// Unwatch implements trigger.
func (k *kq) Unwatch(w *watched) (err error) {
var kevn [1]syscall.Kevent_t
syscall.SetKevent(&kevn[0], w.fd, syscall.EVFILT_VNODE, syscall.EV_DELETE)
_, err = syscall.Kevent(k.fd, kevn[:], nil, nil)
return
}
// watch starts to watch given p file/directory.
func (k *kqueue) singlewatch(p string, e Event, direct bool,
fi os.FileInfo) error {
w, ok := k.pthLkp[p]
if !ok {
fd, err := syscall.Open(p, syscall.O_NONBLOCK|syscall.O_RDONLY, 0)
if err != nil {
return err
}
w = &watched{fd: fd, p: p, fi: fi}
}
if direct {
w.eDir |= e
} else {
w.eNonDir |= e
}
var kevn [1]syscall.Kevent_t
syscall.SetKevent(&kevn[0], w.fd, syscall.EVFILT_VNODE,
syscall.EV_ADD|syscall.EV_CLEAR)
kevn[0].Fflags = encode(w.eDir | w.eNonDir)
if _, err := syscall.Kevent(k.fd, kevn[:], nil, nil); err != nil {
return err
}
if !ok {
k.idLkp[w.fd], k.pthLkp[w.p] = w, w
return nil
}
return errAlreadyWatched
}
func (this *watcher) doDel(path string) error {
info, found := this.watchedByPath[path]
if !found {
return errors.Newf("can't remove non-existent kevent watch for: %s", path)
}
var kbuf [1]syscall.Kevent_t
watchEntry := &kbuf[0]
syscall.SetKevent(watchEntry, info.fd, syscall.EVFILT_VNODE, syscall.EV_DELETE)
entryFlags := watchEntry.Flags
success, errno := syscall.Kevent(this.kq, kbuf[:], nil, nil)
if success == sysCallFailed {
return os.NewSyscallError("kevent_rm_watch", errno)
} else if entryFlags&syscall.EV_ERROR == syscall.EV_ERROR {
return errors.New("kevent rm error")
}
syscall.Close(info.fd)
//Remove childs if it's directory
for _, child := range info.childes {
this.doDel(child)
}
delete(this.watchedByPath, path)
delete(this.watchedByFD, info.fd)
return nil
}
func (p *pollster) WaitFD(s *pollServer, nsec int64) (fd int, mode int, err error) {
var t *syscall.Timespec
for len(p.events) == 0 {
if nsec > 0 {
if t == nil {
t = new(syscall.Timespec)
}
*t = syscall.NsecToTimespec(nsec)
}
s.Unlock()
n, err := syscall.Kevent(p.kq, nil, p.eventbuf[:], t)
s.Lock()
if err != nil {
if err == syscall.EINTR {
continue
}
return -1, 0, os.NewSyscallError("kevent", err)
}
if n == 0 {
return -1, 0, nil
}
p.events = p.eventbuf[:n]
}
ev := &p.events[0]
p.events = p.events[1:]
fd = int(ev.Ident)
if ev.Filter == syscall.EVFILT_READ {
mode = 'r'
} else {
mode = 'w'
}
return fd, mode, nil
}
func runKqueue() {
fd, err := syscall.Kqueue()
evTrackList := make([]syscall.Kevent_t, 1024)
if err != nil {
log.Fatal("error initializing Kqueue: ", err)
return
}
addFilesToKqueue(evTrackList, path)
// configure timeout
timeout := syscall.Timespec{
Sec: 0,
Nsec: 0,
}
// wait for events
for {
// create kevent
events := make([]syscall.Kevent_t, 10)
_, err := syscall.Kevent(fd, evTrackList, events, &timeout)
if err != nil {
log.Println("Error creating kevent")
}
// check if there was an event and process it
if len(events) > 0 && events[0].Ident > 0 {
processEvent()
}
}
}
