D-Modem/pjproject-2.11.1/pjsip/include/pjsip-ua/sip_100rel.h
2021-10-29 14:41:03 -04:00

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8 KiB
C

/* $Id$ */
/*
* 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_100REL_H__
#define __SIP_100REL_H__
/**
* @file sip_100rel.h
* @brief PRACK (Reliability of Provisional Responses)
*/
#include <pjsip-ua/sip_inv.h>
/**
* @defgroup PJSIP_100REL 100rel/PRACK - Reliability of Provisional Responses
* @ingroup PJSIP_HIGH_UA
* @brief PRACK - Reliability of Provisional Responses
* @{
*
* This module provides management of Reliability of Provisional Responses
* (\a 100rel and \a PRACK), as described in RFC 3262.
*
* Other than the #pjsip_100rel_init_module() function, the 100rel API
* exported by this module are not intended to be used by application, but
* rather they will be invoked by the \ref PJSIP_INV.
*
* \section pjsip_100rel_using Using Reliable Provisional Response
*
* \subsection pjsip_100rel_init Initializing 100rel Module
*
* Application must explicitly initialize 100rel module by calling
* #pjsip_100rel_init_module() in application initialization function.
*
* Once the 100rel module is initialized, it will register \a PRACK method
* in \a Allow header, and \a 100rel tag in \a Supported header.
*
* \subsection pjsip_100rel_sess Using 100rel in a Session
*
* For UAC, \a 100rel support will be enabled in the session if \a 100rel
* support is enabled in the library (default is yes).
* Outgoing INVITE request will include \a 100rel tag in \a Supported
* header and \a PRACK method in \a Allow header. When callee endpoint
* sends reliable provisional responses, the UAC will automatically send
* \a PRACK request to acknowledge the response. If callee endpoint doesn't
* send reliable provisional response, the response will be handled using
* normal, non-100rel procedure (that is, \a PRACK will not be sent).
*
* If the UAC wants to <b>mandate</b> \a 100rel support, it can specify
* #PJSIP_INV_REQUIRE_100REL in the \a options argument when calling
* #pjsip_inv_create_uac(). In this case, PJSIP will add \a 100rel tag
* in the \a Require header of the outgoing INVITE request.
*
* For UAS, if it wants to support \a 100rel but not to mandate it,
* it must specify #PJSIP_INV_SUPPORT_100REL flag in the \a options
* argument when calling #pjsip_inv_verify_request(), and pass the same
* \a options variable when calling #pjsip_inv_verify_request. If UAC had
* specified \a 100rel in it's list of extensions in \a Require header,
* the UAS will send provisional responses reliably. If UAC only listed
* \a 100rel in its \a Supported header but not in \a Require header,
* or if UAC does not list \a 100rel support at all, the UAS WILL NOT
* send provisional responses reliably.
* The snippet below can be used to accomplish this task:
*
* \verbatim
unsigned options = 0;
options |= PJSIP_INV_SUPPORT_100REL;
status = pjsip_inv_verify_request(rdata, &options, answer, NULL,
endpt, &resp);
if (status != PJ_SUCCESS) {
// INVITE request cannot be handled.
// Reject the request with the response in resp.
...
return;
}
// Create UAS dialog, populate Contact header, etc.
...
// Create UAS invite session
status = pjsip_inv_create_uas( dlg, rdata, answer, options, &inv);
..
\endverbatim
*
* For another requirement, if UAS wants to <b>mandate</b> \a 100rel support,
* it can specify #PJSIP_INV_REQUIRE_100REL flag when calling
* #pjsip_inv_verify_request(), and pass the \a options when calling
* #pjsip_inv_verify_request. In this case,
* \a 100rel extension will be used if UAC specifies \a 100rel in its
* \a Supported header. If UAC does not list \a 100rel in \a Supported header,
* the incoming INVITE request will be rejected with 421 (Extension Required)
* response. For the sample code, it should be identical to the snippet
* above, except that application must specify #PJSIP_INV_REQUIRE_100REL
* flag in the \a options instead of #PJSIP_INV_SUPPORT_100REL.
