- /* Copyright (c) 2012. The SimGrid Team.
- * All rights reserved. */
+/* Copyright (c) 2012-2016. 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 "peer.h"
#include "tracker.h"
#include "connection.h"
#include "messages.h"
-#include <msg/msg.h>
+#include <simgrid/msg.h>
#include <xbt/RngStream.h>
+#include <limits.h>
XBT_LOG_NEW_DEFAULT_CATEGORY(msg_peers, "Messages specific for the peers");
//TODO: Let users change this
/*
* File transfered data
- *
+ * For the test, default values are :
* File size: 10 pieces * 5 blocks/piece * 16384 bytes/block = 819200 bytes
*/
-static int FILE_SIZE = 10 * 5 * 16384;
-static int FILE_PIECES = 10;
-static int PIECES_BLOCKS = 5;
-static int BLOCK_SIZE = 16384;
-static int BLOCKS_REQUESTED = 2;
+#define FILE_PIECES 10
+#define PIECES_BLOCKS 5
+#define BLOCK_SIZE 16384
+#define ENABLE_END_GAME_MODE 1
-/**
- * Peer main function
- */
+/** Number of blocks asked by each request */
+#define BLOCKS_REQUESTED 2
+
+static const unsigned long int FILE_SIZE = FILE_PIECES * PIECES_BLOCKS * BLOCK_SIZE;
+
+#define SLEEP_DURATION 1
+
+/** Peer main function */
int peer(int argc, char *argv[])
{
s_peer_t peer;
xbt_assert(argc == 3 || argc == 4, "Wrong number of arguments");
//Build peer object
if (argc == 4) {
- peer_init(&peer, atoi(argv[1]), 1);
+ peer_init(&peer, xbt_str_parse_int(argv[1],"Invalid ID: %s"), 1);
} else {
- peer_init(&peer, atoi(argv[1]), 0);
+ peer_init(&peer, xbt_str_parse_int(argv[1],"Invalid ID: %s"), 0);
}
//Retrieve deadline
- double deadline = atof(argv[2]);
+ double deadline = xbt_str_parse_double(argv[2],"Invalid deadline: %s");
xbt_assert(deadline > 0, "Wrong deadline supplied");
XBT_INFO("Hi, I'm joining the network with id %d", peer.id);
//Getting peer data from the tracker.
return 0;
}
-/**
- * Peer main loop when it is leeching.
- * @param peer peer data
- * @param deadline time at which the peer has to leave
+/** @brief Peer main loop when it is leeching.
+ * @param peer peer data
+ * @param deadline time at which the peer has to leave
*/
void leech_loop(peer_t peer, double deadline)
{
* (since it couldn't have gotten more than 50 peers)
*/
send_handshake_all(peer);
- //Wait for at least one "bitfield" message.
- wait_for_pieces(peer, deadline);
XBT_DEBUG("Starting main leech loop");
+
while (MSG_get_clock() < deadline && peer->pieces < FILE_PIECES) {
if (peer->comm_received == NULL) {
peer->task_received = NULL;
handle_message(peer, peer->task_received);
}
} else {
- handle_pending_sends(peer);
- if (peer->current_piece != -1) {
- send_interested_to_peers(peer);
- } else {
- //If the current interested pieces is < MAX
- if (peer->pieces_requested < MAX_PIECES) {
- update_current_piece(peer);
- }
- }
//We don't execute the choke algorithm if we don't already have a piece
if (MSG_get_clock() >= next_choked_update && peer->pieces > 0) {
update_choked_peers(peer);
next_choked_update += UPDATE_CHOKED_INTERVAL;
} else {
- MSG_process_sleep(1);
+ MSG_process_sleep(SLEEP_DURATION);
}
}
}
+ if (peer->pieces == FILE_PIECES)
+ XBT_DEBUG("%d becomes a seeder", peer->id);
+
}
-/**
- * Peer main loop when it is seeding
- * @param peer peer data
- * @param deadline time when the peer will leave
+/** @brief Peer main loop when it is seeding
+ * @param peer peer data
+ * @param deadline time when the peer will leave
*/
void seed_loop(peer_t peer, double deadline)
{
//TODO: Change the choked peer algorithm when seeding.
next_choked_update += UPDATE_CHOKED_INTERVAL;
} else {
- MSG_process_sleep(1);
+ MSG_process_sleep(SLEEP_DURATION);
}
}
}
}
-/**
- * Retrieves the peer list from the tracker
- * @param peer current peer data
+/** @brief Retrieves the peer list from the tracker
+ * @param peer current peer data
*/
int get_peers_data(peer_t peer)
{
int success = 0, send_success = 0;
double timeout = MSG_get_clock() + GET_PEERS_TIMEOUT;
//Build the task to send to the tracker
- tracker_task_data_t data =
- tracker_task_data_new(MSG_host_get_name(MSG_host_self()),
- peer->mailbox_tracker, peer->id, 0, 0, FILE_SIZE);
+ tracker_task_data_t data = tracker_task_data_new(MSG_host_get_name(MSG_host_self()), peer->mailbox_tracker,
+ peer->id, 0, 0, FILE_SIZE);
//Build the task to send.
msg_task_t task_send = MSG_task_create(NULL, 0, TRACKER_COMM_SIZE, data);
msg_task_t task_received = NULL;
msg_comm_t comm_received;
while (!send_success && MSG_get_clock() < timeout) {
XBT_DEBUG("Sending a peer request to the tracker.");
- msg_error_t status =
- MSG_task_send_with_timeout(task_send, TRACKER_MAILBOX,
- GET_PEERS_TIMEOUT);
+ msg_error_t status = MSG_task_send_with_timeout(task_send, TRACKER_MAILBOX, GET_PEERS_TIMEOUT);
if (status == MSG_OK) {
send_success = 1;
}
//Add the peers the tracker gave us to our peer list.
xbt_dynar_foreach(data->peers, i, peer_id) {
if (peer_id != peer->id)
- xbt_dict_set_ext(peer->peers, (char *) &peer_id, sizeof(int),
- connection_new(peer_id), NULL);
+ xbt_dict_set_ext(peer->peers, (char *) &peer_id, sizeof(int), connection_new(peer_id), NULL);
}
success = 1;
//free the communication and the task
return success;
}
-/**
- * Initialize the peer data.
- * @param peer peer data
- * @param id id of the peer to take in the network
- * @param seed indicates if the peer is a seed.
