OfferExchange::CrossOfferResult
OfferExchange::crossOffer(OfferFrame& sellingWheatOffer,
int64_t maxWheatReceived, int64_t& numWheatReceived,
int64_t maxSheepSend, int64_t& numSheepSend)
{
Asset& sheep = sellingWheatOffer.getOffer().buying;
Asset& wheat = sellingWheatOffer.getOffer().selling;
AccountID& accountBID = sellingWheatOffer.getOffer().sellerID;
Database& db = mLedgerManager.getDatabase();
AccountFrame::pointer accountB;
accountB = AccountFrame::loadAccount(accountBID, db);
if (!accountB)
{
throw std::runtime_error(
"invalid database state: offer must have matching account");
}
TrustFrame::pointer wheatLineAccountB;
if (wheat.type() != ASSET_TYPE_NATIVE)
{
wheatLineAccountB = TrustFrame::loadTrustLine(accountBID, wheat, db);
if (!wheatLineAccountB)
{
throw std::runtime_error(
"invalid database state: offer must have matching trust line");
}
}
TrustFrame::pointer sheepLineAccountB;
if (sheep.type() == ASSET_TYPE_NATIVE)
{
numWheatReceived = INT64_MAX;
}
else
{
sheepLineAccountB = TrustFrame::loadTrustLine(accountBID, sheep, db);
if (!sheepLineAccountB)
{
throw std::runtime_error(
"invalid database state: offer must have matching trust line");
}
// compute numWheatReceived based on what the account can receive
int64_t sellerMaxSheep = sheepLineAccountB->getMaxAmountReceive();
if (!bigDivide(numWheatReceived, sellerMaxSheep,
sellingWheatOffer.getOffer().price.d,
sellingWheatOffer.getOffer().price.n))
{
numWheatReceived = INT64_MAX;
}
}
// adjust numWheatReceived with what the seller has
{
int64_t wheatCanSell;
if (wheat.type() == ASSET_TYPE_NATIVE)
{
// can only send above the minimum balance
wheatCanSell = accountB->getBalanceAboveReserve(mLedgerManager);
}
else
{
if (wheatLineAccountB->isAuthorized())
{
wheatCanSell = wheatLineAccountB->getBalance();
}
else
{
wheatCanSell = 0;
}
}
if (numWheatReceived > wheatCanSell)
{
numWheatReceived = wheatCanSell;
}
}
// you can receive the lesser of the amount of wheat offered or
// the amount the guy has
if (numWheatReceived >= sellingWheatOffer.getOffer().amount)
{
numWheatReceived = sellingWheatOffer.getOffer().amount;
}
else
{
// update the offer based on the balance (to determine if it should be
// deleted or not)
// note that we don't need to write into the db at this point as the
// actual update
// is done further down
sellingWheatOffer.getOffer().amount = numWheatReceived;
}
bool reducedOffer = false;
if (numWheatReceived > maxWheatReceived)
{
numWheatReceived = maxWheatReceived;
reducedOffer = true;
}
// this guy can get X wheat to you. How many sheep does that get him?
if (!bigDivide(numSheepSend, numWheatReceived,
sellingWheatOffer.getOffer().price.n,
sellingWheatOffer.getOffer().price.d))
{
numSheepSend = INT64_MAX;
}
if (numSheepSend > maxSheepSend)
{
// reduce the number even more if there is a limit on Sheep
numSheepSend = maxSheepSend;
reducedOffer = true;
}
// bias towards seller (this cannot overflow at this point)
numWheatReceived =
bigDivide(numSheepSend, sellingWheatOffer.getOffer().price.d,
sellingWheatOffer.getOffer().price.n);
bool offerTaken = false;
if (numWheatReceived == 0 || numSheepSend == 0)
{
if (reducedOffer)
{
return eOfferCantConvert;
}
else
{
// force delete the offer as it represents a bogus offer
numWheatReceived = 0;
numSheepSend = 0;
offerTaken = true;
}
}
offerTaken =
offerTaken || sellingWheatOffer.getOffer().amount <= numWheatReceived;
if (offerTaken)
{ // entire offer is taken
sellingWheatOffer.storeDelete(mDelta, db);
accountB->addNumEntries(-1, mLedgerManager);
accountB->storeChange(mDelta, db);
}
else
{
sellingWheatOffer.getOffer().amount -= numWheatReceived;
sellingWheatOffer.storeChange(mDelta, db);
}
// Adjust balances
if (sheep.type() == ASSET_TYPE_NATIVE)
{
accountB->getAccount().balance += numSheepSend;
accountB->storeChange(mDelta, db);
}
else
{
if (!sheepLineAccountB->addBalance(numSheepSend))
{
return eOfferCantConvert;
}
