h_table.c

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/*
 * $Id$
 *
 * Copyright (C) 2001-2003 FhG Fokus
 *
 * This file is part of SIP-router, a free SIP server.
 *
 * SIP-router 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
 *
 * SIP-router 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
 *
 * History
 * -------
 * 2003-03-06  200/INV to-tag list deallocation added;
 *             setting "kill_reason" moved in here -- it is moved
 *             from transaction state to a static var(jiri)
 * 2003-03-16  removed _TOTAG (jiri)
 * 2003-03-30  set_kr for requests only (jiri)
 * 2003-04-04  bug_fix: REQ_IN callback not called for local 
 *             UAC transactions (jiri)
 * 2003-09-12  timer_link->tg will be set only if EXTRA_DEBUG (andrei)
 * 2003-12-04  global callbacks replaceed with callbacks per transaction;
 *             completion callback merged into them as LOCAL_COMPETED (bogdan)
 * 2004-02-11  FIFO/CANCEL + alignments (hash=f(callid,cseq)) (uli+jiri)
 * 2004-02-13  t->is_invite and t->local replaced with flags;
 *             timer_link.payload removed (bogdan)
 * 2004-08-23  avp support added - move and remove avp list to/from
 *             transactions (bogdan)
 * 2006-08-11  dns failover support (andrei)
 * 2007-05-16  callbacks called on destroy (andrei)
 * 2007-06-06  don't allocate extra space for md5 if not used: syn_branch==1 
 *              (andrei)
 * 2007-06-06  switched tm bucket list to a simpler and faster clist (andrei)
 */

#include <stdlib.h>


#include "../../mem/shm_mem.h"
#include "../../hash_func.h"
#include "../../dprint.h"
#include "../../md5utils.h"
#include "../../ut.h"
#include "../../globals.h"
#include "../../error.h"
#include "../../char_msg_val.h"
#include "defs.h"
#include "t_reply.h"
#include "t_cancel.h"
#include "t_stats.h"
#include "h_table.h"
#include "../../fix_lumps.h" /* free_via_clen_lump */
#include "timer.h"
#include "uac.h" /* free_local_ack */


static enum kill_reason kr;

/* pointer to the big table where all the transaction data
   lives */
struct s_table*  _tm_table;

struct s_table* tm_get_table(void) {
        return _tm_table;
}

void reset_kr(void) {
        kr=0;
}

void set_kr( enum kill_reason _kr )
{
        kr|=_kr;
}


enum kill_reason get_kr() {
        return kr;
}


void lock_hash(int i) 
{

        int mypid;

        mypid = my_pid();
        if (likely(atomic_get(&_tm_table->entries[i].locker_pid) != mypid)) {
                lock(&_tm_table->entries[i].mutex);
                atomic_set(&_tm_table->entries[i].locker_pid, mypid);
        } else {
                /* locked within the same process that called us*/
                _tm_table->entries[i].rec_lock_level++;
        }
}


void unlock_hash(int i) 
{
        if (likely(_tm_table->entries[i].rec_lock_level == 0)) {
                atomic_set(&_tm_table->entries[i].locker_pid, 0);
                unlock(&_tm_table->entries[i].mutex);
        } else  {
                /* recursive locked => decrease rec. lock count */
                _tm_table->entries[i].rec_lock_level--;
        }
}



#ifdef TM_HASH_STATS
unsigned int transaction_count( void )
{
        unsigned int i;
        unsigned int count;

        count=0;        
        for (i=0; i<TABLE_ENTRIES; i++) 
                count+=_tm_table->entries[i].cur_entries;
        return count;
}
#endif



void free_cell( struct cell* dead_cell )
{
        char *b;
        int i;
        struct sip_msg *rpl;
        struct totag_elem *tt, *foo;
        struct tm_callback *cbs, *cbs_tmp;

        release_cell_lock( dead_cell );
        if (unlikely(has_tran_tmcbs(dead_cell, TMCB_DESTROY)))
                run_trans_callbacks(TMCB_DESTROY, dead_cell, 0, 0, 0);