+/** @brief Initialize the peer data.
+ * @param peer peer data
+ * @param id id of the peer to take in the network
+ * @param seed indicates if the peer is a seed.
*/
void peer_init(peer_t peer, int id, int seed)
{
peer->bitfield_blocks = xbt_new(char, (FILE_PIECES) * (PIECES_BLOCKS) + 1);
if (seed) {
memset(peer->bitfield, '1', sizeof(char) * (FILE_PIECES + 1));
- memset(peer->bitfield_blocks, '1',
- sizeof(char) * FILE_PIECES * (PIECES_BLOCKS));
+ memset(peer->bitfield_blocks, '1', sizeof(char) * FILE_PIECES * (PIECES_BLOCKS));
} else {
memset(peer->bitfield, '0', sizeof(char) * (FILE_PIECES + 1));
- memset(peer->bitfield_blocks, '0',
- sizeof(char) * FILE_PIECES * (PIECES_BLOCKS));
+ memset(peer->bitfield_blocks, '0', sizeof(char) * FILE_PIECES * (PIECES_BLOCKS));
}
peer->bitfield[FILE_PIECES] = '\0';
peer->pieces = 0;
peer->pieces_count = xbt_new0(short, FILE_PIECES);
- peer->pieces_requested = 0;
peer->current_pieces = xbt_dynar_new(sizeof(int), NULL);
- peer->current_piece = -1;
- peer->stream = MSG_host_get_data(MSG_host_self());
+ peer->stream = (RngStream)MSG_host_get_property_value(MSG_host_self(), "stream");
peer->comm_received = NULL;
peer->round = 0;
-
- peer->pending_sends = xbt_dynar_new(sizeof(msg_comm_t), NULL);
}
-/**
- * Destroys a poor peer object.
- */
+/** Destroys a poor peer object. */
void peer_free(peer_t peer)
{
char *key;
xbt_dict_free(&peer->peers);
xbt_dict_free(&peer->active_peers);
xbt_dynar_free(&peer->current_pieces);
- xbt_dynar_free(&peer->pending_sends);
xbt_free(peer->pieces_count);
xbt_free(peer->bitfield);
xbt_free(peer->bitfield_blocks);
}
-/**
- * Returns if a peer has finished downloading the file
- * @param bitfield peer bitfield
+/** @brief Returns if a peer has finished downloading the file
+ * @param bitfield peer bitfield
*/
int has_finished(char *bitfield)
{
return ((memchr(bitfield, '0', sizeof(char) * FILE_PIECES) == NULL) ? 1 : 0);
}
-/**
- * Handle pending sends and remove those which are done
- * @param peer Peer data
- */
-void handle_pending_sends(peer_t peer)
+int nb_interested_peers(peer_t peer)
{
- int index;
-
- while ((index = MSG_comm_testany(peer->pending_sends)) != -1) {
- msg_comm_t comm_send = xbt_dynar_get_as(peer->pending_sends, index, msg_comm_t);
- int status = MSG_comm_get_status(comm_send);
- xbt_dynar_remove_at(peer->pending_sends, index, &comm_send);
- XBT_DEBUG("Communication %p is finished with status %d, dynar size is now %lu", comm_send, status, xbt_dynar_length(peer->pending_sends));
-
- msg_task_t task = MSG_comm_get_task(comm_send);
- MSG_comm_destroy(comm_send);
+ xbt_dict_cursor_t cursor = NULL;
+ char *key;
+ connection_t connection;
+ int nb = 0;
+ xbt_dict_foreach(peer->peers, cursor, key, connection) {
+ if (connection->interested)
+ nb++;
+ }
+ return nb;
+}
- if (status != MSG_OK) {
- task_message_free(task);
+void update_active_peers_set(peer_t peer, connection_t remote_peer)
+{
+ if (remote_peer->interested && !remote_peer->choked_upload) {
+ //add in the active peers set
+ xbt_dict_set_ext(peer->active_peers, (char *) &remote_peer->id, sizeof(int), remote_peer, NULL);
+ } else {
+ //remove
+ xbt_ex_t e;
+ TRY {
+ xbt_dict_remove_ext(peer->active_peers, (char *) &remote_peer->id, sizeof(int));
+ }
+ CATCH(e) {
+ xbt_ex_free(e);
}
}
}
-/**
- * Handle a received message sent by another peer
+/** @brief Handle a received message sent by another peer
* @param peer Peer data
* @param task task received.
*/
{
message_t message = MSG_task_get_data(task);
connection_t remote_peer;
- remote_peer =
- xbt_dict_get_or_null_ext(peer->peers, (char *) &message->peer_id,
- sizeof(int));
+ remote_peer = xbt_dict_get_or_null_ext(peer->peers, (char *) &message->peer_id, sizeof(int));
switch (message->type) {
-
case MESSAGE_HANDSHAKE:
- XBT_DEBUG("Received a HANDSHAKE from %s (%s)", message->mailbox,
- message->issuer_host_name);
+ XBT_DEBUG("Received a HANDSHAKE from %s (%s)", message->mailbox, message->issuer_host_name);
//Check if the peer is in our connection list.
if (!remote_peer) {
- xbt_dict_set_ext(peer->peers, (char *) &message->peer_id, sizeof(int),
- connection_new(message->peer_id), NULL);
+ xbt_dict_set_ext(peer->peers, (char *) &message->peer_id, sizeof(int), connection_new(message->peer_id), NULL);
send_handshake(peer, message->mailbox);
}
//Send our bitfield to the peer
send_bitfield(peer, message->mailbox);
break;
case MESSAGE_BITFIELD:
- XBT_DEBUG("Recieved a BITFIELD message from %s (%s)", message->mailbox,
- message->issuer_host_name);
+ XBT_DEBUG("Recieved a BITFIELD message from %s (%s)", message->mailbox, message->issuer_host_name);
//Update the pieces list
update_pieces_count_from_bitfield(peer, message->bitfield);
//Store the bitfield
remote_peer->bitfield = xbt_strdup(message->bitfield);
- //Update the current piece
- if (peer->current_piece == -1 && peer->pieces < FILE_PIECES) {
- update_current_piece(peer);
+ xbt_assert(!remote_peer->am_interested, "Should not be interested at first");
+ if (is_interested(peer, remote_peer)) {
+ remote_peer->am_interested = 1;
+ send_interested(peer, message->mailbox);
}
break;
case MESSAGE_INTERESTED:
- XBT_DEBUG("Recieved an INTERESTED message from %s (%s)", message->mailbox,
- message->issuer_host_name);
- xbt_assert((remote_peer != NULL),
- "A non-in-our-list peer has sent us a message. WTH ?");
+ XBT_DEBUG("Recieved an INTERESTED message from %s (%s)", message->mailbox, message->issuer_host_name);
+ xbt_assert((remote_peer != NULL), "A non-in-our-list peer has sent us a message. WTH ?");
//Update the interested state of the peer.
