[windows]service: add windows service feature

winservices/manager.go

+// +build windows
+
+package winservices
+
+import (
+	"golang.org/x/sys/windows/svc/mgr"
+)
+
+type scmanager struct {
+	mgr *mgr.Mgr
+}
+
+func openSCManager() (*scmanager, error) {
+	m, err := mgr.Connect()
+	if err != nil {
+		return nil, err
+	}
+	return &scmanager{m}, nil
+}
+
+func (sc *scmanager) close() error {
+	return sc.mgr.Disconnect()
+}
+
+func getService(serviceName string) (*mgr.Service, error) {
+	m, err := openSCManager()
+	if err != nil {
+		return nil, err
+	}
+	defer m.close()
+	return m.mgr.OpenService(serviceName)
+}

winservices/winservices.go

+// +build windows
+
+package winservices
+
+import (
+	"context"
+	"unsafe"
+
+	"golang.org/x/sys/windows"
+	"golang.org/x/sys/windows/svc"
+	"golang.org/x/sys/windows/svc/mgr"
+)
+
+// Service represent a windows service.
+type Service struct {
+	Name   string
+	Config mgr.Config
+	Status ServiceStatus
+	srv    *mgr.Service
+}
+
+// ServiceStatus combines State and Accepted commands to fully describe running service.
+type ServiceStatus struct {
+	State         svc.State
+	Accepts       svc.Accepted
+	Pid           uint32
+	Win32ExitCode uint32
+}
+
+// NewService create and return a windows Service
+func NewService(name string) (*Service, error) {
+	// call windows service function need to OpenService handler,
+	// so first call func OpenService to get the specified service handler.
+	service, err := getService(name)
+	if err != nil {
+		return nil, err
+	}
+	return &Service{
+		Name: name,
+		srv:  service,
+	}, nil
+}
+
+// GetServiceDetail get a windows service by name
+func (s *Service) GetServiceDetail() error {
+	return s.GetServiceDetailWithContext(context.Background())
+}
+
+// GetServiceDetailWithContext get a windows service by name
+func (s *Service) GetServiceDetailWithContext(ctx context.Context) error {
+	config, err := s.QueryServiceConfigWithContext(ctx)
+	if err != nil {
+		return err
+	}
+	s.Config = config
+
+	status, err := s.QueryStatusWithContext(ctx)
+	if err != nil {
+		return err
+	}
+	s.Status = status
+
+	return nil
+}
+
+// QueryServiceConfig return the specified service config
+func (s *Service) QueryServiceConfig() (mgr.Config, error) {
+	return s.QueryServiceConfigWithContext(context.Background())
+}
+
+// QueryServiceConfigWithContext call QueryServiceConfig() and QueryServiceConfig2()
+// implement windows https://msdn.microsoft.com/en-us/library/windows/desktop/ms684932(v=vs.85).aspx
+func (s *Service) QueryServiceConfigWithContext(ctx context.Context) (mgr.Config, error) {
+	return s.srv.Config()
+}
+
+// QueryStatus return the specified name service currentState and ControlsAccepted
+func (s *Service) QueryStatus() (ServiceStatus, error) {
+	return s.QueryStatusWithContext(context.Background())
+}
+
+// QueryStatusWithContext return the specified name service currentState and ControlsAccepted
+func (s *Service) QueryStatusWithContext(ctx context.Context) (ServiceStatus, error) {
+	var p *windows.SERVICE_STATUS_PROCESS
+	var bytesNeeded uint32
+	var buf []byte
+
+	if err := QueryServiceStatusEx(s.srv.Handle, SC_STATUS_PROCESS_INFO, nil, 0, &bytesNeeded); err != windows.ERROR_INSUFFICIENT_BUFFER {
+		return ServiceStatus{}, err
+	}
+
+	buf = make([]byte, bytesNeeded)
+	p = (*windows.SERVICE_STATUS_PROCESS)(unsafe.Pointer(&buf[0]))
+	if err := QueryServiceStatusEx(s.srv.Handle, SC_STATUS_PROCESS_INFO, &buf[0], uint32(len(buf)), &bytesNeeded); err != nil {
+		return ServiceStatus{}, err
+	}
+
+	return ServiceStatus{
+		State:         svc.State(p.CurrentState),
+		Accepts:       svc.Accepted(p.ControlsAccepted),
+		Pid:           p.ProcessId,
+		Win32ExitCode: p.Win32ExitCode,
+	}, nil
+}
+
+// ListServices return all windows service
+// reference to golang.org/x/sys/windows/svc/mgr#ListServices()
+func ListServices() ([]Service, error) {
+	m, err := openSCManager()
+	if err != nil {
+		return nil, err
+	}
+	defer m.close()
+
+	names, err := m.mgr.ListServices()
+	if err != nil {
+		return nil, err
+	}
+
+	services := make([]Service, 0)
+	for _, name := range names {
+		services = append(services, Service{Name: name})
+	}
+
+	return services, nil
+}

winservices/zsyscall_windows_ex.go

+// +build windows
+
+package winservices
+
+import (
+	"syscall"
+	"unsafe"
+
+	"golang.org/x/sys/windows"
+)
+
+var (
+	modadvapi32              = windows.NewLazySystemDLL("advapi32.dll")
+	procQueryServiceStatusEx = modadvapi32.NewProc("QueryServiceStatusEx")
+)
+
+// Do the interface allocations only once for common
+// Errno values.
+const (
+	errnoERROR_IO_PENDING = 997
+)
+
+var (
+	errERROR_IO_PENDING error = syscall.Errno(errnoERROR_IO_PENDING)
+)
+
+// errnoErr returns common boxed Errno values, to prevent
+// allocations at runtime.
+func errnoErr(e syscall.Errno) error {
+	switch e {
+	case 0:
+		return nil
+	case errnoERROR_IO_PENDING:
+		return errERROR_IO_PENDING
+	}
+	// TODO: add more here, after collecting data on the common
+	// error values see on Windows. (perhaps when running
+	// all.bat?)
+	return e
+}
+
+// SC_STATUS_PROCESS_INFO reference to https://msdn.microsoft.com/en-us/library/windows/desktop/ms684941(v=vs.85).aspx,
+// Use SC_STATUS_PROCESS_INFO to retrieve the service status information.
+const SC_STATUS_PROCESS_INFO int = 0
+
+// QueryServiceStatusEx golang/sys/windows standard library can not implement QueryServiceStatusEx.
+func QueryServiceStatusEx(service windows.Handle, infoLevel int, buff *byte, buffSize uint32, bytesNeeded *uint32) (err error) {
+	r1, _, e1 := syscall.Syscall6(procQueryServiceStatusEx.Addr(), 5, uintptr(service), uintptr(infoLevel), uintptr(unsafe.Pointer(buff)), uintptr(buffSize), uintptr(unsafe.Pointer(bytesNeeded)), 0)
+	if r1 == 0 {
+		if e1 != 0 {
+			err = errnoErr(e1)
+		} else {
+			err = syscall.EINVAL
+		}
+	}
+	return
+}