Ejemplo n.º 1
0
// BenchmarkIsCoinBaseTx performs a simple benchmark against the IsCoinBaseTx
// function.
func BenchmarkIsCoinBaseTx(b *testing.B) {
	tx := Block100000.Transactions[1]
	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		blockchain.IsCoinBaseTx(tx)
	}
}
Ejemplo n.º 2
0
// chainSyncer is a goroutine dedicated to processing new blocks in order to
// keep the wallet's utxo state up to date.
//
// NOTE: This MUST be run as a goroutine.
func (m *memWallet) chainSyncer() {
	var update *chainUpdate

	for range m.chainUpdateSignal {
		// A new update is available, so pop the new chain update from
		// the front of the update queue.
		m.chainMtx.Lock()
		update = m.chainUpdates[0]
		m.chainUpdates[0] = nil // Set to nil to prevent GC leak.
		m.chainUpdates = m.chainUpdates[1:]
		m.chainMtx.Unlock()

		// Fetch the new block so we can process it shortly below.
		block, err := m.rpc.GetBlock(update.blockHash)
		if err != nil {
			return
		}

		// Update the latest synced height, then process each
		// transaction in the block creating and destroying utxos
		// within the wallet as a result.
		m.Lock()
		m.currentHeight = update.blockHeight
		undo := &undoEntry{
			utxosDestroyed: make(map[wire.OutPoint]*utxo),
		}
		for _, mtx := range block.Transactions {
			isCoinbase := blockchain.IsCoinBaseTx(mtx)
			txHash := mtx.TxHash()
			m.evalOutputs(mtx.TxOut, &txHash, isCoinbase, undo)
			m.evalInputs(mtx.TxIn, undo)
		}

		// Finally, record the undo entry for this block so we can
		// properly update our internal state in response to the block
		// being re-org'd from the main chain.
		m.reorgJournal[update.blockHeight] = undo
		m.Unlock()
	}
}
Ejemplo n.º 3
0
func (s *Store) unspentOutputs(ns walletdb.Bucket) ([]Credit, error) {
	var unspent []Credit

	var op wire.OutPoint
	var block Block
	err := ns.Bucket(bucketUnspent).ForEach(func(k, v []byte) error {
		err := readCanonicalOutPoint(k, &op)
		if err != nil {
			return err
		}
		if existsRawUnminedInput(ns, k) != nil {
			// Output is spent by an unmined transaction.
			// Skip this k/v pair.
			return nil
		}
		err = readUnspentBlock(v, &block)
		if err != nil {
			return err
		}

		blockTime, err := fetchBlockTime(ns, block.Height)
		if err != nil {
			return err
		}
		// TODO(jrick): reading the entire transaction should
		// be avoidable.  Creating the credit only requires the
		// output amount and pkScript.
		rec, err := fetchTxRecord(ns, &op.Hash, &block)
		if err != nil {
			return err
		}
		txOut := rec.MsgTx.TxOut[op.Index]
		cred := Credit{
			OutPoint: op,
			BlockMeta: BlockMeta{
				Block: block,
				Time:  blockTime,
			},
			Amount:       btcutil.Amount(txOut.Value),
			PkScript:     txOut.PkScript,
			Received:     rec.Received,
			FromCoinBase: blockchain.IsCoinBaseTx(&rec.MsgTx),
		}
		unspent = append(unspent, cred)
		return nil
	})
	if err != nil {
		if _, ok := err.(Error); ok {
			return nil, err
		}
		str := "failed iterating unspent bucket"
		return nil, storeError(ErrDatabase, str, err)
	}

	err = ns.Bucket(bucketUnminedCredits).ForEach(func(k, v []byte) error {
		if existsRawUnminedInput(ns, k) != nil {
			// Output is spent by an unmined transaction.
			// Skip to next unmined credit.
			return nil
		}

		err := readCanonicalOutPoint(k, &op)
		if err != nil {
			return err
		}

		// TODO(jrick): Reading/parsing the entire transaction record
		// just for the output amount and script can be avoided.
		recVal := existsRawUnmined(ns, op.Hash[:])
		var rec TxRecord
		err = readRawTxRecord(&op.Hash, recVal, &rec)
		if err != nil {
			return err
		}

		txOut := rec.MsgTx.TxOut[op.Index]
		cred := Credit{
			OutPoint: op,
			BlockMeta: BlockMeta{
				Block: Block{Height: -1},
			},
			Amount:       btcutil.Amount(txOut.Value),
			PkScript:     txOut.PkScript,
			Received:     rec.Received,
			FromCoinBase: blockchain.IsCoinBaseTx(&rec.MsgTx),
		}
		unspent = append(unspent, cred)
		return nil
	})
	if err != nil {
		if _, ok := err.(Error); ok {
			return nil, err
		}
		str := "failed iterating unmined credits bucket"
		return nil, storeError(ErrDatabase, str, err)
	}

	return unspent, nil
}
Ejemplo n.º 4
0
func (s *Store) balance(ns walletdb.Bucket, minConf int32, syncHeight int32) (btcutil.Amount, error) {
	bal, err := fetchMinedBalance(ns)
	if err != nil {
		return 0, err
	}

