nua_stack.h 19.9 KB
Newer Older
Pekka Pessi's avatar
Pekka Pessi committed
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
/*
 * This file is part of the Sofia-SIP package
 *
 * Copyright (C) 2005 Nokia Corporation.
 *
 * Contact: Pekka Pessi <pekka.pessi@nokia.com>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public License
 * as published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA
 *
 */

/**@file nua_stack.h 
 * @brief  Nokia User Agent Library - internal stack interface
 *
 * @author Pekka Pessi <Pekka.Pessi@nokia.com>
 * @author Kai Vehmanen <Kai.Vehmanen@nokia.com>
 *
 * @date Created: Wed Feb 14 17:09:44 2001 ppessi
 * $Date: 2005/08/10 11:34:35 $
 */

#ifndef NUA_STACK_H
/** Defined when <nua_stack.h> has been included. */
#define NUA_STACK_H "$Id: nua_stack.h,v 1.2 2005/08/10 11:34:35 ppessi Exp $"

/* SOXXX: pthread doesn't seem to work...? */
#undef HAVE_PTHREAD_H

#if HAVE_UICC_H
#include <uicc.h>
#endif

#if HAVE_PTHREAD_H
#include <pthread.h>
#endif

#if HAVE_SIGCOMP
#include <sigcomp.h>
#endif

typedef struct event_s event_t;

struct event_s {
  nua_handle_t *e_nh;
  int           e_event;
  short         e_always;
  short         e_status;
  char const   *e_phrase;
  msg_t        *e_msg;
  tagi_t        e_tags[1];
};

#define       NONE ((void *)-1)

enum nh_kind {
  nh_has_nothing,
  nh_has_invite,
  nh_has_subscribe,
  nh_has_notify,
  nh_has_register,
  nh_has_streaming
};

enum nh_session {
  init_session,			/**< Initial state */
  calling_session,		/**< INVITE sent */
  proceeding_session,		/**< 18X received */
  received_session,		/**< INVITE received */
  early_session,		/**< 18X sent (w/SDP) */
  ready_session,		/**< 2XX received or sent */
  terminating_session,		/**< BYE sent */
  terminated_session		/**< BYE complete */
};

typedef struct nua_chat_s nua_chat_t;
typedef struct nua_remote_s nua_remote_t;

typedef struct nua_dialog_state nua_dialog_state_t;
typedef union  nua_dialog_usage nua_dialog_usage_t;
typedef struct nua_client_request nua_client_request_t; 

typedef void nh_pending_f(nua_handle_t *nh, 
			  nua_dialog_usage_t *du,
			  sip_time_t now);

enum nua_dialog_usage_e
{
  nua_transaction_usage = 0,
  nua_session_usage,
  nua_notifier_usage,
  nua_subscriber_usage,
  nua_register_usage,
  nua_publish_usage
};

struct nua_common_usage {
  nua_dialog_usage_t *cu_next;
  unsigned     cu_kind:3;
  unsigned     cu_terminating:1;	/**< Trying to terminate */
  unsigned     cu_ready:1;	/**< Established usage */
  unsigned:0;
  /** Pending operation.
   *
   * The nh_pending() is called 
   * a) when current time sip_now() will soon exceed nh_refresh (now > 1)
   * b) when handle operation is restarted (now is 1)
   * c) when handle is destroyed (now is 0)
   */
  nh_pending_f   *cu_pending;
  sip_time_t      cu_refresh;	/**< When execute cu_pending */
};

struct nua_session_usage {
  struct nua_common_usage su_common[1];
};

struct nua_event_usage {
  struct nua_common_usage de_common[1];
  msg_t *de_msg;
  sip_event_t const *de_event;		/**< Event of usage */
  unsigned           de_substate:2;	/**< Subscription state */
  unsigned:0;
};

struct nua_register_usage {
  struct nua_common_usage ru_common[1];
  struct sigcomp_compartment *ru_compartment;
  msg_t *ru_msg;
};

