neo-go/pkg/core/state/tokens.go
2022-11-10 17:58:06 +03:00

228 lines
6.3 KiB
Go

package state
import (
"bytes"
"math/big"
"github.com/nspcc-dev/neo-go/pkg/config/limits"
"github.com/nspcc-dev/neo-go/pkg/encoding/bigint"
"github.com/nspcc-dev/neo-go/pkg/io"
"github.com/nspcc-dev/neo-go/pkg/util"
)
// TokenTransferBatchSize is the maximum number of entries for TokenTransferLog.
const TokenTransferBatchSize = 128
// TokenTransferLog is a serialized log of token transfers.
type TokenTransferLog struct {
Raw []byte
buf *bytes.Buffer
iow *io.BinWriter
}
// NEP17Transfer represents a single NEP-17 Transfer event.
type NEP17Transfer struct {
// Asset is a NEP-17 contract ID.
Asset int32
// Address is the address of the sender.
From util.Uint160
// To is the address of the receiver.
To util.Uint160
// Amount is the amount of tokens transferred.
// It is negative when tokens are sent and positive if they are received.
Amount big.Int
// Block is a number of block when the event occurred.
Block uint32
// Timestamp is the timestamp of the block where transfer occurred.
Timestamp uint64
// Tx is a hash the transaction.
Tx util.Uint256
}
// NEP11Transfer represents a single NEP-11 Transfer event.
type NEP11Transfer struct {
NEP17Transfer
// ID is a NEP-11 token ID.
ID []byte
}
// TokenTransferInfo stores a map of the contract IDs to the balance's last updated
// block trackers along with the information about NEP-17 and NEP-11 transfer batch.
type TokenTransferInfo struct {
LastUpdated map[int32]uint32
// NextNEP11Batch stores the index of the next NEP-11 transfer batch.
NextNEP11Batch uint32
// NextNEP17Batch stores the index of the next NEP-17 transfer batch.
NextNEP17Batch uint32
// NextNEP11NewestTimestamp stores the block timestamp of the first NEP-11 transfer in raw.
NextNEP11NewestTimestamp uint64
// NextNEP17NewestTimestamp stores the block timestamp of the first NEP-17 transfer in raw.
NextNEP17NewestTimestamp uint64
// NewNEP11Batch is true if batch with the `NextNEP11Batch` index should be created.
NewNEP11Batch bool
// NewNEP17Batch is true if batch with the `NextNEP17Batch` index should be created.
NewNEP17Batch bool
}
// NewTokenTransferInfo returns new TokenTransferInfo.
func NewTokenTransferInfo() *TokenTransferInfo {
return &TokenTransferInfo{
NewNEP11Batch: true,
NewNEP17Batch: true,
LastUpdated: make(map[int32]uint32),
}
}
// DecodeBinary implements the io.Serializable interface.
func (bs *TokenTransferInfo) DecodeBinary(r *io.BinReader) {
bs.NextNEP11Batch = r.ReadU32LE()
bs.NextNEP17Batch = r.ReadU32LE()
bs.NextNEP11NewestTimestamp = r.ReadU64LE()
bs.NextNEP17NewestTimestamp = r.ReadU64LE()
bs.NewNEP11Batch = r.ReadBool()
bs.NewNEP17Batch = r.ReadBool()
lenBalances := r.ReadVarUint()
m := make(map[int32]uint32, lenBalances)
for i := 0; i < int(lenBalances); i++ {
key := int32(r.ReadU32LE())
m[key] = r.ReadU32LE()
}
bs.LastUpdated = m
}
// EncodeBinary implements the io.Serializable interface.
func (bs *TokenTransferInfo) EncodeBinary(w *io.BinWriter) {
w.WriteU32LE(bs.NextNEP11Batch)
w.WriteU32LE(bs.NextNEP17Batch)
w.WriteU64LE(bs.NextNEP11NewestTimestamp)
w.WriteU64LE(bs.NextNEP17NewestTimestamp)
w.WriteBool(bs.NewNEP11Batch)
w.WriteBool(bs.NewNEP17Batch)
w.WriteVarUint(uint64(len(bs.LastUpdated)))
for k, v := range bs.LastUpdated {
w.WriteU32LE(uint32(k))
w.WriteU32LE(v)
}
}
// Append appends a single transfer to a log.
