/* $Id$ */ /* * Copyright (C) 2003-2006 Benny Prijono * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ #ifndef __SIP_INVITE_SESSION_H__ #define __SIP_INVITE_SESSION_H__ #include #include typedef enum pjsip_inv_state pjsip_inv_state; typedef struct pjsip_inv_session pjsip_inv_session; typedef struct pjsip_inv_callback pjsip_inv_callback; /** * This enumeration describes invite session state. */ enum pjsip_inv_state { PJSIP_INV_STATE_NULL, /**< Before INVITE is sent or received */ PJSIP_INV_STATE_CALLING, /**< After INVITE is sent */ PJSIP_INV_STATE_INCOMING, /**< After INVITE is received. */ PJSIP_INV_STATE_EARLY, /**< After response with To tag. */ PJSIP_INV_STATE_CONNECTING, /**< After 2xx is sent/received. */ PJSIP_INV_STATE_CONFIRMED, /**< After ACK is sent/received. */ PJSIP_INV_STATE_DISCONNECTED, /**< Session is terminated. */ }; /** * This structure contains callbacks to be registered by application to * receieve notifications from the framework about various events in * the invite session. */ struct pjsip_inv_callback { /** * This callback is called when the invite sesion state has changed. * Application should inspect the session state (inv_sess->state) to get * the current state of the session. * * This callback is mandatory. * * @param inv The invite session. * @param e The event which has caused the invite session's * state to change. */ void (*on_state_changed)(pjsip_inv_session *inv, pjsip_event *e); /** * This callback is called when the invite usage module has created * a new dialog and invite because of forked outgoing request. * * This callback is mandatory. * * @param inv The new invite session. * @param e The event which has caused the dialog to fork. * The type of this event can be either * PJSIP_EVENT_RX_MSG or PJSIP_EVENT_RX_200_MSG. */ void (*on_new_session)(pjsip_inv_session *inv, pjsip_event *e); /** * This callback is called whenever any transactions within the session * has changed their state. Application MAY implement this callback, * e.g. to monitor the progress of an outgoing request. * * This callback is optional. * * @param inv The invite session. * @param tsx The transaction, which state has changed. * @param e The event which has caused the transation state's * to change. */ void (*on_tsx_state_changed)(pjsip_inv_session *inv, pjsip_transaction *tsx, pjsip_event *e); /** * This callback is called when the invite session has received * new offer from peer. Application can inspect the remote offer * by calling negotiator's pjmedia_sdp_neg_get_neg_remote(), and * optionally specify a modified answer. * * This callback is optional. When it's not specified, the default * behavior is nothing. After calling this callback, the negotiator * will negotiate remote offer with session's initial capability. * * @param inv The invite session. */ void (*on_rx_offer)(pjsip_inv_session *inv); /** * This callback is called after SDP offer/answer session has completed. * The status argument specifies the status of the offer/answer, * as returned by pjmedia_sdp_neg_negotiate(). * * This callback is optional (from the point of view of the framework), * but all useful applications normally need to implement this callback. * * @param inv The invite session. * @param status The negotiation status. */ void (*on_media_update)(pjsip_inv_session *inv_ses, pj_status_t status); }; /** * This enumeration shows various options that can be applied to a session. * The bitmask combination of these options need to be specified when * creating a session. After the dialog is established (including early), * the options member of #pjsip_inv_session shows which capabilities are * common in both endpoints. */ enum pjsip_inv_option { /** * Indicate support for reliable provisional response extension */ PJSIP_INV_SUPPORT_100REL = 1, /** * Indicate support for session timer extension. */ PJSIP_INV_SUPPORT_TIMER = 2, /** * Indicate support for UPDATE method. This is automatically implied * when creating outgoing dialog. After the dialog is established, * the options member of #pjsip_inv_session shows whether peer supports * this method as well. */ PJSIP_INV_SUPPORT_UPDATE = 4, /** * Require reliable provisional response extension. */ PJSIP_INV_REQUIRE_100REL = 32, /** * Require session timer extension. */ PJSIP_INV_REQUIRE_TIMER = 64, }; /** * This structure describes the invite session. */ struct pjsip_inv_session { pj_pool_t *pool; pjsip_inv_state state; pjsip_dialog *dlg; pjsip_role_e role; unsigned options; pjmedia_sdp_neg *neg; pjsip_transaction *invite_tsx; void *mod_data[PJSIP_MAX_MODULE]; }; /** * Initialize the invite usage module and register it to the endpoint. * The callback argument contains pointer to functions to be called on * occurences of events in invite sessions. * * @param endpt The endpoint instance. * @param app_module Application module. * @param callback Callback structure. * * @return PJ_SUCCESS on success, or the appropriate error code. */ PJ_DECL(pj_status_t) pjsip_inv_usage_init(pjsip_endpoint *endpt, pjsip_module *app_module, const pjsip_inv_callback *cb); /** * Get the INVITE usage module instance. * * @return PJ_SUCCESS on success, or the appropriate error code. */ PJ_DECL(pjsip_module*) pjsip_inv_usage_instance(void); /** * Create UAC invite session for the specified dialog in dlg. * * @param dlg The dialog which will be used by this invite session. * @param local_sdp If application has determined its media capability, * it can specify the SDP here. Otherwise it can leave * this to NULL, to let remote UAS specifies an offer. * @param options The options argument is bitmask combination of SIP * features in pjsip_inv_options