*
* For yet another requirement, if UAS <b>does not</b> want to support
* \a 100rel extension, it can reject incoming INVITE request with
* 420 (Bad Extension) response whenever incoming INVITE request has
* \a 100rel tag in its \a Require header. This can be done by specifying
* zero as the \a options when calling #pjsip_inv_verify_request().
*/
PJ_BEGIN_DECL
/**
* PRACK method constant.
* @see pjsip_get_prack_method()
*/
PJ_DECL_DATA(const pjsip_method) pjsip_prack_method;
/**
* Get #pjsip_invite_method constant.
*/
PJ_DECL(const pjsip_method*) pjsip_get_prack_method(void);
/**
* Initialize 100rel module. This function must be called once during
* application initialization, to register 100rel module to SIP endpoint.
*
* @param endpt The SIP endpoint instance.
*
* @return PJ_SUCCESS if module is successfully initialized.
*/
PJ_DECL(pj_status_t) pjsip_100rel_init_module(pjsip_endpoint *endpt);
/**
* Add 100rel support to the specified invite session. This function will
* be called internally by the invite session if it detects that the
* session needs 100rel support.
*
* @param inv The invite session.
*
* @return PJ_SUCCESS on successful.
*/
PJ_DECL(pj_status_t) pjsip_100rel_attach(pjsip_inv_session *inv);
/**
* Check if incoming response has reliable provisional response feature.
*
* @param rdata Receive data buffer containing the response.
*
* @return PJ_TRUE if the provisional response is reliable.
*/
PJ_DECL(pj_bool_t) pjsip_100rel_is_reliable(pjsip_rx_data *rdata);
/**
* Create PRACK request for the incoming reliable provisional response.
* Note that PRACK request MUST be sent using #pjsip_100rel_send_prack().
*
* @param inv The invite session.
* @param rdata The incoming reliable provisional response.
* @param p_tdata Upon return, it will be initialized with the
* PRACK request.
*
* @return PJ_SUCCESS on successful.
*/
PJ_DECL(pj_status_t) pjsip_100rel_create_prack(pjsip_inv_session *inv,
pjsip_rx_data *rdata,
pjsip_tx_data **p_tdata);
/**
* Send PRACK request.
*
* @param inv The invite session.
* @param tdata The PRACK request.
*
* @return PJ_SUCCESS on successful.
*/
PJ_DECL(pj_status_t) pjsip_100rel_send_prack(pjsip_inv_session *inv,
pjsip_tx_data *tdata);
/**
* Handle incoming PRACK request.
*
* @param inv The invite session.
* @param rdata Incoming PRACK request.
*
* @return PJ_SUCCESS on successful.
*/
PJ_DECL(pj_status_t) pjsip_100rel_on_rx_prack(pjsip_inv_session *inv,
pjsip_rx_data *rdata);
/**
* Transmit INVITE response (provisional or final) reliably according to
* 100rel specification. The 100rel module will take care of retransmitting
* or enqueueing the response according to the current state of the
* reliable response processing. This function will be called internally
* by invite session.
*
* @param inv The invite session.
* @param tdata The INVITE response.
*
* @return PJ_SUCCESS on successful.
*/
PJ_DECL(pj_status_t) pjsip_100rel_tx_response(pjsip_inv_session *inv,
pjsip_tx_data *tdata);
/**
* Notify 100rel module that the invite session has been disconnected.
*
* @param inv The invite session.
*
* @return PJ_SUCCESS on successful.
*/
PJ_DECL(pj_status_t) pjsip_100rel_end_session(pjsip_inv_session *inv);
PJ_END_DECL
/**
* @}
*/
#endif /* __SIP_100REL_H__ */