pjsua_call.c

基于sip协议的网络电话源码

/* $Id: pjsua_call.c 1107 2007-03-27 10:53:57Z bennylp $ */
/* 
 * Copyright (C) 2003-2007 Benny Prijono <[e-mail]>
 *
 * 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 
 */
#include <pjsua-lib/pjsua.h>
#include <pjsua-lib/pjsua_internal.h>


#define THIS_FILE		"pjsua_call.c"


/* This callback receives notification from invite session when the
 * session state has changed.
 */
static void pjsua_call_on_state_changed(pjsip_inv_session *inv, 
					pjsip_event *e);

/* This callback is called by invite session framework when UAC session
 * has forked.
 */
static void pjsua_call_on_forked( pjsip_inv_session *inv, 
				  pjsip_event *e);

/*
 * Callback to be called when SDP offer/answer negotiation has just completed
 * in the session. This function will start/update media if negotiation
 * has succeeded.
 */
static void pjsua_call_on_media_update(pjsip_inv_session *inv,
				       pj_status_t status);

/*
 * Called when session received new offer.
 */
static void pjsua_call_on_rx_offer(pjsip_inv_session *inv,
				   const pjmedia_sdp_session *offer);

/*
 * This callback is called when transaction state has changed in INVITE
 * session. We use this to trap:
 *  - incoming REFER request.
 *  - incoming MESSAGE request.
 */
static void pjsua_call_on_tsx_state_changed(pjsip_inv_session *inv,
					    pjsip_transaction *tsx,
					    pjsip_event *e);


/* Destroy the call's media */
static pj_status_t call_destroy_media(int call_id);

/* Create inactive SDP for call hold. */
static pj_status_t create_inactive_sdp(pjsua_call *call,
				       pjmedia_sdp_session **p_answer);

/*
 * Callback called by event framework when the xfer subscription state
 * has changed.
 */
static void xfer_client_on_evsub_state( pjsip_evsub *sub, pjsip_event *event);
static void xfer_server_on_evsub_state( pjsip_evsub *sub, pjsip_event *event);

/*
 * Reset call descriptor.
 */
static void reset_call(pjsua_call_id id)
{
    pjsua_call *call = &pjsua_var.calls[id];

    call->index = id;
    call->inv = NULL;
    call->user_data = NULL;
    call->session = NULL;
    call->xfer_sub = NULL;
    call->last_code = 0;
    call->conf_slot = PJSUA_INVALID_ID;
    call->last_text.ptr = call->last_text_buf_;
    call->last_text.slen = 0;
    call->conn_time.sec = 0;
    call->conn_time.msec = 0;
    call->res_time.sec = 0;
    call->res_time.msec = 0;
}


/*
 * Init call subsystem.
 */
pj_status_t pjsua_call_subsys_init(const pjsua_config *cfg)
{
    pjsip_inv_callback inv_cb;
    unsigned i;
    const pj_str_t str_norefersub = { "norefersub", 10 };
    pj_status_t status;

    /* Init calls array. */
    for (i=0; i<PJ_ARRAY_SIZE(pjsua_var.calls); ++i)
	reset_call(i);

    /* Copy config */
    pjsua_config_dup(pjsua_var.pool, &pjsua_var.ua_cfg, cfg);

    /* Initialize invite session callback. */
    pj_bzero(&inv_cb, sizeof(inv_cb));
    inv_cb.on_state_changed = &pjsua_call_on_state_changed;
    inv_cb.on_new_session = &pjsua_call_on_forked;
    inv_cb.on_media_update = &pjsua_call_on_media_update;
    inv_cb.on_rx_offer = &pjsua_call_on_rx_offer;
    inv_cb.on_tsx_state_changed = &pjsua_call_on_tsx_state_changed;


    /* Initialize invite session module: */
    status = pjsip_inv_usage_init(pjsua_var.endpt, &inv_cb);
    PJ_ASSERT_RETURN(status == PJ_SUCCESS, status);

    /* Add "norefersub" in Supported header */
    pjsip_endpt_add_capability(pjsua_var.endpt, NULL, PJSIP_H_SUPPORTED,
			       NULL, 1, &str_norefersub);

    return status;
}


/*
 * Start call subsystem.
 */
pj_status_t pjsua_call_subsys_start(void)
{
    /* Nothing to do */
    return PJ_SUCCESS;
}


/*
 * Get maximum number of calls configured in pjsua.
 */
PJ_DEF(unsigned) pjsua_call_get_max_count(void)
{
    return pjsua_var.ua_cfg.max_calls;
}


/*
 * Get number of currently active calls.
 */
PJ_DEF(unsigned) pjsua_call_get_count(void)
{
    return pjsua_var.call_cnt;
}


/*
 * Enum calls.
 */
PJ_DEF(pj_status_t) pjsua_enum_calls( pjsua_call_id ids[],
				      unsigned *count)
{
    unsigned i, c;

    PJ_ASSERT_RETURN(ids && *count, PJ_EINVAL);

    PJSUA_LOCK();

    for (i=0, c=0; c<*count && i<pjsua_var.ua_cfg.max_calls; ++i) {
	if (!pjsua_var.calls[i].inv)
	    continue;
	ids[c] = i;
	++c;
    }

