Ejemplo n.º 1
0
int 
ccnl_nfn(struct ccnl_relay_s *ccnl, // struct ccnl_buf_s *orig,
         struct ccnl_prefix_s *prefix, struct ccnl_face_s *from, 
         struct configuration_s *config, struct ccnl_interest_s *interest,
         int suite, int start_locally)
{
    int num_of_required_thunks = 0;
    int thunk_request = 0;
    struct ccnl_buf_s *res = NULL;
    char str[CCNL_MAX_PACKET_SIZE];
    int i, len = 0;

    DEBUGMSG(TRACE, "ccnl_nfn(%p, %s, %p, config=%p)\n",
             (void*)ccnl, ccnl_prefix_to_path(prefix),
             (void*)from, (void*)config);

    //    prefix = ccnl_prefix_dup(prefix);
    DEBUGMSG(DEBUG, "Namecomps: %s \n", ccnl_prefix_to_path(prefix));

    if (config){
        suite = config->suite;
        thunk_request = config->fox_state->thunk_request;
        goto restart; //do not do parsing thunks again
    }

    from->flags = CCNL_FACE_FLAGS_STATIC;

    if (ccnl_nfn_thunk_already_computing(ccnl, prefix)) {
        DEBUGMSG(DEBUG, "Computation for this interest is already running\n");
        return -1;
    }
    if (ccnl_nfnprefix_isTHUNK(prefix))
        thunk_request = 1;


    // Checks first if the interest has a routing hint and then searches for it locally.
    // If it exisits, the computation is started locally,  otherwise it is directly forwarded without entering the AM.
    // Without this mechanism, there will be situations where several nodes "overtake" a computation
    // applying the same strategy and, potentially, all executing it locally (after trying all arguments).
    // TODO: this is not an elegant solution and should be improved on, because the clients cannot send a
    // computation with a routing hint on which the network applies a strategy if the routable name
    // does not exist (because each node will just forward it without ever taking it into an abstract machine).
    // encoding the routing hint more explicitely as well as additonal information (e.g. already tried names) 
    // could solve the problem. More generally speaking, additional state describing the exact situation will be required.
    
    if (interest && interest->prefix->compcnt > 1) { // forward interests with outsourced components
        struct ccnl_prefix_s *copy = ccnl_prefix_dup(prefix);
        copy->compcnt -= (1 + thunk_request);
        DEBUGMSG(DEBUG, "   checking local available of %s\n", ccnl_prefix_to_path(copy));
        ccnl_nfnprefix_clear(copy, CCNL_PREFIX_NFN | CCNL_PREFIX_THUNK); 
        if (!ccnl_nfn_local_content_search(ccnl, NULL, copy)) {
            free_prefix(copy);
            ccnl_interest_propagate(ccnl, interest);
            return 0;
        }
        free_prefix(copy);
        start_locally = 1;
    }
   
    //put packet together
#ifdef USE_SUITE_CCNTLV
    if (prefix->suite == CCNL_SUITE_CCNTLV) {
        len = prefix->complen[prefix->compcnt-1] - 4;
        memcpy(str, prefix->comp[prefix->compcnt-1] + 4, len);
        str[len] = '\0';
    } else
#endif
    {
        len = prefix->complen[prefix->compcnt-1];
        memcpy(str, prefix->comp[prefix->compcnt-1], len);
        str[len] = '\0';
    }
    if (prefix->compcnt > 1)
        len += sprintf(str + len, " ");
    for (i = 0; i < prefix->compcnt-1; i++) {
#ifdef USE_SUITE_CCNTLV
        if (prefix->suite == CCNL_SUITE_CCNTLV)
            len += sprintf(str+len,"/%.*s",prefix->complen[i]-4,prefix->comp[i]+4);
        else
#endif
            len += sprintf(str+len,"/%.*s",prefix->complen[i],prefix->comp[i]);
    }

