fix tracker selection

src/AnnounceList.cc

@@ -109,10 +109,15 @@ void AnnounceList::announceSuccess()
  if (currentTrackerInitialized_) {
  (*currentTier_)->nextEvent();
  auto url = *currentTracker_;
- (*currentTier_)->urls.erase(currentTracker_);
+ currentTracker_ = (*currentTier_)->urls.erase(currentTracker_);
  (*currentTier_)->urls.push_front(std::move(url));
- currentTier_ = std::begin(tiers_);
- currentTracker_ = std::begin((*currentTier_)->urls);
+ if (currentTracker_ == std::end((*currentTier_)->urls)) {
+ ++currentTier_;
+ if (currentTier_ == std::end(tiers_)) {
+ currentTier_ = std::begin(tiers_);
+ }
+ currentTracker_ = std::begin((*currentTier_)->urls);
+ }
  }
 }
 

src/AnnounceList.h

@@ -95,8 +95,9 @@ class AnnounceList {
  /**
  * Removes current announce URL from its group and inserts it before the
  * first element of the group.
- * The internal announce group pointer points to the first element of the
- * first group after this call.
+ * The internal announce group pointer points to the next element.
+ * If the current URL is the last element of its group, then the first
+ * element of the next group is pointed.
  */
  void announceSuccess();