src/policy/rbf.cpp

   1 // Copyright (c) 2016-2017 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 #include <policy/rbf.h>
   6
   7 bool SignalsOptInRBF(const CTransaction &tx)
   8 {
   9     for (const CTxIn &txin : tx.vin) {
  10         if (txin.nSequence < std::numeric_limits<unsigned int>::max()-1) {
  11             return true;
  12         }
  13     }
  14     return false;
  15 }
  16
  17 RBFTransactionState IsRBFOptIn(const CTransaction &tx, CTxMemPool &pool)
  18 {
  19     AssertLockHeld(pool.cs);
  20
  21     CTxMemPool::setEntries setAncestors;
  22
  23     // First check the transaction itself.
  24     if (SignalsOptInRBF(tx)) {
  25         return RBF_TRANSACTIONSTATE_REPLACEABLE_BIP125;
  26     }
  27
  28     // If this transaction is not in our mempool, then we can't be sure
  29     // we will know about all its inputs.
  30     if (!pool.exists(tx.GetHash())) {
  31         return RBF_TRANSACTIONSTATE_UNKNOWN;
  32     }
  33
  34     // If all the inputs have nSequence >= maxint-1, it still might be
  35     // signaled for RBF if any unconfirmed parents have signaled.
  36     uint64_t noLimit = std::numeric_limits<uint64_t>::max();
  37     std::string dummy;
  38     CTxMemPoolEntry entry = *pool.mapTx.find(tx.GetHash());
  39     pool.CalculateMemPoolAncestors(entry, setAncestors, noLimit, noLimit, noLimit, noLimit, dummy, false);
  40
  41     for (CTxMemPool::txiter it : setAncestors) {
  42         if (SignalsOptInRBF(it->GetTx())) {
  43             return RBF_TRANSACTIONSTATE_REPLACEABLE_BIP125;
  44         }
  45     }
  46     return RBF_TRANSACTIONSTATE_FINAL;
  47 }