go-ethereum/core/vm/asm.go
Felix Lange 3f047be5aa all: update license headers to distiguish GPL/LGPL
All code outside of cmd/ is licensed as LGPL. The headers
now reflect this by calling the whole work "the go-ethereum library".
2015-07-22 18:51:45 +02:00

62 lines
1.8 KiB
Go

// Copyright 2014 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// go-ethereum 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 (
"fmt"
"math/big"
"github.com/ethereum/go-ethereum/common"
)
func Disassemble(script []byte) (asm []string) {
pc := new(big.Int)
for {
if pc.Cmp(big.NewInt(int64(len(script)))) >= 0 {
return
}
// Get the memory location of pc
val := script[pc.Int64()]
// Get the opcode (it must be an opcode!)
op := OpCode(val)
asm = append(asm, fmt.Sprintf("%v", op))
switch op {
case PUSH1, PUSH2, PUSH3, PUSH4, PUSH5, PUSH6, PUSH7, PUSH8, PUSH9, PUSH10, PUSH11, PUSH12, PUSH13, PUSH14, PUSH15, PUSH16, PUSH17, PUSH18, PUSH19, PUSH20, PUSH21, PUSH22, PUSH23, PUSH24, PUSH25, PUSH26, PUSH27, PUSH28, PUSH29, PUSH30, PUSH31, PUSH32:
pc.Add(pc, common.Big1)
a := int64(op) - int64(PUSH1) + 1
if int(pc.Int64()+a) > len(script) {
return nil
}
data := script[pc.Int64() : pc.Int64()+a]
if len(data) == 0 {
data = []byte{0}
}
asm = append(asm, fmt.Sprintf("0x%x", data))
pc.Add(pc, big.NewInt(a-1))
}
pc.Add(pc, common.Big1)
}
return
}