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tx.go
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tx.go
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package wtxmgr
import (
"bytes"
"github.com/cybriq/p9/pkg/amt"
"github.com/cybriq/p9/pkg/chaincfg"
"time"
"github.com/cybriq/p9/pkg/blockchain"
"github.com/cybriq/p9/pkg/chainhash"
"github.com/cybriq/p9/pkg/walletdb"
"github.com/cybriq/p9/pkg/wire"
)
type (
// Block contains the minimum amount of data to uniquely identify any block on either the best or side chain.
Block struct {
Hash chainhash.Hash
Height int32
}
// BlockMeta contains the unique identification for a block and any metadata pertaining to the block. At the moment,
// this additional metadata only includes the block time from the block header.
BlockMeta struct {
Block
Time time.Time
}
// blockRecord is an in-memory representation of the block record saved in the database.
blockRecord struct {
Block
Time time.Time
transactions []chainhash.Hash
}
// incidence records the block hash and blockchain height of a mined transaction. Since a transaction hash alone is
// not enough to uniquely identify a mined transaction (duplicate transaction hashes are allowed), the incidence is
// used instead.
incidence struct {
txHash chainhash.Hash
block Block
}
// indexedIncidence records the transaction incidence and an input or output index.
indexedIncidence struct {
incidence
index uint32
}
// debit records the debits a transaction record makes from previous wallet transaction credits.
debit struct {
txHash chainhash.Hash
index uint32
amount amt.Amount
spends indexedIncidence
}
// credit describes a transaction output which was or is spendable by
// wallet.
credit struct {
outPoint wire.OutPoint
block Block
amount amt.Amount
change bool
spentBy indexedIncidence // Index == ^uint32(0) if unspent
}
// TxRecord represents a transaction managed by the Store.
TxRecord struct {
MsgTx wire.MsgTx
Hash chainhash.Hash
Received time.Time
SerializedTx []byte // Optional: may be nil
}
// Credit is the type representing a transaction output which was spent or is still spendable by wallet. A UTXO is
// an unspent Credit, but not all Credits are UTXOs.
Credit struct {
wire.OutPoint
BlockMeta
Amount amt.Amount
PkScript []byte
Received time.Time
FromCoinBase bool
}
// Store implements a transaction store for storing and managing wallet transactions.
Store struct {
chainParams *chaincfg.Params
// Event callbacks. These execute in the same goroutine as the wtxmgr caller.
NotifyUnspent func(hash *chainhash.Hash, index uint32)
}
)
// NewTxRecord creates a new transaction record that may be inserted into the store. It uses memoization to save the
// transaction hash and the serialized transaction.
func NewTxRecord(serializedTx []byte, received time.Time) (*TxRecord, error) {
rec := &TxRecord{
Received: received,
SerializedTx: serializedTx,
}
e := rec.MsgTx.Deserialize(bytes.NewReader(serializedTx))
if e != nil {
str := "failed to deserialize transaction"
return nil, storeError(ErrInput, str, e)
}
copy(rec.Hash[:], chainhash.DoubleHashB(serializedTx))
return rec, nil
}
// NewTxRecordFromMsgTx creates a new transaction record that may be inserted into the store.
func NewTxRecordFromMsgTx(msgTx *wire.MsgTx, received time.Time) (*TxRecord,
error,
) {
buf := bytes.NewBuffer(make([]byte, 0, msgTx.SerializeSize()))
e := msgTx.Serialize(buf)
if e != nil {
str := "failed to serialize transaction"
return nil, storeError(ErrInput, str, e)
}
rec := &TxRecord{
MsgTx: *msgTx,
Received: received,
SerializedTx: buf.Bytes(),
Hash: msgTx.TxHash(),
}
return rec, nil
}
// DoUpgrades performs any necessary upgrades to the transaction history contained in the wallet database, namespaced by
// the top level bucket key namespaceKey.
func DoUpgrades(db walletdb.DB, namespaceKey []byte) (e error) {
// No upgrades
return nil
}
// Open opens the wallet transaction store from a walletdb namespace.