remote_peer->interested = 1;
+ update_active_peers_set(peer, remote_peer);
break;
case MESSAGE_NOTINTERESTED:
- XBT_DEBUG("Received a NOTINTERESTED message from %s (%s)", message->mailbox,
- message->issuer_host_name);
- xbt_assert((remote_peer != NULL),
- "A non-in-our-list peer has sent us a message. WTH ?");
+ XBT_DEBUG("Received a NOTINTERESTED message from %s (%s)", message->mailbox, message->issuer_host_name);
+ xbt_assert((remote_peer != NULL), "A non-in-our-list peer has sent us a message. WTH ?");
remote_peer->interested = 0;
+ update_active_peers_set(peer, remote_peer);
break;
case MESSAGE_UNCHOKE:
- xbt_assert((remote_peer != NULL),
- "A non-in-our-list peer has sent us a message. WTH ?");
- XBT_DEBUG("Received a UNCHOKE message from %s (%s)", message->mailbox,
- message->issuer_host_name);
+ xbt_assert((remote_peer != NULL), "A non-in-our-list peer has sent us a message. WTH ?");
+ XBT_DEBUG("Received a UNCHOKE message from %s (%s)", message->mailbox, message->issuer_host_name);
+ xbt_assert(remote_peer->choked_download, "WTF !!!");
remote_peer->choked_download = 0;
- xbt_dict_set_ext(peer->active_peers, (char *) &message->peer_id,
- sizeof(int), remote_peer, NULL);
//Send requests to the peer, since it has unchoked us
- send_requests_to_peer(peer, remote_peer);
+ if (remote_peer->am_interested)
+ request_new_piece_to_peer(peer, remote_peer);
break;
case MESSAGE_CHOKE:
- xbt_assert((remote_peer != NULL),
- "A non-in-our-list peer has sent us a message. WTH ?");
- XBT_DEBUG("Received a CHOKE message from %s (%s)", message->mailbox,
- message->issuer_host_name);
+ xbt_assert((remote_peer != NULL), "A non-in-our-list peer has sent us a message. WTH ?");
+ XBT_DEBUG("Received a CHOKE message from %s (%s)", message->mailbox, message->issuer_host_name);
+ xbt_assert(!remote_peer->choked_download, "WTF !!!");
remote_peer->choked_download = 1;
- xbt_ex_t e;
- TRY {
- xbt_dict_remove_ext(peer->active_peers, (char *) &message->peer_id,
- sizeof(int));
- }
- CATCH(e) {
- xbt_ex_free(e);
- }
+ remove_current_piece(peer, remote_peer, remote_peer->current_piece);
break;
case MESSAGE_HAVE:
- XBT_DEBUG("Received a HAVE message from %s (%s) of piece %d",
- message->mailbox, message->issuer_host_name, message->index);
- xbt_assert((message->index >= 0
- && message->index < FILE_PIECES),
- "Wrong HAVE message received");
- if (remote_peer->bitfield == NULL)
- return;
+ XBT_DEBUG("Received a HAVE message from %s (%s) of piece %d", message->mailbox, message->issuer_host_name,
+ message->index);
+ xbt_assert(remote_peer->bitfield, "bitfield not received");
+ xbt_assert((message->index >= 0 && message->index < FILE_PIECES), "Wrong HAVE message received");
remote_peer->bitfield[message->index] = '1';
peer->pieces_count[message->index]++;
//If the piece is in our pieces, we tell the peer that we are interested.
- if (!remote_peer->am_interested && in_current_pieces(peer, message->index)) {
+ if (!remote_peer->am_interested && peer->bitfield[message->index] == '0') {
remote_peer->am_interested = 1;
- send_interested(peer, remote_peer->mailbox);
+ send_interested(peer, message->mailbox);
+ if (!remote_peer->choked_download)
+ request_new_piece_to_peer(peer, remote_peer);
}
break;
case MESSAGE_REQUEST:
- xbt_assert((message->index >= 0
- && message->index < FILE_PIECES), "Wrong request received");
+ xbt_assert(remote_peer->interested, "WTF !!!");
+
+ xbt_assert((message->index >= 0 && message->index < FILE_PIECES), "Wrong request received");
if (!remote_peer->choked_upload) {
- XBT_DEBUG("Received a REQUEST from %s (%s) for %d (%d,%d)",
- message->mailbox, message->issuer_host_name, message->peer_id,
- message->block_index,
- message->block_index + message->block_length);
+ XBT_DEBUG("Received a REQUEST from %s (%s) for %d (%d,%d)", message->mailbox, message->issuer_host_name,
+ message->index, message->block_index, message->block_index + message->block_length);
if (peer->bitfield[message->index] == '1') {
- send_piece(peer, message->mailbox, message->index, 0,
- message->block_index, message->block_length);
+ send_piece(peer, message->mailbox, message->index, message->block_index, message->block_length);
}
} else {
- XBT_DEBUG("Received a REQUEST from %s (%s) for %d but he is choked.",
- message->mailbox, message->issuer_host_name, message->peer_id);
+ XBT_DEBUG("Received a REQUEST from %s (%s) for %d but he is choked.", message->mailbox,
+ message->issuer_host_name, message->peer_id);
}
break;
case MESSAGE_PIECE:
- xbt_assert((message->index >= 0
- && message->index < FILE_PIECES), "Wrong piece received");
+ XBT_DEBUG("Received piece %d (%d,%d) from %s (%s)", message->index, message->block_index,
+ message->block_index + message->block_length, message->mailbox, message->issuer_host_name);
+ xbt_assert(!remote_peer->choked_download, "WTF !!!");
+ xbt_assert(remote_peer->am_interested || ENABLE_END_GAME_MODE,
+ "Can't received a piece if I'm not interested wihtout end-game mode!"
