PeerStreamer-ng

/*

 * Copyright (c) 2010-2011 Stefano Traverso

 * Copyright (c) 2010-2011 Csaba Kiraly

 * Copyright (c) 2017 Luca Baldesi

 *

 * This file is part of PeerStreamer.

 *

 * PeerStreamer is free software: you can redistribute it and/or

 * modify it under the terms of the GNU Affero General Public License as

 * published by the Free Software Foundation, either version 3 of the

 * License, or (at your option) any later version.

 *

 * PeerStreamer 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 Affero

 * General Public License for more details.

 *

 * You should have received a copy of the GNU Affero General Public License

 * along with PeerStreamer.  If not, see <http://www.gnu.org/licenses/>.

 *

 */

#include <stdint.h>

#include <stdio.h>

#include <stdbool.h>

#include <stdlib.h>

#include <sys/time.h>

#include "dbg.h"

#include "measures.h"

#include "transaction.h"

typedef struct {

        uint16_t trans_id;

        double offer_sent_time;

        double accept_received_time;

        struct nodeID *id;

        } service_time;

// List to trace peer's service times

struct service_times_element {

        service_time st;

        struct service_times_element *backward;

        struct service_times_element *forward;

        };

void _transaction_remove(struct service_times_element ** head, struct service_times_element *stl)

{

        if (stl->backward == NULL) {

                if (stl->forward)

                {

                        *head = stl->forward;

                        (*head)->backward = NULL;

                } else

                        *head = NULL;

        }

        else {

                if (stl->forward == NULL)

                        stl->backward->forward = NULL;

                else {

                        stl->backward->forward = stl->forward;

                        stl->forward->backward = stl->backward;

                }

        }

        nodeid_free(stl->st.id);

        free(stl);

}        

// Check the service times list to find elements over the timeout

void check_neighbor_status_list(struct service_times_element ** stl) {

        struct service_times_element *stl_iterator, *stl_aux;

        struct timeval current_time;

        gettimeofday(&current_time, NULL);

        dprintf("LIST: check trans_id list\n");

        // Check if list is empty

        if (*stl == NULL) {

                return;

                }

        // Start from the beginning of the list

        stl_iterator = *stl;

        stl_aux = stl_iterator->forward;

        // Iterate the list until you get the right element

        while (stl_iterator != NULL) {

                // If the element has been in the list for a period greater than the timeout, remove it

//                if ( (stl_iterator->st.accept_received_time > 0.0 && ( (current_time.tv_sec + current_time.tv_usec*1e-6) - stl_iterator->st.accept_received_time) > TRANS_ID_MAX_LIFETIME) ||  ((current_time.tv_sec + current_time.tv_usec*1e-6) - stl_iterator->st.offer_sent_time > TRANS_ID_MAX_LIFETIME ) ) {

                if ( (current_time.tv_sec + current_time.tv_usec*1e-6 - stl_iterator->st.offer_sent_time) > TRANS_ID_MAX_LIFETIME) {

                         dprintf("LIST TIMEOUT: trans_id %d, offer_sent_time %f, accept_received_time %f\n", stl_iterator->st.trans_id, (double) ((current_time.tv_sec + current_time.tv_usec*1e-6) - stl_iterator->st.offer_sent_time  ), (double) ((current_time.tv_sec + current_time.tv_usec*1e-6) - stl_iterator->st.accept_received_time));

                         //fprintf(stderr, "LIST TIMEOUT: trans_id %d, offer_sent_time %f, accept_received_time %f\n", stl_iterator->st.trans_id, (double) ((current_time.tv_sec + current_time.tv_usec*1e-6) - stl_iterator->st.offer_sent_time  ), (double) ((current_time.tv_sec + current_time.tv_usec*1e-6) - stl_iterator->st.accept_received_time));

#ifndef MONL

                        timeout_reception_measure(stl_iterator->st.id);

#endif

                _transaction_remove(stl, stl_iterator);

