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Diffstat (limited to 'core/vm/logger.go')
| -rw-r--r-- | core/vm/logger.go | 256 |
1 files changed, 256 insertions, 0 deletions
diff --git a/core/vm/logger.go b/core/vm/logger.go new file mode 100644 index 0000000..95143f1 --- /dev/null +++ b/core/vm/logger.go @@ -0,0 +1,256 @@ +// Copyright 2015 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/hex" + "fmt" + "io" + "math/big" + "time" + + "github.com/ava-labs/coreth/core/types" + "github.com/ava-labs/go-ethereum/common" + "github.com/ava-labs/go-ethereum/common/hexutil" + "github.com/ava-labs/go-ethereum/common/math" +) + +// Storage represents a contract's storage. +type Storage map[common.Hash]common.Hash + +// Copy duplicates the current storage. +func (s Storage) Copy() Storage { + cpy := make(Storage) + for key, value := range s { + cpy[key] = value + } + + return cpy +} + +// LogConfig are the configuration options for structured logger the EVM +type LogConfig struct { + DisableMemory bool // disable memory capture + DisableStack bool // disable stack capture + DisableStorage bool // disable storage capture + Debug bool // print output during capture end + Limit int // maximum length of output, but zero means unlimited +} + +//go:generate gencodec -type StructLog -field-override structLogMarshaling -out gen_structlog.go + +// StructLog is emitted to the EVM each cycle and lists information about the current internal state +// prior to the execution of the statement. +type StructLog struct { + Pc uint64 `json:"pc"` + Op OpCode `json:"op"` + Gas uint64 `json:"gas"` + GasCost uint64 `json:"gasCost"` + Memory []byte `json:"memory"` + MemorySize int `json:"memSize"` + Stack []*big.Int `json:"stack"` + Storage map[common.Hash]common.Hash `json:"-"` + Depth int `json:"depth"` + RefundCounter uint64 `json:"refund"` + Err error `json:"-"` +} + +// overrides for gencodec +type structLogMarshaling struct { + Stack []*math.HexOrDecimal256 + Gas math.HexOrDecimal64 + GasCost math.HexOrDecimal64 + Memory hexutil.Bytes + OpName string `json:"opName"` // adds call to OpName() in MarshalJSON + ErrorString string `json:"error"` // adds call to ErrorString() in MarshalJSON +} + +// OpName formats the operand name in a human-readable format. +func (s *StructLog) OpName() string { + return s.Op.String() +} + +// ErrorString formats the log's error as a string. +func (s *StructLog) ErrorString() string { + if s.Err != nil { + return s.Err.Error() + } + return "" +} + +// Tracer is used to collect execution traces from an EVM transaction +// execution. CaptureState is called for each step of the VM with the +// current VM state. +// Note that reference types are actual VM data structures; make copies +// if you need to retain them beyond the current call. +type Tracer interface { + CaptureStart(from common.Address, to common.Address, call bool, input []byte, gas uint64, value *big.Int) error + CaptureState(env *EVM, pc uint64, op OpCode, gas, cost uint64, memory *Memory, stack *Stack, contract *Contract, depth int, err error) error + CaptureFault(env *EVM, pc uint64, op OpCode, gas, cost uint64, memory *Memory, stack *Stack, contract *Contract, depth int, err error) error + CaptureEnd(output []byte, gasUsed uint64, t time.Duration, err error) error +} + +// StructLogger is an EVM state logger and implements Tracer. +// +// StructLogger can capture state based on the given Log configuration and also keeps +// a track record of modified storage which is used in reporting snapshots of the +// contract their storage. +type StructLogger struct { + cfg LogConfig + + logs []StructLog + changedValues map[common.Address]Storage + output []byte + err error +} + +// NewStructLogger returns a new logger +func NewStructLogger(cfg *LogConfig) *StructLogger { + logger := &StructLogger{ + changedValues: make(map[common.Address]Storage), + } + if cfg != nil { + logger.cfg = *cfg + } + return logger +} + +// CaptureStart implements the Tracer interface to initialize the tracing operation. +func (l *StructLogger) CaptureStart(from common.Address, to common.Address, create