	// Subtract the balance for each credit that is spent by an unmined
	// transaction.
	var op wire.OutPoint
	var block Block
	err = ns.Bucket(bucketUnspent).ForEach(func(k, v []byte) error {
		err := readCanonicalOutPoint(k, &op)
		if err != nil {
			return err
		}
		err = readUnspentBlock(v, &block)
		if err != nil {
			return err
		}
		if existsRawUnminedInput(ns, k) != nil {
			_, v := existsCredit(ns, &op.Hash, op.Index, &block)
			amt, err := fetchRawCreditAmount(v)
			if err != nil {
				return err
			}
			bal -= amt
		}
		return nil
	})
	if err != nil {
		if _, ok := err.(Error); ok {
			return 0, err
		}
		str := "failed iterating unspent outputs"
		return 0, storeError(ErrDatabase, str, err)
	}

	// Decrement the balance for any unspent credit with less than
	// minConf confirmations and any (unspent) immature coinbase credit.
	stopConf := minConf
	if blockchain.CoinbaseMaturity > stopConf {
		stopConf = blockchain.CoinbaseMaturity
	}
	lastHeight := syncHeight - stopConf
	blockIt := makeReverseBlockIterator(ns)
	for blockIt.prev() {
		block := &blockIt.elem

		if block.Height < lastHeight {
			break
		}

		for i := range block.transactions {
			txHash := &block.transactions[i]
			rec, err := fetchTxRecord(ns, txHash, &block.Block)
			if err != nil {
				return 0, err
			}
			numOuts := uint32(len(rec.MsgTx.TxOut))
			for i := uint32(0); i < numOuts; i++ {
				// Avoid double decrementing the credit amount
				// if it was already removed for being spent by
				// an unmined tx.
				opKey := canonicalOutPoint(txHash, i)
				if existsRawUnminedInput(ns, opKey) != nil {
					continue
				}

				_, v := existsCredit(ns, txHash, i, &block.Block)
				if v == nil {
					continue
				}
				amt, spent, err := fetchRawCreditAmountSpent(v)
				if err != nil {
					return 0, err
				}
				if spent {
					continue
				}
				confs := syncHeight - block.Height + 1
				if confs < minConf || (blockchain.IsCoinBaseTx(&rec.MsgTx) &&
					confs < blockchain.CoinbaseMaturity) {
					bal -= amt
				}
			}
		}
	}
	if blockIt.err != nil {
		return 0, blockIt.err
	}

	// If unmined outputs are included, increment the balance for each
	// output that is unspent.
	if minConf == 0 {
		err = ns.Bucket(bucketUnminedCredits).ForEach(func(k, v []byte) error {
			if existsRawUnminedInput(ns, k) != nil {
				// Output is spent by an unmined transaction.
				// Skip to next unmined credit.
				return nil
			}

			amount, err := fetchRawUnminedCreditAmount(v)
			if err != nil {
				return err
			}
			bal += amount
			return nil
		})
		if err != nil {
			if _, ok := err.(Error); ok {
				return 0, err
			}
			str := "failed to iterate over unmined credits bucket"
			return 0, storeError(ErrDatabase, str, err)
		}
	}

	return bal, nil
}
Ejemplo n.º 5
0
func (s *Store) rollback(ns walletdb.Bucket, height int32) error {
	minedBalance, err := fetchMinedBalance(ns)
	if err != nil {
		return err
	}

	// Keep track of all credits that were removed from coinbase
	// transactions.  After detaching all blocks, if any transaction record
	// exists in unmined that spends these outputs, remove them and their
	// spend chains.
	//
	// It is necessary to keep these in memory and fix the unmined
	// transactions later since blocks are removed in increasing order.
	var coinBaseCredits []wire.OutPoint

	it := makeBlockIterator(ns, height)
	for it.next() {
		b := &it.elem

		log.Infof("Rolling back %d transactions from block %v height %d",
			len(b.transactions), b.Hash, b.Height)

		for i := range b.transactions {
			txHash := &b.transactions[i]

			recKey := keyTxRecord(txHash, &b.Block)
			recVal := existsRawTxRecord(ns, recKey)
			var rec TxRecord
			err = readRawTxRecord(txHash, recVal, &rec)
			if err != nil {
				return err
			}

			err = deleteTxRecord(ns, txHash, &b.Block)
			if err != nil {
				return err
			}

