pjproject/pjsip/include/pjsip/sip_dialog.h

606 lines
21 KiB
C

/* $Id$ */
/*
* Copyright (C) 2003-2007 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 __PJSIP_SIP_DIALOG_H__
#define __PJSIP_SIP_DIALOG_H__
/**
* @file dialog.h
* @brief SIP Dialog abstraction
*/
#include <pjsip/sip_msg.h>
#include <pjsip/sip_auth.h>
#include <pjsip/sip_errno.h>
#include <pjsip/sip_transport.h>
#include <pj/sock.h>
#include <pj/assert.h>
/**
* @defgroup PJSIP_DIALOG Base Dialog
* @ingroup PJSIP_UA
* @brief The base dialog framework to support dialog usages.
* @{
*
* The base dialog framework provides management for base dialog
* properties such as <b>From</b> header, <b>To</b> header, <b>CSeq</b>
* sequencing, <b>Call-ID</b> header, <b>Contact</b> header management,
* dialog <b>route-set</b> management, and common <b>authentication</b>.
* This basic dialog functionality will be shared by all <b>dialog
* usages</b> of a particular dialog.
*
* 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.
*
* Application MUST initialize the user agent layer module by calling
* #pjsip_ua_init_module() before using any of the dialog API, and link
* the application with with <b>pjsip-core</b> library.
*/
PJ_BEGIN_DECL
/**
* This structure is used to describe dialog's participants, which in this
* case is local party (i.e. us) and remote party.
*/
typedef struct pjsip_dlg_party
{
pjsip_fromto_hdr *info; /**< From/To header, inc tag. */
pj_str_t info_str; /**< String rep of info header. */
pj_uint32_t tag_hval; /**< Hashed value of the tag. */
pjsip_contact_hdr *contact; /**< Contact header. */
pj_int32_t first_cseq;/**< First CSeq seen. */
pj_int32_t cseq; /**< Next sequence number. */
} pjsip_dlg_party;
/**
* Dialog state.
*/
typedef enum pjsip_dialog_state
{
/** Dialog is not established. */
PJSIP_DIALOG_STATE_NULL,
/** Dialog has been established (probably early) */
PJSIP_DIALOG_STATE_ESTABLISHED
} pjsip_dialog_state;
/**
* This structure describes the dialog structure. Application MUST NOT
* try to SET the values here directly, but instead it MUST use the
* appropriate dialog API. The dialog declaration only needs to be made
* visible because other PJSIP modules need to see it (e.g. INVITE session,
* the event framework, etc.).
*
* Application MAY READ the dialog contents directly after it acquires
* dialog lock.
*
* To acquire dialog lock, use #pjsip_dlg_inc_lock(), and to release it,
* use #pjsip_dlg_dec_lock(). DO NOT USE pj_mutex_lock()/pj_mutex_unlock()
* on the dialog's mutex directly, because this will not protect against
* dialog being destroyed.
*/
struct pjsip_dialog
{
/** The dialog set list. */
PJ_DECL_LIST_MEMBER(pjsip_dialog);
/* Dialog's system properties. */
char obj_name[PJ_MAX_OBJ_NAME]; /**< Standard id. */
pj_pool_t *pool; /**< Dialog's pool. */
pj_mutex_t *mutex_; /**< Dialog's mutex. Do not call!!
