windows.go

// +build windows

package initme

import (
	"errors"
	"fmt"
	"time"

	"golang.org/x/sys/windows/svc"
)

func init() {
	serviceType = WindowsService{}
}

type WindowsService struct {
	Conf Config
}

func (self WindowsService) New(c Config) Service {

	self.Conf = c

	return self
}

func (self WindowsService) Register() (output string, err error, code int) {
	args, err := self.buildScArgs("create")
	if err != nil {
		return
	}
	return execute(self.Conf.Log, "sc.exe", args...)
}

func (self WindowsService) Start() (output string, err error, code int) {
	return execute(self.Conf.Log, "sc.exe", "start", self.Conf.Name)
}

func (self WindowsService) Stop() (output string, err error, code int) {
	return execute(self.Conf.Log, "sc.exe", "stop", self.Conf.Name)
}

func (self WindowsService) Status() (output string, err error, code int) {
	return execute(self.Conf.Log, "sc.exe", "query", self.Conf.Name)
}

func (self WindowsService) Disable() (output string, err error, code int) {
	return execute(self.Conf.Log, "sc.exe", "config", self.Conf.Name, "start=", "disabled")
}

func (self WindowsService) Delete() (output string, err error, code int) {
	return execute(self.Conf.Log, "sc.exe", "delete", self.Conf.Name)
}

// https://support.microsoft.com/en-us/kb/251192
func (self WindowsService) buildScArgs(init ...string) (args []string, err error) {
	args = make([]string, 0)

	args = append(args, init...)

	if self.Conf.Name != "" {
		args = append(args, self.Conf.Name)
	} else {
		return nil, errors.New("Name is mandatory")
	}
	if self.Conf.Type != "" {
		args = append(args, "type=", self.Conf.Type)
	}
	if self.Conf.StartType != "" {
		args = append(args, "start=", self.Conf.StartType)
	}
	if self.Conf.Error != "" {
		args = append(args, "error=", self.Conf.Error)
	}
	if self.Conf.BinPath != "" {
		args = append(args, "binpath=", self.Conf.BinPath)
	} else {
		return nil, errors.New("BinPath is mandatory")
	}
	if self.Conf.Group != "" {
		args = append(args, "group=", self.Conf.Group)
	}
	if self.Conf.Tag != "" {
		args = append(args, "tag=", self.Conf.Tag)
	}
	if self.Conf.Depend != "" {
		args = append(args, "depend=", self.Conf.Depend)
	}
	if self.Conf.Obj != "" {
		if self.Conf.Password != "" {
			return nil, errors.New("Password is mandatory if Obj is set")
		}
		args = append(args, "obj=", self.Conf.Obj)
	}
	if self.Conf.DisplayName != "" {
		args = append(args, "DisplayName=", self.Conf.DisplayName)
	}
	if self.Conf.Password != "" {
		if self.Conf.Obj != "" {
			return nil, errors.New("Password is meanful only if Obj is set")
		}
		args = append(args, "password=", self.Conf.Password)
	}

	return
}

func (self WindowsService) IsAnInteractiveSession() (bool, error) {
	return svc.IsAnInteractiveSession()
}

func (self WindowsService) Run() {
	svc.Run(self.Conf.Name, self)
}

func (self WindowsService) Execute(args []string, r <-chan svc.ChangeRequest, changes chan<- svc.Status) (ssec bool, errno uint32) {
	const cmdsAccepted = svc.AcceptStop | svc.AcceptShutdown | svc.AcceptPauseAndContinue
	changes <- svc.Status{State: svc.StartPending}
	fasttick := time.Tick(500 * time.Millisecond)
	slowtick := time.Tick(2 * time.Second)
	tick := fasttick
	changes <- svc.Status{State: svc.Running, Accepts: cmdsAccepted}

	go self.Conf.Job()

loop:
	for {
		select {
		case <-tick:

			//self.eventLog.Info(1, "beep")
		case c := <-r:
			switch c.Cmd {
			case svc.Interrogate:
				changes <- c.CurrentStatus
				// Testing deadlock from https://code.google.com/p/winsvc/issues/detail?id=4
				time.Sleep(100 * time.Millisecond)
				changes <- c.CurrentStatus
			case svc.Stop, svc.Shutdown:
				break loop
			case svc.Pause:
				changes <- svc.Status{State: svc.Paused, Accepts: cmdsAccepted}
				tick = slowtick
			case svc.Continue:
				changes <- svc.Status{State: svc.Running, Accepts: cmdsAccepted}
				tick = fasttick
			default:
				self.Conf.Log.Println(fmt.Sprintf("unexpected control request #%d", c))
			}
		}
	}
	changes <- svc.Status{State: svc.StopPending}
	return
}