- /* Copyright (c) 2012. The SimGrid Team.
- * All rights reserved. */
+/* Copyright (c) 2012. 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 "messages.h"
#include <msg/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
/**
+ * Number of blocks asked by each request
+ */
+#define BLOCKS_REQUESTED 2
+
+
+static const int FILE_SIZE = FILE_PIECES * PIECES_BLOCKS * BLOCK_SIZE;
+
+void request_new_piece_to_peer(peer_t peer, connection_t remote_peer);
+void send_request_to_peer(peer_t peer, connection_t remote_peer, int piece);
+void remove_current_piece(peer_t peer, connection_t remote_peer,
+ int current_piece);
+
+
+ /**
* Peer main function
*/
int peer(int argc, char *argv[])
XBT_DEBUG("Got %d peers from the tracker", xbt_dict_length(peer.peers));
XBT_DEBUG("Here is my current status: %s", peer.bitfield);
peer.begin_receive_time = MSG_get_clock();
+ MSG_mailbox_set_async(peer.mailbox);
if (has_finished(peer.bitfield)) {
peer.pieces = FILE_PIECES;
send_handshake_all(&peer);
seed_loop(&peer, deadline);
} else {
leech_loop(&peer, deadline);
+// XBT_INFO("%d becomes a seeder", peer.id);
seed_loop(&peer, deadline);
}
} else {
*/
send_handshake_all(peer);
//Wait for at least one "bitfield" message.
- wait_for_pieces(peer, deadline);
+// 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) {
+// XBT_INFO("irecv");
peer->task_received = NULL;
- peer->comm_received = MSG_task_irecv(&peer->task_received, peer->mailbox);
+ peer->comm_received =
+ MSG_task_irecv(&peer->task_received, peer->mailbox);
}
if (MSG_comm_test(peer->comm_received)) {
+// XBT_INFO("comm_test OK");
msg_error_t status = MSG_comm_get_status(peer->comm_received);
MSG_comm_destroy(peer->comm_received);
peer->comm_received = NULL;
if (status == MSG_OK) {
- handle_message(peer, peer->task_received);
+ 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;
+ update_choked_peers(peer);
+ next_choked_update += UPDATE_CHOKED_INTERVAL;
} else {
- MSG_process_sleep(1);
+ MSG_process_sleep(1);
}
}
}
while (MSG_get_clock() < deadline) {
if (peer->comm_received == NULL) {
peer->task_received = NULL;
- peer->comm_received = MSG_task_irecv(&peer->task_received, peer->mailbox);
+ peer->comm_received =
+ MSG_task_irecv(&peer->task_received, peer->mailbox);
}
if (MSG_comm_test(peer->comm_received)) {
msg_error_t status = MSG_comm_get_status(peer->comm_received);
MSG_comm_destroy(peer->comm_received);
peer->comm_received = NULL;
if (status == MSG_OK) {
- handle_message(peer, peer->task_received);
+ handle_message(peer, peer->task_received);
}
} else {
if (MSG_get_clock() >= next_choked_update) {
- update_choked_peers(peer);
- //TODO: Change the choked peer algorithm when seeding.
- next_choked_update += UPDATE_CHOKED_INTERVAL;
+ update_choked_peers(peer);
+ //TODO: Change the choked peer algorithm when seeding.