sheepLineAccountB->storeChange(mDelta, db);
}
if (wheat.type() == ASSET_TYPE_NATIVE)
{
accountB->getAccount().balance -= numWheatReceived;
accountB->storeChange(mDelta, db);
}
else
{
if (!wheatLineAccountB->addBalance(-numWheatReceived))
{
return eOfferCantConvert;
}
wheatLineAccountB->storeChange(mDelta, db);
}
mOfferTrail.push_back(
ClaimOfferAtom(accountB->getID(), sellingWheatOffer.getOfferID(), wheat,
numWheatReceived, sheep, numSheepSend));
return offerTaken ? eOfferTaken : eOfferPartial;
}
bool
PathPaymentOpFrame::doApply(medida::MetricsRegistry& metrics,
LedgerDelta& delta, LedgerManager& ledgerManager)
{
Database& db = ledgerManager.getDatabase();
innerResult().code(PATH_PAYMENT_SUCCESS);
// tracks the last amount that was traded
int64_t curBReceived = mPathPayment.destAmount;
Asset curB = mPathPayment.destAsset;
// update balances, walks backwards
// build the full path to the destination, starting with sendAsset
std::vector<Asset> fullPath;
fullPath.emplace_back(mPathPayment.sendAsset);
fullPath.insert(fullPath.end(), mPathPayment.path.begin(),
mPathPayment.path.end());
bool bypassIssuerCheck = false;
// if the payment doesn't involve intermediate accounts
// and the destination is the issuer we don't bother
// checking if the destination account even exist
// so that it's always possible to send credits back to its issuer
bypassIssuerCheck = (curB.type() != ASSET_TYPE_NATIVE) &&
(fullPath.size() == 1) &&
(mPathPayment.sendAsset == mPathPayment.destAsset) &&
(getIssuer(curB) == mPathPayment.destination);
AccountFrame::pointer destination;
if (!bypassIssuerCheck)
{
destination = AccountFrame::loadAccount(mPathPayment.destination, db);
if (!destination)
{
metrics.NewMeter({"op-path-payment", "failure", "no-destination"},
"operation").Mark();
innerResult().code(PATH_PAYMENT_NO_DESTINATION);
return false;
}
}
// update last balance in the chain
if (curB.type() == ASSET_TYPE_NATIVE)
{
destination->getAccount().balance += curBReceived;
destination->storeChange(delta, db);
}
else
{
TrustFrame::pointer destLine;
if (bypassIssuerCheck)
{
destLine =
TrustFrame::loadTrustLine(mPathPayment.destination, curB, db);
}
else
{
auto tlI = TrustFrame::loadTrustLineIssuer(mPathPayment.destination,
curB, db);
if (!tlI.second)
{
metrics.NewMeter({"op-path-payment", "failure", "no-issuer"},
"operation").Mark();
innerResult().code(PATH_PAYMENT_NO_ISSUER);
innerResult().noIssuer() = curB;
return false;
}
destLine = tlI.first;
}
if (!destLine)
{
metrics.NewMeter({"op-path-payment", "failure", "no-trust"},
"operation").Mark();
innerResult().code(PATH_PAYMENT_NO_TRUST);
return false;
}
if (!destLine->isAuthorized())
{
metrics.NewMeter({"op-path-payment", "failure", "not-authorized"},
"operation").Mark();
innerResult().code(PATH_PAYMENT_NOT_AUTHORIZED);
return false;
}
if (!destLine->addBalance(curBReceived))
{
metrics.NewMeter({"op-path-payment", "failure", "line-full"},
"operation").Mark();
innerResult().code(PATH_PAYMENT_LINE_FULL);
return false;
}
destLine->storeChange(delta, db);
}
innerResult().success().last =
SimplePaymentResult(mPathPayment.destination, curB, curBReceived);
// now, walk the path backwards
for (int i = (int)fullPath.size() - 1; i >= 0; i--)
{
int64_t curASent, actualCurBReceived;
Asset const& curA = fullPath[i];
if (curA == curB)
{
continue;
}
if (curA.type() != ASSET_TYPE_NATIVE)
{
if (!AccountFrame::loadAccount(getIssuer(curA), db))
{
metrics.NewMeter({"op-path-payment", "failure", "no-issuer"},
"operation").Mark();
innerResult().code(PATH_PAYMENT_NO_ISSUER);
innerResult().noIssuer() = curA;
return false;
}
}
OfferExchange oe(delta, ledgerManager);
// curA -> curB
OfferExchange::ConvertResult r = oe.convertWithOffers(
curA, INT64_MAX, curASent, curB, curBReceived, actualCurBReceived,
[this, &metrics](OfferFrame const& o)
{
if (o.getSellerID() == getSourceID())
{
// we are crossing our own offer, potentially invalidating
