...

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)
+	}
+}