func (p *pollster) Kevent(nsec int64) (result int, events []net_event, err error) {
var t *syscall.Timespec
if nsec > 0 {
if t == nil {
t = new(syscall.Timespec)
}
*t = syscall.NsecToTimespec(nsec)
}
n, err := syscall.Kevent(p.kq, nil, p.eventbuf[:], t)
if err != nil {
if err == syscall.EINTR {
return 0, nil, nil
} else {
return -1, nil, os.NewSyscallError("kevent", err)
}
}
if n == 0 {
return -2, nil, nil
}
events = make([]net_event, n)
for i, ev := range p.eventbuf {
events[i].fd = int(ev.Ident)
events[i].data = int(ev.Data)
if ev.Filter == syscall.EVFILT_READ {
events[i].mode = 'r'
} else {
events[i].mode = 'w'
}
}
return n, events, nil
}
// Poll the kqueue file descriptor and dispatch to the Event channels
func (w *Watcher) readEvents() {
listener, _ := w.listener.(*kqueueListener)
events := make([]syscall.Kevent_t, 10)
for {
if w.isDone() {
return
}
n, err := syscall.Kevent(listener.kq, nil, events, nil)
if err != nil {
w.Error <- err
continue
}
for _, ev := range events[:n] {
pid := int(ev.Ident)
switch ev.Fflags {
case syscall.NOTE_FORK:
w.Fork <- &ProcEventFork{ParentPid: pid}
case syscall.NOTE_EXEC:
w.Exec <- &ProcEventExec{Pid: pid}
case syscall.NOTE_EXIT:
w.RemoveWatch(pid)
w.Exit <- &ProcEventExit{Pid: pid}
}
}
}
}
func (p *pollster) WaitFD(nsec int64) (fd int, mode int, err os.Error) {
var t *syscall.Timespec
for len(p.events) == 0 {
if nsec > 0 {
if t == nil {
t = new(syscall.Timespec)
}
*t = syscall.NsecToTimespec(nsec)
}
nn, e := syscall.Kevent(p.kq, nil, &p.eventbuf, t)
if e != 0 {
if e == syscall.EINTR {
continue
}
return -1, 0, os.NewSyscallError("kevent", e)
}
if nn == 0 {
return -1, 0, nil
}
p.events = p.eventbuf[0:nn]
}
ev := &p.events[0]
p.events = p.events[1:len(p.events)]
fd = int(ev.Ident)
if ev.Filter == syscall.EVFILT_READ {
mode = 'r'
} else {
mode = 'w'
}
return fd, mode, nil
}
func (k *Kqueue) Wait(buf []syscall.Kevent_t) (int, error) {
n, err := syscall.Kevent(k.Fd, nil, buf, nil)
if err != nil {
return 0, os.NewSyscallError("kevent", err)
}
return n, nil
}
func (p *pollster) AddFD(fd int, mode int, repeat bool) os.Error {
var kmode int
if mode == 'r' {
kmode = syscall.EVFILT_READ
} else {
kmode = syscall.EVFILT_WRITE
}
var events [1]syscall.Kevent_t
ev := &events[0]
// EV_ADD - add event to kqueue list
// EV_RECEIPT - generate fake EV_ERROR as result of add,
// rather than waiting for real event
// EV_ONESHOT - delete the event the first time it triggers
flags := syscall.EV_ADD | syscall.EV_RECEIPT
if !repeat {
flags |= syscall.EV_ONESHOT
}
syscall.SetKevent(ev, fd, kmode, flags)
n, e := syscall.Kevent(p.kq, &events, &events, nil)
if e != 0 {
return os.NewSyscallError("kevent", e)
}
if n != 1 || (ev.Flags&syscall.EV_ERROR) == 0 || int(ev.Ident) != fd || int(ev.Filter) != kmode {
return os.ErrorString("kqueue phase error")
}
if ev.Data != 0 {
return os.Errno(int(ev.Data))
}
return nil
}
// read retrieves pending events, or waits until an event occurs.