Use pjsip_dlg_inc_lock() instead! */
pjsip_user_agent *ua; /**< User agent instance. */
pjsip_endpoint *endpt; /**< Endpoint instance. */
/** The dialog set which this dialog belongs (opaque type). */
void *dlg_set;
/* Dialog's session properties. */
pjsip_dialog_state state; /**< Dialog state. */
pjsip_uri *target; /**< Current target. */
pjsip_hdr inv_hdr; /**< Headers from hparam in dest URL */
pjsip_dlg_party local; /**< Local party info. */
pjsip_dlg_party remote; /**< Remote party info. */
pjsip_role_e role; /**< Initial role. */
pj_bool_t uac_has_2xx;/**< UAC has received 2xx response? */
pj_bool_t secure; /**< Use secure transport? */
pj_bool_t add_allow; /**< Add Allow header in requests? */
pjsip_cid_hdr *call_id; /**< Call-ID header. */
pjsip_route_hdr route_set; /**< Route set. */
pjsip_auth_clt_sess auth_sess; /**< Client authentication session. */
/** Session counter. */
int sess_count; /**< Number of sessions. */
/** Transaction counter. */
int tsx_count; /**< Number of pending transactions. */
/** Transport selector. */
pjsip_tpselector tp_sel;
/* Dialog usages. */
unsigned usage_cnt; /**< Number of registered usages. */
pjsip_module *usage[PJSIP_MAX_MODULE]; /**< Array of usages,
priority sorted */
/** Module specific data. */
void *mod_data[PJSIP_MAX_MODULE]; /**< Module data. */
};
/**
* This utility function returns PJ_TRUE if the specified method is a
* dialog creating request. This method property is used to determine
* whether Contact header should be included in outgoing request.
*
* @param m The SIP method.
*
* @return PJ_TRUE if the method creates a dialog.
*/
PJ_DECL(pj_bool_t) pjsip_method_creates_dialog(const pjsip_method *m);
/**
* Create a new dialog and return the instance in p_dlg parameter.
* After creating the dialog, application can add modules as dialog usages
* by calling #pjsip_dlg_add_usage().
*
* If the request has To tag parameter, dialog's local tag will be initialized
* from this value. Otherwise a globally unique id generator will be invoked to
* create dialog's local tag.
*
* This function also initializes the dialog's route set based on the
* Record-Route headers in the request, if present.
*
* Note that initially, the session count in the dialog will be initialized
* to zero.
*
* @param ua The user agent module instance.
* @param local_uri Dialog local URI (i.e. From header).
* @param local_contact_uri Optional dialog local Contact URI.
* If this argument is NULL, the Contact will be
* taken from the local URI.
* @param remote_uri Dialog remote URI (i.e. To header).
* @param target Optional initial remote target. If this argument
* is NULL, the initial target will be set to
* remote URI.
* @param p_dlg Pointer to receive the dialog.
*
* @return PJ_SUCCESS on success.
*/
PJ_DECL(pj_status_t) pjsip_dlg_create_uac( pjsip_user_agent *ua,
const pj_str_t *local_uri,
const pj_str_t *local_contact_uri,
const pj_str_t *remote_uri,
const pj_str_t *target,
pjsip_dialog **p_dlg);
/**
* Initialize UAS dialog from the information found in the incoming request
* that creates a dialog (such as INVITE, REFER, or SUBSCRIBE), and set the
* local Contact to contact. If contact is not specified, the local contact
* is initialized from the URI in the To header in the request.
*
* This function will also create UAS transaction for the incoming request,
* and associate the transaction to the rdata. Application can query the
* transaction used to handle this request by calling #pjsip_rdata_get_tsx()
* after this function returns.
*
* Note that initially, the session count in the dialog will be initialized
* to zero.
*
*
* @param ua The user agent module instance.
* @param rdata The incoming request that creates the dialog,
* such as INVITE, SUBSCRIBE, or REFER.
* @param contact Optional URI to be used as local Contact. If
* this argument is NULL, the local contact will be
* initialized from the value of To header in the
* request.
* @param p_dlg Pointer to receive the dialog.
*
* @return PJ_SUCCESS on success.
*/
PJ_DECL(pj_status_t) pjsip_dlg_create_uas( pjsip_user_agent *ua,
pjsip_rx_data *rdata,
const pj_str_t *contact,
pjsip_dialog **p_dlg);
/**
* Lock/bind dialog to a specific transport/listener. This is optional,
* as normally transport will be selected automatically based on the
* destination of messages upon resolver completion. When the dialog is
* explicitly bound to the specific transport/listener, all transactions
* originated by this dialog will use the specified transport/listener
* when sending outgoing requests.