+ "piece (%d) bitfield(%s) remote bitfield(%s)", message->index, peer->bitfield, remote_peer->bitfield);
+ xbt_assert(remote_peer->choked_download != 1, "Can't received a piece if I'm choked !");
+ xbt_assert((message->index >= 0 && message->index < FILE_PIECES), "Wrong piece received");
//TODO: Execute à computation.
- if (message->stalled) {
- XBT_DEBUG("The received piece %d from %s (%s) is STALLED", message->index,
- message->mailbox, message->issuer_host_name);
- } else {
- XBT_DEBUG("Received piece %d (%d,%d) from %s (%s)", message->index,
- message->block_index,
- message->block_index + message->block_length, message->mailbox,
- message->issuer_host_name);
if (peer->bitfield[message->index] == '0') {
- update_bitfield_blocks(peer, message->index, message->block_index,
- message->block_length);
+ update_bitfield_blocks(peer, message->index, message->block_index, message->block_length);
if (piece_complete(peer, message->index)) {
- peer->pieces_requested--;
//Removing the piece from our piece list
- unsigned i;
- int piece_index = -1, piece;
- xbt_dynar_foreach(peer->current_pieces, i, piece) {
- if (piece == message->index) {
- piece_index = i;
- break;
- }
- }
- xbt_assert(piece_index != -1, "Received an incorrect piece");
- xbt_dynar_remove_at(peer->current_pieces, piece_index, NULL);
+ remove_current_piece(peer, remote_peer, message->index);
//Setting the fact that we have the piece
peer->bitfield[message->index] = '1';
peer->pieces++;
send_have(peer, message->index);
//sending UNINTERSTED to peers that doesn't have what we want.
update_interested_after_receive(peer);
+ } else { // piece not completed
+ send_request_to_peer(peer, remote_peer, message->index); // ask for the next block
}
} else {
XBT_DEBUG("However, we already have it");
+ xbt_assert(ENABLE_END_GAME_MODE, "Should not happen because we don't use end game mode !");
+ request_new_piece_to_peer(peer, remote_peer);
}
- }
break;
case MESSAGE_CANCEL:
+ XBT_DEBUG("The received CANCEL from %s (%s)", message->mailbox, message->issuer_host_name);
break;
}
//Update the peer speed.
if (remote_peer) {
- connection_add_speed_value(remote_peer,
- 1.0 / (MSG_get_clock() -
- peer->begin_receive_time));
+ connection_add_speed_value(remote_peer, 1.0 / (MSG_get_clock() - peer->begin_receive_time));
}
peer->begin_receive_time = MSG_get_clock();
task_message_free(task);
}
-/**
- * Wait for the node to receive interesting bitfield messages (ie: non empty)
- * to be received
- * @param deadline peer deadline
- * @param peer peer data
- */
-void wait_for_pieces(peer_t peer, double deadline)
+/** Selects the appropriate piece to download and requests it to the remote_peer */
+void request_new_piece_to_peer(peer_t peer, connection_t remote_peer)
{
- int finished = 0;
- while (MSG_get_clock() < deadline && !finished) {
- if (peer->comm_received == NULL) {
- peer->task_received = NULL;
- peer->comm_received = MSG_task_irecv(&peer->task_received, peer->mailbox);
- }
- msg_error_t status = MSG_comm_wait(peer->comm_received, TIMEOUT_MESSAGE);
- //free the comm already, we don't need it anymore
- MSG_comm_destroy(peer->comm_received);
- peer->comm_received = NULL;
- if (status == MSG_OK) {
- MSG_task_get_data(peer->task_received);
- handle_message(peer, peer->task_received);
- if (peer->current_piece != -1) {
- finished = 1;
- }
+ int piece = select_piece_to_download(peer, remote_peer);
+ if (piece != -1) {
+ xbt_dynar_push_as(peer->current_pieces, int, piece);
+ send_request_to_peer(peer, remote_peer, piece);
+ }
+}
+
+/** remove current_piece from the list of currently downloaded pieces. */
+void remove_current_piece(peer_t peer, connection_t remote_peer, int current_piece)
+{
+ int piece_index = -1, piece;
+ unsigned int i;
+ xbt_dynar_foreach(peer->current_pieces, i, piece) {
+ if (piece == current_piece) {
+ piece_index = i;
+ break;
}
}
+ if (piece_index != -1)
+ xbt_dynar_remove_at(peer->current_pieces, piece_index, NULL);
+ remote_peer->current_piece = -1;
}
-/**
- * Updates the list of who has a piece from a bitfield
- * @param peer peer we want to update the list
- * @param bitfield bitfield
+/** @brief Updates the list of who has a piece from a bitfield
+ * @param peer peer we want to update the list
+ * @param bitfield bitfield
*/
void update_pieces_count_from_bitfield(peer_t peer, char *bitfield)
{
}
}
-/**
- * Update the piece the peer is currently interested in.
- * There is two cases (as described in "Bittorrent Architecture Protocol", Ryan Toole :
- * If the peer has less than 3 pieces, he chooses a piece at random.
- * If the peer has more than pieces, he downloads the pieces that are the less
- * replicated
+/** @brief Return the piece to be downloaded
+ * There are two cases (as described in "Bittorrent Architecture Protocol", Ryan Toole :
+ * If a piece is partially downloaded, this piece will be selected prioritarily
+ * If the peer has strictly less than 4 pieces, he chooses a piece at random.
+ * If the peer has more than pieces, he downloads the pieces that are the less replicated (rarest policy).
+ * If all pieces have been downloaded or requested, we select a random requested piece (endgame mode).
+ * @param peer: local peer
+ * @param remote_peer: information about the connection
+ * @return the piece to download if possible. -1 otherwise
*/
-void update_current_piece(peer_t peer)
+int select_piece_to_download(peer_t peer, connection_t remote_peer)
{
- if (xbt_dynar_length(peer->current_pieces) >= (FILE_PIECES - peer->pieces)) {
- return;
+ int piece = -1;
+
+ piece = partially_downloaded_piece(peer, remote_peer);
+ // strict priority policy
+ if (piece != -1)
+ return piece;
+
+ // end game mode
+ if (xbt_dynar_length(peer->current_pieces) >= (FILE_PIECES - peer->pieces) && is_interested(peer, remote_peer)) {
+ if(!ENABLE_END_GAME_MODE)
+ return -1;
+ int i;
+ int nb_interesting_pieces = 0;
+ int random_piece_index, current_index = 0;
+ // compute the number of interesting pieces
+ for (i = 0; i < FILE_PIECES; i++) {
+ if (peer->bitfield[i] == '0' && remote_peer->bitfield[i] == '1') {
+ nb_interesting_pieces++;
+ }
+ }
+ xbt_assert(nb_interesting_pieces != 0, "WTF !!!");
+ // get a random interesting piece
+ random_piece_index = RngStream_RandInt(peer->stream, 0, nb_interesting_pieces - 1);
+ for (i = 0; i < FILE_PIECES; i++) {
+ if (peer->bitfield[i] == '0' && remote_peer->bitfield[i] == '1') {
+ if (random_piece_index == current_index) {
+ piece = i;
+ break;
+ }
+ current_index++;
+ }
+ }
+ xbt_assert(piece != -1, "WTF !!!");
+ return piece;
}
- if (1 || peer->pieces < 3) {
- int i = 0;
- do {
- peer->current_piece =
- RngStream_RandInt(peer->stream, 0, FILE_PIECES - 1);;
- i++;
- } while (!