struct nua_publish_usage {
  struct nua_common_usage pu_common[1];
  sip_etag_t *pu_etag;	/**< ETag */
  msg_t *pu_msg;
};


union nua_dialog_usage
{
  nua_dialog_usage_t *du_next;
  struct nua_common_usage du_common[1];
#define du_kind du_common->cu_kind
#define du_terminating du_common->cu_terminating
#define du_ready du_common->cu_ready
#define du_pending du_common->cu_pending
#define du_refresh du_common->cu_refresh

  struct nua_session_usage du_session[1];
#define du_event du_subscriber->de_event
  struct nua_event_usage du_subscriber[1];
  struct nua_event_usage du_notifier[1];
  struct nua_register_usage du_register[1];
  struct nua_publish_usage du_publisher[1];
};


struct nua_dialog_state
{
  /** Dialog usages. */
 nua_dialog_usage_t     *ds_usage;

  /* Dialog and subscription state */
  unsigned ds_route:1;		/**< We have route */
  unsigned ds_terminated:1;	/**< Being terminated */

  unsigned ds_has_session:1;	/**< We have session */
  unsigned ds_has_register:1;	/**< We have registration */
  unsigned ds_has_publish:1;	/**< We have publish */
  unsigned ds_has_events:1;	/**< We have some events */
  unsigned ds_has_subscription:1; /**< We have subscriptions */
  unsigned ds_has_notifier:1;	/**< We have notifiers */
  unsigned :0;

  sip_from_t const *ds_local;		/**< Local address */
  sip_to_t const *ds_remote;		/**< Remote address */
  nta_leg_t      *ds_leg;
  char const     *ds_remote_tag;	/**< Remote tag (if any). 
					 * Should be non-NULL 
					 * if dialog is established.
					 */

  struct nua_remote_s {
    sip_allow_t      *nr_allow;
    sip_accept_t     *nr_accept;
    sip_require_t    *nr_require;
    sip_supported_t  *nr_supported;
    sip_user_agent_t *nr_user_agent;
  } ds_remote_ua[1];
};

typedef void crequest_restart_f(nua_handle_t *, tagi_t *tags);

struct nua_client_request
{
  nua_event_t         cr_event;		/**< Request event */
  crequest_restart_f *cr_restart;
  nta_outgoing_t     *cr_orq;
  msg_t              *cr_msg;
  nua_dialog_usage_t *cr_usage;
  unsigned short      cr_retry_count;   /**< Retry count for this request */
  unsigned            cr_sent_offer:1;  /**< Sent offer in this request */
  unsigned            cr_recv_answer:1; /**< Recv answer in response */
};

typedef struct nua_session_state
{
  /** Session-related state */
  unsigned        ss_active:1;		/**< Session is currently active. */
  
  /* enum nh_session */
  unsigned        ss_state:4;		/**< Session status (enum nh_session) */
  
  unsigned        ss_alerting:1;	/**< 180 is sent/received */
  
  unsigned        ss_complete:1;	/**< Completed SDP offer-answer */

  unsigned        ss_offer_sent:1;	/**< We have offered SDP */
  unsigned        ss_answer_recv:1;	/**< We have received SDP answer */

  unsigned        ss_offer_recv:1;	/**< We have received an offer */
  unsigned        ss_answer_sent:2;	/**< We have answered (reliably, if >1) */

  unsigned        ss_ack_needed:2;	/**< Send an ACK (do O/A, if >1) */
  unsigned        ss_update_needed:2;	/**< Send an UPDATE (do O/A if > 1) */

  unsigned        ss_precondition:1;	/**< Precondition required */

  unsigned        ss_hold_remote:1;	/**< We are holding remote */
  
  unsigned        : 0;
  
  unsigned        ss_session_timer;	/**< Value of Session-Expires (delta) */
  unsigned        ss_min_se;		/**< Minimum session expires */
  enum nua_session_refresher ss_refresher; /**< none, local or remote */

  unsigned        ss_oa_rounds;		/**< Number of O/A rounds completed */
  sdp_origin_t   *ss_o_remote;
  sdp_origin_t   *ss_o_local;

  nua_dialog_usage_t *ss_usage;

