1. 李思銳 voip_taiwan@yahoo.com.tw
libosip2 / libexosip
李思銳

2. 大綱
編譯libosip2
Description
Features
src directory

3. 編譯libosip2 # tar xvfz libosip2-2.2.1.tar.gz # cd libosip2-2.2.1
# ./configure
# make
# make install

4. Description The GNU oSIP library is an implementation of SIP - rfc3261

5. Features SIP parser 1. SIP header parser 2. SDP parser
SIP transaction state machines 1. ICT : Invite Client Transaction 2. NICT: Non Invite Client Transaction 3. IST : Invite Server Transaction 4. NIST: Non Invite Server Transaction

6. src directory src/osip2 SIP transaction state machines
src/osipparser2 SIP parser
src/test test programs

7. 大綱 - How-To initialize libosip2
Allocate an osip_t element
Register the callback used to send SIP message
Set a callback for transaction operation related to the end of transactions

8. Set a callback for each transaction operation related to network error

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

10. Register the callback used to send SIP message
osip_set_cb_send_message(osip, &cb_udp_snd_message);

11. Set a callback for transaction operation related to the end of transactions
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);

12. 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);

13. Set a callback for each transaction operation related to network error
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);

14. 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);

15. Set a callback for each transaction operation
osip_set_message_callback(osip, OSIP_ICT_STATUS_1XX_RECEIVED, &cb_rcv1xx);
osip_set_message_callback(osip, OSIP_ICT_STATUS_2XX_RECEIVED, &cb_rcv2xx);

16. osip_set_message_callback(osip, OSIP_ICT_STATUS_3XX_RECEIVED, &cb_rcv3456xx);

17. osip_set_message_callback(osip, OSIP_ICT_STATUS_5XX_RECEIVED, &cb_rcv3456xx);

18. osip_set_message_callback(osip, OSIP_NICT_STATUS_1XX_RECEIVED, &cb_rcv1xx);

19. osip_set_message_callback(osip, OSIP_NICT_STATUS_3XX_RECEIVED, &cb_rcv3456xx);

20. osip_set_message_callback(osip, OSIP_NICT_STATUS_5XX_RECEIVED, &cb_rcv3456xx);

21. osip_set_message_callback(osip, OSIP_IST_INVITE_RECEIVED, &cb_rcvreq);
osip_set_message_callback(osip, OSIP_IST_ACK_RECEIVED, &cb_rcvreq);

22. osip_set_message_callback(osip, OSIP_NIST_REGISTER_RECEIVED, &cb_rcvreq);
osip_set_message_callback(osip, OSIP_NIST_BYE_RECEIVED, &cb_rcvreq);

23. osip_set_message_callback(osip, OSIP_NIST_CANCEL_RECEIVED, &cb_rcvreq);
osip_set_message_callback(osip, OSIP_NIST_UNKNOWN_REQUEST_RECEIVED, &cb_rcvreq);

24. 大綱 - How-To parse URI Allocate/Free/Parse a header element
Get a string representation of a header element
Parse Via header, for example

25. Allocate/Free/Parse a header element
osip_xxx_init(osip_xxx_t **header);
osip_xxx_free(osip_xxx_t *header);
osip_xxx_parse(osip_xxx_t *header, char *buffer);

26. Get a string representation of a header element
osip_xxx_to_str(osip_xxx_t *header, char **dest);

27. Parse Via header, for example
osip_via_t *via;
char *a_via;
char *dest;
osip_via_init(&via);
osip_via_parse(via, a_via);
osip_via_to_str(via, &dest);
osip_via_free(via);

28. 大綱 - How-To parse SIP message
Parse a given buffer containing a sip request or response
Convert the message into a printable string

29. Parse a given buffer containing a sip request or response
osip_message_t *sip;
osip_message_init(&sip);
osip_message_parse(sip, msg, strlen(msg);
osip_message_free(sip);

30. Convert the message into a printable string
char *dest;
size_t length;
osip_message_to_str(sip, &result, &length);
osip_free(dest);

31. 大綱 - How-To use the sdp negotiator
How-to initialize the SDP negotiator
How-to add support for medias

32. How-to initialize the SDP negotiator
struct osip_rfc3264 *cnf;
osip_rfc3264_init(&cnf);

33. How-to add support for medias
sdp_media_t *med;
sdp_attribute_t *attr;
sdp_media_init(&med);
med->m_proto = strdup("RTP/AVP");
osip_list_add(med->m_payloads, tmp, -1);

