git / moonbite-core / src/txmempool.h · raw
// Copyright (c) 2009-2010 Satoshi Nakamoto// Copyright (c) 2009-2020 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_TXMEMPOOL_H#define BITCOIN_TXMEMPOOL_H#include <atomic>#include <map>#include <set>#include <string>#include <utility>#include <vector>#include <amount.h>#include <coins.h>#include <crypto/siphash.h>#include <indirectmap.h>#include <optional.h>#include <policy/feerate.h>#include <primitives/transaction.h>#include <sync.h>#include <random.h>#include <boost/multi_index_container.hpp>#include <boost/multi_index/hashed_index.hpp>#include <boost/multi_index/ordered_index.hpp>#include <boost/multi_index/sequenced_index.hpp>#include <caches/Cache.h>class CBlock;class CBlockIndex;struct DisconnectedBlockTransactions;extern RecursiveMutex cs_main;/** Fake height value used in Coin to signify they are only in the memory pool (since 0.8) */static const uint32_t MEMPOOL_HEIGHT = 0x7FFFFFFF;/** Default size of CMemPool's recentTxsByKernel cache */static const unsigned int DEFAULT_MEMPOOL_MWEB_CACHE_SIZE = 1000;struct LockPoints{ // Will be set to the blockchain height and median time past // values that would be necessary to satisfy all relative locktime // constraints (BIP68) of this tx given our view of block chain history int height; int64_t time; // As long as the current chain descends from the highest height block // containing one of the inputs used in the calculation, then the cached // values are still valid even after a reorg. CBlockIndex* maxInputBlock; LockPoints() : height(0), time(0), maxInputBlock(nullptr) { }};struct CompareIteratorByHash { // SFINAE for T where T is either a pointer type (e.g., a txiter) or a reference_wrapper<T> // (e.g. a wrapped CTxMemPoolEntry&) template <typename T> bool operator()(const std::reference_wrapper<T>& a, const std::reference_wrapper<T>& b) const { return a.get().GetTx().GetHash() < b.get().GetTx().GetHash(); } template <typename T> bool operator()(const T& a, const T& b) const { return a->GetTx().GetHash() < b->GetTx().GetHash(); }};/** \class CTxMemPoolEntry * * CTxMemPoolEntry stores data about the corresponding transaction, as well * as data about all in-mempool transactions that depend on the transaction * ("descendant" transactions). * * When a new entry is added to the mempool, we update the descendant state * (nCountWithDescendants, nSizeWithDescendants, and nModFeesWithDescendants) for * all ancestors of the newly added transaction. * */class CTxMemPoolEntry{public: typedef std::reference_wrapper<const CTxMemPoolEntry> CTxMemPoolEntryRef; // two aliases, should the types ever diverge typedef std::set<CTxMemPoolEntryRef, CompareIteratorByHash> Parents; typedef std::set<CTxMemPoolEntryRef, CompareIteratorByHash> Children;private: const CTransactionRef tx; mutable Parents m_parents; mutable Children m_children; const CAmount nFee; //!< Cached to avoid expensive parent-transaction lookups const size_t nTxWeight; //!< ... and avoid recomputing tx weight (also used for GetTxSize()) const uint64_t mweb_weight; const size_t nUsageSize; //!< ... and total memory usage const int64_t nTime; //!< Local time when entering the mempool const unsigned int entryHeight; //!< Chain height when entering the mempool const bool spendsCoinbase; //!< keep track of transactions that spend a coinbase const int64_t sigOpCost; //!< Total sigop cost int64_t feeDelta; //!< Used for determining the priority of the transaction for mining in a block LockPoints lockPoints; //!< Track the height and time at which tx was final // Information about descendants of this transaction that are in the // mempool; if we remove this transaction we must remove all of these // descendants as well. uint64_t nCountWithDescendants; //!< number of descendant transactions uint64_t nSizeWithDescendants; //!< ... and size CAmount nModFeesWithDescendants; //!< ... and total fees (all including us) uint64_t nMWEBWeightWithDescendants; // Analogous statistics for ancestor transactions uint64_t nCountWithAncestors; uint64_t nSizeWithAncestors; CAmount nModFeesWithAncestors; int64_t nSigOpCostWithAncestors; int64_t nMWEBWeightWithAncestors;public: CTxMemPoolEntry(const CTransactionRef& _tx, const CAmount& _nFee, int64_t _nTime, unsigned int _entryHeight, bool spendsCoinbase, int64_t nSigOpsCost, LockPoints lp); const CTransaction& GetTx() const { return *this->tx; } CTransactionRef GetSharedTx() const { return this->tx; } const CAmount& GetFee() const { return nFee; } size_t GetTxSize() const; size_t GetTxWeight() const { return nTxWeight; } size_t GetMWEBWeight() const { return mweb_weight; } std::chrono::seconds GetTime() const { return std::chrono::seconds{nTime}; } unsigned int GetHeight() const { return entryHeight; } int64_t GetSigOpCost() const { return sigOpCost; } int64_t GetModifiedFee() const { return