// A timeout of nil blocks indefinitely, while 0 polls the queue.
func read(kq int, events []syscall.Kevent_t, timeout *syscall.Timespec) ([]syscall.Kevent_t, error) {
n, err := syscall.Kevent(kq, nil, events, timeout)
if err != nil {
return nil, err
}
return events[0:n], nil
}
// AddWatch adds path to the watched file set.
// The flags are interpreted as described in kevent(2).
func (w *Watcher) addWatch(path string, flags uint32) error {
if w.isClosed {
return errors.New("kevent instance already closed")
}
watchEntry := &w.kbuf[0]
watchEntry.Fflags = flags
watchfd, found := w.watches[path]
if !found {
fd, errno := syscall.Open(path, syscall.O_NONBLOCK|syscall.O_RDONLY, 0700)
if fd == -1 {
return &os.PathError{"kevent_add_watch", path, errno}
}
watchfd = fd
w.watches[path] = watchfd
w.paths[watchfd] = path
fi, _ := os.Stat(path)
w.finfo[watchfd] = &fi
}
syscall.SetKevent(watchEntry, watchfd, syscall.EVFILT_VNODE, syscall.EV_ADD|syscall.EV_CLEAR)
wd, errno := syscall.Kevent(w.kq, w.kbuf[:], nil, nil)
if wd == -1 {
return &os.PathError{"kevent_add_watch", path, errno}
} else if (watchEntry.Flags & syscall.EV_ERROR) == syscall.EV_ERROR {
return &os.PathError{"kevent_add_watch", path, errors.New(fmt.Sprintf("%v", watchEntry.Data))}
}
return nil
}
// unwatch stops watching p file/directory.
func (k *kqueue) singleunwatch(p string, direct bool) error {
w := k.pthLkp[p]
if w == nil {
return errNotWatched
}
if direct {
w.eDir = 0
} else {
w.eNonDir = 0
}
var kevn [1]syscall.Kevent_t
syscall.SetKevent(&kevn[0], w.fd, syscall.EVFILT_VNODE, syscall.EV_DELETE)
if _, err := syscall.Kevent(k.fd, kevn[:], nil, nil); err != nil {
return err
}
if w.eNonDir&w.eDir != 0 {
if err := k.singlewatch(p, w.eNonDir|w.eDir, w.eNonDir == 0,
w.fi); err != nil {
return err
}
} else {
k.del(*w)
}
return nil
}
// RemoveWatch removes path from the watched file set.
func (w *Watcher) removeWatch(path string) error {
w.wmut.Lock()
watchfd, ok := w.watches[path]
w.wmut.Unlock()
if !ok {
return errors.New(fmt.Sprintf("can't remove non-existent kevent watch for: %s", path))
}
w.bufmut.Lock()
defer w.bufmut.Unlock()
watchEntry := &w.kbuf[0]
syscall.SetKevent(watchEntry, watchfd, syscall.EVFILT_VNODE, syscall.EV_DELETE)
success, errno := syscall.Kevent(w.kq, w.kbuf[:], nil, nil)
if success == -1 {
return os.NewSyscallError("kevent_rm_watch", errno)
} else if (watchEntry.Flags & syscall.EV_ERROR) == syscall.EV_ERROR {
return errors.New("kevent rm error")
}
syscall.Close(watchfd)
w.wmut.Lock()
delete(w.watches, path)
w.wmut.Unlock()
w.enmut.Lock()
delete(w.enFlags, path)
w.enmut.Unlock()
w.pmut.Lock()
delete(w.paths, watchfd)
delete(w.finfo, watchfd)
w.pmut.Unlock()
return nil
}
// First return value is whether the pollServer should be woken up.
