1 files changed, 65 insertions, 52 deletions

diff --git a/src/validation.cpp b/src/validation.cpp
index f4b316f67a..208bcee008 100644
--- a/src/validation.cpp
+++ b/src/validation.cpp
@@ -19,7 +19,6 @@
 #include <deploymentstatus.h>
 #include <flatfile.h>
 #include <hash.h>
-#include <index/blockfilterindex.h>
 #include <logging.h>
 #include <logging/timer.h>
 #include <node/blockstorage.h>
@@ -69,7 +68,6 @@ using node::CBlockIndexHeightOnlyComparator;
 using node::CBlockIndexWorkComparator;
 using node::CCoinsStats;
 using node::CoinStatsHashType;
-using node::fHavePruned;
 using node::fImporting;
 using node::fPruneMode;
 using node::fReindex;
@@ -107,6 +105,12 @@ const std::vector<std::string> CHECKLEVEL_DOC {
     "level 4 tries to reconnect the blocks",
     "each level includes the checks of the previous levels",
 };
+/** The number of blocks to keep below the deepest prune lock.
+ *  There is nothing special about this number. It is higher than what we
+ *  expect to see in regular mainnet reorgs, but not so high that it would
+ *  noticeably interfere with the pruning mechanism.
+ * */
+static constexpr int PRUNE_LOCK_BUFFER{10};
 
 /**
  * Mutex to guard access to validation specific variables, such as reading
@@ -120,7 +124,6 @@ const std::vector<std::string> CHECKLEVEL_DOC {
  */
 RecursiveMutex cs_main;
 
-CBlockIndex *pindexBestHeader = nullptr;
 Mutex g_best_block_mutex;
 std::condition_variable g_best_block_cv;
 uint256 g_best_block;
@@ -280,8 +283,9 @@ static bool IsCurrentForFeeEstimation(CChainState& active_chainstate) EXCLUSIVE_
         return false;
     if (active_chainstate.m_chain.Tip()->GetBlockTime() < count_seconds(GetTime<std::chrono::seconds>() - MAX_FEE_ESTIMATION_TIP_AGE))
         return false;
-    if (active_chainstate.m_chain.Height() < pindexBestHeader->nHeight - 1)
+    if (active_chainstate.m_chain.Height() < active_chainstate.m_chainman.m_best_header->nHeight - 1) {
         return false;
+    }
     return true;
 }
 
@@ -1602,8 +1606,8 @@ void CChainState::InvalidChainFound(CBlockIndex* pindexNew)
     if (!m_chainman.m_best_invalid || pindexNew->nChainWork > m_chainman.m_best_invalid->nChainWork) {
         m_chainman.m_best_invalid = pindexNew;
     }
-    if (pindexBestHeader != nullptr && pindexBestHeader->GetAncestor(pindexNew->nHeight) == pindexNew) {
-        pindexBestHeader = m_chain.Tip();
+    if (m_chainman.m_best_header != nullptr && m_chainman.m_best_header->GetAncestor(pindexNew->nHeight) == pindexNew) {
+        m_chainman.m_best_header = m_chain.Tip();
     }
 
     LogPrintf("%s: invalid block=%s  height=%d  log2_work=%f  date=%s\n", __func__,
@@ -1917,7 +1921,7 @@ public:
     }
 };
 
-static ThresholdConditionCache warningcache[VERSIONBITS_NUM_BITS] GUARDED_BY(cs_main);
+static std::array<ThresholdConditionCache, VERSIONBITS_NUM_BITS> warningcache GUARDED_BY(cs_main);
 
