golang.org/x/sys@v0.9.0/windows/svc/example/service.go (about)

     1  // Copyright 2012 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  //go:build windows
     6  // +build windows
     7  
     8  package main
     9  
    10  import (
    11  	"fmt"
    12  	"strings"
    13  	"time"
    14  
    15  	"golang.org/x/sys/windows/svc"
    16  	"golang.org/x/sys/windows/svc/debug"
    17  	"golang.org/x/sys/windows/svc/eventlog"
    18  )
    19  
    20  var elog debug.Log
    21  
    22  type exampleService struct{}
    23  
    24  func (m *exampleService) Execute(args []string, r <-chan svc.ChangeRequest, changes chan<- svc.Status) (ssec bool, errno uint32) {
    25  	const cmdsAccepted = svc.AcceptStop | svc.AcceptShutdown | svc.AcceptPauseAndContinue
    26  	changes <- svc.Status{State: svc.StartPending}
    27  	fasttick := time.Tick(500 * time.Millisecond)
    28  	slowtick := time.Tick(2 * time.Second)
    29  	tick := fasttick
    30  	changes <- svc.Status{State: svc.Running, Accepts: cmdsAccepted}
    31  loop:
    32  	for {
    33  		select {
    34  		case <-tick:
    35  			beep()
    36  			elog.Info(1, "beep")
    37  		case c := <-r:
    38  			switch c.Cmd {
    39  			case svc.Interrogate:
    40  				changes <- c.CurrentStatus
    41  				// Testing deadlock from https://code.google.com/p/winsvc/issues/detail?id=4
    42  				time.Sleep(100 * time.Millisecond)
    43  				changes <- c.CurrentStatus
    44  			case svc.Stop, svc.Shutdown:
    45  				// golang.org/x/sys/windows/svc.TestExample is verifying this output.
    46  				testOutput := strings.Join(args, "-")
    47  				testOutput += fmt.Sprintf("-%d", c.Context)
    48  				elog.Info(1, testOutput)
    49  				break loop
    50  			case svc.Pause:
    51  				changes <- svc.Status{State: svc.Paused, Accepts: cmdsAccepted}
    52  				tick = slowtick
    53  			case svc.Continue:
    54  				changes <- svc.Status{State: svc.Running, Accepts: cmdsAccepted}
    55  				tick = fasttick
    56  			default:
    57  				elog.Error(1, fmt.Sprintf("unexpected control request #%d", c))
    58  			}
    59  		}
    60  	}
    61  	changes <- svc.Status{State: svc.StopPending}
    62  	return
    63  }
    64  
    65  func runService(name string, isDebug bool) {
    66  	var err error
    67  	if isDebug {
    68  		elog = debug.New(name)
    69  	} else {
    70  		elog, err = eventlog.Open(name)
    71  		if err != nil {
    72  			return
    73  		}
    74  	}
    75  	defer elog.Close()
    76  
    77  	elog.Info(1, fmt.Sprintf("starting %s service", name))
    78  	run := svc.Run
    79  	if isDebug {
    80  		run = debug.Run
    81  	}
    82  	err = run(name, &exampleService{})
    83  	if err != nil {
    84  		elog.Error(1, fmt.Sprintf("%s service failed: %v", name, err))
    85  		return
    86  	}
    87  	elog.Info(1, fmt.Sprintf("%s service stopped", name))
    88  }