transmission/libtransmission/announcer.cc

1816 lines
53 KiB
C++

// This file Copyright © 2010-2022 Mnemosyne LLC.
// It may be used under GPLv2 (SPDX: GPL-2.0), GPLv3 (SPDX: GPL-3.0),
// or any future license endorsed by Mnemosyne LLC.
// License text can be found in the licenses/ folder.
#include <algorithm>
#include <array>
#include <climits> /* INT_MAX */
#include <cstdio>
#include <cstring>
#include <ctime>
#include <map>
#include <set>
#include <string>
#include <string_view>
#include <vector>
#include <event2/buffer.h>
#include <event2/event.h> /* evtimer */
#define LIBTRANSMISSION_ANNOUNCER_MODULE
#include "transmission.h"
#include "announce-list.h"
#include "announcer-common.h"
#include "announcer.h"
#include "crypto-utils.h" /* tr_rand_int(), tr_rand_int_weak() */
#include "log.h"
#include "peer-mgr.h" /* tr_peerMgrCompactToPex() */
#include "session.h"
#include "torrent.h"
#include "tr-assert.h"
#include "utils.h"
#include "web-utils.h"
using namespace std::literals;
struct tr_tier;
static void tier_build_log_name(struct tr_tier const* tier, char* buf, size_t buflen);
#define dbgmsg(tier, ...) \
do \
{ \
if (tr_logGetDeepEnabled()) \
{ \
char name[128]; \
tier_build_log_name(tier, name, TR_N_ELEMENTS(name)); \
tr_logAddDeep(__FILE__, __LINE__, name, __VA_ARGS__); \
} \
} while (0)
/* unless the tracker says otherwise, rescrape this frequently */
static auto constexpr DefaultScrapeIntervalSec = int{ 60 * 30 };
/* unless the tracker says otherwise, this is the announce interval */
static auto constexpr DefaultAnnounceIntervalSec = int{ 60 * 10 };
/* unless the tracker says otherwise, this is the announce min_interval */
static auto constexpr DefaultAnnounceMinIntervalSec = int{ 60 * 2 };
/* the value of the 'numwant' argument passed in tracker requests. */
static auto constexpr Numwant = int{ 80 };
/* how often to announce & scrape */
static auto constexpr UpkeepIntervalMsec = int{ 500 };
static auto constexpr MaxAnnouncesPerUpkeep = int{ 20 };
static auto constexpr MaxScrapesPerUpkeep = int{ 20 };
/* this is how often to call the UDP tracker upkeep */
static auto constexpr TauUpkeepIntervalSecs = int{ 5 };
/* how many infohashes to remove when we get a scrape-too-long error */
static auto constexpr TrMultiscrapeStep = int{ 5 };
/***
****
***/
char const* tr_announce_event_get_string(tr_announce_event e)
{
switch (e)
{
case TR_ANNOUNCE_EVENT_COMPLETED:
return "completed";
case TR_ANNOUNCE_EVENT_STARTED:
return "started";
case TR_ANNOUNCE_EVENT_STOPPED:
return "stopped";
default:
return "";
}
}
namespace
{
struct StopsCompare
{
int compare(tr_announce_request const* a, tr_announce_request const* b) const // <=>
{
// primary key: volume of data transferred
auto const ax = a->up + a->down;
auto const bx = b->up + b->down;
if (ax < bx)
{
return -1;
}
if (ax > bx)
{
return 1;
}
// secondary key: the torrent's info_hash
if (a->info_hash < b->info_hash)
{
return -1;
}
if (a->info_hash > b->info_hash)
{
return 1;
}
// tertiary key: the tracker's announce url
if (a->announce_url < b->announce_url)
{
return -1;
}
if (a->announce_url > b->announce_url)
{
return 1;
}
return 0;
}
bool operator()(tr_announce_request const* a, tr_announce_request const* b) const // less than
{
return compare(a, b) < 0;
}
};
} // namespace
/***
****
***/
struct tr_scrape_info
{
tr_interned_string scrape_url;
int multiscrape_max;
tr_scrape_info(tr_interned_string scrape_url_in, int const multiscrape_max_in)
: scrape_url{ scrape_url_in }
, multiscrape_max{ multiscrape_max_in }
{
}
};
/**
* "global" (per-tr_session) fields
*/
struct tr_announcer
{
std::set<tr_announce_request*, StopsCompare> stops;
std::map<tr_interned_string, tr_scrape_info> scrape_info;
tr_session* session;
struct event* upkeepTimer;
int key;
time_t tauUpkeepAt;
};
static tr_scrape_info* tr_announcerGetScrapeInfo(tr_announcer* announcer, tr_interned_string url)
{
if (std::empty(url))
{
return nullptr;
}
auto& scrapes = announcer->scrape_info;
auto const it = scrapes.try_emplace(url, url, TR_MULTISCRAPE_MAX);
return &it.first->second;
}
static void onUpkeepTimer(evutil_socket_t fd, short what, void* vannouncer);
void tr_announcerInit(tr_session* session)
{
TR_ASSERT(tr_isSession(session));
auto* a = new tr_announcer{};
a->key = tr_rand_int(INT_MAX);
a->session = session;
a->upkeepTimer = evtimer_new(session->event_base, onUpkeepTimer, a);
tr_timerAddMsec(a->upkeepTimer, UpkeepIntervalMsec);
session->announcer = a;
}
static void flushCloseMessages(tr_announcer* announcer);
void tr_announcerClose(tr_session* session)
{
tr_announcer* announcer = session->announcer;
flushCloseMessages(announcer);
tr_tracker_udp_start_shutdown(session);
event_free(announcer->upkeepTimer);
announcer->upkeepTimer = nullptr;
session->announcer = nullptr;
delete announcer;
}
/***
****
***/
/* a row in tr_tier's list of trackers */
struct tr_tracker
{
tr_interned_string key;
tr_interned_string announce_url;
struct tr_scrape_info* scrape_info;
char* tracker_id_str;
int seederCount;
int leecherCount;
int downloadCount;
int downloaderCount;
int consecutiveFailures;
uint32_t id;
};
// format: `${host}:${port}`
tr_interned_string tr_announcerGetKey(tr_url_parsed_t const& parsed)
{
std::string buf;
tr_buildBuf(buf, parsed.host, ":"sv, parsed.portstr);
return tr_interned_string{ buf };
}
static void trackerConstruct(tr_announcer* announcer, tr_tracker* tracker, tr_announce_list::tracker_info const& info)
{
memset(tracker, 0, sizeof(tr_tracker));
tracker->key = info.host;
tracker->announce_url = info.announce_str;
tracker->scrape_info = std::empty(info.scrape_str) ? nullptr : tr_announcerGetScrapeInfo(announcer, info.scrape_str);
tracker->id = info.id;
tracker->seederCount = -1;
tracker->leecherCount = -1;
tracker->downloadCount = -1;
}
static void trackerDestruct(tr_tracker* tracker)
{
tr_free(tracker->tracker_id_str);
}
/***
****
***/
struct tr_announcer_tiers;
/** @brief A group of trackers in a single tier, as per the multitracker spec */
struct tr_tier
{
/* number of up/down/corrupt bytes since the last time we sent an
* "event=stopped" message that was acknowledged by the tracker */
uint64_t byteCounts[3];
tr_tracker* trackers;
int tracker_count;
tr_tracker* currentTracker;
int currentTrackerIndex;
tr_torrent* tor;
time_t scrapeAt;
time_t lastScrapeStartTime;
time_t lastScrapeTime;
bool lastScrapeSucceeded;
bool lastScrapeTimedOut;
time_t announceAt;
time_t manualAnnounceAllowedAt;
time_t lastAnnounceStartTime;
time_t lastAnnounceTime;
bool lastAnnounceSucceeded;
bool lastAnnounceTimedOut;
tr_announce_event* announce_events;
int announce_event_priority;
int announce_event_count;
int announce_event_alloc;
/* unique lookup key */
int key;
int scrapeIntervalSec;
int announceIntervalSec;
int announceMinIntervalSec;
int lastAnnouncePeerCount;
bool isRunning;
bool isAnnouncing;
bool isScraping;
bool wasCopied;
char lastAnnounceStr[128];
char lastScrapeStr[128];
};
static time_t get_next_scrape_time(tr_session const* session, tr_tier const* tier, int interval)
{
/* Maybe don't scrape paused torrents */
if (!tier->isRunning && !session->scrapePausedTorrents)
{
return 0;
}
/* Add the interval, and then increment to the nearest 10th second.
