go-ethereum/cmd/ethereum/js.go
Felix Lange de86403f33 cmd/ethereum: fix JS REPL exit and add support for dumb terminals
It is now possible to exit the REPL using Ctrl-C, Ctrl-D or by typing "exit".
2015-03-06 13:08:11 +01:00

281 lines
6.3 KiB
Go

// Copyright (c) 2013-2014, Jeffrey Wilcke. All rights reserved.
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
//
// This 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
// General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this library; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
// MA 02110-1301 USA
package main
import (
"bufio"
"fmt"
"io/ioutil"
"os"
"os/signal"
"path"
"strings"
"github.com/ethereum/go-ethereum/cmd/utils"
"github.com/ethereum/go-ethereum/core/types"
"github.com/ethereum/go-ethereum/eth"
"github.com/ethereum/go-ethereum/ethutil"
"github.com/ethereum/go-ethereum/javascript"
"github.com/ethereum/go-ethereum/state"
"github.com/ethereum/go-ethereum/xeth"
"github.com/obscuren/otto"
"github.com/peterh/liner"
)
func execJsFile(ethereum *eth.Ethereum, filename string) {
file, err := os.Open(filename)
if err != nil {
utils.Fatalf("%v", err)
}
content, err := ioutil.ReadAll(file)
if err != nil {
utils.Fatalf("%v", err)
}
re := javascript.NewJSRE(xeth.New(ethereum))
if _, err := re.Run(string(content)); err != nil {
utils.Fatalf("Javascript Error: %v", err)
}
}
type repl struct {
re *javascript.JSRE
ethereum *eth.Ethereum
xeth *xeth.XEth
prompt string
lr *liner.State
}
func runREPL(ethereum *eth.Ethereum) {
xeth := xeth.New(ethereum)
repl := &repl{
re: javascript.NewJSRE(xeth),
xeth: xeth,
ethereum: ethereum,
prompt: "> ",
}
repl.initStdFuncs()
if !liner.TerminalSupported() {
repl.dumbRead()
} else {
lr := liner.NewLiner()
defer lr.Close()
lr.SetCtrlCAborts(true)
repl.withHistory(func(hist *os.File) { lr.ReadHistory(hist) })
repl.read(lr)
repl.withHistory(func(hist *os.File) { hist.Truncate(0); lr.WriteHistory(hist) })
}
}
func (self *repl) withHistory(op func(*os.File)) {
hist, err := os.OpenFile(path.Join(self.ethereum.DataDir, "history"), os.O_RDWR|os.O_CREATE, os.ModePerm)
if err != nil {
fmt.Printf("unable to open history file: %v\n", err)
return
}
op(hist)
hist.Close()
}
func (self *repl) parseInput(code string) {
defer func() {
if r := recover(); r != nil {
fmt.Println("[native] error", r)
}
}()
value, err := self.re.Run(code)
if err != nil {
fmt.Println(err)
return
}
self.printValue(value)
}
var indentCount = 0
var str = ""
func (self *repl) setIndent() {
open := strings.Count(str, "{")
open += strings.Count(str, "(")
closed := strings.Count(str, "}")
closed += strings.Count(str, ")")
indentCount = open - closed
if indentCount <= 0 {
self.prompt = "> "
} else {
self.prompt = strings.Join(make([]string, indentCount*2), "..")
self.prompt += " "
}
}
func (self *repl) read(lr *liner.State) {
for {
input, err := lr.Prompt(self.prompt)
if err != nil {
return
}
if input == "" {
continue
}
str += input + "\n"
self.setIndent()
if indentCount <= 0 {
if input == "exit" {
return
}
hist := str[:len(str)-1]
lr.AppendHistory(hist)
self.parseInput(str)
str = ""
}
}
}
func (self *repl) dumbRead() {
fmt.Println("Unsupported terminal, line editing will not work.")
// process lines
readDone := make(chan struct{})
go func() {
r := bufio.NewReader(os.Stdin)
loop:
for {
fmt.Print(self.prompt)
line, err := r.ReadString('\n')
switch {
case err != nil || line == "exit":
break loop
case line == "":
continue
default:
self.parseInput(line + "\n")
}
}
close(readDone)
}()
// wait for Ctrl-C
sigc := make(chan os.Signal, 1)
signal.Notify(sigc, os.Interrupt, os.Kill)
defer signal.Stop(sigc)
select {
case <-readDone:
case <-sigc:
os.Stdin.Close() // terminate read
}
}
func (self *repl) printValue(v interface{}) {
method, _ := self.re.Vm.Get("prettyPrint")
v, err := self.re.Vm.ToValue(v)
if err == nil {
val, err := method.Call(method, v)
if err == nil {
fmt.Printf("%v", val)
}
}
}
func (self *repl) initStdFuncs() {
t, _ := self.re.Vm.Get("eth")
eth := t.Object()
eth.Set("connect", self.connect)
eth.Set("stopMining", self.stopMining)
eth.Set("startMining", self.startMining)
eth.Set("dump", self.dump)
eth.Set("export", self.export)
}
/*
* The following methods are natively implemented javascript functions.
*/
func (self *repl) dump(call otto.FunctionCall) otto.Value {
var block *types.Block
if len(call.ArgumentList) > 0 {
if call.Argument(0).IsNumber() {
num, _ := call.Argument(0).ToInteger()
block = self.ethereum.ChainManager().GetBlockByNumber(uint64(num))
} else if call.Argument(0).IsString() {
hash, _ := call.Argument(0).ToString()
block = self.ethereum.ChainManager().GetBlock(ethutil.Hex2Bytes(hash))
} else {
fmt.Println("invalid argument for dump. Either hex string or number")
}
if block == nil {
fmt.Println("block not found")
return otto.UndefinedValue()
}
} else {
block = self.ethereum.ChainManager().CurrentBlock()
}
statedb := state.New(block.Root(), self.ethereum.Db())
v, _ := self.re.Vm.ToValue(statedb.RawDump())
return v
}
func (self *repl) stopMining(call otto.FunctionCall) otto.Value {
self.xeth.Miner().Stop()
return otto.TrueValue()
}
func (self *repl) startMining(call otto.FunctionCall) otto.Value {
self.xeth.Miner().Start()
return otto.TrueValue()
}
func (self *repl) connect(call otto.FunctionCall) otto.Value {
nodeURL, err := call.Argument(0).ToString()
if err != nil {
return otto.FalseValue()
}
if err := self.ethereum.SuggestPeer(nodeURL); err != nil {
return otto.FalseValue()
}
return otto.TrueValue()
}
func (self *repl) export(call otto.FunctionCall) otto.Value {
if len(call.ArgumentList) == 0 {
fmt.Println("err: require file name")
return otto.FalseValue()
}
fn, err := call.Argument(0).ToString()
if err != nil {
fmt.Println(err)
return otto.FalseValue()
}
data := self.ethereum.ChainManager().Export()
if err := ethutil.WriteFile(fn, data); err != nil {
fmt.Println(err)
return otto.FalseValue()
}
return otto.TrueValue()
}