Hilbish/exec.go

521 lines
12 KiB
Go

package main
import (
"bytes"
"context"
"errors"
"os/exec"
"fmt"
"io"
"os"
"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 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.Em.Emit("command.preexec", input, cmdString)
var exitCode uint8
var err error
if runnerMode.Type() == rt.StringType {
switch runnerMode.AsString() {
case "hybrid":
_, _, err = handleLua(cmdString)
if err == nil {
cmdFinish(0, input, priv)
return
}
input, exitCode, err = handleSh(input)
case "hybridRev":
_, _, err = handleSh(input)
if err == nil {
cmdFinish(0, input, priv)
return
}
input, exitCode, err = handleLua(cmdString)
case "lua":
input, exitCode, err = handleLua(cmdString)
case "sh":
input, exitCode, err = handleSh(input)
}
} else {
// can only be a string or function so
term := rt.NewTerminationWith(l.MainThread().CurrentCont(), 3, false)
err = rt.Call(l.MainThread(), runnerMode, []rt.Value{rt.StringValue(input)}, term)
if err != nil {
fmt.Fprintln(os.Stderr, err)
cmdFinish(124, input, priv)
return
}
luaInput := term.Get(0)
luaexitcode := term.Get(1)
runErr := term.Get(2)
if code, ok := luaexitcode.TryInt(); ok {
exitCode = uint8(code)
}
if inp, ok := luaInput.TryString(); ok {
input = inp
}
if errStr, ok := runErr.TryString(); ok {
err = fmt.Errorf("%s", errStr)
}
}
if err != nil {
if exErr, ok := isExecError(err); ok {
hooks.Em.Emit("command." + exErr.typ, exErr.cmd)
err = exErr.sprint()
}
fmt.Fprintln(os.Stderr, err)
}
cmdFinish(exitCode, input, priv)
}
func handleLua(cmdString string) (string, uint8, error) {
// 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) (string, uint8, error) {
_, _, err := execCommand(cmdString, true)
if err != nil {
// If input is incomplete, start multiline prompting
if syntax.IsIncomplete(err) {
if !interactive {
return cmdString, 126, err
}
for {
cmdString, err = continuePrompt(strings.TrimSuffix(cmdString, "\\"))
if err != nil {
break
}
_, _, err = execCommand(cmdString, true)
if syntax.IsIncomplete(err) || strings.HasSuffix(cmdString, "\\") {
continue
} else if code, ok := interp.IsExitStatus(err); ok {
return cmdString, code, nil
} else if err != nil {
return cmdString, 126, err
} else {
return cmdString, 0, nil
}
}
} else {
if code, ok := interp.IsExitStatus(err); ok {
return cmdString, code, nil
} else {
return cmdString, 126, err
}
}
}
return cmdString, 0, nil
}
// Run command in sh interpreter
func execCommand(cmd string, terminalOut bool) (io.Writer, io.Writer, error) {
file, err := syntax.NewParser().Parse(strings.NewReader(cmd), "")
if err != nil {
return nil, nil, err
}
runner, _ := interp.New()
var stdout io.Writer
var stderr io.Writer
if terminalOut {
interp.StdIO(os.Stdin, os.Stdout, os.Stderr)(runner)
} else {
stdout = new(bytes.Buffer)
stderr = new(bytes.Buffer)
interp.StdIO(os.Stdin, stdout, 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 stdout, stderr, err
}
}
return stdout, 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))
}
if commands[args[0]] != nil {
luaexitcode, err := rt.Call1(l.MainThread(), rt.FunctionValue(commands[args[0]]), rt.TableValue(luacmdArgs))
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(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
hc := interp.HandlerCtx(ctx)
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) {
// if input has space at the beginning, dont put in history
if interactive && !private {
handleHistory(cmdstr)
}
util.SetField(l, hshMod, "exitCode", rt.IntValue(int64(code)), "Exit code of last exected command")
// 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.Em.Emit("command.exit", rt.IntValue(int64(code)), cmdstr)
}