// OPTIMIZE: When calculating path increment, note if increment consumes all
// liquidity. No need to revisit path in the future if all liquidity is used.
//
TER PathCursor::advanceNode (bool const bReverse) const
{
TER resultCode = tesSUCCESS;
// Taker is the active party against an offer in the ledger - the entity
// that is taking advantage of an offer in the order book.
WriteLog (lsTRACE, RippleCalc)
<< "advanceNode: TakerPays:"
<< node().saTakerPays << " TakerGets:" << node().saTakerGets;
int loopCount = 0;
do
{
// VFALCO NOTE Why not use a for() loop?
// VFALCO TODO The limit on loop iterations puts an
// upper limit on the number of different quality
// levels (ratio of pay:get) that will be considered for one path.
// Changing this value has repercusssions on validation and consensus.
//
if (++loopCount > NODE_ADVANCE_MAX_LOOPS)
{
WriteLog (lsWARNING, RippleCalc) << "Loop count exceeded";
return tefEXCEPTION;
}
bool bDirectDirDirty = node().directory.initialize (
{ previousNode().issue_, node().issue_},
view());
if (auto advance = node().directory.advance (view()))
{
bDirectDirDirty = true;
if (advance == NodeDirectory::NEW_QUALITY)
{
// We didn't run off the end of this order book and found
// another quality directory.
WriteLog (lsTRACE, RippleCalc)
<< "advanceNode: Quality advance: node.directory.current="
<< node().directory.current;
}
else if (bReverse)
{
WriteLog (lsTRACE, RippleCalc)
<< "advanceNode: No more offers.";
node().offerIndex_ = 0;
break;
}
else
{
// No more offers. Should be done rather than fall off end of
// book.
WriteLog (lsWARNING, RippleCalc)
<< "advanceNode: Unreachable: "
<< "Fell off end of order book.";
// FIXME: why?
return telFAILED_PROCESSING;
}
}
if (bDirectDirDirty)
{
// Our quality changed since last iteration.
// Use the rate from the directory.
node().saOfrRate = amountFromQuality (
getQuality (node().directory.current));
// For correct ratio
node().uEntry = 0;
node().bEntryAdvance = true;
WriteLog (lsTRACE, RippleCalc)
<< "advanceNode: directory dirty: node.saOfrRate="
<< node().saOfrRate;
}
if (!node().bEntryAdvance)
{
if (node().bFundsDirty)
{
// We were called again probably merely to update structure
// variables.
node().saTakerPays
= node().sleOffer->getFieldAmount (sfTakerPays);
node().saTakerGets
= node().sleOffer->getFieldAmount (sfTakerGets);
// Funds left.
node().saOfferFunds = accountFunds(view(),
node().offerOwnerAccount_,
node().saTakerGets,
fhZERO_IF_FROZEN,
getConfig());
node().bFundsDirty = false;
WriteLog (lsTRACE, RippleCalc)
<< "advanceNode: funds dirty: node().saOfrRate="
<< node().saOfrRate;
}
else
{
WriteLog (lsTRACE, RippleCalc) << "advanceNode: as is";
}
}
else if (!dirNext (view(),
node().directory.current,
node().directory.ledgerEntry,
node().uEntry,
node().offerIndex_))
// This is the only place that offerIndex_ changes.
{
// Failed to find an entry in directory.
// Do another cur directory iff multiQuality_
if (multiQuality_)
{
// We are allowed to process multiple qualities if this is the
// only path.
WriteLog (lsTRACE, RippleCalc)
<< "advanceNode: next quality";
node().directory.advanceNeeded = true; // Process next quality.
}
else if (!bReverse)
{
// We didn't run dry going backwards - why are we running dry
// going forwards - this should be impossible!
// TODO(tom): these warnings occur in production! They
// shouldn't.
WriteLog (lsWARNING, RippleCalc)
<< "advanceNode: unreachable: ran out of offers";
return telFAILED_PROCESSING;
}
else
{
// Ran off end of offers.
node().bEntryAdvance = false; // Done.
node().offerIndex_ = 0; // Report no more entries.