* The latter step is to increase the odds of several torrents coming
* due at the same time to improve multiscrape. */
time_t const now = tr_time();
time_t ret = now + interval;
while (ret % 10 != 0)
{
++ret;
}
return ret;
}
static void tierConstruct(tr_tier* tier, tr_torrent* tor)
{
static int nextKey = 1;
memset(tier, 0, sizeof(tr_tier));
tier->key = nextKey++;
tier->currentTrackerIndex = -1;
tier->scrapeIntervalSec = DefaultScrapeIntervalSec;
tier->announceIntervalSec = DefaultAnnounceIntervalSec;
tier->announceMinIntervalSec = DefaultAnnounceMinIntervalSec;
tier->scrapeAt = get_next_scrape_time(tor->session, tier, 0);
tier->tor = tor;
}
static void tierDestruct(tr_tier* tier)
{
tr_free(tier->announce_events);
}
static void tier_build_log_name(tr_tier const* tier, char* buf, size_t buflen)
{
auto const* const name = tier != nullptr && tier->tor != nullptr ? tr_torrentName(tier->tor) : "?";
auto const key_sv = tier != nullptr && tier->currentTracker != nullptr ? tier->currentTracker->key.sv() : "?"sv;
tr_snprintf(buf, buflen, "[%s---%" TR_PRIsv "]", name, TR_PRIsv_ARG(key_sv));
}
static void tierIncrementTracker(tr_tier* tier)
{
/* move our index to the next tracker in the tier */
int const i = tier->currentTracker == nullptr ? 0 : (tier->currentTrackerIndex + 1) % tier->tracker_count;
tier->currentTrackerIndex = i;
tier->currentTracker = &tier->trackers[i];
/* reset some of the tier's fields */
tier->scrapeIntervalSec = DefaultScrapeIntervalSec;
tier->announceIntervalSec = DefaultAnnounceIntervalSec;
tier->announceMinIntervalSec = DefaultAnnounceMinIntervalSec;
tier->isAnnouncing = false;
tier->isScraping = false;
tier->lastAnnounceStartTime = 0;
tier->lastScrapeStartTime = 0;
}
/***
****
***/
/**
* @brief Opaque, per-torrent data structure for tracker announce information
*
* this opaque data structure can be found in tr_torrent.tiers
*/
struct tr_announcer_tiers
{
tr_tier* tiers;
int tier_count;
tr_tracker* trackers;
int tracker_count;
tr_tracker_callback callback;
void* callbackData;
};
static tr_announcer_tiers* tiersNew(void)
{
return tr_new0(tr_announcer_tiers, 1);
}
static void tiersDestruct(tr_announcer_tiers* tt)
{
for (int i = 0; i < tt->tracker_count; ++i)
{
trackerDestruct(&tt->trackers[i]);
}
tr_free(tt->trackers);
for (int i = 0; i < tt->tier_count; ++i)
{
tierDestruct(&tt->tiers[i]);
}
tr_free(tt->tiers);
}
static void tiersFree(tr_announcer_tiers* tt)
{
tiersDestruct(tt);
tr_free(tt);
}
static tr_tier* getTier(tr_announcer* announcer, tr_sha1_digest_t const& info_hash, int tierId)
{
tr_tier* tier = nullptr;
if (announcer != nullptr)
{
tr_torrent* const tor = announcer->session->getTorrent(info_hash);
if (tor != nullptr && tor->announcer_tiers != nullptr)
{
tr_announcer_tiers* tt = tor->announcer_tiers;
for (int i = 0; tier == nullptr && i < tt->tier_count; ++i)
{
if (tt->tiers[i].key == tierId)
{
tier = &tt->tiers[i];
}
}
}
}
return tier;
}
/***
**** PUBLISH
***/
static void publishMessage(tr_tier* tier, std::string_view msg, TrackerEventType type)
{
if (tier != nullptr && tier->tor != nullptr && tier->tor->announcer_tiers != nullptr &&
tier->tor->announcer_tiers->callback != nullptr)
{
tr_announcer_tiers* tiers = tier->tor->announcer_tiers;
auto event = tr_tracker_event{};
event.messageType = type;
event.text = msg;
if (tier->currentTracker != nullptr)
{
event.announce_url = tier->currentTracker->announce_url;
}
(*tiers->callback)(tier->tor, &event, tiers->callbackData);
}
}
static void publishErrorClear(tr_tier* tier)
{
publishMessage(tier, ""sv, TR_TRACKER_ERROR_CLEAR);
}
static void publishWarning(tr_tier* tier, std::string_view msg)
{
publishMessage(tier, msg, TR_TRACKER_WARNING);
}
static void publishError(tr_tier* tier, std::string_view msg)
{
publishMessage(tier, msg, TR_TRACKER_ERROR);
}
static void publishPeerCounts(tr_tier* tier, int seeders, int leechers)
{
if (tier->tor->announcer_tiers->callback != nullptr)
{
auto e = tr_tracker_event{};
e.messageType = TR_TRACKER_COUNTS;
e.seeders = seeders;
e.leechers = leechers;
dbgmsg(tier, "peer counts: %d seeders, %d leechers.", seeders, leechers);
(*tier->tor->announcer_tiers->callback)(tier->tor, &e, nullptr);
}
}
static void publishPeersPex(tr_tier* tier, int seeders, int leechers, tr_pex const* pex, int n)
{
if (tier->tor->announcer_tiers->callback != nullptr)
{
auto e = tr_tracker_event{};
e.messageType = TR_TRACKER_PEERS;
e.seeders = seeders;
e.leechers = leechers;
e.pex = pex;
e.pexCount = n;
dbgmsg(tier, "tracker knows of %d seeders and %d leechers and gave a list of %d peers.", seeders, leechers, n);
(*tier->tor->announcer_tiers->callback)(tier->tor, &e, nullptr);
}
}
/***
****
***/
static void addTorrentToTier(tr_announcer_tiers* tt, tr_torrent* tor)
{
auto const n = tor->trackerCount();
auto const tiers = tor->tiers();
// build the tracker and tier arrays
tt->trackers = tr_new0(tr_tracker, n);
tt->tracker_count = n;
tt->tiers = tr_new0(tr_tier, std::size(tiers));
auto prev_tier = std::optional<tr_tracker_tier_t>{};
tr_tier* tier = nullptr;
for (size_t i = 0; i < n; ++i)