  /* Outgoing invite */
  struct nua_client_request ss_crequest[1];

  /* Incoming invite */

  /** Respond to an incoming INVITE transaction.
   *
   * When the application responds to an incoming INVITE transaction with
   * nua_respond(), the ss_respond_to_invite() is called (if non-NULL).
   */
  void (*ss_respond_to_invite)(nua_t *nua, nua_handle_t *nh,
			       int status, char const *phrase, 
			       tagi_t const *tags);
  nta_incoming_t *ss_invite_irq;

} nua_session_state_t;


typedef struct srtp_object_s
{
  int srtp_enable,
      srtp_confidentiality,
      srtp_integrity_protection;

} srtp_object_t;

#if !HAVE_MSS
typedef void ms_t;
typedef void mss_t;

/* XXX: Media subsystem parameters */

/* --cut-- for media subsystem parameters */
#define MS_SETUP_CLONE  "clone"
/** Sets the RTCP email parameter */ 
#define MS_SETUP_EMAIL  "email"
/** Provides the local SIP URI */
#define MS_LOCAL_URI  "local-uri"
/** Provides the remote SIP URI */
#define MS_REMOTE_URI  "remote-uri"
/** Provides the local SIP contact. */
#define MS_LOCAL_CONTACT  "local-contact"
/** Provides the remote SIP contact URI. */
#define MS_REMOTE_CONTACT  "remote-contact"
/** Sets the connection type */
#define MS_CONN_LIST       "connection-list"
#define MS_CONN_IN         "connection"
#define MS_CONN_IN_IP4     "connection=ip4"
#define MS_CONN_IN_IP6     "connection=ip6"
#define MS_CONN_IN_IP4_IP6 "connection=ip4+ip6"
#define MS_CONN_IN_IP6_IP4 "connection=ip6+ip4"
/** Hold mode */
#define MS_HOLD_NONE    "sendrecv"
#define MS_HOLD_REMOTE  "sendonly"
#define MS_HOLD_LOCAL   "recvonly"
#define MS_HOLD_BOTH    "inactive"
/* Offer-answer stage */
#define MS_OFFER        "offer"
#define MS_ANSWER       "answer"
/* Audio device */
#define MS_AUDIO_DEVICE   "audio-device"
/** Specifies window for local video. */
#define MS_VIDEO_LOCAL_WINDOW  "video-lw"
/** Specifies window for remote video. */
#define MS_VIDEO_REMOTE_WINDOW "video-rw"
/** Video device. */
#define MS_VIDEO_DEVICE   "video-device"
/* Specify window for local image */
#define MS_IMAGE_LOCAL_WINDOW "image-lw_image"
/** Whether to enable SRTP in RTP sessions. */
#define MS_SRTP_ENABLE "srtp-enable"
#define MS_SRTP_CONFIDENTIALITY "srtp-confidentiality"
#define MS_SRTP_INTEGRITY_PROTECTION "srtp-integrity-protection"
/* --cut-- for media subsystem parameters */
#endif

/** Media-related state */
typedef struct nua_media_state
{
  /** Media subsystem.
   *
   * Local media is enabled if nm_mss is non-null
   */

#if HAVE_MSS
  mss_t          *nm_mss;	
  ms_t           *nm_session;	/**< Media session */
#else
  void           *nm_mss;
  void           *nm_session;
#endif

  struct nua_media_a
  {
    int ma_audio:3; /**< Audio activity (send/recv) */
    int ma_video:3; /**< Video activity (send/recv) */
    int ma_image:3; /**< Image activity (send/recv) for JPIP */
    int ma_chat:3;  /**< Chat activity (send/recv) */
  } nm_active[1];