- (peer->bitfield[peer->current_piece] == '0'
- && !in_current_pieces(peer, peer->current_piece)));
- } else {
- //Trivial min algorithm.
- int i, min_id = -1;
- short min = -1;
+ // Random first policy
+ if (peer->pieces < 4 && is_interested_and_free(peer, remote_peer)) {
+ int i;
+ int nb_interesting_pieces = 0;
+ int random_piece_index, current_index = 0;
+ // compute the number of interesting pieces
for (i = 0; i < FILE_PIECES; i++) {
- if (peer->bitfield[i] == '0') {
- min = peer->pieces_count[i];
- min_id = i;
- break;
+ if (peer->bitfield[i] == '0' && remote_peer->bitfield[i] == '1' && !in_current_pieces(peer, i)) {
+ nb_interesting_pieces++;
}
}
- xbt_assert((min > -1), "Couldn't find a minimum");
- for (i = 1; i < FILE_PIECES; i++) {
- if (peer->pieces_count[i] < min && peer->bitfield[i] == '0') {
+ xbt_assert(nb_interesting_pieces != 0, "WTF !!!");
+ // get a random interesting piece
+ random_piece_index = RngStream_RandInt(peer->stream, 0, nb_interesting_pieces - 1);
+ for (i = 0; i < FILE_PIECES; i++) {
+ if (peer->bitfield[i] == '0' && remote_peer->bitfield[i] == '1' && !in_current_pieces(peer, i)) {
+ if (random_piece_index == current_index) {
+ piece = i;
+ break;
+ }
+ current_index++;
+ }
+ }
+ xbt_assert(piece != -1, "WTF !!!");
+ return piece;
+ } else { // Rarest first policy
+ int i;
+ short min = SHRT_MAX;
+ int nb_min_pieces = 0;
+ int random_rarest_index, current_index = 0;
+ // compute the smallest number of copies of available pieces
+ for (i = 0; i < FILE_PIECES; i++) {
+ if (peer->pieces_count[i] < min && peer->bitfield[i] == '0' && remote_peer->bitfield[i] == '1'
+ && !in_current_pieces(peer, i))
min = peer->pieces_count[i];
- min_id = i;
+ }
+ xbt_assert(min != SHRT_MAX || !is_interested_and_free(peer, remote_peer), "WTF !!!");
+ // compute the number of rarest pieces
+ for (i = 0; i < FILE_PIECES; i++) {
+ if (peer->pieces_count[i] == min && peer->bitfield[i] == '0' && remote_peer->bitfield[i] == '1'
+ && !in_current_pieces(peer, i))
+ nb_min_pieces++;
+ }
+ xbt_assert(nb_min_pieces != 0 || !is_interested_and_free(peer, remote_peer), "WTF !!!");
+ // get a random rarest piece
+ random_rarest_index = RngStream_RandInt(peer->stream, 0, nb_min_pieces - 1);
+ for (i = 0; i < FILE_PIECES; i++) {
+ if (peer->pieces_count[i] == min && peer->bitfield[i] == '0' && remote_peer->bitfield[i] == '1'
+ && !in_current_pieces(peer, i)) {
+ if (random_rarest_index == current_index) {
+ piece = i;
+ break;
+ }
+ current_index++;
}
}
- peer->current_piece = min_id;
+ xbt_assert(piece != -1 || !is_interested_and_free(peer, remote_peer), "WTF !!!");
+ return piece;
}
- xbt_dynar_push_as(peer->current_pieces, int, peer->current_piece);
- XBT_DEBUG("New interested piece: %d", peer->current_piece);
- xbt_assert((peer->current_piece >= 0 && peer->current_piece < FILE_PIECES),
- "Peer want to retrieve a piece that doesn't exist.");
}
-/**
- * Update the list of current choked and unchoked peers, using the
- * choke algorithm
- * @param peer the current peer
+/** @brief Update the list of current choked and unchoked peers, using the choke algorithm
+ * @param peer the current peer
*/
void update_choked_peers(peer_t peer)
{
+ if (nb_interested_peers(peer) == 0)
+ return;
+ XBT_DEBUG("(%d) update_choked peers %d active peers", peer->id, xbt_dict_size(peer->active_peers));
//update the current round
peer->round = (peer->round + 1) % 3;
- char *key;
+ char *key, *key_choked=NULL;
connection_t peer_choosed = NULL;
+ connection_t peer_choked = NULL;
//remove a peer from the list
xbt_dict_cursor_t cursor = NULL;
xbt_dict_cursor_first(peer->active_peers, &cursor);
- if (!xbt_dict_is_empty(peer->active_peers)) {
- key = xbt_dict_cursor_get_key(cursor);
- connection_t peer_choked = xbt_dict_cursor_get_data(cursor);
- if (peer_choked) {
- send_choked(peer, peer_choked->mailbox);
- peer_choked->choked_upload = 1;
- }
- xbt_dict_remove_ext(peer->active_peers, key, sizeof(int));
+ if (xbt_dict_length(peer->active_peers) > 0) {
+ key_choked = xbt_dict_cursor_get_key(cursor);
+ peer_choked = xbt_dict_cursor_get_data(cursor);
}
xbt_dict_cursor_free(&cursor);
- /**
- * If we are currently seeding, we unchoke the peer which has
- * been unchoke the least time.