// If the store does not exist, ErrNoExist is returned.
func Open(ns walletdb.ReadBucket, chainParams *chaincfg.Params) (*Store, error,
) {
// Open the store.
e := openStore(ns)
if e != nil {
return nil, e
}
s := &Store{chainParams, nil} // TODO: set callbacks
return s, nil
}
// Create creates a new persistent transaction store in the walletdb namespace. Creating the store when one already
// exists in this namespace will error with ErrAlreadyExists.
func Create(ns walletdb.ReadWriteBucket) (e error) {
return createStore(ns)
}
// updateMinedBalance updates the mined balance within the store, if changed, after processing the given transaction
// record.
func (s *Store) updateMinedBalance(
ns walletdb.ReadWriteBucket, rec *TxRecord,
block *BlockMeta,
) (e error) {
// Fetch the mined balance in case we need to update it.
minedBalance, e := fetchMinedBalance(ns)
if e != nil {
return e
}
// Add a debit record for each unspent credit spent by this transaction. The index is set in each iteration below.
spender := indexedIncidence{
incidence: incidence{
txHash: rec.Hash,
block: block.Block,
},
}
newMinedBalance := minedBalance
for i, input := range rec.MsgTx.TxIn {
unspentKey, credKey := existsUnspent(ns, &input.PreviousOutPoint)
if credKey == nil {
// Debits for unmined transactions are not explicitly tracked. Instead, all previous outputs spent by any
// unmined transaction are added to a map for quick lookups when it must be checked whether a mined output
// is unspent or not.
//
// Tracking individual debits for unmined transactions could be added later to simplify (and increase
// performance of) determining some details that need the previous outputs (e.g. determining a fee), but at
// the moment that is not done (and a db lookup is used for those cases instead).
//
// There is also a good chance that all unmined transaction handling will move entirely to the db rather
// than being handled in memory for atomicity reasons, so the simplist implementation is currently used.
continue
}
// If this output is relevant to us, we'll mark the it as spent and remove its amount from the store.
spender.index = uint32(i)
var amount amt.Amount
amount, e = spendCredit(ns, credKey, &spender)
if e != nil {
return e
}
e = putDebit(
ns, &rec.Hash, uint32(i), amount, &block.Block, credKey,
)
if e != nil {
return e
}
if e = deleteRawUnspent(ns, unspentKey); E.Chk(e) {
return e
}
newMinedBalance -= amount
}
// For each output of the record that is marked as a credit, if the output is marked as a credit by the unconfirmed
// store, remove the marker and mark the output as a credit in the db.
//
// Moved credits are added as unspents, even if there is another unconfirmed transaction which spends them.
cred := credit{
outPoint: wire.OutPoint{Hash: rec.Hash},
block: block.Block,
spentBy: indexedIncidence{index: ^uint32(0)},
}
it := makeUnminedCreditIterator(ns, &rec.Hash)
for it.next() {
// TODO: This should use the raw apis. The credit value (it.cv) can be moved from unmined directly to the
// credits bucket. The key needs a modification to include the block height/hash.
var index uint32
index, e = fetchRawUnminedCreditIndex(it.ck)
if e != nil {
return e
}
amount, change, e := fetchRawUnminedCreditAmountChange(it.cv)
if e != nil {
return e
}
cred.outPoint.Index = index
cred.amount = amount
cred.change = change
if e = putUnspentCredit(ns, &cred); E.Chk(e) {
return e
}
e = putUnspent(ns, &cred.outPoint, &block.Block)
if e != nil {
return e
}
newMinedBalance += amount
}
if it.err != nil {
return it.err
}
// Update the balance if it has changed.
if newMinedBalance != minedBalance {
return putMinedBalance(ns, newMinedBalance)
}
return nil
}
// deleteUnminedTx deletes an unmined transaction from the store.
