nea_server.c

sip协议栈

/*
 * This file is part of the Sofia-SIP package
 *
 * Copyright (C) 2005 Nokia Corporation.
 *
 * Contact: Pekka Pessi <[e-mail]>
 *
 * 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 nea_server.c
 * @brief Nokia Event API - event notifier implementation.
 *
 * @author Pekka Pessi <[e-mail]>
 * @author Martti Mela <[e-mail]>
 *
 * @date Created: Wed Feb 14 18:37:04 EET 2001 ppessi
 */

#include "config.h"

#include <sofia-sip/sip.h>
#include <sofia-sip/sip_header.h>
#include <sofia-sip/sip_util.h>
#include <sofia-sip/sip_status.h>
#include <sofia-sip/su_tagarg.h>

#include "nea_debug.h"

#define NONE ((void *)- 1)

#define SU_ROOT_MAGIC_T      struct nea_server_s
#define SU_MSG_ARG_T         tagi_t

#define NTA_AGENT_MAGIC_T    struct nea_server_s
#define NTA_LEG_MAGIC_T      struct nea_sub_s
#define NTA_INCOMING_MAGIC_T struct nea_sub_s
#define NTA_OUTGOING_MAGIC_T struct nea_sub_s

#include <sofia-sip/nea.h>
#include <sofia-sip/htable.h>

#include <stddef.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <stdarg.h>
#include <assert.h>
#include <limits.h>

/** Number of primary views (with different MIME type or content) */
#define NEA_VIEW_MAX (8)

/** Server object, created for every notifier.
 */
struct nea_server_s {
  su_home_t                 nes_home[1];
  su_root_t                *nes_root;
  su_timer_t               *nes_timer;
  
  nta_agent_t              *nes_agent;
  nta_leg_t                *nes_leg;

  nea_sub_t                *nes_subscribers;

  sip_require_t            *nes_require;

  sip_time_t                nes_min_expires;
  sip_time_t                nes_expires;
  sip_time_t                nes_max_expires;

  int                       nes_max_subs;
  unsigned                  nes_throttle; /**< Default throttle */
  unsigned                  nes_min_throttle; /**< Minimum throttle */
  unsigned                  nes_eventlist:1; /**< Eventlist only */
  unsigned                  nes_in_callback : 1;
  unsigned                  nes_pending_destroy : 1;
  unsigned                  nes_pending_flush : 1;
  unsigned                  nes_202_before_notify:1;

  unsigned                  nes_in_list;

  unsigned                  nes_throttled; /**< Throttled notifications? */

  char const               *nes_server;

  sip_contact_t            *nes_eventity_uri;
  sip_allow_events_t       *nes_allow_events;

  sip_allow_t              *nes_allow_methods;

  nea_new_event_f          *nes_callback;
  nea_smagic_t             *nes_context;

  /** Events.  
   * Each subscriber will be added to one of these. */ 
  nea_event_t              *nes_events;
};


/** Supported events and their subscribers  */
struct nea_event_s {
  nea_event_t              *ev_next;
  nea_event_t             **ev_prev;

  nea_watcher_f            *ev_callback;
  nea_emagic_t             *ev_magic;

  unsigned                  ev_throttle; /**< Default throttle */
  unsigned                  ev_min_throttle; /**< Minimum throttle */
  unsigned                  ev_eventlist:1; /**< Eventlist is supported */
  unsigned                  ev_reliable:1;  /**< Keep all notifications */
  unsigned                  :0;

  /** Sequence number of first unsent update */
  unsigned                  ev_throttling;
  unsigned                  ev_updated;	/**< Sequence number for updates */
  sip_require_t            *ev_require; /**< Required features */
  sip_supported_t          *ev_supported; /**< Supported features */

  sip_event_t              *ev_event;
  sip_accept_t const       *ev_default;/**< Default content type */
  sip_accept_t const       *ev_accept; /**< Supported content types */

  nea_event_view_t         *ev_views[NEA_VIEW_MAX + 1];
};

typedef struct nea_event_queue_s nea_event_queue_t;

