From 5da644605377e01d3c1a4875000f139766c73f6a Mon Sep 17 00:00:00 2001
From: Dnomd343 <dnomd343@gmail.com>
Date: Sat, 16 Sep 2023 17:58:54 +0800
Subject: [PATCH] feat: process daemon framework

---
 next/main.go           | 23 ++++++++++++
 next/process/daemon.go | 83 ++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 106 insertions(+)
 create mode 100644 next/main.go
 create mode 100644 next/process/daemon.go

diff --git a/next/main.go b/next/main.go
new file mode 100644
index 0000000..ca1cb40
--- /dev/null
+++ b/next/main.go
@@ -0,0 +1,23 @@
+package main
+
+import (
+	"XProxy/next/process"
+	"time"
+)
+
+func main() {
+
+	//cmd := exec.Command("ls", "-al")
+	//cmd.Stdout = os.Stdout
+	//cmd.Stderr = os.Stderr
+	//err := cmd.Start()
+	//fmt.Println(err)
+	//err = cmd.Wait()
+	//fmt.Println(err)
+
+	p := process.NewDaemon("demo", []string{"sleep", "3"}, map[string]string{"DEBUG": "TRUE"})
+	p.Start()
+
+	time.Sleep(10 * time.Second)
+
+}
diff --git a/next/process/daemon.go b/next/process/daemon.go
new file mode 100644
index 0000000..1b270e4
--- /dev/null
+++ b/next/process/daemon.go
@@ -0,0 +1,83 @@
+package process
+
+import (
+	"fmt"
+	"os"
+	"os/exec"
+	"sync"
+)
+
+const (
+	Ready   = iota // process ready to start
+	Running        // process is running for now
+	Death          // process exited and waiting for restart
+	Stopped        // process has been stopped
+)
+
+type Process struct {
+	name   string
+	args   []string
+	envs   []string
+	mutex  sync.Mutex
+	proc   *exec.Cmd
+	status int
+}
+
+func NewDaemon(name string, command []string, env map[string]string) *Process {
+	fmt.Printf("Create new daemon task %s -> %v %v\n", name, command, env)
+	var envs []string
+	for k, v := range env {
+		envs = append(envs, fmt.Sprintf("%s=%s", k, v))
+	}
+	return &Process{
+		name:   name,
+		envs:   envs,
+		args:   command,
+		status: Ready,
+	}
+}
+
+func (p *Process) boot() bool {
+	p.proc = exec.Command(p.args[0], p.args[1:]...)
+	p.proc.Stdout = os.Stdout
+	p.proc.Stderr = os.Stderr
+	if len(p.envs) != 0 { // with custom env variables
+		p.proc.Env = p.envs
+	}
+	err := p.proc.Start()
+	if err != nil {
+		fmt.Printf("Failed to boot process %s -> %v\n", p.name, err)
+		p.status = Stopped
+		return false
+	}
+	fmt.Printf("Successfully executed process %s -> PID = %d\n", p.name, p.proc.Process.Pid)
+	p.status = Running
+	return true
+}
+
+func (p *Process) wait() {
+	for p.proc.ProcessState == nil { // wait until exit
+		p.proc.Wait()
+	}
+	fmt.Printf("Catch process %s exit", p.name)
+}
+
+func (p *Process) Start() {
+	if !p.mutex.TryLock() {
+		fmt.Printf("already running")
+		return
+	}
+
+	// TODO: daemon logical
+	p.boot()
+	p.wait()
+
+}
+
+func (p *Process) Status() int {
+	return p.status
+}
+
+func (p *Process) Stop() {
+	// TODO: stop daemon and kill process
+}