Make compatible with private sigtran structs

Adjust OsmoMSC to build with newer versions of libosmo-sigtran, where
several structs were made private. This based on Pau's patch
9faff776 ("Use new libosmo-sigtran API osmo_ss7_as_select_asp()").

Related: OS#6617
Change-Id: I6c7d5119174de8d37d1ebe2b47793f9b89cc903c

configure.ac

@@ -226,6 +226,18 @@ AM_CONDITIONAL([HAVE_SYSTEMD], [test "x$with_systemdsystemunitdir" != "xno"])
 AC_MSG_RESULT([CFLAGS="$CFLAGS"])
 AC_MSG_RESULT([CPPFLAGS="$CPPFLAGS"])
 
+# OS#6617: check if libosmo-sigtran has private structs
+# We need to use grep here, can't set the includedir with AC_CHECK_DECL.
+m="OS#6617: checking whether libosmo-sigtran has private structs..."
+h="$($PKG_CONFIG --variable=includedir libosmo-sigtran)/osmocom/sigtran/osmo_ss7.h"
+f=osmo_ss7_instance_get_primary_pc
+if grep -q "$f" "$h"; then
+	echo "$m yes ($f in $h)"
+	AC_DEFINE(SIGTRAN_PRIVATE_STRUCTS, [1], ["OS#6617"])
+else
+	echo "$m no ($f not in $h)"
+fi
+
 dnl Generate the output
 AM_CONFIG_HEADER(config.h)
 

src/libmsc/transaction.c

@@ -17,6 +17,7 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  *
  */
+#include "config.h"
 
 #include <osmocom/msc/transaction.h>
 #include <osmocom/msc/gsm_data.h>
@@ -124,7 +125,12 @@ struct osmo_lcls *trans_lcls_compose(const struct gsm_trans *trans, bool use_lac
 
 	struct osmo_ss7_instance *ss7 = osmo_sccp_get_ss7(trans->net->a.sri->sccp);
 	struct osmo_lcls *lcls;
+#ifdef SIGTRAN_PRIVATE_STRUCTS
+	const struct osmo_ss7_pc_fmt *pc_fmt = osmo_ss7_instance_get_pc_fmt(ss7);
+	uint8_t w = osmo_ss7_pc_width(pc_fmt);
+#else
 	uint8_t w = osmo_ss7_pc_width(&ss7->cfg.pc_fmt);
+#endif
 
 	if (!trans->net->lcls_permitted) {
 		LOGP(DCC, LOGL_NOTICE, "LCLS disabled globally\n");
@@ -150,7 +156,12 @@ struct osmo_lcls *trans_lcls_compose(const struct gsm_trans *trans, bool use_lac
 	LOGP(DCC, LOGL_INFO, "LCLS: using %u bits (%u bytes) for node ID\n", w, w / 8);
 
 	lcls->gcr.net_len = 3;
+
+#ifdef SIGTRAN_PRIVATE_STRUCTS
+	lcls->gcr.node = osmo_ss7_instance_get_primary_pc(ss7);
+#else
 	lcls->gcr.node = ss7->cfg.primary_pc;
+#endif
 
 	/* net id from Q.1902.3 3-5 bytes, this function gives 3 bytes exactly */
 	osmo_plmn_to_bcd(lcls->gcr.net, &trans->msc_a->via_cell.lai.plmn);

src/osmo-msc/msc_main.c

@@ -803,10 +803,21 @@ TODO: we probably want some of the _net_ ctrl commands from bsc_base_ctrl_cmds_i
 		ret = 10;
 		goto error;
 	}
+
+#ifdef SIGTRAN_PRIVATE_STRUCTS
+	const struct osmo_ss7_instance *ss7;
+	ss7 = osmo_sccp_get_ss7(msc_network->a.sri->sccp);
+	OSMO_ASSERT(ss7);
+	LOGP(DMSC, LOGL_NOTICE, "A-interface: SCCP user %s, cs7-instance %u (%s)\n",
+	     osmo_sccp_user_name(msc_network->a.sri->scu),
+	     osmo_ss7_instance_get_id(ss7),
+	     osmo_ss7_instance_get_name(ss7));
+#else
 	LOGP(DMSC, LOGL_NOTICE, "A-interface: SCCP user %s, cs7-instance %u (%s)\n",
 	     osmo_sccp_user_name(msc_network->a.sri->scu),
 	     osmo_sccp_get_ss7(msc_network->a.sri->sccp)->cfg.id,
 	     osmo_sccp_get_ss7(msc_network->a.sri->sccp)->cfg.name);
+#endif
 
 #ifdef BUILD_IU
 	talloc_asn1_ctx = talloc_named_const(tall_msc_ctx, 0, "asn1");
@@ -823,11 +834,18 @@ TODO: we probably want some of the _net_ ctrl commands from bsc_base_ctrl_cmds_i
 	/* Compatibility with legacy osmo-hnbgw that was unable to properly handle RESET messages. */
 	msc_network->iu.sri->ignore_missing_reset = true;
 
+#ifdef SIGTRAN_PRIVATE_STRUCTS
+	LOGP(DMSC, LOGL_NOTICE, "Iu-interface: SCCP user %s, cs7-instance %u (%s)\n",
+	     osmo_sccp_user_name(msc_network->iu.sri->scu),
+	     osmo_ss7_instance_get_id(ss7),
+	     osmo_ss7_instance_get_name(ss7));
+#else
 	LOGP(DMSC, LOGL_NOTICE, "Iu-interface: SCCP user %s, cs7-instance %u (%s)\n",
 	     osmo_sccp_user_name(msc_network->iu.sri->scu),
 	     osmo_sccp_get_ss7(msc_network->iu.sri->sccp)->cfg.id,
 	     osmo_sccp_get_ss7(msc_network->iu.sri->sccp)->cfg.name);
 #endif
+#endif /* BUILD_IU */
 
 	/* Init RRLP handlers */
 	msc_rrlp_init();