lbrycrd/src/wallet/coinselection.h
2018-07-27 07:15:02 -04:00

101 lines
3.6 KiB
C++

// 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_WALLET_COINSELECTION_H
#define BITCOIN_WALLET_COINSELECTION_H
#include <amount.h>
#include <primitives/transaction.h>
#include <random.h>
//! target minimum change amount
static const CAmount MIN_CHANGE = CENT;
//! final minimum change amount after paying for fees
static const CAmount MIN_FINAL_CHANGE = MIN_CHANGE/2;
class CInputCoin {
public:
CInputCoin(const CTransactionRef& tx, unsigned int i)
{
if (!tx)
throw std::invalid_argument("tx should not be null");
if (i >= tx->vout.size())
throw std::out_of_range("The output index is out of range");
outpoint = COutPoint(tx->GetHash(), i);
txout = tx->vout[i];
effective_value = txout.nValue;
}
CInputCoin(const CTransactionRef& tx, unsigned int i, int input_bytes) : CInputCoin(tx, i)
{
m_input_bytes = input_bytes;
}
COutPoint outpoint;
CTxOut txout;
CAmount effective_value;
/** Pre-computed estimated size of this output as a fully-signed input in a transaction. Can be -1 if it could not be calculated */
int m_input_bytes{-1};
bool operator<(const CInputCoin& rhs) const {
return outpoint < rhs.outpoint;
}
bool operator!=(const CInputCoin& rhs) const {
return outpoint != rhs.outpoint;
}
bool operator==(const CInputCoin& rhs) const {
return outpoint == rhs.outpoint;
}
};
struct CoinEligibilityFilter
{
const int conf_mine;
const int conf_theirs;
const uint64_t max_ancestors;
const uint64_t max_descendants;
CoinEligibilityFilter(int conf_mine, int conf_theirs, uint64_t max_ancestors) : conf_mine(conf_mine), conf_theirs(conf_theirs), max_ancestors(max_ancestors), max_descendants(max_ancestors) {}
CoinEligibilityFilter(int conf_mine, int conf_theirs, uint64_t max_ancestors, uint64_t max_descendants) : conf_mine(conf_mine), conf_theirs(conf_theirs), max_ancestors(max_ancestors), max_descendants(max_descendants) {}
};
struct OutputGroup
{
std::vector<CInputCoin> m_outputs;
bool m_from_me{true};
CAmount m_value{0};
int m_depth{999};
size_t m_ancestors{0};
size_t m_descendants{0};
CAmount effective_value{0};
CAmount fee{0};
CAmount long_term_fee{0};
OutputGroup() {}
OutputGroup(std::vector<CInputCoin>&& outputs, bool from_me, CAmount value, int depth, size_t ancestors, size_t descendants)
: m_outputs(std::move(outputs))
, m_from_me(from_me)
, m_value(value)
, m_depth(depth)
, m_ancestors(ancestors)
, m_descendants(descendants)
{}
OutputGroup(const CInputCoin& output, int depth, bool from_me, size_t ancestors, size_t descendants) : OutputGroup() {
Insert(output, depth, from_me, ancestors, descendants);
}
void Insert(const CInputCoin& output, int depth, bool from_me, size_t ancestors, size_t descendants);
std::vector<CInputCoin>::iterator Discard(const CInputCoin& output);
bool EligibleForSpending(const CoinEligibilityFilter& eligibility_filter) const;
};
bool SelectCoinsBnB(std::vector<OutputGroup>& utxo_pool, const CAmount& target_value, const CAmount& cost_of_change, std::set<CInputCoin>& out_set, CAmount& value_ret, CAmount not_input_fees);
// Original coin selection algorithm as a fallback
bool KnapsackSolver(const CAmount& nTargetValue, std::vector<OutputGroup>& groups, std::set<CInputCoin>& setCoinsRet, CAmount& nValueRet);
#endif // BITCOIN_WALLET_COINSELECTION_H