func (lg *TokenTransferLog) Append(tr io.Serializable) error {
// The first entry, set up counter.
if len(lg.Raw) == 0 {
lg.Raw = append(lg.Raw, 0)
}
if lg.buf == nil {
lg.buf = bytes.NewBuffer(lg.Raw)
}
if lg.iow == nil {
lg.iow = io.NewBinWriterFromIO(lg.buf)
}
tr.EncodeBinary(lg.iow)
if lg.iow.Err != nil {
return lg.iow.Err
}
lg.Raw = lg.buf.Bytes()
lg.Raw[0]++
return nil
}
// Reset resets the state of the log, clearing all entries, but keeping existing
// buffer for future writes.
func (lg *TokenTransferLog) Reset() {
lg.Raw = lg.Raw[:0]
lg.buf = nil
lg.iow = nil
}
// ForEachNEP11 iterates over a transfer log returning on the first error.
func (lg *TokenTransferLog) ForEachNEP11(f func(*NEP11Transfer) (bool, error)) (bool, error) {
if lg == nil || len(lg.Raw) == 0 {
return true, nil
}
transfers := make([]NEP11Transfer, lg.Size())
r := io.NewBinReaderFromBuf(lg.Raw[1:])
for i := 0; i < lg.Size(); i++ {
transfers[i].DecodeBinary(r)
}
if r.Err != nil {
return false, r.Err
}
for i := len(transfers) - 1; i >= 0; i-- {
cont, err := f(&transfers[i])
if err != nil || !cont {
return false, err
}
}
return true, nil
}
// ForEachNEP17 iterates over a transfer log returning on the first error.
func (lg *TokenTransferLog) ForEachNEP17(f func(*NEP17Transfer) (bool, error)) (bool, error) {
if lg == nil || len(lg.Raw) == 0 {
return true, nil
}
transfers := make([]NEP17Transfer, lg.Size())
r := io.NewBinReaderFromBuf(lg.Raw[1:])
for i := 0; i < lg.Size(); i++ {
transfers[i].DecodeBinary(r)
}
if r.Err != nil {
return false, r.Err
}
for i := len(transfers) - 1; i >= 0; i-- {
cont, err := f(&transfers[i])
if err != nil || !cont {
return false, err
}
}
return true, nil
}
// Size returns the amount of the transfer written in the log.
func (lg *TokenTransferLog) Size() int {
if len(lg.Raw) == 0 {
return 0
}
return int(lg.Raw[0])
}
// EncodeBinary implements the io.Serializable interface.
func (t *NEP17Transfer) EncodeBinary(w *io.BinWriter) {
var buf [bigint.MaxBytesLen]byte
w.WriteU32LE(uint32(t.Asset))
w.WriteBytes(t.Tx[:])
w.WriteBytes(t.From[:])
w.WriteBytes(t.To[:])
w.WriteU32LE(t.Block)
w.WriteU64LE(t.Timestamp)
amount := bigint.ToPreallocatedBytes(&t.Amount, buf[:])
w.WriteVarBytes(amount)
}
// DecodeBinary implements the io.Serializable interface.
func (t *NEP17Transfer) DecodeBinary(r *io.BinReader) {
t.Asset = int32(r.ReadU32LE())
r.ReadBytes(t.Tx[:])
r.ReadBytes(t.From[:])
r.ReadBytes(t.To[:])
t.Block = r.ReadU32LE()
t.Timestamp = r.ReadU64LE()
amount := r.ReadVarBytes(bigint.MaxBytesLen)
t.Amount = *bigint.FromBytes(amount)
}
// EncodeBinary implements the io.Serializable interface.
func (t *NEP11Transfer) EncodeBinary(w *io.BinWriter) {
t.NEP17Transfer.EncodeBinary(w)
w.WriteVarBytes(t.ID)
}
// DecodeBinary implements the io.Serializable interface.
func (t *NEP11Transfer) DecodeBinary(r *io.BinReader) {
t.NEP17Transfer.DecodeBinary(r)
t.ID = r.ReadVarBytes(limits.MaxStorageKeyLen)
}