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diff --git a/pjsip/include/pjsip-ua/sip_inv.h b/pjsip/include/pjsip-ua/sip_inv.h new file mode 100644 index 0000000..f9f38ca --- /dev/null +++ b/pjsip/include/pjsip-ua/sip_inv.h @@ -0,0 +1,963 @@ +/* $Id: sip_inv.h 3841 2011-10-24 09:28:13Z ming $ */ +/* + * Copyright (C) 2008-2011 Teluu Inc. (http://www.teluu.com) + * Copyright (C) 2003-2008 Benny Prijono <benny@prijono.org> + * + * 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__ + +/** + * @file sip_inv.h + * @brief INVITE sessions + */ + + +#include <pjsip/sip_dialog.h> +#include <pjmedia/sdp_neg.h> + + +/** + * @defgroup PJSIP_HIGH_UA User Agent Library + * @brief Mid-level User Agent Library. + * + * This is the high level user agent library, which consists of: + * - @ref PJSIP_INV, to encapsulate INVITE sessions and SDP + * negotiation in the session, + * - @ref PJSUA_REGC, high level client registration API, and + * - @ref PJSUA_XFER. + * + * More detailed information is explained in + * <A HREF="/docs.htm">PJSIP Developer's Guide</A> + * PDF document, and readers are encouraged to read the document to + * get the concept behind dialog, dialog usages, and INVITE sessions. + * + * The User Agent Library is implemented in <b>pjsip-ua</b> static + * library. + */ + +/** + * @defgroup PJSIP_INV INVITE Session + * @ingroup PJSIP_HIGH_UA + * @brief Provides INVITE session management. + * @{ + * + * The INVITE session uses the @ref PJSIP_DIALOG framework to manage + * the underlying dialog, and is one type of usages that can use + * a particular dialog instance (other usages are event subscription, + * discussed in @ref PJSIP_EVENT_NOT). The INVITE session manages + * the life-time of the session, and also manages the SDP negotiation. + * + * Application must link with <b>pjsip-ua</b> static library to use this API. + * + * More detailed information is explained in + * <A HREF="/docs.htm">PJSIP Developer's Guide</A> + * PDF document, and readers are encouraged to read the document to + * get the concept behind dialog, dialog usages, and INVITE sessions. + * + * The INVITE session does NOT manage media. If application wants to + * use API that encapsulates both signaling and media in a very easy + * to use API, it can use @ref PJSUA_LIB for this purpose. + */ + +PJ_BEGIN_DECL + + +/** + * @see pjsip_inv_session + */ +typedef struct pjsip_inv_session pjsip_inv_session; + + +/** + * This enumeration describes invite session state. + */ +typedef 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. */ +} pjsip_inv_state; + +/** + * This structure contains callbacks to be registered by application to + * receieve notifications from the framework about various events in + * the invite session. + */ +typedef 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, or to send + * response to unhandled incoming request (such as INFO). + * + * 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 + * in "offer", and set the SDP answer with #pjsip_inv_set_sdp_answer(). + * When the application sends a SIP message to send the answer, + * this SDP answer will be negotiated with the offer, and the result + * will be sent with the SIP message. + * + * @param inv The invite session. + * @param offer Remote offer. + */ + void (*on_rx_offer)(pjsip_inv_session *inv, + const pjmedia_sdp_session *offer); + + /** + * This callback is optional, and it is used to ask the application + * to create a fresh offer, when the invite session has received + * re-INVITE without offer. This offer then will be sent in the + * 200/OK response to the re-INVITE request. + * + * If application doesn't implement this callback, the invite session + * will send the currently active SDP as the offer. + * + * @param inv The invite session. + * @param p_offer Pointer to receive the SDP offer created by + * application. + */ + void (*on_create_offer)(pjsip_inv_session *inv, + pjmedia_sdp_session **p_offer); + + /** + * 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 callback is called when the framework needs to send + * ACK request after it receives incoming 2xx response for + * INVITE. It allows application to manually handle the + * transmission of ACK request, which is required by some 3PCC + * scenarios. If this callback is not implemented, the framework + * will handle the ACK transmission automatically. + * + * When this callback is overridden, application may delay the + * sending of the ACK request (for example, when it needs to + * wait for answer from the other call leg, in 3PCC scenarios). + * + * Application creates the ACK request + * + * Once it has sent the ACK request, the framework will keep + * this ACK request in the cache. Subsequent receipt of 2xx response + * will not cause this callback to be called, and instead automatic + * retransmission of this ACK request from the cache will be done + * by the framework. + * + * This callback is optional. + */ + void (*on_send_ack)(pjsip_inv_session *inv, pjsip_rx_data *rdata); + + /** + * This callback is called when the session is about to resend the + * INVITE request to the specified target, following the previously + * received redirection response. + * + * Application may accept the redirection to the specified target + * (the default behavior if this callback is implemented), reject + * this target only and make the session continue to try the next + * target in the list if such target exists, stop the whole + * redirection process altogether and cause the session to be + * disconnected, or defer the decision to ask for user confirmation. + * + * This callback is optional. If this callback is not implemented, + * the default behavior is to NOT follow the redirection response. + * + * @param inv The invite session. + * @param target The current target to be tried. + * @param e The event that caused this callback to be called. + * This could be the receipt of 3xx response, or + * 4xx/5xx response received for the INVITE sent to + * subsequent targets, or NULL if this callback is + * called from within #pjsip_inv_process_redirect() + * context. + * + * @return Action to be performed for the target. Set this + * parameter to one of the value below: + * - PJSIP_REDIRECT_ACCEPT: immediately accept the + * redirection to this target. When set, the + * session will immediately resend INVITE request + * to the target after this callback returns. + * - PJSIP_REDIRECT_REJECT: immediately reject this + * target. The session will continue retrying with + * next target if present, or disconnect the call + * if there is no more target to try. + * - PJSIP_REDIRECT_STOP: stop the whole redirection + * process and immediately disconnect the call. The + * on_state_changed() callback will be called with + * PJSIP_INV_STATE_DISCONNECTED state immediately + * after this callback returns. + * - PJSIP_REDIRECT_PENDING: set to this value if + * no decision can be made immediately (for example + * to request confirmation from user). Application + * then MUST call #pjsip_inv_process_redirect() + * to either accept or reject the redirection upon + * getting user decision. + */ + pjsip_redirect_op (*on_redirected)(pjsip_inv_session *inv, + const pjsip_uri *target, + const pjsip_event *e); + +} pjsip_inv_callback; + + + +/** + * 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, + + /** + * Indicate support for ICE + */ + PJSIP_INV_SUPPORT_ICE = 8, + + /** + * Require ICE support. + */ + PJSIP_INV_REQUIRE_ICE = 16, + + /** + * Require reliable provisional response extension. + */ + PJSIP_INV_REQUIRE_100REL = 32, + + /** + * Require session timer extension. + */ + PJSIP_INV_REQUIRE_TIMER = 64, + + /** + * Session timer extension will always be used even when peer doesn't + * support/want session timer. + */ + PJSIP_INV_ALWAYS_USE_TIMER = 128 + +}; + +/* Forward declaration of Session Timers */ +struct pjsip_timer; + +/** + * This structure describes the invite session. + * + * Note regarding the invite session's pools. The inv_sess used to have + * only one pool, which is just a pointer to the dialog's pool. Ticket + * http://trac.pjsip.org/repos/ticket/877 has found that the memory + * usage will grow considerably everytime re-INVITE or UPDATE is + * performed. + * + * Ticket #877 then created two more memory pools for the inv_sess, so + * now we have three memory pools: + * - pool: to be used to allocate long term data for the session + * - pool_prov and pool_active: this is a flip-flop pools to be used + * interchangably