github.com/clem109/go-ethereum@v1.8.3-0.20180316121352-fe6cf00f480a/cmd/evm/disasm.go (about)

     1  // Copyright 2017 The go-ethereum Authors
     2  // This file is part of go-ethereum.
     3  //
     4  // go-ethereum is free software: you can redistribute it and/or modify
     5  // it under the terms of the GNU General Public License as published by
     6  // the Free Software Foundation, either version 3 of the License, or
     7  // (at your option) any later version.
     8  //
     9  // go-ethereum is distributed in the hope that it will be useful,
    10  // but WITHOUT ANY WARRANTY; without even the implied warranty of
    11  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
    12  // GNU General Public License for more details.
    13  //
    14  // You should have received a copy of the GNU General Public License
    15  // along with go-ethereum. If not, see <http://www.gnu.org/licenses/>.
    16  
    17  package main
    18  
    19  import (
    20  	"errors"
    21  	"fmt"
    22  	"io/ioutil"
    23  	"strings"
    24  
    25  	"github.com/ethereum/go-ethereum/core/asm"
    26  	cli "gopkg.in/urfave/cli.v1"
    27  )
    28  
    29  var disasmCommand = cli.Command{
    30  	Action:    disasmCmd,
    31  	Name:      "disasm",
    32  	Usage:     "disassembles evm binary",
    33  	ArgsUsage: "<file>",
    34  }
    35  
    36  func disasmCmd(ctx *cli.Context) error {
    37  	if len(ctx.Args().First()) == 0 {
    38  		return errors.New("filename required")
    39  	}
    40  
    41  	fn := ctx.Args().First()
    42  	in, err := ioutil.ReadFile(fn)
    43  	if err != nil {
    44  		return err
    45  	}
    46  
    47  	code := strings.TrimSpace(string(in[:]))
    48  	fmt.Printf("%v\n", code)
    49  	return asm.PrintDisassembled(code)
    50  }