			// Handle coinbase transactions specially since they are
			// not moved to the unconfirmed store.  A coinbase cannot
			// contain any debits, but all credits should be removed
			// and the mined balance decremented.
			if blockchain.IsCoinBaseTx(&rec.MsgTx) {
				op := wire.OutPoint{Hash: rec.Hash}
				for i, output := range rec.MsgTx.TxOut {
					k, v := existsCredit(ns, &rec.Hash,
						uint32(i), &b.Block)
					if v == nil {
						continue
					}
					op.Index = uint32(i)

					coinBaseCredits = append(coinBaseCredits, op)

					unspentKey, credKey := existsUnspent(ns, &op)
					if credKey != nil {
						minedBalance -= btcutil.Amount(output.Value)
						err = deleteRawUnspent(ns, unspentKey)
						if err != nil {
							return err
						}
					}
					err = deleteRawCredit(ns, k)
					if err != nil {
						return err
					}
				}

				continue
			}

			err = putRawUnmined(ns, txHash[:], recVal)
			if err != nil {
				return err
			}

			// For each debit recorded for this transaction, mark
			// the credit it spends as unspent (as long as it still
			// exists) and delete the debit.  The previous output is
			// recorded in the unconfirmed store for every previous
			// output, not just debits.
			for i, input := range rec.MsgTx.TxIn {
				prevOut := &input.PreviousOutPoint
				prevOutKey := canonicalOutPoint(&prevOut.Hash,
					prevOut.Index)
				err = putRawUnminedInput(ns, prevOutKey, rec.Hash[:])
				if err != nil {
					return err
				}

				// If this input is a debit, remove the debit
				// record and mark the credit that it spent as
				// unspent, incrementing the mined balance.
				debKey, credKey, err := existsDebit(ns,
					&rec.Hash, uint32(i), &b.Block)
				if err != nil {
					return err
				}
				if debKey == nil {
					continue
				}

				// unspendRawCredit does not error in case the
				// no credit exists for this key, but this
				// behavior is correct.  Since blocks are
				// removed in increasing order, this credit
				// may have already been removed from a
				// previously removed transaction record in
				// this rollback.
				var amt btcutil.Amount
				amt, err = unspendRawCredit(ns, credKey)
				if err != nil {
					return err
				}
				err = deleteRawDebit(ns, debKey)
				if err != nil {
					return err
				}

				// If the credit was previously removed in the
				// rollback, the credit amount is zero.  Only
				// mark the previously spent credit as unspent
				// if it still exists.
				if amt == 0 {
					continue
				}
				unspentVal, err := fetchRawCreditUnspentValue(credKey)
				if err != nil {
					return err
				}
				minedBalance += amt
				err = putRawUnspent(ns, prevOutKey, unspentVal)
				if err != nil {
					return err
				}
			}

			// For each detached non-coinbase credit, move the
			// credit output to unmined.  If the credit is marked
			// unspent, it is removed from the utxo set and the
			// mined balance is decremented.
			//
			// TODO: use a credit iterator
			for i, output := range rec.MsgTx.TxOut {
				k, v := existsCredit(ns, &rec.Hash, uint32(i),
					&b.Block)
				if v == nil {
					continue
				}

				amt, change, err := fetchRawCreditAmountChange(v)
				if err != nil {
					return err
				}
				outPointKey := canonicalOutPoint(&rec.Hash, uint32(i))
				unminedCredVal := valueUnminedCredit(amt, change)
				err = putRawUnminedCredit(ns, outPointKey, unminedCredVal)
				if err != nil {
					return err
				}

				err = deleteRawCredit(ns, k)
				if err != nil {
					return err
				}

				credKey := existsRawUnspent(ns, outPointKey)
				if credKey != nil {
					minedBalance -= btcutil.Amount(output.Value)
					err = deleteRawUnspent(ns, outPointKey)
					if err != nil {
						return err
					}
				}
			}
		}

		err = it.delete()
		if err != nil {
			return err
		}
	}
	if it.err != nil {
		return it.err
	}

	for _, op := range coinBaseCredits {
		opKey := canonicalOutPoint(&op.Hash, op.Index)
		unminedKey := existsRawUnminedInput(ns, opKey)
		if unminedKey != nil {
			unminedVal := existsRawUnmined(ns, unminedKey)
			var unminedRec TxRecord
			copy(unminedRec.Hash[:], unminedKey) // Silly but need an array
			err = readRawTxRecord(&unminedRec.Hash, unminedVal, &unminedRec)
			if err != nil {
				return err
			}

			log.Debugf("Transaction %v spends a removed coinbase "+
				"output -- removing as well", unminedRec.Hash)
			err = s.removeConflict(ns, &unminedRec)
			if err != nil {
				return err
			}
		}
	}

	return putMinedBalance(ns, minedBalance)
}