X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/92c7b1c13b9caae6c737701f21276a01a75c68e1..aed6c0fceb5d7963006a105350770507030878ba:/examples/msg/app-bittorrent/tracker.c

diff --git a/examples/msg/app-bittorrent/tracker.c b/examples/msg/app-bittorrent/tracker.c
new file mode 100644
index 0000000000..72ff0d1f67
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+++ b/examples/msg/app-bittorrent/tracker.c
@@ -0,0 +1,147 @@
+/* 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;
+}