1 /* Copyright (c) 2012-2023. The SimGrid Team.
2 * All rights reserved. */
4 /* This program is free software; you can redistribute it and/or modify it
5 * under the terms of the license (GNU LGPL) which comes with this package. */
9 #include "simgrid/actor.h"
10 #include "simgrid/comm.h"
11 #include "simgrid/engine.h"
14 XBT_LOG_NEW_DEFAULT_CATEGORY(bittorrent_tracker, "Messages specific for the tracker");
16 void tracker_answer_free(void* data)
18 tracker_answer_t a = (tracker_answer_t)data;
19 xbt_dynar_free(&a->peers);
23 static int is_in_list(const_xbt_dynar_t peers, int id)
25 return xbt_dynar_member(peers, &id);
28 void tracker_run(int argc, char* argv[])
31 xbt_assert(argc == 2, "Wrong number of arguments for the tracker.");
32 // Retrieving end time
33 double deadline = xbt_str_parse_double(argv[1], "Invalid deadline");
34 xbt_assert(deadline > 0, "Wrong deadline supplied");
36 // Building peers array
37 xbt_dynar_t peers_list = xbt_dynar_new(sizeof(int), NULL);
39 sg_mailbox_t mailbox = sg_mailbox_by_name(TRACKER_MAILBOX);
41 XBT_INFO("Tracker launched.");
42 sg_comm_t comm_received = NULL;
43 void* received = NULL;
45 while (simgrid_get_clock() < deadline) {
46 if (comm_received == NULL)
47 comm_received = sg_mailbox_get_async(mailbox, &received);
49 if (sg_comm_test(comm_received)) {
50 // Retrieve the data sent by the peer.
51 xbt_assert(received != NULL);
52 tracker_query_t tq = (tracker_query_t)received;
54 // Add the peer to our peer list.
55 if (!is_in_list(peers_list, tq->peer_id))
56 xbt_dynar_push_as(peers_list, int, tq->peer_id);
58 // Sending peers to the requesting peer
59 tracker_answer_t ta = tracker_answer_new(TRACKER_QUERY_INTERVAL);
61 int peers_length = (int)xbt_dynar_length(peers_list);
62 for (int i = 0; i < MAXIMUM_PEERS && i < peers_length; i++) {
64 next_peer = xbt_dynar_get_as(peers_list, rand() % peers_length, int);
65 } while (is_in_list(ta->peers, next_peer));
66 xbt_dynar_push_as(ta->peers, int, next_peer);
68 // sending the task back to the peer.
69 sg_comm_t answer = sg_mailbox_put_init(tq->return_mailbox, ta, TRACKER_COMM_SIZE);
70 sg_comm_detach(answer, tracker_answer_free);
76 sg_actor_sleep_for(1);
79 // Free the remaining communication if any
81 sg_comm_unref(comm_received);
82 // Free the peers list
83 xbt_dynar_free(&peers_list);
85 XBT_INFO("Tracker is leaving");
88 tracker_query_t tracker_query_new(int peer_id, sg_mailbox_t return_mailbox)
90 tracker_query_t tq = xbt_new(s_tracker_query_t, 1);
91 tq->peer_id = peer_id;
92 tq->return_mailbox = return_mailbox;
96 tracker_answer_t tracker_answer_new(int interval)
98 tracker_answer_t ta = xbt_new(s_tracker_answer_t, 1);
99 ta->interval = interval;
100 ta->peers = xbt_dynar_new(sizeof(int), NULL);