{
auto const info = tor->tracker(i);
trackerConstruct(tor->session->announcer, &tt->trackers[i], info);
if (!prev_tier || *prev_tier != info.tier)
{
tier = &tt->tiers[tt->tier_count++];
tierConstruct(tier, tor);
tier->trackers = &tt->trackers[i];
tier->tracker_count = 1;
tierIncrementTracker(tier);
prev_tier = info.tier;
}
else
{
++tier->tracker_count;
}
}
}
tr_announcer_tiers* tr_announcerAddTorrent(tr_torrent* tor, tr_tracker_callback callback, void* callbackData)
{
TR_ASSERT(tr_isTorrent(tor));
tr_announcer_tiers* tiers = tiersNew();
tiers->callback = callback;
tiers->callbackData = callbackData;
addTorrentToTier(tiers, tor);
return tiers;
}
/***
****
***/
static bool tierCanManualAnnounce(tr_tier const* tier)
{
return tier->manualAnnounceAllowedAt <= tr_time();
}
bool tr_announcerCanManualAnnounce(tr_torrent const* tor)
{
TR_ASSERT(tr_isTorrent(tor));
TR_ASSERT(tor->announcer_tiers != nullptr);
struct tr_announcer_tiers const* tt = nullptr;
if (tor->isRunning)
{
tt = tor->announcer_tiers;
}
/* return true if any tier can manual announce */
for (int i = 0; tt != nullptr && i < tt->tier_count; ++i)
{
if (tierCanManualAnnounce(&tt->tiers[i]))
{
return true;
}
}
return false;
}
time_t tr_announcerNextManualAnnounce(tr_torrent const* tor)
{
time_t ret = ~(time_t)0;
struct tr_announcer_tiers const* tt = tor->announcer_tiers;
/* find the earliest manual announce time from all peers */
for (int i = 0; tt != nullptr && i < tt->tier_count; ++i)
{
if (tt->tiers[i].isRunning)
{
ret = std::min(ret, tt->tiers[i].manualAnnounceAllowedAt);
}
}
return ret;
}
static void dbgmsg_tier_announce_queue(tr_tier const* tier)
{
if (tr_logGetDeepEnabled())
{
char name[128];
struct evbuffer* buf = evbuffer_new();
tier_build_log_name(tier, name, sizeof(name));
for (int i = 0; i < tier->announce_event_count; ++i)
{
tr_announce_event const e = tier->announce_events[i];
char const* str = tr_announce_event_get_string(e);
evbuffer_add_printf(buf, "[%d:%s]", i, str);
}
auto const message = evbuffer_free_to_str(buf);
tr_logAddDeep(__FILE__, __LINE__, name, "announce queue is %" TR_PRIsv, TR_PRIsv_ARG(message));
}
}
// higher priorities go to the front of the announce queue
static void tier_update_announce_priority(tr_tier* tier)
{
int priority = -1;
for (int i = 0; i < tier->announce_event_count; ++i)
{
priority = std::max(priority, int{ tier->announce_events[i] });
}
tier->announce_event_priority = priority;
}
static void tier_announce_remove_trailing(tr_tier* tier, tr_announce_event e)
{
while (tier->announce_event_count > 0 && tier->announce_events[tier->announce_event_count - 1] == e)
{
--tier->announce_event_count;
}
tier_update_announce_priority(tier);
}
static void tier_announce_event_push(tr_tier* tier, tr_announce_event e, time_t announceAt)
{
TR_ASSERT(tier != nullptr);
dbgmsg_tier_announce_queue(tier);
dbgmsg(tier, "queued \"%s\"", tr_announce_event_get_string(e));
if (tier->announce_event_count > 0)
{
/* special case #1: if we're adding a "stopped" event,
* dump everything leading up to it except "completed" */
if (e == TR_ANNOUNCE_EVENT_STOPPED)
{
bool has_completed = false;
tr_announce_event const c = TR_ANNOUNCE_EVENT_COMPLETED;
for (int i = 0; !has_completed && i < tier->announce_event_count; ++i)
{
has_completed = c == tier->announce_events[i];
}
tier->announce_event_count = 0;
if (has_completed)
{
tier->announce_events[tier->announce_event_count++] = c;
tier_update_announce_priority(tier);
}
}
/* special case #2: dump all empty strings leading up to this event */
tier_announce_remove_trailing(tier, TR_ANNOUNCE_EVENT_NONE);
/* special case #3: no consecutive duplicates */
tier_announce_remove_trailing(tier, e);
}
/* make room in the array for another event */
if (tier->announce_event_alloc <= tier->announce_event_count)
{
tier->announce_event_alloc += 4;
tier->announce_events = tr_renew(tr_announce_event, tier->announce_events, tier->announce_event_alloc);
}
/* add it */
tier->announceAt = announceAt;
tier->announce_events[tier->announce_event_count++] = e;
tier_update_announce_priority(tier);
dbgmsg_tier_announce_queue(tier);
dbgmsg(tier, "announcing in %d seconds", (int)difftime(announceAt, tr_time()));
}
static tr_announce_event tier_announce_event_pull(tr_tier* tier)
{
tr_announce_event const e = tier->announce_events[0];
tr_removeElementFromArray(tier->announce_events, 0, sizeof(tr_announce_event), tier->announce_event_count);
--tier->announce_event_count;
tier_update_announce_priority(tier);
return e;
}
static void torrentAddAnnounce(tr_torrent* tor, tr_announce_event e, time_t announceAt)
{
struct tr_announcer_tiers* tt = tor->announcer_tiers;
/* walk through each tier and tell them to announce */
for (int i = 0; i < tt->tier_count; ++i)
{
tier_announce_event_push(&tt->tiers[i], e, announceAt);
}
}
void tr_announcerTorrentStarted(tr_torrent* tor)
{
torrentAddAnnounce(tor, TR_ANNOUNCE_EVENT_STARTED, tr_time());
}
void tr_announcerManualAnnounce(tr_torrent* tor)
{
torrentAddAnnounce(tor, TR_ANNOUNCE_EVENT_NONE, tr_time());
}
void tr_announcerTorrentStopped(tr_torrent* tor)