        shm_lock();
        /* UA Server */
        if ( dead_cell->uas.request )
                sip_msg_free_unsafe( dead_cell->uas.request );
        if ( dead_cell->uas.response.buffer )
                shm_free_unsafe( dead_cell->uas.response.buffer );
#ifdef CANCEL_REASON_SUPPORT
        if (unlikely(dead_cell->uas.cancel_reas))
                shm_free_unsafe(dead_cell->uas.cancel_reas);
#endif /* CANCEL_REASON_SUPPORT */

        /* callbacks */
        for( cbs=(struct tm_callback*)dead_cell->tmcb_hl.first ; cbs ; ) {
                cbs_tmp = cbs;
                cbs = cbs->next;
                if (cbs_tmp->release) {
                        /* It is safer to release the shm memory lock
                         * otherwise the release function must to be aware of
                         * the lock state (Miklos)
                         */
                        shm_unlock();
                        cbs_tmp->release(cbs_tmp->param);
                        shm_lock();
                }
                shm_free_unsafe( cbs_tmp );
        }

        /* UA Clients */
        for ( i =0 ; i<dead_cell->nr_of_outgoings;  i++ )
        {
                /* retransmission buffer */
                if ( (b=dead_cell->uac[i].request.buffer) )
                        shm_free_unsafe( b );
                b=dead_cell->uac[i].local_cancel.buffer;
                if (b!=0 && b!=BUSY_BUFFER)
                        shm_free_unsafe( b );
                rpl=dead_cell->uac[i].reply;
                if (rpl && rpl!=FAKED_REPLY && rpl->msg_flags&FL_SHM_CLONE) {
                        sip_msg_free_unsafe( rpl );
                }
#ifdef USE_DNS_FAILOVER
                if (dead_cell->uac[i].dns_h.a){
                        DBG("branch %d -> dns_h.srv (%.*s) ref=%d,"
                                                        " dns_h.a (%.*s) ref=%d\n", i,
                                        dead_cell->uac[i].dns_h.srv?
                                                                dead_cell->uac[i].dns_h.srv->name_len:0,
                                        dead_cell->uac[i].dns_h.srv?
                                                                dead_cell->uac[i].dns_h.srv->name:"",
                                        dead_cell->uac[i].dns_h.srv?
                                                                dead_cell->uac[i].dns_h.srv->refcnt.val:0,
                                        dead_cell->uac[i].dns_h.a->name_len,
                                        dead_cell->uac[i].dns_h.a->name,
                                        dead_cell->uac[i].dns_h.a->refcnt.val);
                }
                dns_srv_handle_put_shm_unsafe(&dead_cell->uac[i].dns_h);
#endif
                if (unlikely(dead_cell->uac[i].path.s)) {
                        shm_free_unsafe(dead_cell->uac[i].path.s);
                }
        }

#ifdef WITH_AS_SUPPORT
        if (dead_cell->uac[0].local_ack)
                free_local_ack_unsafe(dead_cell->uac[0].local_ack);
#endif

        /* collected to tags */
        tt=dead_cell->fwded_totags;
        while(tt) {
                foo=tt->next;
                shm_free_unsafe(tt->tag.s);
                shm_free_unsafe(tt);
                tt=foo;
        }

        /* free the avp list */
        if (dead_cell->user_avps_from)
                destroy_avp_list_unsafe( &dead_cell->user_avps_from );
        if (dead_cell->user_avps_to)
                destroy_avp_list_unsafe( &dead_cell->user_avps_to );
        if (dead_cell->uri_avps_from)
                destroy_avp_list_unsafe( &dead_cell->uri_avps_from );
        if (dead_cell->uri_avps_to)
                destroy_avp_list_unsafe( &dead_cell->uri_avps_to );
#ifdef WITH_XAVP
        if (dead_cell->xavps_list)
                xavp_destroy_list_unsafe( &dead_cell->xavps_list );
#endif

