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-rw-r--r--vendor/github.com/fsnotify/fsnotify/kqueue.go521
1 files changed, 521 insertions, 0 deletions
diff --git a/vendor/github.com/fsnotify/fsnotify/kqueue.go b/vendor/github.com/fsnotify/fsnotify/kqueue.go
new file mode 100644
index 00000000..86e76a3d
--- /dev/null
+++ b/vendor/github.com/fsnotify/fsnotify/kqueue.go
@@ -0,0 +1,521 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build freebsd openbsd netbsd dragonfly darwin
+
+package fsnotify
+
+import (
+ "errors"
+ "fmt"
+ "io/ioutil"
+ "os"
+ "path/filepath"
+ "sync"
+ "time"
+
+ "golang.org/x/sys/unix"
+)
+
+// Watcher watches a set of files, delivering events to a channel.
+type Watcher struct {
+ Events chan Event
+ Errors chan error
+ done chan struct{} // Channel for sending a "quit message" to the reader goroutine
+
+ kq int // File descriptor (as returned by the kqueue() syscall).
+
+ mu sync.Mutex // Protects access to watcher data
+ watches map[string]int // Map of watched file descriptors (key: path).
+ externalWatches map[string]bool // Map of watches added by user of the library.
+ dirFlags map[string]uint32 // Map of watched directories to fflags used in kqueue.
+ paths map[int]pathInfo // Map file descriptors to path names for processing kqueue events.
+ fileExists map[string]bool // Keep track of if we know this file exists (to stop duplicate create events).
+ isClosed bool // Set to true when Close() is first called
+}
+
+type pathInfo struct {
+ name string
+ isDir bool
+}
+
+// NewWatcher establishes a new watcher with the underlying OS and begins waiting for events.
+func NewWatcher() (*Watcher, error) {
+ kq, err := kqueue()
+ if err != nil {
+ return nil, err
+ }
+
+ w := &Watcher{
+ kq: kq,
+ watches: make(map[string]int),
+ dirFlags: make(map[string]uint32),
+ paths: make(map[int]pathInfo),
+ fileExists: make(map[string]bool),
+ externalWatches: make(map[string]bool),
+ Events: make(chan Event),
+ Errors: make(chan error),
+ done: make(chan struct{}),
+ }
+
+ go w.readEvents()
+ return w, nil
+}
+
+// Close removes all watches and closes the events channel.
+func (w *Watcher) Close() error {
+ w.mu.Lock()
+ if w.isClosed {
+ w.mu.Unlock()
+ return nil
+ }
+ w.isClosed = true
+
+ // copy paths to remove while locked
+ var pathsToRemove = make([]string, 0, len(w.watches))
+ for name := range w.watches {
+ pathsToRemove = append(pathsToRemove, name)
+ }
+ w.mu.Unlock()
+ // unlock before calling Remove, which also locks
+
+ for _, name := range pathsToRemove {
+ w.Remove(name)
+ }
+
+ // send a "quit" message to the reader goroutine
+ close(w.done)
+
+ return nil
+}
+
+// Add starts watching the named file or directory (non-recursively).
+func (w *Watcher) Add(name string) error {
+ w.mu.Lock()
+ w.externalWatches[name] = true
+ w.mu.Unlock()
+ _, err := w.addWatch(name, noteAllEvents)
+ return err
+}
+
+// Remove stops watching the the named file or directory (non-recursively).
+func (w *Watcher) Remove(name string) error {
+ name = filepath.Clean(name)
+ w.mu.Lock()
+ watchfd, ok := w.watches[name]
+ w.mu.Unlock()
+ if !ok {
+ return fmt.Errorf("can't remove non-existent kevent watch for: %s", name)
+ }
+
+ const registerRemove = unix.EV_DELETE
+ if err := register(w.kq, []int{watchfd}, registerRemove, 0); err != nil {
+ return err
+ }
+
+ unix.Close(watchfd)
+
+ w.mu.Lock()
+ isDir := w.paths[watchfd].isDir
+ delete(w.watches, name)
+ delete(w.paths, watchfd)
+ delete(w.dirFlags, name)
+ w.mu.Unlock()
+
+ // Find all watched paths that are in this directory that are not external.
+ if isDir {
+ var pathsToRemove []string
+ w.mu.Lock()
+ for _, path := range w.paths {
+ wdir, _ := filepath.Split(path.name)
+ if filepath.Clean(wdir) == name {
+ if !w.externalWatches[path.name] {
+ pathsToRemove = append(pathsToRemove, path.name)
+ }
+ }
+ }
+ w.mu.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
+}
+
+// Watch all events (except NOTE_EXTEND, NOTE_LINK, NOTE_REVOKE)
+const noteAllEvents = unix.NOTE_DELETE | unix.NOTE_WRITE | unix.NOTE_ATTRIB | unix.NOTE_RENAME
+
+// keventWaitTime to block on each read from kevent
+var keventWaitTime = durationToTimespec(100 * time.Millisecond)
+
+// addWatch adds name to the watched file set.
+// The flags are interpreted as described in kevent(2).