}
}
else
{
// Got a new offer.
node().sleOffer = view().peek (keylet::offer(node().offerIndex_));
if (!node().sleOffer)
{
// Corrupt directory that points to an entry that doesn't exist.
// This has happened in production.
WriteLog (lsWARNING, RippleCalc) <<
"Missing offer in directory";
node().bEntryAdvance = true;
}
else
{
node().offerOwnerAccount_
= node().sleOffer->getAccountID (sfAccount);
node().saTakerPays
= node().sleOffer->getFieldAmount (sfTakerPays);
node().saTakerGets
= node().sleOffer->getFieldAmount (sfTakerGets);
AccountIssue const accountIssue (
node().offerOwnerAccount_, node().issue_);
WriteLog (lsTRACE, RippleCalc)
<< "advanceNode: offerOwnerAccount_="
<< to_string (node().offerOwnerAccount_)
<< " node.saTakerPays=" << node().saTakerPays
<< " node.saTakerGets=" << node().saTakerGets
<< " node.offerIndex_=" << node().offerIndex_;
if (node().sleOffer->isFieldPresent (sfExpiration) &&
(node().sleOffer->getFieldU32 (sfExpiration) <=
view().parentCloseTime()))
{
// Offer is expired.
WriteLog (lsTRACE, RippleCalc)
<< "advanceNode: expired offer";
rippleCalc_.permanentlyUnfundedOffers_.insert(
node().offerIndex_);
continue;
}
if (node().saTakerPays <= zero || node().saTakerGets <= zero)
{
// Offer has bad amounts. Offers should never have a bad
// amounts.
auto const index = node().offerIndex_;
if (bReverse)
{
// Past internal error, offer had bad amounts.
// This has occurred in production.
WriteLog (lsWARNING, RippleCalc)
<< "advanceNode: PAST INTERNAL ERROR"
<< " REVERSE: OFFER NON-POSITIVE:"
<< " node.saTakerPays=" << node().saTakerPays
<< " node.saTakerGets=" << node().saTakerGets;
// Mark offer for always deletion.
rippleCalc_.permanentlyUnfundedOffers_.insert (
node().offerIndex_);
}
else if (rippleCalc_.permanentlyUnfundedOffers_.find (index)
!= rippleCalc_.permanentlyUnfundedOffers_.end ())
{
// Past internal error, offer was found failed to place
// this in permanentlyUnfundedOffers_.
// Just skip it. It will be deleted.
WriteLog (lsDEBUG, RippleCalc)
<< "advanceNode: PAST INTERNAL ERROR "
<< " FORWARD CONFIRM: OFFER NON-POSITIVE:"
<< " node.saTakerPays=" << node().saTakerPays
<< " node.saTakerGets=" << node().saTakerGets;
}
else
{
// Reverse should have previously put bad offer in list.
// An internal error previously left a bad offer.
WriteLog (lsWARNING, RippleCalc)
<< "advanceNode: INTERNAL ERROR"
<<" FORWARD NEWLY FOUND: OFFER NON-POSITIVE:"
<< " node.saTakerPays=" << node().saTakerPays
<< " node.saTakerGets=" << node().saTakerGets;
// Don't process at all, things are in an unexpected
// state for this transactions.
resultCode = tefEXCEPTION;
}
continue;
}
// Allowed to access source from this node?
//
// XXX This can get called multiple times for same source in a
// row, caching result would be nice.
//
// XXX Going forward could we fund something with a worse
// quality which was previously skipped? Might need to check
// quality.
auto itForward = pathState_.forward().find (accountIssue);
const bool bFoundForward =
itForward != pathState_.forward().end ();
// Only allow a source to be used once, in the first node
// encountered from initial path scan. This prevents
// conflicting uses of the same balance when going reverse vs
// forward.
if (bFoundForward &&
itForward->second != nodeIndex_ &&
node().offerOwnerAccount_ != node().issue_.account)
{
// Temporarily unfunded. Another node uses this source,
// ignore in this offer.