    *count = c;

    PJSUA_UNLOCK();

    return PJ_SUCCESS;
}


/*
 * Make outgoing call to the specified URI using the specified account.
 */
PJ_DEF(pj_status_t) pjsua_call_make_call( pjsua_acc_id acc_id,
					  const pj_str_t *dest_uri,
					  unsigned options,
					  void *user_data,
					  const pjsua_msg_data *msg_data,
					  pjsua_call_id *p_call_id)
{
    pjsip_dialog *dlg = NULL;
    pjmedia_sdp_session *offer;
    pjsip_inv_session *inv = NULL;
    pjsua_acc *acc;
    pjsua_call *call;
    unsigned call_id;
    pj_str_t contact;
    pjsip_tx_data *tdata;
    pj_status_t status;


    /* Check that account is valid */
    PJ_ASSERT_RETURN(acc_id>=0 || acc_id<PJ_ARRAY_SIZE(pjsua_var.acc), 
		     PJ_EINVAL);

    /* Options must be zero for now */
    PJ_ASSERT_RETURN(options == 0, PJ_EINVAL);

    /* Check arguments */
    PJ_ASSERT_RETURN(dest_uri, PJ_EINVAL);

    PJSUA_LOCK();

    acc = &pjsua_var.acc[acc_id];
    if (!acc->valid) {
	pjsua_perror(THIS_FILE, "Unable to make call because account "
		     "is not valid", PJ_EINVALIDOP);
	PJSUA_UNLOCK();
	return PJ_EINVALIDOP;
    }

    /* Find free call slot. */
    for (call_id=0; call_id<pjsua_var.ua_cfg.max_calls; ++call_id) {
	if (pjsua_var.calls[call_id].inv == NULL)
	    break;
    }

    if (call_id == pjsua_var.ua_cfg.max_calls) {
	pjsua_perror(THIS_FILE, "Error making file", PJ_ETOOMANY);
	PJSUA_UNLOCK();
	return PJ_ETOOMANY;
    }

    call = &pjsua_var.calls[call_id];

    /* Verify that destination URI is valid before calling 
     * pjsua_acc_create_uac_contact, or otherwise there  
     * a misleading "Invalid Contact URI" error will be printed
     * when pjsua_acc_create_uac_contact() fails.
     */
    if (1) {
	pj_pool_t *pool;
	pjsip_uri *uri;
	pj_str_t dup;

	pool = pjsua_pool_create("tmp-uri", 4000, 4000);
	if (!pool) {
	    pjsua_perror(THIS_FILE, "Unable to create pool", PJ_ENOMEM);
	    PJSUA_UNLOCK();
	    return PJ_ENOMEM;
	}
	
	pj_strdup_with_null(pool, &dup, dest_uri);
	uri = pjsip_parse_uri(pool, dup.ptr, dup.slen, 0);
	pj_pool_release(pool);

	if (uri == NULL) {
	    pjsua_perror(THIS_FILE, "Unable to make call", 
			 PJSIP_EINVALIDREQURI);
	    PJSUA_UNLOCK();
	    return PJSIP_EINVALIDREQURI;
	}
    }

    PJ_LOG(4,(THIS_FILE, "Making call with acc #%d to %.*s", acc_id,
	      (int)dest_uri->slen, dest_uri->ptr));

    /* Mark call start time. */
    pj_gettimeofday(&call->start_time);

    /* Reset first response time */
    call->res_time.sec = 0;

    /* Create suitable Contact header */
    status = pjsua_acc_create_uac_contact(pjsua_var.pool, &contact,
					  acc_id, dest_uri);
    if (status != PJ_SUCCESS) {
	pjsua_perror(THIS_FILE, "Unable to generate Contact header", status);
	PJSUA_UNLOCK();
	return status;
    }

    /* Create outgoing dialog: */
    status = pjsip_dlg_create_uac( pjsip_ua_instance(), 
				   &acc->cfg.id, &contact,
				   dest_uri, dest_uri, &dlg);
    if (status != PJ_SUCCESS) {
	pjsua_perror(THIS_FILE, "Dialog creation failed", status);
	PJSUA_UNLOCK();
	return status;
    }

    /* Get media capability from media endpoint: */

    status = pjmedia_endpt_create_sdp( pjsua_var.med_endpt, dlg->pool, 1, 
				       &call->skinfo, &offer);
    if (status != PJ_SUCCESS) {
	pjsua_perror(THIS_FILE, "pjmedia unable to create SDP", status);
	goto on_error;
    }

    /* Create the INVITE session: */

    status = pjsip_inv_create_uac( dlg, offer, 0, &inv);
    if (status != PJ_SUCCESS) {
	pjsua_perror(THIS_FILE, "Invite session creation failed", status);
	goto on_error;
    }


    /* Create and associate our data in the session. */

    call->inv = inv;

    dlg->mod_data[pjsua_var.mod.id] = call;
    inv->mod_data[pjsua_var.mod.id] = call;

    /* Attach user data */
    call->user_data = user_data;