        /* the cell's body */
        shm_free_unsafe( dead_cell );

        shm_unlock();
        t_stats_freed();
}



static inline void init_synonym_id( struct cell *t )
{
        struct sip_msg *p_msg;
        int size;
        char *c;
        unsigned int myrand;

        if (!syn_branch) {
                p_msg=t->uas.request;
                if (p_msg) {
                        /* char value of a proxied transaction is
                           calculated out of header-fields forming
                           transaction key
                        */
                        char_msg_val( p_msg, t->md5 );
                } else {
                        /* char value for a UAC transaction is created
                           randomly -- UAC is an originating stateful element 
                           which cannot be refreshed, so the value can be
                           anything
                        */
                        /* HACK : not long enough */
                        myrand=rand();
                        c=t->md5;
                        size=MD5_LEN;
                        memset(c, '0', size );
                        int2reverse_hex( &c, &size, myrand );
                }
        }
}

static void inline init_branches(struct cell *t)
{
        unsigned int i;
        struct ua_client *uac;

        for(i=0;i<MAX_BRANCHES;i++)
        {
                uac=&t->uac[i];
                uac->request.my_T = t;
                uac->request.branch = i;
                init_rb_timers(&uac->request);
                uac->local_cancel=uac->request;
#ifdef USE_DNS_FAILOVER
                dns_srv_handle_init(&uac->dns_h);
#endif
        }
}


struct cell*  build_cell( struct sip_msg* p_msg )
{
        struct cell* new_cell;
        int          sip_msg_len;
        avp_list_t* old;
        struct tm_callback *cbs, *cbs_tmp;
#ifdef WITH_XAVP
        sr_xavp_t** xold;
#endif

        /* allocs a new cell */
        /* if syn_branch==0 add space for md5 (MD5_LEN -sizeof(struct cell.md5)) */
        new_cell = (struct cell*)shm_malloc( sizeof( struct cell )+
                        ((MD5_LEN-sizeof(((struct cell*)0)->md5))&((syn_branch!=0)-1)) );
        if  ( !new_cell ) {
                ser_error=E_OUT_OF_MEM;
                return NULL;
        }

        /* filling with 0 */
        memset( new_cell, 0, sizeof( struct cell ) );

        /* UAS */
        new_cell->uas.response.my_T=new_cell;
        init_rb_timers(&new_cell->uas.response);
        /* timers */
        init_cell_timers(new_cell);

        old = set_avp_list(AVP_TRACK_FROM | AVP_CLASS_URI, 
                        &new_cell->uri_avps_from );
        new_cell->uri_avps_from = *old;
        *old = 0;

        old = set_avp_list(AVP_TRACK_TO | AVP_CLASS_URI, 
                        &new_cell->uri_avps_to );
        new_cell->uri_avps_to = *old;
        *old = 0;

        old = set_avp_list(AVP_TRACK_FROM | AVP_CLASS_USER, 
                        &new_cell->user_avps_from );
        new_cell->user_avps_from = *old;
        *old = 0;

        old = set_avp_list(AVP_TRACK_TO | AVP_CLASS_USER, 
                        &new_cell->user_avps_to );
        new_cell->user_avps_to = *old;
        *old = 0;

#ifdef WITH_XAVP
        xold = xavp_set_list(&new_cell->xavps_list );
        new_cell->xavps_list = *xold;
        *xold = 0;
#endif

             /* We can just store pointer to domain avps in the transaction context,
              * because they are read-only
              */
        new_cell->domain_avps_from = get_avp_list(AVP_TRACK_FROM | 
                                                                AVP_CLASS_DOMAIN);
        new_cell->domain_avps_to = get_avp_list(AVP_TRACK_TO | AVP_CLASS_DOMAIN);

