opentracker/trackerlogic.c

/* This software was written by Dirk Engling <erdgeist@erdgeist.org>
   It is considered beerware. Prost. Skol. Cheers or whatever.

   $id$ */

/* System */
#include <arpa/inet.h>
#include <errno.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

/* Libowfat */
#include "array.h"
#include "byte.h"
#include "io.h"
#include "iob.h"
#include "ip6.h"

/* Opentracker */
#include "ot_accesslist.h"
#include "ot_clean.h"
#include "ot_fullscrape.h"
#include "ot_http.h"
#include "ot_livesync.h"
#include "ot_mutex.h"
#include "ot_stats.h"
#include "ot_vector.h"
#include "trackerlogic.h"

/* Forward declaration */
size_t return_peers_for_torrent(struct ot_workstruct *ws, ot_torrent *torrent, size_t amount, char *reply, PROTO_FLAG proto);

void   free_peerlist(ot_peerlist *peer_list) {
  if (peer_list->peers.data) {
    if (OT_PEERLIST_HASBUCKETS(peer_list))
      vector_clean_list((ot_vector *)peer_list->peers.data, peer_list->peers.size);
    else
      free(peer_list->peers.data);
  }
  free(peer_list);
}

void add_torrent_from_saved_state(ot_hash const hash, ot_time base, size_t down_count) {
  int         exactmatch;
  ot_torrent *torrent;
  ot_vector  *torrents_list = mutex_bucket_lock_by_hash(hash);

  if (!accesslist_hashisvalid(hash))
    return mutex_bucket_unlock_by_hash(hash, 0);

  torrent = vector_find_or_insert(torrents_list, (void *)hash, sizeof(ot_torrent), OT_HASH_COMPARE_SIZE, &exactmatch);
  if (!torrent || exactmatch)
    return mutex_bucket_unlock_by_hash(hash, 0);

  /* Create a new torrent entry, then */
  byte_zero(torrent, sizeof(ot_torrent));
  memcpy(torrent->hash, hash, sizeof(ot_hash));

  if (!(torrent->peer_list6 = malloc(sizeof(ot_peerlist))) || !(torrent->peer_list4 = malloc(sizeof(ot_peerlist)))) {
    vector_remove_torrent(torrents_list, torrent);
    return mutex_bucket_unlock_by_hash(hash, 0);
  }

  byte_zero(torrent->peer_list6, sizeof(ot_peerlist));
  byte_zero(torrent->peer_list4, sizeof(ot_peerlist));
  torrent->peer_list6->base       = base;
  torrent->peer_list4->base       = base;
  torrent->peer_list6->down_count = down_count;
  torrent->peer_list4->down_count = down_count;

  return mutex_bucket_unlock_by_hash(hash, 1);
}

size_t add_peer_to_torrent_and_return_peers(PROTO_FLAG proto, struct ot_workstruct *ws, size_t amount) {
  int            exactmatch, delta_torrentcount = 0;
  ot_torrent    *torrent;
  ot_peer       *peer_dest;
  ot_vector     *torrents_list = mutex_bucket_lock_by_hash(*ws->hash);
  ot_peerlist   *peer_list;
  size_t         peer_size; /* initialized in next line */
  ot_peer const *peer_src = peer_from_peer6(&ws->peer, &peer_size);

  if (!accesslist_hashisvalid(*ws->hash)) {
    mutex_bucket_unlock_by_hash(*ws->hash, 0);
    if (proto == FLAG_TCP) {
      const char invalid_hash[] = "d14:failure reason63:Requested download is not authorized for use with this tracker.e";
      memcpy(ws->reply, invalid_hash, strlen(invalid_hash));
      return strlen(invalid_hash);
    }
    return 0;
  }

  torrent = vector_find_or_insert(torrents_list, (void *)ws->hash, sizeof(ot_torrent), OT_HASH_COMPARE_SIZE, &exactmatch);
  if (!torrent) {
    mutex_bucket_unlock_by_hash(*ws->hash, 0);
    return 0;
  }

  if (!exactmatch) {
    /* Create a new torrent entry, then */
    byte_zero(torrent, sizeof(ot_torrent));
    memcpy(torrent->hash, *ws->hash, sizeof(ot_hash));

    if (!(torrent->peer_list6 = malloc(sizeof(ot_peerlist))) || !(torrent->peer_list4 = malloc(sizeof(ot_peerlist)))) {
      vector_remove_torrent(torrents_list, torrent);
      mutex_bucket_unlock_by_hash(*ws->hash, 0);
      return 0;
    }

    byte_zero(torrent->peer_list6, sizeof(ot_peerlist));
    byte_zero(torrent->peer_list4, sizeof(ot_peerlist));
    delta_torrentcount = 1;
  } else
    clean_single_torrent(torrent);

  torrent->peer_list6->base = g_now_minutes;
  torrent->peer_list4->base = g_now_minutes;

  peer_list = peer_size == OT_PEER_SIZE6 ? torrent->peer_list6 : torrent->peer_list4;

