neoneo-go/pkg/core/block/block.go
Roman Khimov 8bb1ecb45a network: remove priority queue from block queue
Use circular buffer which is a bit more appropriate. The problem is that
priority queue accepts and stores equal items which wastes memory even in
normal usage scenario, but it's especially dangerous if the node is stuck for
some reason. In this case it'll accept from peers and put into queue the same
blocks again and again leaking memory up to OOM condition.

Notice that queue length calculation might be wrong in case circular buffer
wraps, but it's not very likely to happen (usually blocks not coming from the
queue are added by consensus and it's not very fast in doing so).
2021-11-01 11:49:01 +03:00

224 lines
5.9 KiB
Go

package block
import (
"encoding/json"
"errors"
"math"
"github.com/nspcc-dev/neo-go/pkg/core/transaction"
"github.com/nspcc-dev/neo-go/pkg/crypto/hash"
"github.com/nspcc-dev/neo-go/pkg/io"
"github.com/nspcc-dev/neo-go/pkg/util"
)
const (
// MaxTransactionsPerBlock is the maximum number of transactions per block.
MaxTransactionsPerBlock = math.MaxUint16
)
// ErrMaxContentsPerBlock is returned when the maximum number of contents per block is reached.
var ErrMaxContentsPerBlock = errors.New("the number of contents exceeds the maximum number of contents per block")
var expectedHeaderSizeWithEmptyWitness int
func init() {
expectedHeaderSizeWithEmptyWitness = io.GetVarSize(new(Header))
}
// Block represents one block in the chain.
type Block struct {
// The base of the block.
Header
// Transaction list.
Transactions []*transaction.Transaction
// True if this block is created from trimmed data.
Trimmed bool
}
// auxBlockOut is used for JSON i/o.
type auxBlockOut struct {
Transactions []*transaction.Transaction `json:"tx"`
}
// auxBlockIn is used for JSON i/o.
type auxBlockIn struct {
Transactions []json.RawMessage `json:"tx"`
}
// ComputeMerkleRoot computes Merkle tree root hash based on actual block's data.
func (b *Block) ComputeMerkleRoot() util.Uint256 {
hashes := make([]util.Uint256, len(b.Transactions))
for i, tx := range b.Transactions {
hashes[i] = tx.Hash()
}
return hash.CalcMerkleRoot(hashes)
}
// RebuildMerkleRoot rebuilds the merkleroot of the block.
func (b *Block) RebuildMerkleRoot() {
b.MerkleRoot = b.ComputeMerkleRoot()
}
// NewBlockFromTrimmedBytes returns a new block from trimmed data.
// This is commonly used to create a block from stored data.
// Blocks created from trimmed data will have their Trimmed field
// set to true.
func NewBlockFromTrimmedBytes(stateRootEnabled bool, b []byte) (*Block, error) {
block := &Block{
Header: Header{
StateRootEnabled: stateRootEnabled,
},
Trimmed: true,
}
br := io.NewBinReaderFromBuf(b)
block.Header.DecodeBinary(br)
lenHashes := br.ReadVarUint()
if lenHashes > MaxTransactionsPerBlock {
return nil, ErrMaxContentsPerBlock
}
if lenHashes > 0 {
block.Transactions = make([]*transaction.Transaction, lenHashes)
for i := 0; i < int(lenHashes); i++ {
var hash util.Uint256
hash.DecodeBinary(br)
block.Transactions[i] = transaction.NewTrimmedTX(hash)
}
}
return block, br.Err
}
// New creates a new blank block with proper state root setting.
func New(stateRootEnabled bool) *Block {
return &Block{
Header: Header{
StateRootEnabled: stateRootEnabled,
},
}
}
// Trim returns a subset of the block data to save up space
// in storage.
// Notice that only the hashes of the transactions are stored.
func (b *Block) Trim() ([]byte, error) {
buf := io.NewBufBinWriter()
numTx := len(b.Transactions)
buf.Grow(b.GetExpectedBlockSizeWithoutTransactions(numTx) + util.Uint256Size*numTx)
b.Header.EncodeBinary(buf.BinWriter)
buf.WriteVarUint(uint64(numTx))
for _, tx := range b.Transactions {
h := tx.Hash()
h.EncodeBinary(buf.BinWriter)
}
if buf.Err != nil {
return nil, buf.Err
}
return buf.Bytes(), nil
}
// DecodeBinary decodes the block from the given BinReader, implementing
// Serializable interface.
func (b *Block) DecodeBinary(br *io.BinReader) {
b.Header.DecodeBinary(br)
contentsCount := br.ReadVarUint()
if contentsCount > MaxTransactionsPerBlock {
br.Err = ErrMaxContentsPerBlock
return
}
txes := make([]*transaction.Transaction, contentsCount)
for i := 0; i < int(contentsCount); i++ {
tx := &transaction.Transaction{}
tx.DecodeBinary(br)
txes[i] = tx
}
b.Transactions = txes
if br.Err != nil {
return
}
}
// EncodeBinary encodes the block to the given BinWriter, implementing
// Serializable interface.
func (b *Block) EncodeBinary(bw *io.BinWriter) {
b.Header.EncodeBinary(bw)
bw.WriteVarUint(uint64(len(b.Transactions)))
for i := 0; i < len(b.Transactions); i++ {
b.Transactions[i].EncodeBinary(bw)
}
}
// MarshalJSON implements json.Marshaler interface.
func (b Block) MarshalJSON() ([]byte, error) {
auxb, err := json.Marshal(auxBlockOut{
Transactions: b.Transactions,
})
if err != nil {
return nil, err
}
baseBytes, err := json.Marshal(b.Header)
if err != nil {
return nil, err
}
// Stitch them together.
if baseBytes[len(baseBytes)-1] != '}' || auxb[0] != '{' {
return nil, errors.New("can't merge internal jsons")
}
baseBytes[len(baseBytes)-1] = ','
baseBytes = append(baseBytes, auxb[1:]...)
return baseBytes, nil
}
// UnmarshalJSON implements json.Unmarshaler interface.
func (b *Block) UnmarshalJSON(data []byte) error {
// As Base and auxb are at the same level in json,
// do unmarshalling separately for both structs.
auxb := new(auxBlockIn)
err := json.Unmarshal(data, auxb)
if err != nil {
return err
}
err = json.Unmarshal(data, &b.Header)
if err != nil {
return err
}
if len(auxb.Transactions) != 0 {
b.Transactions = make([]*transaction.Transaction, 0, len(auxb.Transactions))
for _, txBytes := range auxb.Transactions {
tx := &transaction.Transaction{}
err = tx.UnmarshalJSON(txBytes)
if err != nil {
return err
}
b.Transactions = append(b.Transactions, tx)
}
}
return nil
}
// GetExpectedBlockSize returns expected block size which should be equal to io.GetVarSize(b).
func (b *Block) GetExpectedBlockSize() int {
var transactionsSize int
for _, tx := range b.Transactions {
transactionsSize += tx.Size()
}
return b.GetExpectedBlockSizeWithoutTransactions(len(b.Transactions)) + transactionsSize
}
// GetExpectedBlockSizeWithoutTransactions returns expected block size without transactions size.
func (b *Block) GetExpectedBlockSizeWithoutTransactions(txCount int) int {
size := expectedHeaderSizeWithEmptyWitness - 1 - 1 + // 1 is for the zero-length (new(Header)).Script.Invocation/Verification
io.GetVarSize(&b.Script) +
io.GetVarSize(txCount)
if b.StateRootEnabled {
size += util.Uint256Size
}
return size
}