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Update code to match current pull request.

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Mark Friedenbach 2015-10-05 15:37:23 -07:00
parent ec540ce6ed
commit 1ed68dc605
1 changed files with 52 additions and 19 deletions
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bip-0068.mediawiki
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@ -52,7 +52,7 @@ This is proposed to be accomplished by replacing IsFinalTx() and CheckFinalTx(),
{
CCoins coins;
bool fEnforceBIP68 = tx.nVersion >= 2
bool fEnforceBIP68 = static_cast<uint32_t>(tx.nVersion) >= 2
&& flags & LOCKTIME_VERIFY_SEQUENCE;
// Will be set to the equivalent height- and time-based nLockTime
@ -72,8 +72,9 @@ This is proposed to be accomplished by replacing IsFinalTx() and CheckFinalTx(),
fFinalized = false;
// Do not enforce sequence numbers as a relative lock time
// unless we have been instructed to.
if (!fEnforceBIP68)
// unless we have been instructed to, and a view has been
// provided.
if (!(fEnforceBIP68 && pCoinsView))
continue;
// Sequence numbers equal to or above the locktime threshold
@ -82,31 +83,62 @@ This is proposed to be accomplished by replacing IsFinalTx() and CheckFinalTx(),
if (txin.nSequence >= CTxIn::SEQUENCE_LOCKTIME_THRESHOLD)
continue;
// Skip this input if it is not in the UTXO set. Aside from
// the coinbase input, this should only ever happen in non-
// consensus code.
if (!pCoinsView->GetCoins(txin.prevout.hash, coins))
// Fetch the UTXO corresponding to this input.
if (!pCoinsView->GetCoins(txin.prevout.hash, coins)) {
// It is fully expected that coinbases inputs are not
// found in the UTXO set. Proceed to the next intput...
if (txin.prevout.IsNull())
continue;
// If a non-coinbase input cannot be found, we cannot
// be certain about whether lock-time constraints have
// been satisfied. Note that it should only ever be
// possible for this to happen with wallet transactions
// that have unknown inputs.
else
return std::numeric_limits<int64_t>::max();
}
if (txin.nSequence < CTxIn::SEQUENCE_UNITS_THRESHOLD)
// coins.nHeight is MEMPOOL_HEIGHT (an absurdly high value)
// if the parent transaction was from the mempool. We can't
// know what height it will have once confirmed, but we
// assume it makes it in the same block.
int nCoinHeight = std::min(coins.nHeight, nBlockHeight);
if (txin.nSequence < CTxIn::SEQUENCE_UNITS_THRESHOLD) {
// We subtract 1 from relative lock-times because a lock-
// time of 0 has the semantics of "same block," so a lock-
// time of 1 should mean "next block," but nLockTime has
// the semantics of "last invalid block height."
nMinHeight = std::max(nMinHeight,
coins.nHeight
+ (int)(txin.nSequence >> CTxIn::SEQUENCE_BLOCKS_OFFSET)
- 1);
else
nMinHeight = std::max(nMinHeight, nCoinHeight + (int)(
txin.nSequence >> CTxIn::SEQUENCE_BLOCKS_OFFSET) - 1);
} else {
// In two locations that follow we make reference to
// chainActive.Tip(). To prevent a race condition, we
// store a reference to the current tip.
//
// Note that it is not guaranteed that indexBestBlock will
// be consistent with the passed in view. The proper thing
// to do is to have the view return time information about
// UTXOs.
const CBlockIndex& indexBestBlock = *chainActive.Tip();
// The only time the negative branch of this conditional
// is executed is when the prior output was taken from the
// mempool, in which case we assume it makes it into the
// same block (see above).
int64_t nCoinTime = (nCoinHeight <= (indexBestBlock.nHeight+1))
? indexBestBlock.GetAncestor(nCoinHeight-1)->GetMedianTimePast()
: nBlockTime;
// Time-based relative lock-times are measured from the
// smallest allowed timestamp of the block containing the
// txout being spent, which is the median time past of the
// block prior. We subtract one for the same reason as
// above.
nMinTime = std::max(nMinTime,
pindexBestHeader->GetAncestor(coins.nHeight-1)->GetMedianTimePast()
+ (int64_t)((txin.nSequence ^ CTxIn::SEQUENCE_UNITS_THRESHOLD) >> CTxIn::SEQUENCE_SECONDS_OFFSET)
- 1);
nMinTime = std::max(nMinTime, nCoinTime + (int64_t)((
txin.nSequence - CTxIn::SEQUENCE_UNITS_THRESHOLD)
>> CTxIn::SEQUENCE_SECONDS_OFFSET) - 1);
}
}
// If all sequence numbers are CTxIn::SEQUENCE_FINAL, the
@ -137,7 +169,8 @@ This is proposed to be accomplished by replacing IsFinalTx() and CheckFinalTx(),
flags = std::max(flags, 0);
// pcoinsTip contains the UTXO set for chainActive.Tip()
const CCoinsView *pCoinsView = pcoinsTip;
CCoinsViewMemPool viewMemPool(pcoinsTip, mempool);
const CCoinsView *pCoinsView = &viewMemPool;
// CheckLockTime() uses chainActive.Height()+1 to evaluate
// nLockTime because when LockTime() is called within