// mSourceAccount (balance or numSubEntries)
metrics.NewMeter({"op-path-payment", "failure",
"offer-cross-self"},
"operation").Mark();
innerResult().code(PATH_PAYMENT_OFFER_CROSS_SELF);
return OfferExchange::eStop;
}
return OfferExchange::eKeep;
});
switch (r)
{
case OfferExchange::eFilterStop:
return false;
case OfferExchange::eOK:
if (curBReceived == actualCurBReceived)
{
break;
}
// fall through
case OfferExchange::ePartial:
metrics.NewMeter({"op-path-payment", "failure", "too-few-offers"},
"operation").Mark();
innerResult().code(PATH_PAYMENT_TOO_FEW_OFFERS);
return false;
}
assert(curBReceived == actualCurBReceived);
curBReceived = curASent; // next round, we need to send enough
curB = curA;
// add offers that got taken on the way
// insert in front to match the path's order
auto& offers = innerResult().success().offers;
offers.insert(offers.begin(), oe.getOfferTrail().begin(),
oe.getOfferTrail().end());
}
// last step: we've reached the first account in the chain, update its
// balance
int64_t curBSent;
curBSent = curBReceived;
if (curBSent > mPathPayment.sendMax)
{ // make sure not over the max
metrics.NewMeter({"op-path-payment", "failure", "over-send-max"},
"operation").Mark();
innerResult().code(PATH_PAYMENT_OVER_SENDMAX);
return false;
}
if (curB.type() == ASSET_TYPE_NATIVE)
{
int64_t minBalance = mSourceAccount->getMinimumBalance(ledgerManager);
if ((mSourceAccount->getAccount().balance - curBSent) < minBalance)
{ // they don't have enough to send
metrics.NewMeter({"op-path-payment", "failure", "underfunded"},
"operation").Mark();
innerResult().code(PATH_PAYMENT_UNDERFUNDED);
return false;
}
mSourceAccount->getAccount().balance -= curBSent;
mSourceAccount->storeChange(delta, db);
}
else
{
TrustFrame::pointer sourceLineFrame;
if (bypassIssuerCheck)
{
sourceLineFrame =
TrustFrame::loadTrustLine(getSourceID(), curB, db);
}
else
{
auto tlI = TrustFrame::loadTrustLineIssuer(getSourceID(), curB, db);
if (!tlI.second)
{
metrics.NewMeter({"op-path-payment", "failure", "no-issuer"},
"operation").Mark();
innerResult().code(PATH_PAYMENT_NO_ISSUER);
innerResult().noIssuer() = curB;
return false;
}
sourceLineFrame = tlI.first;
}
if (!sourceLineFrame)
{
metrics.NewMeter({"op-path-payment", "failure", "src-no-trust"},
"operation").Mark();
innerResult().code(PATH_PAYMENT_SRC_NO_TRUST);
return false;
}
if (!sourceLineFrame->isAuthorized())
{
metrics.NewMeter(
{"op-path-payment", "failure", "src-not-authorized"},
"operation").Mark();
innerResult().code(PATH_PAYMENT_SRC_NOT_AUTHORIZED);
return false;
}
if (!sourceLineFrame->addBalance(-curBSent))
{
metrics.NewMeter({"op-path-payment", "failure", "underfunded"},
"operation").Mark();
innerResult().code(PATH_PAYMENT_UNDERFUNDED);
return false;
}
sourceLineFrame->storeChange(delta, db);
}
metrics.NewMeter({"op-path-payment", "success", "apply"}, "operation")
.Mark();
return true;
}
bool
PathPaymentOpFrame::doApply(medida::MetricsRegistry& metrics,
LedgerDelta& delta, LedgerManager& ledgerManager)
{
AccountFrame::pointer destination;
Database& db = ledgerManager.getDatabase();
destination = AccountFrame::loadAccount(mPathPayment.destination, db);
if (!destination)
{
metrics.NewMeter({"op-path-payment", "failure", "no-destination"},
"operation").Mark();
innerResult().code(PATH_PAYMENT_NO_DESTINATION);
return false;
}
innerResult().code(PATH_PAYMENT_SUCCESS);
// tracks the last amount that was traded
int64_t curBReceived = mPathPayment.destAmount;
Asset curB = mPathPayment.destAsset;
// update balances, walks backwards
// build the full path to the destination, starting with sendAsset
std::vector<Asset> fullPath;
fullPath.emplace_back(mPathPayment.sendAsset);
fullPath.insert(fullPath.end(), mPathPayment.path.begin(),
mPathPayment.path.end());
// update last balance in the chain
{
if (curB.type() == ASSET_TYPE_NATIVE)
{
destination->getAccount().balance += curBReceived;
destination->storeChange(delta, db);