+ next_choked_update += UPDATE_CHOKED_INTERVAL;
} else {
- MSG_process_sleep(1);
+ MSG_process_sleep(1);
}
}
}
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_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;
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_task_send_with_timeout(task_send, TRACKER_MAILBOX,
+ GET_PEERS_TIMEOUT);
if (status == MSG_OK) {
send_success = 1;
}
int peer_id;
//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);
+ if (peer_id != peer->id)
+ xbt_dict_set_ext(peer->peers, (char *) &peer_id, sizeof(int),
+ connection_new(peer_id), NULL);
}
success = 1;
//free the communication and the task
if (seed) {
memset(peer->bitfield, '1', sizeof(char) * (FILE_PIECES + 1));
memset(peer->bitfield_blocks, '1',
- sizeof(char) * FILE_PIECES * (PIECES_BLOCKS));
+ 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));
+ 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_CreateStream("");
peer->comm_received = NULL;
peer->round = 0;
xbt_free(peer->pieces_count);
xbt_free(peer->bitfield);
xbt_free(peer->bitfield_blocks);
+
+ RngStream_DeleteStream(&peer->stream);
}
/**
*/
int has_finished(char *bitfield)
{
- return ((memchr(bitfield, '0', sizeof(char) * FILE_PIECES) == NULL) ? 1 : 0);
+ return ((memchr(bitfield, '0', sizeof(char) * FILE_PIECES) ==
+ NULL) ? 1 : 0);
+}
+
+int nb_interested_peers(peer_t peer)
+{
+ 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;
}
/**
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);
+ 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));
+ 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);
}
}
+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
* @param peer Peer data
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));
+ 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);
+ 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);
+ connection_new(message->peer_id), NULL);
send_handshake(peer, message->mailbox);
}
//Send our bitfield to the peer
break;
case MESSAGE_BITFIELD:
XBT_DEBUG("Recieved a BITFIELD message from %s (%s)", message->mailbox,
- message->issuer_host_name);
+ 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);
+ message->issuer_host_name);
xbt_assert((remote_peer != NULL),
- "A non-in-our-list peer has sent us a message. WTH ?");
+ "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_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 ?");
+ "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 ?");
+ "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);
+ message->issuer_host_name);
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 ?");
+ "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);
+ message->issuer_host_name);
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);
+ 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");
- if (remote_peer->bitfield == NULL)
- return;
+ && 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");
+ && 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);
+ message->mailbox, message->issuer_host_name, message->peer_id,
+ 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, 0,
+ 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);
+ 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");
+ && 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);
+ 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);
+ 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);
- 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);
- //Setting the fact that we have the piece
- peer->bitfield[message->index] = '1';
- peer->pieces++;
- XBT_DEBUG("My status is now %s", peer->bitfield);
- //Sending the information to all the peers we are connected to
- send_have(peer, message->index);
- //sending UNINTERSTED to peers that doesn't have what we want.
- update_interested_after_receive(peer);
- }
+ update_bitfield_blocks(peer, message->index, message->block_index,
+ message->block_length);
+ if (piece_complete(peer, message->index)) {
+ //Removing the piece from our piece list
+ remove_current_piece(peer, remote_peer, message->index);
+ //Setting the fact that we have the piece
+ peer->bitfield[message->index] = '1';
+ peer->pieces++;
+ XBT_DEBUG("My status is now %s", peer->bitfield);
+ //Sending the information to all the peers we are connected to
+ 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_DEBUG("However, we already have it");
+ 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));
+ 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)
+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);
+ }
+}
+
+void remove_current_piece(peer_t peer, connection_t remote_peer,
+ int current_piece)
+{
+ int piece_index = -1, piece, 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;
}
/**
}
}
+
+
/**
- * 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.
+ * Return the piece to be downloaded
+ * There are two cases (as described in "Bittorrent Architecture Protocol", Ryan Toole :
+ * 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
+ * Note: "end game mode" policy is not implemented
+ * @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;
+ // TODO : add strict priority policy
+
+ if (xbt_dynar_length(peer->current_pieces) >= (FILE_PIECES - peer->pieces)) { // end game mode
+ return -1;
}
- if (1 || peer->pieces < 3) {
- int i = 0;
+ if (peer->pieces < 4 && is_interested_and_free(peer, remote_peer)) { // Random first policy
+ int piece = 0;
do {
- peer->current_piece =
- RngStream_RandInt(peer->stream, 0, FILE_PIECES - 1);;
- i++;
+ piece = RngStream_RandInt(peer->stream, 0, FILE_PIECES - 1);;
} 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;
+ (peer->bitfield[piece] == '0'
+ && remote_peer->bitfield[piece] == '1'
+ && !in_current_pieces(peer, piece)));
+ return piece;
+ } else { // Rarest first policy
+ int i, min_piece = -1;
+ short min = SHRT_MAX;
for (i = 0; i < FILE_PIECES; i++) {
- if (peer->bitfield[i] == '0') {
- min = peer->pieces_count[i];
- min_id = i;
- break;
+ 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_piece = i;
}
}
- 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') {
- min = peer->pieces_count[i];
- min_id = i;
- }
- }
- peer->current_piece = min_id;
+ // TODO: add randomness when selecting a rarest piece
+ return min_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
*/
void update_choked_peers(peer_t peer)
{
+ if (nb_interested_peers(peer) == 0)
+ return;
+ // if(xbt_dict_size(peer->active_peers) > 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;
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_length(peer->active_peers) > 0) {
- 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));
+ 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 unchoke the least 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) {
- unchoke_time = connection->last_unchoke;
- peer_choosed = connection;
+ if (connection->last_unchoke < unchoke_time && connection->interested
+ && connection->choked_upload) {
+ unchoke_time = connection->last_unchoke;
+ peer_choosed = connection;
}
}
} else {
if (peer->round == 0) {
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 i = 0;
- connection_t connection;
- xbt_dict_foreach(peer->peers, cursor, key, connection) {
- if (i == id_chosen) {
- peer_choosed = connection;
- break;
- }
- i++;
- }
- xbt_dict_cursor_free(&cursor);
- if (peer_choosed->interested == 0) {
- peer_choosed = NULL;
- }
- j++;
+ //We choose a random peer to unchoke.
