// 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)
}
}
// 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()
}
}
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
}
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
}
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)
}