}
else
{
TrustFrame::pointer destLine;
destLine =
TrustFrame::loadTrustLine(destination->getID(), curB, db);
if (!destLine)
{
metrics.NewMeter({"op-path-payment", "failure", "no-trust"},
"operation").Mark();
innerResult().code(PATH_PAYMENT_NO_TRUST);
return false;
}
if (!destLine->isAuthorized())
{
metrics.NewMeter(
{"op-path-payment", "failure", "not-authorized"},
"operation").Mark();
innerResult().code(PATH_PAYMENT_NOT_AUTHORIZED);
return false;
}
if (!destLine->addBalance(curBReceived))
{
metrics.NewMeter({"op-path-payment", "failure", "line-full"},
"operation").Mark();
innerResult().code(PATH_PAYMENT_LINE_FULL);
return false;
}
destLine->storeChange(delta, db);
}
innerResult().success().last =
SimplePaymentResult(destination->getID(), curB, curBReceived);
}
// now, walk the path backwards
for (int i = (int)fullPath.size() - 1; i >= 0; i--)
{
int64_t curASent, actualCurBReceived;
Asset const& curA = fullPath[i];
if (curA == curB)
{
continue;
}
OfferExchange oe(delta, ledgerManager);
// curA -> curB
OfferExchange::ConvertResult r =
oe.convertWithOffers(curA, INT64_MAX, curASent, curB, curBReceived,
actualCurBReceived, nullptr);
switch (r)
{
case OfferExchange::eFilterStop:
assert(false); // no filter -> should not happen
break;
case OfferExchange::eOK:
if (curBReceived == actualCurBReceived)
{
break;
}
// fall through
case OfferExchange::ePartial:
metrics.NewMeter({"op-path-payment", "failure", "too-few-offers"},
"operation").Mark();
innerResult().code(PATH_PAYMENT_TOO_FEW_OFFERS);
return false;
}
assert(curBReceived == actualCurBReceived);
curBReceived = curASent; // next round, we need to send enough
curB = curA;
// add offers that got taken on the way
// insert in front to match the path's order
auto& offers = innerResult().success().offers;
offers.insert(offers.begin(), oe.getOfferTrail().begin(),
oe.getOfferTrail().end());
}
// last step: we've reached the first account in the chain, update its
// balance
int64_t curBSent;
curBSent = curBReceived;
if (curBSent > mPathPayment.sendMax)
{ // make sure not over the max
metrics.NewMeter({"op-path-payment", "failure", "over-send-max"},
"operation").Mark();
innerResult().code(PATH_PAYMENT_OVER_SENDMAX);
return false;
}
if (curB.type() == ASSET_TYPE_NATIVE)
{
int64_t minBalance = mSourceAccount->getMinimumBalance(ledgerManager);
if ((mSourceAccount->getAccount().balance - curBSent) < minBalance)
{ // they don't have enough to send
metrics.NewMeter({"op-path-payment", "failure", "underfunded"},
"operation").Mark();
innerResult().code(PATH_PAYMENT_UNDERFUNDED);
return false;
}
mSourceAccount->getAccount().balance -= curBSent;
mSourceAccount->storeChange(delta, db);
}
else
{
AccountFrame::pointer issuer;
if(curB.type()==ASSET_TYPE_CREDIT_ALPHANUM4)
issuer = AccountFrame::loadAccount(curB.alphaNum4().issuer, db);
else if(curB.type()==ASSET_TYPE_CREDIT_ALPHANUM12)
issuer = AccountFrame::loadAccount(curB.alphaNum12().issuer, db);
if (!issuer)
{
metrics.NewMeter({"op-path-payment", "failure", "no-issuer"},
"operation").Mark();
throw std::runtime_error("sendCredit Issuer not found");
}
TrustFrame::pointer sourceLineFrame;
sourceLineFrame = TrustFrame::loadTrustLine(getSourceID(), curB, db);
if (!sourceLineFrame)
{
metrics.NewMeter({"op-path-payment", "failure", "src-no-trust"},
"operation").Mark();
innerResult().code(PATH_PAYMENT_SRC_NO_TRUST);
return false;
}
if (!sourceLineFrame->isAuthorized())
{
metrics.NewMeter(
{"op-path-payment", "failure", "src-not-authorized"},
"operation").Mark();
innerResult().code(PATH_PAYMENT_SRC_NOT_AUTHORIZED);
return false;
}
if (!sourceLineFrame->addBalance(-curBSent))
{
metrics.NewMeter({"op-path-payment", "failure", "underfunded"},
"operation").Mark();
innerResult().code(PATH_PAYMENT_UNDERFUNDED);
return false;
}
sourceLineFrame->storeChange(delta, db);
}
metrics.NewMeter({"op-path-payment", "success", "apply"}, "operation")
.Mark();
return true;
}