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1// Copyright (c) 2022-present The Bitcoin Core developers
2// Distributed under the MIT software license, see the accompanying
3// file COPYING or http://www.opensource.org/licenses/mit-license.php.
4
5#ifndef BITCOIN_NODE_MINI_MINER_H
6#define BITCOIN_NODE_MINI_MINER_H
7
8#include <attributes.h>
9#include <consensus/amount.h>
10#include <primitives/transaction.h>
11
12#include <cstdint>
13#include <map>
14#include <optional>
15#include <set>
16#include <vector>
17
18class CFeeRate;
19class CTxMemPool;
20
21namespace node {
22
23// Container for tracking updates to ancestor feerate as we include ancestors in the "block"
24class MiniMinerMempoolEntry
25{
26    const CTransactionRef tx;
27    const int64_t vsize_individual;
28    int64_t vsize_with_ancestors;
29    const CAmount fee_individual;
30    CAmount fee_with_ancestors;
31
32// This class must be constructed while holding mempool.cs. After construction, the object's
33// methods can be called without holding that lock.
34
35public:
36    explicit MiniMinerMempoolEntry(const CTransactionRef& tx_in,
37                                   int64_t vsize_self,
38                                   int64_t vsize_ancestor,
39                                   CAmount fee_self,
40                                   CAmount fee_ancestor):
41        tx{tx_in},
42        vsize_individual{vsize_self},
43        vsize_with_ancestors{vsize_ancestor},
44        fee_individual{fee_self},
45        fee_with_ancestors{fee_ancestor}
46    { }
47
48    CAmount GetModifiedFee() const { return fee_individual; }
49    CAmount GetModFeesWithAncestors() const { return fee_with_ancestors; }
50    int64_t GetTxSize() const { return vsize_individual; }
51    int64_t GetSizeWithAncestors() const { return vsize_with_ancestors; }
52    const CTransaction& GetTx() const LIFETIMEBOUND { return *tx; }
53    void UpdateAncestorState(int64_t vsize_change, CAmount fee_change) {
54        vsize_with_ancestors += vsize_change;
55        fee_with_ancestors += fee_change;
56    }
57};
58
59// Comparator needed for std::set<MockEntryMap::iterator>
60struct IteratorComparator
61{
62    template<typename I>
63    bool operator()(const I& a, const I& b) const
64    {
65        return a->first < b->first;
66    }
67};
68
69/** A minimal version of BlockAssembler, using the same ancestor set scoring algorithm. Allows us to
70 * run this algorithm on a limited set of transactions (e.g. subset of mempool or transactions that
71 * are not yet in mempool) instead of the entire mempool, ignoring consensus rules.
72 * Callers may use this to:
73 * - Calculate the "bump fee" needed to spend an unconfirmed UTXO at a given feerate
74 * - "Linearize" a list of transactions to see the order in which they would be selected for
75 *   inclusion in a block
76 */
77class MiniMiner
78{
79    // When true, a caller may use CalculateBumpFees(). Becomes false if we failed to retrieve
80    // mempool entries (i.e. cluster size too large) or bump fees have already been calculated.
81    bool m_ready_to_calculate{true};
82
83    // Set once per lifetime, fill in during initialization.
84    // txids of to-be-replaced transactions
85    std::set<Txid> m_to_be_replaced;
86
87    // If multiple argument outpoints correspond to the same transaction, cache them together in
88    // a single entry indexed by txid. Then we can just work with txids since all outpoints from
89    // the same tx will have the same bumpfee. Excludes non-mempool transactions.
90    std::map<Txid, std::vector<COutPoint>> m_requested_outpoints_by_txid;
91
92    // Txid to a number representing the order in which this transaction was included (smaller
93    // number = included earlier).  Transactions included in an ancestor set together have the same
94    // sequence number.
95    std::map<Txid, uint32_t> m_inclusion_order;
96    // What we're trying to calculate. Outpoint to the fee needed to bring the transaction to the target feerate.
97    std::map<COutPoint, CAmount> m_bump_fees;