/** Object representing particular view of event */
struct nea_event_view_s
{
  nea_event_view_t *evv_next;
  nea_event_view_t *evv_primary; 	/**< Backpointer to the primary view */

  nea_evmagic_t    *evv_magic;

  unsigned          evv_throttle; /**< Default throttle */
  unsigned          evv_min_throttle; /**< Minimum throttle */
  unsigned          evv_fake:1;		/**< This is "fake" (ie. default) view */
  unsigned          evv_private:1;	/**< This is private view */
  unsigned          evv_reliable:1;     /**< Keep all notifications */
  unsigned:0;

  /** Queued notification */
  struct nea_event_queue_s
  {
    nea_event_queue_t  *evq_next;
    unsigned            evq_updated;
    unsigned            evq_version;
    sip_content_type_t *evq_content_type;
    sip_payload_t      *evq_payload;
  } evv_head[1];
};

#define evv_version evv_head->evq_version
#define evv_updated evv_head->evq_updated
#define evv_content_type evv_head->evq_content_type
#define evv_payload evv_head->evq_payload


/** Subscription object 
 */
struct nea_sub_s {
  nea_sub_t        *s_next;
  nea_sub_t       **s_prev;
  
  nta_leg_t        *s_leg;
  nta_incoming_t   *s_irq;
  nta_outgoing_t   *s_oreq;
  
  nea_server_t     *s_nes;

  sip_contact_t    *s_local;	/**< Local contact */

  sip_from_t       *s_from;
  sip_contact_t    *s_remote;	/**< Remote contact  */
  /* sip_accept_t  *s_accept; */
  sip_event_t      *s_id;

  nea_event_t      *s_event;
  nea_event_view_t *s_view;
  nea_state_t       s_state;

  char const       *s_extended;

  sip_content_type_t *s_content_type; /** Content-Type of SUBSCRIBE body. */
  sip_payload_t    *s_payload;      /**< Body of SUBSCRIBE. */

  unsigned          s_processing : 1;
  unsigned          s_rejected : 1; 
  unsigned          s_pending_flush : 1;
  unsigned          s_garbage : 1;
  unsigned          s_fake : 1; /**< Do not send real information to user */
  unsigned          s_eventlist : 1; /**< Subscriber supported eventlist */

  sip_time_t        s_subscribed; /**< When first SUBSCRIBE was recv */
  sip_time_t        s_notified; /**< When last notification was sent */
  sip_time_t        s_expires;  /**< Expiration time. */

  unsigned          s_version;	/**< Version number set by application */

  unsigned          s_latest;	/**< External version of latest payload */
  unsigned          s_updated;	/**< Internal version of latest payload */
  unsigned          s_throttle;	/**< Minimum time between notifications */
};

/* Prototypes */

static void nea_server_pending_flush(nea_server_t *nes);

static int nea_view_update(nea_server_t *nes,
			   nea_event_t *ev,
			   nea_event_view_t **evvp,
			   int private,
			   int fake,
			   tag_type_t tag,
			   tag_value_t value,
			   ...);

static nea_sub_t *nea_sub_create(nea_server_t *nes);
static int nea_sub_is_removed(nea_sub_t const *s);
static void nea_sub_remove(nea_sub_t *s);
static void nea_sub_destroy(nea_sub_t *s);

static
int nea_server_callback(nea_sub_t *nes_as_sub,
			nta_leg_t *leg,
			nta_incoming_t *irq, 
			sip_t const *sip);

static int nea_sub_process_incoming(nea_sub_t *s,
				    nta_leg_t *leg,
				    nta_incoming_t *irq,
				    sip_t const *sip);

static int nea_sub_process_subscribe(nea_sub_t *s,
				     nta_leg_t *leg,
				     nta_incoming_t *irq,
				     sip_t const *sip);

static int nea_sub_notify(nea_server_t *nes, 
			  nea_sub_t *s, 
			  sip_time_t now, 
			  tag_type_t tag, tag_value_t value, ...);

static int response_to_notify(nea_sub_t *s,
			      nta_outgoing_t *oreq,
			      sip_t const *sip);

static void nes_event_timer(nea_server_t *nes,
			    su_timer_t *timer,
			    su_timer_arg_t *arg);

static int nea_view_queue(nea_server_t *nes, 
			  nea_event_view_t *evv, 
			  nea_event_queue_t *evq);