        /* enter callback, which may potentially want to parse some stuff,
         * before the request is shmem-ized */
        if (p_msg) {
                set_early_tmcb_list(p_msg, new_cell);
                if(has_reqin_tmcbs())
                        run_reqin_callbacks( new_cell, p_msg, p_msg->REQ_METHOD);
        }

        if (p_msg) {
                new_cell->uas.request = sip_msg_cloner(p_msg,&sip_msg_len);
                if (!new_cell->uas.request)
                        goto error;
                new_cell->uas.end_request=((char*)new_cell->uas.request)+sip_msg_len;
        }

        /* UAC */
        init_branches(new_cell);

        new_cell->relayed_reply_branch   = -1;
        /* new_cell->T_canceled = T_UNDEFINED; */

        init_synonym_id(new_cell);
        init_cell_lock(  new_cell );
        t_stats_created();
        return new_cell;

error:
        /* Other modules may have already registered some
         * transaction callbacks and may also allocated
         * additional memory for their parameters,
         * hence TMCB_DESTROY needs to be called. (Miklos)
         */
        if (unlikely(has_tran_tmcbs(new_cell, TMCB_DESTROY)))
                run_trans_callbacks(TMCB_DESTROY, new_cell, 0, 0, 0);

        /* free the callback list */
        for( cbs=(struct tm_callback*)new_cell->tmcb_hl.first ; cbs ; ) {
                cbs_tmp = cbs;
                cbs = cbs->next;
                if (cbs_tmp->release) {
                        cbs_tmp->release(cbs_tmp->param);
                }
                shm_free( cbs_tmp );
        }
        
        destroy_avp_list(&new_cell->user_avps_from);
        destroy_avp_list(&new_cell->user_avps_to);
        destroy_avp_list(&new_cell->uri_avps_from);
        destroy_avp_list(&new_cell->uri_avps_to);
#ifdef WITH_XAVP
        xavp_destroy_list(&new_cell->xavps_list);
#endif
        shm_free(new_cell);
        /* unlink transaction AVP list and link back the global AVP list (bogdan)*/
        reset_avps();
#ifdef WITH_XAVP
        xavp_reset_list();
#endif
        return NULL;
}



/* Release all the data contained by the hash table. All the aux. structures
 *  as sems, lists, etc, are also released */
void free_hash_table(  )
{
        struct cell* p_cell;
        struct cell* tmp_cell;
        int    i;

        if (_tm_table)
        {
                /* remove the data contained by each entry */
                for( i = 0 ; i<TABLE_ENTRIES; i++)
                {
                        release_entry_lock( (_tm_table->entries)+i );
                        /* delete all synonyms at hash-collision-slot i */
                        clist_foreach_safe(&_tm_table->entries[i], p_cell, tmp_cell,
                                                                        next_c){
                                free_cell(p_cell);
                        }
                }
                shm_free(_tm_table);
                _tm_table = 0;
        }
}




/*
 */
struct s_table* init_hash_table()
{
        int              i;

        /*allocs the table*/
        _tm_table= (struct s_table*)shm_malloc( sizeof( struct s_table ) );
        if ( !_tm_table) {
                LOG(L_ERR, "ERROR: init_hash_table: no shmem for TM table\n");
                goto error0;
        }

        memset( _tm_table, 0, sizeof (struct s_table ) );

        /* try first allocating all the structures needed for syncing */
        if (lock_initialize()==-1)
                goto error1;

        /* inits the entriess */
        for(  i=0 ; i<TABLE_ENTRIES; i++ )
        {
                init_entry_lock( _tm_table, (_tm_table->entries)+i );
                _tm_table->entries[i].next_label = rand();
                /* init cell list */
                clist_init(&_tm_table->entries[i], next_c, prev_c);
        }

        return  _tm_table;

error1:
        free_hash_table( );
error0:
        return 0;
}


void tm_xdata_swap(tm_cell_t *t, tm_xlinks_t *xd, int mode)
{
        static tm_xlinks_t _txdata;
        tm_xlinks_t *x;

        if(xd==NULL)
                x = &_txdata;
        else
                x = xd;