  /* Check for peer in torrent */
  peer_dest = vector_find_or_insert_peer(&(peer_list->peers), peer_src, peer_size, &exactmatch);
  if (!peer_dest) {
    mutex_bucket_unlock_by_hash(*ws->hash, delta_torrentcount);
    return 0;
  }

  /* Tell peer that it's fresh */
  OT_PEERTIME(ws->peer, OT_PEER_SIZE6) = 0;

  /* Sanitize flags: Whoever claims to have completed download, must be a seeder */
  if ((OT_PEERFLAG(ws->peer) & (PEER_FLAG_COMPLETED | PEER_FLAG_SEEDING)) == PEER_FLAG_COMPLETED)
    OT_PEERFLAG(ws->peer) ^= PEER_FLAG_COMPLETED;

  /* If we hadn't had a match create peer there */
  if (!exactmatch) {

#ifdef WANT_SYNC_LIVE
    if (proto == FLAG_MCA)
      OT_PEERFLAG(ws->peer) |= PEER_FLAG_FROM_SYNC;
    else
      livesync_tell(ws);
#endif

    peer_list->peer_count++;
    if (OT_PEERFLAG(ws->peer) & PEER_FLAG_COMPLETED) {
      peer_list->down_count++;
      stats_issue_event(EVENT_COMPLETED, 0, (uintptr_t)ws);
    }
    if (OT_PEERFLAG(ws->peer) & PEER_FLAG_SEEDING)
      peer_list->seed_count++;

  } else {
    stats_issue_event(EVENT_RENEW, 0, OT_PEERTIME(peer_dest, peer_size));
#ifdef WANT_SPOT_WOODPECKER
    if ((OT_PEERTIME(peer_dest, peer_size) > 0) && (OT_PEERTIME(peer_dest, peer_size) < 20))
      stats_issue_event(EVENT_WOODPECKER, 0, (uintptr_t)&ws->peer);
#endif
#ifdef WANT_SYNC_LIVE
    /* Won't live sync peers that come back too fast. Only exception:
       fresh "completed" reports */
    if (proto != FLAG_MCA) {
      if (OT_PEERTIME(peer_dest, peer_size) > OT_CLIENT_SYNC_RENEW_BOUNDARY ||
          (!(OT_PEERFLAG_D(peer_dest, peer_size) & PEER_FLAG_COMPLETED) && (OT_PEERFLAG(ws->peer) & PEER_FLAG_COMPLETED)))
        livesync_tell(ws);
    }
#endif

    if ((OT_PEERFLAG_D(peer_dest, peer_size) & PEER_FLAG_SEEDING) && !(OT_PEERFLAG(ws->peer) & PEER_FLAG_SEEDING))
      peer_list->seed_count--;
    if (!(OT_PEERFLAG_D(peer_dest, peer_size) & PEER_FLAG_SEEDING) && (OT_PEERFLAG(ws->peer) & PEER_FLAG_SEEDING))
      peer_list->seed_count++;
    if (!(OT_PEERFLAG_D(peer_dest, peer_size) & PEER_FLAG_COMPLETED) && (OT_PEERFLAG(ws->peer) & PEER_FLAG_COMPLETED)) {
      peer_list->down_count++;
      stats_issue_event(EVENT_COMPLETED, 0, (uintptr_t)ws);
    }
    if (OT_PEERFLAG_D(peer_dest, peer_size) & PEER_FLAG_COMPLETED)
      OT_PEERFLAG(ws->peer) |= PEER_FLAG_COMPLETED;
  }

  memcpy(peer_dest, peer_src, peer_size);
#ifdef WANT_SYNC
  if (proto == FLAG_MCA) {
    mutex_bucket_unlock_by_hash(*ws->hash, delta_torrentcount);
    return 0;
  }
#endif

  ws->reply_size = return_peers_for_torrent(ws, torrent, amount, ws->reply, proto);
  mutex_bucket_unlock_by_hash(*ws->hash, delta_torrentcount);
  return ws->reply_size;
}