nFee + feeDelta; } size_t DynamicMemoryUsage() const { return nUsageSize; } const LockPoints& GetLockPoints() const { return lockPoints; } // Adjusts the descendant state. void UpdateDescendantState(int64_t modifySize, CAmount modifyFee, int64_t modifyCount, int64_t modifyMWEBWeight); // Adjusts the ancestor state void UpdateAncestorState(int64_t modifySize, CAmount modifyFee, int64_t modifyCount, int64_t modifySigOps, int64_t modifyMWEBWeight); // Updates the fee delta used for mining priority score, and the // modified fees with descendants. void UpdateFeeDelta(int64_t feeDelta); // Update the LockPoints after a reorg void UpdateLockPoints(const LockPoints& lp); uint64_t GetCountWithDescendants() const { return nCountWithDescendants; } uint64_t GetSizeWithDescendants() const { return nSizeWithDescendants; } CAmount GetModFeesWithDescendants() const { return nModFeesWithDescendants; } uint64_t GetMWEBWeightWithDescendants() const { return nMWEBWeightWithDescendants; } bool GetSpendsCoinbase() const { return spendsCoinbase; } uint64_t GetCountWithAncestors() const { return nCountWithAncestors; } uint64_t GetSizeWithAncestors() const { return nSizeWithAncestors; } CAmount GetModFeesWithAncestors() const { return nModFeesWithAncestors; } int64_t GetSigOpCostWithAncestors() const { return nSigOpCostWithAncestors; } uint64_t GetMWEBWeightWithAncestors() const { return nMWEBWeightWithAncestors; } const Parents& GetMemPoolParentsConst() const { return m_parents; } const Children& GetMemPoolChildrenConst() const { return m_children; } Parents& GetMemPoolParents() const { return m_parents; } Children& GetMemPoolChildren() const { return m_children; } mutable size_t vTxHashesIdx; //!< Index in mempool's vTxHashes mutable uint64_t m_epoch; //!< epoch when last touched, useful for graph algorithms};// Helpers for modifying CTxMemPool::mapTx, which is a boost multi_index.struct update_descendant_state{ update_descendant_state(int64_t _modifySize, CAmount _modifyFee, int64_t _modifyCount, int64_t _modifyMWEBWeight) : modifySize(_modifySize), modifyFee(_modifyFee), modifyCount(_modifyCount), modifyMWEBWeight(_modifyMWEBWeight) {} void operator() (CTxMemPoolEntry &e) { e.UpdateDescendantState(modifySize, modifyFee, modifyCount, modifyMWEBWeight); } private: int64_t modifySize; CAmount modifyFee; int64_t modifyCount; int64_t modifyMWEBWeight;};struct update_ancestor_state{ update_ancestor_state(int64_t _modifySize, CAmount _modifyFee, int64_t _modifyCount, int64_t _modifySigOpsCost, int64_t _modifyMWEBWeight) : modifySize(_modifySize), modifyFee(_modifyFee), modifyCount(_modifyCount), modifySigOpsCost(_modifySigOpsCost), modifyMWEBWeight(_modifyMWEBWeight) {} void operator() (CTxMemPoolEntry &e) { e.UpdateAncestorState(modifySize, modifyFee, modifyCount, modifySigOpsCost, modifyMWEBWeight); } private: int64_t modifySize; CAmount modifyFee; int64_t modifyCount; int64_t modifySigOpsCost; int64_t modifyMWEBWeight;};struct update_fee_delta{ explicit update_fee_delta(int64_t _feeDelta) : feeDelta(_feeDelta) { } void operator() (CTxMemPoolEntry &e) { e.UpdateFeeDelta(feeDelta); }private: int64_t feeDelta;};struct update_lock_points{ explicit update_lock_points(const LockPoints& _lp) : lp(_lp) { } void operator() (CTxMemPoolEntry &e) { e.UpdateLockPoints(lp); }private: const LockPoints& lp;};// extracts a transaction hash from CTxMemPoolEntry or CTransactionRefstruct mempoolentry_txid{ typedef uint256 result_type; result_type operator() (const CTxMemPoolEntry &entry) const { return entry.GetTx().GetHash(); } result_type operator() (const CTransactionRef& tx) const { return tx->GetHash(); }};// extracts a transaction witness-hash from CTxMemPoolEntry or CTransactionRefstruct mempoolentry_wtxid{ typedef uint256 result_type; result_type operator() (const CTxMemPoolEntry &entry) const { return entry.GetTx().GetWitnessHash(); } result_type operator() (const CTransactionRef& tx) const { return tx->GetWitnessHash(); }};/** \class CompareTxMemPoolEntryByDescendantScore * * Sort an entry by max(score/size of entry's tx, score/size with all descendants). */class CompareTxMemPoolEntryByDescendantScore{public: bool operator()(const CTxMemPoolEntry& a, const CTxMemPoolEntry& b) const { double a_mod_fee, a_size, b_mod_fee, b_size; GetModFeeAndSize(a, a_mod_fee, a_size); GetModFeeAndSize(b, b_mod_fee, b_size); // Avoid division by rewriting (a/b > c/d) as (a*d > c*b). double f1 = a_mod_fee * b_size; double f2 = a_size * b_mod_fee; if (f1 == f2) { return a.GetTime() >= b.GetTime(); } return f1 < f2; } // Return the fee/size we're using for sorting this entry. void GetModFeeAndSize(const CTxMemPoolEntry &a, double &mod_fee, double &size) const { // Compare feerate with descendants to feerate of the transaction, and // return the fee/size for the max. double f1 = (double)a.GetModifiedFee() * a.GetSizeWithDescendants(); double