Files
rippled/src/xrpld/app/misc/FeeVoteImpl.cpp
2026-04-23 15:01:01 -07:00

326 lines
10 KiB
C++

#include <xrpld/app/misc/FeeVote.h>
#include <xrpld/core/Config.h>
#include <xrpl/basics/Log.h>
#include <xrpl/basics/base_uint.h>
#include <xrpl/beast/utility/Journal.h>
#include <xrpl/beast/utility/instrumentation.h>
#include <xrpl/ledger/ReadView.h>
#include <xrpl/protocol/Feature.h>
#include <xrpl/protocol/Fees.h>
#include <xrpl/protocol/Protocol.h>
#include <xrpl/protocol/SField.h>
#include <xrpl/protocol/STTx.h>
#include <xrpl/protocol/STValidation.h>
#include <xrpl/protocol/Serializer.h>
#include <xrpl/protocol/SystemParameters.h>
#include <xrpl/protocol/TxFormats.h>
#include <xrpl/protocol/XRPAmount.h>
#include <xrpl/shamap/SHAMap.h>
#include <xrpl/shamap/SHAMapItem.h>
#include <xrpl/shamap/SHAMapTreeNode.h>
#include <algorithm>
#include <cstdint>
#include <limits>
#include <map>
#include <memory>
#include <utility>
#include <vector>
namespace xrpl {
namespace detail {
class VotableValue
{
private:
using value_type = XRPAmount;
value_type const current_; // The current setting
value_type const target_; // The setting we want
std::map<value_type, int> voteMap_;
public:
VotableValue(value_type current, value_type target) : current_(current), target_(target)
{
// Add our vote
++voteMap_[target_];
}
void
addVote(value_type vote)
{
++voteMap_[vote];
}
void
noVote()
{
addVote(current_);
}
value_type
current() const
{
return current_;
}
std::pair<value_type, bool>
getVotes() const;
};
auto
VotableValue::getVotes() const -> std::pair<value_type, bool>
{
value_type ourVote = current_;
int weight = 0;
for (auto const& [key, val] : voteMap_)
{
// Take most voted value between current and target, inclusive
if ((key <= std::max(target_, current_)) && (key >= std::min(target_, current_)) &&
(val > weight))
{
ourVote = key;
weight = val;
}
}
return {ourVote, ourVote != current_};
}
} // namespace detail
//------------------------------------------------------------------------------
class FeeVoteImpl : public FeeVote
{
private:
FeeSetup target_;
beast::Journal const journal_;
public:
FeeVoteImpl(FeeSetup const& setup, beast::Journal journal);
void
doValidation(Fees const& lastFees, Rules const& rules, STValidation& val) override;
void
doVoting(
std::shared_ptr<ReadView const> const& lastClosedLedger,
std::vector<std::shared_ptr<STValidation>> const& parentValidations,
std::shared_ptr<SHAMap> const& initialPosition) override;
};
//--------------------------------------------------------------------------
FeeVoteImpl::FeeVoteImpl(FeeSetup const& setup, beast::Journal journal)
: target_(setup), journal_(journal)
{
}
void
FeeVoteImpl::doValidation(Fees const& lastFees, Rules const& rules, STValidation& v)
{
// Values should always be in a valid range (because the voting process
// will ignore out-of-range values) but if we detect such a case, we do
// not send a value.
if (rules.enabled(featureXRPFees))
{
auto vote =
[&v, this](auto const current, XRPAmount target, char const* name, auto const& sfield) {
if (current != target)
{
JLOG(journal_.info()) << "Voting for " << name << " of " << target;
v[sfield] = target;
}
};
vote(lastFees.base, target_.reference_fee, "base fee", sfBaseFeeDrops);
vote(lastFees.reserve, target_.account_reserve, "base reserve", sfReserveBaseDrops);
vote(
lastFees.increment,
target_.owner_reserve,
"reserve increment",
sfReserveIncrementDrops);
}
else
{
auto to32 = [](XRPAmount target) { return target.dropsAs<std::uint32_t>(); };
auto to64 = [](XRPAmount target) { return target.dropsAs<std::uint64_t>(); };
auto vote = [&v, this](
auto const current,
XRPAmount target,
auto const& convertCallback,
char const* name,
auto const& sfield) {
if (current != target)
{
JLOG(journal_.info()) << "Voting for " << name << " of " << target;
if (auto const f = convertCallback(target))
v[sfield] = *f;
}
};
vote(lastFees.base, target_.reference_fee, to64, "base fee", sfBaseFee);
vote(lastFees.reserve, target_.account_reserve, to32, "base reserve", sfReserveBase);