 static unsigned int GetBlockScriptFlags(const CBlockIndex& block_index, const Consensus::Params& consensusparams)
 {
@@ -2029,8 +2033,8 @@ bool CChainState::ConnectBlock(const CBlock& block, BlockValidationState& state,
         BlockMap::const_iterator  it = m_blockman.m_block_index.find(hashAssumeValid);
         if (it != m_blockman.m_block_index.end()) {
             if (it->second.GetAncestor(pindex->nHeight) == pindex &&
-                pindexBestHeader->GetAncestor(pindex->nHeight) == pindex &&
-                pindexBestHeader->nChainWork >= nMinimumChainWork) {
+                m_chainman.m_best_header->GetAncestor(pindex->nHeight) == pindex &&
+                m_chainman.m_best_header->nChainWork >= nMinimumChainWork) {
                 // This block is a member of the assumed verified chain and an ancestor of the best header.
                 // Script verification is skipped when connecting blocks under the
                 // assumevalid block. Assuming the assumevalid block is valid this
@@ -2045,7 +2049,7 @@ bool CChainState::ConnectBlock(const CBlock& block, BlockValidationState& state,
                 //  artificially set the default assumed verified block further back.
                 // The test against nMinimumChainWork prevents the skipping when denied access to any chain at
                 //  least as good as the expected chain.
-                fScriptChecks = (GetBlockProofEquivalentTime(*pindexBestHeader, *pindex, *pindexBestHeader, m_params.GetConsensus()) <= 60 * 60 * 24 * 7 * 2);
+                fScriptChecks = (GetBlockProofEquivalentTime(*m_chainman.m_best_header, *pindex, *m_chainman.m_best_header, m_params.GetConsensus()) <= 60 * 60 * 24 * 7 * 2);
             }
         }
     }
@@ -2339,12 +2343,24 @@ bool CChainState::FlushStateToDisk(
         CoinsCacheSizeState cache_state = GetCoinsCacheSizeState();
         LOCK(m_blockman.cs_LastBlockFile);
         if (fPruneMode && (m_blockman.m_check_for_pruning || nManualPruneHeight > 0) && !fReindex) {
-            // make sure we don't prune above the blockfilterindexes bestblocks
+            // make sure we don't prune above any of the prune locks bestblocks
             // pruning is height-based
-            int last_prune = m_chain.Height(); // last height we can prune
-            ForEachBlockFilterIndex([&](BlockFilterIndex& index) {
-               last_prune = std::max(1, std::min(last_prune, index.GetSummary().best_block_height));
-            });
+            int last_prune{m_chain.Height()}; // last height we can prune
+            std::optional<std::string> limiting_lock; // prune lock that actually was the limiting factor, only used for logging
+
+            for (const auto& prune_lock : m_blockman.m_prune_locks) {
+                if (prune_lock.second.height_first == std::numeric_limits<int>::max()) continue;
+                // Remove the buffer and one additional block here to get actual height that is outside of the buffer
+                const int lock_height{prune_lock.second.height_first - PRUNE_LOCK_BUFFER - 1};
+                last_prune = std::max(1, std::min(last_prune, lock_height));
+                if (last_prune == lock_height) {
+                    limiting_lock = prune_lock.first;
+                }
+            }
+
+            if (limiting_lock) {
+                LogPrint(BCLog::PRUNE, "%s limited pruning to height %d\n", limiting_lock.value(), last_prune);
+            }
 
             if (nManualPruneHeight > 0) {
                 LOG_TIME_MILLIS_WITH_CATEGORY("find files to prune (manual)", BCLog::BENCH);
@@ -2358,9 +2374,9 @@ bool CChainState::FlushStateToDisk(
             }
             if (!setFilesToPrune.empty()) {
                 fFlushForPrune = true;
-                if (!fHavePruned) {
+                if (!m_blockman.m_have_pruned) {
                     m_blockman.m_block_tree_db->WriteFlag("prunedblockfiles", true);
-                    fHavePruned = true;
+                    m_blockman.m_have_pruned = true;
                 }
             }
         }
@@ -2534,7 +2550,7 @@ void CChainState::UpdateTip(const CBlockIndex* pindexNew)
         const CBlockIndex* pindex = pindexNew;
         for (int bit = 0; bit < VERSIONBITS_NUM_BITS; bit++) {
             WarningBitsConditionChecker checker(bit);
-            ThresholdState state = checker.GetStateFor(pindex, m_params.GetConsensus(), warningcache[bit]);
+            ThresholdState state = checker.GetStateFor(pindex, m_params.GetConsensus(), warningcache.at(bit));
             if (state == ThresholdState::ACTIVE || state == ThresholdState::LOCKED_IN) {
                 const bilingual_str warning = strprintf(_("Unknown new rules activated (versionbit %i)"), bit);
                 if (state == ThresholdState::ACTIVE) {
@@ -2582,6 +2598,18 @@ bool CChainState::DisconnectTip(BlockValidationState& state, DisconnectedBlockTr
         assert(flushed);
     }
     LogPrint(BCLog::BENCH, "- Disconnect block: %.2fms\n", (GetTimeMicros() - nStart) * MILLI);
+
+    {
+        // Prune locks that began at or after the tip should be moved backward so they get a chance to reorg
+        const int max_height_first{pindexDelete->nHeight - 1};
+        for (auto& prune_lock : m_blockman.m_prune_locks) {
+            if (prune_lock.second.height_first <= max_height_first) continue;
+
+            prune_lock.second.height_first = max_height_first;
+            LogPrint(BCLog::PRUNE, "%s prune lock moved back to %d\n", prune_lock.first, max_height_first);
+        }
+    }
+
     // Write the chain state to disk, if necessary.
     if (!FlushStateToDisk(state, FlushStateMode::IF_NEEDED)) {
         return false;
@@ -2904,7 +2932,7 @@ static bool NotifyHeaderTip(CChainState& chainstate) LOCKS_EXCLUDED(cs_main) {
     CBlockIndex* pindexHeader = nullptr;
     {
         LOCK(cs_main);
-        pindexHeader = pindexBestHeader;
+        pindexHeader = chainstate.m_chainman.m_best_header;
 
         if (pindexHeader != pindexHeaderOld) {
             fNotify = true;
@@ -3621,7 +3649,7 @@ bool ChainstateManager::AcceptBlockHeader(const CBlockHeader& block, BlockValida
             }
         }
     }
-    CBlockIndex* pindex{m_blockman.AddToBlockIndex(block)};
+    CBlockIndex* pindex{m_blockman.AddToBlockIndex(block, m_best_header)};
 
     if (ppindex)
         *ppindex = pindex;
@@ -4115,22 +4143,6 @@ void CChainState::UnloadBlockIndex()
     setBlockIndexCandidates.clear();
 }
 
