From 1290954f8d0d5c1f61caab9ac1aeacde500c9990 Mon Sep 17 00:00:00 2001
From: Varun Patil <varunpatil@ucla.edu>
Date: Fri, 8 Mar 2024 12:55:37 -0800
Subject: [PATCH] refactor(core): remove tuple

---
 ndn-svs/core.cpp | 35 ++++++++++++++---------------------
 ndn-svs/core.hpp | 24 +++++++++++++-----------
 2 files changed, 27 insertions(+), 32 deletions(-)

diff --git a/ndn-svs/core.cpp b/ndn-svs/core.cpp
index 2231fb9..fb0b484 100644
--- a/ndn-svs/core.cpp
+++ b/ndn-svs/core.cpp
@@ -71,9 +71,9 @@ suppressionCurve(int constFactor, int value)
   // Increasing the curve factor makes the curve steeper =>
   // better for more nodes, but worse for fewer nodes.
 
-  double c = constFactor;
-  double v = value;
-  double f = 10.0; // curve factor
+  float c = constFactor;
+  float v = value;
+  float f = 10.0; // curve factor
 
   return static_cast<int>(c * (1.0 - std::exp((v - c) / (c / f))));
 }
@@ -182,14 +182,11 @@ SVSyncCore::onSyncInterestValidated(const Interest& interest)
   // Merge state vector
   auto result = mergeStateVector(*vvOther);
 
-  bool myVectorNew = std::get<0>(result);
-  auto missingData = std::get<2>(result);
-
   // Callback if missing data found
-  if (!missingData.empty()) {
-    for (auto& e : missingData)
+  if (!result.missingInfo.empty()) {
+    for (auto& e : result.missingInfo)
       e.incomingFace = incomingFace;
-    m_onUpdate(missingData);
+    m_onUpdate(result.missingInfo);
   }
 
   // Try to record; the call will check if in suppression state
@@ -198,7 +195,7 @@ SVSyncCore::onSyncInterestValidated(const Interest& interest)
 
   // If incoming state identical/newer to local vector, reset timer
   // If incoming state is older, send sync interest immediately
-  if (!myVectorNew) {
+  if (!result.myVectorNew) {
     retxSyncInterest(false, 0);
   } else {
     enterSuppressionState(*vvOther);
@@ -224,7 +221,7 @@ SVSyncCore::retxSyncInterest(bool send, unsigned int delay)
 
     // Only send interest if in steady state or local vector has newer state
     // than recorded interests
-    if (!m_recordedVv || std::get<0>(mergeStateVector(*m_recordedVv)))
+    if (!m_recordedVv || mergeStateVector(*m_recordedVv).myVectorNew)
       sendSyncInterest();
     m_recordedVv = nullptr;
   }
@@ -301,15 +298,11 @@ SVSyncCore::sendSyncInterest()
   m_face.expressInterest(interest, nullptr, nullptr, nullptr);
 }
 
-std::tuple<bool, bool, std::vector<MissingDataInfo>>
+SVSyncCore::MergeResult
 SVSyncCore::mergeStateVector(const VersionVector& vvOther)
 {
   std::lock_guard<std::mutex> lock(m_vvMutex);
-
-  bool myVectorNew = false, otherVectorNew = false;
-
-  // New data found in vvOther
-  std::vector<MissingDataInfo> missingData;
+  SVSyncCore::MergeResult result;
 
   // Check if other vector has newer state
   for (const auto& entry : vvOther) {
@@ -318,10 +311,10 @@ SVSyncCore::mergeStateVector(const VersionVector& vvOther)
     SeqNo seqCurrent = m_vv.get(nidOther);
 
     if (seqCurrent < seqOther) {
-      otherVectorNew = true;
+      result.otherVectorNew = true;
 
       SeqNo startSeq = m_vv.get(nidOther) + 1;
-      missingData.push_back({ nidOther, startSeq, seqOther, 0 });
+      result.missingInfo.push_back({ nidOther, startSeq, seqOther, 0 });
 
       m_vv.set(nidOther, seqOther);
     }
@@ -338,12 +331,12 @@ SVSyncCore::mergeStateVector(const VersionVector& vvOther)
       continue;
 
     if (seqOther < seq) {
-      myVectorNew = true;
+      result.myVectorNew = true;
       break;
     }
   }
 
-  return { myVectorNew, otherVectorNew, missingData };
+  return result;
 }
 
 void
diff --git a/ndn-svs/core.hpp b/ndn-svs/core.hpp
index da4362b..c8c4985 100644
--- a/ndn-svs/core.hpp
+++ b/ndn-svs/core.hpp
@@ -172,22 +172,25 @@ class SVSyncCore : noncopyable
    */
   void sendSyncInterest();
 
+  struct MergeResult
+  {
+    /// @brief If the local state vector has newer entries
+    bool myVectorNew;
+    /// @brief If the incoming state vector has newer entries
+    bool otherVectorNew;
+    /// @brief Newly learned missing information from incoming state vector
+    std::vector<MissingDataInfo> missingInfo;
+  };
+
   /**
    * @brief Merge state vector into the current
-   *
-   * Also adds missing data interests to data interest queue.
-   *
    * @param vvOther state vector to merge in
-   *
-   * @returns a tuple of representing:
-   *    <my vector new, other vector new, missinginfo>.
+   * @details Also adds missing data interests to data interest queue.
    */
-  std::tuple<bool, bool, std::vector<MissingDataInfo>> mergeStateVector(
-    const VersionVector& vvOther);
+  MergeResult mergeStateVector(const VersionVector& vvOther);
 
   /**
    * @brief Record vector by merging it into m_recordedVv
-   *
    * @param vvOther state vector to merge in
    * @returns if recorded successfully
    */
@@ -195,8 +198,7 @@ class SVSyncCore : noncopyable
 
   /**
    * @brief Enter suppression state by setting
-   * m_recording to True and initializing m_recordedVv to vvOther
-   *
+   * m_recording to True and initializing m_recordedVv to vvOther.
    * Does nothing if already in suppression state
    *
    * @param vvOther first vector to record