{
torrentAddAnnounce(tor, TR_ANNOUNCE_EVENT_STOPPED, tr_time());
}
void tr_announcerTorrentCompleted(tr_torrent* tor)
{
torrentAddAnnounce(tor, TR_ANNOUNCE_EVENT_COMPLETED, tr_time());
}
void tr_announcerChangeMyPort(tr_torrent* tor)
{
tr_announcerTorrentStarted(tor);
}
/***
****
***/
void tr_announcerAddBytes(tr_torrent* tor, int type, uint32_t byteCount)
{
TR_ASSERT(tr_isTorrent(tor));
TR_ASSERT(type == TR_ANN_UP || type == TR_ANN_DOWN || type == TR_ANN_CORRUPT);
struct tr_announcer_tiers* tt = tor->announcer_tiers;
for (int i = 0; i < tt->tier_count; ++i)
{
tt->tiers[i].byteCounts[type] += byteCount;
}
}
/***
****
***/
static tr_announce_request* announce_request_new(
tr_announcer const* announcer,
tr_torrent* tor,
tr_tier const* tier,
tr_announce_event event)
{
auto* const req = tr_new0(tr_announce_request, 1);
req->port = tr_sessionGetPublicPeerPort(announcer->session);
req->announce_url = tier->currentTracker->announce_url;
req->tracker_id_str = tr_strdup(tier->currentTracker->tracker_id_str);
req->info_hash = tor->infoHash();
req->peer_id = tr_torrentGetPeerId(tor);
req->up = tier->byteCounts[TR_ANN_UP];
req->down = tier->byteCounts[TR_ANN_DOWN];
req->corrupt = tier->byteCounts[TR_ANN_CORRUPT];
req->leftUntilComplete = tor->hasMetadata() ? tor->totalSize() - tor->hasTotal() : INT64_MAX;
req->event = event;
req->numwant = event == TR_ANNOUNCE_EVENT_STOPPED ? 0 : Numwant;
req->key = announcer->key;
req->partial_seed = tor->isPartialSeed();
tier_build_log_name(tier, req->log_name, sizeof(req->log_name));
return req;
}
static void announce_request_free(tr_announce_request* req);
void tr_announcerRemoveTorrent(tr_announcer* announcer, tr_torrent* tor)
{
struct tr_announcer_tiers const* tt = tor->announcer_tiers;
if (tt != nullptr)
{
for (int i = 0; i < tt->tier_count; ++i)
{
tr_tier const* tier = &tt->tiers[i];
if (tier->isRunning)
{
tr_announce_event const e = TR_ANNOUNCE_EVENT_STOPPED;
tr_announce_request* req = announce_request_new(announcer, tor, tier, e);
if (announcer->stops.count(req))
{
announce_request_free(req);
}
else
{
announcer->stops.insert(req);
}
}
}
tiersFree(tor->announcer_tiers);
tor->announcer_tiers = nullptr;
}
}
static int getRetryInterval(tr_tracker const* t)
{
switch (t->consecutiveFailures)
{
case 0:
return 0;
case 1:
return 20;
case 2:
return tr_rand_int_weak(60) + 60 * 5;
case 3:
return tr_rand_int_weak(60) + 60 * 15;
case 4:
return tr_rand_int_weak(60) + 60 * 30;
case 5:
return tr_rand_int_weak(60) + 60 * 60;
default:
return tr_rand_int_weak(60) + 60 * 120;
}
}
struct announce_data
{
int tierId;
time_t timeSent;
tr_announce_event event;
tr_session* session;
/** If the request succeeds, the value for tier's "isRunning" flag */
bool isRunningOnSuccess;
};
static void on_announce_error(tr_tier* tier, char const* err, tr_announce_event e)
{
/* increment the error count */
if (tier->currentTracker != nullptr)
{
++tier->currentTracker->consecutiveFailures;
}
/* set the error message */
tr_strlcpy(tier->lastAnnounceStr, err, sizeof(tier->lastAnnounceStr));
/* switch to the next tracker */
tierIncrementTracker(tier);
/* schedule a reannounce */
int const interval = getRetryInterval(tier->currentTracker);
auto const* const key_cstr = tier->currentTracker->key.c_str();
dbgmsg(tier, "Tracker '%s' announce error: %s (Retrying in %d seconds)", key_cstr, err, interval);
tr_logAddTorInfo(tier->tor, "Tracker '%s' announce error: %s (Retrying in %d seconds)", key_cstr, err, interval);
tier_announce_event_push(tier, e, tr_time() + interval);
}
static void on_announce_done(tr_announce_response const* response, void* vdata)
{
auto* data = static_cast<struct announce_data*>(vdata);
tr_announcer* announcer = data->session->announcer;
tr_tier* tier = getTier(announcer, response->info_hash, data->tierId);
time_t const now = tr_time();
tr_announce_event const event = data->event;
if (tier != nullptr)
{
dbgmsg(
tier,
"Got announce response: "
"connected:%d "
"timeout:%d "
"seeders:%d "
"leechers:%d "
"downloads:%d "
"interval:%d "
"min_interval:%d "
"tracker_id_str:%s "
"pex:%zu "
"pex6:%zu "
"err:%s "
"warn:%s",
(int)response->did_connect,
(int)response->did_timeout,
response->seeders,
response->leechers,
response->downloads,
response->interval,
response->min_interval,
response->tracker_id_str != nullptr ? response->tracker_id_str : "none",
response->pex_count,
response->pex6_count,
(!std::empty(response->errmsg) ? response->errmsg.c_str() : "none"),
(!std::empty(response->warning) ? response->warning.c_str() : "none"));
tier->lastAnnounceTime = now;
tier->lastAnnounceTimedOut = response->did_timeout;
tier->lastAnnounceSucceeded = false;
tier->isAnnouncing = false;
tier->manualAnnounceAllowedAt = now + tier->announceMinIntervalSec;
if (!response->did_connect)
{
on_announce_error(tier, _("Could not connect to tracker"), event);
}
else if (response->did_timeout)
{
on_announce_error(tier, _("Tracker did not respond"), event);
}
else if (!std::empty(response->errmsg))
{
/* If the torrent's only tracker returned an error, publish it.