*
* Note that this doesn't affect the Contact header generated by this
* dialog. Application must manually update the Contact header if
* necessary, to adjust the address according to the transport being
* selected.
*
* @param dlg The dialog instance.
* @param sel Transport selector containing the specification of
* transport or listener to be used by this dialog
* to send requests.
*
* @return PJ_SUCCESS on success, or the appropriate error code.
*/
PJ_DECL(pj_status_t) pjsip_dlg_set_transport(pjsip_dialog *dlg,
const pjsip_tpselector *sel);
/**
* Create a new (forked) dialog on receipt on forked response in rdata.
* The new dialog will be created from original_dlg, except that it will have
* new remote tag as copied from the To header in the response. Upon return,
* the new_dlg will have been registered to the user agent. Applications just
* need to add modules as dialog's usages.
*
* Note that initially, the session count in the dialog will be initialized
* to zero.
*
* @param original_dlg The original UAC dialog.
* @param rdata The incoming forked response message.
* @param new_dlg Pointer to receive the new dialog.
*
* @return PJ_SUCCESS on success.
*/
PJ_DECL(pj_status_t) pjsip_dlg_fork(const pjsip_dialog *original_dlg,
const pjsip_rx_data *rdata,
pjsip_dialog **new_dlg );
/**
* Forcefully terminate the dialog. Application can only call this function
* when there is no session associated to the dialog. If there are sessions
* that use this dialog, this function will refuse to terminate the dialog.
* For this case, application MUST call the appropriate termination function
* for each dialog session (e.g. #pjsip_inv_terminate() to terminate INVITE
* session).
*
* @param dlg The dialog.
*
* @return PJ_SUCCESS if dialog has been terminated.
*/
PJ_DECL(pj_status_t) pjsip_dlg_terminate( pjsip_dialog *dlg );
/**
* Set dialog's initial route set to route_set list. This can only be called
* for UAC dialog, before any request is sent. After dialog has been
* established, the route set can not be changed.
*
* For UAS dialog,the route set will be initialized in pjsip_dlg_create_uas()
* from the Record-Route headers in the incoming request.
*
* The route_set argument is standard list of Route headers (i.e. with
* sentinel).
*
* @param dlg The UAC dialog.
* @param route_set List of Route header.
*
* @return PJ_SUCCESS on success.
*/
PJ_DECL(pj_status_t) pjsip_dlg_set_route_set( pjsip_dialog *dlg,
const pjsip_route_hdr *route_set );
/**
* Increment the number of sessions in the dialog. Note that initially
* (after created) the dialog has the session counter set to zero.
*
* @param dlg The dialog.
* @param mod The module that increments the session counter.
*
* @return PJ_SUCCESS on success.
*/
PJ_DECL(pj_status_t) pjsip_dlg_inc_session( pjsip_dialog *dlg,
pjsip_module *mod);
/**
* Decrement the number of sessions in the dialog. Once the session counter
* reach zero and there is no pending transaction, the dialog will be
* destroyed. Note that this function may destroy the dialog immediately
* if there is no pending transaction when this function is called.
*
* @param dlg The dialog.
* @param mod The module that decrements the session counter.
*
* @return PJ_SUCCESS on success.
*/
PJ_DECL(pj_status_t) pjsip_dlg_dec_session( pjsip_dialog *dlg,
pjsip_module *mod);
/**
* Add a module as dialog usage, and optionally set the module specific data.
*
* @param dlg The dialog.
* @param module The module to be registered as dialog usage.
* @param mod_data Optional arbitrary data to be attached to dialog's
* mod_data array at the module's index.
*
* @return PJ_SUCCESS on success.
*/
PJ_DECL(pj_status_t) pjsip_dlg_add_usage( pjsip_dialog *dlg,
pjsip_module *module,
void *mod_data );
/**
* Attach module specific data to the dialog. Application can also set
* the value directly by accessing dlg->mod_data[module_id].