+// Returns the real path to the file which was added, if any, which may be different from the one passed in the case of symlinks.
+func (w *Watcher) addWatch(name string, flags uint32) (string, error) {
+ var isDir bool
+ // Make ./name and name equivalent
+ name = filepath.Clean(name)
+
+ w.mu.Lock()
+ if w.isClosed {
+ w.mu.Unlock()
+ return "", errors.New("kevent instance already closed")
+ }
+ watchfd, alreadyWatching := w.watches[name]
+ // We already have a watch, but we can still override flags.
+ if alreadyWatching {
+ isDir = w.paths[watchfd].isDir
+ }
+ w.mu.Unlock()
+
+ if !alreadyWatching {
+ fi, err := os.Lstat(name)
+ if err != nil {
+ return "", err
+ }
+
+ // Don't watch sockets.
+ if fi.Mode()&os.ModeSocket == os.ModeSocket {
+ return "", nil
+ }
+
+ // Don't watch named pipes.
+ if fi.Mode()&os.ModeNamedPipe == os.ModeNamedPipe {
+ return "", nil
+ }
+
+ // Follow Symlinks
+ // Unfortunately, Linux can add bogus symlinks to watch list without
+ // issue, and Windows can't do symlinks period (AFAIK). To maintain
+ // consistency, we will act like everything is fine. There will simply
+ // be no file events for broken symlinks.
+ // Hence the returns of nil on errors.
+ if fi.Mode()&os.ModeSymlink == os.ModeSymlink {
+ name, err = filepath.EvalSymlinks(name)
+ if err != nil {
+ return "", nil
+ }
+
+ w.mu.Lock()
+ _, alreadyWatching = w.watches[name]
+ w.mu.Unlock()
+
+ if alreadyWatching {
+ return name, nil
+ }
+
+ fi, err = os.Lstat(name)
+ if err != nil {
+ return "", nil
+ }
+ }
+
+ watchfd, err = unix.Open(name, openMode, 0700)
+ if watchfd == -1 {
+ return "", err
+ }
+
+ isDir = fi.IsDir()
+ }
+
+ const registerAdd = unix.EV_ADD | unix.EV_CLEAR | unix.EV_ENABLE
+ if err := register(w.kq, []int{watchfd}, registerAdd, flags); err != nil {
+ unix.Close(watchfd)
+ return "", err
+ }
+
+ if !alreadyWatching {
+ w.mu.Lock()
+ w.watches[name] = watchfd
+ w.paths[watchfd] = pathInfo{name: name, isDir: isDir}
+ w.mu.Unlock()
+ }
+
+ if isDir {
+ // Watch the directory if it has not been watched before,
+ // or if it was watched before, but perhaps only a NOTE_DELETE (watchDirectoryFiles)
+ w.mu.Lock()
+
+ watchDir := (flags&unix.NOTE_WRITE) == unix.NOTE_WRITE &&
+ (!alreadyWatching || (w.dirFlags[name]&unix.NOTE_WRITE) != unix.NOTE_WRITE)
+ // Store flags so this watch can be updated later
+ w.dirFlags[name] = flags
+ w.mu.Unlock()
+
+ if watchDir {
+ if err := w.watchDirectoryFiles(name); err != nil {
+ return "", err
+ }
+ }
+ }
+ return name, nil
+}
+
+// readEvents reads from kqueue and converts the received kevents into
+// Event values that it sends down the Events channel.
+func (w *Watcher) readEvents() {
+ eventBuffer := make([]unix.Kevent_t, 10)
+
+loop:
+ for {
+ // See if there is a message on the "done" channel
+ select {
+ case <-w.done:
+ break loop
+ default:
+ }
+
+ // Get new events
+ kevents, err := read(w.kq, eventBuffer, &keventWaitTime)
+ // EINTR is okay, the syscall was interrupted before timeout expired.
+ if err != nil && err != unix.EINTR {
+ select {
+ case w.Errors <- err:
+ case <-w.done:
+ break loop
+ }
+ continue
+ }
+
+ // Flush the events we received to the Events channel
+ for len(kevents) > 0 {
+ kevent := &kevents[0]
+ watchfd := int(kevent.Ident)
+ mask := uint32(kevent.Fflags)
+ w.mu.Lock()
+ path := w.paths[watchfd]
+ w.mu.Unlock()
+ event := newEvent(path.name, mask)
+
+ if path.isDir && !(event.Op&Remove == Remove) {
+ // Double check to make sure the directory exists. This can happen when
+ // we do a rm -fr on a recursively watched folders and we receive a
+ // modification event first but the folder has been deleted and later
+ // receive the delete event
+ if _, err := os.Lstat(event.Name); os.IsNotExist(err) {
+ // mark is as delete event
+ event.Op |= Remove
+ }
+ }
+
+ if event.Op&Rename == Rename || event.Op&Remove == Remove {
+ w.Remove(event.Name)
+ w.mu.Lock()
+ delete(w.fileExists, event.Name)
+ w.mu.Unlock()
+ }
+
+ if path.isDir && event.Op&Write == Write && !(event.Op&Remove == Remove) {
+ w.sendDirectoryChangeEvents(event.Name)
+ } else {
+ // Send the event on the Events channel.
