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authorNeels Hofmeyr <neels@hofmeyr.de>2019-02-10 22:28:27 +0100
committerNeels Hofmeyr <neels@hofmeyr.de>2019-03-08 05:25:07 +0100
commit3a5045302f51faf104e64783977f710d36e06e3f (patch)
tree70ec869e4843a8330df1133ee617b1a7d740bd21 /src/gsm
parentd4b79c877291e58bf7fafcfd3c771c9e66fa3f5b (diff)
add gsm0808_cell_id_from_cgi(), gsm0808_cell_id_to_cgi()
CGI to Cell ID: for example, for Paging, osmo-msc has a CGI for a subscriber and needs to send out a Cell Identifier IE. Makes sense to add this conversion here. Cell ID to CGI: for a Layer 3 Complete, a subscriber sends the current cell in the form of a Cell Identifier, which we store as a CGI, if necessary enriched with the local PLMN. Add enum with bitmask values to identify parts of a CGI, for the return value of gsm0808_cell_id_to_cgi(). Can't use enum CELL_IDENT for that, because it doesn't have a value for just a PLMN (and is not a bitmask). Change-Id: Ib9af67b100c4583342a2103669732dab2e577b04
Diffstat (limited to 'src/gsm')
-rw-r--r--src/gsm/gsm0808_utils.c87
-rw-r--r--src/gsm/libosmogsm.map2
2 files changed, 89 insertions, 0 deletions
diff --git a/src/gsm/gsm0808_utils.c b/src/gsm/gsm0808_utils.c
index 54775981..dd14d3ca 100644
--- a/src/gsm/gsm0808_utils.c
+++ b/src/gsm/gsm0808_utils.c
@@ -1577,6 +1577,93 @@ int gsm0808_cell_id_matches_list(const struct gsm0808_cell_id *id, const struct
return -1;
}
+/*! Copy information from a CGI to form a Cell Identifier of the specified kind.
+ * \param [out] cid Compose new Cell Identifier here.
+ * \param [in] id_discr Which kind of Cell Identifier to compose.
+ * \param [in] cgi Cell Global Identifier to form the Cell Identifier from.
+ */
+void gsm0808_cell_id_from_cgi(struct gsm0808_cell_id *cid, enum CELL_IDENT id_discr,
+ const struct osmo_cell_global_id *cgi)
+{
+ *cid = (struct gsm0808_cell_id){
+ .id_discr = id_discr,
+ };
+
+ switch (id_discr) {
+ case CELL_IDENT_WHOLE_GLOBAL:
+ cid->id.global = *cgi;
+ return;
+
+ case CELL_IDENT_LAC_AND_CI:
+ cid->id.lac_and_ci = (struct osmo_lac_and_ci_id){
+ .lac = cgi->lai.lac,
+ .ci = cgi->cell_identity,
+ };
+ return;
+
+ case CELL_IDENT_CI:
+ cid->id.ci = cgi->cell_identity;
+ return;
+
+ case CELL_IDENT_LAI:
+ cid->id.lai_and_lac = cgi->lai;
+ return;
+
+ case CELL_IDENT_LAC:
+ cid->id.lac = cgi->lai.lac;
+ return;
+
+ case CELL_IDENT_NO_CELL:
+ case CELL_IDENT_BSS:
+ case CELL_IDENT_UTRAN_PLMN_LAC_RNC:
+ case CELL_IDENT_UTRAN_RNC:
+ case CELL_IDENT_UTRAN_LAC_RNC:
+ default:
+ return;
+ };
+}
+
+/*! Overwrite parts of cgi with values from a Cell Identifier.
+ * Place only those items given in cid into cgi, leaving other values unchanged.
+ * \param[out] cgi Cell Global Identity to write to.
+ * \param[in] cid Cell Identity to read from.
+ * \return a bitmask of items that were set: OSMO_CGI_PART_PLMN | OSMO_CGI_PART_LAC | OSMO_CGI_PART_CI; 0 if nothing was
+ * written to cgi.
+ */
+int gsm0808_cell_id_to_cgi(struct osmo_cell_global_id *cgi, const struct gsm0808_cell_id *cid)
+{
+ switch (cid->id_discr) {
+ case CELL_IDENT_WHOLE_GLOBAL:
+ *cgi = cid->id.global;
+ return OSMO_CGI_PART_PLMN | OSMO_CGI_PART_LAC | OSMO_CGI_PART_CI;
+
+ case CELL_IDENT_LAC_AND_CI:
+ cgi->lai.lac = cid->id.lac_and_ci.lac;
+ cgi->cell_identity = cid->id.lac_and_ci.ci;
+ return OSMO_CGI_PART_LAC | OSMO_CGI_PART_CI;
+
+ case CELL_IDENT_CI:
+ cgi->cell_identity = cid->id.ci;
+ return OSMO_CGI_PART_CI;
+
+ case CELL_IDENT_LAI:
+ cgi->lai = cid->id.lai_and_lac;
+ return OSMO_CGI_PART_PLMN | OSMO_CGI_PART_LAC;
+
+ case CELL_IDENT_LAC:
+ cgi->lai.lac = cid->id.lac;
+ return OSMO_CGI_PART_LAC;
+
+ case CELL_IDENT_NO_CELL:
+ case CELL_IDENT_BSS:
+ case CELL_IDENT_UTRAN_PLMN_LAC_RNC:
+ case CELL_IDENT_UTRAN_RNC:
+ case CELL_IDENT_UTRAN_LAC_RNC:
+ default:
+ return 0;
+ };
+}
+
/*! value_string[] for enum CELL_IDENT. */
const struct value_string gsm0808_cell_id_discr_names[] = {
{ CELL_IDENT_WHOLE_GLOBAL, "CGI" },
diff --git a/src/gsm/libosmogsm.map b/src/gsm/libosmogsm.map
index 2d47d7a7..3fadc5a0 100644
--- a/src/gsm/libosmogsm.map
+++ b/src/gsm/libosmogsm.map
@@ -205,6 +205,8 @@ gsm0808_dec_cell_id_list;
gsm0808_dec_cell_id_list2;
gsm0808_cell_id_list_add;
gsm0808_cell_id_to_list;
+gsm0808_cell_id_to_cgi;
+gsm0808_cell_id_from_cgi;
gsm0808_enc_cell_id;
gsm0808_dec_cell_id;
gsm0808_cell_id_name;