wtp_init.c

The Kannel Open Source WAP and SMS gateway works as both an SMS gateway, for implementing keyword b

/* ==================================================================== 
 * The Kannel Software License, Version 1.0 
 * 
 * Copyright (c) 2001-2004 Kannel Group  
 * Copyright (c) 1998-2001 WapIT Ltd.   
 * All rights reserved. 
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 *    if any, must include the following acknowledgment: 
 *       "This product includes software developed by the 
 *        Kannel Group (http://www.kannel.org/)." 
 *    Alternately, this acknowledgment may appear in the software itself, 
 *    if and wherever such third-party acknowledgments normally appear. 
 * 
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 *    endorse or promote products derived from this software without 
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 * 5. Products derived from this software may not be called "Kannel", 
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 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED 
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 * ==================================================================== 
 * 
 * This software consists of voluntary contributions made by many 
 * individuals on behalf of the Kannel Group.  For more information on  
 * the Kannel Group, please see <http://www.kannel.org/>. 
 * 
 * Portions of this software are based upon software originally written at  
 * WapIT Ltd., Helsinki, Finland for the Kannel project.  
 */ 

/*
 * wtp_init.c - WTP initiator implementation
 *
 * By Aarno Syv鋘en for Wapit Ltd
 */

#include "gwlib/gwlib.h"
#include "wtp_init.h"
#include "wtp_pack.h"
#include "wap.h"

/*****************************************************************************
 * Internal data structures.
 *
 * List of initiator WTP machines
 */
static List *init_machines = NULL;

/*
 * Counter for initiator WTP machine id numbers, to make sure they are unique.
 */
static Counter *init_machine_id_counter = NULL;

/*
 * When we restart an iniator, we must set tidnew flag to avoid excessive tid
 * validations (WTP 8.8.3.2). Only an iniator uses this flag.
 */
static int tidnew = 1;

/*
 * Queue of events to be handled by WTP initiator.
 */
static List *queue = NULL;

/*
 * Give the status of the wtp initiator:
 *
 *	limbo
 *		not running at all
 *	running
 *		operating normally
 *	terminating
 *		waiting for operations to terminate, returning to limbo
 */
static enum { limbo, running, terminating } initiator_run_status = limbo;

static wap_dispatch_func_t *dispatch_to_wdp;
static wap_dispatch_func_t *dispatch_to_wsp;

/*
 * This is a timer 'tick'. All timer values multiplies of this value.
 */
static long init_timer_freq = -1;

/***************************************************************************
 *
 * Prototypes for internal functions:
 */
static void main_thread(void *arg);
 
/*
 * Create and destroy an uniniatilised wtp initiator state machine
 */
static WTPInitMachine *init_machine_create(WAPAddrTuple *tuple, unsigned short
                                           tid, int tidnew);
static void init_machine_destroy(void *sm);
static void handle_init_event(WTPInitMachine *machine, WAPEvent *event);

/*
 * Checks whether wtp initiator machines data structure includes a specific 
 * machine.
 * The machine in question is identified with with source and destination
 * address and port and tid. 
 */
static WTPInitMachine *init_machine_find_or_create(WAPEvent *event);

/*
 * Creates TR-Abort.ind event.
 */
static WAPEvent *create_tr_abort_ind(WTPInitMachine *sm, long abort_reason);

/*
 * Creates TR-Invoke.cnf event 
 */
static WAPEvent *create_tr_invoke_cnf(WTPInitMachine *machine);
static int tid_wrapped(unsigned short tid);

/*
 * Create a datagram with an Abort PDU and send it to the WDP layer.
 */
static void send_abort(WTPInitMachine *machine, long type, long reason);

/*
 * Create a datagram with an Ack PDU and send it to the WDP layer.
 */
static void send_ack(WTPInitMachine *machine, long ack_type, int rid_flag);

/*
 * We use RcvTID consistently as a internal tid representation. So newly 
 * created tids are converted. SendTID = RcvTID ^ 0x8000 (WTP 10.4.3) and for 
 * an initiator, GenTID = SendTID (WTP 10.5). 
 */
static unsigned short rcv_tid(unsigned short tid);
static void start_initiator_timer_R(WTPInitMachine *machine); 
static void stop_initiator_timer(Timer *timer);