    DEBUGMSG(DEBUG, "expr is <%s>\n", str);
    //search for result here... if found return...
    if (thunk_request)
        num_of_required_thunks = ccnl_nfn_count_required_thunks(str);
    
    ++ccnl->km->numOfRunningComputations;
restart:
    res = Krivine_reduction(ccnl, str, thunk_request, start_locally,
                            num_of_required_thunks, &config, prefix, suite);

    //stores result if computed      
    if (res) {
        struct ccnl_prefix_s *copy;
        struct ccnl_content_s *c;

        DEBUGMSG(INFO,"Computation finished: res: %.*s size: %d bytes. Running computations: %d\n",
                 res->datalen, res->data, res->datalen, ccnl->km->numOfRunningComputations);
        if (config && config->fox_state->thunk_request) {
            // ccnl_nfn_remove_thunk_from_prefix(config->prefix);
            ccnl_nfnprefix_clear(config->prefix, CCNL_PREFIX_THUNK);
        }
        copy = ccnl_prefix_dup(config->prefix);
        c = ccnl_nfn_result2content(ccnl, &copy, res->data, res->datalen);
        c->flags = CCNL_CONTENT_FLAGS_STATIC;

        set_propagate_of_interests_to_1(ccnl, c->name);
        ccnl_content_serve_pending(ccnl,c);
        ccnl_content_add2cache(ccnl, c);
        --ccnl->km->numOfRunningComputations;

        DBL_LINKED_LIST_REMOVE(ccnl->km->configuration_list, config);
        ccnl_nfn_freeConfiguration(config);
        ccnl_free(res);
    }
#ifdef USE_NACK
    else if(config->local_done){
        struct ccnl_content_s *nack;
        nack = ccnl_nfn_result2content(ccnl, &config->prefix,
                                       (unsigned char*)":NACK", 5);
        ccnl_content_serve_pending(ccnl, nack);

    }
#endif

    return 0;
}
char*
ZAM_fox(struct ccnl_relay_s *ccnl, struct configuration_s *config,
        int *restart, int *halt, char *prog, char *arg, char *contd)
{
    int local_search = 0, i;
    int parameter_number = 0;
    struct ccnl_content_s *c = NULL;
    struct ccnl_prefix_s *pref;
    struct ccnl_interest_s *interest;

    DEBUGMSG(DEBUG, "---to do: FOX <%s>\n", arg);
    ccnl_free(arg);
    if (*restart) {
        *restart = 0;
        local_search = 1;
        goto recontinue;
    }

    {
        struct stack_s *h;
        h = pop_or_resolve_from_result_stack(ccnl, config);
        assert(h);
        //TODO CHECK IF INT
        config->fox_state->num_of_params = *(int*)h->content;
        h->next = NULL;
        ccnl_nfn_freeStack(h);
    }
    DEBUGMSG(DEBUG, "NUM OF PARAMS: %d\n", config->fox_state->num_of_params);

    config->fox_state->params = ccnl_malloc(sizeof(struct ccnl_stack_s *) *
                                            config->fox_state->num_of_params);

    for (i = 0; i < config->fox_state->num_of_params; ++i) {
        //pop parameter from stack
        config->fox_state->params[i] = pop_from_stack(&config->result_stack);
        switch (config->fox_state->params[i]->type) {
        case STACK_TYPE_INT:
            DEBUGMSG(DEBUG, "  info: Parameter %d %d\n", i,
                     *(int *)config->fox_state->params[i]->content);
            break;
        case STACK_TYPE_PREFIX:
            DEBUGMSG(DEBUG, "  info: Parameter %d %s\n", i,
                     ccnl_prefix_to_path((struct ccnl_prefix_s*)
                                      config->fox_state->params[i]->content));
            break;
        default:
            break;
        }
    }
    //as long as there is a routable parameter: try to find a result
    config->fox_state->it_routable_param = 0;

