go-ethereum/core/vm/log.go

135 lines
4.5 KiB
Go

// Copyright 2014 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
package vm
import (
"encoding/json"
"errors"
"fmt"
"io"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/rlp"
)
var errMissingLogFields = errors.New("missing required JSON log fields")
// Log represents a contract log event. These events are generated by the LOG
// opcode and stored/indexed by the node.
type Log struct {
// Consensus fields.
Address common.Address // address of the contract that generated the event
Topics []common.Hash // list of topics provided by the contract.
Data []byte // supplied by the contract, usually ABI-encoded
// Derived fields (don't reorder!).
BlockNumber uint64 // block in which the transaction was included
TxHash common.Hash // hash of the transaction
TxIndex uint // index of the transaction in the block
BlockHash common.Hash // hash of the block in which the transaction was included
Index uint // index of the log in the receipt
}
type jsonLog struct {
Address *common.Address `json:"address"`
Topics *[]common.Hash `json:"topics"`
Data string `json:"data"`
BlockNumber string `json:"blockNumber"`
TxIndex string `json:"transactionIndex"`
TxHash *common.Hash `json:"transactionHash"`
BlockHash *common.Hash `json:"blockHash"`
Index string `json:"logIndex"`
}
func NewLog(address common.Address, topics []common.Hash, data []byte, number uint64) *Log {
return &Log{Address: address, Topics: topics, Data: data, BlockNumber: number}
}
func (l *Log) EncodeRLP(w io.Writer) error {
return rlp.Encode(w, []interface{}{l.Address, l.Topics, l.Data})
}
func (l *Log) DecodeRLP(s *rlp.Stream) error {
var log struct {
Address common.Address
Topics []common.Hash
Data []byte
}
if err := s.Decode(&log); err != nil {
return err
}
l.Address, l.Topics, l.Data = log.Address, log.Topics, log.Data
return nil
}
func (l *Log) String() string {
return fmt.Sprintf(`log: %x %x %x %x %d %x %d`, l.Address, l.Topics, l.Data, l.TxHash, l.TxIndex, l.BlockHash, l.Index)
}
// MarshalJSON implements json.Marshaler.
func (r *Log) MarshalJSON() ([]byte, error) {
return json.Marshal(&jsonLog{
Address: &r.Address,
Topics: &r.Topics,
Data: fmt.Sprintf("0x%x", r.Data),
BlockNumber: fmt.Sprintf("0x%x", r.BlockNumber),
TxIndex: fmt.Sprintf("0x%x", r.TxIndex),
TxHash: &r.TxHash,
BlockHash: &r.BlockHash,
Index: fmt.Sprintf("0x%x", r.Index),
})
}
// UnmarshalJSON implements json.Umarshaler.
func (r *Log) UnmarshalJSON(input []byte) error {
var dec jsonLog
if err := json.Unmarshal(input, &dec); err != nil {
return err
}
if dec.Address == nil || dec.Topics == nil || dec.Data == "" || dec.BlockNumber == "" ||
dec.TxIndex == "" || dec.TxHash == nil || dec.BlockHash == nil || dec.Index == "" {
return errMissingLogFields
}
declog := Log{
Address: *dec.Address,
Topics: *dec.Topics,
TxHash: *dec.TxHash,
BlockHash: *dec.BlockHash,
}
if _, err := fmt.Sscanf(dec.Data, "0x%x", &declog.Data); err != nil {
return fmt.Errorf("invalid hex log data")
}
if _, err := fmt.Sscanf(dec.BlockNumber, "0x%x", &declog.BlockNumber); err != nil {
return fmt.Errorf("invalid hex log block number")
}
if _, err := fmt.Sscanf(dec.TxIndex, "0x%x", &declog.TxIndex); err != nil {
return fmt.Errorf("invalid hex log tx index")
}
if _, err := fmt.Sscanf(dec.Index, "0x%x", &declog.Index); err != nil {
return fmt.Errorf("invalid hex log index")
}
*r = declog
return nil
}
type Logs []*Log
// LogForStorage is a wrapper around a Log that flattens and parses the entire
// content of a log, as opposed to only the consensus fields originally (by hiding
// the rlp interface methods).
type LogForStorage Log