Hilbish/exec.go

617 lines
14 KiB
Go

package main
import (
"bytes"
"context"
"errors"
"os/exec"
"fmt"
"io"
"os"
"os/signal"
"path/filepath"
"runtime"
"strings"
"syscall"
"time"
"hilbish/util"
rt "github.com/arnodel/golua/runtime"
"mvdan.cc/sh/v3/shell"
//"github.com/yuin/gopher-lua/parse"
"mvdan.cc/sh/v3/interp"
"mvdan.cc/sh/v3/syntax"
"mvdan.cc/sh/v3/expand"
)
var errNotExec = errors.New("not executable")
var errNotFound = errors.New("not found")
var runnerMode rt.Value = rt.StringValue("hybrid")
type streams struct {
stdout io.Writer
stderr io.Writer
stdin io.Reader
}
type execError struct{
typ string
cmd string
code int
colon bool
err error
}
func (e execError) Error() string {
return fmt.Sprintf("%s: %s", e.cmd, e.typ)
}
func (e execError) sprint() error {
sep := " "
if e.colon {
sep = ": "
}
return fmt.Errorf("hilbish: %s%s%s", e.cmd, sep, e.err.Error())
}
func isExecError(err error) (execError, bool) {
if exErr, ok := err.(execError); ok {
return exErr, true
}
fields := strings.Split(err.Error(), ": ")
knownTypes := []string{
"not-found",
"not-executable",
}
if len(fields) > 1 && contains(knownTypes, fields[1]) {
var colon bool
var e error
switch fields[1] {
case "not-found":
e = errNotFound
case "not-executable":
colon = true
e = errNotExec
}
return execError{
cmd: fields[0],
typ: fields[1],
colon: colon,
err: e,
}, true
}
return execError{}, false
}
func runInput(input string, priv bool) {
running = true
cmdString := aliases.Resolve(input)
hooks.Emit("command.preexec", input, cmdString)
rerun:
var exitCode uint8
var err error
var cont bool
// save incase it changes while prompting (For some reason)
currentRunner := runnerMode
if currentRunner.Type() == rt.StringType {
switch currentRunner.AsString() {
case "hybrid":
_, _, err = handleLua(input)
if err == nil {
cmdFinish(0, input, priv)
return
}
input, exitCode, cont, err = handleSh(input)
case "hybridRev":
_, _, _, err = handleSh(input)
if err == nil {
cmdFinish(0, input, priv)
return
}
input, exitCode, err = handleLua(input)
case "lua":
input, exitCode, err = handleLua(input)
case "sh":
input, exitCode, cont, err = handleSh(input)
}
} else {
// can only be a string or function so
var runnerErr error
input, exitCode, cont, runnerErr, err = runLuaRunner(currentRunner, input)
if err != nil {
fmt.Fprintln(os.Stderr, err)
cmdFinish(124, input, priv)
return
}
// yep, we only use `err` to check for lua eval error
// our actual error should only be a runner provided error at this point
// command not found type, etc
err = runnerErr
}
if cont {
input, err = reprompt(input)
if err == nil {
goto rerun
} else if err == io.EOF {
return
}
}
if err != nil {
if exErr, ok := isExecError(err); ok {
hooks.Emit("command." + exErr.typ, exErr.cmd)
} else {
fmt.Fprintln(os.Stderr, err)
}
}
cmdFinish(exitCode, input, priv)
}
func reprompt(input string) (string, error) {
for {
in, err := continuePrompt(strings.TrimSuffix(input, "\\"))
if err != nil {
lr.SetPrompt(fmtPrompt(prompt))
return input, err
}
if strings.HasSuffix(in, "\\") {
continue
}
return in, nil
}
}
func runLuaRunner(runr rt.Value, userInput string) (input string, exitCode uint8, continued bool, runnerErr, err error) {
term := rt.NewTerminationWith(l.MainThread().CurrentCont(), 3, false)
err = rt.Call(l.MainThread(), runr, []rt.Value{rt.StringValue(userInput)}, term)