WriteLog (lsTRACE, RippleCalc)
<< "advanceNode: temporarily unfunded offer"
<< " (forward)";
continue;
}
// This is overly strict. For contributions to past. We should
// only count source if actually used.
auto itReverse = pathState_.reverse().find (accountIssue);
bool bFoundReverse = itReverse != pathState_.reverse().end ();
// For this quality increment, only allow a source to be used
// from a single node, in the first node encountered from
// applying offers in reverse.
if (bFoundReverse &&
itReverse->second != nodeIndex_ &&
node().offerOwnerAccount_ != node().issue_.account)
{
// Temporarily unfunded. Another node uses this source,
// ignore in this offer.
WriteLog (lsTRACE, RippleCalc)
<< "advanceNode: temporarily unfunded offer"
<<" (reverse)";
continue;
}
// Determine if used in past.
// We only need to know if it might need to be marked unfunded.
auto itPast = rippleCalc_.mumSource_.find (accountIssue);
bool bFoundPast = (itPast != rippleCalc_.mumSource_.end ());
// Only the current node is allowed to use the source.
node().saOfferFunds = accountFunds(view(),
node().offerOwnerAccount_,
node().saTakerGets,
fhZERO_IF_FROZEN,
getConfig());
// Funds held.
if (node().saOfferFunds <= zero)
{
// Offer is unfunded.
WriteLog (lsTRACE, RippleCalc)
<< "advanceNode: unfunded offer";
if (bReverse && !bFoundReverse && !bFoundPast)
{
// Never mentioned before, clearly just: found unfunded.
// That is, even if this offer fails due to fill or kill
// still do deletions.
// Mark offer for always deletion.
rippleCalc_.permanentlyUnfundedOffers_.insert (node().offerIndex_);
}
else
{
// Moving forward, don't need to insert again
// Or, already found it.
}
// YYY Could verify offer is correct place for unfundeds.
continue;
}
if (bReverse // Need to remember reverse mention.
&& !bFoundPast // Not mentioned in previous passes.
&& !bFoundReverse) // New to pass.
{
// Consider source mentioned by current path state.
WriteLog (lsTRACE, RippleCalc)
<< "advanceNode: remember="
<< node().offerOwnerAccount_
<< "/"
<< node().issue_;
pathState_.insertReverse (accountIssue, nodeIndex_);
}
node().bFundsDirty = false;
node().bEntryAdvance = false;
}
}
}
while (resultCode == tesSUCCESS &&
(node().bEntryAdvance || node().directory.advanceNeeded));
if (resultCode == tesSUCCESS)
{
WriteLog (lsTRACE, RippleCalc)
<< "advanceNode: node.offerIndex_=" << node().offerIndex_;
}
else
{
WriteLog (lsDEBUG, RippleCalc)
<< "advanceNode: resultCode=" << transToken (resultCode);
}
return resultCode;
}
TER PathCursor::reverseLiquidityForAccount () const
{
TER terResult = tesSUCCESS;
auto const lastNodeIndex = nodeSize () - 1;
auto const isFinalNode = (nodeIndex_ == lastNodeIndex);
// 0 quality means none has yet been determined.
std::uint64_t uRateMax = 0;
// Current is allowed to redeem to next.
const bool previousNodeIsAccount = !nodeIndex_ ||
previousNode().isAccount();
const bool nextNodeIsAccount = isFinalNode || nextNode().isAccount();
AccountID const& previousAccountID = previousNodeIsAccount
? previousNode().account_ : node().account_;
AccountID const& nextAccountID = nextNodeIsAccount ? nextNode().account_
: node().account_; // Offers are always issue.
// This is the quality from from the previous node to this one.
auto const qualityIn
= (nodeIndex_ != 0)
? quality_in (view(),
node().account_,
previousAccountID,
node().issue_.currency)
: parityRate;
// And this is the quality from the next one to this one.
auto const qualityOut
= (nodeIndex_ != lastNodeIndex)
? quality_out (view(),
node().account_,
nextAccountID,
node().issue_.currency)
: parityRate;
// For previousNodeIsAccount:
// Previous account is already owed.
const STAmount saPrvOwed = (previousNodeIsAccount && nodeIndex_ != 0)
? creditBalance (view(),
node().account_,
previousAccountID,
node().issue_.currency)
: STAmount (node().issue_);
// The limit amount that the previous account may owe.
