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blockchain/cfindex: Factor out filter/header calc.

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Alex 2017-04-26 18:55:24 -06:00 committed by Olaoluwa Osuntokun
parent f11e87c957
commit 1c5f25bbf2
1 changed files with 12 additions and 68 deletions
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80
blockchain/indexers/cfindex.go
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@ -12,6 +12,7 @@ import (
"github.com/btcsuite/btcd/chaincfg/chainhash"
"github.com/btcsuite/btcd/database"
"github.com/btcsuite/btcutil"
"github.com/btcsuite/btcutil/gcs"
"github.com/btcsuite/btcutil/gcs/builder"
"github.com/btcsuite/fastsha256"
)
@ -158,71 +159,10 @@ func (idx *CfIndex) Create(dbTx database.Tx) error {
return err
}
// makeBasicFilterForBlock builds a block's basic filter, which consists of
// all outpoints and pkscript data pushes referenced by transactions within the
// block.
func makeBasicFilterForBlock(block *btcutil.Block) ([]byte, error) {
b := builder.WithKeyHash(block.Hash())
_, err := b.Key()
if err != nil {
return nil, err
}
for i, tx := range block.Transactions() {
// Skip the inputs for the coinbase transaction
if i != 0 {
for _, txIn := range tx.MsgTx().TxIn {
b.AddOutPoint(txIn.PreviousOutPoint)
}
}
for _, txOut := range tx.MsgTx().TxOut {
b.AddScript(txOut.PkScript)
}
}
f, err := b.Build()
if err != nil {
return nil, err
}
return f.NBytes(), nil
}
// makeExtendedFilterForBlock builds a block's extended filter, which consists
// of all tx hashes and sigscript data pushes contained in the block.
func makeExtendedFilterForBlock(block *btcutil.Block) ([]byte, error) {
b := builder.WithKeyHash(block.Hash())
_, err := b.Key()
if err != nil {
return nil, err
}
for i, tx := range block.Transactions() {
b.AddHash(tx.Hash())
// Skip the inputs for the coinbase transaction
if i != 0 {
for _, txIn := range tx.MsgTx().TxIn {
b.AddScript(txIn.SignatureScript)
}
}
}
f, err := b.Build()
if err != nil {
return nil, err
}
return f.NBytes(), nil
}
// makeHeaderForFilter implements the chaining logic between filters, where
// a filter's header is defined as sha256(sha256(filter) + previousFilterHeader).
func makeHeaderForFilter(f, pfh []byte) []byte {
fhash := fastsha256.Sum256(f)
chain := make([]byte, 0, 2*fastsha256.Size)
chain = append(chain, fhash[:]...)
chain = append(chain, pfh...)
fh := fastsha256.Sum256(chain)
return fh[:]
}
// storeFilter stores a given filter, and performs the steps needed to
// generate the filter's header.
func storeFilter(dbTx database.Tx, block *btcutil.Block, f []byte, extended bool) error {
func storeFilter(dbTx database.Tx, block *btcutil.Block, f *gcs.Filter,
extended bool) error {
// Figure out which buckets to use.
fkey := cfBasicIndexKey
hkey := cfBasicHeaderKey
@ -232,7 +172,7 @@ func storeFilter(dbTx database.Tx, block *btcutil.Block, f []byte, extended bool
}
// Start by storing the filter.
h := block.Hash()
err := dbStoreFilter(dbTx, fkey, h, f)
err := dbStoreFilter(dbTx, fkey, h, f.NBytes())
if err != nil {
return err
}
@ -243,8 +183,12 @@ func storeFilter(dbTx database.Tx, block *btcutil.Block, f []byte, extended bool
return err
}
// Construct the new block's filter header, and store it.
fh := makeHeaderForFilter(f, pfh)
return dbStoreFilterHeader(dbTx, hkey, h, fh)
prevHeader, err := chainhash.NewHash(pfh)
if err != nil {
return err
}
fh := builder.MakeHeaderForFilter(f, *prevHeader)
return dbStoreFilterHeader(dbTx, hkey, h, fh[:])
}
// ConnectBlock is invoked by the index manager when a new block has been
@ -252,7 +196,7 @@ func storeFilter(dbTx database.Tx, block *btcutil.Block, f []byte, extended bool
// every passed block. This is part of the Indexer interface.
func (idx *CfIndex) ConnectBlock(dbTx database.Tx, block *btcutil.Block,
view *blockchain.UtxoViewpoint) error {
f, err := makeBasicFilterForBlock(block)
f, err := builder.BuildBasicFilter(block.MsgBlock())
if err != nil {
return err
}
@ -260,7 +204,7 @@ func (idx *CfIndex) ConnectBlock(dbTx database.Tx, block *btcutil.Block,
if err != nil {
return err
}
f, err = makeExtendedFilterForBlock(block)
f, err = builder.BuildExtFilter(block.MsgBlock())
if err != nil {
return err
}