98
99    // The constructed block template
100    std::set<Txid> m_in_block;
101
102    // Information on the current status of the block
103    CAmount m_total_fees{0};
104    int32_t m_total_vsize{0};
105
106    /** Main data structure holding the entries, can be indexed by txid */
107    std::map<Txid, MiniMinerMempoolEntry> m_entries_by_txid;
108    using MockEntryMap = decltype(m_entries_by_txid);
109
110    /** Vector of entries, can be sorted by ancestor feerate. */
111    std::vector<MockEntryMap::iterator> m_entries;
112
113    /** Map of txid to its descendants. Should be inclusive. */
114    std::map<Txid, std::vector<MockEntryMap::iterator>> m_descendant_set_by_txid;
115
116    /** Consider this ancestor package "mined" so remove all these entries from our data structures. */
117    void DeleteAncestorPackage(const std::set<MockEntryMap::iterator, IteratorComparator>& ancestors);
118
119    /** Perform some checks. */
120    void SanityCheck() const;
121
122public:
123    /** Returns true if CalculateBumpFees may be called, false if not. */
124    bool IsReadyToCalculate() const { return m_ready_to_calculate; }
125
126    /** Build a block template until the target feerate is hit. If target_feerate is not given,
127     * builds a block template until all transactions have been selected. */
128    void BuildMockTemplate(std::optional<CFeeRate> target_feerate);
129
130    /** Returns set of txids in the block template if one has been constructed. */
131    std::set<Txid> GetMockTemplateTxids() const { return m_in_block; }
132
133    /** Constructor that takes a list of outpoints that may or may not belong to transactions in the
134     * mempool. Copies out information about the relevant transactions in the mempool into
135     * MiniMinerMempoolEntrys.
136    */
137    MiniMiner(const CTxMemPool& mempool, const std::vector<COutPoint>& outpoints);
138
139    /** Constructor in which the MiniMinerMempoolEntry entries have been constructed manually.
140     * It is assumed that all entries are unique and their values are correct, otherwise results
141     * computed by MiniMiner may be incorrect. Callers should check IsReadyToCalculate() after
142     * construction.
143     * @param[in] descendant_caches A map from each transaction to the set of txids of this
144     *                              transaction's descendant set, including itself. Each tx in
145     *                              manual_entries must have a corresponding entry in this map, and
146     *                              all of the txids in a descendant set must correspond to a tx in
147     *                              manual_entries.
148     */
149    MiniMiner(const std::vector<MiniMinerMempoolEntry>& manual_entries,
150              const std::map<Txid, std::set<Txid>>& descendant_caches);
151
152    /** Construct a new block template and, for each outpoint corresponding to a transaction that
153     * did not make it into the block, calculate the cost of bumping those transactions (and their
154     * ancestors) to the minimum feerate. Returns a map from outpoint to bump fee, or an empty map
155     * if they cannot be calculated. */
156    std::map<COutPoint, CAmount> CalculateBumpFees(const CFeeRate& target_feerate);
157
158    /** Construct a new block template and, calculate the cost of bumping all transactions that did
159     * not make it into the block to the target feerate. Returns the total bump fee, or std::nullopt
160     * if it cannot be calculated. */
161    std::optional<CAmount> CalculateTotalBumpFees(const CFeeRate& target_feerate);
162
163    /** Construct a new block template with all of the transactions and calculate the order in which
164     * they are selected. Returns the sequence number (lower = selected earlier) with which each
165     * transaction was selected, indexed by txid, or an empty map if it cannot be calculated.
166     */
167    std::map<Txid, uint32_t> Linearize();
168};
169} // namespace node
170
171#endif // BITCOIN_NODE_MINI_MINER_H
172