const STAmount saPrvLimit = (previousNodeIsAccount && nodeIndex_ != 0)
? creditLimit (view(),
node().account_,
previousAccountID,
node().issue_.currency)
: STAmount (node().issue_);
// Next account is owed.
const STAmount saNxtOwed = (nextNodeIsAccount && nodeIndex_ != lastNodeIndex)
? creditBalance (view(),
node().account_,
nextAccountID,
node().issue_.currency)
: STAmount (node().issue_);
JLOG (j_.trace())
<< "reverseLiquidityForAccount>"
<< " nodeIndex_=" << nodeIndex_ << "/" << lastNodeIndex
<< " previousAccountID=" << previousAccountID
<< " node.account_=" << node().account_
<< " nextAccountID=" << nextAccountID
<< " currency=" << node().issue_.currency
<< " qualityIn=" << qualityIn
<< " qualityOut=" << qualityOut
<< " saPrvOwed=" << saPrvOwed
<< " saPrvLimit=" << saPrvLimit;
// Requests are computed to be the maximum flow possible.
// Previous can redeem the owed IOUs it holds.
const STAmount saPrvRedeemReq = (saPrvOwed > beast::zero)
? saPrvOwed
: STAmount (saPrvOwed.issue ());
// Previous can issue up to limit minus whatever portion of limit already
// used (not including redeemable amount) - another "maximum flow".
const STAmount saPrvIssueReq = (saPrvOwed < beast::zero)
? saPrvLimit + saPrvOwed : saPrvLimit;
// Precompute these values in case we have an order book.
auto deliverCurrency = previousNode().saRevDeliver.getCurrency ();
const STAmount saPrvDeliverReq (
{deliverCurrency, previousNode().saRevDeliver.getIssuer ()}, -1);
// -1 means unlimited delivery.
// Set to zero, because we're trying to hit the previous node.
auto saCurRedeemAct = node().saRevRedeem.zeroed();
// Track the amount we actually redeem.
auto saCurIssueAct = node().saRevIssue.zeroed();
// For !nextNodeIsAccount
auto saCurDeliverAct = node().saRevDeliver.zeroed();
JLOG (j_.trace())
<< "reverseLiquidityForAccount:"
<< " saPrvRedeemReq:" << saPrvRedeemReq
<< " saPrvIssueReq:" << saPrvIssueReq
<< " previousNode.saRevDeliver:" << previousNode().saRevDeliver
<< " saPrvDeliverReq:" << saPrvDeliverReq
<< " node.saRevRedeem:" << node().saRevRedeem
<< " node.saRevIssue:" << node().saRevIssue
<< " saNxtOwed:" << saNxtOwed;
// VFALCO-FIXME this generates errors
//JLOG (j_.trace()) << pathState_.getJson ();
// Current redeem req can't be more than IOUs on hand.
assert (!node().saRevRedeem || -saNxtOwed >= node().saRevRedeem);
assert (!node().saRevIssue // If not issuing, fine.
|| saNxtOwed >= beast::zero
// saNxtOwed >= 0: Sender not holding next IOUs, saNxtOwed < 0:
// Sender holding next IOUs.
|| -saNxtOwed == node().saRevRedeem);
// If issue req, then redeem req must consume all owed.
if (nodeIndex_ == 0)
{
// ^ --> ACCOUNT --> account|offer
// Nothing to do, there is no previous to adjust.
//
// TODO(tom): we could have skipped all that setup and just left
// or even just never call this whole routine on nodeIndex_ = 0!
}
// The next four cases correspond to the table at the bottom of this Wiki
// page section: https://ripple.com/wiki/Transit_Fees#Implementation
else if (previousNodeIsAccount && nextNodeIsAccount)
{
if (isFinalNode)
{
// account --> ACCOUNT --> $
// Overall deliverable.
const STAmount saCurWantedReq = std::min (
pathState_.outReq() - pathState_.outAct(),
saPrvLimit + saPrvOwed);
auto saCurWantedAct = saCurWantedReq.zeroed ();
JLOG (j_.trace())
<< "reverseLiquidityForAccount: account --> "
<< "ACCOUNT --> $ :"
<< " saCurWantedReq=" << saCurWantedReq;
// Calculate redeem
if (saPrvRedeemReq) // Previous has IOUs to redeem.
