/** Returns the hash of the specified ledger.
@param ledgerIndex The index of the desired ledger.
@param referenceLedger [out] An optional known good subsequent ledger.
@return The hash of the ledger. This will be all-bits-zero if not found.
*/
LedgerHash getHash(
LedgerIndex const& ledgerIndex,
std::shared_ptr<ReadView const>& referenceLedger)
{
LedgerHash ledgerHash;
if (!referenceLedger || (referenceLedger->info().seq < ledgerIndex))
{
referenceLedger = app_.getLedgerMaster().getValidatedLedger();
if (!referenceLedger)
{
JLOG (j_.warn()) << "No validated ledger";
return ledgerHash; // Nothing we can do. No validated ledger.
}
}
if (referenceLedger->info().seq >= ledgerIndex)
{
// See if the hash for the ledger we need is in the reference ledger
ledgerHash = getLedgerHash(referenceLedger, ledgerIndex);
if (ledgerHash.isZero())
{
// No. Try to get another ledger that might have the hash we
// need: compute the index and hash of a ledger that will have
// the hash we need.
LedgerIndex refIndex = getCandidateLedger (ledgerIndex);
LedgerHash refHash = getLedgerHash (referenceLedger, refIndex);
bool const nonzero (refHash.isNonZero ());
assert (nonzero);
if (nonzero)
{
// We found the hash and sequence of a better reference
// ledger.
referenceLedger =
app_.getInboundLedgers().acquire(
refHash, refIndex, InboundLedger::fcGENERIC);
if (referenceLedger)
ledgerHash = getLedgerHash(
referenceLedger, ledgerIndex);
}
}
}
else
JLOG (j_.warn()) << "Validated ledger is prior to target ledger";
return ledgerHash;
}
/** Returns the hash of the specified ledger.
@param ledgerIndex The index of the desired ledger.
@param referenceLedger [out] An optional known good subsequent ledger.
@return The hash of the ledger. This will be all-bits-zero if not found.
*/
LedgerHash getHash(
LedgerIndex const& ledgerIndex,
Ledger::pointer& referenceLedger)
{
LedgerHash ledgerHash;
if (!referenceLedger || (referenceLedger->getLedgerSeq() < ledgerIndex))
{
referenceLedger = getApp().getLedgerMaster().getValidatedLedger();
if (!referenceLedger)
{
m_journal.warning << "No validated ledger";
return ledgerHash; // Nothing we can do. No validated ledger.
}
}
if (referenceLedger->getLedgerSeq() >= ledgerIndex)
{
// See if the hash for the ledger we need is in the reference ledger
ledgerHash = getLedgerHash(referenceLedger, ledgerIndex);
if (ledgerHash.isZero())
{
// No, Try to get another ledger that might have the hash we need
// Compute the index and hash of a ledger that will have the hash we need
LedgerIndex refIndex = getCandidateLedger (ledgerIndex);
LedgerHash refHash = getLedgerHash (referenceLedger, refIndex);
bool const nonzero (refHash.isNonZero ());
assert (nonzero);
if (nonzero)
{
// We found the hash and sequence of a better reference ledger
referenceLedger =
getApp().getInboundLedgers().acquire(
refHash, refIndex, InboundLedger::fcGENERIC);
if (referenceLedger)
ledgerHash = getLedgerHash(referenceLedger, ledgerIndex);
}
}
}
else
m_journal.warning << "Validated ledger is prior to target ledger";
return ledgerHash;
}
// {
// ledger_hash : <ledger>
// ledger_index : <ledger_index>
// }
Json::Value doLedgerRequest (RPC::Context& context)
{
auto const hasHash = context.params.isMember (jss::ledger_hash);
auto const hasIndex = context.params.isMember (jss::ledger_index);
auto& ledgerMaster = getApp().getLedgerMaster();
LedgerHash ledgerHash;
if ((hasHash && hasIndex) || !(hasHash || hasIndex))
{
return RPC::make_param_error(
"Exactly one of ledger_hash and ledger_index can be set.");
}
if (hasHash)
{
auto const& jsonHash = context.params[jss::ledger_hash];
if (!jsonHash.isString() || !ledgerHash.SetHex (jsonHash.asString ()))
return RPC::invalid_field_message (jss::ledger_hash);
} else {
auto const& jsonIndex = context.params[jss::ledger_index];
if (!jsonIndex.isNumeric ())
return RPC::invalid_field_message (jss::ledger_index);
// We need a validated ledger to get the hash from the sequence
if (ledgerMaster.getValidatedLedgerAge() > 120)
return rpcError (rpcNO_CURRENT);
auto ledgerIndex = jsonIndex.asInt();
auto ledger = ledgerMaster.getValidatedLedger();
if (ledgerIndex >= ledger->getLedgerSeq())
return RPC::make_param_error("Ledger index too large");
// Try to get the hash of the desired ledger from the validated ledger
ledgerHash = ledger->getLedgerHash (ledgerIndex);
if (ledgerHash == zero)
{
// Find a ledger more likely to have the hash of the desired ledger
auto refIndex = (ledgerIndex + 255) & (~255);
auto refHash = ledger->getLedgerHash (refIndex);
assert (refHash.isNonZero ());
ledger = ledgerMaster.getLedgerByHash (refHash);
if (!ledger)
{
// We don't have the ledger we need to figure out which ledger
// they want. Try to get it.
if (auto il = getApp().getInboundLedgers().acquire (
refHash, refIndex, InboundLedger::fcGENERIC))
return getJson (LedgerFill (*il));
if (auto il = getApp().getInboundLedgers().find (refHash))
{
Json::Value jvResult = il->getJson (0);
jvResult[jss::error] = "ledgerNotFound";
return jvResult;
}
// Likely the app is shutting down
return Json::Value();
}
ledgerHash = ledger->getLedgerHash (ledgerIndex);
assert (ledgerHash.isNonZero ());
}
}
auto ledger = ledgerMaster.getLedgerByHash (ledgerHash);
if (ledger)
{
// We already have the ledger they want
Json::Value jvResult;
jvResult[jss::ledger_index] = ledger->getLedgerSeq();
addJson (jvResult, {*ledger, 0});
return jvResult;
}
else
{
// Try to get the desired ledger
if (auto il = getApp ().getInboundLedgers ().acquire (
ledgerHash, 0, InboundLedger::fcGENERIC))
return getJson (LedgerFill (*il));
if (auto il = getApp().getInboundLedgers().find (ledgerHash))
return il->getJson (0);
return RPC::make_error (
rpcNOT_READY, "findCreate failed to return an inbound ledger");
}
}