//
// NOTE: This should only be used once the transaction has been mined.
func (s *Store) deleteUnminedTx(ns walletdb.ReadWriteBucket, rec *TxRecord,
) (e error) {
for i := range rec.MsgTx.TxOut {
k := canonicalOutPoint(&rec.Hash, uint32(i))
if e := deleteRawUnminedCredit(ns, k); E.Chk(e) {
return e
}
}
return deleteRawUnmined(ns, rec.Hash[:])
}
// InsertTx records a transaction as belonging to a wallet's transaction history. If block is nil, the transaction is
// considered unspent, and the transaction's index must be unset.
func (s *Store) InsertTx(ns walletdb.ReadWriteBucket, rec *TxRecord,
block *BlockMeta,
) (e error) {
if block == nil {
return s.insertMemPoolTx(ns, rec)
}
return s.insertMinedTx(ns, rec, block)
}
// RemoveUnminedTx attempts to remove an unmined transaction from the transaction store. This is to be used in the
// scenario that a transaction that we attempt to rebroadcast, turns out to double spend one of our existing inputs.
// This function we remove the conflicting transaction identified by the tx record, and also recursively remove all
// transactions that depend on it.
func (s *Store) RemoveUnminedTx(ns walletdb.ReadWriteBucket, rec *TxRecord,
) (e error) {
// As we already have a tx record, we can directly call the RemoveConflict method. This will do the job of
// recursively removing this unmined transaction, and any transactions that depend on it.
return RemoveConflict(ns, rec)
}
// insertMinedTx inserts a new transaction record for a mined transaction into the database under the confirmed bucket.
// It guarantees that, if the tranasction was previously unconfirmed, then it will take care of cleaning up the
// unconfirmed state. All other unconfirmed double spend attempts will be removed as well.
func (s *Store) insertMinedTx(
ns walletdb.ReadWriteBucket, rec *TxRecord,
block *BlockMeta,
) (e error) {
// If a transaction record for this hash and block already exists, we can exit early.
if _, v := existsTxRecord(ns, &rec.Hash, &block.Block); v != nil {
return nil
}
// If a block record does not yet exist for any transactions from this block, insert a block record first.
// Otherwise, update it by adding the transaction hash to the set of transactions from this block.
blockKey, blockValue := existsBlockRecord(ns, block.Height)
if blockValue == nil {
e = putBlockRecord(ns, block, &rec.Hash)
} else {
blockValue, e = appendRawBlockRecord(blockValue, &rec.Hash)
if e != nil {
return e
}
e = putRawBlockRecord(ns, blockKey, blockValue)
}
if e != nil {
return e
}
if e := putTxRecord(ns, rec, &block.Block); E.Chk(e) {
return e
}
// Determine if this transaction has affected our balance, and if so, update it.
if e := s.updateMinedBalance(ns, rec, block); E.Chk(e) {
return e
}
// If this transaction previously existed within the store as unmined, we'll need to remove it from the unmined
// bucket.
if v := existsRawUnmined(ns, rec.Hash[:]); v != nil {
I.F("marking unconfirmed transaction %v mined in block %d", &rec.Hash,
block.Height,
)
if e := s.deleteUnminedTx(ns, rec); E.Chk(e) {
return e
}
}
// As there may be unconfirmed transactions that are invalidated by this transaction (either being duplicates, or
// double spends), remove them from the unconfirmed set. This also handles removing unconfirmed transaction spend
// chains if any other unconfirmed transactions spend outputs of the removed double spend.
return s.removeDoubleSpends(ns, rec)
}
// AddCredit marks a transaction record as containing a transaction output spendable by wallet. The output is added
// unspent, and is marked spent when a new transaction spending the output is inserted into the store.