if err != nil {
return "", 124, false, nil, err
}
var runner *rt.Table
var ok bool
runnerRet := term.Get(0)
if runner, ok = runnerRet.TryTable(); !ok {
fmt.Fprintln(os.Stderr, "runner did not return a table")
exitCode = 125
input = userInput
return
}
if code, ok := runner.Get(rt.StringValue("exitCode")).TryInt(); ok {
exitCode = uint8(code)
}
if inp, ok := runner.Get(rt.StringValue("input")).TryString(); ok {
input = inp
}
if errStr, ok := runner.Get(rt.StringValue("err")).TryString(); ok {
runnerErr = fmt.Errorf("%s", errStr)
}
if c, ok := runner.Get(rt.StringValue("continue")).TryBool(); ok {
continued = c
}
return
}
func handleLua(input string) (string, uint8, error) {
cmdString := aliases.Resolve(input)
// First try to load input, essentially compiling to bytecode
chunk, err := l.CompileAndLoadLuaChunk("", []byte(cmdString), rt.TableValue(l.GlobalEnv()))
if err != nil && noexecute {
fmt.Println(err)
/* if lerr, ok := err.(*lua.ApiError); ok {
if perr, ok := lerr.Cause.(*parse.Error); ok {
print(perr.Pos.Line == parse.EOF)
}
}
*/
return cmdString, 125, err
}
// And if there's no syntax errors and -n isnt provided, run
if !noexecute {
if chunk != nil {
_, err = rt.Call1(l.MainThread(), rt.FunctionValue(chunk))
}
}
if err == nil {
return cmdString, 0, nil
}
return cmdString, 125, err
}
func handleSh(cmdString string) (input string, exitCode uint8, cont bool, runErr error) {
shRunner := hshMod.Get(rt.StringValue("runner")).AsTable().Get(rt.StringValue("sh"))
var err error
input, exitCode, cont, runErr, err = runLuaRunner(shRunner, cmdString)
if err != nil {
runErr = err
}
return
}
func execSh(cmdString string) (string, uint8, bool, error) {
_, _, err := execCommand(cmdString, nil)
if err != nil {
// If input is incomplete, start multiline prompting
if syntax.IsIncomplete(err) {
if !interactive {
return cmdString, 126, false, err
}
return cmdString, 126, true, err
} else {
if code, ok := interp.IsExitStatus(err); ok {
return cmdString, code, false, nil
} else {
return cmdString, 126, false, err
}
}
}
return cmdString, 0, false, nil
}
// Run command in sh interpreter
func execCommand(cmd string, strms *streams) (io.Writer, io.Writer, error) {
file, err := syntax.NewParser().Parse(strings.NewReader(cmd), "")
if err != nil {
return nil, nil, err
}
runner, _ := interp.New()
if strms == nil {
strms = &streams{}
}
if strms.stdout == nil {
strms.stdout = os.Stdout
}
if strms.stderr == nil {
strms.stderr = os.Stderr
}
if strms.stdin == nil {
strms.stdin = os.Stdin
}
interp.StdIO(strms.stdin, strms.stdout, strms.stderr)(runner)
buf := new(bytes.Buffer)
printer := syntax.NewPrinter()
var bg bool
for _, stmt := range file.Stmts {
bg = false
if stmt.Background {
bg = true
printer.Print(buf, stmt.Cmd)
stmtStr := buf.String()
buf.Reset()
jobs.add(stmtStr, []string{}, "")
}
interp.ExecHandler(execHandle(bg))(runner)
err = runner.Run(context.TODO(), stmt)
if err != nil {
return strms.stdout, strms.stderr, err
}
}
return strms.stdout, strms.stderr, nil
}
func execHandle(bg bool) interp.ExecHandlerFunc {
return func(ctx context.Context, args []string) error {
_, argstring := splitInput(strings.Join(args, " "))
// i dont really like this but it works
if aliases.All()[args[0]] != "" {
for i, arg := range args {
if strings.Contains(arg, " ") {