        if(mode==0) {
                if(t==NULL)
                        return;
                x->uri_avps_from = set_avp_list(AVP_TRACK_FROM | AVP_CLASS_URI, &t->uri_avps_from );
                x->uri_avps_to = set_avp_list(AVP_TRACK_TO | AVP_CLASS_URI, &t->uri_avps_to );
                x->user_avps_from = set_avp_list(AVP_TRACK_FROM | AVP_CLASS_USER, &t->user_avps_from );
                x->user_avps_to = set_avp_list(AVP_TRACK_TO | AVP_CLASS_USER, &t->user_avps_to );
                x->domain_avps_from = set_avp_list(AVP_TRACK_FROM | AVP_CLASS_DOMAIN, &t->domain_avps_from );
                x->domain_avps_to = set_avp_list(AVP_TRACK_TO | AVP_CLASS_DOMAIN, &t->domain_avps_to );
#ifdef WITH_XAVP
                x->xavps_list = xavp_set_list(&t->xavps_list);
#endif
        } else if(mode==1) {
                /* restore original avp list */
                set_avp_list( AVP_TRACK_FROM | AVP_CLASS_URI, x->uri_avps_from );
                set_avp_list( AVP_TRACK_TO | AVP_CLASS_URI, x->uri_avps_to );
                set_avp_list( AVP_TRACK_FROM | AVP_CLASS_USER, x->user_avps_from );
                set_avp_list( AVP_TRACK_TO | AVP_CLASS_USER, x->user_avps_to );
                set_avp_list( AVP_TRACK_FROM | AVP_CLASS_DOMAIN, x->domain_avps_from );
                set_avp_list( AVP_TRACK_TO | AVP_CLASS_DOMAIN, x->domain_avps_to );
#ifdef WITH_XAVP
                xavp_set_list(x->xavps_list);
#endif
        }

}

void tm_xdata_replace(tm_xdata_t *newxd, tm_xlinks_t *bakxd)
{
        if(newxd==NULL && bakxd!=NULL) {
                set_avp_list(AVP_TRACK_FROM | AVP_CLASS_URI, bakxd->uri_avps_from);
                set_avp_list(AVP_TRACK_TO | AVP_CLASS_URI, bakxd->uri_avps_to);
                set_avp_list(AVP_TRACK_FROM | AVP_CLASS_USER, bakxd->user_avps_from);
                set_avp_list(AVP_TRACK_TO | AVP_CLASS_USER, bakxd->user_avps_to);
                set_avp_list(AVP_TRACK_FROM | AVP_CLASS_DOMAIN, bakxd->domain_avps_from);
                set_avp_list(AVP_TRACK_TO | AVP_CLASS_DOMAIN, bakxd->domain_avps_to);
#ifdef WITH_XAVP
                xavp_set_list(bakxd->xavps_list);
#endif
                return;
        }

        if(newxd!=NULL && bakxd!=NULL) {
                bakxd->uri_avps_from = set_avp_list(AVP_TRACK_FROM | AVP_CLASS_URI,
                                &newxd->uri_avps_from);
                bakxd->uri_avps_to = set_avp_list(AVP_TRACK_TO | AVP_CLASS_URI,
                                &newxd->uri_avps_to);
                bakxd->user_avps_from = set_avp_list(AVP_TRACK_FROM | AVP_CLASS_USER,
                                &newxd->user_avps_from);
                bakxd->user_avps_to = set_avp_list(AVP_TRACK_TO | AVP_CLASS_USER,
                                &newxd->user_avps_to);
                bakxd->domain_avps_from = set_avp_list(AVP_TRACK_FROM | AVP_CLASS_DOMAIN,
                                &newxd->domain_avps_from);
                bakxd->domain_avps_to = set_avp_list(AVP_TRACK_TO | AVP_CLASS_DOMAIN,
                                &newxd->domain_avps_to);
#ifdef WITH_XAVP
                bakxd->xavps_list = xavp_set_list(&newxd->xavps_list);
#endif
                return;
        }
}