    //check if last result is now available
recontinue: //loop by reentering after timeout of the interest...
    if (local_search) {
        DEBUGMSG(DEBUG, "Checking if result was received\n");
        parameter_number = choose_parameter(config);
        pref = create_namecomps(ccnl, config, parameter_number,
                        config->fox_state->params[parameter_number]->content);
        // search for a result
        c = ccnl_nfn_local_content_search(ccnl, config, pref);
        set_propagate_of_interests_to_1(ccnl, pref);
        free_prefix(pref);
        //TODO Check? //TODO remove interest here?
        if (c) {
	    DEBUGMSG(DEBUG, "Result was found\n");
            DEBUGMSG_CFWD(INFO, "data after result was found %.*s\n", c->pkt->contlen, c->pkt->content);
            goto handlecontent;
	}
    }

    //result was not delivered --> choose next parameter
    ++config->fox_state->it_routable_param;
    parameter_number = choose_parameter(config);
    if (parameter_number < 0)
        //no more parameter --> no result found, can try a local computation
        goto local_compute;
    // create new prefix with name components!!!!
    pref = create_namecomps(ccnl, config, parameter_number,
                        config->fox_state->params[parameter_number]->content);
    c = ccnl_nfn_local_content_search(ccnl, config, pref);
    if (c) {
        free_prefix(pref);
        goto handlecontent;
    }

    // Result not in cache, search over the network
//    pref2 = ccnl_prefix_dup(pref);
    interest = ccnl_nfn_query2interest(ccnl, &pref, config);
    if (pref)
        free_prefix(pref);
    if (interest) {
        ccnl_interest_propagate(ccnl, interest);
        DEBUGMSG(DEBUG, "  new interest's face is %d\n", interest->from->faceid);
    }
    // wait for content, return current program to continue later
    *halt = -1; //set halt to -1 for async computations
    return ccnl_strdup(prog);

local_compute:
    if (config->local_done)
        return NULL;

    config->local_done = 1;
    pref = ccnl_nfnprefix_mkComputePrefix(config, config->suite);
    DEBUGMSG(DEBUG, "Prefix local computation: %s\n",
             ccnl_prefix_to_path(pref));
    interest = ccnl_nfn_query2interest(ccnl, &pref, config);
    if (pref)
        free_prefix(pref);
    if (interest)
        ccnl_interest_propagate(ccnl, interest);

handlecontent: //if result was found ---> handle it
    if (c) {
#ifdef USE_NACK
        if (!strncmp((char*)c->pkt->content, ":NACK", 5)) {
            DEBUGMSG(DEBUG, "NACK RECEIVED, going to next parameter\n");
            ++config->fox_state->it_routable_param;
            return prog ? ccnl_strdup(prog) : NULL;
        }
#endif
        int isANumber = 1, i = 0;
	    for(i = 0; i < c->pkt->contlen; ++i){
	    	if(!isdigit(c->pkt->content[i])){
                isANumber = 0;
                break;
            }
	    }
	    
        if (isANumber){
            int *integer = ccnl_malloc(sizeof(int));
            *integer = strtol((char*)c->pkt->content, 0, 0);
            push_to_stack(&config->result_stack, integer, STACK_TYPE_INT);
        } else {
            struct prefix_mapping_s *mapping;
            struct ccnl_prefix_s *name =
                create_prefix_for_content_on_result_stack(ccnl, config);
            push_to_stack(&config->result_stack, name, STACK_TYPE_PREFIX);
            mapping = ccnl_malloc(sizeof(struct prefix_mapping_s));
            mapping->key = ccnl_prefix_dup(name); //TODO COPY
            mapping->value = ccnl_prefix_dup(c->pkt->pfx);
            DBL_LINKED_LIST_ADD(config->fox_state->prefix_mapping, mapping);
            DEBUGMSG(DEBUG, "Created a mapping %s - %s\n",
                        ccnl_prefix_to_path(mapping->key),
                        ccnl_prefix_to_path(mapping->value));
        }
    }
    
    DEBUGMSG(DEBUG, " FOX continuation: %s\n", contd);
    return ccnl_strdup(contd);
}