X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/0f123dd4d0d60d0c57bcae6f3629c83e32549b39..65b0ef3e4abf59f79ff89fa7644aff2451922729:/examples/msg/bittorrent/peer.c diff --git a/examples/msg/bittorrent/peer.c b/examples/msg/bittorrent/peer.c index 5dc1078c54..88b287f69b 100644 --- a/examples/msg/bittorrent/peer.c +++ b/examples/msg/bittorrent/peer.c @@ -1,4 +1,4 @@ - /* Copyright (c) 2012. The SimGrid Team. +/* Copyright (c) 2012. The SimGrid Team. * All rights reserved. */ /* This program is free software; you can redistribute it and/or modify it @@ -9,589 +9,831 @@ #include "messages.h" #include #include +#include -XBT_LOG_NEW_DEFAULT_CATEGORY(msg_peers, - "Messages specific for the peers"); +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 + */ +#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[]) { - s_peer_t peer; - //Check arguments - xbt_assert(argc == 3 || argc == 4, "Wrong number of arguments"); - //Build peer object - if (argc == 4) { - peer_init(&peer, atoi(argv[1]),1); - } - else { - peer_init(&peer, atoi(argv[1]),0); - } - //Retrieve deadline - double deadline = atof(argv[2]); - 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. - if (get_peers_data(&peer)) { - 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(); - if (has_finished(peer.bitfield)) { - peer.pieces = FILE_PIECES; - send_handshake_all(&peer); - seed_loop(&peer,deadline); - } - else { - leech_loop(&peer,deadline); - seed_loop(&peer,deadline); - } - } - else { - XBT_INFO("Couldn't contact the tracker."); - } - - XBT_INFO("Here is my current status: %s", peer.bitfield); - if (peer.comm_received) { - MSG_comm_destroy(peer.comm_received); - } - - peer_free(&peer); - return 0; +int peer(int argc, char *argv[]) +{ + s_peer_t peer; + //Check arguments + xbt_assert(argc == 3 || argc == 4, "Wrong number of arguments"); + //Build peer object + if (argc == 4) { + peer_init(&peer, atoi(argv[1]), 1); + } else { + peer_init(&peer, atoi(argv[1]), 0); + } + //Retrieve deadline + double deadline = atof(argv[2]); + 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. + if (get_peers_data(&peer)) { + 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 { + XBT_INFO("Couldn't contact the tracker."); + } + + XBT_INFO("Here is my current status: %s", peer.bitfield); + if (peer.comm_received) { + MSG_comm_destroy(peer.comm_received); + } + + peer_free(&peer); + return 0; } + /** * 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) { - double next_choked_update = MSG_get_clock() + UPDATE_CHOKED_INTERVAL; - XBT_DEBUG("Start downloading."); - /* - * Send a "handshake" message to all the peers it got - * (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; - 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); - } - } - else { - 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); - } - } - } +void leech_loop(peer_t peer, double deadline) +{ + double next_choked_update = MSG_get_clock() + UPDATE_CHOKED_INTERVAL; + XBT_DEBUG("Start downloading."); + /* + * Send a "handshake" message to all the peers it got + * (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) { +// XBT_INFO("irecv"); + peer->task_received = NULL; + 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); + } + } else { + handle_pending_sends(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); + } + } + } } + /** * 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) { - double next_choked_update = MSG_get_clock() + UPDATE_CHOKED_INTERVAL; - XBT_DEBUG("Start seeding."); - //start the main seed loop - 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); - } - 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); - } - } - 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; - } - else { - MSG_process_sleep(1); - } - } - } +void seed_loop(peer_t peer, double deadline) +{ + double next_choked_update = MSG_get_clock() + UPDATE_CHOKED_INTERVAL; + XBT_DEBUG("Start seeding."); + //start the main seed loop + 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); + } + 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); + } + } 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; + } else { + MSG_process_sleep(1); + } + } + } } + /** * 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); - //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); - if (status == MSG_OK) { - send_success = 1; - } - } - while (!success && MSG_get_clock() < timeout) { - comm_received = MSG_task_irecv(&task_received,peer->mailbox_tracker); - msg_error_t status = MSG_comm_wait(comm_received, GET_PEERS_TIMEOUT); - if (status == MSG_OK) { - tracker_task_data_t data = MSG_task_get_data(task_received); - int i, 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); - } - success = 1; - //free the communication and the task - MSG_comm_destroy(comm_received); - tracker_task_data_free(data); - MSG_task_destroy(task_received); - comm_received = NULL; - } - } - - return success; +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); + //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); + if (status == MSG_OK) { + send_success = 1; + } + } + while (!success && MSG_get_clock() < timeout) { + comm_received = MSG_task_irecv(&task_received, peer->mailbox_tracker); + msg_error_t status = MSG_comm_wait(comm_received, GET_PEERS_TIMEOUT); + if (status == MSG_OK) { + tracker_task_data_t data = MSG_task_get_data(task_received); + unsigned i; + 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); + } + success = 1; + //free the communication and the task + MSG_comm_destroy(comm_received); + tracker_task_data_free(data); + MSG_task_destroy(task_received); + comm_received = NULL; + } + } + + 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. */ -void peer_init(peer_t peer, int id, int seed) { - peer->id = id; - sprintf(peer->mailbox,"%d",id); - sprintf(peer->mailbox_tracker,"tracker_%d",id); - peer->peers = xbt_dict_new(); - peer->active_peers = xbt_dict_new(); - peer->hostname = MSG_host_get_name(MSG_host_self()); +void peer_init(peer_t peer, int id, int seed) +{ + peer->id = id; + sprintf(peer->mailbox, "%d", id); + sprintf(peer->mailbox_tracker, "tracker_%d", id); + peer->peers = xbt_dict_new(); + peer->active_peers = xbt_dict_new(); + peer->hostname = MSG_host_get_name(MSG_host_self()); + + peer->bitfield = xbt_new(char, FILE_PIECES + 1); + 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)); + } else { + memset(peer->bitfield, '0', sizeof(char) * (FILE_PIECES + 1)); + memset(peer->bitfield_blocks, '0', + sizeof(char) * FILE_PIECES * (PIECES_BLOCKS)); + } - peer->bitfield = xbt_new(char,FILE_PIECES + 1); - 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)); - } - else { - memset(peer->bitfield,'0',sizeof(char) * (FILE_PIECES + 1)); - memset(peer->bitfield_blocks,'0',sizeof(char) * FILE_PIECES * (PIECES_BLOCKS)); - } + peer->bitfield[FILE_PIECES] = '\0'; + peer->pieces = 0; - peer->bitfield[FILE_PIECES] = '\0'; - peer->pieces = 0; + peer->pieces_count = xbt_new0(short, FILE_PIECES); - peer->pieces_count = xbt_new0(short,FILE_PIECES); - peer->pieces_requested = 0; + peer->current_pieces = xbt_dynar_new(sizeof(int), NULL); - peer->current_pieces = xbt_dynar_new(sizeof(int),NULL); - peer->current_piece = -1; + peer->stream = RngStream_CreateStream(""); + peer->comm_received = NULL; - peer->stream = RngStream_CreateStream(""); - peer->comm_received = NULL; + peer->round = 0; - peer->round = 0; + peer->pending_sends = xbt_dynar_new(sizeof(msg_comm_t), NULL); } + /** * Destroys a poor peer object. */ -void peer_free(peer_t peer) { - char *key; - connection_t connection; - xbt_dict_cursor_t cursor; - xbt_dict_foreach(peer->peers,cursor,key,connection) { - connection_free(connection); - } - xbt_dict_free(&peer->peers); - xbt_dict_free(&peer->active_peers); - xbt_dynar_free(&peer->current_pieces); - xbt_free(peer->pieces_count); - xbt_free(peer->bitfield); - xbt_free(peer->bitfield_blocks); - - RngStream_DeleteStream(&peer->stream); +void peer_free(peer_t peer) +{ + char *key; + connection_t connection; + xbt_dict_cursor_t cursor; + xbt_dict_foreach(peer->peers, cursor, key, connection) { + connection_free(connection); + } + 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); + + RngStream_DeleteStream(&peer->stream); } + /** * 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); +int has_finished(char *bitfield) +{ + 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; } + /** - * Handle a received message sent by another peer + * Handle pending sends and remove those which are done * @param peer Peer data - * @param task task received. */ -void handle_message(peer_t peer, msg_task_t task) { - 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)); - switch (message->type) { - - case MESSAGE_HANDSHAKE: - 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); - 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); - //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); - } - 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 ?"); - //Update the interested state of the peer. - remote_peer->interested = 1; - 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 ?"); - remote_peer->interested = 0; - 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); - 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); - 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); - 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); - } - 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; - 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)) { - remote_peer->am_interested = 1; - send_interested(peer,remote_peer->mailbox); - } - break; - case MESSAGE_REQUEST: - 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); - if (peer->bitfield[message->index] == '1') { - 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); - } - break; - case MESSAGE_PIECE: - 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); - if (piece_complete(peer,message->index)) { - peer->pieces_requested--; - //Removing the piece from our piece list - int piece_index = -1, i, 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); - } - } - else { - XBT_DEBUG("However, we already have it"); - } - } - break; - } - //Update the peer speed. - if (remote_peer) { - 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); +void handle_pending_sends(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); + + 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); + } + } } + /** - * Wait for the node to receive interesting bitfield messages (ie: non empty) - * to be received - * @param deadline peer deadline - * @param peer peer data + * Handle a received message sent by another peer + * @param peer Peer data + * @param task task received. */ -void wait_for_pieces(peer_t peer, double deadline) { - 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) { - message_t message = MSG_task_get_data(peer->task_received); - handle_message(peer,peer->task_received); - if (peer->current_piece != -1) { - finished = 1; - } - } - } +void handle_message(peer_t peer, msg_task_t task) +{ + 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)); + switch (message->type) { + + case MESSAGE_HANDSHAKE: + 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); + 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); + //Update the pieces list + update_pieces_count_from_bitfield(peer, message->bitfield); + //Store the bitfield + remote_peer->bitfield = xbt_strdup(message->bitfield); + 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 ?"); + //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 ?"); + 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); + remote_peer->choked_download = 0; + //Send requests to the peer, since it has unchoked us + 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); + remote_peer->choked_download = 1; + 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(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 && peer->bitfield[message->index] == '0') { + remote_peer->am_interested = 1; + 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"); + 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); + if (peer->bitfield[message->index] == '1') { + 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); + } + break; + case MESSAGE_PIECE: + 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); + 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"); + 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)); + } + peer->begin_receive_time = MSG_get_clock(); + + task_message_free(task); +} + +void request_new_piece_to_peer(peer_t peer, connection_t remote_peer) +{ + 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; } + /** * 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) { - int i; - for (i = 0; i < FILE_PIECES; i++) { - if (bitfield[i] == '1') { - peer->pieces_count[i]++; - } - } +void update_pieces_count_from_bitfield(peer_t peer, char *bitfield) +{ + int i; + for (i = 0; i < FILE_PIECES; i++) { + if (bitfield[i] == '1') { + peer->pieces_count[i]++; + } + } } + + + /** - * 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 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 - */ -void update_current_piece(peer_t peer) { - if (xbt_dynar_length(peer->current_pieces) >= (FILE_PIECES - peer->pieces)) { - return; - } - 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; - for (i = 0; i < FILE_PIECES; i++) { - if (peer->bitfield[i] == '0') { - min = peer->pieces_count[i]; - min_id = i; - break; - } - } - 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; - } - 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.")); + * 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 + */ +int select_piece_to_download(peer_t peer, connection_t remote_peer) +{ + 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)) { + 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; + } + // 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' && remote_peer->bitfield[i] == '1' + && !in_current_pieces(peer, i)) { + 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' + && !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]; + } + 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++; + } + } + xbt_assert(piece != -1 + || !is_interested_and_free(peer, remote_peer), "WTF !!!"); + return piece; + } } + + /** * 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) { - //update the current round - peer->round = (peer->round + 1) % 3; - int i; - char *key; - connection_t peer_choosed = 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)); - } - xbt_dict_cursor_free(&cursor); - - /** - * 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; +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, *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_choked = xbt_dict_cursor_get_key(cursor); + peer_choked = xbt_dict_cursor_get_data(cursor); + } + xbt_dict_cursor_free(&cursor); - xbt_dict_foreach(peer->peers,cursor,key,connection) { - if (connection->last_unchoke < unchoke_time && connection->interested) { - unchoke_time = connection->last_unchoke; - peer_choosed = connection; - } - } - } - else { - //Random optimistic unchoking - 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++; - } while (peer_choosed == NULL && j < MAXIMUM_PAIRS); + /** + * 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 + && connection->choked_upload) { + unchoke_time = connection->last_unchoke; + peer_choosed = connection; } - else { - //Use the "fastest download" policy. + } + } else { + //Random optimistic unchoking + 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; - double fastest_speed = 0.0; - xbt_dict_foreach(peer->peers,cursor,key,connection) { - if (connection->peer_speed > fastest_speed && connection->choked_upload && connection->interested) { + xbt_dict_foreach(peer->peers, cursor, key, connection) { + if (i == id_chosen) { peer_choosed = connection; - fastest_speed = connection->peer_speed; + 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 (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) { - 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); + 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 */ -void update_interested_after_receive(peer_t peer) { - char *key; - xbt_dict_cursor_t cursor; - connection_t connection; - int interested, cpt, piece; - xbt_dict_foreach(peer->peers, cursor, key, connection) { - interested = 0; - if (connection->am_interested) { - //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; - } - } - if (!interested) { - 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_interested_after_receive(peer_t peer) +{ + char *key; + xbt_dict_cursor_t cursor; + connection_t connection; + unsigned cpt; + int interested, piece; + 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. + int i; + for (i = 0; i < FILE_PIECES; i++) { + if (connection->bitfield[i] == '1' && peer->bitfield[i] == '0') { + interested = 1; + break; + } + } + 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 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 */ -int piece_complete(peer_t peer, int index) { +int piece_complete(peer_t peer, int index) +{ int i; for (i = 0; i < PIECES_BLOCKS; i++) { if (peer->bitfield_blocks[index * PIECES_BLOCKS + i] == '0') { @@ -600,10 +842,13 @@ int piece_complete(peer_t peer, int index) { } 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 get_first_block(peer_t peer, int piece) +{ int i; for (i = 0; i < PIECES_BLOCKS; i++) { if (peer->bitfield_blocks[piece * PIECES_BLOCKS + i] == '0') { @@ -612,155 +857,251 @@ int get_first_block(peer_t peer, int piece) { } return -1; } + +/** + * Indicates if the remote peer has a piece not stored by the local peer + */ +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; +} + +/** + * 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; +} + + /** * 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) { - int i, 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; - } - } - } +void send_request_to_peer(peer_t peer, connection_t remote_peer, int piece) +{ + remote_peer->current_piece = piece; + unsigned i; + 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 - */ -void send_interested_to_peers(peer_t peer) { - 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); - MSG_task_dsend(task,connection->mailbox,task_message_free); - XBT_DEBUG("Send INTERESTED to %s",connection->mailbox); - } - } - peer->current_piece = -1; - peer->pieces_requested++; + * 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; + } + } + return 0; } + + + + +/*********************************************************** + * + * Low level message functions + * + ***********************************************************/ + + + /** * 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); - MSG_task_dsend(task,mailbox,task_message_free); - XBT_DEBUG("Sending INTERESTED to %s",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_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 */ -void send_notinterested(peer_t peer, const char *mailbox) { - msg_task_t task = task_message_new(MESSAGE_NOTINTERESTED, peer->hostname, peer->mailbox, peer->id); - MSG_task_dsend(task,mailbox,task_message_free); - XBT_DEBUG("Sending NOTINTERESTED 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)); + 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 */ -void send_handshake_all(peer_t peer) { - connection_t remote_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); - MSG_task_dsend(task,remote_peer->mailbox,task_message_free); - XBT_DEBUG("Sending a HANDSHAKE to %s",remote_peer->mailbox); - } +void send_handshake_all(peer_t peer) +{ + connection_t remote_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_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 */ -void send_handshake(peer_t peer, const char *mailbox) { - msg_task_t task = task_message_new(MESSAGE_HANDSHAKE, peer->hostname, peer->mailbox,peer->id); - MSG_task_dsend(task,mailbox,task_message_free); - XBT_DEBUG("Sending a HANDSHAKE to %s",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)); + MSG_task_dsend(task, mailbox, task_message_free); + XBT_DEBUG("Sending a HANDSHAKE to %s", mailbox); } + /** * 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); - MSG_task_dsend(task,mailbox,task_message_free); +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_dsend(task, mailbox, task_message_free); } + /** * 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); - MSG_task_dsend(task,mailbox,task_message_free); +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_dsend(task, mailbox, task_message_free); } + /** * 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"); - connection_t remote_peer; - 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); - MSG_task_dsend(task,remote_peer->mailbox,task_message_free); - } +void send_have(peer_t peer, int piece) +{ + XBT_DEBUG("Sending HAVE message to all my peers"); + connection_t remote_peer; + 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_dsend(task, remote_peer->mailbox, task_message_free); + } } + /** * 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); - MSG_task_dsend(task,mailbox,task_message_free); +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_dsend(task,mailbox,task_message_free); +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_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) { - 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); - MSG_task_dsend(task,mailbox,task_message_free); -} - -int in_current_pieces(peer_t peer, int piece) { - int is_in = 0, i, peer_piece; - xbt_dynar_foreach(peer->current_pieces,i, peer_piece) { - if (peer_piece == piece) { - is_in = 1; - break; - } - } - return is_in; +void send_piece(peer_t peer, const char *mailbox, int piece, int stalled, + 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); + MSG_task_dsend(task, mailbox, task_message_free); }