gsm0808: add BSSMAP Cell Identifier matching API

Add
* osmo_lai_cmp() (to use in gsm0808_cell_id_u_matches())
* osmo_cgi_cmp() (to use in gsm0808_cell_id_u_matches())
* gsm0808_cell_id_u_match() (to re-use for single IDs and lists)
* gsm0808_cell_ids_match()
* gsm0808_cell_id_matches_list()
* Unit tests in gsm0808_test.c

Rationale:

For inter-BSC handover, it is interesting to find matches between *differing*
Cell Identity kinds. For example, if a cell as CGI 23-42-3-5, and a HO for
LAC-CI 3-5 should be handled, we need to see the match.

This is most interesting for osmo-msc, i.e. to direct the BSSMAP Handover
Request towards the correct BSC or MSC.

It is also interesting for osmo-bsc's VTY interface, to be able to manage
cells' neighbors and to trigger manual handovers by various Cell Identity
handles, as the user would expect them.

Change-Id: I5535f0d149c2173294538df75764dd181b023312

1 files changed, 2 insertions, 0 deletions

diff --git a/include/osmocom/gsm/gsm23003.h b/include/osmocom/gsm/gsm23003.h
index b5c8dcd4..b34a677b 100644
--- a/include/osmocom/gsm/gsm23003.h
+++ b/include/osmocom/gsm/gsm23003.h
@@ -122,6 +122,8 @@ static inline int osmo_mcc_from_str(const char *mcc_str, uint16_t *mcc)
 
 int osmo_mnc_cmp(uint16_t a_mnc, bool a_mnc_3_digits, uint16_t b_mnc, bool b_mnc_3_digits);
 int osmo_plmn_cmp(const struct osmo_plmn_id *a, const struct osmo_plmn_id *b);
+int osmo_lai_cmp(const struct osmo_location_area_id *a, const struct osmo_location_area_id *b);
+int osmo_cgi_cmp(const struct osmo_cell_global_id *a, const struct osmo_cell_global_id *b);
 
 int osmo_gen_home_network_domain(char *out, const struct osmo_plmn_id *plmn);
 int osmo_parse_home_network_domain(struct osmo_plmn_id *out, const char *in);