bool, input []byte, gas uint64, value *big.Int) error { + return nil +} + +// CaptureState logs a new structured log message and pushes it out to the environment +// +// CaptureState also tracks SSTORE ops to track dirty values. +func (l *StructLogger) CaptureState(env *EVM, pc uint64, op OpCode, gas, cost uint64, memory *Memory, stack *Stack, contract *Contract, depth int, err error) error { + // check if already accumulated the specified number of logs + if l.cfg.Limit != 0 && l.cfg.Limit <= len(l.logs) { + return ErrTraceLimitReached + } + + // initialise new changed values storage container for this contract + // if not present. + if l.changedValues[contract.Address()] == nil { + l.changedValues[contract.Address()] = make(Storage) + } + + // capture SSTORE opcodes and determine the changed value and store + // it in the local storage container. + if op == SSTORE && stack.len() >= 2 { + var ( + value = common.BigToHash(stack.data[stack.len()-2]) + address = common.BigToHash(stack.data[stack.len()-1]) + ) + l.changedValues[contract.Address()][address] = value + } + // Copy a snapshot of the current memory state to a new buffer + var mem []byte + if !l.cfg.DisableMemory { + mem = make([]byte, len(memory.Data())) + copy(mem, memory.Data()) + } + // Copy a snapshot of the current stack state to a new buffer + var stck []*big.Int + if !l.cfg.DisableStack { + stck = make([]*big.Int, len(stack.Data())) + for i, item := range stack.Data() { + stck[i] = new(big.Int).Set(item) + } + } + // Copy a snapshot of the current storage to a new container + var storage Storage + if !l.cfg.DisableStorage { + storage = l.changedValues[contract.Address()].Copy() + } + // create a new snapshot of the EVM. + log := StructLog{pc, op, gas, cost, mem, memory.Len(), stck, storage, depth, env.StateDB.GetRefund(), err} + + l.logs = append(l.logs, log) + return nil +} + +// CaptureFault implements the Tracer interface to trace an execution fault +// while running an opcode. +func (l *StructLogger) CaptureFault(env *EVM, pc uint64, op OpCode, gas, cost uint64, memory *Memory, stack *Stack, contract *Contract, depth int, err error) error { + return nil +} + +// CaptureEnd is called after the call finishes to finalize the tracing. +func (l *StructLogger) CaptureEnd(output []byte, gasUsed uint64, t time.Duration, err error) error { + l.output = output + l.err = err + if l.cfg.Debug { + fmt.Printf("0x%x\n", output) + if err != nil { + fmt.Printf(" error: %v\n", err) + } + } + return nil +} + +// StructLogs returns the captured log entries. +func (l *StructLogger) StructLogs() []StructLog { return l.logs } + +// Error returns the VM error captured by the trace. +func (l *StructLogger) Error() error { return l.err } + +// Output returns the VM return value captured by the trace. +func (l *StructLogger) Output() []byte { return l.output } + +// WriteTrace writes a formatted trace to the given writer +func WriteTrace(writer io.Writer, logs []StructLog) { + for _, log := range logs { + fmt.Fprintf(writer, "%-16spc=%08d gas=%v cost=%v", log.Op, log.Pc, log.Gas, log.GasCost) + if log.Err != nil { + fmt.Fprintf(writer, " ERROR: %v", log.Err) + } + fmt.Fprintln(writer) + + if len(log.Stack) > 0 { + fmt.Fprintln(writer, "Stack:") + for i := len(log.Stack) - 1; i >= 0; i-- { + fmt.Fprintf(writer, "%08d %x\n", len(log.Stack)-i-1, math.PaddedBigBytes(log.Stack[i], 32)) + } + } + if len(log.Memory) > 0 { + fmt.Fprintln(writer, "Memory:") + fmt.Fprint(writer, hex.Dump(log.Memory)) + } + if len(log.Storage) > 0 { + fmt.Fprintln(writer, "Storage:") + for h, item := range log.Storage { + fmt.Fprintf(writer, "%x: %x\n", h, item) + } + } + fmt.Fprintln(writer) + } +} + +// WriteLogs writes vm logs in a readable format to the given writer +func WriteLogs(writer io.Writer, logs []*types.Log) { + for _, log := range logs { + fmt.Fprintf(writer, "LOG%d: %x bn=%d txi=%x\n", len(log.Topics), log.Address, log.BlockNumber, log.TxIndex) + + for i, topic := range log.Topics { + fmt.Fprintf(writer, "%08d %x\n", i, topic) + } + + fmt.Fprint(writer, hex.Dump(log.Data)) + fmt.Fprintln(writer) + } +} |