1f6e63900d
* fix(core/txpool): fix typos * core/asm: fix typos * core/bloombits: fix typos * core/rawdb: fix typos
137 lines
3.6 KiB
Go
137 lines
3.6 KiB
Go
// Copyright 2017 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 asm provides support for dealing with EVM assembly instructions (e.g., disassembling them).
|
|
package asm
|
|
|
|
import (
|
|
"encoding/hex"
|
|
"fmt"
|
|
|
|
"github.com/ethereum/go-ethereum/core/vm"
|
|
)
|
|
|
|
// Iterator for disassembled EVM instructions
|
|
type instructionIterator struct {
|
|
code []byte
|
|
pc uint64
|
|
arg []byte
|
|
op vm.OpCode
|
|
error error
|
|
started bool
|
|
}
|
|
|
|
// NewInstructionIterator creates a new instruction iterator.
|
|
func NewInstructionIterator(code []byte) *instructionIterator {
|
|
it := new(instructionIterator)
|
|
it.code = code
|
|
return it
|
|
}
|
|
|
|
// Next returns true if there is a next instruction and moves on.
|
|
func (it *instructionIterator) Next() bool {
|
|
if it.error != nil || uint64(len(it.code)) <= it.pc {
|
|
// We previously reached an error or the end.
|
|
return false
|
|
}
|
|
|
|
if it.started {
|
|
// Since the iteration has been already started we move to the next instruction.
|
|
if it.arg != nil {
|
|
it.pc += uint64(len(it.arg))
|
|
}
|
|
it.pc++
|
|
} else {
|
|
// We start the iteration from the first instruction.
|
|
it.started = true
|
|
}
|
|
|
|
if uint64(len(it.code)) <= it.pc {
|
|
// We reached the end.
|
|
return false
|
|
}
|
|
|
|
it.op = vm.OpCode(it.code[it.pc])
|
|
if it.op.IsPush() {
|
|
a := uint64(it.op) - uint64(vm.PUSH1) + 1
|
|
u := it.pc + 1 + a
|
|
if uint64(len(it.code)) <= it.pc || uint64(len(it.code)) < u {
|
|
it.error = fmt.Errorf("incomplete push instruction at %v", it.pc)
|
|
return false
|
|
}
|
|
it.arg = it.code[it.pc+1 : u]
|
|
} else {
|
|
it.arg = nil
|
|
}
|
|
return true
|
|
}
|
|
|
|
// Error returns any error that may have been encountered.
|
|
func (it *instructionIterator) Error() error {
|
|
return it.error
|
|
}
|
|
|
|
// PC returns the PC of the current instruction.
|
|
func (it *instructionIterator) PC() uint64 {
|
|
return it.pc
|
|
}
|
|
|
|
// Op returns the opcode of the current instruction.
|
|
func (it *instructionIterator) Op() vm.OpCode {
|
|
return it.op
|
|
}
|
|
|
|
// Arg returns the argument of the current instruction.
|
|
func (it *instructionIterator) Arg() []byte {
|
|
return it.arg
|
|
}
|
|
|
|
// PrintDisassembled pretty-print all disassembled EVM instructions to stdout.
|
|
func PrintDisassembled(code string) error {
|
|
script, err := hex.DecodeString(code)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
it := NewInstructionIterator(script)
|
|
for it.Next() {
|
|
if it.Arg() != nil && 0 < len(it.Arg()) {
|
|
fmt.Printf("%05x: %v %#x\n", it.PC(), it.Op(), it.Arg())
|
|
} else {
|
|
fmt.Printf("%05x: %v\n", it.PC(), it.Op())
|
|
}
|
|
}
|
|
return it.Error()
|
|
}
|
|
|
|
// Disassemble returns all disassembled EVM instructions in human-readable format.
|
|
func Disassemble(script []byte) ([]string, error) {
|
|
instrs := make([]string, 0)
|
|
|
|
it := NewInstructionIterator(script)
|
|
for it.Next() {
|
|
if it.Arg() != nil && 0 < len(it.Arg()) {
|
|
instrs = append(instrs, fmt.Sprintf("%05x: %v %#x\n", it.PC(), it.Op(), it.Arg()))
|
|
} else {
|
|
instrs = append(instrs, fmt.Sprintf("%05x: %v\n", it.PC(), it.Op()))
|
|
}
|
|
}
|
|
if err := it.Error(); err != nil {
|
|
return nil, err
|
|
}
|
|
return instrs, nil
|
|
}
|