// This version always returns false.
func (p *pollster) AddFD(fd int, mode int, repeat bool) (bool, error) {
// pollServer is locked.
var kmode int
if mode == 'r' {
kmode = syscall.EVFILT_READ
} else {
kmode = syscall.EVFILT_WRITE
}
ev := &p.kbuf[0]
// EV_ADD - add event to kqueue list
// EV_ONESHOT - delete the event the first time it triggers
flags := syscall.EV_ADD
if !repeat {
flags |= syscall.EV_ONESHOT
}
syscall.SetKevent(ev, fd, kmode, flags)
n, err := syscall.Kevent(p.kq, p.kbuf[:], nil, nil)
if err != nil {
return false, os.NewSyscallError("kevent", err)
}
if n != 1 || (ev.Flags&syscall.EV_ERROR) == 0 || int(ev.Ident) != fd || int(ev.Filter) != kmode {
return false, os.NewSyscallError("kqueue phase error", err)
}
if ev.Data != 0 {
return false, syscall.Errno(int(ev.Data))
}
return false, nil
}
// Watch implements trigger.
func (k *kq) Watch(fi os.FileInfo, w *watched, e int64) (err error) {
var kevn [1]syscall.Kevent_t
syscall.SetKevent(&kevn[0], w.fd, syscall.EVFILT_VNODE,
syscall.EV_ADD|syscall.EV_CLEAR)
kevn[0].Fflags = uint32(e)
_, err = syscall.Kevent(k.fd, kevn[:], nil, nil)
return
}
// Remove stops watching the the named file or directory (non-recursively).
func (w *Watcher) Remove(name string) error {
name = filepath.Clean(name)
w.wmut.Lock()
watchfd, ok := w.watches[name]
w.wmut.Unlock()
if !ok {
return fmt.Errorf("can't remove non-existent kevent watch for: %s", name)
}
var kbuf [1]syscall.Kevent_t
watchEntry := &kbuf[0]
syscall.SetKevent(watchEntry, watchfd, syscall.EVFILT_VNODE, syscall.EV_DELETE)
entryFlags := watchEntry.Flags
success, errno := syscall.Kevent(w.kq, kbuf[:], nil, nil)
if success == -1 {
return os.NewSyscallError("kevent_rm_watch", errno)
} else if (entryFlags & syscall.EV_ERROR) == syscall.EV_ERROR {
return errors.New("kevent rm error")
}
syscall.Close(watchfd)
w.wmut.Lock()
delete(w.watches, name)
w.wmut.Unlock()
w.enmut.Lock()
delete(w.enFlags, name)
w.enmut.Unlock()
w.pmut.Lock()
delete(w.paths, watchfd)
fInfo := w.finfo[watchfd]
delete(w.finfo, watchfd)
w.pmut.Unlock()
// Find all watched paths that are in this directory that are not external.
if fInfo.IsDir() {
var pathsToRemove []string
w.pmut.Lock()
for _, wpath := range w.paths {
wdir, _ := filepath.Split(wpath)
if filepath.Clean(wdir) == filepath.Clean(name) {
w.ewmut.Lock()
if !w.externalWatches[wpath] {
pathsToRemove = append(pathsToRemove, wpath)
}
w.ewmut.Unlock()
}
}
w.pmut.Unlock()
for _, name := range pathsToRemove {
// Since these are internal, not much sense in propagating error
// to the user, as that will just confuse them with an error about
// a path they did not explicitly watch themselves.
w.Remove(name)
}
}
return nil
}
// Wait implements trigger.
func (k *kq) Wait() (interface{}, error) {
var (
kevn [1]syscall.Kevent_t
err error
)
kevn[0] = syscall.Kevent_t{}
_, err = syscall.Kevent(k.fd, nil, kevn[:], nil)
return kevn[0], err
}
// RemoveWatch removes path from the watched file set.
