rpc: getTransactionsUpdated via miner interface

Author: Sjors

src/interfaces/mining.h

@@ -41,6 +41,10 @@ class Mining
      */
     virtual std::unique_ptr<node::CBlockTemplate> createNewBlock(const CScript& script_pub_key, bool use_mempool = true) = 0;
 
+    //! Return the number of transaction updates in the mempool,
+    //! used to decide whether to make a new block template.
+    virtual unsigned int getTransactionsUpdated() = 0;
+
     /**
      * Check a block is completely valid from start to finish.
      * Only works on top of our current best block.

src/node/interfaces.cpp

@@ -855,6 +855,11 @@ class MinerImpl : public Mining
         return tip->GetBlockHash();
     }
 
+    unsigned int getTransactionsUpdated() override
+    {
+        return context()->mempool->GetTransactionsUpdated();
+    }
+
     bool testBlockValidity(BlockValidationState& state, const CBlock& block, bool check_merkle_root) override
     {
         LOCK(::cs_main);

src/rpc/mining.cpp

@@ -738,7 +738,6 @@ static RPCHelpMan getblocktemplate()
     }
 
     static unsigned int nTransactionsUpdatedLast;
-    const CTxMemPool& mempool = EnsureMemPool(node);
 
     if (!lpval.isNull())
     {
@@ -774,7 +773,7 @@ static RPCHelpMan getblocktemplate()
                 {
                     // Timeout: Check transactions for update
                     // without holding the mempool lock to avoid deadlocks
-                    if (mempool.GetTransactionsUpdated() != nTransactionsUpdatedLastLP)
+                    if (miner.getTransactionsUpdated() != nTransactionsUpdatedLastLP)
                         break;
                     checktxtime += std::chrono::seconds(10);
                 }
@@ -804,13 +803,13 @@ static RPCHelpMan getblocktemplate()
     static int64_t time_start;
     static std::unique_ptr<CBlockTemplate> pblocktemplate;
     if (!pindexPrev || pindexPrev->GetBlockHash() != miner.getTipHash() ||
-        (mempool.GetTransactionsUpdated() != nTransactionsUpdatedLast && GetTime() - time_start > 5))
+        (miner.getTransactionsUpdated() != nTransactionsUpdatedLast && GetTime() - time_start > 5))
     {
         // Clear pindexPrev so future calls make a new block, despite any failures from here on
         pindexPrev = nullptr;
 
         // Store the pindexBest used before createNewBlock, to avoid races
-        nTransactionsUpdatedLast = mempool.GetTransactionsUpdated();
+        nTransactionsUpdatedLast = miner.getTransactionsUpdated();
         CBlockIndex* pindexPrevNew = chainman.m_blockman.LookupBlockIndex(miner.getTipHash());
         time_start = GetTime();