during re-INVITE and UPDATE. pool_prov is + * "provisional" pool, used to allocate SDP offer or answer for + * the re-INVITE and UPDATE. Once SDP negotiation is done, the + * provisional pool will be made as the active pool, then the + * existing active pool will be reset, to release the memory + * back to the OS. So these pool's lifetime is synchronized to + * the SDP offer-answer negotiation. + * + * Higher level application such as PJSUA-LIB has been modified to + * make use of these flip-flop pools, i.e. by creating media objects + * from the provisional pool rather than from the long term pool. + * + * Other applications that want to use these pools must understand + * that the flip-flop pool's lifetimes are synchronized to the + * SDP offer-answer negotiation. + */ +struct pjsip_inv_session +{ + char obj_name[PJ_MAX_OBJ_NAME]; /**< Log identification */ + pj_pool_t *pool; /**< Long term pool. */ + pj_pool_t *pool_prov; /**< Provisional pool */ + pj_pool_t *pool_active; /**< Active/current pool*/ + pjsip_inv_state state; /**< Invite sess state. */ + pj_bool_t cancelling; /**< CANCEL requested */ + pj_bool_t pending_cancel; /**< Wait to send CANCEL*/ + pjsip_status_code cause; /**< Disconnect cause. */ + pj_str_t cause_text; /**< Cause text. */ + pj_bool_t notify; /**< Internal. */ + unsigned cb_called; /**< Cb has been called */ + pjsip_dialog *dlg; /**< Underlying dialog. */ + pjsip_role_e role; /**< Invite role. */ + unsigned options; /**< Options in use. */ + pjmedia_sdp_neg *neg; /**< Negotiator. */ + pjsip_transaction *invite_tsx; /**< 1st invite tsx. */ + pjsip_tx_data *invite_req; /**< Saved invite req */ + pjsip_tx_data *last_answer; /**< Last INVITE resp. */ + pjsip_tx_data *last_ack; /**< Last ACK request */ + pj_int32_t last_ack_cseq; /**< CSeq of last ACK */ + void *mod_data[PJSIP_MAX_MODULE];/**< Modules data. */ + struct pjsip_timer *timer; /**< Session Timers. */ +}; + + +/** + * This structure represents SDP information in a pjsip_rx_data. Application + * retrieve this information by calling #pjsip_rdata_get_sdp_info(). This + * mechanism supports multipart message body. + */ +typedef struct pjsip_rdata_sdp_info +{ + /** + * Pointer and length of the text body in the incoming message. If + * the pointer is NULL, it means the message does not contain SDP + * body. + */ + pj_str_t body; + + /** + * This will contain non-zero if an invalid SDP body is found in the + * message. + */ + pj_status_t sdp_err; + + /** + * A parsed and validated SDP body. + */ + pjmedia_sdp_session *sdp; + +} pjsip_rdata_sdp_info; + + +/** + * 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 cb Callback structure. + * + * @return PJ_SUCCESS on success, or the appropriate error code. + */ +PJ_DECL(pj_status_t) pjsip_inv_usage_init(pjsip_endpoint *endpt, + 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); + + +/** + * Dump user agent contents (e.g. all dialogs). + */ +PJ_DECL(void) pjsip_inv_usage_dump(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). + * + * @see pjsip_inv_verify_request2() + */ +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); + +/** + * Variant of #pjsip_inv_verify_request() which allows application to specify + * the parsed SDP in the \a offer argument. This is useful to avoid having to + * re-parse the SDP in the incoming request. + * + * @see pjsip_inv_verify_request() + */ +PJ_DECL(pj_status_t) pjsip_inv_verify_request2( pjsip_rx_data *rdata, + unsigned *options, + const pjmedia_sdp_session *offer, + const pjmedia_sdp_session *answer, + pjsip_dialog *dlg, + pjsip_endpoint *endpt, + pjsip_tx_data **tdata); + +/** + * Variant of #pjsip_inv_verify_request() which allows application not to + * specify the rdata (i.e. pass NULL as the rdata parameter) and specify + * the parsed SDP in the \a offer argument and a temporary pool in the + * \a tmp_pool argument. + * This is useful if application no longer has access to the rdata. + * + * @see pjsip_inv_verify_request() + */ +PJ_DECL(pj_status_t) pjsip_inv_verify_request3( pjsip_rx_data *rdata, + pj_pool_t *tmp_pool, + unsigned *options, + const pjmedia_sdp_session *offer, + const pjmedia_sdp_session *answer, + 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 