args[i] = fmt.Sprintf("\"%s\"", arg)
}
}
_, argstring = splitInput(strings.Join(args, " "))
// If alias was found, use command alias
argstring = aliases.Resolve(argstring)
var err error
args, err = shell.Fields(argstring, nil)
if err != nil {
return err
}
}
// If command is defined in Lua then run it
luacmdArgs := rt.NewTable()
for i, str := range args[1:] {
luacmdArgs.Set(rt.IntValue(int64(i + 1)), rt.StringValue(str))
}
hc := interp.HandlerCtx(ctx)
if cmd := cmds.Commands[args[0]]; cmd != nil {
stdin := newSinkInput(hc.Stdin)
stdout := newSinkOutput(hc.Stdout)
stderr := newSinkOutput(hc.Stderr)
sinks := rt.NewTable()
sinks.Set(rt.StringValue("in"), rt.UserDataValue(stdin.ud))
sinks.Set(rt.StringValue("input"), rt.UserDataValue(stdin.ud))
sinks.Set(rt.StringValue("out"), rt.UserDataValue(stdout.ud))
sinks.Set(rt.StringValue("err"), rt.UserDataValue(stderr.ud))
t := rt.NewThread(l)
sig := make(chan os.Signal)
exit := make(chan bool)
luaexitcode := rt.IntValue(63)
var err error
go func() {
defer func() {
if r := recover(); r != nil {
exit <- true
}
}()
signal.Notify(sig, os.Interrupt)
select {
case <-sig:
t.KillContext()
return
}
}()
go func() {
luaexitcode, err = rt.Call1(t, rt.FunctionValue(cmd), rt.TableValue(luacmdArgs), rt.TableValue(sinks))
exit <- true
}()
<-exit
if err != nil {
fmt.Fprintln(os.Stderr, "Error in command:\n" + err.Error())
return interp.NewExitStatus(1)
}
var exitcode uint8
if code, ok := luaexitcode.TryInt(); ok {
exitcode = uint8(code)
} else if luaexitcode != rt.NilValue {
// deregister commander
delete(cmds.Commands, args[0])
fmt.Fprintf(os.Stderr, "Commander did not return number for exit code. %s, you're fired.\n", args[0])
}
return interp.NewExitStatus(exitcode)
}
err := lookpath(args[0])
if err == errNotExec {
return execError{
typ: "not-executable",
cmd: args[0],
code: 126,
colon: true,
err: errNotExec,
}
} else if err != nil {
return execError{
typ: "not-found",
cmd: args[0],
code: 127,
err: errNotFound,
}
}
killTimeout := 2 * time.Second
// from here is basically copy-paste of the default exec handler from
// sh/interp but with our job handling
path, err := interp.LookPathDir(hc.Dir, hc.Env, args[0])
if err != nil {
fmt.Fprintln(hc.Stderr, err)
return interp.NewExitStatus(127)
}
env := hc.Env
envList := make([]string, 0, 64)
env.Each(func(name string, vr expand.Variable) bool {
if !vr.IsSet() {
// If a variable is set globally but unset in the
// runner, we need to ensure it's not part of the final
// list. Seems like zeroing the element is enough.
// This is a linear search, but this scenario should be
// rare, and the number of variables shouldn't be large.
for i, kv := range envList {
if strings.HasPrefix(kv, name+"=") {
envList[i] = ""
}
}
}
if vr.Exported && vr.Kind == expand.String {
envList = append(envList, name+"="+vr.String())
}
return true
})
cmd := exec.Cmd{
Path: path,
Args: args,
Env: envList,
Dir: hc.Dir,
Stdin: hc.Stdin,
Stdout: hc.Stdout,
Stderr: hc.Stderr,
}
var j *job
if bg {
j = jobs.getLatest()
j.setHandle(&cmd)
err = j.start()
} else {
err = cmd.Start()
}
if err == nil {
if done := ctx.Done(); done != nil {
go func() {
<-done
if killTimeout <= 0 || runtime.GOOS == "windows" {
cmd.Process.Signal(os.Kill)
return
}
// TODO: don't temporarily leak this goroutine
// if the program stops itself with the
// interrupt.
