/* * Call this function to create request to initiate REFER subscription. * */ PJ_DEF(pj_status_t) pjsip_xfer_initiate( pjsip_evsub *sub, const pj_str_t *refer_to_uri, pjsip_tx_data **p_tdata) { pjsip_xfer *xfer; const pj_str_t refer_to = { "Refer-To", 8}; pjsip_tx_data *tdata; pjsip_generic_string_hdr *hdr; pj_status_t status; /* sub and p_tdata argument must be valid. */ PJ_ASSERT_RETURN(sub && p_tdata, PJ_EINVAL); /* Get the xfer object. */ xfer = (pjsip_xfer*) pjsip_evsub_get_mod_data(sub, mod_xfer.id); PJ_ASSERT_RETURN(xfer != NULL, PJSIP_ENOREFERSESSION); /* refer_to_uri argument MAY be NULL for subsequent REFER requests, * but it MUST be specified in the first REFER. */ PJ_ASSERT_RETURN((refer_to_uri || xfer->refer_to_uri.slen), PJ_EINVAL); /* Lock dialog. */ pjsip_dlg_inc_lock(xfer->dlg); /* Create basic REFER request */ status = pjsip_evsub_initiate(sub, pjsip_get_refer_method(), -1, &tdata); if (status != PJ_SUCCESS) goto on_return; /* Save Refer-To URI. */ if (refer_to_uri == NULL) { refer_to_uri = &xfer->refer_to_uri; } else { pj_strdup(xfer->dlg->pool, &xfer->refer_to_uri, refer_to_uri); } /* Create and add Refer-To header. */ hdr = pjsip_generic_string_hdr_create(tdata->pool, &refer_to, refer_to_uri); if (!hdr) { pjsip_tx_data_dec_ref(tdata); status = PJ_ENOMEM; goto on_return; } pjsip_msg_add_hdr(tdata->msg, (pjsip_hdr*)hdr); /* Done. */ *p_tdata = tdata; status = PJ_SUCCESS; on_return: pjsip_dlg_dec_lock(xfer->dlg); return status; }
/* * Initialize the REFER subsystem. */ PJ_DEF(pj_status_t) pjsip_xfer_init_module(pjsip_endpoint *endpt) { const pj_str_t accept = { "message/sipfrag;version=2.0", 27 }; pj_status_t status; PJ_ASSERT_RETURN(endpt != NULL, PJ_EINVAL); PJ_ASSERT_RETURN(mod_xfer.id == -1, PJ_EINVALIDOP); status = pjsip_endpt_register_module(endpt, &mod_xfer); if (status != PJ_SUCCESS) return status; status = pjsip_endpt_add_capability( endpt, &mod_xfer, PJSIP_H_ALLOW, NULL, 1, &pjsip_get_refer_method()->name); if (status != PJ_SUCCESS) return status; status = pjsip_evsub_register_pkg(&mod_xfer, &STR_REFER, PJSIP_XFER_EXPIRES, 1, &accept); if (status != PJ_SUCCESS) return status; return PJ_SUCCESS; }
/* * Create transferee (receiver of REFER request). * */ PJ_DEF(pj_status_t) pjsip_xfer_create_uas( pjsip_dialog *dlg, const pjsip_evsub_user *user_cb, pjsip_rx_data *rdata, pjsip_evsub **p_evsub ) { pjsip_evsub *sub; pjsip_xfer *xfer; const pj_str_t STR_EVENT = {"Event", 5 }; pjsip_event_hdr *event_hdr; pj_status_t status; /* Check arguments */ PJ_ASSERT_RETURN(dlg && rdata && p_evsub, PJ_EINVAL); /* Must be request message */ PJ_ASSERT_RETURN(rdata->msg_info.msg->type == PJSIP_REQUEST_MSG, PJSIP_ENOTREQUESTMSG); /* Check that request is REFER */ PJ_ASSERT_RETURN(pjsip_method_cmp(&rdata->msg_info.msg->line.req.method, pjsip_get_refer_method())==0, PJSIP_ENOTREFER); /* Lock dialog */ pjsip_dlg_inc_lock(dlg); /* The evsub framework expects an Event header in the request, * while a REFER request conveniently doesn't have one (pun intended!). * So create a dummy Event header. */ if (pjsip_msg_find_hdr_by_name(rdata->msg_info.msg, &STR_EVENT, NULL)==NULL) { event_hdr = pjsip_event_hdr_create(rdata->tp_info.pool); event_hdr->event_type = STR_REFER; pjsip_msg_add_hdr(rdata->msg_info.msg, (pjsip_hdr*)event_hdr); } /* Create server subscription */ status = pjsip_evsub_create_uas( dlg, &xfer_user, rdata, PJSIP_EVSUB_NO_EVENT_ID, &sub); if (status != PJ_SUCCESS) goto on_return; /* Create server xfer subscription */ xfer = PJ_POOL_ZALLOC_T(dlg->pool, pjsip_xfer); xfer->dlg = dlg; xfer->sub = sub; if (user_cb) pj_memcpy(&xfer->user_cb, user_cb, sizeof(pjsip_evsub_user)); /* Attach to evsub */ pjsip_evsub_set_mod_data(sub, mod_xfer.id, xfer); /* Done: */ *p_evsub = sub; on_return: pjsip_dlg_dec_lock(dlg); return status; }