-// May NOT be used after any connections are up as much
-// of the peer-processing logic assumes a consistent
-// block index state
-void UnloadBlockIndex(CTxMemPool* mempool, ChainstateManager& chainman)
-{
-    AssertLockHeld(::cs_main);
-    chainman.Unload();
-    pindexBestHeader = nullptr;
-    if (mempool) mempool->clear();
-    g_versionbitscache.Clear();
-    for (int b = 0; b < VERSIONBITS_NUM_BITS; b++) {
-        warningcache[b].clear();
-    }
-    fHavePruned = false;
-}
-
 bool ChainstateManager::LoadBlockIndex()
 {
     AssertLockHeld(cs_main);
@@ -4203,6 +4215,8 @@ bool ChainstateManager::LoadBlockIndex()
             if (pindex->nStatus & BLOCK_FAILED_MASK && (!m_best_invalid || pindex->nChainWork > m_best_invalid->nChainWork)) {
                 m_best_invalid = pindex;
             }
+            if (pindex->IsValid(BLOCK_VALID_TREE) && (m_best_header == nullptr || CBlockIndexWorkComparator()(m_best_header, pindex)))
+                m_best_header = pindex;
         }
 
         needs_init = m_blockman.m_block_index.empty();
@@ -4237,7 +4251,7 @@ bool CChainState::LoadGenesisBlock()
         if (blockPos.IsNull()) {
             return error("%s: writing genesis block to disk failed", __func__);
         }
-        CBlockIndex *pindex = m_blockman.AddToBlockIndex(block);
+        CBlockIndex* pindex = m_blockman.AddToBlockIndex(block, m_chainman.m_best_header);
         ReceivedBlockTransactions(block, pindex, blockPos);
     } catch (const std::runtime_error& e) {
         return error("%s: failed to write genesis block: %s", __func__, e.what());
@@ -4448,7 +4462,7 @@ void CChainState::CheckBlockIndex()
         // HAVE_DATA is only equivalent to nTx > 0 (or VALID_TRANSACTIONS) if no pruning has occurred.
         // Unless these indexes are assumed valid and pending block download on a
         // background chainstate.
-        if (!fHavePruned && !pindex->IsAssumedValid()) {
+        if (!m_blockman.m_have_pruned && !pindex->IsAssumedValid()) {
             // If we've never pruned, then HAVE_DATA should be equivalent to nTx > 0
             assert(!(pindex->nStatus & BLOCK_HAVE_DATA) == (pindex->nTx == 0));
             assert(pindexFirstMissing == pindexFirstNeverProcessed);
@@ -4522,7 +4536,7 @@ void CChainState::CheckBlockIndex()
         if (pindexFirstMissing == nullptr) assert(!foundInUnlinked); // We aren't missing data for any parent -- cannot be in m_blocks_unlinked.
         if (pindex->pprev && (pindex->nStatus & BLOCK_HAVE_DATA) && pindexFirstNeverProcessed == nullptr && pindexFirstMissing != nullptr) {
             // We HAVE_DATA for this block, have received data for all parents at some point, but we're currently missing data for some parent.
-            assert(fHavePruned); // We must have pruned.
+            assert(m_blockman.m_have_pruned); // We must have pruned.
             // This block may have entered m_blocks_unlinked if:
             //  - it has a descendant that at some point had more work than the
             //    tip, and
@@ -5159,19 +5173,6 @@ bool ChainstateManager::IsSnapshotActive() const
     return m_snapshot_chainstate && m_active_chainstate == m_snapshot_chainstate.get();
 }
 
-void ChainstateManager::Unload()
-{
-    AssertLockHeld(::cs_main);
-    for (CChainState* chainstate : this->GetAll()) {
-        chainstate->m_chain.SetTip(nullptr);
-        chainstate->UnloadBlockIndex();
-    }
-
-    m_failed_blocks.clear();
-    m_blockman.Unload();
-    m_best_invalid = nullptr;
-}
-
 void ChainstateManager::MaybeRebalanceCaches()
 {
     AssertLockHeld(::cs_main);
@@ -5202,3 +5203,15 @@ void ChainstateManager::MaybeRebalanceCaches()
         }
     }
 }
+
+ChainstateManager::~ChainstateManager()
+{
+    LOCK(::cs_main);
+
+    // TODO: The version bits cache and warning cache should probably become
+    // non-globals
+    g_versionbitscache.Clear();
+    for (auto& i : warningcache) {
+        i.clear();
+    }
+}