From c4cf8fa61d12eafe686ad05be4b4fe050bfb9285 Mon Sep 17 00:00:00 2001
From: Tatsuhiro Tsujikawa <tatsuhiro.t@gmail.com>
Date: Sat, 9 Jul 2016 21:34:40 +0900
Subject: [PATCH] Send have message without too much delay

Also send bitfield rather than have messages if bitfield message is
equal to or less than the sum of have messages which otherwise would
be sent.
---
 src/DefaultBtInteractive.cc | 41 +++++++++++++++----------------------
 src/DefaultBtInteractive.h  |  3 ---
 2 files changed, 16 insertions(+), 28 deletions(-)

diff --git a/src/DefaultBtInteractive.cc b/src/DefaultBtInteractive.cc
index ead26393..f844abb0 100644
--- a/src/DefaultBtInteractive.cc
+++ b/src/DefaultBtInteractive.cc
@@ -105,8 +105,7 @@ DefaultBtInteractive::DefaultBtInteractive(
       numReceivedMessage_(0),
       maxOutstandingRequest_(DEFAULT_MAX_OUTSTANDING_REQUEST),
       requestGroupMan_(nullptr),
-      tcpPort_(0),
-      haveLastSent_(global::wallclock())
+      tcpPort_(0)
 {
 }
 
@@ -264,37 +263,29 @@ void DefaultBtInteractive::decideChoking()
   }
 }
 
-namespace {
-constexpr auto MAX_HAVE_DELAY_SEC = 10_s;
-} // namespace
-
 void DefaultBtInteractive::checkHave()
 {
-  const size_t MIN_HAVE_PACK_SIZE = 20;
-  pieceStorage_->getAdvertisedPieceIndexes(haveIndexes_, cuid_, haveTimer_);
+  std::vector<size_t> haveIndexes;
+
+  pieceStorage_->getAdvertisedPieceIndexes(haveIndexes, cuid_, haveTimer_);
   haveTimer_ = global::wallclock();
-  if (haveIndexes_.size() >= MIN_HAVE_PACK_SIZE) {
+  // Use bitfield message if it is equal to or less than the total
+  // size of have messages.
+  if (5 + pieceStorage_->getBitfieldLength() <= haveIndexes.size() * 9) {
     if (peer_->isFastExtensionEnabled() &&
         pieceStorage_->allDownloadFinished()) {
       dispatcher_->addMessageToQueue(messageFactory_->createHaveAllMessage());
+
+      return;
     }
-    else {
-      dispatcher_->addMessageToQueue(messageFactory_->createBitfieldMessage());
-    }
-    haveIndexes_.clear();
+
+    dispatcher_->addMessageToQueue(messageFactory_->createBitfieldMessage());
+
+    return;
   }
-  else {
-    if (haveIndexes_.size() >= MIN_HAVE_PACK_SIZE ||
-        haveLastSent_.difference(global::wallclock()) >= MAX_HAVE_DELAY_SEC) {
-      haveLastSent_ = global::wallclock();
-      for (std::vector<size_t>::const_iterator itr = haveIndexes_.begin(),
-                                               eoi = haveIndexes_.end();
-           itr != eoi; ++itr) {
-        dispatcher_->addMessageToQueue(
-            messageFactory_->createHaveMessage(*itr));
-      }
-      haveIndexes_.clear();
-    }
+
+  for (auto idx : haveIndexes) {
+    dispatcher_->addMessageToQueue(messageFactory_->createHaveMessage(idx));
   }
 }
 
diff --git a/src/DefaultBtInteractive.h b/src/DefaultBtInteractive.h
index 15c99b0e..765201f7 100644
--- a/src/DefaultBtInteractive.h
+++ b/src/DefaultBtInteractive.h
@@ -144,9 +144,6 @@ private:
 
   uint16_t tcpPort_;
 
-  std::vector<size_t> haveIndexes_;
-  Timer haveLastSent_;
-
   void addBitfieldMessageToQueue();
   void addAllowedFastMessageToQueue();
   void addHandshakeExtendedMessageToQueue();