/** Assign an event view to subscriber. */
static inline
void nea_sub_assign_view(nea_sub_t *s, nea_event_view_t *evv)
{
  if (s->s_view != evv)
    /* Make sure we send a notification */
    s->s_updated = evv->evv_updated - 1;
  s->s_view = evv;
  s->s_throttle = evv->evv_throttle;
}

static inline 
void nea_subnode_init(nea_subnode_t *sn, nea_sub_t *s, sip_time_t now)
{
  sn->sn_state = s->s_state;
  sn->sn_fake = s->s_fake;
  sn->sn_subscriber = s;
  sn->sn_event = s->s_event;
  sn->sn_remote = s->s_from;
  sn->sn_contact = s->s_remote;
  sn->sn_content_type = s->s_content_type;
  sn->sn_payload = s->s_payload;
  if (s->s_expires != 0 && (int)(s->s_expires - now) > 0)
    sn->sn_expires = s->s_expires - now;
  else
    sn->sn_expires = 0;
  sn->sn_latest = s->s_latest;
  sn->sn_throttle = s->s_throttle;
  sn->sn_eventlist = s->s_eventlist;
  sn->sn_version = s->s_version;
  sn->sn_subscribed = now - s->s_subscribed;
  sn->sn_notified = s->s_notified;
  sn->sn_view = s->s_view;
}

/** Create an event server.
 *
 * The function nea_server_create() initializes an event server object and
 * registers it with @b nta. An event server object takes care of all events
 * for a particular URI (@em eventity).
 * 
 * @param agent       pointer to an @b nta agent object
 * @param root        pointer to an @b root object
 *燖param url         url of the server to be created
 * @param max_subs    maximum number of subscriptions
 * @param callback    authorization function, 
 *                    or @c NULL if no authorization is required
 * @param context     server context (pointer to application data)
 * @param tag, value, ... optional list of tag parameters
 *
 * @TAGS
 * The function nea_server_create() takes the following tag values as its 
 * arguments:
 * <dl>
 *
 * <dt>SIPTAG_CONTACT() or SIPTAG_CONTACT_STR()
 * <dd>The target address of the event server.
 *
 * <dt>SIPTAG_ALLOW_EVENTS()
 * <dd>The initial list of events supported by eventity. This list is
 * extended whenever a new event is created with nea_event_tcreate().
 *
 * <dt>SIPTAG_SERVER_STR()
 * <dd>The @b Server header for the event server.
 *
 * <dt>NEATAG_MINSUB()
 * <dd>Minimum duration of a subscription.
 * 
 * <dt>NEATAG_THROTTLE()
 * <dd>Default value for event throttle (by default, 5 seconds).
 * Throttle determines the minimum interval betweeen notifications. Note
 * that the notification indicating that the subscription has terminated
 * will be sent regardless of throttle.
 * 
 * The default throttle value is used if the subscriber does not include
 * a throttle parameter in @ref sip_event "Event" header of SUBSCRIBE request.
 * 
 * <dt>NEATAG_MINTHROTTLE()
 * <dd>Minimum allowed throttle value (by default, 5 seconds).
 * 
 * <dt>NEATAG_EVENTLIST()
 * <dd>If true, the subscribers must support eventlists. If SIPTAG_REQUIRE()
 * is given, it must contain the "eventlist" feature.
 *
 * <dt>NEATAG_DIALOG()
 * <dd>Give an optional NTA destination leg to event server.
 * 
 * <dt>SIPTAG_REQUIRE()/SIPTAG_REQUIRE_STR()
 * <dd>The @b Require header for the event server. The subscribers must
 * indicate support the specified features.
 *
 * </dl>
 *
 * @return
 * The function nea_server_create() returns a pointer to an event server
 * object, or @c NULL upon an error.
 */
nea_server_t *nea_server_create(nta_agent_t *agent,
				su_root_t *root,
				url_t const *url,
				int max_subs,
				nea_new_event_f *callback,
				nea_smagic_t *context,
				tag_type_t tag, tag_value_t value, ...)
{
  nea_server_t *nes = NULL;
  sip_contact_t const *contact = NULL;
  sip_allow_events_t const *allow_events = NULL;
  sip_require_t const *rq = NULL;
  char const *contact_str = NULL;
  char const *server_str = NULL;
  char const *rq_str = NULL;
  unsigned 
    min_expires = 15 * 60, 
    expires = NEA_DEFAULT_EXPIRES,
    max_expires = 24 * 60 * 60;
  nta_leg_t *leg = NONE;
  unsigned throttle = 5, min_throttle = throttle;
  int eventlist = 0;