Don't bother publishing if there are other trackers -- it's
all too common for people to load up dozens of dead trackers
in a torrent's metainfo... */
if (tier->tor->trackerCount() < 2)
{
publishError(tier, response->errmsg);
}
on_announce_error(tier, response->errmsg.c_str(), event);
}
else
{
auto const isStopped = event == TR_ANNOUNCE_EVENT_STOPPED;
auto leechers = int{};
auto scrape_fields = int{};
auto seeders = int{};
publishErrorClear(tier);
tr_tracker* const tracker = tier->currentTracker;
if (tracker != nullptr)
{
tracker->consecutiveFailures = 0;
if (response->seeders >= 0)
{
tracker->seederCount = seeders = response->seeders;
++scrape_fields;
}
if (response->leechers >= 0)
{
tracker->leecherCount = leechers = response->leechers;
++scrape_fields;
}
if (response->downloads >= 0)
{
tracker->downloadCount = response->downloads;
++scrape_fields;
}
if (response->tracker_id_str != nullptr)
{
tr_free(tracker->tracker_id_str);
tracker->tracker_id_str = tr_strdup(response->tracker_id_str);
}
}
if (auto const& warning = response->warning; !std::empty(warning))
{
tr_strlcpy(tier->lastAnnounceStr, warning.c_str(), sizeof(tier->lastAnnounceStr));
dbgmsg(tier, "tracker gave \"%s\"", warning.c_str());
publishWarning(tier, warning);
}
else
{
tr_strlcpy(tier->lastAnnounceStr, _("Success"), sizeof(tier->lastAnnounceStr));
}
if (response->min_interval != 0)
{
tier->announceMinIntervalSec = response->min_interval;
}
if (response->interval != 0)
{
tier->announceIntervalSec = response->interval;
}
if (response->pex_count > 0)
{
publishPeersPex(tier, seeders, leechers, response->pex, response->pex_count);
}
if (response->pex6_count > 0)
{
publishPeersPex(tier, seeders, leechers, response->pex6, response->pex6_count);
}
publishPeerCounts(tier, seeders, leechers);
tier->isRunning = data->isRunningOnSuccess;
/* if the tracker included scrape fields in its announce response,
then a separate scrape isn't needed */
if (scrape_fields >= 3 || (scrape_fields >= 1 && tracker->scrape_info == nullptr))
{
tr_logAddTorDbg(
tier->tor,
"Announce response contained scrape info; "
"rescheduling next scrape to %d seconds from now.",
tier->scrapeIntervalSec);
tier->scrapeAt = get_next_scrape_time(announcer->session, tier, tier->scrapeIntervalSec);
tier->lastScrapeTime = now;
tier->lastScrapeSucceeded = true;
}
else if (tier->lastScrapeTime + tier->scrapeIntervalSec <= now)
{
tier->scrapeAt = get_next_scrape_time(announcer->session, tier, 0);
}
tier->lastAnnounceSucceeded = true;
tier->lastAnnouncePeerCount = response->pex_count + response->pex6_count;
if (isStopped)
{
/* now that we've successfully stopped the torrent,
* we can reset the up/down/corrupt count we've kept
* for this tracker */
tier->byteCounts[TR_ANN_UP] = 0;
tier->byteCounts[TR_ANN_DOWN] = 0;
tier->byteCounts[TR_ANN_CORRUPT] = 0;
}
if (!isStopped && tier->announce_event_count == 0)
{
/* the queue is empty, so enqueue a perodic update */
int const i = tier->announceIntervalSec;
dbgmsg(tier, "Sending periodic reannounce in %d seconds", i);
tier_announce_event_push(tier, TR_ANNOUNCE_EVENT_NONE, now + i);
}
}
}
tr_free(data);
}
static void announce_request_free(tr_announce_request* req)
{
tr_free(req->tracker_id_str);
tr_free(req);
}
static void announce_request_delegate(
tr_announcer* announcer,
tr_announce_request* request,
tr_announce_response_func callback,
void* callback_data)
{
tr_session* session = announcer->session;
#if 0
fprintf(stderr, "ANNOUNCE: event %s isPartialSeed %d port %d key %d numwant %d up %" PRIu64 " down %" PRIu64
" corrupt %" PRIu64 " left %" PRIu64 " url [%s] tracker_id_str [%s] peer_id [%20.20s]\n",
tr_announce_event_get_string(request->event), (int)request->partial_seed, (int)request->port, request->key,
request->numwant, request->up, request->down, request->corrupt, request->leftUntilComplete, request->url,
request->tracker_id_str, request->peer_id);
#endif
if (auto const announce_sv = request->announce_url.sv();
tr_strvStartsWith(announce_sv, "http://"sv) || tr_strvStartsWith(announce_sv, "https://"sv))
{
tr_tracker_http_announce(session, request, callback, callback_data);
}
else if (tr_strvStartsWith(announce_sv, "udp://"sv))
{
tr_tracker_udp_announce(session, request, callback, callback_data);
}
else
{
tr_logAddError("Unsupported url: %" TR_PRIsv, TR_PRIsv_ARG(announce_sv));
}
announce_request_free(request);
}
static void tierAnnounce(tr_announcer* announcer, tr_tier* tier)
{
TR_ASSERT(!tier->isAnnouncing);
TR_ASSERT(tier->announce_event_count > 0);
time_t const now = tr_time();
tr_torrent* tor = tier->tor;
tr_announce_event announce_event = tier_announce_event_pull(tier);
tr_announce_request* req = announce_request_new(announcer, tor, tier, announce_event);
auto* const data = tr_new0(struct announce_data, 1);
data->session = announcer->session;
data->tierId = tier->key;
data->isRunningOnSuccess = tor->isRunning;
data->timeSent = now;
data->event = announce_event;
tier->isAnnouncing = true;
tier->lastAnnounceStartTime = now;
announce_request_delegate(announcer, req, on_announce_done, data);
}
/***
****
**** SCRAPE
****
***/
static constexpr bool multiscrape_too_big(std::string_view errmsg)
{
/* Found a tracker that returns some bespoke string for this case?
