diff options
Diffstat (limited to 'src/index')
| -rw-r--r-- | src/index/txindex.cpp | 157 | ||||
| -rw-r--r-- | src/index/txindex.h | 60 |
2 files changed, 217 insertions, 0 deletions
diff --git a/src/index/txindex.cpp b/src/index/txindex.cpp new file mode 100644 index 0000000000..27cf844ceb --- /dev/null +++ b/src/index/txindex.cpp @@ -0,0 +1,157 @@ +// Copyright (c) 2017-2018 The Bitcoin Core developers +// Distributed under the MIT software license, see the accompanying +// file COPYING or http://www.opensource.org/licenses/mit-license.php. + +#include <index/txindex.h> +#include <init.h> +#include <tinyformat.h> +#include <ui_interface.h> +#include <util.h> +#include <validation.h> +#include <warnings.h> + +template<typename... Args> +static void FatalError(const char* fmt, const Args&... args) +{ + std::string strMessage = tfm::format(fmt, args...); + SetMiscWarning(strMessage); + LogPrintf("*** %s\n", strMessage); + uiInterface.ThreadSafeMessageBox( + "Error: A fatal internal error occurred, see debug.log for details", + "", CClientUIInterface::MSG_ERROR); + StartShutdown(); +} + +TxIndex::TxIndex(std::unique_ptr<TxIndexDB> db) : + m_db(std::move(db)), m_synced(false), m_best_block_index(nullptr) +{} + +bool TxIndex::Init() +{ + LOCK(cs_main); + + // Attempt to migrate txindex from the old database to the new one. Even if + // chain_tip is null, the node could be reindexing and we still want to + // delete txindex records in the old database. + if (!m_db->MigrateData(*pblocktree, chainActive.GetLocator())) { + return false; + } + + CBlockLocator locator; + if (!m_db->ReadBestBlock(locator)) { + locator.SetNull(); + } + + m_best_block_index = FindForkInGlobalIndex(chainActive, locator); + m_synced = m_best_block_index.load() == chainActive.Tip(); + return true; +} + +bool TxIndex::WriteBlock(const CBlock& block, const CBlockIndex* pindex) +{ + CDiskTxPos pos(pindex->GetBlockPos(), GetSizeOfCompactSize(block.vtx.size())); + std::vector<std::pair<uint256, CDiskTxPos>> vPos; + vPos.reserve(block.vtx.size()); + for (const auto& tx : block.vtx) { + vPos.emplace_back(tx->GetHash(), pos); + pos.nTxOffset += ::GetSerializeSize(*tx, SER_DISK, CLIENT_VERSION); + } + return m_db->WriteTxs(vPos); +} + +void TxIndex::BlockConnected(const std::shared_ptr<const CBlock>& block, const CBlockIndex* pindex, + const std::vector<CTransactionRef>& txn_conflicted) +{ + if (!m_synced) { + return; + } + + const CBlockIndex* best_block_index = m_best_block_index.load(); + if (!best_block_index) { + if (pindex->nHeight != 0) { + FatalError("%s: First block connected is not the genesis block (height=%d)", + __func__, pindex->nHeight); + return; + } + } else { + // Ensure block connects to an ancestor of the current best block. This should be the case + // most of the time, but may not be immediately after the the sync thread catches up and sets + // m_synced. Consider the case where there is a reorg and the blocks on the stale branch are + // in the ValidationInterface queue backlog even after the sync thread has caught up to the + // new chain tip. In this unlikely event, log a warning and let the queue clear. + if (best_block_index->GetAncestor(pindex->nHeight - 1) != pindex->pprev) { + LogPrintf("%s: WARNING: Block %s does not connect to an ancestor of " /* Continued */ + "known best chain (tip=%s); not updating txindex\n", + __func__, pindex->GetBlockHash().ToString(), + best_block_index->GetBlockHash().ToString()); + return; + } + } + + if (WriteBlock(*block, pindex)) { + m_best_block_index = pindex; + } else { + FatalError("%s: Failed to write block %s to txindex", + __func__, pindex->GetBlockHash().ToString()); + return; + } +} + +void TxIndex::SetBestChain(const CBlockLocator& locator) +{ + if (!m_synced) { + return; + } + + const uint256& locator_tip_hash = locator.vHave.front(); + const CBlockIndex* locator_tip_index; + { + LOCK(cs_main); + locator_tip_index = LookupBlockIndex(locator_tip_hash); + } + + if (!locator_tip_index) { + FatalError("%s: First block (hash=%s) in locator was not found", + __func__, locator_tip_hash.ToString()); + return; + } + + // This checks that SetBestChain callbacks are received after BlockConnected. The check may fail + // immediately after the the sync thread catches up and sets m_synced. Consider the case where + // there is a reorg and the blocks on the stale branch are in the ValidationInterface queue + // backlog even after the sync thread has caught up to the new chain tip. In this unlikely + // event, log a warning and let the queue clear. + const CBlockIndex* best_block_index = m_best_block_index.load(); + if (best_block_index->GetAncestor(locator_tip_index->nHeight) != locator_tip_index) { + LogPrintf("%s: WARNING: Locator contains block (hash=%s) not on known best " /* Continued */ + "chain (tip=%s); not writing txindex locator\n", + __func__, locator_tip_hash.ToString(), + best_block_index->GetBlockHash().ToString()); + return; + } + + if (!m_db->WriteBestBlock(locator)) { + error("%s: Failed to write locator to disk", __func__); + } +} + +bool TxIndex::FindTx(const uint256& txid, CDiskTxPos& pos) const +{ + return m_db->ReadTxPos(txid, pos); +} + +void TxIndex::Start() +{ + // Need to register this ValidationInterface before running Init(), so that + // callbacks are not missed if Init sets m_synced to true. + RegisterValidationInterface(this); + if (!Init()) { + FatalError("%s: txindex failed to initialize", __func__); + return; + } +} + +void TxIndex::Stop() +{ + UnregisterValidationInterface(this); +} diff --git a/src/index/txindex.h b/src/index/txindex.h new file mode 100644 index 0000000000..3d42a89635 --- /dev/null +++ b/src/index/txindex.h @@ -0,0 +1,60 @@ +// Copyright (c) 2017-2018 The Bitcoin Core developers +// Distributed under the MIT software license, see the accompanying +// file COPYING or http://www.opensource.org/licenses/mit-license.php. + +#ifndef BITCOIN_INDEX_TXINDEX_H +#define BITCOIN_INDEX_TXINDEX_H + +#include <primitives/block.h> +#include <txdb.h> +#include <uint256.h> +#include <validationinterface.h> + +class CBlockIndex; + +/** + * TxIndex is used to look up transactions included in the blockchain by hash. + * The index is written to a LevelDB database and records the filesystem + * location of each transaction by transaction hash. + */ +class TxIndex final : public CValidationInterface +{ +private: + const std::unique_ptr<TxIndexDB> m_db; + + /// Whether the index is in sync with the main chain. The flag is flipped + /// from false to true once, after which point this starts processing + /// ValidationInterface notifications to stay in sync. + std::atomic<bool> m_synced; + + /// The last block in the chain that the TxIndex is in sync with. + std::atomic<const CBlockIndex*> m_best_block_index; + + /// Initialize internal state from the database and block index. + bool Init(); + + /// Write update index entries for a newly connected block. + bool WriteBlock(const CBlock& block, const CBlockIndex* pindex); + +protected: + void BlockConnected(const std::shared_ptr<const CBlock>& block, const CBlockIndex* pindex, + const std::vector<CTransactionRef>& txn_conflicted) override; + + void SetBestChain(const CBlockLocator& locator) override; + +public: + /// Constructs the TxIndex, which becomes available to be queried. + explicit TxIndex(std::unique_ptr<TxIndexDB> db); + + /// Look up the on-disk location of a transaction by hash. + bool FindTx(const uint256& txid, CDiskTxPos& pos) const; + + /// Start initializes the sync state and registers the instance as a + /// ValidationInterface so that it stays in sync with blockchain updates. + void Start(); + + /// Stops the instance from staying in sync with blockchain updates. + void Stop(); +}; + +#endif // BITCOIN_INDEX_TXINDEX_H |