34. sdp_attribute_init(&attr);
attr->a_att_field = strdup("rtpmap");
attr->a_att_value = strdup("0 PCMU/8000");
osip_list_add(med->a_attributes, attr, -1);
osip_rfc3264_add_audio_media(cnf, med, -1);

35. 大綱
編譯libexosip
Configure option
Description
Features

36. 編譯libexosip # tar xvfz libeXosip-0.9.0.tar.gz # cd libeXosip-0.9.0
# ./configure
# make
# make install

37. Configure option --disable-phapi --disable-miniua --disable-josua
--disable-glib

38. --disable-ms
--disable-ortp
--disable-gsm
--disable-ilbc

39. Description
eXosip is a GPL library that extend the capability of the oSIP library
It aims to implement a simple high layer API to control the SIP for sessions establishements and common extensions

40. Features
rfc3261: SIP
rfcxxxx: MESSAGE request
rfcxxxx: SIMPLE support

41. 大綱 - How-To initialize libexosip
Initiate the eXtented oSIP library
Force eXosip to use a specific local ip address in all its SIP message
Set the SIP User-Agent: header string
Release ressource used by the eXtented oSIP library

42. Initiate the eXtented oSIP library
int eXosip_init(FILE *input, FILE *output, int port);
eXosip_init(NULL, NULL, 5060);

43. Force eXosip to use a specific local ip address in all its SIP message
int eXosip_force_localip(const char *localip);
eXosip_force_localip(“ ”);

44. Set the SIP User-Agent: header string
void eXosip_set_user_agent(const char *user_agent);
eXosip_set_user_agent(“mysip”);

45. Release ressource used by the eXtented oSIP library
void eXosip_quit(void);

46. 大綱 – How to Process Event
Wait for an eXosip event
Free ressource in an eXosip event
eXosip event Management

47. Wait for an eXosip event
eXosip_event_t *eXosip_event_wait(int tv_s, int tv_ms);
eXosip_event_t *event;
event = eXosip_event_wait(0, 0);

48. Free ressource in an eXosip event
void eXosip_event_free(eXosip_event_t *je);
eXosip_event_free(event);

49. eXosip event Management
switch(event->type)
Registration Info
UAC events
UAS events
both UAS & UAC events

50. Registration Info EXOSIP_REGISTRATION_NEW EXOSIP_REGISTRATION_SUCCESS
EXOSIP_REGISTRATION_FAILURE
EXOSIP_REGISTRATION_REFRESHED
EXOSIP_REGISTRATION_TERMINATED

51. UAC events EXOSIP_CALL_NOANSWER EXOSIP_CALL_PROCEEDING
EXOSIP_CALL_RINGING
EXOSIP_CALL_ANSWERED
EXOSIP_CALL_REDIRECTED
EXOSIP_CALL_REQUESTFAILURE
EXOSIP_CALL_SERVERFAILURE
EXOSIP_CALL_GLOBALFAILURE

52. UAS events EXOSIP_CALL_NEW EXOSIP_CALL_ACK EXOSIP_CALL_CANCELLED
EXOSIP_CALL_TIMEOUT
EXOSIP_CALL_HOLD
EXOSIP_CALL_OFFHOLD
EXOSIP_CALL_CLOSED

53. both UAS & UAC events
EXOSIP_CALL_STARTAUDIO
EXOSIP_CALL_RELEASED

54. 大綱 – Sample Programs sip_reg testing Modify sip_call Compile sip_call
sip_call testing

55. sip_reg testing
# sip_reg \ -r sip:aaa.bbb.ccc.ddd \ -u \ -c \ -p U P 1000 –d

56. Modify sip_call
modify include header
change getch() to be getchar()

57. Include header #include <stdio.h> #include <stdlib.h>
#include <unistd.h>
#include <netdb.h>
#include <syslog.h>
#include <pthread.h>

58. _getch()  getchar() //if ( _kbhit() ) //switch ( _getch() )
switch ( getchar() )

59. Compile sip_call
# g++ \ -losip2 -losipparser2 -leXosip \ -o sip_call sip_call.cxx
Link error?

60. sip_call testing
eXosip_build_initial_invite( osip_message_t **invite, char *to, char *from, char *route, char *subject);

61. a - answering call
h - hangup
r - ringing
c - call
q - quit

62. 作業
整合sip_reg和sip_call兩個demo程式
修正sip_call程式的bug, 例如無法掛斷的問題等