  /* These two flags help us avoid unnecessary setups */
  unsigned   nm_modified:1;    /**< Important media parameter(s) changed */
  unsigned   nm_setup_with_remote:1; /** Last setup was with remote */

  unsigned   nm_hold_remote:1; /**< We are holding remote */
  unsigned   nm_muted:1;	/**< We are muted */
  unsigned   nm_clone:1;
#if HAVE_SRTP
  unsigned   nm_srtp_enable:1;
  unsigned   nm_srtp_confidentiality:1;
  unsigned   nm_srtp_integrity_protection:1;
#endif /* HAVE_SRTP */
  unsigned:0;

  nua_chat_t     *nm_chat;	/**< Chat session */

  sdp_parser_t   *nm_sdp;  	/**< SDP from incoming request */

  int             nm_status;	/**< Status from last media operation */
  char const     *nm_phrase;	/**< Phrase from last media operation */
  char const     *nm_warning;	/**< Warnings from last media operation */

  /* Media parameters */
  char const     *nm_path;

  char const     *nm_address;
  enum nua_af     nm_af;

  char const     *nm_video_lw;
  char const     *nm_video_rw;

  char const     *nm_image_lw;
  char const     *nm_image_name; /**< JPIP target-id */
#define nm_target_image_name nm_image_name

  su_strlst_t    *nm_event_list;
} nua_media_state_t;

#define NMEDIA_ACTIVE_TAGS(nm) \
  NH_ACTIVE_MEDIA_TAGS((nm)->nm_mss != NULL, (nm)->nm_active)

#define \
  NH_ACTIVE_MEDIA_TAGS(include, ma) \
  TAG_IF((include) && (ma)->ma_audio >= 0, NUTAG_ACTIVE_AUDIO(ma->ma_audio)), \
  TAG_IF((include) && (ma)->ma_video >= 0, NUTAG_ACTIVE_VIDEO(ma->ma_video)), \
  TAG_IF((include) && (ma)->ma_image >= 0, NUTAG_ACTIVE_IMAGE(ma->ma_image)), \
  TAG_IF((include) && (ma)->ma_chat >= 0, NUTAG_ACTIVE_CHAT(ma->ma_chat))

/** NUA handle. 
 *
 */
struct nua_handle_s 
{
  su_home_t       nh_home[1];	/**< Memory home  */
  nua_handle_t   *nh_next;
  nua_handle_t  **nh_prev;

  nua_t        	 *nh_nua;	/**< Pointer to NUA object  */
  void           *nh_valid;
  nua_hmagic_t 	 *nh_magic;	/**< Application context */

  tagi_t         *nh_tags;	/**< Default tags */

#if HAVE_PTHREAD_H
  pthread_rwlock_t nh_refcount[1];  
#else
  unsigned        nh_refcount;
#endif

  /* Handle state */
  unsigned        nh_ref_by_stack:1;	/**< Has stack used the handle? */
  unsigned        nh_ref_by_user:1;	/**< Has user used the handle? */
  unsigned        nh_init:1;

  unsigned        nh_has_invite:1;     /**< Has call */
  unsigned        nh_has_subscribe:1;  /**< Has watcher */
  unsigned        nh_has_notify:1;     /**< Has notifier */
  unsigned        nh_has_register:1;   /**< Has registration */
  unsigned        nh_has_streaming:1;  /**< Has RTSP-related session */

  /* Preferences */
  unsigned        nh_auto_ack:1; /**< Automatically ACK a final response */
  unsigned        nh_early_media:1;/**< Establish early media session */
  unsigned        nh_update_refresh:1; /**< Use UPDATE to refresh */
  unsigned        nh_media_features:1;/**< Add media features */
  unsigned        nh_callee_caps:1; /**< Add callee caps */

  unsigned:0;

  sip_allow_t    *nh_allow;
  sip_supported_t *nh_supported;

  nua_event_t     nh_special;	/**< Special event */

  struct nua_client_request nh_cr[1];

  nua_dialog_state_t nh_ds[1];
  nua_session_state_t nh_ss[1];
  nua_media_state_t nh_nm[1];

  auth_client_t  *nh_auth;	/**< Authorization objects */

#if 0
  url_t const   *nh_uri;
  sip_content_type_t
                 *nh_content_type; /**< Original Content-Type */
  sip_content_disposition_t
                 *nh_disposition; /**< Original Content-Disposition */
  sip_payload_t  *nh_payload;	/**< Original request payload */
#endif

  struct nua_referral {
    nua_handle_t  *ref_handle;	 /**< Referring handle */
    sip_event_t   *ref_event;	/**< Event used with NOTIFY */
  } nh_referral[1];

  nea_server_t   *nh_notifier;	/**< SIP notifier */
};

