b2b_entities: trigger the E_UA_SESSION event for initial INVITEs

Add ability to trigger the E_UA_SESSION event, with the 'NEW' event
type, for initial INVITES handled with the ua_session_server_init().
This can also be suppressed with the 'n' flag.

modules/b2b_entities/doc/b2b_entities_admin.xml

@@ -418,6 +418,12 @@ modparam("b2b_entities", "ua_default_timeout", 7200)
 					<emphasis>b</emphasis> - provide the body of the SIP request/reply
 					in the <xref linkend="event_E_UA_SESSION"/> event.
 					</para></listitem>
+					<listitem><para>
+					<emphasis>n</emphasis> - do not trigger the
+					<xref linkend="event_E_UA_SESSION"/> event (with event_type
+					<emphasis>NEW</emphasis>)  for initial INVITES
+					handled with this function.
+					</para></listitem>
 				</itemizedlist>
 			</para></listitem>
 		</itemizedlist>
@@ -821,6 +827,11 @@ opensips-cli -x mi ua_session_terminate key=B2B.436.1925389.1649338095
 			<listitem><para>
 				<emphasis>event_type</emphasis> - the type of event:
 				<itemizedlist>
+					<listitem><para>
+						<emphasis>NEW</emphasis> - for initial INVITE requests,
+						handled with the <xref linkend="func_ua_session_server_init"/>
+						function.
+					</para></listitem>
 					<listitem><para>
 						<emphasis>EARLY</emphasis> - for 1xx provisional
 						responses

modules/b2b_entities/ua_api.c

@@ -153,6 +153,7 @@ static int get_all_headers(struct sip_msg *msg, str *hdrs)
 
 /* indexed with the values from enum ua_sess_event_type */
 static str event_type_str[] = {
+	str_init("NEW"),
 	str_init("EARLY"),
 	str_init("ANSWERED"),
 	str_init("REJECTED"),
@@ -465,6 +466,9 @@ static struct ua_sess_init_params *ua_parse_flags(str *s)
 		case 'b':
 			params->flags |= UA_FL_PROVIDE_BODY;
 			break;
+		case 'n':
+			params->flags |= UA_FL_SUPPRESS_NEW;
+			break;
 		default:
 			LM_WARN("unknown option `%c'\n", s->s[st]);
 		}
@@ -801,6 +805,13 @@ int b2b_ua_server_init(struct sip_msg *msg, pv_spec_t *key_spec,
 		}
 	}
 
+	if (!(init_params->flags&UA_FL_SUPPRESS_NEW) &&
+		raise_ua_sess_event(key_ret, B2B_SERVER, UA_SESS_EV_NEW,
+		init_params->flags, msg) < 0) {
+		LM_ERR("Failed to raise E_UA_SESSION event\n");
+		goto error;
+	}
+
 	pkg_free(key_ret);
 
 	return 1;

modules/b2b_entities/ua_api.h

@@ -42,10 +42,12 @@
 #define UA_FL_DISABLE_AUTO_ACK (1<<3)
 #define UA_FL_PROVIDE_HDRS     (1<<4)
 #define UA_FL_PROVIDE_BODY     (1<<5)
+#define UA_FL_SUPPRESS_NEW     (1<<6)
 
 #define UA_SESSION_DEFAULT_TIMEOUT (60 * 60 * 12)
 
 enum ua_sess_event_type {
+	UA_SESS_EV_NEW,
 	UA_SESS_EV_EARLY,
 	UA_SESS_EV_ANSWERED,
 	UA_SESS_EV_REJECTED,