  {
    ta_list ta;

    ta_start(ta, tag, value);

    tl_gets(ta_args(ta), 
	    SIPTAG_CONTACT_REF(contact),
	    SIPTAG_CONTACT_STR_REF(contact_str),
	    SIPTAG_ALLOW_EVENTS_REF(allow_events),
	    SIPTAG_SERVER_STR_REF(server_str),
	    SIPTAG_REQUIRE_REF(rq),
	    SIPTAG_REQUIRE_STR_REF(rq_str),
	    NEATAG_MIN_EXPIRES_REF(min_expires),
	    NEATAG_EXPIRES_REF(expires),
	    NEATAG_MAX_EXPIRES_REF(max_expires),
	    NEATAG_DIALOG_REF(leg),
	    NEATAG_THROTTLE_REF(throttle),
	    NEATAG_MINTHROTTLE_REF(min_throttle),
	    NEATAG_EVENTLIST_REF(eventlist),
	    TAG_NULL());

    ta_end(ta);
  }

  if (throttle < min_throttle)
    throttle = min_throttle;

  if (!url) {
    SU_DEBUG_5(("nea_server_create(): invalid url\n"));
    return NULL;
  }

  if (min_expires > expires || expires > max_expires) {
    SU_DEBUG_5(("nea_server_create(): invalid expiration range\n"));
    return NULL;
  }
  
  nes = su_home_new(sizeof(nea_server_t));

  if (nes) {
    su_home_t *home = nes->nes_home;

    nes->nes_root = root;
    nes->nes_agent = agent;

    nes->nes_max_subs = max_subs;

    nes->nes_min_expires = min_expires;
    nes->nes_expires = expires;
    nes->nes_max_expires = max_expires;

    nes->nes_throttle = throttle;
    nes->nes_min_throttle = min_throttle;

    if (allow_events)
      nes->nes_allow_events = sip_allow_events_dup(home, allow_events);
    else
      nes->nes_allow_events = sip_allow_events_make(home, "");

    nes->nes_allow_methods = sip_allow_make(home, "SUBSCRIBE");

    nes->nes_server = 
      su_sprintf(home, "%s%snea/" NEA_VERSION_STR " %s", 
		 server_str ? server_str : "",
		 server_str ? " " : "", 
		 nta_agent_version(agent));

    if (contact)
      nes->nes_eventity_uri = sip_contact_dup(home, contact);
    else if (contact_str)
      nes->nes_eventity_uri = sip_contact_make(home, contact_str);
    else
      nes->nes_eventity_uri = sip_contact_create(home, (url_string_t *)url, NULL);

    if (leg != NONE) {
      nes->nes_leg = leg;
      if (leg != NULL)
	nta_leg_bind(leg, nea_server_callback, (nea_sub_t*)nes);
    } else {
      nes->nes_leg = nta_leg_tcreate(agent, 
				     nea_server_callback, 
				     (nea_sub_t*)nes, 
				     NTATAG_NO_DIALOG(1),