foster/bitcoin-bitcoin-core
0
0
Fork 0
mirror of https://github.com/bitcoin/bitcoin.git synced 2025-02-02 09:46:52 -05:00
Code Issues Activity

refactor + document coin selection strategy

Browse source 
Co-authored-by: Xekyo <murch@murch.one>
This commit is contained in:
glozow 2021-04-22 06:17:21 -07:00
parent 58ea324fdd
commit 6ba892126d
1 changed files with 50 additions and 13 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

63
src/wallet/wallet.cpp
View file

@ -2478,7 +2478,7 @@ bool CWallet::SelectCoins(const std::vector<COutput>& vAvailableCoins, const CAm
}
}
// remove preset inputs from vCoins
// remove preset inputs from vCoins so that Coin Selection doesn't pick them.
for (std::vector<COutput>::iterator it = vCoins.begin(); it != vCoins.end() && coin_control.HasSelected();)
{
if (setPresetCoins.count(it->GetInputCoin()))
@ -2490,9 +2490,9 @@ bool CWallet::SelectCoins(const std::vector<COutput>& vAvailableCoins, const CAm
unsigned int limit_ancestor_count = 0;
unsigned int limit_descendant_count = 0;
chain().getPackageLimits(limit_ancestor_count, limit_descendant_count);
size_t max_ancestors = (size_t)std::max<int64_t>(1, limit_ancestor_count);
size_t max_descendants = (size_t)std::max<int64_t>(1, limit_descendant_count);
bool fRejectLongChains = gArgs.GetBoolArg("-walletrejectlongchains", DEFAULT_WALLET_REJECT_LONG_CHAINS);
const size_t max_ancestors = (size_t)std::max<int64_t>(1, limit_ancestor_count);
const size_t max_descendants = (size_t)std::max<int64_t>(1, limit_descendant_count);
const bool fRejectLongChains = gArgs.GetBoolArg("-walletrejectlongchains", DEFAULT_WALLET_REJECT_LONG_CHAINS);
// form groups from remaining coins; note that preset coins will not
// automatically have their associated (same address) coins included
@ -2502,16 +2502,53 @@ bool CWallet::SelectCoins(const std::vector<COutput>& vAvailableCoins, const CAm
// explicitly shuffling the outputs before processing
Shuffle(vCoins.begin(), vCoins.end(), FastRandomContext());
}
bool res = value_to_select <= 0 ||
SelectCoinsMinConf(value_to_select, CoinEligibilityFilter(1, 6, 0), vCoins, setCoinsRet, nValueRet, coin_selection_params, bnb_used) ||
SelectCoinsMinConf(value_to_select, CoinEligibilityFilter(1, 1, 0), vCoins, setCoinsRet, nValueRet, coin_selection_params, bnb_used) ||
(m_spend_zero_conf_change && SelectCoinsMinConf(value_to_select, CoinEligibilityFilter(0, 1, 2), vCoins, setCoinsRet, nValueRet, coin_selection_params, bnb_used)) ||
(m_spend_zero_conf_change && SelectCoinsMinConf(value_to_select, CoinEligibilityFilter(0, 1, std::min((size_t)4, max_ancestors/3), std::min((size_t)4, max_descendants/3)), vCoins, setCoinsRet, nValueRet, coin_selection_params, bnb_used)) ||
(m_spend_zero_conf_change && SelectCoinsMinConf(value_to_select, CoinEligibilityFilter(0, 1, max_ancestors/2, max_descendants/2), vCoins, setCoinsRet, nValueRet, coin_selection_params, bnb_used)) ||
(m_spend_zero_conf_change && SelectCoinsMinConf(value_to_select, CoinEligibilityFilter(0, 1, max_ancestors-1, max_descendants-1, true /* include_partial_groups */), vCoins, setCoinsRet, nValueRet, coin_selection_params, bnb_used)) ||
(m_spend_zero_conf_change && !fRejectLongChains && SelectCoinsMinConf(value_to_select, CoinEligibilityFilter(0, 1, std::numeric_limits<uint64_t>::max(), std::numeric_limits<uint64_t>::max(), true /* include_partial_groups */), vCoins, setCoinsRet, nValueRet, coin_selection_params, bnb_used));
// because SelectCoinsMinConf clears the setCoinsRet, we now add the possible inputs to the coinset
// Coin Selection attempts to select inputs from a pool of eligible UTXOs to fund the
// transaction at a target feerate. If an attempt fails, more attempts may be made using a more
// permissive CoinEligibilityFilter.
const bool res = [&] {
// Pre-selected inputs already cover the target amount.
if (value_to_select <= 0) return true;
// If possible, fund the transaction with confirmed UTXOs only. Prefer at least six
// confirmations on outputs received from other wallets and only spend confirmed change.
if (SelectCoinsMinConf(value_to_select, CoinEligibilityFilter(1, 6, 0), vCoins, setCoinsRet, nValueRet, coin_selection_params, bnb_used)) return true;
if (SelectCoinsMinConf(value_to_select, CoinEligibilityFilter(1, 1, 0), vCoins, setCoinsRet, nValueRet, coin_selection_params, bnb_used)) return true;
// Fall back to using zero confirmation change (but with as few ancestors in the mempool as
// possible) if we cannot fund the transaction otherwise. We never spend unconfirmed
// outputs received from other wallets.
if (m_spend_zero_conf_change) {
if (SelectCoinsMinConf(value_to_select, CoinEligibilityFilter(0, 1, 2), vCoins, setCoinsRet, nValueRet, coin_selection_params, bnb_used)) return true;
if (SelectCoinsMinConf(value_to_select, CoinEligibilityFilter(0, 1, std::min((size_t)4, max_ancestors/3), std::min((size_t)4, max_descendants/3)),
vCoins, setCoinsRet, nValueRet, coin_selection_params, bnb_used)) {
return true;
}
if (SelectCoinsMinConf(value_to_select, CoinEligibilityFilter(0, 1, max_ancestors/2, max_descendants/2),
vCoins, setCoinsRet, nValueRet, coin_selection_params, bnb_used)) {
return true;
}
// If partial groups are allowed, relax the requirement of spending OutputGroups (groups
// of UTXOs sent to the same address, which are obviously controlled by a single wallet)
// in their entirety.
if (SelectCoinsMinConf(value_to_select, CoinEligibilityFilter(0, 1, max_ancestors-1, max_descendants-1, true /* include_partial_groups */),
vCoins, setCoinsRet, nValueRet, coin_selection_params, bnb_used)) {
return true;
}
// Try with unlimited ancestors/descendants. The transaction will still need to meet
// mempool ancestor/descendant policy to be accepted to mempool and broadcasted, but
// OutputGroups use heuristics that may overestimate ancestor/descendant counts.
if (!fRejectLongChains && SelectCoinsMinConf(value_to_select,
CoinEligibilityFilter(0, 1, std::numeric_limits<uint64_t>::max(), std::numeric_limits<uint64_t>::max(), true /* include_partial_groups */),
vCoins, setCoinsRet, nValueRet, coin_selection_params, bnb_used)) {
return true;
}
}
// Coin Selection failed.
return false;
}();
// SelectCoinsMinConf clears setCoinsRet, so add the preset inputs from coin_control to the coinset
util::insert(setCoinsRet, setPresetCoins);
// add preset inputs to the total value selected