refactor: use std::function for announcer callback (#4575)

libtransmission/announcer.cc

@@ -622,7 +622,7 @@ struct tr_torrent_announcer
 
     std::vector<tr_tier> tiers;
 
-    tr_tracker_callback callback = nullptr;
+    tr_tracker_callback callback;
 
 private:
     [[nodiscard]] static tr_announce_list getAnnounceList(tr_torrent const* tor)
@@ -660,7 +660,7 @@ void publishMessage(tr_tier* tier, std::string_view msg, tr_tracker_event::Type
             event.announce_url = current_tracker->announce_url;
         }
 
-        (*ta->callback)(tier->tor, &event);
+        ta->callback(*tier->tor, &event);
     }
 }
 
@@ -689,7 +689,7 @@ void publishPeerCounts(tr_tier* tier, int seeders, int leechers)
         e.leechers = leechers;
         tr_logAddDebugTier(tier, fmt::format("peer counts: {} seeders, {} leechers.", seeders, leechers));
 
-        (*tier->tor->torrent_announcer->callback)(tier->tor, &e);
+        tier->tor->torrent_announcer->callback(*tier->tor, &e);
     }
 }
 
@@ -710,7 +710,7 @@ void publishPeersPex(tr_tier* tier, int seeders, int leechers, std::vector<tr_pe
                 leechers,
                 std::size(pex)));
 
-        (*tier->tor->torrent_announcer->callback)(tier->tor, &e);
+        tier->tor->torrent_announcer->callback(*tier->tor, &e);
     }
 }
 } // namespace publish_helpers

libtransmission/announcer.h

@@ -59,7 +59,7 @@ struct tr_tracker_event
     int seeders;
 };
 
-using tr_tracker_callback = void (*)(tr_torrent* tor, tr_tracker_event const* event);
+using tr_tracker_callback = std::function<void(tr_torrent&, tr_tracker_event const*)>;
 
 class tr_announcer
 {

libtransmission/torrent.cc

@@ -1025,46 +1025,6 @@ bool isNewTorrentASeed(tr_torrent* tor)
     return tor->ensurePieceIsChecked(0);
 }
 
-void onTrackerResponse(tr_torrent* tor, tr_tracker_event const* event)
-{
-    switch (event->type)
-    {
-    case tr_tracker_event::Type::Peers:
-        tr_logAddTraceTor(tor, fmt::format("Got {} peers from tracker", std::size(event->pex)));
-        tr_peerMgrAddPex(tor, TR_PEER_FROM_TRACKER, std::data(event->pex), std::size(event->pex));
-        break;
-
-    case tr_tracker_event::Type::Counts:
-        if (tor->isPrivate() && (event->leechers == 0))
-        {
-            tr_peerMgrSetSwarmIsAllSeeds(tor);
-        }
-
-        break;
-
-    case tr_tracker_event::Type::Warning:
-        tr_logAddWarnTor(tor, fmt::format(_("Tracker warning: '{warning}'"), fmt::arg("warning", event->text)));
-        tor->error = TR_STAT_TRACKER_WARNING;
-        tor->error_announce_url = event->announce_url;
-        tor->error_string = event->text;
-        break;
-
-    case tr_tracker_event::Type::Error:
-        tor->error = TR_STAT_TRACKER_ERROR;
-        tor->error_announce_url = event->announce_url;
-        tor->error_string = event->text;
-        break;
-
-    case tr_tracker_event::Type::ErrorClear:
-        if (tor->error != TR_STAT_LOCAL_ERROR)
-        {
-            tr_torrentClearError(tor);
-        }
-
-        break;
-    }
-}
-
 void torrentInitFromInfoDict(tr_torrent* tor)
 {
     tor->completion = tr_completion{ tor, &tor->blockInfo() };
@@ -1212,7 +1172,7 @@ void torrentInit(tr_torrent* tor, tr_ctor const* ctor)
         }
     }
 
-    tor->torrent_announcer = session->announcer_->addTorrent(tor, onTrackerResponse);
+    tor->torrent_announcer = session->announcer_->addTorrent(tor, &tr_torrent::onTrackerResponse);
 
     if (is_new_torrent)
     {
@@ -2235,6 +2195,46 @@ bool tr_torrent::setTrackerList(std::string_view text)
     return true;
 }
 
+void tr_torrent::onTrackerResponse(tr_tracker_event const* event)
+{
+    switch (event->type)
+    {
+    case tr_tracker_event::Type::Peers:
+        tr_logAddTraceTor(this, fmt::format("Got {} peers from tracker", std::size(event->pex)));
+        tr_peerMgrAddPex(this, TR_PEER_FROM_TRACKER, std::data(event->pex), std::size(event->pex));
+        break;
+
+    case tr_tracker_event::Type::Counts:
+        if (isPrivate() && (event->leechers == 0))
+        {
+            tr_peerMgrSetSwarmIsAllSeeds(this);
+        }
+
+        break;
+
+    case tr_tracker_event::Type::Warning:
+        tr_logAddWarnTor(this, fmt::format(_("Tracker warning: '{warning}'"), fmt::arg("warning", event->text)));
+        error = TR_STAT_TRACKER_WARNING;
+        error_announce_url = event->announce_url;
+        error_string = event->text;
+        break;
+
+    case tr_tracker_event::Type::Error:
+        error = TR_STAT_TRACKER_ERROR;
+        error_announce_url = event->announce_url;
+        error_string = event->text;
+        break;
+
+    case tr_tracker_event::Type::ErrorClear:
+        if (error != TR_STAT_LOCAL_ERROR)
+        {
+            tr_torrentClearError(this);
+        }
+
+        break;
+    }
+}
+
 bool tr_torrentSetTrackerList(tr_torrent* tor, char const* text)
 {
     return text != nullptr && tor->setTrackerList(text);

libtransmission/torrent.h

@@ -432,6 +432,8 @@ public:
 
     bool setTrackerList(std::string_view text);
 
+    void onTrackerResponse(tr_tracker_event const* event);
+
     /// METAINFO - WEBSEEDS
 
     [[nodiscard]] TR_CONSTEXPR20 auto webseedCount() const noexcept