func (w *Watcher) removeWatch(path string) error {
w.wmut.Lock()
watchfd, ok := w.watches[path]
w.wmut.Unlock()
if !ok {
return errors.New(fmt.Sprintf("can't remove non-existent kevent watch for: %s", path))
}
w.bufmut.Lock()
watchEntry := &w.kbuf[0]
syscall.SetKevent(watchEntry, watchfd, syscall.EVFILT_VNODE, syscall.EV_DELETE)
success, errno := syscall.Kevent(w.kq, w.kbuf[:], nil, nil)
w.bufmut.Unlock()
if success == -1 {
return os.NewSyscallError("kevent_rm_watch", errno)
} else if (watchEntry.Flags & syscall.EV_ERROR) == syscall.EV_ERROR {
return errors.New("kevent rm error")
}
syscall.Close(watchfd)
w.wmut.Lock()
delete(w.watches, path)
w.wmut.Unlock()
w.enmut.Lock()
delete(w.enFlags, path)
w.enmut.Unlock()
w.pmut.Lock()
delete(w.paths, watchfd)
fInfo := w.finfo[watchfd]
delete(w.finfo, watchfd)
w.pmut.Unlock()
// Find all watched paths that are in this directory that are not external.
if fInfo.IsDir() {
pathsToRemove := make([]string, 0)
w.pmut.Lock()
for _, wpath := range w.paths {
wdir, _ := filepath.Split(wpath)
if filepath.Clean(wdir) == filepath.Clean(path) {
w.ewmut.Lock()
if _, extern := w.externalWatches[wpath]; !extern {
pathsToRemove = append(pathsToRemove, wpath)
}
w.ewmut.Unlock()
}
}
w.pmut.Unlock()
for idx := 0; idx < len(pathsToRemove); idx++ {
// Since these are internal, not much sense in propogating error
// to the user, as that will just confuse them with an error about
// a path they did not explicitly watch themselves.
w.removeWatch(pathsToRemove[idx])
}
}
return nil
}
func (k *Kqueue) Add(fd uintptr, filter, flags int, fflags uint32) error {
var buf [1]syscall.Kevent_t
ev := &buf[0]
flags = flags | syscall.EV_ADD
evset(ev, fd, filter, flags, fflags)
_, err := syscall.Kevent(k.Fd, buf[:], nil, nil)
if err != nil {
return os.NewSyscallError("kevent", err)
}
return nil
}
// Initialize Kevent_t fields and propagate changelist for the given pid
func (w *Watcher) kevent(pid int, fflags uint32, flags int) error {
listener, _ := w.listener.(*kqueueListener)
event := &listener.buf[0]
syscall.SetKevent(event, pid, syscall.EVFILT_PROC, flags)
event.Fflags = fflags
_, err := syscall.Kevent(listener.kq, listener.buf[:], nil, nil)
return err
}
func (p *pollster) DelFD(fd int, mode int) {
var kmode int
if mode == 'r' {
kmode = syscall.EVFILT_READ
} else {
kmode = syscall.EVFILT_WRITE
}
var events [1]syscall.Kevent_t
ev := &events[0]
// EV_DELETE - delete event from kqueue list
syscall.SetKevent(ev, fd, kmode, syscall.EV_DELETE)
syscall.Kevent(p.kq, &events, nil, nil)
}
// init initializes kqueue.
func (k *kqueue) init() (err error) {
if k.fd, err = syscall.Kqueue(); err != nil {
return
}
// Creates pipe used to stop `Kevent` call by registering it,
// watching read end and writing to other end of it.
if err = syscall.Pipe(k.pipefds[:]); err != nil {
return
}
var kevn [1]syscall.Kevent_t
syscall.SetKevent(&kevn[0], k.pipefds[0], syscall.EVFILT_READ, syscall.EV_ADD)
_, err = syscall.Kevent(k.fd, kevn[:], nil, nil)
return
}
func (p *pollster) DelFD(fd int, mode int) {
// pollServer is locked.
var kmode int
if mode == 'r' {
kmode = syscall.EVFILT_READ
} else {
kmode = syscall.EVFILT_WRITE
}
ev := &p.kbuf[0]
// EV_DELETE - delete event from kqueue list
syscall.SetKevent(ev, fd, kmode, syscall.EV_DELETE)
syscall.Kevent(p.kq, p.kbuf[:], nil, nil)
}
func (p *pollster) DelFD(fd int, mode int) {
var kmode int
if mode == 'r' {
kmode = syscall.EVFILT_READ
} else {
kmode = syscall.EVFILT_WRITE
}
var events [1]syscall.Kevent_t
ev := &events[0]
// EV_DELETE - delete event from kqueue list
// EV_RECEIPT - generate fake EV_ERROR as result of add,
// rather than waiting for real event
syscall.SetKevent(ev, fd, kmode, syscall.EV_DELETE|syscall.EV_RECEIPT)
syscall.Kevent(p.kq, &events, &events, nil)
}
func (p *pollster) DelFD(fd int, mode int) {
// pollServer is locked.