local_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); + + +/** + * Forcefully terminate and destroy INVITE session, regardless of + * the state of the session. Note that this function should only be used + * when there is failure in the INVITE session creation. After the + * invite session has been created and initialized, normally application + * SHOULD use #pjsip_inv_end_session() to end the INVITE session instead. + * + * Note also that this function may terminate the underlying dialog, if + * there are no other sessions in the dialog. + * + * @param inv The invite session. + * @param st_code Status code for the reason of the termination. + * @param notify If set to non-zero, then on_state_changed() + * callback will be called. + * + * @return PJ_SUCCESS if the INVITE session has been + * terminated. + */ +PJ_DECL(pj_status_t) pjsip_inv_terminate( pjsip_inv_session *inv, + int st_code, + pj_bool_t notify ); + + +/** + * Restart UAC session and prepare the session for a new initial INVITE. + * This function can be called for example when the application wants to + * follow redirection response with a new call reusing this session so + * that the new call will have the same Call-ID and From headers. After + * the session is restarted, application may create and send a new INVITE + * request. + * + * @param inv The invite session. + * @param new_offer Should be set to PJ_TRUE since the application will + * restart the session. + * + * @return PJ_SUCCESS on successful operation. + */ +PJ_DECL(pj_status_t) pjsip_inv_uac_restart(pjsip_inv_session *inv, + pj_bool_t new_offer); + + +/** + * Accept or reject redirection response. Application MUST call this function + * after it signaled PJSIP_REDIRECT_PENDING in the \a on_redirected() + * callback, to notify the invite session whether to accept or reject the + * redirection to the current target. Application can use the combination of + * PJSIP_REDIRECT_PENDING command in \a on_redirected() callback and this + * function to ask for user permission before redirecting the call. + * + * Note that if the application chooses to reject or stop redirection (by + * using PJSIP_REDIRECT_REJECT or PJSIP_REDIRECT_STOP respectively), the + * session disconnection callback will be called before this function returns. + * And if the application rejects the target, the \a on_redirected() callback + * may also be called before this function returns if there is another target + * to try. + * + * @param inv The invite session. + * @param cmd Redirection operation. The semantic of this argument + * is similar to the description in the \a on_redirected() + * callback, except that the PJSIP_REDIRECT_PENDING is + * not accepted here. + * @param e Should be set to NULL. + * + * @return PJ_SUCCESS on successful operation. + */ +PJ_DECL(pj_status_t) pjsip_inv_process_redirect(pjsip_inv_session *inv, + pjsip_redirect_op cmd, + pjsip_event *e); + + +/** + * 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 the initial response message for the incoming INVITE request in + * rdata with status code st_code and optional status text st_text. Use + * #pjsip_inv_answer() to create subsequent response message. + */ +PJ_DECL(pj_status_t) pjsip_inv_initial_answer( pjsip_inv_session *inv, + pjsip_rx_data *rdata, + int st_code, + const pj_str_t *st_text, + const pjmedia_sdp_session *sdp, + 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 ); + + +/** + * Set local offer or answer depending on negotiator state (it may also + * create a negotiator if it doesn't exist yet). + * + * @param inv The invite session. + * @param sdp The SDP description which will be set as + * an offer/answer to remote. + * + * @return PJ_SUCCESS if local offer/answer can be accepted by + * SDP negotiator. + */ +PJ_DECL(pj_status_t) pjsip_inv_set_local_sdp(pjsip_inv_session *inv, + const pjmedia_sdp_session *sdp ); + + +/** + * Set local answer to respond to remote SDP offer, to be carried by + * subsequent response (or request). + * + * @param inv The invite session. + * @param sdp The SDP description which will be set as answer + * to remote. + * + * @return PJ_SUCCESS if local answer can be accepted by + * SDP negotiator. + */ +PJ_DECL(pj_status_t) pjsip_inv_set_sdp_answer(pjsip_inv_session *inv, + const pjmedia_sdp_session *sdp ); + + +/** + * 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, a BYE request, or even no request. + * + * For UAS, if the session has not answered the incoming INVITE, this function + * creates the non-2xx final response with the specified status code in + * \a st_code and optional status text in \a st_text. + * + * For UAC, if the original INVITE has not been answered with a final + * response, the behavior depends on whether provisional response has been + * received. If provisional response has been received, this function will + * create CANCEL request. If no provisional response has been received, the + * function will not create CANCEL request (the function will return + * PJ_SUCCESS but the \a p_tdata will contain NULL) because we cannot send + * CANCEL before receiving provisional response. If then a provisional + * response is received, the invite session will send CANCEL automatically. + * + * For both UAC and UAS, if the INVITE session has been answered with final + * response, a BYE request will be created. + * + * @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. Note + * that it's possible to receive NULL here while the + * function returns PJ_SUCCESS, see the description. + * + * @return PJ_SUCCESS if termination is initiated. + */ +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 to initiate new SDP offer. + * + * @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 offer Offer to be sent to remote. This argument is + * mandatory. + * @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 *offer, + pjsip_tx_data **p_tdata ); + + +/** + * Create an ACK request. Normally ACK request transmission is handled + * by the framework. Application only needs to use this function if it + * handles the ACK transmission manually, by overriding \a on_send_ack() + * callback in #pjsip_inv_callback. + * + * Note that if the invite session has a pending offer to be answered + * (for example when the last 2xx response to INVITE contains an offer), + * application MUST have set the SDP answer with #pjsip_create_sdp_body() + * prior to creating the ACK request. In this case, the ACK request + * will be added with SDP message body. + * + * @param inv The invite session. + * @param cseq Mandatory argument to specify the CSeq of the + * ACK request. This value MUST match the value + * of the INVITE transaction to be acknowledged. + * @param p_tdata Pointer to receive the ACK request message to + * be created. + * + * @return PJ_SUCCESS if ACK request has been created. + */ +PJ_DECL(pj_status_t) pjsip_inv_create_ack(pjsip_inv_session *inv, + int cseq, + pjsip_tx_data **p_tdata); + + +/** + * Send request or response message in tdata. + * + * @param inv The invite session. + * @param tdata The message to be sent. + * + * @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); + + +/** + * 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); + + +/** + * Get state names for INVITE session state. + * + * @param state The invite state. + * + * @return String describing the state. + */ +PJ_DECL(const char *) pjsip_inv_state_name(pjsip_inv_state state); + + +/** + * This is a utility function to create SIP body for SDP content. + * + * @param pool Pool to allocate memory. + * @param sdp SDP session to be put in the SIP message body. + * @param p_body Pointer to receive SIP message body containing + * the SDP session. + * + * @return PJ_SUCCESS on success. + */ +PJ_DECL(pj_status_t) pjsip_create_sdp_body(pj_pool_t *pool, + pjmedia_sdp_session *sdp, + pjsip_msg_body **p_body); + +/** + * Retrieve SDP information from an incoming message. Application should + * prefer to use this function rather than parsing the SDP manually since + * this function supports multipart message body. + * + * This function will only parse the SDP once, the first time it is called + * on the same message. Subsequent call on the same message will just pick + * up the already parsed SDP from the message. + * + * @param rdata The incoming message. + * + * @return The SDP info. + */ +PJ_DECL(pjsip_rdata_sdp_info*) pjsip_rdata_get_sdp_info(pjsip_rx_data *rdata); + + +PJ_END_DECL + +/** + * @} + */ + + +#endif /* __SIP_INVITE_SESSION_H__ */ |