- */
+ /**If we are currently seeding, we unchoke the peer which has been unchoked the last time.*/
if (peer->pieces == FILE_PIECES) {
connection_t connection;
double unchoke_time = MSG_get_clock() + 1;
xbt_dict_foreach(peer->peers, cursor, key, connection) {
- if (connection->last_unchoke < unchoke_time && connection->interested) {
+ if (connection->last_unchoke < unchoke_time && connection->interested && connection->choked_upload) {
unchoke_time = connection->last_unchoke;
peer_choosed = connection;
}
int j = 0;
do {
//We choose a random peer to unchoke.
- int id_chosen =
- RngStream_RandInt(peer->stream, 0,
- xbt_dict_length(peer->peers) - 1);
+ int id_chosen = RngStream_RandInt(peer->stream, 0, xbt_dict_length(peer->peers) - 1);
int i = 0;
connection_t connection;
xbt_dict_foreach(peer->peers, cursor, key, connection) {
i++;
}
xbt_dict_cursor_free(&cursor);
- if (peer_choosed->interested == 0) {
+ if (!peer_choosed->interested || !peer_choosed->choked_upload) {
peer_choosed = NULL;
}
j++;
connection_t connection;
double fastest_speed = 0.0;
xbt_dict_foreach(peer->peers, cursor, key, connection) {
- if (connection->peer_speed > fastest_speed && connection->choked_upload
- && connection->interested) {
+ if (connection->peer_speed > fastest_speed && connection->choked_upload && connection->interested) {
peer_choosed = connection;
fastest_speed = connection->peer_speed;
}
}
}
-
- }
- if (peer_choosed != NULL) {
- peer_choosed->choked_upload = 0;
- xbt_dict_set_ext(peer->active_peers, (char *) &peer_choosed->id,
- sizeof(int), peer_choosed, NULL);
- peer_choosed->last_unchoke = MSG_get_clock();
- send_unchoked(peer, peer_choosed->mailbox);
}
+ if (peer_choosed != NULL)
+ XBT_DEBUG("(%d) update_choked peers unchoked (%d) ; int (%d) ; choked (%d) ",
+ peer->id, peer_choosed->id, peer_choosed->interested, peer_choosed->choked_upload);
+
+ if (peer_choked != peer_choosed) {
+ if (peer_choked != NULL) {
+ xbt_assert((!peer_choked->choked_upload), "Tries to choked a choked peer");
+ peer_choked->choked_upload = 1;
+ xbt_assert((*((int *) key_choked) == peer_choked->id), "WTF !!!");
+ update_active_peers_set(peer, peer_choked);
+ XBT_DEBUG("(%d) Sending a CHOKE to %d", peer->id, peer_choked->id);
+ send_choked(peer, peer_choked->mailbox);
+ }
+ if (peer_choosed != NULL) {
+ xbt_assert((peer_choosed->choked_upload), "Tries to unchoked an unchoked peer");
+ peer_choosed->choked_upload = 0;
+ xbt_dict_set_ext(peer->active_peers, (char *) &peer_choosed->id, sizeof(int), peer_choosed, NULL);
+ peer_choosed->last_unchoke = MSG_get_clock();
+ XBT_DEBUG("(%d) Sending a UNCHOKE to %d", peer->id, peer_choosed->id);
+ update_active_peers_set(peer, peer_choosed);
+ send_unchoked(peer, peer_choosed->mailbox);
+ }
+ }
}
-/**
- * Updates our "interested" state about peers: send "not interested" to peers
- * that don't have any more pieces we want.
- * @param peer our peer data
+/** @brief Update "interested" state of peers: send "not interested" to peers that don't have any more pieces we want.
+ * @param peer our peer data
*/
void update_interested_after_receive(peer_t peer)
{
char *key;
xbt_dict_cursor_t cursor;
connection_t connection;
- unsigned cpt;
- int interested, piece;
+ int interested;
xbt_dict_foreach(peer->peers, cursor, key, connection) {
interested = 0;
if (connection->am_interested) {
+ xbt_assert(connection->bitfield, "Bitfield not received");
//Check if the peer still has a piece we want.
- xbt_dynar_foreach(peer->current_pieces, cpt, piece) {
- xbt_assert((piece >= 0), "Wrong piece.");
- if (connection->bitfield && connection->bitfield[piece] == '1') {
+ int i;
+ for (i = 0; i < FILE_PIECES; i++) {
+ if (connection->bitfield[i] == '1' && peer->bitfield[i] == '0') {
interested = 1;
break;
}
}
- if (!interested) {
+ if (!interested) { //no more piece to download from connection
connection->am_interested = 0;
send_notinterested(peer, connection->mailbox);
}
}
}
-void update_bitfield_blocks(peer_t peer, int index, int block_index,
- int block_length)
+void update_bitfield_blocks(peer_t peer, int index, int block_index, int block_length)
{
int i;
xbt_assert((index >= 0 && index <= FILE_PIECES), "Wrong piece.");
- xbt_assert((block_index >= 0
- && block_index <= PIECES_BLOCKS), "Wrong block : %d.",
- block_index);
+ xbt_assert((block_index >= 0 && block_index <= PIECES_BLOCKS), "Wrong block : %d.", block_index);
for (i = block_index; i < (block_index + block_length); i++) {
peer->bitfield_blocks[index * PIECES_BLOCKS + i] = '1';
}
}
-/**
- * Returns if a peer has completed the download of a piece
- */
+/** Returns if a peer has completed the download of a piece */
int piece_complete(peer_t peer, int index)
{
int i;
return 1;
}
-/**
- * Returns the first block that a peer doesn't have in a piece
- */
+/** Returns the first block that a peer doesn't have in a piece. If the peer has all blocks of the piece, returns -1. */
int get_first_block(peer_t peer, int piece)
{
int i;
return -1;
}
-/**
- * Send request messages to a peer that have unchoked us
- * @param peer peer
- * @param remote_peer peer data to the peer we want to send the request
- */
-void send_requests_to_peer(peer_t peer, connection_t remote_peer)
+/** Indicates if the remote peer has a piece not stored by the local peer */
+int is_interested(peer_t peer, connection_t remote_peer)
{
- unsigned i;
- int piece, block_index, block_length;
- xbt_dynar_foreach(peer->current_pieces, i, piece) {
- if (remote_peer->bitfield && remote_peer->bitfield[piece] == '1') {
- block_index = get_first_block(peer, piece);
- if (block_index != -1) {
- block_length = PIECES_BLOCKS - block_index;
- block_length = min(BLOCKS_REQUESTED, block_length);
- send_request(peer, remote_peer->mailbox, piece, block_index,
- block_length);
- break;
- }
+ xbt_assert(remote_peer->bitfield, "Bitfield not received");
+ int i;