*
* @param dlg The dialog
* @param mod_id The ID of the module from which the data is to be
* set to the dialog.
* @param data Arbitrary data.
*
* @return PJ_SUCCESS on success.
*/
PJ_DECL(pj_status_t) pjsip_dlg_set_mod_data( pjsip_dialog *dlg,
int mod_id,
void *data );
/**
* Get module specific data previously attached to the dialog. Application
* can also get value directly by accessing dlg->mod_data[module_id].
*
* @param dlg The dialog
* @param mod_id The ID of the module from which the data is to be
* retrieved from the dialog.
*
* @return The data that was previously set, or NULL.
*/
PJ_DECL(void*) pjsip_dlg_get_mod_data( pjsip_dialog *dlg,
int mod_id);
/**
* Lock dialog and increment session counter termporarily, to prevent it
* from being destroyed.
*
* @param dlg The dialog.
*/
PJ_DECL(void) pjsip_dlg_inc_lock( pjsip_dialog *dlg );
/**
* Try to acquire dialog's lock, but return immediately if lock can not
* be acquired.
*
* @param dlg The dialog.
*
* @return PJ_SUCCESS if lock has been acquired.
*/
PJ_DECL(pj_status_t) pjsip_dlg_try_inc_lock( pjsip_dialog *dlg );
/**
* Unlock dialog and decrement temporary session counter. After this function
* is called, dialog may be destroyed.
*
* @param dlg The dialog.
*/
PJ_DECL(void) pjsip_dlg_dec_lock( pjsip_dialog *dlg );
/**
* Get the dialog instance in the incoming rdata. If an incoming message
* matches an existing dialog, the user agent must have put the matching
* dialog instance in the rdata, or otherwise this function will return
* NULL if the message didn't match any existing dialog.
*
* This function can only be called after endpoint distributes the message
* to the transaction layer or UA layer. In other words, application can
* only call this function in the context of module that runs in priority
* number higher than PJSIP_MOD_PRIORITY_UA_PROXY_LAYER.
*
* @param rdata Incoming message buffer.
*
* @return The dialog instance that "owns" the message.
*/
PJ_DECL(pjsip_dialog*) pjsip_rdata_get_dlg( pjsip_rx_data *rdata );
/**
* Get the associated dialog for the specified transaction, if any.
*
* @param tsx The transaction.
*
* @return The dialog instance which has been registered
* to the transaction as transaction user, or
* NULL if the transaction is outside any dialogs.
*/
PJ_DECL(pjsip_dialog*) pjsip_tsx_get_dlg( pjsip_transaction *tsx );
/**
* Create a basic/generic request with the specified method and optionally
* specify the cseq. Use value -1 for cseq to have the dialog automatically
* put next cseq number for the request. Otherwise for some requests,
* e.q. CANCEL and ACK, application must put the CSeq in the original
* INVITE request as the parameter.
*
* This function will also put Contact header where appropriate.
*
* @param dlg The dialog instance.
* @param method The method of the request.
* @param cseq Optional CSeq, which only needs to be specified
* when creating ACK and CANCEL. For other requests,
* specify -1 to use dialog's internal counter.
* @param tdata Pointer to receive the request's transmit
* data buffer.
*
* @return PJ_SUCCESS on success.
*/
PJ_DECL(pj_status_t) pjsip_dlg_create_request( pjsip_dialog *dlg,
const pjsip_method *method,
int cseq,
pjsip_tx_data **tdata);
/**
* Send request message to remote peer. If the request is not an ACK request,
* the dialog will send the request statefully, by creating an UAC transaction
* and send the request with the transaction.
*
* Also when the request is not ACK or CANCEL, the dialog will increment its
* local cseq number and update the cseq in the request according to dialog's
* cseq.
*
* If p_tsx is not null, this argument will be set with the transaction
* instance that was used to send the request.