f2 = (double)a.GetModFeesWithDescendants() * a.GetTxSize(); if (f2 > f1) { mod_fee = a.GetModFeesWithDescendants(); size = a.GetSizeWithDescendants(); } else { mod_fee = a.GetModifiedFee(); size = a.GetTxSize(); } }};/** \class CompareTxMemPoolEntryByScore * * Sort by feerate of entry (fee/size) in descending order * This is only used for transaction relay, so we use GetFee() * instead of GetModifiedFee() to avoid leaking prioritization * information via the sort order. */class CompareTxMemPoolEntryByScore{public: bool operator()(const CTxMemPoolEntry& a, const CTxMemPoolEntry& b) const { double f1 = (double)a.GetFee() * b.GetTxSize(); double f2 = (double)b.GetFee() * a.GetTxSize(); if (f1 == f2) { return b.GetTx().GetHash() < a.GetTx().GetHash(); } return f1 > f2; }};class CompareTxMemPoolEntryByEntryTime{public: bool operator()(const CTxMemPoolEntry& a, const CTxMemPoolEntry& b) const { return a.GetTime() < b.GetTime(); }};/** \class CompareTxMemPoolEntryByAncestorScore * * Sort an entry by min(score/size of entry's tx, score/size with all ancestors). */class CompareTxMemPoolEntryByAncestorFee{public: template<typename T> bool operator()(const T& a, const T& b) const { double a_mod_fee, a_size, b_mod_fee, b_size; GetModFeeAndSize(a, a_mod_fee, a_size); GetModFeeAndSize(b, b_mod_fee, b_size); // Avoid division by rewriting (a/b > c/d) as (a*d > c*b). double f1 = a_mod_fee * b_size; double f2 = a_size * b_mod_fee; if (f1 == f2) { return a.GetTx().GetHash() < b.GetTx().GetHash(); } return f1 > f2; } // Return the fee/size we're using for sorting this entry. template <typename T> void GetModFeeAndSize(const T &a, double &mod_fee, double &size) const { // Compare feerate with ancestors to feerate of the transaction, and // return the fee/size for the min. double f1 = (double)a.GetModifiedFee() * a.GetSizeWithAncestors(); double f2 = (double)a.GetModFeesWithAncestors() * a.GetTxSize(); if (f1 > f2) { mod_fee = a.GetModFeesWithAncestors(); size = a.GetSizeWithAncestors(); } else { mod_fee = a.GetModifiedFee(); size = a.GetTxSize(); } }};// Multi_index tag namesstruct descendant_score {};struct entry_time {};struct ancestor_score {};struct index_by_wtxid {};class CBlockPolicyEstimator;/** * Information about a mempool transaction. */struct TxMempoolInfo{ /** The transaction itself */ CTransactionRef tx; /** Time the transaction entered the mempool. */ std::chrono::seconds m_time; /** Fee of the transaction. */ CAmount fee; /** Virtual size of the transaction. */ size_t vsize; /** MWEB weight */ uint64_t mweb_weight; /** The fee delta. */ int64_t nFeeDelta;};/** Reason why a transaction was removed from the mempool, * this is passed to the notification signal. */enum class MemPoolRemovalReason { EXPIRY, //!< Expired from mempool SIZELIMIT, //!< Removed in size limiting REORG, //!< Removed for reorganization BLOCK, //!< Removed for block CONFLICT, //!< Removed for conflict with in-block transaction REPLACED, //!< Removed for replacement};class SaltedTxidHasher{private: /** Salt */ const uint64_t k0, k1;public: SaltedTxidHasher(); size_t operator()(const uint256& txid) const { return SipHashUint256(k0, k1, txid); }};/** * CTxMemPool stores valid-according-to-the-current-best-chain transactions * that may be included in the next block. * * Transactions are added when they are seen on the network (or created by the * local node), but not all transactions seen are added to the pool. For * example, the following new transactions will not be added to the mempool: * - a transaction which doesn't meet the minimum fee requirements. * - a new transaction that double-spends an input of a transaction already in * the pool where the new transaction does not meet the Replace-By-Fee * requirements as defined in BIP 125. * - a non-standard transaction. * * CTxMemPool::mapTx, and CTxMemPoolEntry bookkeeping: * * mapTx is a boost::multi_index that sorts the mempool on 5 criteria: * - transaction hash (txid) * - witness-transaction hash (wtxid) * - descendant feerate [we use max(feerate of tx, feerate of tx with all descendants)] * - time in mempool * - ancestor feerate [we use min(feerate of tx, feerate of tx with all unconfirmed ancestors)] * * Note: the term "descendant" refers to in-mempool transactions that depend on * this one, while "ancestor" refers to in-mempool transactions that a given * transaction depends on. * * In order for the feerate sort to remain correct, we must update transactions * in the mempool when new descendants arrive. To facilitate this, we track * the set of in-mempool direct parents and direct children in mapLinks. Within * each CTxMemPoolEntry, we track the size and fees of all descendants. * * Usually when a new transaction is added to the mempool, it has no in-mempool * children (because any such children would be an orphan). So in * addUnchecked(), we: * - update a new entry's setMemPoolParents to include all in-mempool parents * - update the new entry's direct parents to include the new tx as a child * - update all ancestors of the transaction to include the new tx's size/fee * * When a transaction is removed from the mempool, we must: * - update all in-mempool parents to not track the tx in setMemPoolChildren * - update all ancestors to not include the tx's size/fees in descendant state * - update all in-mempool children to not include it as a parent * * These happen in UpdateForRemoveFromMempool(). (Note that when removing a * transaction along with its descendants, we must calculate that set of * transactions to be removed before doing the removal, or else the mempool can * be in an inconsistent state where it's impossible to walk the ancestors of * a transaction.) * * In the event of a reorg, the assumption that a newly added tx has no * in-mempool children is false. In particular, the mempool is in an * inconsistent state while new transactions are being added, because there may * be descendant transactions of a tx coming from a disconnected block that are * unreachable from just looking at transactions in the mempool (the linking * transactions may also be in the disconnected block, waiting to be added). * Because of this, there's not much benefit in trying to search for in-mempool * children in addUnchecked(). Instead, in the special case of transactions * being added from a disconnected block, we require the caller to clean up the * state, to account for in-mempool, out-of-block descendants for all the * in-block transactions by calling UpdateTransactionsFromBlock(). Note that * until this is called, the mempool state is not consistent, and in particular * mapLinks may not be correct (and therefore functions like * CalculateMemPoolAncestors() and CalculateDescendants() that rely * on them to walk the mempool are not generally safe to use). * * Computational limits: * * Updating all in-mempool ancestors of a newly added transaction can be slow, * if no bound exists on how many in-mempool ancestors there may be. * CalculateMemPoolAncestors() takes configurable limits that are designed to * prevent these calculations from being too CPU intensive. * */class CTxMemPool{private: uint32_t nCheckFrequency GUARDED_BY(cs); //!< Value n means that n times in 2^32 we check. std::atomic<unsigned int> nTransactionsUpdated; //!< Used by getblocktemplate to trigger CreateNewBlock() invocation CBlockPolicyEstimator* minerPolicyEstimator; uint64_t totalTxSize; //!< sum of all mempool tx's virtual sizes. Differs from serialized tx size since witness data is discounted. Defined in BIP 141. uint64_t cachedInnerUsage; //!< sum of dynamic memory usage of all the map elements (NOT the maps themselves) mutable int64_t lastRollingFeeUpdate; mutable bool blockSinceLastRollingFeeBump; mutable double rollingMinimumFeeRate; //!< minimum fee to get into the pool, decreases exponentially mutable uint64_t m_epoch; mutable bool m_has_epoch_guard; // In-memory counter for external mempool tracking purposes. // This number is incremented once every time a transaction // is added or removed from the mempool for any reason. mutable uint64_t m_sequence_number{1}; void trackPackageRemoved(const CFeeRate& rate) EXCLUSIVE_LOCKS_REQUIRED(cs); bool m_is_loaded GUARDED_BY(cs){false};public: static const int ROLLING_FEE_HALFLIFE = 60 * 60 * 12; // public only for testing typedef boost::multi_index_container< CTxMemPoolEntry, boost::multi_index::indexed_by< // sorted by txid boost::multi_index::hashed_unique<mempoolentry_txid, SaltedTxidHasher>, // sorted by wtxid boost::multi_index::hashed_unique< boost::multi_index::tag<index_by_wtxid>, mempoolentry_wtxid, SaltedTxidHasher >, // sorted by fee rate boost::multi_index::ordered_non_unique< boost::multi_index::tag<descendant_score>, boost::multi_index::identity<CTxMemPoolEntry>, CompareTxMemPoolEntryByDescendantScore >, // sorted by entry time boost::multi_index::ordered_non_unique< boost::multi_index::tag<entry_time>, boost::multi_index::identity<CTxMemPoolEntry>, CompareTxMemPoolEntryByEntryTime >, // sorted by fee rate with ancestors boost::multi_index::ordered_non_unique< boost::multi_index::tag<ancestor_score>, boost::multi_index::identity<CTxMemPoolEntry>, CompareTxMemPoolEntryByAncestorFee > > > indexed_transaction_set; /** * This mutex needs to be locked when accessing `mapTx` or other members * that are guarded by it. * * @par Consistency guarantees * * By design, it is guaranteed that: * * 1. Locking both `cs_main` and `mempool.cs` will give a view of mempool * that is consistent with current chain tip (`::ChainActive()` and * `CoinsTip()`) and is fully populated. Fully populated means that if the * current active chain is missing transactions that were present in a * previously active chain, all the missing transactions will have been * re-added to the mempool and should be present if they meet size and * consistency constraints. * * 2. Locking `mempool.cs` without `cs_main` will give a view of a mempool * consistent with some chain that was active since `cs_main` was last * locked, and that is fully populated as described above. It is ok for * code that only needs to query or remove transactions from the mempool * to lock just `mempool.cs` without `cs_main`. * * To provide these guarantees, it is necessary to lock both `cs_main` and * `mempool.cs` whenever adding transactions to the mempool and whenever * changing the chain tip. It's necessary to keep both mutexes locked until * the mempool is consistent with the new chain tip and fully populated. */ mutable RecursiveMutex cs; indexed_transaction_set mapTx GUARDED_BY(cs); using txiter = indexed_transaction_set::nth_index<0>::type::const_iterator; std::vector<std::pair<uint256, txiter>> vTxHashes GUARDED_BY(cs); //!< All tx witness hashes/entries in mapTx, in random order typedef std::set<txiter, CompareIteratorByHash> setEntries; uint64_t CalculateDescendantMaximum(txiter entry) const EXCLUSIVE_LOCKS_REQUIRED(cs);private: typedef std::map<txiter, setEntries, CompareIteratorByHash> cacheMap; void UpdateParent(txiter entry, txiter parent, bool add) EXCLUSIVE_LOCKS_REQUIRED(cs); void UpdateChild(txiter entry, txiter child, bool add) EXCLUSIVE_LOCKS_REQUIRED(cs); std::vector<indexed_transaction_set::const_iterator> GetSortedDepthAndScore() const EXCLUSIVE_LOCKS_REQUIRED(cs); /** * Track locally submitted transactions to periodically retry initial broadcast. */ std::set<uint256> m_unbroadcast_txids GUARDED_BY(cs);public: /** * Maps outputs to mempool transactions that spend them. */ std::map<OutputIndex, const CTransaction*> mapNextTx GUARDED_BY(cs); /** * Maps MWEB output IDs to mempool transactions that create them. */ std::map<mw::Hash, const CTransaction*> mapTxOutputs_MWEB GUARDED_BY(cs); /** * FIFO cache of txs recently removed from the mempool keyed by kernel ID. */ FIFOCache<mw::Hash, CTransactionRef> recentTxsByKernel GUARDED_BY(cs){DEFAULT_MEMPOOL_MWEB_CACHE_SIZE}; std::map<uint256, CAmount> mapDeltas; /** Create a new CTxMemPool. */ explicit CTxMemPool(CBlockPolicyEstimator* estimator = nullptr); /** * If sanity-checking is turned on, check makes sure the pool is * consistent (does not contain two transactions that spend the same inputs, * all inputs are in the mapNextTx array). If sanity-checking is turned off, * check does nothing. */ void check(const CCoinsViewCache *pcoins) const; void setSanityCheck(double dFrequency = 1.0) { LOCK(cs); nCheckFrequency = static_cast<uint32_t>(dFrequency * 4294967295.0); } // addUnchecked must updated state for all ancestors of a given transaction, // to track size/count of descendant transactions. First version of // addUnchecked can be used to have it call CalculateMemPoolAncestors(), and // then invoke the second version. // Note that addUnchecked is ONLY called from ATMP outside of tests // and any other callers may break wallet's in-mempool tracking (due to // lack of CValidationInterface::TransactionAddedToMempool callbacks). void addUnchecked(const CTxMemPoolEntry& entry, bool validFeeEstimate = true) EXCLUSIVE_LOCKS_REQUIRED(cs, cs_main); void addUnchecked(const CTxMemPoolEntry& entry, setEntries& setAncestors, bool validFeeEstimate = true) EXCLUSIVE_LOCKS_REQUIRED(cs, cs_main); void removeRecursive(const CTransaction& tx, MemPoolRemovalReason reason) EXCLUSIVE_LOCKS_REQUIRED(cs); void removeForReorg(const CCoinsViewCache* pcoins, unsigned int nMemPoolHeight, int flags) EXCLUSIVE_LOCKS_REQUIRED(cs, cs_main); void removeConflicts(const CTransaction& tx) EXCLUSIVE_LOCKS_REQUIRED(cs); void removeForBlock(const CBlock& block, unsigned int nBlockHeight, DisconnectedBlockTransactions* disconnectpool) EXCLUSIVE_LOCKS_REQUIRED(cs); void clear(); void _clear() EXCLUSIVE_LOCKS_REQUIRED(cs); //lock free bool CompareDepthAndScore(const uint256& hasha, const uint256& hashb, bool wtxid=false); void queryHashes(std::vector<uint256>& vtxid) const; bool isSpent(const OutputIndex& outpoint) const; unsigned int GetTransactionsUpdated() const; void AddTransactionsUpdated(unsigned int n); /** * Check that none of this transactions inputs are in the mempool, and thus * the tx is not dependent on other mempool transactions to be included in a block. */ bool HasNoInputsOf(const CTransaction& tx) const EXCLUSIVE_LOCKS_REQUIRED(cs); /** Affect CreateNewBlock prioritisation of transactions */ void PrioritiseTransaction(const uint256& hash, const CAmount& nFeeDelta); void ApplyDelta(const uint256& hash, CAmount &nFeeDelta) const EXCLUSIVE_LOCKS_REQUIRED(cs); void ClearPrioritisation(const uint256& hash) EXCLUSIVE_LOCKS_REQUIRED(cs); /** Get the transaction