Add your patch here and open a PR */
auto constexpr TooLongErrors = std::array<std::string_view, 3>{
"Bad Request",
"GET string too long",
"Request-URI Too Long",
};
for (auto const& tle : TooLongErrors)
{
if (tr_strvContains(errmsg, tle))
{
return true;
}
}
return false;
}
static void on_scrape_error(tr_session const* session, tr_tier* tier, char const* errmsg)
{
/* increment the error count */
if (tier->currentTracker != nullptr)
{
++tier->currentTracker->consecutiveFailures;
}
/* set the error message */
tr_strlcpy(tier->lastScrapeStr, errmsg, sizeof(tier->lastScrapeStr));
/* switch to the next tracker */
tierIncrementTracker(tier);
/* schedule a rescrape */
int const interval = getRetryInterval(tier->currentTracker);
auto const* const key_cstr = tier->currentTracker->key.c_str();
dbgmsg(tier, "Tracker '%s' scrape error: %s (Retrying in %zu seconds)", key_cstr, errmsg, (size_t)interval);
tr_logAddTorInfo(tier->tor, "Tracker '%s' error: %s (Retrying in %zu seconds)", key_cstr, errmsg, (size_t)interval);
tier->lastScrapeSucceeded = false;
tier->scrapeAt = get_next_scrape_time(session, tier, interval);
}
static tr_tier* find_tier(tr_torrent* tor, tr_interned_string scrape_url)
{
struct tr_announcer_tiers* tt = tor->announcer_tiers;
for (int i = 0; tt != nullptr && i < tt->tier_count; ++i)
{
tr_tracker const* const tracker = tt->tiers[i].currentTracker;
if (tracker != nullptr && tracker->scrape_info != nullptr && tracker->scrape_info->scrape_url == scrape_url)
{
return &tt->tiers[i];
}
}
return nullptr;
}
static void checkMultiscrapeMax(tr_announcer* announcer, tr_scrape_response const* response)
{
if (!multiscrape_too_big(response->errmsg))
{
return;
}
auto const& url = response->scrape_url;
struct tr_scrape_info* const scrape_info = tr_announcerGetScrapeInfo(announcer, url);
if (scrape_info == nullptr)
{
return;
}
// Lower the max only if it hasn't already lowered for a similar
// error. So if N parallel multiscrapes all have the same `max`
// and error out, lower the value once for that batch, not N times.
int& multiscrape_max = scrape_info->multiscrape_max;
if (multiscrape_max < response->row_count)
{
return;
}
int const n = std::max(1, int{ multiscrape_max - TrMultiscrapeStep });
if (multiscrape_max != n)
{
// don't log the full URL, since that might have a personal announce id
// (note: we know 'parsed' will be successful since this url has a scrape_info)
auto const parsed = *tr_urlParse(url.sv());
auto clean_url = std::string{};
tr_buildBuf(clean_url, parsed.scheme, "://"sv, parsed.host, ":"sv, parsed.portstr);
tr_logAddNamedInfo(clean_url.c_str(), "Reducing multiscrape max to %d", n);
multiscrape_max = n;
}
}
static void on_scrape_done(tr_scrape_response const* response, void* vsession)
{
time_t const now = tr_time();
auto* session = static_cast<tr_session*>(vsession);
tr_announcer* announcer = session->announcer;
for (int i = 0; i < response->row_count; ++i)
{
struct tr_scrape_response_row const* row = &response->rows[i];
tr_torrent* tor = session->getTorrent(row->info_hash);
if (tor != nullptr)
{
tr_tier* tier = find_tier(tor, response->scrape_url);
if (tier != nullptr)
{
auto const scrape_url_sv = response->scrape_url.sv();
dbgmsg(
tier,
"scraped url:%" TR_PRIsv
" -- "
"did_connect:%d "
"did_timeout:%d "
"seeders:%d "
"leechers:%d "
"downloads:%d "
"downloaders:%d "
"min_request_interval:%d "
"err:%s ",
TR_PRIsv_ARG(scrape_url_sv),
(int)response->did_connect,
(int)response->did_timeout,
row->seeders,
row->leechers,
row->downloads,
row->downloaders,
response->min_request_interval,
std::empty(response->errmsg) ? "none" : response->errmsg.c_str());
tier->isScraping = false;
tier->lastScrapeTime = now;
tier->lastScrapeSucceeded = false;
tier->lastScrapeTimedOut = response->did_timeout;
if (!response->did_connect)
{
on_scrape_error(session, tier, _("Could not connect to tracker"));
}
else if (response->did_timeout)
{
on_scrape_error(session, tier, _("Tracker did not respond"));
}
else if (!std::empty(response->errmsg))
{
on_scrape_error(session, tier, response->errmsg.c_str());
}
else
{
tier->lastScrapeSucceeded = true;
tier->scrapeIntervalSec = std::max(int{ DefaultScrapeIntervalSec }, response->min_request_interval);
tier->scrapeAt = get_next_scrape_time(session, tier, tier->scrapeIntervalSec);
tr_logAddTorDbg(tier->tor, "Scrape successful. Rescraping in %d seconds.", tier->scrapeIntervalSec);
tr_tracker* const tracker = tier->currentTracker;
if (tracker != nullptr)
{
if (row->seeders >= 0)
{
tracker->seederCount = row->seeders;
}
if (row->leechers >= 0)
{
tracker->leecherCount = row->leechers;
}
if (row->downloads >= 0)
{
tracker->downloadCount = row->downloads;
}
tracker->downloaderCount = row->downloaders;
tracker->consecutiveFailures = 0;
}
if (row->seeders >= 0 && row->leechers >= 0 && row->downloads >= 0)
{
publishPeerCounts(tier, row->seeders, row->leechers);
}
}
}
}
}
checkMultiscrapeMax(announcer, response);
}
static void scrape_request_delegate(
tr_announcer* announcer,
tr_scrape_request const* request,
tr_scrape_response_func callback,
void* callback_data)
{
tr_session* session = announcer->session;
auto const scrape_sv = request->scrape_url.sv();
if (tr_strvStartsWith(scrape_sv, "http://"sv) || tr_strvStartsWith(scrape_sv, "https://"sv))
{
tr_tracker_http_scrape(session, request, callback, callback_data);
}
else if (tr_strvStartsWith(scrape_sv, "udp://"sv))
{
tr_tracker_udp_scrape(session, request, callback, callback_data);
}
else
{
tr_logAddError("Unsupported url: %" TR_PRIsv, TR_PRIsv_ARG(scrape_sv));
}
}
static void multiscrape(tr_announcer* announcer, std::vector<tr_tier*> const& tiers)