//
// TODO(jrick): This should not be necessary. Instead, pass the indexes that are known to contain credits when a
// transaction or merkleblock is inserted into the store.
func (s *Store) AddCredit(
ns walletdb.ReadWriteBucket,
rec *TxRecord,
block *BlockMeta,
index uint32,
change bool,
) (e error) {
if int(index) >= len(rec.MsgTx.TxOut) {
str := "transaction output does not exist"
return storeError(ErrInput, str, nil)
}
isNew, e := s.addCredit(ns, rec, block, index, change)
if e == nil && isNew && s.NotifyUnspent != nil {
s.NotifyUnspent(&rec.Hash, index)
}
return e
}
// addCredit is an AddCredit helper that runs in an update transaction. The bool return specifies whether the unspent
// output is newly added ( true) or a duplicate (false).
func (s *Store) addCredit(
ns walletdb.ReadWriteBucket,
rec *TxRecord,
block *BlockMeta,
index uint32,
change bool,
) (bool, error) {
if block == nil {
// If the outpoint that we should mark as credit already exists within the store, either as unconfirmed or
// confirmed, then we have nothing left to do and can exit.
k := canonicalOutPoint(&rec.Hash, index)
if existsRawUnminedCredit(ns, k) != nil {
return false, nil
}
if existsRawUnspent(ns, k) != nil {
return false, nil
}
v := valueUnminedCredit(amt.Amount(rec.MsgTx.TxOut[index].Value),
change,
)
return true, putRawUnminedCredit(ns, k, v)
}
k, v := existsCredit(ns, &rec.Hash, index, &block.Block)
if v != nil {
return false, nil
}
txOutAmt := amt.Amount(rec.MsgTx.TxOut[index].Value)
T.F(
"marking transaction %v output %d (%v) spendable",
rec.Hash, index, txOutAmt,
)
cred := credit{
outPoint: wire.OutPoint{
Hash: rec.Hash,
Index: index,
},
block: block.Block,
amount: txOutAmt,
change: change,
spentBy: indexedIncidence{index: ^uint32(0)},
}
v = valueUnspentCredit(&cred)
e := putRawCredit(ns, k, v)
if e != nil {
return false, e
}
minedBalance, e := fetchMinedBalance(ns)
if e != nil {
return false, e
}
e = putMinedBalance(ns, minedBalance+txOutAmt)
if e != nil {
return false, e
}
return true, putUnspent(ns, &cred.outPoint, &block.Block)
}
// Rollback removes all blocks at height onwards, moving any transactions within each block to the unconfirmed pool.
func (s *Store) Rollback(ns walletdb.ReadWriteBucket, height int32) (e error) {
return s.rollback(ns, height)
}
func (s *Store) rollback(ns walletdb.ReadWriteBucket, height int32) (e error) {
minedBalance, e := fetchMinedBalance(ns)
if e != nil {
return e
}
// 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
var heightsToRemove []int32
it := makeReverseBlockIterator(ns)
for it.prev() {
b := &it.elem
if it.elem.Height < height {
break
}
heightsToRemove = append(heightsToRemove, it.elem.Height)
T.F("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
e = readRawTxRecord(txHash, recVal, &rec)
if e != nil {
return e
}
e = deleteTxRecord(ns, txHash, &b.Block)
if e != nil {
return e
}
// 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 -= amt.Amount(output.Value)
e = deleteRawUnspent(ns, unspentKey)
if e != nil {
return e
}
}
e = deleteRawCredit(ns, k)
if e != nil {
return e
}
}
continue
}
e = putRawUnmined(ns, txHash[:], recVal)
if e != nil {
return e
}
// 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,
)
e = putRawUnminedInput(ns, prevOutKey, rec.Hash[:])
if e != nil {
return e
}
// If this input is a debit, remove the debit record and mark the credit that it spent as unspent,
// incrementing the mined balance.