in the pool that spends the same prevout */ const CTransaction* GetConflictTx(const OutputIndex& prevout) const EXCLUSIVE_LOCKS_REQUIRED(cs); /** Returns an iterator to the given hash, if found */ Optional<txiter> GetIter(const uint256& txid) const EXCLUSIVE_LOCKS_REQUIRED(cs); /** Returns an iterator to the transaction the input spends from, if found */ Optional<txiter> GetIter(const CTxInput& input) const EXCLUSIVE_LOCKS_REQUIRED(cs); /** Translate a set of hashes into a set of pool iterators to avoid repeated lookups */ setEntries GetIterSet(const std::set<uint256>& hashes) const EXCLUSIVE_LOCKS_REQUIRED(cs); /** Remove a set of transactions from the mempool. * If a transaction is in this set, then all in-mempool descendants must * also be in the set, unless this transaction is being removed for being * in a block. * Set updateDescendants to true when removing a tx that was in a block, so * that any in-mempool descendants have their ancestor state updated. */ void RemoveStaged(setEntries& stage, bool updateDescendants, MemPoolRemovalReason reason) EXCLUSIVE_LOCKS_REQUIRED(cs); /** When adding transactions from a disconnected block back to the mempool, * new mempool entries may have children in the mempool (which is generally * not the case when otherwise adding transactions). * UpdateTransactionsFromBlock() will find child transactions and update the * descendant state for each transaction in vHashesToUpdate (excluding any * child transactions present in vHashesToUpdate, which are already accounted * for). Note: vHashesToUpdate should be the set of transactions from the * disconnected block that have been accepted back into the mempool. */ void UpdateTransactionsFromBlock(const std::vector<uint256>& vHashesToUpdate) EXCLUSIVE_LOCKS_REQUIRED(cs, cs_main); /** Try to calculate all in-mempool ancestors of entry. * (these are all calculated including the tx itself) * limitAncestorCount = max number of ancestors * limitAncestorSize = max size of ancestors * limitDescendantCount = max number of descendants any ancestor can have * limitDescendantSize = max size of descendants any ancestor can have * errString = populated with error reason if any limits are hit * fSearchForParents = whether to search a tx's vin for in-mempool parents, or * look up parents from mapLinks. Must be true for entries not in the mempool */ bool CalculateMemPoolAncestors(const CTxMemPoolEntry& entry, setEntries& setAncestors, uint64_t limitAncestorCount, uint64_t limitAncestorSize, uint64_t limitDescendantCount, uint64_t limitDescendantSize, std::string& errString, bool fSearchForParents = true) const EXCLUSIVE_LOCKS_REQUIRED(cs); /** Populate setDescendants with all in-mempool descendants of hash. * Assumes that setDescendants includes all in-mempool descendants of anything * already in it. */ void CalculateDescendants(txiter it, setEntries& setDescendants) const EXCLUSIVE_LOCKS_REQUIRED(cs); /** The minimum fee to get into the mempool, which may itself not be enough * for larger-sized transactions. * The incrementalRelayFee policy variable is used to bound the time it * takes the fee rate to go back down all the way to 0. When the feerate * would otherwise be half of this, it is set to 0 instead. */ CFeeRate GetMinFee(size_t sizelimit) const; /** Remove transactions from the mempool until its dynamic size is <= sizelimit. * pvNoSpendsRemaining, if set, will be populated with the list of outpoints * which are not in mempool which no longer have any spends in this mempool. */ void TrimToSize(size_t sizelimit, std::vector<COutPoint>* pvNoSpendsRemaining = nullptr) EXCLUSIVE_LOCKS_REQUIRED(cs); /** Expire all transaction (and their dependencies) in the mempool older than time. Return the number of removed transactions. */ int Expire(std::chrono::seconds time) EXCLUSIVE_LOCKS_REQUIRED(cs); /** * Calculate the ancestor and descendant count for the given transaction. * The counts include the transaction itself. */ void GetTransactionAncestry(const uint256& txid, size_t& ancestors, size_t& descendants) const; /** @returns true if the mempool is fully loaded */ bool IsLoaded() const; /** Sets the current loaded state */ void SetIsLoaded(bool loaded); unsigned long size() const { LOCK(cs); return mapTx.size(); } uint64_t GetTotalTxSize() const EXCLUSIVE_LOCKS_REQUIRED(cs) { AssertLockHeld(cs); return totalTxSize; } bool exists(const GenTxid& gtxid) const { LOCK(cs); if (gtxid.IsWtxid()) { return (mapTx.get<index_by_wtxid>().count(gtxid.GetHash()) != 0); } return (mapTx.count(gtxid.GetHash()) != 0); } bool exists(const uint256& txid) const { return exists(GenTxid{false, txid}); } bool GetCreatedTx(const mw::Hash& output_id, uint256& hash) const { LOCK(cs); auto iter = mapTxOutputs_MWEB.find(output_id); if (iter != mapTxOutputs_MWEB.end()) { hash = iter->second->GetHash(); return true; } return