{
size_t request_count = 0;
time_t const now = tr_time();
tr_scrape_request requests[MaxScrapesPerUpkeep] = {};
/* batch as many info_hashes into a request as we can */
for (auto* tier : tiers)
{
struct tr_scrape_info* const scrape_info = tier->currentTracker->scrape_info;
bool found = false;
TR_ASSERT(scrape_info != nullptr);
/* if there's a request with this scrape URL and a free slot, use it */
for (size_t j = 0; !found && j < request_count; ++j)
{
tr_scrape_request* req = &requests[j];
if (req->info_hash_count >= scrape_info->multiscrape_max)
{
continue;
}
if (scrape_info->scrape_url != req->scrape_url)
{
continue;
}
req->info_hash[req->info_hash_count] = tier->tor->infoHash();
++req->info_hash_count;
tier->isScraping = true;
tier->lastScrapeStartTime = now;
found = true;
}
/* otherwise, if there's room for another request, build a new one */
if (!found && request_count < MaxScrapesPerUpkeep)
{
tr_scrape_request* req = &requests[request_count++];
req->scrape_url = scrape_info->scrape_url;
tier_build_log_name(tier, req->log_name, sizeof(req->log_name));
req->info_hash[req->info_hash_count] = tier->tor->infoHash();
++req->info_hash_count;
tier->isScraping = true;
tier->lastScrapeStartTime = now;
}
}
/* send the requests we just built */
for (size_t i = 0; i < request_count; ++i)
{
scrape_request_delegate(announcer, &requests[i], on_scrape_done, announcer->session);
}
}
static void flushCloseMessages(tr_announcer* announcer)
{
auto& stops = announcer->stops;
std::for_each(
std::begin(stops),
std::end(stops),
[&announcer](auto* stop) { announce_request_delegate(announcer, stop, nullptr, nullptr); });
stops.clear();
}
static constexpr bool tierNeedsToAnnounce(tr_tier const* tier, time_t const now)
{
return !tier->isAnnouncing && !tier->isScraping && tier->announceAt != 0 && tier->announceAt <= now &&
tier->announce_event_count > 0;
}
static constexpr bool tierNeedsToScrape(tr_tier const* tier, time_t const now)
{
return !tier->isScraping && tier->scrapeAt != 0 && tier->scrapeAt <= now && tier->currentTracker != nullptr &&
tier->currentTracker->scrape_info != nullptr;
}
static constexpr int countDownloaders(tr_tier const* tier)
{
tr_tracker const* const tracker = tier->currentTracker;
return tracker == nullptr ? 0 : tracker->downloaderCount + tracker->leecherCount;
}
static int compareAnnounceTiers(tr_tier const* a, tr_tier const* b)
{
/* prefer higher-priority events */
if (auto const priority_a = a->announce_event_priority, priority_b = b->announce_event_priority; priority_a != priority_b)
{
return priority_a > priority_b ? -1 : 1;
}
/* prefer swarms where we might upload */
if (auto const leechers_a = countDownloaders(a), leechers_b = countDownloaders(b); leechers_a != leechers_b)
{
return leechers_a > leechers_b ? -1 : 1;
}
/* prefer swarms where we might download */
if (auto const is_done_a = a->tor->isDone(), is_done_b = b->tor->isDone(); is_done_a != is_done_b)
{
return is_done_a ? 1 : -1;
}
/* prefer larger stats, to help ensure stats get recorded when stopping on shutdown */
if (auto const xa = a->byteCounts[TR_ANN_UP] + a->byteCounts[TR_ANN_DOWN],
xb = b->byteCounts[TR_ANN_UP] + b->byteCounts[TR_ANN_DOWN];
xa != xb)
{
return xa > xb ? -1 : 1;
}
// announcements that have been waiting longer go first
if (a->announceAt != b->announceAt)
{
return a->announceAt < b->announceAt ? -1 : 1;
}
// the tiers are effectively equal priority, but add an arbitrary
// differentiation because ptrArray sorted mode hates equal items.
return a < b ? -1 : 1;
}
static void scrapeAndAnnounceMore(tr_announcer* announcer)
{
time_t const now = tr_time();
/* build a list of tiers that need to be announced */
auto announce_me = std::vector<tr_tier*>{};
auto scrape_me = std::vector<tr_tier*>{};
for (auto* tor : announcer->session->torrents)
{
struct tr_announcer_tiers* tt = tor->announcer_tiers;
for (int i = 0; tt != nullptr && i < tt->tier_count; ++i)
{
tr_tier* tier = &tt->tiers[i];
if (tierNeedsToAnnounce(tier, now))
{
announce_me.push_back(tier);
}
if (tierNeedsToScrape(tier, now))
{
scrape_me.push_back(tier);
}
}
}
/* First, scrape what we can. We handle scrapes first because
* we can work through that queue much faster than announces
* (thanks to multiscrape) _and_ the scrape responses will tell
* us which swarms are interesting and should be announced next. */
multiscrape(announcer, scrape_me);
/* Second, announce what we can. If there aren't enough slots
* available, use compareAnnounceTiers to prioritize. */
if (announce_me.size() > MaxAnnouncesPerUpkeep)
{
std::partial_sort(
std::begin(announce_me),
std::begin(announce_me) + MaxAnnouncesPerUpkeep,
std::end(announce_me),
[](auto const* a, auto const* b) { return compareAnnounceTiers(a, b) < 0; });
announce_me.resize(MaxAnnouncesPerUpkeep);
}
for (auto*& tier : announce_me)
{
tr_logAddTorDbg(tier->tor, "%s", "Announcing to tracker");
tierAnnounce(announcer, tier);
}
}
static void onUpkeepTimer(evutil_socket_t /*fd*/, short /*what*/, void* vannouncer)
{
auto* announcer = static_cast<tr_announcer*>(vannouncer);
tr_session* session = announcer->session;
auto const lock = session->unique_lock();
bool const is_closing = session->isClosed;
time_t const now = tr_time();
/* maybe send out some "stopped" messages for closed torrents */
flushCloseMessages(announcer);
/* maybe kick off some scrapes / announces whose time has come */
if (!is_closing)
{
scrapeAndAnnounceMore(announcer);
}
/* TAU upkeep */
if (announcer->tauUpkeepAt <= now)
{
announcer->tauUpkeepAt = now + TauUpkeepIntervalSecs;
tr_tracker_udp_upkeep(session);
}
/* set up the next timer */
