validation: Move GetSpendHeight to BlockManager

[META] This commit should be followed up by removing the comments and
       assertions meant only to show that the change is correct.

GetSpendHeight only acts on BlockManager.

Author: dongcarl

src/txmempool.cpp

@@ -626,7 +626,7 @@ void CTxMemPool::check(const CCoinsViewCache *pcoins) const
     uint64_t innerUsage = 0;
 
     CCoinsViewCache mempoolDuplicate(const_cast<CCoinsViewCache*>(pcoins));
-    const int64_t spendheight = GetSpendHeight(mempoolDuplicate);
+    const int64_t spendheight = g_chainman.m_blockman.GetSpendHeight(mempoolDuplicate);
 
     std::list<const CTxMemPoolEntry*> waitingOnDependants;
     for (indexed_transaction_set::const_iterator it = mapTx.begin(); it != mapTx.end(); it++) {

src/validation.cpp

@@ -684,7 +684,7 @@ bool MemPoolAccept::PreChecks(ATMPArgs& args, Workspace& ws)
         return state.Invalid(TxValidationResult::TX_PREMATURE_SPEND, "non-BIP68-final");
 
     CAmount nFees = 0;
-    if (!Consensus::CheckTxInputs(tx, state, m_view, GetSpendHeight(m_view), nFees)) {
+    if (!Consensus::CheckTxInputs(tx, state, m_view, g_chainman.m_blockman.GetSpendHeight(m_view), nFees)) {
         return false; // state filled in by CheckTxInputs
     }
 
@@ -1412,10 +1412,11 @@ bool CScriptCheck::operator()() {
     return VerifyScript(scriptSig, m_tx_out.scriptPubKey, witness, nFlags, CachingTransactionSignatureChecker(ptxTo, nIn, m_tx_out.nValue, cacheStore, *txdata), &error);
 }
 
-int GetSpendHeight(const CCoinsViewCache& inputs)
+int BlockManager::GetSpendHeight(const CCoinsViewCache& inputs)
 {
-    LOCK(cs_main);
-    CBlockIndex* pindexPrev = g_chainman.m_blockman.LookupBlockIndex(inputs.GetBestBlock());
+    AssertLockHeld(cs_main);
+    assert(std::addressof(g_chainman.m_blockman) == std::addressof(*this));
+    CBlockIndex* pindexPrev = LookupBlockIndex(inputs.GetBestBlock());
     return pindexPrev->nHeight + 1;
 }
 

src/validation.h

@@ -433,6 +433,13 @@ class BlockManager
     /** Find the last common block between the parameter chain and a locator. */
     CBlockIndex* FindForkInGlobalIndex(const CChain& chain, const CBlockLocator& locator) EXCLUSIVE_LOCKS_REQUIRED(cs_main);
 
+    /**
+     * Return the spend height, which is one more than the inputs.GetBestBlock().
+     * While checking, GetBestBlock() refers to the parent block. (protected by cs_main)
+     * This is also true for mempool checks.
+     */
+    int GetSpendHeight(const CCoinsViewCache& inputs) EXCLUSIVE_LOCKS_REQUIRED(cs_main);
+
     ~BlockManager() {
         Unload();
     }
@@ -945,13 +952,6 @@ CChain& ChainActive();
 /** Global variable that points to the active block tree (protected by cs_main) */
 extern std::unique_ptr<CBlockTreeDB> pblocktree;
 
-/**
- * Return the spend height, which is one more than the inputs.GetBestBlock().
- * While checking, GetBestBlock() refers to the parent block. (protected by cs_main)
- * This is also true for mempool checks.
- */
-int GetSpendHeight(const CCoinsViewCache& inputs);
-
 extern VersionBitsCache versionbitscache;
 
 /**