siprec: partial cleanup when recording is dropped mid call

When the recording is dropped in the middle of the call, we should only
cleanup the B2B info, not the dialog ones, as callbacks had already been
registered. Therefore, we shall only mark the recording as not started
and do a proper cleaup at the end of the dialog

modules/siprec/siprec_logic.c

@@ -130,6 +130,12 @@ static void srec_dlg_end(struct dlg_cell *dlg, int type, struct dlg_cb_params *_
 	}
 	ss = *_params->param;
 
+	if ((ss->flags & SIPREC_STARTED) == 0) {
+		LM_DBG("sess=%p no longer in progress\n", ss);
+		/* the session was not started, or it had been deleted in the meantime */
+		return;
+	}
+
 	memset(&req, 0, sizeof(req));
 	req.et = B2B_CLIENT;
 	req.b2b_key = &ss->b2b_key;
@@ -150,6 +156,11 @@ static void srec_dlg_sequential(struct dlg_cell *dlg, int type, struct dlg_cb_pa
 	/* check which participant we are talking about */
 	ss = *_params->param;
 
+	if ((ss->flags & SIPREC_STARTED) == 0) {
+		LM_DBG("sess=%p no longer pending\n", ss);
+		return;
+	}
+
 	SIPREC_LOCK(ss);
 
 	SIPREC_REF_UNSAFE(ss);
@@ -256,6 +267,10 @@ static int srec_b2b_notify(struct sip_msg *msg, str *key, int type,
 		LM_ERR("cannot find session in parameter!\n");
 		return -1;
 	}
+	if ((ss->flags & SIPREC_STARTED) == 0) {
+		LM_DBG("sess=%p no longer active\n", ss);
+		return 0;
+	}
 	/* for now we only receive replies from SRS */
 	if (type != B2B_REPLY)
 		return srec_b2b_req(msg, ss);
@@ -345,12 +360,15 @@ static int srec_b2b_notify(struct sip_msg *msg, str *key, int type,
 	srec_rtp.copy_delete(ss->rtp, &mod_name, &ss->media);
 	srec_logic_destroy(ss);
 
-	/* we finishd everything with the dialog, let it be! */
-	srec_dlg.dlg_ctx_put_ptr(ss->dlg, srec_dlg_idx, NULL);
-	srec_dlg.dlg_unref(ss->dlg, 1);
-	ss->dlg = NULL;
-	srec_hlog(ss, SREC_UNREF, "no recording");
-	SIPREC_UNREF(ss);
+	if (!(ss->flags & SIPREC_DLG_CBS)) {
+		/* if the dialog has already been engaged, then we need to keep the
+		 * reference until the end of the dialog, where it will be cleaned up */
+		srec_dlg.dlg_ctx_put_ptr(ss->dlg, srec_dlg_idx, NULL);
+		srec_dlg.dlg_unref(ss->dlg, 1);
+		ss->dlg = NULL;
+		srec_hlog(ss, SREC_UNREF, "no recording");
+		SIPREC_UNREF(ss);
+	}
 	return ret;
 }
 
@@ -639,6 +657,8 @@ void srec_logic_destroy(struct src_sess *sess)
 	if (sess->dlginfo)
 		shm_free(sess->dlginfo);
 	sess->b2b_key.s = NULL;
+
+	sess->flags &= ~SIPREC_STARTED;
 }
 
 struct src_sess *src_get_session(void)