| 370 | } |
| 371 | |
| 372 | bool CheckSequenceLocks(const CTransaction &tx, int flags, LockPoints* lp, bool useExistingLockPoints) |
| 373 | { |
| 374 | AssertLockHeld(cs_main); |
| 375 | AssertLockHeld(mempool.cs); |
| 376 | |
| 377 | CBlockIndex* tip = chainActive.Tip(); |
| 378 | assert(tip != nullptr); |
| 379 | |
| 380 | CBlockIndex index; |
| 381 | index.pprev = tip; |
| 382 | // CheckSequenceLocks() uses chainActive.Height()+1 to evaluate |
| 383 | // height based locks because when SequenceLocks() is called within |
| 384 | // ConnectBlock(), the height of the block *being* |
| 385 | // evaluated is what is used. |
| 386 | // Thus if we want to know if a transaction can be part of the |
| 387 | // *next* block, we need to use one more than chainActive.Height() |
| 388 | index.nHeight = tip->nHeight + 1; |
| 389 | |
| 390 | std::pair<int, int64_t> lockPair; |
| 391 | if (useExistingLockPoints) { |
| 392 | assert(lp); |
| 393 | lockPair.first = lp->height; |
| 394 | lockPair.second = lp->time; |
| 395 | } |
| 396 | else { |
| 397 | // pcoinsTip contains the UTXO set for chainActive.Tip() |
| 398 | CCoinsViewMemPool viewMemPool(pcoinsTip.get(), mempool); |
| 399 | std::vector<int> prevheights; |
| 400 | prevheights.resize(tx.vin.size()); |
| 401 | for (size_t txinIndex = 0; txinIndex < tx.vin.size(); txinIndex++) { |
| 402 | const CTxIn& txin = tx.vin[txinIndex]; |
| 403 | Coin coin; |
| 404 | if (!viewMemPool.GetCoin(txin.prevout, coin)) { |
| 405 | return error("%s: Missing input", __func__); |
| 406 | } |
| 407 | if (coin.nHeight == MEMPOOL_HEIGHT) { |
| 408 | // Assume all mempool transaction confirm in the next block |
| 409 | prevheights[txinIndex] = tip->nHeight + 1; |
| 410 | } else { |
| 411 | prevheights[txinIndex] = coin.nHeight; |
| 412 | } |
| 413 | } |
| 414 | lockPair = CalculateSequenceLocks(tx, flags, &prevheights, index); |
| 415 | if (lp) { |
| 416 | lp->height = lockPair.first; |
| 417 | lp->time = lockPair.second; |
| 418 | // Also store the hash of the block with the highest height of |
| 419 | // all the blocks which have sequence locked prevouts. |
| 420 | // This hash needs to still be on the chain |
| 421 | // for these LockPoint calculations to be valid |
| 422 | // Note: It is impossible to correctly calculate a maxInputBlock |
| 423 | // if any of the sequence locked inputs depend on unconfirmed txs, |
| 424 | // except in the special case where the relative lock time/height |
| 425 | // is 0, which is equivalent to no sequence lock. Since we assume |
| 426 | // input height of tip+1 for mempool txs and test the resulting |
| 427 | // lockPair from CalculateSequenceLocks against tip+1. We know |
| 428 | // EvaluateSequenceLocks will fail if there was a non-zero sequence |
| 429 | // lock on a mempool input, so we can use the return value of |