                        // Free the memory

                }

                stl_iterator = stl_aux;

                if (stl_iterator)

                        stl_aux = stl_aux->forward;

        }

        return;

}

// register the moment when a transaction is started

// return a  new transaction id or 0 in case of failure

uint16_t transaction_create(struct service_times_element ** stl, struct nodeID *id)

{

        struct service_times_element *stl2;

        struct timeval current_time;

        if (stl && id)

        {

                check_neighbor_status_list(stl);

                gettimeofday(&current_time, NULL);

                // create a new element in the list with its offer_sent_time and set accept_received_time to -1.0

                stl2 = (struct service_times_element*) malloc(sizeof(struct service_times_element));

                stl2->st.offer_sent_time = current_time.tv_sec + current_time.tv_usec*1e-6;

                stl2->st.accept_received_time = -1.0;

                stl2->st.id = nodeid_dup(id);

                stl2->backward = NULL;

                if (*stl)

                {

                        stl2->st.trans_id = (*stl)->st.trans_id + 1 ? (*stl)->st.trans_id + 1 : 1;

                        (*stl)->backward = stl2;

                        stl2->forward = (*stl);

                        *stl = stl2;

                } else {

                        stl2->st.trans_id = 1;

                        stl2->forward = NULL;

                        *stl = stl2;

                }

                dprintf("LIST: adding trans_id %d to the list, offer_sent_time %f -- LIST IS NOT EMPTY\n", stl2->st.trans_id, (current_time.tv_sec + current_time.tv_usec*1e-6));

                return stl2->st.trans_id;

        }

        return 0;

}

// Add the moment I received a positive select in a list

// return true if a valid trans_id is found

bool transaction_reg_accept(struct service_times_element * stl, uint16_t trans_id,const struct nodeID *id)

{

        struct service_times_element *stl_iterator;

        struct timeval current_time;

        if (stl && id && trans_id)

        {

                gettimeofday(&current_time, NULL);

                stl_iterator = stl;

                // if an accept was received, look for the trans_id and add current_time to accept_received_time field

                dprintf("LIST: changing trans_id %d to the list, accept received %f\n", trans_id, current_time.tv_sec + current_time.tv_usec*1e-6);

                // Iterate the list until you get the right element

                while (stl_iterator != NULL) {

                                if (stl_iterator->st.trans_id == trans_id) {

                                        stl_iterator->st.accept_received_time = current_time.tv_sec + current_time.tv_usec*1e-6;

        #ifndef MONL

                                        offer_accept_rtt_measure(id,stl_iterator->st.accept_received_time - stl_iterator->st.offer_sent_time);

                                        reception_measure(id);

        #endif

                                        return true;

                                        }

                                stl_iterator = stl_iterator->forward;

                }

        }

        return false;

}

// Used to get the time elapsed from the moment I get a positive select to the moment i get the ACK

// related to the same chunk

// it return -1.0 in case no trans_id is found

double transaction_remove(struct service_times_element ** stl, uint16_t trans_id) {

        struct service_times_element *stl_iterator;

        double to_return;

    dprintf("LIST: deleting trans_id %d\n", trans_id);

        // Start from the beginning of the list

        stl_iterator = *stl;

        // Iterate the list until you get the right element

        while (stl_iterator != NULL) {

                if (stl_iterator->st.trans_id == trans_id)

                        break;

                stl_iterator = stl_iterator->forward;

                }

        if (stl_iterator == NULL){

                // not found

        dprintf("LIST: deleting trans_id %d -- STL is already NULL \n", trans_id);

                return -2.0;

        }

#ifndef MONL

        // This function is called when an ACK is received, so:

        reception_measure(stl_iterator->st.id);

#endif

        to_return = stl_iterator->st.accept_received_time;

        _transaction_remove(stl, stl_iterator);

        return to_return;

}

void transaction_destroy(struct service_times_element ** head)

{

        while(*head)

        {

                _transaction_remove(head, *head);

                // in case of nodeid_dup we should free that as well

        }

}