics, so that
it can be re-used on the Lb interface.

Move the FSM implementation to bssmap_reset.c and tweak, to match common practices we
have generally established in our osmo_fsm implementations.

Keep a_reset.h and a_reset.c and redirect to bssmap_reset.c.

A difficulty is setting a proper logging category: the FSM definition allows
only one fixed logging category for FSM state transitions and events. Ideally,
the BSSMAP reset fsm would log on DMSC, and the BSSMAP-LE reset fsm would log
on DLCS. Since that is not possible, introduce a separate DRESET logging
category. This in fact matches an item on my wishlist, because if a given MSC
is configured but currently not connected, the previous RESET FSM would
continuously "spam" log LOGL_NOTICE messages indicating that it is resending
RESET, and I often want to silence those messages without silencing the entire
DMSC category. This is now easily possible by setting DRESET logging to
LOGL_ERROR. There is additional "link up" / "link lost" logging on DMSC, so all
interesting info is still visible on DMSC.

Change-Id: Ib3c3a163186c40a93be0dea666230431172136df

1 files changed, 2 insertions, 0 deletions

diff --git a/include/osmocom/bsc/osmo_bsc_sigtran.h b/include/osmocom/bsc/osmo_bsc_sigtran.h
index faaceb220..79afa6b41 100644
--- a/include/osmocom/bsc/osmo_bsc_sigtran.h
+++ b/include/osmocom/bsc/osmo_bsc_sigtran.h
@@ -40,6 +40,8 @@ int osmo_bsc_sigtran_init(struct llist_head *mscs);
 /* Close all open sigtran connections and channels */
 void osmo_bsc_sigtran_reset(const struct bsc_msc_data *msc);
 
+void osmo_bsc_sigtran_tx_reset(const struct bsc_msc_data *msc);
+
 /* Send reset-ack to MSC */
 void osmo_bsc_sigtran_tx_reset_ack(const struct bsc_msc_data *msc);