{
// Redeem your own IOUs at 1:1
saCurWantedAct = std::min (saPrvRedeemReq, saCurWantedReq);
previousNode().saRevRedeem = saCurWantedAct;
uRateMax = STAmount::uRateOne;
JLOG (j_.trace())
<< "reverseLiquidityForAccount: Redeem at 1:1"
<< " saPrvRedeemReq=" << saPrvRedeemReq
<< " (available) previousNode.saRevRedeem="
<< previousNode().saRevRedeem
<< " uRateMax="
<< amountFromQuality (uRateMax).getText ();
}
else
{
previousNode().saRevRedeem.clear (saPrvRedeemReq);
}
// Calculate issuing.
previousNode().saRevIssue.clear (saPrvIssueReq);
if (saCurWantedReq != saCurWantedAct // Need more.
&& saPrvIssueReq) // Will accept IOUs from previous.
{
// Rate: quality in : 1.0
// If we previously redeemed and this has a poorer rate, this
// won't be included the current increment.
rippleLiquidity (
rippleCalc_,
qualityIn,
parityRate,
saPrvIssueReq,
saCurWantedReq,
previousNode().saRevIssue,
saCurWantedAct,
uRateMax);
JLOG (j_.trace())
<< "reverseLiquidityForAccount: Issuing: Rate: "
<< "quality in : 1.0"
<< " previousNode.saRevIssue:" << previousNode().saRevIssue
<< " saCurWantedAct:" << saCurWantedAct;
}
if (!saCurWantedAct)
{
// Must have processed something.
terResult = tecPATH_DRY;
}
}
else
{
// Not final node.
// account --> ACCOUNT --> account
previousNode().saRevRedeem.clear (saPrvRedeemReq);
previousNode().saRevIssue.clear (saPrvIssueReq);
// redeem (part 1) -> redeem
if (node().saRevRedeem
// Next wants IOUs redeemed from current account.
&& saPrvRedeemReq)
// Previous has IOUs to redeem to the current account.
{
// TODO(tom): add English.
// Rate : 1.0 : quality out - we must accept our own IOUs
// as 1:1.
rippleLiquidity (
rippleCalc_,
parityRate,
qualityOut,
saPrvRedeemReq,
node().saRevRedeem,
previousNode().saRevRedeem,
saCurRedeemAct,
uRateMax);
JLOG (j_.trace())
<< "reverseLiquidityForAccount: "
<< "Rate : 1.0 : quality out"
<< " previousNode.saRevRedeem:" << previousNode().saRevRedeem
<< " saCurRedeemAct:" << saCurRedeemAct;
}
// issue (part 1) -> redeem
if (node().saRevRedeem != saCurRedeemAct
// The current node has more IOUs to redeem.
&& previousNode().saRevRedeem == saPrvRedeemReq)
// The previous node has no IOUs to redeem remaining, so issues.
{
// Rate: quality in : quality out
rippleLiquidity (
rippleCalc_,
qualityIn,
qualityOut,
saPrvIssueReq,
node().saRevRedeem,
previousNode().saRevIssue,
saCurRedeemAct,
uRateMax);
JLOG (j_.trace())
<< "reverseLiquidityForAccount: "
<< "Rate: quality in : quality out:"
<< " previousNode.saRevIssue:" << previousNode().saRevIssue
<< " saCurRedeemAct:" << saCurRedeemAct;
}
// redeem (part 2) -> issue.
if (node().saRevIssue // Next wants IOUs issued.
// TODO(tom): this condition seems redundant.
&& saCurRedeemAct == node().saRevRedeem
// Can only issue if completed redeeming.
&& previousNode().saRevRedeem != saPrvRedeemReq)
// Did not complete redeeming previous IOUs.