*
* This function will decrement the transmit data's reference counter
* regardless the status of the operation.
*
* @param dlg The dialog.
* @param tdata The request message to be sent.
* @param mod_data_id Optional module data index to put an optional data
* into the transaction. If no module data is to be
* attached, this value should be -1.
* @param mod_data Optional module data to be attached to the
* transaction at mod_data_id index.
*
* @return PJ_SUCCESS on success.
*/
PJ_DECL(pj_status_t) pjsip_dlg_send_request ( pjsip_dialog *dlg,
pjsip_tx_data *tdata,
int mod_data_id,
void *mod_data);
/**
* Create a response message for the incoming request in rdata with status
* code st_code and optional status text st_text. This function is different
* than endpoint's API #pjsip_endpt_create_response() in that the dialog
* function adds Contact header and Record-Routes headers in the response
* where appropriate.
*
* @param dlg The dialog.
* @param rdata The incoming request message for which the
* response will be created.
* @param st_code Status code.
* @param st_text Optional string for custom status reason text.
* @param tdata Pointer to receive the response message transmit
* data buffer.
*
* @return PJ_SUCCESS on success.
*/
PJ_DECL(pj_status_t) pjsip_dlg_create_response( pjsip_dialog *dlg,
pjsip_rx_data *rdata,
int st_code,
const pj_str_t *st_text,
pjsip_tx_data **tdata);
/**
* Modify previously sent response with other status code. Contact header
* will be added when appropriate.
*
* @param dlg The dialog.
* @param tdata The transmit data buffer containing response
* message to be modified.
* @param st_code New status code to be set.
* @param st_text Optional string for custom status reason text.
*
* @return PJ_SUCCESS on success.
*/
PJ_DECL(pj_status_t) pjsip_dlg_modify_response( pjsip_dialog *dlg,
pjsip_tx_data *tdata,
int st_code,
const pj_str_t *st_text);
/**
* Send response message statefully. The transaction instance MUST be the
* transaction that was reported on on_rx_request() callback.
*
* This function decrements the transmit data's reference counter regardless
* the status of the operation.
*
* @param dlg The dialog.
* @param tsx The UAS transaction associated with the incoming
* request. If the request is within a dialog, or
* a dialog has been created for the request that
* creates the dialog, application can get the
* transaction instance for the request by calling
* #pjsip_rdata_get_tsx().
* @param tdata Response message to be sent.
*
* @return PJ_SUCCESS on success.
*/
PJ_DECL(pj_status_t) pjsip_dlg_send_response( pjsip_dialog *dlg,
pjsip_transaction *tsx,
pjsip_tx_data *tdata);
/**
* This composite function sends response message statefully to an incoming
* request message inside dialog.
*
* @param dlg The endpoint instance.
* @param rdata The incoming request message.
* @param st_code Status code of the response.
* @param st_text Optional status text of the response.
* @param hdr_list Optional header list to be added to the response.
* @param body Optional message body to be added to the response.
*
* @return PJ_SUCCESS if response message has successfully been
* sent.
*/
PJ_DECL(pj_status_t) pjsip_dlg_respond( pjsip_dialog *dlg,
pjsip_rx_data *rdata,
int st_code,
const pj_str_t *st_text,
const pjsip_hdr *hdr_list,
const pjsip_msg_body *body );
/**
* @}
*/
/*
* Internal (called by sip_ua_layer.c)
*/
/* Receives transaction event (called by user_agent module) */
void pjsip_dlg_on_tsx_state( pjsip_dialog *dlg,
pjsip_transaction *tsx,
pjsip_event *e );
void pjsip_dlg_on_rx_request( pjsip_dialog *dlg,
pjsip_rx_data *rdata );
void pjsip_dlg_on_rx_response( pjsip_dialog *dlg,
pjsip_rx_data *rdata );
PJ_END_DECL
#endif /* __PJSIP_SIP_DIALOG_H__ */