static size_t return_peers_all(ot_peerlist *peer_list, size_t peer_size, char *reply) {
  unsigned int bucket, num_buckets = 1;
  ot_vector   *bucket_list  = &peer_list->peers;
  size_t       compare_size = OT_PEER_COMPARE_SIZE_FROM_PEER_SIZE(peer_size);
  size_t       result       = compare_size * peer_list->peer_count;
  char        *r_end        = reply + result;

  if (OT_PEERLIST_HASBUCKETS(peer_list)) {
    num_buckets = bucket_list->size;
    bucket_list = (ot_vector *)bucket_list->data;
  }

  for (bucket = 0; bucket < num_buckets; ++bucket) {
    ot_peer *peers      = bucket_list[bucket].data;
    size_t   peer_count = bucket_list[bucket].size;
    while (peer_count--) {
      if (OT_PEERFLAG_D(peers, peer_size) & PEER_FLAG_SEEDING) {
        r_end -= compare_size;
        memcpy(r_end, peers, compare_size);
      } else {
        memcpy(reply, peers, compare_size);
        reply += compare_size;
      }
      peers += peer_size;
    }
  }
  return result;
}

static size_t return_peers_selection(struct ot_workstruct *ws, ot_peerlist *peer_list, size_t peer_size, size_t amount, char *reply) {
  unsigned int bucket_offset, bucket_index = 0, num_buckets = 1;
  ot_vector   *bucket_list  = &peer_list->peers;
  unsigned int shifted_pc   = peer_list->peer_count;
  unsigned int shifted_step = 0;
  unsigned int shift        = 0;
  size_t       compare_size = OT_PEER_COMPARE_SIZE_FROM_PEER_SIZE(peer_size);
  size_t       result       = compare_size * amount;
  char        *r_end        = reply + result;

  if (OT_PEERLIST_HASBUCKETS(peer_list)) {
    num_buckets = bucket_list->size;
    bucket_list = (ot_vector *)bucket_list->data;
  }

  /* Make fixpoint arithmetic as exact as possible */
#define MAXPRECBIT (1 << (8 * sizeof(int) - 3))
  while (!(shifted_pc & MAXPRECBIT)) {
    shifted_pc <<= 1;
    shift++;
  }
  shifted_step = shifted_pc / amount;
#undef MAXPRECBIT

  /* Initialize somewhere in the middle of peers so that
   fixpoint's aliasing doesn't alway miss the same peers */
  bucket_offset = nrand48(ws->rand48_state) % peer_list->peer_count;

  while (amount--) {
    ot_peer *peer;

    /* This is the aliased, non shifted range, next value may fall into */
    unsigned int diff  = (((amount + 1) * shifted_step) >> shift) - ((amount * shifted_step) >> shift);
    bucket_offset     += 1 + nrand48(ws->rand48_state) % diff;

    while (bucket_offset >= bucket_list[bucket_index].size) {
      bucket_offset -= bucket_list[bucket_index].size;
      bucket_index   = (bucket_index + 1) % num_buckets;
    }
    peer = bucket_list[bucket_index].data + peer_size * bucket_offset;
    if (OT_PEERFLAG_D(peer, peer_size) & PEER_FLAG_SEEDING) {
      r_end -= compare_size;
      memcpy(r_end, peer, compare_size);
    } else {
      memcpy(reply, peer, compare_size);
      reply += compare_size;
    }
  }
  return result;
}

static size_t return_peers_for_torrent_udp(struct ot_workstruct *ws, ot_torrent *torrent, size_t amount, char *reply) {
  char        *r          = reply;
  size_t       peer_size  = peer_size_from_peer6(&ws->peer);
  ot_peerlist *peer_list  = peer_size == OT_PEER_SIZE6 ? torrent->peer_list6 : torrent->peer_list4;
  size_t       peer_count = torrent->peer_list6->peer_count + torrent->peer_list4->peer_count;
  size_t       seed_count = torrent->peer_list6->seed_count + torrent->peer_list4->seed_count;

  if (amount > peer_list->peer_count)
    amount = peer_list->peer_count;