var debKey, credKey []byte
debKey, credKey, e = existsDebit(
ns,
&rec.Hash, uint32(i), &b.Block,
)
if e != nil {
return e
}
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 amount amt.Amount
amount, e = unspendRawCredit(ns, credKey)
if e != nil {
return e
}
e = deleteRawDebit(ns, debKey)
if e != nil {
return e
}
// 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 amount == 0 {
continue
}
var unspentVal []byte
unspentVal, e = fetchRawCreditUnspentValue(credKey)
if e != nil {
return e
}
minedBalance += amount
e = putRawUnspent(ns, prevOutKey, unspentVal)
if e != nil {
return e
}
}
// 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
}
var amountChange amt.Amount
change := false
amountChange, change, e = fetchRawCreditAmountChange(v)
if e != nil {
return e
}
outPointKey := canonicalOutPoint(&rec.Hash, uint32(i))
unminedCredVal := valueUnminedCredit(amountChange, change)
e = putRawUnminedCredit(ns, outPointKey, unminedCredVal)
if e != nil {
return e
}
e = deleteRawCredit(ns, k)
if e != nil {
return e
}
credKey := existsRawUnspent(ns, outPointKey)
if credKey != nil {
minedBalance -= amt.Amount(output.Value)
e = deleteRawUnspent(ns, outPointKey)
if e != nil {
return e
}
}
}
}
// reposition cursor before deleting this k/v pair and advancing to the previous.
it.reposition(it.elem.Height)
// Avoid cursor deletion until bolt issue #620 is resolved.
//
// e = it.delete() if e != nil {
// return e
// }
}
if it.err != nil {
return it.err
}
// Delete the block records outside of the iteration since cursor deletion is broken.
for _, h := range heightsToRemove {
e = deleteBlockRecord(ns, h)
if e != nil {
return e
}
}
for _, op := range coinBaseCredits {
opKey := canonicalOutPoint(&op.Hash, op.Index)
unminedSpendTxHashKeys := fetchUnminedInputSpendTxHashes(ns, opKey)
for _, unminedSpendTxHashKey := range unminedSpendTxHashKeys {
unminedVal := existsRawUnmined(ns, unminedSpendTxHashKey[:])
// If the spending transaction spends multiple outputs
// from the same transaction, we'll find duplicate
// entries within the store, so it's possible we're
// unable to find it if the conflicts have already been
// removed in a previous iteration.
if unminedVal == nil {
continue
}
var unminedRec TxRecord
unminedRec.Hash = unminedSpendTxHashKey
e = readRawTxRecord(&unminedRec.Hash, unminedVal, &unminedRec)
if e != nil {
return e
}
D.F(
"transaction %v spends a removed coinbase output -- removing as well %s",
unminedRec.Hash,
)
e = RemoveConflict(ns, &unminedRec)
if e != nil {
return e
}
}
}
return putMinedBalance(ns, minedBalance)
}
func // UnspentOutputs returns all unspent received transaction outputs.
// The order is undefined.
(s *Store) UnspentOutputs(ns walletdb.ReadBucket) ([]Credit, error) {
var unspent []Credit
var op wire.OutPoint
var block Block
e := ns.NestedReadBucket(bucketUnspent).ForEach(
func(k, v []byte) (e error) {
e = readCanonicalOutPoint(k, &op)
if e != nil {
return e
}
if existsRawUnminedInput(ns, k) != nil {
// Output is spent by an unmined transaction.
// Skip this k/v pair.
return nil
}
e = readUnspentBlock(v, &block)
if e != nil {
return e
}
blockTime, e := fetchBlockTime(ns, block.Height)
if e != nil {
return e
}
// TODO(jrick): reading the entire transaction should
// be avoidable. Creating the credit only requires the
// output amount and pkScript.
rec, e := fetchTxRecord(ns, &op.Hash, &block)
if e != nil {
return e
}
txOut := rec.MsgTx.TxOut[op.Index]
cred := Credit{
OutPoint: op,
BlockMeta: BlockMeta{
Block: block,
Time: blockTime,
},
Amount: amt.Amount(txOut.Value),
PkScript: txOut.PkScript,
Received: rec.Received,
FromCoinBase: blockchain.IsCoinBaseTx(&rec.MsgTx),
}
unspent = append(unspent, cred)
return nil
},
)
if e != nil {
if _, ok := e.(TxMgrError); ok {
return nil, e
}
str := "failed iterating unspent bucket"
return nil, storeError(ErrDatabase, str, e)
}
e = ns.NestedReadBucket(bucketUnminedCredits).ForEach(
func(k, v []byte) (e error) {
if existsRawUnminedInput(ns, k) != nil {
// Output is spent by an unmined transaction.