false; } CTransactionRef get(const uint256& hash) const; txiter get_iter_from_wtxid(const uint256& wtxid) const EXCLUSIVE_LOCKS_REQUIRED(cs) { AssertLockHeld(cs); return mapTx.project<0>(mapTx.get<index_by_wtxid>().find(wtxid)); } TxMempoolInfo info(const uint256& hash) const; TxMempoolInfo info(const GenTxid& gtxid) const; std::vector<TxMempoolInfo> infoAll() const; size_t DynamicMemoryUsage() const; /** Adds a transaction to the unbroadcast set */ void AddUnbroadcastTx(const uint256& txid) { LOCK(cs); // Sanity check the transaction is in the mempool & insert into // unbroadcast set. if (exists(txid)) m_unbroadcast_txids.insert(txid); }; /** Removes a transaction from the unbroadcast set */ void RemoveUnbroadcastTx(const uint256& txid, const bool unchecked = false); /** Returns transactions in unbroadcast set */ std::set<uint256> GetUnbroadcastTxs() const { LOCK(cs); return m_unbroadcast_txids; } /** Returns whether a txid is in the unbroadcast set */ bool IsUnbroadcastTx(const uint256& txid) const EXCLUSIVE_LOCKS_REQUIRED(cs) { AssertLockHeld(cs); return m_unbroadcast_txids.count(txid) != 0; } /** Guards this internal counter for external reporting */ uint64_t GetAndIncrementSequence() const EXCLUSIVE_LOCKS_REQUIRED(cs) { return m_sequence_number++; } uint64_t GetSequence() const EXCLUSIVE_LOCKS_REQUIRED(cs) { return m_sequence_number; }private: /** UpdateForDescendants is used by UpdateTransactionsFromBlock to update * the descendants for a single transaction that has been added to the * mempool but may have child transactions in the mempool, eg during a * chain reorg. setExclude is the set of descendant transactions in the * mempool that must not be accounted for (because any descendants in * setExclude were added to the mempool after the transaction being * updated and hence their state is already reflected in the parent * state). * * cachedDescendants will be updated with the descendants of the transaction * being updated, so that future invocations don't need to walk the * same transaction again, if encountered in another transaction chain. */ void UpdateForDescendants(txiter updateIt, cacheMap &cachedDescendants, const std::set<uint256> &setExclude) EXCLUSIVE_LOCKS_REQUIRED(cs); /** Update ancestors of hash to add/remove it as a descendant transaction. */ void UpdateAncestorsOf(bool add, txiter hash, setEntries &setAncestors) EXCLUSIVE_LOCKS_REQUIRED(cs); /** Set ancestor state for an entry */ void UpdateEntryForAncestors(txiter it, const setEntries &setAncestors) EXCLUSIVE_LOCKS_REQUIRED(cs); /** For each transaction being removed, update ancestors and any direct children. * If updateDescendants is true, then also update in-mempool descendants' * ancestor state. */ void UpdateForRemoveFromMempool(const setEntries &entriesToRemove, bool updateDescendants) EXCLUSIVE_LOCKS_REQUIRED(cs); /** Sever link between specified transaction and direct children. */ void UpdateChildrenForRemoval(txiter entry) EXCLUSIVE_LOCKS_REQUIRED(cs); /** Before calling removeUnchecked for a given transaction, * UpdateForRemoveFromMempool must be called on the entire (dependent) set * of transactions being removed at the same time. We use each * CTxMemPoolEntry's setMemPoolParents in order to walk ancestors of a * given transaction that is removed, so we can't remove intermediate * transactions in a chain before we've updated all the state for the * removal. */ void removeUnchecked(txiter entry, MemPoolRemovalReason reason) EXCLUSIVE_LOCKS_REQUIRED(cs);public: /** EpochGuard: RAII-style guard for using epoch-based graph traversal algorithms. * When walking ancestors or descendants, we generally want to avoid * visiting the same transactions twice. Some traversal algorithms use * std::set (or setEntries) to deduplicate the transaction we visit. * However, use of std::set is algorithmically undesirable because it both * adds an asymptotic factor of O(log n) to traverals cost and triggers O(n) * more dynamic memory allocations. * In many algorithms we can replace std::set with an internal mempool * counter to track the time (or, "epoch") that we began a traversal, and * check + update a per-transaction epoch for each transaction we look at to * determine if that transaction has not yet been visited during the current * traversal's epoch. * Algorithms using std::set can be replaced on a one by one basis. * Both techniques are not fundamentally incompatible across the codebase. * Generally speaking, however, the remaining use of std::set for mempool * traversal should be viewed as a TODO for replacement with an epoch based * traversal, rather than a preference for std::set over epochs in that * algorithm. */ class EpochGuard { const CTxMemPool& pool; public: EpochGuard(const CTxMemPool& in); ~EpochGuard(); }; // N.B. GetFreshEpoch modifies mutable state via the EpochGuard construction // (and