var kmode int
if mode == 'r' {
kmode = syscall.EVFILT_READ
} else {
kmode = syscall.EVFILT_WRITE
}
ev := &p.kbuf[0]
// EV_DELETE - delete event from kqueue list
// EV_RECEIPT - generate fake EV_ERROR as result of add,
// rather than waiting for real event
syscall.SetKevent(ev, fd, kmode, syscall.EV_DELETE|syscall.EV_RECEIPT)
syscall.Kevent(p.kq, p.kbuf[0:], p.kbuf[0:], nil)
}
// register events with the queue
func register(kq int, fds []int, flags int, fflags uint32) error {
changes := make([]syscall.Kevent_t, len(fds))
for i, fd := range fds {
// SetKevent converts int to the platform-specific types:
syscall.SetKevent(&changes[i], fd, syscall.EVFILT_VNODE, flags)
changes[i].Fflags = fflags
}
// register the events
success, err := syscall.Kevent(kq, changes, nil, nil)
if success == -1 {
return err
}
return nil
}
func (k *kqueue) add(fd uintptr, filter, flags int, fflags uint32) error {
var buf [1]syscall.Kevent_t
ev := &buf[0]
flags = flags | syscall.EV_ADD | syscall.EV_RECEIPT
evset(ev, fd, filter, flags, fflags)
n, err := syscall.Kevent(k.fd, buf[:], buf[:], nil)
if err != nil {
return os.NewSyscallError("kevent", err)
}
if n != 1 || (ev.Flags&syscall.EV_ERROR) == 0 || uintptr(ev.Ident) != fd || int(ev.Filter) != filter {
return errors.New("kqueue phase error")
}
if ev.Data != 0 {
return syscall.Errno(ev.Data)
}
return nil
}
// RemoveWatch removes path from the watched file set.
func (w *Watcher) RemoveWatch(path string) error {
watchfd, ok := w.watches[path]
if !ok {
return errors.New(fmt.Sprintf("can't remove non-existent kevent watch for: %s", path))
}
syscall.Close(watchfd)
watchEntry := &w.kbuf[0]
syscall.SetKevent(watchEntry, w.watches[path], syscall.EVFILT_VNODE, syscall.EV_DELETE)
success, errno := syscall.Kevent(w.kq, w.kbuf[:], nil, nil)
if success == -1 {
return os.NewSyscallError("kevent_rm_watch", errno)
} else if (watchEntry.Flags & syscall.EV_ERROR) == syscall.EV_ERROR {
return os.NewSyscallError("kevent_rm_watch", errors.New(fmt.Sprintf("%v", watchEntry.Data)))
}
delete(w.watches, path)
return nil
}
// monitor reads reported kqueue events and forwards them further after
// performing additional processing. If read event concerns directory,
// it generates Create/Remove event and sent them further instead of directory
// event. This event is detected based on reading contents of analyzed
// directory. If no changes in file list are detected, no event is send further.
// Reading directory structure is less accurate than kqueue and can lead
// to lack of detection of all events.
func (k *kqueue) monitor() {
var (
kevn [1]syscall.Kevent_t
n int
err error
)
for {
kevn[0] = syscall.Kevent_t{}
switch n, err = syscall.Kevent(k.fd, nil, kevn[:], nil); {
case err == syscall.EINTR:
case err != nil:
dbgprintf("kqueue: failed to read events: %q\n", err)
case int(kevn[0].Ident) == k.pipefds[0]:
k.s <- struct{}{}
return
case n > 0:
k.sendEvents(k.process(kevn[0]))
}
}
}