src/wallet/receive.cpp

src/wallet/coinselection.cpp

src/consensus/validation.h

src/primitives/transaction.cpp

src/script/descriptor.cpp

src/bitcoin-cli.cpp

src/rpc/blockchain.cpp

src/rpc/rawtransaction.cpp

src/init.cpp

src/crypto/sha256.cpp

src/consensus/merkle.h

src/consensus/tx_check.h

src/consensus/tx_verify.h

src/policy/feerate.h

src/policy/feerate.cpp

src/primitives/transaction_identifier.h

src/chainparamsbase.h

src/chainparamsbase.cpp

src/util/moneystr.cpp

src/crypto/ripemd160.h

src/crypto/sha1.h

src/crypto/sha512.h

src/crypto/hmac_sha256.h

src/crypto/hmac_sha512.h

src/crypto/hmac_sha256.cpp

src/crypto/hmac_sha512.cpp

src/crypto/hkdf_sha256_32.h

src/crypto/hkdf_sha256_32.cpp

src/support/cleanse.h

src/support/cleanse.cpp

src/crypto/siphash.cpp

src/crypto/muhash.h

src/crypto/chacha20.h

src/crypto/poly1305.h

src/crypto/chacha20poly1305.h

src/crypto/chacha20poly1305.cpp

src/util/chaintype.cpp

src/util/obfuscation.h

src/util/byte_units.h

src/util/overflow.h

src/blockencodings.cpp

src/net_permissions.cpp

src/policy/packages.cpp

src/policy/rbf.cpp

src/policy/truc_policy.cpp

src/policy/ephemeral_policy.cpp

src/policy/settings.cpp

src/policy/policy.cpp

src/node/transaction.cpp

src/node/coin.cpp

src/rpc/client.cpp

src/rpc/external_signer.cpp

src/rpc/request.cpp

src/rpc/server_util.cpp

src/rpc/fees.cpp

src/rpc/output_script.cpp

src/rpc/rawtransaction_util.cpp

src/rpc/rawtransaction_util.h

src/rpc/register.h

src/rpc/request.h

src/rpc/server_util.h

src/rpc/protocol.h

src/rpc/server.h

src/rpc/signmessage.cpp

src/rpc/txoutproof.cpp

src/rpc/util.cpp

src/rpc/util.h

src/wallet/rpc/addresses.cpp

src/wallet/rpc/backup.cpp

src/wallet/rpc/coins.cpp

src/wallet/rpc/encrypt.cpp

src/wallet/rpc/signmessage.cpp

src/wallet/rpc/util.cpp

src/wallet/rpc/util.h

src/wallet/coincontrol.cpp

src/wallet/coincontrol.h

src/wallet/context.cpp

src/wallet/context.h

src/wallet/crypter.cpp

src/wallet/crypter.h

src/wallet/db.cpp

src/wallet/export.cpp

src/wallet/external_signer_scriptpubkeyman.cpp

src/wallet/rpc/spend.cpp

src/wallet/rpc/transactions.cpp

src/wallet/rpc/wallet.cpp

src/wallet/feebumper.cpp

src/wallet/feebumper.h

src/index/base.h

src/index/base.cpp

src/index/txindex.h

src/index/txindex.cpp

src/index/txindex_key.h

src/index/txospenderindex.h

src/index/txospenderindex.cpp

src/index/blockfilterindex.h

src/index/blockfilterindex.cpp

src/index/coinstatsindex.h

src/index/coinstatsindex.cpp

src/index/db_key.h

src/index/disktxpos.h

src/kernel/chain.cpp

src/kernel/chain.h

src/kernel/checks.cpp

src/kernel/checks.h

src/kernel/context.cpp

src/kernel/context.h

src/kernel/cs_main.cpp

src/kernel/cs_main.h

src/kernel/disconnected_transactions.cpp

src/kernel/disconnected_transactions.h

src/kernel/mempool_removal_reason.cpp

src/kernel/mempool_removal_reason.h

src/kernel/coinstats.cpp

src/kernel/coinstats.h

src/kernel/chainparams.cpp

src/kernel/chainparams.h

src/wallet/sqlite.cpp

src/wallet/sqlite.h

src/wallet/transaction.cpp

src/wallet/transaction.h

src/wallet/dump.cpp