+ 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) {
+ if (i == id_chosen) {
+ peer_choosed = connection;
+ break;
+ }
+ i++;
+ }
+ xbt_dict_cursor_free(&cursor);
+ if (!peer_choosed->interested || !peer_choosed->choked_upload) {
+ peer_choosed = NULL;
+ }
+ j++;
} while (peer_choosed == NULL && j < MAXIMUM_PAIRS);
} else {
//Use the "fastest download" policy.
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) {
- peer_choosed = connection;
- fastest_speed = connection->peer_speed;
- }
+ 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 (xbt_dict_size(peer->peers) > 0)
+ // xbt_assert((xbt_dict_size(peer->active_peers) != 0),
+ // "No more active peers !");
+
+ // if (peer_choked != NULL && peer_choked->choked_upload != 0)
+ // peer_choked = NULL;
+ // if (peer_choosed != NULL && peer_choosed->choked_upload == 0)
+ // peer_choosed = NULL;
+
+ 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_dict_remove_ext(peer->active_peers, key_choked, sizeof(int));
+ 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);
+ }
+ }
}
/**
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') {
- interested = 1;
- break;
- }
+ int i;
+ for (i = 0; i < FILE_PIECES; i++) {
+ if (connection->bitfield[i] == '1' && peer->bitfield[i] == '0') {
+ interested = 1;
+ break;
+ }
}
- if (!interested) {
- connection->am_interested = 0;
- send_notinterested(peer, connection->mailbox);
+ 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)
+ 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);
+ && 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 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)
{
return -1;
}
+/**
+ * Returns a piece that is stored by the remote peer but not by the local peer.
+ * -1 otherwise.
+ */
+int is_interested(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') {
+ return 1;
+ }
+ }
+ return 0;
+}
+
+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;
+}
+
+
/**
* 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)
+void send_request_to_peer(peer_t peer, connection_t remote_peer, int piece)
{
+ remote_peer->current_piece = piece;
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;
- }
- }
+ 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);
}
}
+
/**
- * Find the peers that have the current interested piece and send them
- * the "interested" message
+ * Indicates if a piece is currently being downloaded by the peer.
*/
-void send_interested_to_peers(peer_t peer)
+int in_current_pieces(peer_t 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);
+ 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;
}
+
+
+
+/***********************************************************
+ *
+ * Low level message functions
+ *
+ ***********************************************************/
+
+
+
/**
* Send a "interested" message to a peer
* @param peer peer data
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));
+ 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);
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));
+ 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);
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));
+ 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);
}
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));
+ 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);
}
{
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));
+ task_message_new(MESSAGE_CHOKE, peer->hostname, peer->mailbox,
+ peer->id, task_message_size(MESSAGE_CHOKE));
MSG_task_dsend(task, mailbox, task_message_free);
}
{
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));
+ task_message_new(MESSAGE_UNCHOKE, peer->hostname, peer->mailbox,
+ peer->id, task_message_size(MESSAGE_UNCHOKE));
MSG_task_dsend(task, mailbox, task_message_free);
}
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));
+ 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);
}
}
{
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);
+ 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)
+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);
+ block_index, block_length);
msg_task_t task =
- task_message_request_new(peer->hostname, peer->mailbox, peer->id, piece,
- block_index, block_length);
+ task_message_request_new(peer->hostname, peer->mailbox, peer->id, piece,
+ block_index, block_length);
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)
+ int block_index, int block_length)
{
XBT_DEBUG("Sending the PIECE %d (%d,%d) to %s", piece, block_index,
- block_length, mailbox);
+ 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.");
+ "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);
+ task_message_piece_new(peer->hostname, peer->mailbox, peer->id, piece,
+ stalled, block_index, block_length, BLOCK_SIZE);
MSG_task_dsend(task, mailbox, task_message_free);
}
-
-int in_current_pieces(peer_t peer, int piece)
-{
- 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;
-}