  *(uint32_t *)(r + 0)  = htonl(OT_CLIENT_REQUEST_INTERVAL_RANDOM);
  *(uint32_t *)(r + 4)  = htonl(peer_count - seed_count);
  *(uint32_t *)(r + 8)  = htonl(seed_count);
  r                    += 12;

  if (amount) {
    if (amount == peer_list->peer_count)
      r += return_peers_all(peer_list, peer_size, r);
    else
      r += return_peers_selection(ws, peer_list, peer_size, amount, r);
  }
  return r - reply;
}

static size_t return_peers_for_torrent_tcp(struct ot_workstruct *ws, ot_torrent *torrent, size_t amount, char *reply) {
  char  *r          = reply;
  int    erval      = OT_CLIENT_REQUEST_INTERVAL_RANDOM;
  size_t seed_count = torrent->peer_list6->seed_count + torrent->peer_list4->seed_count;
  size_t down_count = torrent->peer_list6->down_count + torrent->peer_list4->down_count;
  size_t peer_count = torrent->peer_list6->peer_count + torrent->peer_list4->peer_count - seed_count;

  /* Simple case: amount of peers in both lists is less than requested, here we return all results */
  size_t amount_v4  = torrent->peer_list4->peer_count;
  size_t amount_v6  = torrent->peer_list6->peer_count;

  /* Complex case: both lists have more than enough entries and we need to split between v4 and v6 clients */
  if (amount_v4 + amount_v6 > amount) {
    size_t       amount_left, percent_v6 = 0, percent_v4 = 0, left_v6, left_v4;
    const size_t SCALE = 1024;

    /* If possible, fill at least a quarter of peer from each family */
    if (amount / 4 <= amount_v4)
      amount_v4 = amount / 4;
    if (amount / 4 <= amount_v6)
      amount_v6 = amount / 4;

    /* Fill the rest according to which family's pool provides more peers */
    amount_left = amount - (amount_v4 + amount_v6);

    left_v4     = torrent->peer_list4->peer_count - amount_v4;
    left_v6     = torrent->peer_list6->peer_count - amount_v6;

    if (left_v4 + left_v6) {
      percent_v4 = (SCALE * left_v4) / (left_v4 + left_v6);
      percent_v6 = (SCALE * left_v6) / (left_v4 + left_v6);
    }

    amount_v4 += (amount_left * percent_v4) / SCALE;
    amount_v6 += (amount_left * percent_v6) / SCALE;

    /* Integer division rounding can leave out a peer */
    if (amount_v4 + amount_v6 < amount && amount_v6 < torrent->peer_list6->peer_count)
      ++amount_v6;
    if (amount_v4 + amount_v6 < amount && amount_v4 < torrent->peer_list4->peer_count)
      ++amount_v4;
  }

  r +=
      sprintf(r, "d8:completei%zde10:downloadedi%zde10:incompletei%zde8:intervali%ie12:min intervali%ie", seed_count, down_count, peer_count, erval, erval / 2);

  if (amount_v4) {
    r += sprintf(r, PEERS_BENCODED4 "%zd:", OT_PEER_COMPARE_SIZE4 * amount_v4);
    if (amount_v4 == torrent->peer_list4->peer_count)
      r += return_peers_all(torrent->peer_list4, OT_PEER_SIZE4, r);
    else
      r += return_peers_selection(ws, torrent->peer_list4, OT_PEER_SIZE4, amount_v4, r);
  }

  if (amount_v6) {
    r += sprintf(r, PEERS_BENCODED6 "%zd:", OT_PEER_COMPARE_SIZE6 * amount_v6);
    if (amount_v6 == torrent->peer_list6->peer_count)
      r += return_peers_all(torrent->peer_list6, OT_PEER_SIZE6, r);
    else
      r += return_peers_selection(ws, torrent->peer_list6, OT_PEER_SIZE6, amount_v6, r);
  }

  *r++ = 'e';

  return r - reply;
}

/* Compiles a list of random peers for a torrent
 * Reply must have enough space to hold:
 * 92 + 6 * amount bytes for TCP/IPv4
 * 92 + 18 * amount bytes for TCP/IPv6
 * 12 + 6 * amount bytes for UDP/IPv4
 * 12 + 18 * amount bytes for UDP/IPv6
 * Does not yet check not to return self
 */
size_t return_peers_for_torrent(struct ot_workstruct *ws, ot_torrent *torrent, size_t amount, char *reply, PROTO_FLAG proto) {
  return proto == FLAG_TCP ? return_peers_for_torrent_tcp(ws, torrent, amount, reply) : return_peers_for_torrent_udp(ws, torrent, amount, reply);
}