later destruction) EpochGuard GetFreshEpoch() const EXCLUSIVE_LOCKS_REQUIRED(cs); /** visited marks a CTxMemPoolEntry as having been traversed * during the lifetime of the most recently created EpochGuard * and returns false if we are the first visitor, true otherwise. * * An EpochGuard must be held when visited is called or an assert will be * triggered. * */ bool visited(txiter it) const EXCLUSIVE_LOCKS_REQUIRED(cs) { assert(m_has_epoch_guard); bool ret = it->m_epoch >= m_epoch; it->m_epoch = std::max(it->m_epoch, m_epoch); return ret; } bool visited(Optional<txiter> it) const EXCLUSIVE_LOCKS_REQUIRED(cs) { assert(m_has_epoch_guard); return !it || visited(*it); }};/** * CCoinsView that brings transactions from a mempool into view. * It does not check for spendings by memory pool transactions. * Instead, it provides access to all Coins which are either unspent in the * base CCoinsView, or are outputs from any mempool transaction! * This allows transaction replacement to work as expected, as you want to * have all inputs "available" to check signatures, and any cycles in the * dependency graph are checked directly in AcceptToMemoryPool. * It also allows you to sign a double-spend directly in * signrawtransactionwithkey and signrawtransactionwithwallet, * as long as the conflicting transaction is not yet confirmed. */class CCoinsViewMemPool : public CCoinsViewBacked{protected: const CTxMemPool& mempool;public: CCoinsViewMemPool(CCoinsView* baseIn, const CTxMemPool& mempoolIn); bool GetCoin(const COutPoint &outpoint, Coin &coin) const override; bool HaveCoin(const OutputIndex& index) const override; bool GetMWEBCoin(const mw::Hash& output_id, Output& coin) const override;};/** * DisconnectedBlockTransactions * During the reorg, it's desirable to re-add previously confirmed transactions * to the mempool, so that anything not re-confirmed in the new chain is * available to be mined. However, it's more efficient to wait until the reorg * is complete and process all still-unconfirmed transactions at that time, * since we expect most confirmed transactions to (typically) still be * confirmed in the new chain, and re-accepting to the memory pool is expensive * (and therefore better to not do in the middle of reorg-processing). * Instead, store the disconnected transactions (in order!) as we go, remove any * that are included in blocks in the new chain, and then process the remaining * still-unconfirmed transactions at the end. */// multi_index tag namesstruct txid_index {};struct insertion_order {};struct DisconnectedBlockTransactions { typedef boost::multi_index_container< CTransactionRef, boost::multi_index::indexed_by< // sorted by txid boost::multi_index::hashed_unique< boost::multi_index::tag<txid_index>, mempoolentry_txid, SaltedTxidHasher >, // sorted by order in the blockchain boost::multi_index::sequenced< boost::multi_index::tag<insertion_order> > > > indexed_disconnected_transactions; // It's almost certainly a logic bug if we don't clear out queuedTx before // destruction, as we add to it while disconnecting blocks, and then we // need to re-process remaining transactions to ensure mempool consistency. // For now, assert() that we've emptied out this object on destruction. // This assert() can always be removed if the reorg-processing code were // to be refactored such that this assumption is no longer true (for // instance if there was some other way we cleaned up the mempool after a // reorg, besides draining this object). ~DisconnectedBlockTransactions() { assert(queuedTx.empty()); } indexed_disconnected_transactions queuedTx; uint64_t cachedInnerUsage = 0; // Estimate the overhead of queuedTx to be 6 pointers + an allocation, as // no exact formula for boost::multi_index_contained is implemented. size_t DynamicMemoryUsage() const { return memusage::MallocUsage(sizeof(CTransactionRef) + 6 * sizeof(void*)) * queuedTx.size() + cachedInnerUsage; } void addTransaction(const CTransactionRef& tx) { if (queuedTx.find(tx->GetHash()) == queuedTx.end()) { queuedTx.insert(tx); cachedInnerUsage += RecursiveDynamicUsage(tx); } } // Remove entries based on txid_index, and update memory usage. void removeForBlock(const std::vector<CTransactionRef>& vtx) { // Short-circuit in the common case of a block being added to the tip if (queuedTx.empty()) { return; } for (auto const &tx : vtx) { auto it = queuedTx.find(tx->GetHash()); if (it != queuedTx.end()) { cachedInnerUsage -= RecursiveDynamicUsage(*it); queuedTx.erase(it); } } } // Remove an entry by insertion_order index, and update memory usage. void removeEntry(indexed_disconnected_transactions::index<insertion_order>::type::iterator entry) { cachedInnerUsage -= RecursiveDynamicUsage(*entry); queuedTx.get<insertion_order>().erase(entry); } void clear() { cachedInnerUsage = 0; queuedTx.clear(); }};#endif // BITCOIN_TXMEMPOOL_H