1 /* Copyright (c) 2016-2023. The SimGrid Team. All rights reserved. */
3 /* This program is free software; you can redistribute it and/or modify it
4 * under the terms of the license (GNU LGPL) which comes with this package. */
8 #include "simgrid/s4u.hpp"
10 #include <xbt/random.hpp>
12 namespace sg4 = simgrid::s4u;
14 constexpr double MAX_SIMULATION_TIME = 1000;
15 constexpr double PERIODIC_STABILIZE_DELAY = 20;
16 constexpr double PERIODIC_FIX_FINGERS_DELAY = 120;
17 constexpr double PERIODIC_CHECK_PREDECESSOR_DELAY = 120;
18 constexpr double PERIODIC_LOOKUP_DELAY = 10;
19 constexpr double SLEEP_DELAY = 4.9999;
21 /* Types of tasks exchanged between nodes. */
22 enum class MessageType {
24 FIND_SUCCESSOR_ANSWER,
26 GET_PREDECESSOR_ANSWER,
31 PREDECESSOR_ALIVE_ANSWER
36 MessageType type; // type of message
37 std::string issuer_host_name = sg4::this_actor::get_host()->get_name(); // used for logging
38 int request_id = -1; // id (used by some types of messages)
39 int request_finger = 1; // finger parameter (used by some types of messages)
40 int answer_id = -1; // answer (used by some types of messages)
41 sg4::Mailbox* answer_to = nullptr; // mailbox to send an answer to (if any)
43 explicit ChordMessage(MessageType type) : type(type) {}
45 static void destroy(void* message);
49 inline static int nb_bits_;
50 inline static int nb_keys_;
51 inline static int timeout_;
54 double start_time_ = -1;
55 double deadline_ = -1;
58 int pred_id_ = -1; // predecessor id
59 simgrid::xbt::random::XbtRandom random_; // random number generator for this node
60 sg4::Mailbox* mailbox_; // my mailbox
61 std::vector<int> fingers_; // finger table,(fingers[0] is my successor)
62 int next_finger_to_fix_; // index of the next finger to fix in fix_fingers()
64 static bool is_in_interval(int id, int start, int end);
67 static void set_parameters(int nb_bits, int nb_keys, int timeout);
69 explicit Node(std::vector<std::string> args);
70 Node(const Node&) = delete;
71 Node& operator=(const Node&) = delete;
72 void join(int known_id);
77 void setFinger(int finger_index, int id);
79 void printFingerTable();
81 void setPredecessor(int predecessor_id);
82 void checkPredecessor();
83 int remoteGetPredecessor(int ask_to);
84 int closestPrecedingFinger(int id);
85 int findSuccessor(int id);
86 int remoteFindSuccessor(int ask_to, int id);
88 void notify(int predecessor_candidate_id);
89 void remoteNotify(int notify_id, int predecessor_candidate_id) const;
91 void handleMessage(ChordMessage* message);