/* Fetches scrape info for a specific torrent */
size_t return_udp_scrape_for_torrent(ot_hash const hash, char *reply) {
  int         exactmatch, delta_torrentcount = 0;
  ot_vector  *torrents_list = mutex_bucket_lock_by_hash(hash);
  ot_torrent *torrent       = binary_search(hash, torrents_list->data, torrents_list->size, sizeof(ot_torrent), OT_HASH_COMPARE_SIZE, &exactmatch);

  if (!exactmatch) {
    memset(reply, 0, 12);
  } else {
    uint32_t *r = (uint32_t *)reply;

    if (clean_single_torrent(torrent)) {
      vector_remove_torrent(torrents_list, torrent);
      memset(reply, 0, 12);
      delta_torrentcount = -1;
    } else {
      r[0] = htonl(torrent->peer_list6->seed_count + torrent->peer_list4->seed_count);
      r[1] = htonl(torrent->peer_list6->down_count + torrent->peer_list4->down_count);
      r[2] = htonl(torrent->peer_list6->peer_count + torrent->peer_list4->peer_count - torrent->peer_list6->seed_count - torrent->peer_list4->seed_count);
    }
  }
  mutex_bucket_unlock_by_hash(hash, delta_torrentcount);
  return 12;
}

/* Fetches scrape info for a specific torrent */
size_t return_tcp_scrape_for_torrent(ot_hash const *hash_list, int amount, char *reply) {
  char *r = reply;
  int   exactmatch, i;

  r += sprintf(r, "d5:filesd");

  for (i = 0; i < amount; ++i) {
    int            delta_torrentcount = 0;
    ot_hash const *hash               = hash_list + i;
    ot_vector     *torrents_list      = mutex_bucket_lock_by_hash(*hash);
    ot_torrent    *torrent            = binary_search(hash, torrents_list->data, torrents_list->size, sizeof(ot_torrent), OT_HASH_COMPARE_SIZE, &exactmatch);

    if (exactmatch) {
      if (clean_single_torrent(torrent)) {
        vector_remove_torrent(torrents_list, torrent);
        delta_torrentcount = -1;
      } else {
        *r++ = '2';
        *r++ = '0';
        *r++ = ':';
        memcpy(r, hash, sizeof(ot_hash));
        r += sizeof(ot_hash);
        r += sprintf(r, "d8:completei%zde10:downloadedi%zde10:incompletei%zdee", torrent->peer_list6->seed_count + torrent->peer_list4->seed_count,
                     torrent->peer_list6->down_count + torrent->peer_list4->down_count,
                     torrent->peer_list6->peer_count + torrent->peer_list4->peer_count - torrent->peer_list6->seed_count - torrent->peer_list4->seed_count);
      }
    }
    mutex_bucket_unlock_by_hash(*hash, delta_torrentcount);
  }

  *r++ = 'e';
  *r++ = 'e';
  return r - reply;
}

static ot_peerlist dummy_list;
size_t remove_peer_from_torrent(PROTO_FLAG proto, struct ot_workstruct *ws) {
  int            exactmatch;
  ot_vector     *torrents_list = mutex_bucket_lock_by_hash(*ws->hash);
  ot_torrent    *torrent = binary_search(ws->hash, torrents_list->data, torrents_list->size, sizeof(ot_torrent), OT_HASH_COMPARE_SIZE, &exactmatch);
  ot_peerlist   *peer_list = &dummy_list;
  size_t         peer_size; /* initialized in next line */
  ot_peer const *peer_src   = peer_from_peer6(&ws->peer, &peer_size);
  size_t         peer_count = 0, seed_count = 0;

#ifdef WANT_SYNC_LIVE
  if (proto != FLAG_MCA) {
    OT_PEERFLAG(ws->peer) |= PEER_FLAG_STOPPED;
    livesync_tell(ws);
  }
#endif

  if (exactmatch) {
    peer_list = peer_size == OT_PEER_SIZE6 ? torrent->peer_list6 : torrent->peer_list4;
    switch (vector_remove_peer(&peer_list->peers, peer_src, peer_size)) {
    case 2:
      peer_list->seed_count--; /* Intentional fallthrough */
    case 1:
      peer_list->peer_count--; /* Intentional fallthrough */
    default:
      break;
    }

    peer_count = torrent->peer_list6->peer_count + torrent->peer_list4->peer_count;
    seed_count = torrent->peer_list6->seed_count + torrent->peer_list4->seed_count;
  }

  if (proto == FLAG_TCP) {
    int erval      = OT_CLIENT_REQUEST_INTERVAL_RANDOM;
    ws->reply_size = sprintf(ws->reply, "d8:completei%zde10:incompletei%zde8:intervali%ie12:min intervali%ie%s0:e", seed_count, peer_count - seed_count, erval,
                             erval / 2, peer_size == OT_PEER_SIZE6 ? PEERS_BENCODED6 : PEERS_BENCODED4);
  }