#define NH_IS_VALID(nh) ((nh) && (nh)->nh_valid)

#define NH_STATUS(nh) \
  (nh)->nh_status, \
  (nh)->nh_phrase, \
  SIPTAG_WARNING_STR(nh->nh_warning)

#define NUA_500_ERROR 500, "Internal NUA Error"

#define SET_STATUS(_status, _phrase) status = _status, phrase = _phrase

#if HAVE_HERBIE
#include "nua_herbie.h"
#endif

struct nua_s {
  su_home_t            nua_home[1];

  /* API (client) side */
  su_root_t    	      *nua_api_root;
  su_clone_r   	       nua_clone;
  su_task_r            nua_client;
  nua_callback_f       nua_callback;
  nua_magic_t         *nua_magic;

  /**< Used by stop-and-wait args calls */
  tagi_t const        *nua_args;
  tagi_t              *nua_filter;

  /**< Local SIP address. This is never modified. */ 
  sip_from_t const   *nua_from;

  /* Protocol (server) side */
  sip_contact_t      *nua_contact;
  sip_contact_t      *nua_sips_contact;
  sip_content_type_t *nua_sdp_content;
  sip_accept_t       *nua_invite_accept; /* What we accept for invite */
  sip_supported_t    *nua_supported;
  char const         *nua_ua_name;
  sip_user_agent_t   *nua_user_agent;
  char const         *nua_organization;
  url_t        	     *nua_registrar;

  su_root_t          *nua_root;
  su_task_r           nua_server;
  nta_agent_t        *nua_nta;
  su_timer_t         *nua_timer;

#if HAVE_HERBIE
  nua_herbie_t       *nua_herbie;
#endif

#if HAVE_MSS
  mss_t              *nua_mss;	/**< Media manager */
#else
  void               *nua_mss;
#endif
  char const         *nua_media_cname;
  char const         *nua_media_descs;
  char const         *nua_media_params;
  nua_handle_t       *nua_media_handle;
  su_strlst_t        *nua_media_events;

#if HAVE_UICC_H
  uicc_t             *nua_uicc;
#endif

  /**< Default time to wait until call is completed (in seconds) */
  unsigned             nua_invite_timer;
  /** Default session timer (in seconds, 0 disables) */
# define               nua_session_timer nua_default->nh_ss->ss_session_timer
  /** Default Min-SE Delta value */
# define               nua_min_se        nua_default->nh_ss->ss_min_se

  int                  nua_retry_count;	/**< times to retry a request */

  int                  nua_max_subscriptions;

  void         	      *nua_sip_parser;

  sip_time_t           nua_shutdown;

  /* Route */
  sip_service_route_t *nua_service_route;

  /* Parameters */
  unsigned             nua_media_enable:1;
  unsigned     	       nua_autoAlert : 1;
  unsigned     	       nua_autoAnswer : 1;
  unsigned     	       nua_enableInvite : 1;
  unsigned     	       nua_enableMessage : 1;
  /** Be bug-compatible with Windows Messenger */
  unsigned     	       nua_enableMessenger : 1;
  /** PIM-IW hack */
  unsigned             nua_messageRespond : 1;

  unsigned             nua_service_route_enable:1;
  unsigned             nua_path_enable:1;

  unsigned     	       :0;

#if HAVE_SMIME		/* Start NRC Boston */
  sm_object_t          *sm;
#endif                  /* End NRC Boston */
#if HAVE_SRTP
  srtp_object_t        srtp[1];   
#endif

  nua_handle_t        *nua_handles;
  nua_handle_t       **nua_handles_tail;
};