tr_timerAddMsec(announcer->upkeepTimer, UpkeepIntervalMsec);
}
/***
****
***/
static tr_tracker_view trackerView(tr_torrent const& tor, int tier_index, tr_tier const& tier, tr_tracker const& tracker)
{
auto const now = tr_time();
auto view = tr_tracker_view{};
view.host = tracker.key.c_str();
view.announce = tracker.announce_url.c_str();
view.scrape = tracker.scrape_info == nullptr ? "" : tracker.scrape_info->scrape_url.c_str();
view.id = tracker.id;
view.tier = tier_index;
view.isBackup = &tracker != tier.currentTracker;
view.lastScrapeStartTime = tier.lastScrapeStartTime;
view.seederCount = tracker.seederCount;
view.leecherCount = tracker.leecherCount;
view.downloadCount = tracker.downloadCount;
if (view.isBackup)
{
view.scrapeState = TR_TRACKER_INACTIVE;
view.announceState = TR_TRACKER_INACTIVE;
view.nextScrapeTime = 0;
view.nextAnnounceTime = 0;
}
else
{
view.hasScraped = tier.lastScrapeTime;
if (view.hasScraped != 0)
{
view.lastScrapeTime = tier.lastScrapeTime;
view.lastScrapeSucceeded = tier.lastScrapeSucceeded;
view.lastScrapeTimedOut = tier.lastScrapeTimedOut;
tr_strlcpy(view.lastScrapeResult, tier.lastScrapeStr, sizeof(view.lastScrapeResult));
}
if (tier.isScraping)
{
view.scrapeState = TR_TRACKER_ACTIVE;
}
else if (tier.scrapeAt == 0)
{
view.scrapeState = TR_TRACKER_INACTIVE;
}
else if (tier.scrapeAt > now)
{
view.scrapeState = TR_TRACKER_WAITING;
view.nextScrapeTime = tier.scrapeAt;
}
else
{
view.scrapeState = TR_TRACKER_QUEUED;
}
view.lastAnnounceStartTime = tier.lastAnnounceStartTime;
view.hasAnnounced = tier.lastAnnounceTime;
if (view.hasAnnounced != 0)
{
view.lastAnnounceTime = tier.lastAnnounceTime;
view.lastAnnounceSucceeded = tier.lastAnnounceSucceeded;
view.lastAnnounceTimedOut = tier.lastAnnounceTimedOut;
view.lastAnnouncePeerCount = tier.lastAnnouncePeerCount;
tr_strlcpy(view.lastAnnounceResult, tier.lastAnnounceStr, sizeof(view.lastAnnounceResult));
}
if (tier.isAnnouncing)
{
view.announceState = TR_TRACKER_ACTIVE;
}
else if (!tor.isRunning || tier.announceAt == 0)
{
view.announceState = TR_TRACKER_INACTIVE;
}
else if (tier.announceAt > now)
{
view.announceState = TR_TRACKER_WAITING;
view.nextAnnounceTime = tier.announceAt;
}
else
{
view.announceState = TR_TRACKER_QUEUED;
}
}
TR_ASSERT(0 <= view.tier);
TR_ASSERT(view.tier < tor.announcer_tiers->tier_count);
return view;
}
size_t tr_announcerTrackerCount(tr_torrent const* tor)
{
TR_ASSERT(tr_isTorrent(tor));
TR_ASSERT(tor->announcer_tiers != nullptr);
return tor->announcer_tiers->tracker_count;
}
tr_tracker_view tr_announcerTracker(tr_torrent const* tor, size_t nth)
{
TR_ASSERT(tr_isTorrent(tor));
TR_ASSERT(tor->announcer_tiers != nullptr);
// find the nth tracker
struct tr_announcer_tiers const* const tt = tor->announcer_tiers;
if (nth >= size_t(tt->tracker_count))
{
return {};
}
auto const& tracker = tt->trackers[nth];
for (int i = 0; i < tt->tier_count; ++i)
{
tr_tier const& tier = tt->tiers[i];
for (int j = 0; j < tier.tracker_count; ++j)
{
if (&tier.trackers[j] == &tracker)
{
return trackerView(*tor, i, tier, tracker);
}
}
}
return {};
}
/***
****
***/
static void copy_tier_attributes_impl(struct tr_tier* tgt, int trackerIndex, tr_tier const* src)
{
/* sanity clause */
TR_ASSERT(trackerIndex < tgt->tracker_count);
TR_ASSERT(tgt->trackers[trackerIndex].announce_url == src->currentTracker->announce_url);
tr_tier const keep = *tgt;
/* bitwise copy will handle most of tr_tier's fields... */
*tgt = *src;
/* ...fix the fields that can't be cleanly bitwise-copied */
tgt->wasCopied = true;
tgt->trackers = keep.trackers;
tgt->tracker_count = keep.tracker_count;
tgt->announce_events = static_cast<tr_announce_event*>(
tr_memdup(src->announce_events, sizeof(tr_announce_event) * src->announce_event_count));
tgt->announce_event_priority = src->announce_event_priority;
tgt->announce_event_count = src->announce_event_count;
tgt->announce_event_alloc = src->announce_event_count;
tgt->currentTrackerIndex = trackerIndex;
tgt->currentTracker = &tgt->trackers[trackerIndex];
tgt->currentTracker->seederCount = src->currentTracker->seederCount;
tgt->currentTracker->leecherCount = src->currentTracker->leecherCount;
tgt->currentTracker->downloadCount = src->currentTracker->downloadCount;
tgt->currentTracker->downloaderCount = src->currentTracker->downloaderCount;
}
static void copy_tier_attributes(struct tr_announcer_tiers* tt, tr_tier const* src)
{
bool found = false;
/* find a tier (if any) which has a match for src->currentTracker */
for (int i = 0; !found && i < tt->tier_count; ++i)
{
for (int j = 0; !found && j < tt->tiers[i].tracker_count; ++j)
{
if (src->currentTracker->announce_url == tt->tiers[i].trackers[j].announce_url)
{
found = true;
copy_tier_attributes_impl(&tt->tiers[i], j, src);
}
}
}
}
void tr_announcerResetTorrent(tr_announcer* /*announcer*/, tr_torrent* tor)
{
TR_ASSERT(tor->announcer_tiers != nullptr);
time_t const now = tr_time();
tr_announcer_tiers* tt = tor->announcer_tiers;
tr_announcer_tiers old = *tt;
/* remove the old tiers / trackers */
tt->tiers = nullptr;
tt->trackers = nullptr;
tt->tier_count = 0;
tt->tracker_count = 0;
/* create the new tiers / trackers */
addTorrentToTier(tt, tor);
/* copy the old tiers' states into their replacements */
for (int i = 0; i < old.tier_count; ++i)
{
if (old.tiers[i].currentTracker != nullptr)
{
copy_tier_attributes(tt, &old.tiers[i]);
}
}
/* kickstart any tiers that didn't get started */
if (tor->isRunning)
{
for (int i = 0; i < tt->tier_count; ++i)
{
if (!tt->tiers[i].wasCopied)
{
tier_announce_event_push(&tt->tiers[i], TR_ANNOUNCE_EVENT_STARTED, now);
}
}
}
/* cleanup */
tiersDestruct(&old);
}