  /* Handle UDP reply */
  if (proto == FLAG_UDP) {
    ((uint32_t *)ws->reply)[2] = htonl(OT_CLIENT_REQUEST_INTERVAL_RANDOM);
    ((uint32_t *)ws->reply)[3] = htonl(peer_count - seed_count);
    ((uint32_t *)ws->reply)[4] = htonl(seed_count);
    ws->reply_size             = 20;
  }

  mutex_bucket_unlock_by_hash(*ws->hash, 0);
  return ws->reply_size;
}

void iterate_all_torrents(int (*for_each)(ot_torrent *torrent, uintptr_t data), uintptr_t data) {
  int    bucket;
  size_t j;

  for (bucket = 0; bucket < OT_BUCKET_COUNT; ++bucket) {
    ot_vector  *torrents_list = mutex_bucket_lock(bucket);
    ot_torrent *torrents      = (ot_torrent *)(torrents_list->data);

    for (j = 0; j < torrents_list->size; ++j)
      if (for_each(torrents + j, data))
        break;

    mutex_bucket_unlock(bucket, 0);
    if (!g_opentracker_running)
      return;
  }
}

ot_peer *peer_from_peer6(ot_peer6 *peer, size_t *peer_size) {
  ot_ip6 *ip = (ot_ip6 *)peer;
  if (!ip6_isv4mapped(ip)) {
    *peer_size = OT_PEER_SIZE6;
    return (ot_peer *)peer;
  }
  *peer_size = OT_PEER_SIZE4;
  return (ot_peer *)(((uint8_t *)peer) + 12);
}

size_t peer_size_from_peer6(ot_peer6 *peer) {
  ot_ip6 *ip = (ot_ip6 *)peer;
  if (!ip6_isv4mapped(ip))
    return OT_PEER_SIZE6;
  return OT_PEER_SIZE4;
}

#ifdef _DEBUG_RANDOMTORRENTS
void trackerlogic_add_random_torrents(size_t amount) {
  struct ot_workstruct ws;
  memset(&ws, 0, sizeof(ws));

  ws.inbuf  = malloc(G_INBUF_SIZE);
  ws.outbuf = malloc(G_OUTBUF_SIZE);
  ws.reply  = ws.outbuf;
  ws.hash   = (ot_hash *)ws.inbuf;

  while (amount--) {
    arc4random_buf(ws.hash, sizeof(ot_hash));
    arc4random_buf(&ws.peer, sizeof(ws.peer));

    OT_PEERFLAG(ws.peer) &= PEER_FLAG_SEEDING | PEER_FLAG_COMPLETED | PEER_FLAG_STOPPED;

    add_peer_to_torrent_and_return_peers(FLAG_TCP, &ws, 1);
  }

  free(ws.inbuf);
  free(ws.outbuf);
}
#endif

void exerr(char *message) {
  fprintf(stderr, "%s\n", message);
  exit(111);
}

void trackerlogic_init() {
  g_tracker_id = random();

  if (!g_stats_path)
    g_stats_path = "stats";
  g_stats_path_len = strlen(g_stats_path);

  /* Initialise background worker threads */
  mutex_init();
  clean_init();
  fullscrape_init();
  accesslist_init();
  livesync_init();
  stats_init();
}

void trackerlogic_deinit(void) {
  int    bucket, delta_torrentcount = 0;
  size_t j;

  /* Free all torrents... */
  for (bucket = 0; bucket < OT_BUCKET_COUNT; ++bucket) {
    ot_vector *torrents_list = mutex_bucket_lock(bucket);
    if (torrents_list->size) {
      for (j = 0; j < torrents_list->size; ++j) {
        ot_torrent *torrent = ((ot_torrent *)(torrents_list->data)) + j;
        free_peerlist(torrent->peer_list6);
        free_peerlist(torrent->peer_list4);
        delta_torrentcount -= 1;
      }
      free(torrents_list->data);
    }
    mutex_bucket_unlock(bucket, delta_torrentcount);
  }

  /* Deinitialise background worker threads */
  stats_deinit();
  livesync_deinit();
  accesslist_deinit();
  fullscrape_deinit();
  clean_deinit();
  /* Release mutexes */
  mutex_deinit();
}