{
// Rate : 1.0 : transfer_rate
rippleLiquidity (
rippleCalc_,
parityRate,
transferRate (view(), node().account_),
saPrvRedeemReq,
node().saRevIssue,
previousNode().saRevRedeem,
saCurIssueAct,
uRateMax);
JLOG (j_.debug())
<< "reverseLiquidityForAccount: "
<< "Rate : 1.0 : transfer_rate:"
<< " previousNode.saRevRedeem:" << previousNode().saRevRedeem
<< " saCurIssueAct:" << saCurIssueAct;
}
// issue (part 2) -> issue
if (node().saRevIssue != saCurIssueAct
// Need wants more IOUs issued.
&& saCurRedeemAct == node().saRevRedeem
// Can only issue if completed redeeming.
&& saPrvRedeemReq == previousNode().saRevRedeem
// Previously redeemed all owed IOUs.
&& saPrvIssueReq)
// Previous can issue.
{
// Rate: quality in : 1.0
rippleLiquidity (
rippleCalc_,
qualityIn,
parityRate,
saPrvIssueReq,
node().saRevIssue,
previousNode().saRevIssue,
saCurIssueAct,
uRateMax);
JLOG (j_.trace())
<< "reverseLiquidityForAccount: "
<< "Rate: quality in : 1.0:"
<< " previousNode.saRevIssue:" << previousNode().saRevIssue
<< " saCurIssueAct:" << saCurIssueAct;
}
if (!saCurRedeemAct && !saCurIssueAct)
{
// Did not make progress.
terResult = tecPATH_DRY;
}
JLOG (j_.trace())
<< "reverseLiquidityForAccount: "
<< "^|account --> ACCOUNT --> account :"
<< " node.saRevRedeem:" << node().saRevRedeem
<< " node.saRevIssue:" << node().saRevIssue
<< " saPrvOwed:" << saPrvOwed
<< " saCurRedeemAct:" << saCurRedeemAct
<< " saCurIssueAct:" << saCurIssueAct;
}
}
else if (previousNodeIsAccount && !nextNodeIsAccount)
{
// account --> ACCOUNT --> offer
// Note: deliver is always issue as ACCOUNT is the issuer for the offer
// input.
JLOG (j_.trace())
<< "reverseLiquidityForAccount: "
<< "account --> ACCOUNT --> offer";
previousNode().saRevRedeem.clear (saPrvRedeemReq);
previousNode().saRevIssue.clear (saPrvIssueReq);
// We have three cases: the nxt offer can be owned by current account,
// previous account or some third party account.
//
// Also, the current account may or may not have a redeemable balance
// with the account for the next offer, so we don't yet know if we're
// redeeming or issuing.
//
// TODO(tom): Make sure deliver was cleared, or check actual is zero.
// redeem -> deliver/issue.
if (saPrvOwed > beast::zero // Previous has IOUs to redeem.
&& node().saRevDeliver) // Need some issued.
{
// Rate : 1.0 : transfer_rate
rippleLiquidity (
rippleCalc_,
parityRate,
transferRate (view(), node().account_),
saPrvRedeemReq,
node().saRevDeliver,
previousNode().saRevRedeem,
saCurDeliverAct,
uRateMax);
}
// issue -> deliver/issue
if (saPrvRedeemReq == previousNode().saRevRedeem
// Previously redeemed all owed.
&& node().saRevDeliver != saCurDeliverAct) // Still need some issued.
{
// Rate: quality in : 1.0
rippleLiquidity (
rippleCalc_,
qualityIn,
parityRate,
saPrvIssueReq,
node().saRevDeliver,
previousNode().saRevIssue,
saCurDeliverAct,
uRateMax);
}
if (!saCurDeliverAct)
{
// Must want something.
terResult = tecPATH_DRY;
}
JLOG (j_.trace())
<< "reverseLiquidityForAccount: "
<< " node.saRevDeliver:" << node().saRevDeliver
<< " saCurDeliverAct:" << saCurDeliverAct
<< " saPrvOwed:" << saPrvOwed;
}
else if (!previousNodeIsAccount && nextNodeIsAccount)
{
if (isFinalNode)
{
// offer --> ACCOUNT --> $
// Previous is an offer, no limit: redeem own IOUs.
//
// This is the final node; we can't look to the right to get values;
// we have to go up to get the out value for the entire path state.