#define nua_default    nua_handles
#define nua_allow      nua_handles->nh_allow

#define nua_media_path     nua_handles->nh_nm->nm_path
#define nua_media_af       nua_handles->nh_nm->nm_af
#define nua_media_address  nua_handles->nh_nm->nm_address

#define nua_refresher  nua_handles->nh_ss->ss_refresher

#if HAVE_FUNC
#define enter (void)SU_DEBUG_9(("nua: %s: entering\n", __func__))
#define nh_enter (void)SU_DEBUG_9(("nua %s(%p): entering\n", __func__, nh))
#elif HAVE_FUNCTION
#define enter (void)SU_DEBUG_9(("nua: %s: entering\n", __FUNCTION__))
#define nh_enter (void)SU_DEBUG_9(("nua %s(%p): entering\n", __FUNCTION__, nh))
#else
#define enter ((void)0)
#define nh_enter ((void)0)
#endif

/*# Increase reference count by one.
 *
 * Reference conting works pretty simple. Currently, application can have a
 * single reference to a handle, stack can keep multiple references. When
 * application creates a handle, it gets a reference to it. When such a
 * handle is sent to stack, stack checks the nh_ref_by_stack and makes sure
 * that it has a reference. Likewise, when stack creates a handle, and it is
 * sent to application, the application side of nua checks nh_ref_by_appl
 * and increases the reference count if needed.
 *
 * When application calls nua_handle_destroy(), it marks the handle as
 * invalid, sends a nua_r_destroy signal to stack and decreases its
 * reference count.
 * 
 */
static inline
nua_handle_t *nh_incref(nua_handle_t *nh)
{
  nh_enter;

  if (nh) {
#if HAVE_PTHREAD_H
    pthread_rwlock_rdlock(nh->nh_refcount);
#else 
    nh->nh_refcount++;		/* XXX */
#endif
  }
  return nh;
}

/*# Decrease reference count by one, return false if no more references  */
static inline
int nh_decref(nua_handle_t *nh)
{
  nh_enter;

  if (nh == NULL) 
    return 1;

#if HAVE_PTHREAD_H
  pthread_rwlock_unlock(nh->nh_refcount);
  if (pthread_rwlock_trywrlock(nh->nh_refcount) == 0) {
    SU_DEBUG_9(("nua(%p): zapped\n", nh));
    su_home_zap(nh->nh_home);
    return 0;
  }
  return 1;
#else 
  if (--nh->nh_refcount == 0) {
    SU_DEBUG_9(("nua(%p): zapped\n", nh));
    su_home_zap(nh->nh_home);
  }
  return 1;
#endif  
}


/* Internal prototypes */
int  ua_init(su_root_t *root, nua_t *nua);
void ua_deinit(su_root_t *root, nua_t *nua);
void ua_signal(nua_t *nua, su_msg_r msg, event_t *e);
int ua_event(nua_t *nua, nua_handle_t *nh, msg_t *msg,
	     nua_event_t event, int status, char const *phrase,
	     tag_type_t tag, tag_value_t value, ...);

nua_handle_t *nh_create_handle(nua_t *nua, nua_hmagic_t *hmagic,
			       tagi_t *tags);

sdp_session_t const *nmedia_parse_sdp(nua_handle_t *nh,
				    msg_payload_t const *pl,
				    msg_content_type_t const *ct,
				    struct nua_media_a *ma);
void nmedia_clear_sdp(nua_handle_t *nh);

/* Private prototypes (XXX: move to nua_priv.h; nua.c interface) */
void nua_signal(nua_t *nua, nua_handle_t *nh, msg_t *msg, int always,
		nua_event_t event, int status, char const *phrase,
		tag_type_t tag, tag_value_t value, ...);

/*  (XXX: move to nua_priv.h; nua.c interface) */
void nua_event(nua_t *root_magic, su_msg_r sumsg, event_t *e);

#define SIP_METHOD_UNKNOWN sip_method_unknown, NULL

#define UA_INTERVAL 5

#endif /* NUA_STACK_H */