enumeration. * @param p_inv On successful return, the invite session will be put * in this argument. * * @return The function will return PJ_SUCCESS if it can create * the session. Otherwise the appropriate error status * will be returned on failure. */ PJ_DECL(pj_status_t) pjsip_inv_create_uac(pjsip_dialog *dlg, const pjmedia_sdp_session *local_sdp, unsigned options, pjsip_inv_session **p_inv); /** * Application SHOULD call this function upon receiving the initial INVITE * request in rdata before creating the invite session (or even dialog), * to verify that the invite session can handle the INVITE request. * This function verifies that local endpoint is capable to handle required * SIP extensions in the request (i.e. Require header) and also the media, * if media description is present in the request. * * @param rdata The incoming INVITE request. * * @param options Upon calling this function, the options argument * MUST contain the desired SIP extensions to be * applied to the session. Upon return, this argument * will contain the SIP extension that will be applied * to the session, after considering the Supported, * Require, and Allow headers in the request. * * @param sdp If local media capability has been determined, * and if application wishes to verify that it can * handle the media offer in the incoming INVITE * request, it SHOULD specify its local media capability * in this argument. * If it is not specified, media verification will not * be performed by this function. * * @param dlg If tdata is not NULL, application needs to specify * how to create the response. Either dlg or endpt * argument MUST be specified, with dlg argument takes * precedence when both are specified. * * If a dialog has been created prior to calling this * function, then it MUST be specified in dlg argument. * Otherwise application MUST specify the endpt argument * (this is useful e.g. when application wants to send * the response statelessly). * * @param endpt If tdata is not NULL, application needs to specify * how to create the response. Either dlg or endpt * argument MUST be specified, with dlg argument takes * precedence when both are specified. * * @param tdata If this argument is not NULL, this function will * create the appropriate non-2xx final response message * when the verification fails. * * @return If everything has been negotiated successfully, * the function will return PJ_SUCCESS. Otherwise it * will return the reason of the failure as the return * code. * * This function is capable to create the appropriate * response message when the verification has failed. * If tdata is specified, then a non-2xx final response * will be created and put in this argument upon return, * when the verification has failed. * * If a dialog has been created prior to calling this * function, then it MUST be specified in dlg argument. * Otherwise application MUST specify the endpt argument * (this is useful e.g. when application wants to send * the response statelessly). */ PJ_DECL(pj_status_t) pjsip_inv_verify_request( pjsip_rx_data *rdata, unsigned *options, const pjmedia_sdp_session *sdp, pjsip_dialog *dlg, pjsip_endpoint *endpt, pjsip_tx_data **tdata); /** * Create UAS invite session for the specified dialog in dlg. Application * SHOULD call the verification function before calling this function, * to ensure that it can create the session successfully. * * @param dlg The dialog to be used. * @param rdata Application MUST specify the received INVITE request * in rdata. The invite session needs to inspect the * received request to see if the request contains * features that it supports. * @param sdp If application has determined its media capability, * it can specify this capability in this argument. * If SDP is received in the initial INVITE, the UAS * capability specified in this argument doesn't have to * match the received offer; the SDP negotiator is able * to rearrange the media lines in the answer so that it * matches the offer. * @param options The options argument is bitmask combination of SIP * features in pjsip_inv_options enumeration. * @param p_inv Pointer to receive the newly created invite session. * * @return On successful, the invite session will be put in * p_inv argument and the function will return PJ_SUCCESS. * Otherwise the appropriate error status will be returned * on failure. */ PJ_DECL(pj_status_t) pjsip_inv_create_uas(pjsip_dialog *dlg, pjsip_rx_data *rdata, const pjmedia_sdp_session *local_sdp, unsigned options, pjsip_inv_session **p_inv); /** * Create the initial INVITE request for this session. This function can only * be called for UAC session. If local media capability is specified when * the invite session was created, then this function will put an SDP offer * in the outgoing INVITE request. Otherwise the outgoing request will not * contain SDP body. * * @param inv The UAC invite session. * @param p_tdata The initial INVITE request will be put in this * argument if it can be created successfully. * * @return PJ_SUCCESS if the INVITE request can be created. */ PJ_DECL(pj_status_t) pjsip_inv_invite( pjsip_inv_session *inv, pjsip_tx_data **p_tdata ); /** * Create a response message to the initial INVITE request. This function * can only be called for the initial INVITE request, as subsequent * re-INVITE request will be answered automatically. * * @param inv The UAS invite session. * @param st_code The st_code contains the status code to be sent, * which may be a provisional or final response. * @param st_text If custom status text is desired, application can * specify the text in st_text; otherwise if this * argument is NULL, default status text will be used. * @param