--- /dev/null
+/* Copyright (c) 2012-2015. The SimGrid Team.
+ * All rights reserved. */
+
+/* This program is free software; you can redistribute it and/or modify it
+ * under the terms of the license (GNU LGPL) which comes with this package. */
+
+#include "tracker.h"
+#include <simgrid/msg.h>
+#include <xbt/RngStream.h>
+
+static void task_free(void *data);
+
+XBT_LOG_NEW_DEFAULT_CATEGORY(msg_tracker, "Messages specific for the tracker");
+/**
+ * Tracker main function
+ * @param argc number of arguments
+ * @param argv arguments
+ */
+int tracker(int argc, char *argv[])
+{
+ int i;
+
+ RngStream stream = (RngStream) MSG_host_get_property_value(MSG_host_self(), "stream");
+ //Checking arguments
+ xbt_assert(argc == 2, "Wrong number of arguments for the tracker.");
+ //Retrieving end time
+ double deadline = xbt_str_parse_double(argv[1],"Invalid deadline: %s");
+ xbt_assert(deadline > 0, "Wrong deadline supplied");
+ //Building peers array
+ xbt_dynar_t peers_list = xbt_dynar_new(sizeof(int), NULL);
+
+ XBT_INFO("Tracker launched.");
+
+ msg_comm_t comm_received = NULL;
+ msg_task_t task_received = NULL;
+
+ while (MSG_get_clock() < deadline) {
+ if (comm_received == NULL) {
+ comm_received = MSG_task_irecv(&task_received, TRACKER_MAILBOX);
+ }
+ if (MSG_comm_test(comm_received)) {
+ //Check for correct status
+ if (MSG_comm_get_status(comm_received) == MSG_OK) {
+ //Retrieve the data sent by the peer.
+ tracker_task_data_t data = MSG_task_get_data(task_received);
+ //Add the peer to our peer list.
+ if (!is_in_list(peers_list, data->peer_id)) {
+ xbt_dynar_push_as(peers_list, int, data->peer_id);
+ }
+ //Sending peers to the peer
+ int next_peer;
+ int peers_length = xbt_dynar_length(peers_list);
+ for (i = 0; i < MAXIMUM_PAIRS && i < peers_length; i++) {
+ do {
+ next_peer =
+ xbt_dynar_get_as(peers_list,
+ RngStream_RandInt(stream, 0, peers_length - 1),
+ int);
+ } while (is_in_list(data->peers, next_peer));
+ xbt_dynar_push_as(data->peers, int, next_peer);
+ }
+ //setting the interval
+ data->interval = TRACKER_QUERY_INTERVAL;
+ //sending the task back to the peer.
+ MSG_task_dsend(task_received, data->mailbox, task_free);
+ //destroy the communication.
+ }
+ MSG_comm_destroy(comm_received);
+ comm_received = NULL;
+ task_received = NULL;
+ } else {
+ MSG_process_sleep(1);
+ }
+ }
+ //Free the remaining communication if any
+ if (comm_received) {
+ MSG_comm_destroy(comm_received);
+ }
+ //Free the peers list
+ xbt_dynar_free(&peers_list);
+
+ XBT_INFO("Tracker is leaving");
+
+ return 0;
+}
+
+/**
+ * Build a new task for the tracker.
+ * @param issuer_host_name Hostname of the issuer. For debugging purposes
+ */
+tracker_task_data_t tracker_task_data_new(const char *issuer_host_name,
+ const char *mailbox, int peer_id,
+ int uploaded, int downloaded,
+ int left)
+{
+ tracker_task_data_t task = xbt_new(s_tracker_task_data_t, 1);
+
+ task->type = TRACKER_TASK_QUERY;
+ task->issuer_host_name = issuer_host_name;
+ task->mailbox = mailbox;
+ task->peer_id = peer_id;
+ task->uploaded = uploaded;
+ task->downloaded = downloaded;
+ task->left = left;
+
+ task->peers = xbt_dynar_new(sizeof(int), NULL);
+
+ return task;
+}
+
+/**
+ * Free a tracker task that has not succefully been sent.
+ * @param data Task to free
+ */
+static void task_free(void *data)
+{
+ tracker_task_data_t task_data = MSG_task_get_data(data);
+ tracker_task_data_free(task_data);
+ MSG_task_destroy(data);
+}
+
+/**
+ * Free the data structure of a tracker task.
+ * @param task data to free
+ */
+void tracker_task_data_free(tracker_task_data_t task)
+{
+ xbt_dynar_free(&task->peers);
+ xbt_free(task);
+}
+
+/**
+ * Returns if the given id is in the peers lsit
+ * @param peers dynar containing the peers
+ * @param id identifier of the peer to test
+ */
+int is_in_list(xbt_dynar_t peers, int id)
+{
+ unsigned i;
+ int elm;
+ xbt_dynar_foreach(peers, i, elm) {
+ if (elm == id) {
+ return 1;
+ }
+ }
+ return 0;
+}
