go shell

gosh.go

package main

import (
	"bufio"
	"fmt"
	"log"
	"os"
	"os/exec"
	"strings"
)

type Command struct {
	Command   string
	Agruments []string
	Wait      bool
}

func main() {

	scanner := bufio.NewScanner(os.Stdin)
	input := true

	for input {
		fmt.Print("osh> ")

		input = scanner.Scan()
		if !input {
			break
		}

		text := scanner.Text()
		command := parse(text)
		run(command)

		//fmt.Printf("Command \"%s\", args \"%s\", wait : %t\n", command.Command, strings.Join(command.Agruments, " "), command.Wait)
	}
}

func parse(input string) Command {
	inputParts := strings.Split(strings.Trim(input, " "), " ")

	wait := inputParts[len(inputParts)-1] != "&"

	args := make([]string, len(inputParts)-1)
	lastIndex := len(inputParts)
	if !wait {
		lastIndex--
	}
	copy(args, inputParts[1:lastIndex])

	command := Command{Command: inputParts[0], Agruments: args, Wait: wait}
	return command
}

func run(command Command) {
	cmd := exec.Command(command.Command, command.Agruments...)
	cmd.Stdout = os.Stdout
	cmd.Stderr = os.Stderr

	if err := cmd.Start(); err != nil {
		log.Fatal(err)
	}

	if command.Wait {
		if err := cmd.Wait(); err != nil {
			log.Fatal(err)
		}
	}
}