local_sdp If application has specified its media capability * during creation of UAS invite session, the local_sdp * argument MUST be NULL. This is because application * can not perform more than one SDP offer/answer session * in a single INVITE transaction. * If application has not specified its media capability * during creation of UAS invite session, it MAY or MUST * specify its capability in local_sdp argument, * depending whether st_code indicates a 2xx final * response. * @param p_tdata Pointer to receive the response message created by * this function. * * @return PJ_SUCCESS if response message was created * successfully. */ PJ_DECL(pj_status_t) pjsip_inv_answer( pjsip_inv_session *inv, int st_code, const pj_str_t *st_text, const pjmedia_sdp_session *local_sdp, pjsip_tx_data **p_tdata ); #if 0 If we implement this, we need to send SDP answer automatically on subsequent request/response. Something like "has_answer" flag. /** * Set local answer to respond to remote SDP offer. By calling this function, * application can start SDP negotiation immediately without having to * send any request or response message. This function is normally called * when on_rx_offer() callback is called. * * @param inv The invite session. * @param sdp The SDP description which will be set as answer * to remote. */ PJ_DECL(pj_status_t) pjsip_inv_set_sdp_answer( pjsip_inv_session *inv, const pjmedia_sdp_session *sdp ); #endif /** * Create a SIP message to initiate invite session termination. Depending on * the state of the session, this function may return CANCEL request, * a non-2xx final response, or a BYE request. If the session has not answered * the incoming INVITE, this function creates the non-2xx final response with * the specified status code in st_code and optional status text in st_text. * * @param inv The invite session. * @param st_code Status code to be used for terminating the session. * @param st_text Optional status text. * @param p_tdata Pointer to receive the message to be created. * * @return PJ_SUCCESS if termination message can be created. */ PJ_DECL(pj_status_t) pjsip_inv_end_session( pjsip_inv_session *inv, int st_code, const pj_str_t *st_text, pjsip_tx_data **p_tdata ); /** * Create a re-INVITE request. * * @param inv The invite session. * @param new_contact If application wants to update its local contact and * inform peer to perform target refresh with a new * contact, it can specify the new contact in this * argument; otherwise this argument must be NULL. * @param new_offer Application MAY initiate a new SDP offer/answer * session in the request when there is no pending * answer to be sent or received. It can detect this * condition by observing the state of the SDP * negotiator of the invite session. If new offer * should be sent to remote, the offer must be specified * in this argument, otherwise it must be NULL. * @param p_tdata Pointer to receive the re-INVITE request message to * be created. * * @return PJ_SUCCESS if a re-INVITE request with the specified * characteristics (e.g. to contain new offer) can be * created. */ PJ_DECL(pj_status_t) pjsip_inv_reinvite(pjsip_inv_session *inv, const pj_str_t *new_contact, const pjmedia_sdp_session *new_offer, pjsip_tx_data **p_tdata ); /** * Create an UPDATE request. * * @param inv The invite session. * @param new_contact If application wants to update its local contact * and inform peer to perform target refresh with a new * contact, it can specify the new contact in this * argument; otherwise this argument must be NULL. * @param new_offer Application MAY initiate a new SDP offer/answer * session in the request when there is no pending answer * to be sent or received. It can detect this condition * by observing the state of the SDP negotiator of the * invite session. If new offer should be sent to remote, * the offer must be specified in this argument; otherwise * this argument must be NULL. * @param p_tdata Pointer to receive the UPDATE request message to * be created. * * @return PJ_SUCCESS if a UPDATE request with the specified * characteristics (e.g. to contain new offer) can be * created. */ PJ_DECL(pj_status_t) pjsip_inv_update ( pjsip_inv_session *inv, const pj_str_t *new_contact, const pjmedia_sdp_session *new_offer, pjsip_tx_data **p_tdata ); /** * Send request or response message in tdata. * * @param inv The invite session. * @param tdata The message to be sent. * @param token The token is an arbitrary application data that * will be put in the transaction's mod_data array, * at application module's index. Application can inspect * this value when the framework reports the completion * of the transaction that sends this message. * * @return PJ_SUCCESS if transaction can be initiated * successfully to send this message. Note that the * actual final state of the transaction itself will * be reported later, in on_tsx_state_changed() * callback. */ PJ_DECL(pj_status_t) pjsip_inv_send_msg(pjsip_inv_session *inv, pjsip_tx_data *tdata, void *token ); /** * Get the invite session for the dialog, if any. * * @param dlg The dialog which invite session is being queried. * * @return The invite session instance which has been * associated with this dialog, or NULL. */ PJ_DECL(pjsip_inv_session*) pjsip_dlg_get_inv_session(pjsip_dialog *dlg); /** * Get the invite session instance associated with transaction tsx, if any. * * @param tsx The transaction, which invite session is being * queried. * * @return The invite session instance which has been * associated with this transaction, or NULL. */ PJ_DECL(pjsip_inv_session*) pjsip_tsx_get_inv_session(pjsip_transaction *tsx); #endif /* __SIP_INVITE_SESSION_H__ */