    /* If account is locked to specific transport, then lock dialog
     * to this transport too.
     */
    if (acc->cfg.transport_id != PJSUA_INVALID_ID) {
	pjsip_tpselector tp_sel;

	pjsua_init_tpselector(acc->cfg.transport_id, &tp_sel);
	pjsip_dlg_set_transport(dlg, &tp_sel);
    }

    /* Set dialog Route-Set: */
    if (!pj_list_empty(&acc->route_set))
	pjsip_dlg_set_route_set(dlg, &acc->route_set);


    /* Set credentials: */
    if (acc->cred_cnt) {
	pjsip_auth_clt_set_credentials( &dlg->auth_sess, 
					acc->cred_cnt, acc->cred);
    }


    /* Create initial INVITE: */

    status = pjsip_inv_invite(inv, &tdata);
    if (status != PJ_SUCCESS) {
	pjsua_perror(THIS_FILE, "Unable to create initial INVITE request", 
		     status);
	goto on_error;
    }


    /* Add additional headers etc */

    pjsua_process_msg_data( tdata, msg_data);

    /* Must increment call counter now */
    ++pjsua_var.call_cnt;

    /* Send initial INVITE: */

    status = pjsip_inv_send_msg(inv, tdata);
    if (status != PJ_SUCCESS) {
	pjsua_perror(THIS_FILE, "Unable to send initial INVITE request", 
		     status);

	/* Upon failure to send first request, both dialog and invite 
	 * session would have been cleared.
	 */
	inv = NULL;
	dlg = NULL;
	goto on_error;
    }

    /* Done. */

    if (p_call_id)
	*p_call_id = call_id;

    PJSUA_UNLOCK();

    return PJ_SUCCESS;


on_error:
    if (inv != NULL) {
	pjsip_inv_terminate(inv, PJSIP_SC_OK, PJ_FALSE);
    } else if (dlg) {
	pjsip_dlg_terminate(dlg);
    }

    if (call_id != -1) {
	reset_call(call_id);
    }

    PJSUA_UNLOCK();
    return status;
}


/**
 * Handle incoming INVITE request.
 * Called by pjsua_core.c
 */
pj_bool_t pjsua_call_on_incoming(pjsip_rx_data *rdata)
{
    pj_str_t contact;
    pjsip_dialog *dlg = pjsip_rdata_get_dlg(rdata);
    pjsip_dialog *replaced_dlg = NULL;
    pjsip_transaction *tsx = pjsip_rdata_get_tsx(rdata);
    pjsip_msg *msg = rdata->msg_info.msg;
    pjsip_tx_data *response = NULL;
    unsigned options = 0;
    pjsip_inv_session *inv = NULL;
    int acc_id;
    pjsua_call *call;
    int call_id = -1;
    pjmedia_sdp_session *answer;
    pj_status_t status;

    /* Don't want to handle anything but INVITE */
    if (msg->line.req.method.id != PJSIP_INVITE_METHOD)
	return PJ_FALSE;

    /* Don't want to handle anything that's already associated with
     * existing dialog or transaction.
     */
    if (dlg || tsx)
	return PJ_FALSE;

    PJSUA_LOCK();

    /* Find free call slot. */
    for (call_id=0; call_id<(int)pjsua_var.ua_cfg.max_calls; ++call_id) {
	if (pjsua_var.calls[call_id].inv == NULL)
	    break;
    }

    if (call_id == (int)pjsua_var.ua_cfg.max_calls) {
	pjsip_endpt_respond_stateless(pjsua_var.endpt, rdata, 
				      PJSIP_SC_BUSY_HERE, NULL,
				      NULL, NULL);
	PJ_LOG(2,(THIS_FILE, 
		  "Unable to accept incoming call (too many calls)"));
	PJSUA_UNLOCK();
	return PJ_TRUE;
    }

    /* Clear call descriptor */
    reset_call(call_id);

    call = &pjsua_var.calls[call_id];

    /* Mark call start time. */
    pj_gettimeofday(&call->start_time);

    /* Check INVITE request for Replaces header. If Replaces header is
     * present, the function will make sure that we can handle the request.
     */
    status = pjsip_replaces_verify_request(rdata, &replaced_dlg, PJ_FALSE,
					   &response);
    if (status != PJ_SUCCESS) {
	/*
	 * Something wrong with the Replaces header.
	 */
	if (response) {
	    pjsip_response_addr res_addr;

	    pjsip_get_response_addr(response->pool, rdata, &res_addr);
	    pjsip_endpt_send_response(pjsua_var.endpt, &res_addr, response, 
				      NULL, NULL);

	} else {

	    /* Respond with 500 (Internal Server Error) */
	    pjsip_endpt_respond_stateless(pjsua_var.endpt, rdata, 500, NULL,
					  NULL, NULL);
	}

	PJSUA_UNLOCK();
	return PJ_TRUE;
    }

    /* If this INVITE request contains Replaces header, notify application
     * about the request so that application can do subsequent checking
     * if it wants to.
     */
    if (replaced_dlg != NULL && pjsua_var.ua_cfg.cb.on_call_replace_request) {