go func() {
time.Sleep(killTimeout)
cmd.Process.Signal(os.Kill)
}()
cmd.Process.Signal(os.Interrupt)
}()
}
err = cmd.Wait()
}
exit := handleExecErr(err)
if bg {
j.exitCode = int(exit)
j.finish()
}
return interp.NewExitStatus(exit)
}
}
func handleExecErr(err error) (exit uint8) {
ctx := context.TODO()
switch x := err.(type) {
case *exec.ExitError:
// started, but errored - default to 1 if OS
// doesn't have exit statuses
if status, ok := x.Sys().(syscall.WaitStatus); ok {
if status.Signaled() {
if ctx.Err() != nil {
return
}
exit = uint8(128 + status.Signal())
return
}
exit = uint8(status.ExitStatus())
return
}
exit = 1
return
case *exec.Error:
// did not start
//fmt.Fprintf(hc.Stderr, "%v\n", err)
exit = 127
default: return
}
return
}
func lookpath(file string) error { // custom lookpath function so we know if a command is found *and* is executable
var skip []string
if runtime.GOOS == "windows" {
skip = []string{"./", "../", "~/", "C:"}
} else {
skip = []string{"./", "/", "../", "~/"}
}
for _, s := range skip {
if strings.HasPrefix(file, s) {
return findExecutable(file, false, false)
}
}
for _, dir := range filepath.SplitList(os.Getenv("PATH")) {
path := filepath.Join(dir, file)
err := findExecutable(path, true, false)
if err == errNotExec {
return err
} else if err == nil {
return nil
}
}
return os.ErrNotExist
}
func splitInput(input string) ([]string, string) {
// end my suffering
// TODO: refactor this garbage
quoted := false
startlastcmd := false
lastcmddone := false
cmdArgs := []string{}
sb := &strings.Builder{}
cmdstr := &strings.Builder{}
lastcmd := "" //readline.GetHistory(readline.HistorySize() - 1)
for _, r := range input {
if r == '"' {
// start quoted input
// this determines if other runes are replaced
quoted = !quoted
// dont add back quotes
//sb.WriteRune(r)
} else if !quoted && r == '~' {
// if not in quotes and ~ is found then make it $HOME
sb.WriteString(os.Getenv("HOME"))
} else if !quoted && r == ' ' {
// if not quoted and there's a space then add to cmdargs
cmdArgs = append(cmdArgs, sb.String())
sb.Reset()
} else if !quoted && r == '^' && startlastcmd && !lastcmddone {
// if ^ is found, isnt in quotes and is
// the second occurence of the character and is
// the first time "^^" has been used
cmdstr.WriteString(lastcmd)
sb.WriteString(lastcmd)
startlastcmd = !startlastcmd
lastcmddone = !lastcmddone
continue
} else if !quoted && r == '^' && !lastcmddone {
// if ^ is found, isnt in quotes and is the
// first time of starting "^^"
startlastcmd = !startlastcmd
continue
} else {
sb.WriteRune(r)
}
cmdstr.WriteRune(r)
}
if sb.Len() > 0 {
cmdArgs = append(cmdArgs, sb.String())
}
return cmdArgs, cmdstr.String()
}
func cmdFinish(code uint8, cmdstr string, private bool) {
util.SetField(l, hshMod, "exitCode", rt.IntValue(int64(code)))
// using AsValue (to convert to lua type) on an interface which is an int
// results in it being unknown in lua .... ????
// so we allow the hook handler to take lua runtime Values
hooks.Emit("command.exit", rt.IntValue(int64(code)), cmdstr, private)
}