/**************************************************************************
 *
 * EXTERNAL FUNCTIONS
 */

void wtp_initiator_init(wap_dispatch_func_t *datagram_dispatch,
			wap_dispatch_func_t *session_dispatch, long timer_freq) 
{
    init_machines = list_create();
    init_machine_id_counter = counter_create();
     
    queue = list_create();
    list_add_producer(queue);

    dispatch_to_wdp = datagram_dispatch;
    dispatch_to_wsp = session_dispatch;

    timers_init();
    init_timer_freq = timer_freq;

    gw_assert(initiator_run_status == limbo);
    initiator_run_status = running;
    gwthread_create(main_thread, NULL);
}

void wtp_initiator_shutdown(void) 
{
    gw_assert(initiator_run_status == running);
    initiator_run_status = terminating;
    list_remove_producer(queue);
    gwthread_join_every(main_thread);

    debug("wap.wtp", 0, "wtp_initiator_shutdown: %ld init_machines left",
     	  list_len(init_machines));
    list_destroy(init_machines, init_machine_destroy);
    list_destroy(queue, wap_event_destroy_item);

    counter_destroy(init_machine_id_counter);
    timers_shutdown();
}

void wtp_initiator_dispatch_event(WAPEvent *event) 
{
    list_produce(queue, event);
}

/**************************************************************************
 *
 * INTERNAL FUNCTIONS:
 */

static void main_thread(void *arg) 
{
    WTPInitMachine *sm;
    WAPEvent *e;

    while (initiator_run_status == running && 
          (e = list_consume(queue)) != NULL) {
        sm = init_machine_find_or_create(e);
	if (sm == NULL)
	    wap_event_destroy(e);
	else
	    handle_init_event(sm, e);
    }
}

static WTPInitMachine *init_machine_create(WAPAddrTuple *tuple, unsigned short
                                           tid, int tidnew)
{
     WTPInitMachine *init_machine;
	
     init_machine = gw_malloc(sizeof(WTPInitMachine)); 
        
     #define ENUM(name) init_machine->name = INITIATOR_NULL_STATE;
     #define INTEGER(name) init_machine->name = 0; 
     #define EVENT(name) init_machine->name = NULL;
     #define TIMER(name) init_machine->name = gwtimer_create(queue); 
     #define ADDRTUPLE(name) init_machine->name = NULL; 
     #define MACHINE(field) field
     #include "wtp_init_machine.def"

     list_append(init_machines, init_machine);

     init_machine->mid = counter_increase(init_machine_id_counter);
     init_machine->addr_tuple = wap_addr_tuple_duplicate(tuple);
     init_machine->tid = tid;
     init_machine->tidnew = tidnew;
	
     debug("wap.wtp", 0, "WTP: Created WTPInitMachine %p (%ld)", 
	   (void *) init_machine, init_machine->mid);

     return init_machine;
}

/*
 * Destroys a WTPInitMachine. Assumes it is safe to do so. Assumes it has 
 * already been deleted from the machines list.
 */
static void init_machine_destroy(void *p)
{
     WTPInitMachine *init_machine;

     init_machine = p;
     debug("wap.wtp", 0, "WTP: Destroying WTPInitMachine %p (%ld)", 
	    (void *) init_machine, init_machine->mid);
	
     list_delete_equal(init_machines, init_machine);
        
     #define ENUM(name) init_machine->name = INITIATOR_NULL_STATE;
     #define INTEGER(name) init_machine->name = 0; 
     #define EVENT(name) wap_event_destroy(init_machine->name); 
     #define TIMER(name) gwtimer_destroy(init_machine->name); 
     #define ADDRTUPLE(name) wap_addr_tuple_destroy(init_machine->name); 
     #define MACHINE(field) field
     #include "wtp_init_machine.def"
     gw_free(init_machine);
}

/*
 * Give the name of an initiator state in a readable form. 
 */
static unsigned char *name_init_state(int s)
{
       switch (s){
       #define INIT_STATE_NAME(state) case state: return #state;
       #define ROW(state, event, condition, action, new_state)
       #include "wtp_init_states.def"
       default:
           return "unknown state";
       }
}