golang 守护进程（daemon）实例（二）——加载任意进程

前期实现

-daemon-forever

更进一步思考

我们可以不局限于 Go 代码层面的守护进程，而是实现对任意进程的守护进程创建，从而对所有 Linux 环境的程序都可以进行加载。

需求

-progDoSomething

实现

关键点

1. 为实现兼容不同操作系统，对操作系统类型进行了判断

daemonforeverdaemoncmd

switch runtime.GOOS { 
	case "darwin": 
		cmd = exec.Command(os.Getenv("SHELL"), "-c", args[0])
		break
	case "linux": 
		cmd = exec.Command(os.Getenv("SHELL"), "-c", args[0])
		break
	case "windows": 
		cmd = exec.Command("cmd", "/C", args[0])
		break
	default:
		os.Exit(0)
		break
}

cmd.Wait()

cmd = SubProcess([]string{*program}, true)
cmd.Wait()

foreverfor-prog

for {
	fmt.Printf("[*] Forever running in PID: %d PPID: %d\n", os.Getpid(), os.Getppid())
	cmd = SubProcess(StripSlice(args, "-"+FOREVER), false)
	cmd.Wait()
}

go-daemon-loader.go

直接上代码

package main

import (
	"os"
	"os/exec"
	"fmt"
	"flag"
	"runtime"
)

const (
	PROGRAM = "prog"
	DAEMON = "daemon"
	FOREVER = "forever"
)

func StripSlice(slice []string, element string) []string {
	for i := 0; i < len(slice); {
		if slice[i] == element && i != len(slice)-1 {
			slice = append(slice[:i], slice[i+1:]...)
			break
		} else if slice[i] == element && i == len(slice)-1 {
			slice = slice[:i]
			break
		} else {
			i++
		}
	}
	return slice
}

func SubProcess(args []string, shell bool) *exec.Cmd {
	var cmd *exec.Cmd
	if shell { 
		switch runtime.GOOS { 
		case "darwin": 
			cmd = exec.Command(os.Getenv("SHELL"), "-c", args[0])
			break
		case "linux": 
			cmd = exec.Command(os.Getenv("SHELL"), "-c", args[0])
			break
		case "windows": 
			cmd = exec.Command("cmd", "/C", args[0])
			break
		default:
			os.Exit(1)
			break
		}
	} else {
		cmd = exec.Command(args[0], args[1:]...)
	}
	cmd.Stdin = os.Stdin
	cmd.Stdout = os.Stdout
	cmd.Stderr = os.Stderr
	err := cmd.Start()
	if err != nil {
		fmt.Fprintf(os.Stderr, "[-] Error: %s\n", err)
	}
	return cmd
}

func main(){
	var cmd *exec.Cmd
	program := flag.String(PROGRAM, "", "run program")
	daemon := flag.Bool(DAEMON, false, "run in daemon")
	forever := flag.Bool(FOREVER, false, "run forever")
	flag.Parse()
	fmt.Printf("[*] PID: %d PPID: %d ARG: %s PROG:\"%s\"\n", os.Getpid(), os.Getppid(), os.Args, *program)
	if *program == "" {
		flag.Usage()
		os.Exit(1)
	}
	if *daemon {
		fmt.Printf("[*] Daemon running in PID: %d PPID: %d\n", os.Getpid(), os.Getppid())
		SubProcess(StripSlice(os.Args, "-"+DAEMON), false)
		os.Exit(0)
	} else if *forever {
		args := os.Args
		for {
			fmt.Printf("[*] Forever running in PID: %d PPID: %d\n", os.Getpid(), os.Getppid())
			cmd = SubProcess(StripSlice(args, "-"+FOREVER), false)
			cmd.Wait()
		}
		os.Exit(0)
	} else {
		fmt.Printf("[*] Service running in PID: %d PPID: %d\n", os.Getpid(), os.Getppid())
		cmd = SubProcess([]string{*program}, true)
		cmd.Wait()
	}
}

使用

编译

• Linux 编译（同 MacOS 编译，未测试）

go build -ldflags "-s -w" ./go-daemon-loader.go

• Windows 编译

go build -ldflags "-s -w" .\go-daemon-loader.go

运行

• Linux

./go-daemon-loader -prog "ping 127.0.0.1" -daemon -forever

• Windows

.\go-daemon-loader.exe -prog "ping 127.0.0.1 -t" -daemon -forever