// Skip to next unmined credit.
return nil
}
e = readCanonicalOutPoint(k, &op)
if e != nil {
return e
}
// 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
e = readRawTxRecord(&op.Hash, recVal, &rec)
if e != nil {
return e
}
txOut := rec.MsgTx.TxOut[op.Index]
cred := Credit{
OutPoint: op,
BlockMeta: BlockMeta{
Block: Block{Height: -1},
},
Amount: amt.Amount(txOut.Value),
PkScript: txOut.PkScript,
Received: rec.Received,
FromCoinBase: blockchain.IsCoinBaseTx(&rec.MsgTx),
}
unspent = append(unspent, cred)
return nil
},
)
if e != nil {
if _, ok := e.(TxMgrError); ok {
return nil, e
}
str := "failed iterating unmined credits bucket"
return nil, storeError(ErrDatabase, str, e)
}
return unspent, nil
}
func // Balance returns the spendable wallet balance (total value of all unspent
// transaction outputs) given a minimum of minConf confirmations, calculated
// at a current chain height of curHeight. Coinbase outputs are only included
// in the balance if maturity has been reached.
//
// Balance may return unexpected results if syncHeight is lower than the block
// height of the most recent mined transaction in the store.
(s *Store) Balance(ns walletdb.ReadBucket, minConf int32, syncHeight int32,
) (amt.Amount, error) {
bal, e := fetchMinedBalance(ns)
if e != nil {
return 0, e
}
// Subtract the balance for each credit that is spent by an unmined
// transaction.
var op wire.OutPoint
var block Block
e = ns.NestedReadBucket(bucketUnspent).ForEach(
func(k, v []byte) (e error) {
e = readCanonicalOutPoint(k, &op)
if e != nil {
return e
}
e = readUnspentBlock(v, &block)
if e != nil {
return e
}
if existsRawUnminedInput(ns, k) != nil {
_, v := existsCredit(ns, &op.Hash, op.Index, &block)
var amount amt.Amount
amount, e = fetchRawCreditAmount(v)
if e != nil {
return e
}
bal -= amount
}
return nil
},
)
if e != nil {
if _, ok := e.(TxMgrError); ok {
return 0, e
}
str := "failed iterating unspent outputs"
return 0, storeError(ErrDatabase, str, e)
}
// Decrement the balance for any unspent credit with less than
// minConf confirmations and any (unspent) immature coinbase credit.
coinbaseMaturity := int32(s.chainParams.CoinbaseMaturity)
stopConf := minConf
if coinbaseMaturity > stopConf {
stopConf = coinbaseMaturity
}
lastHeight := syncHeight - stopConf
blockIt := makeReadReverseBlockIterator(ns)
for blockIt.prev() {
block := &blockIt.elem
if block.Height < lastHeight {
break
}
for i := range block.transactions {
txHash := &block.transactions[i]
var rec *TxRecord
rec, e = fetchTxRecord(ns, txHash, &block.Block)
if e != nil {
return 0, e
}
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
}
var amountSpent amt.Amount
var spent bool
amountSpent, spent, e = fetchRawCreditAmountSpent(v)
if e != nil {
return 0, e
}
if spent {
continue
}
confs := syncHeight - block.Height + 1
if confs < minConf || (blockchain.IsCoinBaseTx(&rec.MsgTx) &&
confs < coinbaseMaturity) {
bal -= amountSpent
}
}
}
}
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 {
e = ns.NestedReadBucket(bucketUnminedCredits).ForEach(
func(k, v []byte) (e error) {
if existsRawUnminedInput(ns, k) != nil {
// Output is spent by an unmined transaction.
// Skip to next unmined credit.
return nil
}
amount, e := fetchRawUnminedCreditAmount(v)
if e != nil {
return e
}
bal += amount
return nil
},
)
if e != nil {
if _, ok := e.(TxMgrError); ok {
return 0, e
}
str := "failed to iterate over unmined credits bucket"
return 0, storeError(ErrDatabase, str, e)
}
}
return bal, nil
}