src/wallet/dump.h

src/wallet/init.cpp

src/wallet/walletutil.cpp

src/wallet/walletutil.h

src/wallet/wallettool.cpp

src/wallet/wallettool.h

src/wallet/export.h

src/wallet/migrate.cpp

src/wallet/migrate.h

src/wallet/db.h

src/wallet/walletdb.cpp

src/wallet/interfaces.cpp

src/wallet/scriptpubkeyman.cpp

src/wallet/scriptpubkeyman.h

src/kernel/bitcoinkernel.cpp

src/kernel/bitcoinkernel.h

src/kernel/bitcoinkernel_wrapper.h

src/node/chainstate.cpp

src/node/chainstate.h

src/node/blockstorage.cpp

src/node/blockstorage.h

src/node/mempool_persist.cpp

src/node/mempool_persist.h

src/node/utxo_snapshot.cpp

src/node/utxo_snapshot.h

src/node/kernel_notifications.cpp

src/node/kernel_notifications.h

src/node/blockmanager_args.cpp

src/kernel/blockmanager_opts.h

src/util/expected.cpp

src/policy/settings.h

src/util/types.h

src/kernel/messagestartchars.h

src/kernel/warning.h

src/util/exception.h

src/common/license_info.h

src/node/coins_view_args.h

src/node/database_args.h

src/util/batchpriority.h

src/util/ui_change_type.h

src/node/coins_view_args.cpp

src/node/peerman_args.h

src/util/serfloat.h

src/node/blockmanager_args.h

src/node/database_args.cpp

src/util/overloaded.h

src/interfaces/types.h

src/node/chainstatemanager_args.h

src/node/minisketchwrapper.h

src/util/macros.h

src/util/syserror.h

src/common/run_command.h

src/util/bytevectorhash.cpp

src/node/mempool_persist_args.cpp

src/util/exec.h

src/util/rbf.h

src/crypto/hex_base.h

src/node/mempool_persist_args.h

src/interfaces/echo.h

src/util/any.h

src/util/batchpriority.cpp

src/util/threadnames.h

src/node/coin.h

src/node/mempool_args.h

src/util/asmap.h

src/util/bytevectorhash.h

src/node/context.cpp

src/util/insert.h

src/util/readwritefile.h

src/node/peerman_args.cpp

src/node/interface_ui.cpp

src/interfaces/handler.h

src/node/mining_args.h

src/util/hasher.cpp

src/common/init.h

src/kernel/mempool_limits.h

src/common/system.h

src/crypto/sha3.h

src/util/threadinterrupt.cpp

src/node/protocol_version.h

src/util/exception.cpp

src/common/messages.h

src/node/connection_types.cpp

src/util/bip32.h

src/common/license_info.cpp

src/util/stdmutex.h

src/common/run_command.cpp

src/util/check.cpp

src/util/golombrice.h

src/node/types.h

src/node/timeoffsets.h

src/util/readwritefile.cpp

src/util/fastrange.h

src/util/signalinterrupt.h

src/util/task_runner.h

src/util/syserror.cpp

src/common/interfaces.cpp

src/common/types.h

src/util/threadinterrupt.h

src/kernel/chainstatemanager_opts.h

src/node/psbt.h

src/policy/ephemeral_policy.h

src/util/trace.h

src/common/url.cpp

src/kernel/mempool_options.h

src/util/serfloat.cpp

src/kernel/notifications_interface.h

src/node/timeoffsets.cpp

src/node/warnings.cpp

src/util/hash_type.h

src/crypto/hex_base.cpp

src/node/eviction.h

src/util/tokenbucket.h

src/crypto/aes.h

src/common/pcp.h

src/util/feefrac.cpp

src/node/transaction.h

src/util/threadnames.cpp

src/common/signmessage.h

src/util/exec.cpp

src/util/signalinterrupt.cpp

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