From e57980b4738c10344baf136de3e050a3cb958ca5 Mon Sep 17 00:00:00 2001
From: John Newbery <john@johnnewbery.com>
Date: Mon, 11 Nov 2019 10:53:03 -0500
Subject: [PATCH] [mempool] Remove NotifyEntryAdded and NotifyEntryRemoved
 callbacks

NotifyEntryAdded never had any subscribers so can be removed.

Since ConnectTrace no longer subscribes to NotifyEntryRemoved, there are
now no subscribers.

The CValidationInterface TransactionAddedToMempool and
TransactionRemovedFromMempool methods can now provide this
functionality. There's no need for a special notifications framework for
the mempool.
---
 src/init.cpp            | 1 +
 src/interfaces/node.cpp | 2 ++
 src/txmempool.cpp       | 5 +----
 src/txmempool.h         | 4 ----
 4 files changed, 4 insertions(+), 8 deletions(-)

diff --git a/src/init.cpp b/src/init.cpp
index ece6214aa8f..bcc3d83af8f 100644
--- a/src/init.cpp
+++ b/src/init.cpp
@@ -74,6 +74,7 @@
 #include <boost/algorithm/string/classification.hpp>
 #include <boost/algorithm/string/replace.hpp>
 #include <boost/algorithm/string/split.hpp>
+#include <boost/signals2/signal.hpp>
 #include <boost/thread.hpp>
 
 #if ENABLE_ZMQ
diff --git a/src/interfaces/node.cpp b/src/interfaces/node.cpp
index 8a64a9d26aa..b720a630179 100644
--- a/src/interfaces/node.cpp
+++ b/src/interfaces/node.cpp
@@ -37,6 +37,8 @@
 
 #include <univalue.h>
 
+#include <boost/signals2/signal.hpp>
+
 class CWallet;
 fs::path GetWalletDir();
 std::vector<fs::path> ListWalletDir();
diff --git a/src/txmempool.cpp b/src/txmempool.cpp
index f04f13e6e00..47b0d39ea4c 100644
--- a/src/txmempool.cpp
+++ b/src/txmempool.cpp
@@ -355,7 +355,6 @@ void CTxMemPool::AddTransactionsUpdated(unsigned int n)
 
 void CTxMemPool::addUnchecked(const CTxMemPoolEntry &entry, setEntries &setAncestors, bool validFeeEstimate)
 {
-    NotifyEntryAdded(entry.GetSharedTx());
     // Add to memory pool without checking anything.
     // Used by AcceptToMemoryPool(), which DOES do
     // all the appropriate checks.
@@ -406,14 +405,12 @@ void CTxMemPool::addUnchecked(const CTxMemPoolEntry &entry, setEntries &setAnces
 
 void CTxMemPool::removeUnchecked(txiter it, MemPoolRemovalReason reason)
 {
-    CTransactionRef ptx = it->GetSharedTx();
-    NotifyEntryRemoved(ptx, reason);
     if (reason != MemPoolRemovalReason::BLOCK) {
         // Notify clients that a transaction has been removed from the mempool
         // for any reason except being included in a block. Clients interested
         // in transactions included in blocks can subscribe to the BlockConnected
         // notification.
-        GetMainSignals().TransactionRemovedFromMempool(ptx);
+        GetMainSignals().TransactionRemovedFromMempool(it->GetSharedTx());
     }
 
     const uint256 hash = it->GetTx().GetHash();
diff --git a/src/txmempool.h b/src/txmempool.h
index de11d626b41..38a4667b317 100644
--- a/src/txmempool.h
+++ b/src/txmempool.h
@@ -27,7 +27,6 @@
 #include <boost/multi_index/hashed_index.hpp>
 #include <boost/multi_index/ordered_index.hpp>
 #include <boost/multi_index/sequenced_index.hpp>
-#include <boost/signals2/signal.hpp>
 
 class CBlockIndex;
 extern RecursiveMutex cs_main;
@@ -699,9 +698,6 @@ public:
 
     size_t DynamicMemoryUsage() const;
 
-    boost::signals2::signal<void (CTransactionRef)> NotifyEntryAdded;
-    boost::signals2::signal<void (CTransactionRef, MemPoolRemovalReason)> NotifyEntryRemoved;
-
 private:
     /** UpdateForDescendants is used by UpdateTransactionsFromBlock to update
      *  the descendants for a single transaction that has been added to the