+ for (i = 0; i < FILE_PIECES; i++) {
+ if (remote_peer->bitfield[i] == '1' && peer->bitfield[i] == '0') {
+ return 1;
+ }
+ }
+ return 0;
+}
+
+/** Indicates if the remote peer has a piece not stored by the local peer nor requested by the local peer */
+int is_interested_and_free(peer_t peer, connection_t remote_peer)
+{
+ xbt_assert(remote_peer->bitfield, "Bitfield not received");
+ int i;
+ for (i = 0; i < FILE_PIECES; i++) {
+ if (remote_peer->bitfield[i] == '1' && peer->bitfield[i] == '0' && !in_current_pieces(peer, i)) {
+ return 1;
+ }
+ }
+ return 0;
+}
+
+/** Returns a piece that is partially downloaded and stored by the remote peer if any -1 otherwise. */
+int partially_downloaded_piece(peer_t peer, connection_t remote_peer)
+{
+ xbt_assert(remote_peer->bitfield, "Bitfield not received");
+ int i;
+ for (i = 0; i < FILE_PIECES; i++) {
+ if (remote_peer->bitfield[i] == '1' && peer->bitfield[i] == '0' && !in_current_pieces(peer, i)) {
+ if (get_first_block(peer, i) > 0)
+ return i;
}
}
+ return -1;
}
-/**
- * Find the peers that have the current interested piece and send them
- * the "interested" message
+/** @brief Send request messages to a peer that have unchoked us
+ * @param peer peer
+ * @param remote_peer peer data to the peer we want to send the request
*/
-void send_interested_to_peers(peer_t peer)
+void send_request_to_peer(peer_t peer, connection_t remote_peer, int piece)
{
- char *key;
- xbt_dict_cursor_t cursor = NULL;
- connection_t connection;
- xbt_assert((peer->current_piece != -1),
- "Tried to send a interested message wheras the current_piece is -1");
- xbt_dict_foreach(peer->peers, cursor, key, connection) {
- if (connection->bitfield
- && connection->bitfield[peer->current_piece] == '1') {
- connection->am_interested = 1;
- msg_task_t task =
- task_message_new(MESSAGE_INTERESTED, peer->hostname, peer->mailbox,
- peer->id, task_message_size(MESSAGE_INTERESTED));
- MSG_task_dsend(task, connection->mailbox, task_message_free);
- XBT_DEBUG("Send INTERESTED to %s", connection->mailbox);
+ remote_peer->current_piece = piece;
+ int block_index, block_length;
+ xbt_assert(remote_peer->bitfield, "bitfield not received");
+ xbt_assert(remote_peer->bitfield[piece] == '1', "WTF !!!");
+ block_index = get_first_block(peer, piece);
+ if (block_index != -1) {
+ block_length = PIECES_BLOCKS - block_index;
+ block_length = min(BLOCKS_REQUESTED, block_length);
+ send_request(peer, remote_peer->mailbox, piece, block_index, block_length);
+ }
+}
+
+/** Indicates if a piece is currently being downloaded by the peer. */
+int in_current_pieces(peer_t peer, int piece)
+{
+ unsigned i;
+ int peer_piece;
+ xbt_dynar_foreach(peer->current_pieces, i, peer_piece) {
+ if (peer_piece == piece) {
+ return 1;
}
}
- peer->current_piece = -1;
- peer->pieces_requested++;
+ return 0;
}
-/**
- * Send a "interested" message to a peer
- * @param peer peer data
- * @param mailbox destination mailbox
+/***********************************************************
+ *
+ * Low level message functions
+ *
+ ***********************************************************/
+
+
+
+/** @brief Send a "interested" message to a peer
+ * @param peer peer data
+ * @param mailbox destination mailbox
*/
void send_interested(peer_t peer, const char *mailbox)
{
- msg_task_t task =
- task_message_new(MESSAGE_INTERESTED, peer->hostname, peer->mailbox,
- peer->id, task_message_size(MESSAGE_INTERESTED));
+ msg_task_t task = task_message_new(MESSAGE_INTERESTED, peer->hostname, peer->mailbox, peer->id,
+ task_message_size(MESSAGE_INTERESTED));
MSG_task_dsend(task, mailbox, task_message_free);
XBT_DEBUG("Sending INTERESTED to %s", mailbox);
-
}
-/**
- * Send a "not interested" message to a peer
- * @param peer peer data
- * @param mailbox destination mailbox
+/** @brief Send a "not interested" message to a peer
+ * @param peer peer data
+ * @param mailbox destination mailbox
*/
void send_notinterested(peer_t peer, const char *mailbox)
{
- msg_task_t task =
- task_message_new(MESSAGE_NOTINTERESTED, peer->hostname, peer->mailbox,
- peer->id, task_message_size(MESSAGE_NOTINTERESTED));
+ msg_task_t task = task_message_new(MESSAGE_NOTINTERESTED, peer->hostname, peer->mailbox, peer->id,
+ task_message_size(MESSAGE_NOTINTERESTED));
MSG_task_dsend(task, mailbox, task_message_free);
XBT_DEBUG("Sending NOTINTERESTED to %s", mailbox);
-
}
-/**
- * Send a handshake message to all the peers the peer has.
- * @param peer peer data
+/** @brief Send a handshake message to all the peers the peer has.
+ * @param peer peer data
*/
void send_handshake_all(peer_t peer)
{
xbt_dict_cursor_t cursor = NULL;
char *key;
xbt_dict_foreach(peer->peers, cursor, key, remote_peer) {
- msg_task_t task =
- task_message_new(MESSAGE_HANDSHAKE, peer->hostname, peer->mailbox,
- peer->id, task_message_size(MESSAGE_HANDSHAKE));
+ msg_task_t task = task_message_new(MESSAGE_HANDSHAKE, peer->hostname, peer->mailbox, peer->id,
+ task_message_size(MESSAGE_HANDSHAKE));
MSG_task_dsend(task, remote_peer->mailbox, task_message_free);
XBT_DEBUG("Sending a HANDSHAKE to %s", remote_peer->mailbox);
}
}
-/**
- * Send a "handshake" message to an user
- * @param peer peer data
- * @param mailbox mailbox where to we send the message
+/** @brief Send a "handshake" message to an user
+ * @param peer peer data
+ * @param mailbox mailbox where to we send the message
*/
void send_handshake(peer_t peer, const char *mailbox)
{
- msg_task_t task =
- task_message_new(MESSAGE_HANDSHAKE, peer->hostname, peer->mailbox,
- peer->id, task_message_size(MESSAGE_HANDSHAKE));
+ msg_task_t task = task_message_new(MESSAGE_HANDSHAKE, peer->hostname, peer->mailbox, peer->id,
+ task_message_size(MESSAGE_HANDSHAKE));
MSG_task_dsend(task, mailbox, task_message_free);
XBT_DEBUG("Sending a HANDSHAKE to %s", mailbox);
}
-/**
- * Send a "choked" message to a peer.