vote(
lastFees.increment,
target_.owner_reserve,
to32,
"reserve increment",
sfReserveIncrement);
}
}
void
FeeVoteImpl::doVoting(
std::shared_ptr<ReadView const> const& lastClosedLedger,
std::vector<std::shared_ptr<STValidation>> const& set,
std::shared_ptr<SHAMap> const& initialPosition)
{
// LCL must be flag ledger
XRPL_ASSERT(
lastClosedLedger && isFlagLedger(lastClosedLedger->seq()),
"xrpl::FeeVoteImpl::doVoting : has a flag ledger");
detail::VotableValue baseFeeVote(lastClosedLedger->fees().base, target_.reference_fee);
detail::VotableValue baseReserveVote(lastClosedLedger->fees().reserve, target_.account_reserve);
detail::VotableValue incReserveVote(lastClosedLedger->fees().increment, target_.owner_reserve);
auto const& rules = lastClosedLedger->rules();
if (rules.enabled(featureXRPFees))
{
auto doVote = [](std::shared_ptr<STValidation> const& val,
detail::VotableValue& value,
SF_AMOUNT const& xrpField) {
if (auto const field = ~val->at(~xrpField); field && field->native())
{
auto const vote = field->xrp();
if (isLegalAmountSigned(vote))
{
value.addVote(vote);
}
else
{
value.noVote();
}
}
else
{
value.noVote();
}
};
for (auto const& val : set)
{
if (!val->isTrusted())
continue;
doVote(val, baseFeeVote, sfBaseFeeDrops);
doVote(val, baseReserveVote, sfReserveBaseDrops);
doVote(val, incReserveVote, sfReserveIncrementDrops);
}
}
else
{
auto doVote = [](std::shared_ptr<STValidation> const& val,
detail::VotableValue& value,
auto const& valueField) {
if (auto const field = val->at(~valueField))
{
using XRPType = XRPAmount::value_type;
auto const vote = *field;
if (vote <= std::numeric_limits<XRPType>::max() &&
isLegalAmountSigned(XRPAmount{unsafe_cast<XRPType>(vote)}))
{
value.addVote(XRPAmount{unsafe_cast<XRPType>(vote)});
}
else
{
// Invalid amounts will be treated as if they're
// not provided. Don't throw because this value is
// provided by an external entity.
value.noVote();
}
}
else
{
value.noVote();
}
};
for (auto const& val : set)
{
if (!val->isTrusted())
continue;
doVote(val, baseFeeVote, sfBaseFee);
doVote(val, baseReserveVote, sfReserveBase);
doVote(val, incReserveVote, sfReserveIncrement);
}
}
// choose our positions
// TODO: Use structured binding once LLVM 16 is the minimum supported
// version. See also: https://github.com/llvm/llvm-project/issues/48582
// https://github.com/llvm/llvm-project/commit/127bf44385424891eb04cff8e52d3f157fc2cb7c
auto const baseFee = baseFeeVote.getVotes();
auto const baseReserve = baseReserveVote.getVotes();
auto const incReserve = incReserveVote.getVotes();
auto const seq = lastClosedLedger->header().seq + 1;
// add transactions to our position
if (baseFee.second || baseReserve.second || incReserve.second)
{
JLOG(journal_.warn()) << "We are voting for a fee change: " << baseFee.first << "/"
<< baseReserve.first << "/" << incReserve.first;
STTx const feeTx(ttFEE, [=, &rules](auto& obj) {
obj[sfAccount] = AccountID();
obj[sfLedgerSequence] = seq;
if (rules.enabled(featureXRPFees))
{
obj[sfBaseFeeDrops] = baseFee.first;
obj[sfReserveBaseDrops] = baseReserve.first;
obj[sfReserveIncrementDrops] = incReserve.first;
}
else
{
// Without the featureXRPFees amendment, these fields are
// required.
obj[sfBaseFee] = baseFee.first.dropsAs<std::uint64_t>(baseFeeVote.current());
obj[sfReserveBase] =
baseReserve.first.dropsAs<std::uint32_t>(baseReserveVote.current());
obj[sfReserveIncrement] =
incReserve.first.dropsAs<std::uint32_t>(incReserveVote.current());
obj[sfReferenceFeeUnits] = FEE_UNITS_DEPRECATED;
}
});
uint256 const txID = feeTx.getTransactionID();
JLOG(journal_.warn()) << "Vote: " << txID;
Serializer s;
feeTx.add(s);
if (!initialPosition->addGiveItem(
SHAMapNodeType::tnTRANSACTION_NM, make_shamapitem(txID, s.slice())))
{
JLOG(journal_.warn()) << "Ledger already had fee change";
}
}
}
//------------------------------------------------------------------------------
std::unique_ptr<FeeVote>
make_FeeVote(FeeSetup const& setup, beast::Journal journal)
{
return std::make_unique<FeeVoteImpl>(setup, journal);
}
} // namespace xrpl