vendor/golang.org/x/sys/windows/svc/example/service.go

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