- */
+/** Send a "choked" message to a peer. */
void send_choked(peer_t peer, const char *mailbox)
{
XBT_DEBUG("Sending a CHOKE to %s", mailbox);
- msg_task_t task =
- task_message_new(MESSAGE_CHOKE, peer->hostname, peer->mailbox,
- peer->id, task_message_size(MESSAGE_CHOKE));
+ msg_task_t task = task_message_new(MESSAGE_CHOKE, peer->hostname, peer->mailbox, peer->id,
+ task_message_size(MESSAGE_CHOKE));
MSG_task_dsend(task, mailbox, task_message_free);
}
-/**
- * Send a "unchoked" message to a peer
- */
+/** Send a "unchoked" message to a peer */
void send_unchoked(peer_t peer, const char *mailbox)
{
XBT_DEBUG("Sending a UNCHOKE to %s", mailbox);
- msg_task_t task =
- task_message_new(MESSAGE_UNCHOKE, peer->hostname, peer->mailbox,
- peer->id, task_message_size(MESSAGE_UNCHOKE));
+ msg_task_t task = task_message_new(MESSAGE_UNCHOKE, peer->hostname, peer->mailbox, peer->id,
+ task_message_size(MESSAGE_UNCHOKE));
MSG_task_dsend(task, mailbox, task_message_free);
}
-/**
- * Send a "HAVE" message to all peers we are connected to
- */
+/** Send a "HAVE" message to all peers we are connected to */
void send_have(peer_t peer, int piece)
{
XBT_DEBUG("Sending HAVE message to all my peers");
xbt_dict_cursor_t cursor = NULL;
char *key;
xbt_dict_foreach(peer->peers, cursor, key, remote_peer) {
- msg_task_t task =
- task_message_index_new(MESSAGE_HAVE, peer->hostname, peer->mailbox,
- peer->id, piece, task_message_size(MESSAGE_HAVE));
+ msg_task_t task = task_message_index_new(MESSAGE_HAVE, peer->hostname, peer->mailbox, peer->id, piece,
+ task_message_size(MESSAGE_HAVE));
MSG_task_dsend(task, remote_peer->mailbox, task_message_free);
}
}
-/**
- * Send a bitfield message to all the peers the peer has.
- * @param peer peer data
+/** @brief Send a bitfield message to all the peers the peer has.
+ * @param peer peer data
*/
void send_bitfield(peer_t peer, const char *mailbox)
{
XBT_DEBUG("Sending a BITFIELD to %s", mailbox);
- msg_task_t task =
- task_message_bitfield_new(peer->hostname, peer->mailbox, peer->id,
- peer->bitfield, FILE_PIECES);
- //Async send and append to pending sends
- msg_comm_t comm = MSG_task_isend(task, mailbox);
- xbt_dynar_push(peer->pending_sends, &comm);
-}
-
-/**
- * Send a "request" message to a pair, containing a request for a piece
- */
-void send_request(peer_t peer, const char *mailbox, int piece, int block_index,
- int block_length)
-{
- XBT_DEBUG("Sending a REQUEST to %s for piece %d (%d,%d)", mailbox, piece,
- block_index, block_length);
- msg_task_t task =
- task_message_request_new(peer->hostname, peer->mailbox, peer->id, piece,
- block_index, block_length);
+ msg_task_t task = task_message_bitfield_new(peer->hostname, peer->mailbox, peer->id, peer->bitfield, FILE_PIECES);
MSG_task_dsend(task, mailbox, task_message_free);
}
-/**
- * Send a "piece" message to a pair, containing a piece of the file
- */
-void send_piece(peer_t peer, const char *mailbox, int piece, int stalled,
- int block_index, int block_length)
+/** Send a "request" message to a pair, containing a request for a piece */
+void send_request(peer_t peer, const char *mailbox, int piece, int block_index, int block_length)
{
- XBT_DEBUG("Sending the PIECE %d (%d,%d) to %s", piece, block_index,
- block_length, mailbox);
- xbt_assert(piece >= 0, "Tried to send a piece that doesn't exist.");
- xbt_assert((peer->bitfield[piece] == '1'),
- "Tried to send a piece that we doesn't have.");
- msg_task_t task =
- task_message_piece_new(peer->hostname, peer->mailbox, peer->id, piece,
- stalled, block_index, block_length, BLOCK_SIZE);
+ XBT_DEBUG("Sending a REQUEST to %s for piece %d (%d,%d)", mailbox, piece, block_index, block_length);
+ msg_task_t task = task_message_request_new(peer->hostname, peer->mailbox, peer->id, piece, block_index, block_length);
MSG_task_dsend(task, mailbox, task_message_free);
}
-int in_current_pieces(peer_t peer, int piece)
+/** Send a "piece" message to a pair, containing a piece of the file */
+void send_piece(peer_t peer, const char *mailbox, int piece, int block_index, int block_length)
{
- unsigned i;
- int is_in = 0, peer_piece;
- xbt_dynar_foreach(peer->current_pieces, i, peer_piece) {
- if (peer_piece == piece) {
- is_in = 1;
- break;
- }
- }
- return is_in;
+ XBT_DEBUG("Sending the PIECE %d (%d,%d) to %s", piece, block_index, block_length, mailbox);
+ xbt_assert(piece >= 0, "Tried to send a piece that doesn't exist.");
+ xbt_assert((peer->bitfield[piece] == '1'), "Tried to send a piece that we doesn't have.");
+ msg_task_t task = task_message_piece_new(peer->hostname, peer->mailbox, peer->id, piece, block_index, block_length,
+ BLOCK_SIZE);
+ MSG_task_dsend(task, mailbox, task_message_free);
}
