How-To initialize libosip2.

Initialize osip.

When using osip, your first task is to initialize the parser and the state machine. This must be done prior to any use of libosip2.

#include <osip2/osip.h>
 
int i;
osip_t *osip;
i=osip_init(&osip);
if (i!=0)
  return -1;

In case you want to use the state machines (transaction management), the second step will be to set a few callbacks which will inform you of any change in the state of a SIP transaction.

Most of the following callbacks are optional. The following ones are usefull.

// callback called when a SIP message must be sent.
osip_set_cb_send_message(osip, &cb_udp_snd_message);
 
// callback called when a SIP transaction is TERMINATED.
osip_set_kill_transaction_callback(osip ,OSIP_ICT_KILL_TRANSACTION,
                         &cb_ict_kill_transaction);
osip_set_kill_transaction_callback(osip ,OSIP_IST_KILL_TRANSACTION,
                         &cb_ist_kill_transaction);
osip_set_kill_transaction_callback(osip ,OSIP_NICT_KILL_TRANSACTION,
                         &cb_nict_kill_transaction);
osip_set_kill_transaction_callback(osip ,OSIP_NIST_KILL_TRANSACTION,
                         &cb_nist_kill_transaction);
 
// callback called when the callback to send message have failed.
osip_set_transport_error_callback(osip ,OSIP_ICT_TRANSPORT_ERROR,
                            &cb_transport_error);
osip_set_transport_error_callback(osip ,OSIP_IST_TRANSPORT_ERROR,
                            &cb_transport_error);
osip_set_transport_error_callback(osip ,OSIP_NICT_TRANSPORT_ERROR,
                            &cb_transport_error);
osip_set_transport_error_callback(osip ,OSIP_NIST_TRANSPORT_ERROR,
                            &cb_transport_error);
 
// callback called when a received answer has been accepted by the transaction.
osip_set_message_callback(osip ,OSIP_ICT_STATUS_1XX_RECEIVED, &cb_rcv1xx);
osip_set_message_callback(osip ,OSIP_ICT_STATUS_2XX_RECEIVED, &cb_rcv2xx);
osip_set_message_callback(osip ,OSIP_ICT_STATUS_3XX_RECEIVED, &cb_rcv3456xx);
osip_set_message_callback(osip ,OSIP_ICT_STATUS_4XX_RECEIVED, &cb_rcv3456xx);
osip_set_message_callback(osip ,OSIP_ICT_STATUS_5XX_RECEIVED, &cb_rcv3456xx);
osip_set_message_callback(osip ,OSIP_ICT_STATUS_6XX_RECEIVED, &cb_rcv3456xx);
 
// callback called when a received answer has been accepted by the transaction.
osip_set_message_callback(osip ,OSIP_NICT_STATUS_1XX_RECEIVED, &cb_rcv1xx);
osip_set_message_callback(osip ,OSIP_NICT_STATUS_2XX_RECEIVED, &cb_rcv2xx);
osip_set_message_callback(osip ,OSIP_NICT_STATUS_3XX_RECEIVED, &cb_rcv3456xx);
osip_set_message_callback(osip ,OSIP_NICT_STATUS_4XX_RECEIVED, &cb_rcv3456xx);
osip_set_message_callback(osip ,OSIP_NICT_STATUS_5XX_RECEIVED, &cb_rcv3456xx);
osip_set_message_callback(osip ,OSIP_NICT_STATUS_6XX_RECEIVED, &cb_rcv3456xx);
    
// callback called when a received request has been accepted by the transaction.
osip_set_message_callback(osip ,OSIP_IST_INVITE_RECEIVED,     &cb_rcvreq);
osip_set_message_callback(osip ,OSIP_IST_ACK_RECEIVED,        &cb_rcvreq);
osip_set_message_callback(osip ,OSIP_NIST_REGISTER_RECEIVED,  &cb_rcvreq);
osip_set_message_callback(osip ,OSIP_NIST_BYE_RECEIVED,       &cb_rcvreq);
osip_set_message_callback(osip ,OSIP_NIST_CANCEL_RECEIVED,    &cb_rcvreq);
osip_set_message_callback(osip ,OSIP_NIST_INFO_RECEIVED,      &cb_rcvreq);
osip_set_message_callback(osip ,OSIP_NIST_OPTIONS_RECEIVED,   &cb_rcvreq);
osip_set_message_callback(osip ,OSIP_NIST_SUBSCRIBE_RECEIVED, &cb_rcvreq);
osip_set_message_callback(osip ,OSIP_NIST_NOTIFY_RECEIVED,    &cb_rcvreq);
osip_set_message_callback(osip ,OSIP_NIST_UNKNOWN_REQUEST_RECEIVED, &cb_rcvreq);
 
// other callbacks exists... They are optionnal.