STAmount const& saCurWantedReq =
pathState_.outReq() - pathState_.outAct();
STAmount saCurWantedAct = saCurWantedReq.zeroed();
JLOG (j_.trace())
<< "reverseLiquidityForAccount: "
<< "offer --> ACCOUNT --> $ :"
<< " saCurWantedReq:" << saCurWantedReq
<< " saOutAct:" << pathState_.outAct()
<< " saOutReq:" << pathState_.outReq();
if (saCurWantedReq <= beast::zero)
{
assert(false);
JLOG (j_.fatal()) << "CurWantReq was not positive";
return tefEXCEPTION;
}
// The previous node is an offer; we are receiving our own currency.
// The previous order book's entries might hold our issuances; might
// not hold our issuances; might be our own offer.
//
// Assume the worst case, the case which costs the most to go
// through, which is that it is not our own offer or our own
// issuances. Later on the forward pass we may be able to do
// better.
//
// TODO: this comment applies generally to this section - move it up
// to a document.
// Rate: quality in : 1.0
rippleLiquidity (
rippleCalc_,
qualityIn,
parityRate,
saPrvDeliverReq,
saCurWantedReq,
previousNode().saRevDeliver,
saCurWantedAct,
uRateMax);
if (!saCurWantedAct)
{
// Must have processed something.
terResult = tecPATH_DRY;
}
JLOG (j_.trace())
<< "reverseLiquidityForAccount:"
<< " previousNode().saRevDeliver:" << previousNode().saRevDeliver
<< " saPrvDeliverReq:" << saPrvDeliverReq
<< " saCurWantedAct:" << saCurWantedAct
<< " saCurWantedReq:" << saCurWantedReq;
}
else
{
// offer --> ACCOUNT --> account
// Note: offer is always delivering(redeeming) as account is issuer.
JLOG (j_.trace())
<< "reverseLiquidityForAccount: "
<< "offer --> ACCOUNT --> account :"
<< " node.saRevRedeem:" << node().saRevRedeem
<< " node.saRevIssue:" << node().saRevIssue;
// deliver -> redeem
// TODO(tom): now we have more checking in nodeRipple, these checks
// might be redundant.
if (node().saRevRedeem) // Next wants us to redeem.
{
// cur holds IOUs from the account to the right, the nxt
// account. If someone is making the current account get rid of
// the nxt account's IOUs, then charge the input for quality
// out.
//
// Rate : 1.0 : quality out
rippleLiquidity (
rippleCalc_,
parityRate,
qualityOut,
saPrvDeliverReq,
node().saRevRedeem,
previousNode().saRevDeliver,
saCurRedeemAct,
uRateMax);
}
// deliver -> issue.
if (node().saRevRedeem == saCurRedeemAct
// Can only issue if previously redeemed all.
&& node().saRevIssue)
// Need some issued.
{
// Rate : 1.0 : transfer_rate
rippleLiquidity (
rippleCalc_,
parityRate,
transferRate (view(), node().account_),
saPrvDeliverReq,
node().saRevIssue,
previousNode().saRevDeliver,
saCurIssueAct,
uRateMax);
}
JLOG (j_.trace())
<< "reverseLiquidityForAccount:"
<< " saCurRedeemAct:" << saCurRedeemAct
<< " node.saRevRedeem:" << node().saRevRedeem
<< " previousNode.saRevDeliver:" << previousNode().saRevDeliver
<< " node.saRevIssue:" << node().saRevIssue;
if (!previousNode().saRevDeliver)
{
// Must want something.
terResult = tecPATH_DRY;
}
}
}
else
{
// offer --> ACCOUNT --> offer
// deliver/redeem -> deliver/issue.
JLOG (j_.trace())
<< "reverseLiquidityForAccount: offer --> ACCOUNT --> offer";
// Rate : 1.0 : transfer_rate
rippleLiquidity (
rippleCalc_,
parityRate,
transferRate (view(), node().account_),
saPrvDeliverReq,
node().saRevDeliver,
previousNode().saRevDeliver,
saCurDeliverAct,
uRateMax);
if (!saCurDeliverAct)
{
// Must want something.
terResult = tecPATH_DRY;
}
}
return terResult;
}