+ select {
+ case w.Events <- event:
+ case <-w.done:
+ break loop
+ }
+ }
+
+ if event.Op&Remove == Remove {
+ // Look for a file that may have overwritten this.
+ // For example, mv f1 f2 will delete f2, then create f2.
+ if path.isDir {
+ fileDir := filepath.Clean(event.Name)
+ w.mu.Lock()
+ _, found := w.watches[fileDir]
+ w.mu.Unlock()
+ if found {
+ // make sure the directory exists before we watch for changes. When we
+ // do a recursive watch and perform rm -fr, the parent directory might
+ // have gone missing, ignore the missing directory and let the
+ // upcoming delete event remove the watch from the parent directory.
+ if _, err := os.Lstat(fileDir); err == nil {
+ w.sendDirectoryChangeEvents(fileDir)
+ }
+ }
+ } else {
+ filePath := filepath.Clean(event.Name)
+ if fileInfo, err := os.Lstat(filePath); err == nil {
+ w.sendFileCreatedEventIfNew(filePath, fileInfo)
+ }
+ }
+ }
+
+ // Move to next event
+ kevents = kevents[1:]
+ }
+ }
+
+ // cleanup
+ err := unix.Close(w.kq)
+ if err != nil {
+ // only way the previous loop breaks is if w.done was closed so we need to async send to w.Errors.
+ select {
+ case w.Errors <- err:
+ default:
+ }
+ }
+ close(w.Events)
+ close(w.Errors)
+}
+
+// newEvent returns an platform-independent Event based on kqueue Fflags.
+func newEvent(name string, mask uint32) Event {
+ e := Event{Name: name}
+ if mask&unix.NOTE_DELETE == unix.NOTE_DELETE {
+ e.Op |= Remove
+ }
+ if mask&unix.NOTE_WRITE == unix.NOTE_WRITE {
+ e.Op |= Write
+ }
+ if mask&unix.NOTE_RENAME == unix.NOTE_RENAME {
+ e.Op |= Rename
+ }
+ if mask&unix.NOTE_ATTRIB == unix.NOTE_ATTRIB {
+ e.Op |= Chmod
+ }
+ return e
+}
+
+func newCreateEvent(name string) Event {
+ return Event{Name: name, Op: Create}
+}
+
+// watchDirectoryFiles to mimic inotify when adding a watch on a directory
+func (w *Watcher) watchDirectoryFiles(dirPath string) error {
+ // Get all files
+ files, err := ioutil.ReadDir(dirPath)
+ if err != nil {
+ return err
+ }
+
+ for _, fileInfo := range files {
+ filePath := filepath.Join(dirPath, fileInfo.Name())
+ filePath, err = w.internalWatch(filePath, fileInfo)
+ if err != nil {
+ return err
+ }
+
+ w.mu.Lock()
+ w.fileExists[filePath] = true
+ w.mu.Unlock()
+ }
+
+ return nil
+}
+
+// sendDirectoryEvents searches the directory for newly created files
+// and sends them over the event channel. This functionality is to have
+// the BSD version of fsnotify match Linux inotify which provides a
+// create event for files created in a watched directory.
+func (w *Watcher) sendDirectoryChangeEvents(dirPath string) {
+ // Get all files
+ files, err := ioutil.ReadDir(dirPath)
+ if err != nil {
+ select {
+ case w.Errors <- err:
+ case <-w.done:
+ return
+ }
+ }
+
+ // Search for new files
+ for _, fileInfo := range files {
+ filePath := filepath.Join(dirPath, fileInfo.Name())
+ err := w.sendFileCreatedEventIfNew(filePath, fileInfo)
+
+ if err != nil {
+ return
+ }
+ }
+}
+
+// sendFileCreatedEvent sends a create event if the file isn't already being tracked.
+func (w *Watcher) sendFileCreatedEventIfNew(filePath string, fileInfo os.FileInfo) (err error) {
+ w.mu.Lock()
+ _, doesExist := w.fileExists[filePath]
+ w.mu.Unlock()
+ if !doesExist {
+ // Send create event
+ select {
+ case w.Events <- newCreateEvent(filePath):
+ case <-w.done:
+ return
+ }
+ }
+
+ // like watchDirectoryFiles (but without doing another ReadDir)
+ filePath, err = w.internalWatch(filePath, fileInfo)
+ if err != nil {
+ return err
+ }
+
+ w.mu.Lock()
+ w.fileExists[filePath] = true
+ w.mu.Unlock()
+
+ return nil
+}
+
+func (w *Watcher) internalWatch(name string, fileInfo os.FileInfo) (string, error) {
+ if fileInfo.IsDir() {
+ // mimic Linux providing delete events for subdirectories
+ // but preserve the flags used if currently watching subdirectory
+ w.mu.Lock()
+ flags := w.dirFlags[name]
+ w.mu.Unlock()
+
+ flags |= unix.NOTE_DELETE | unix.NOTE_RENAME
+ return w.addWatch(name, flags)
+ }
+
+ // watch file to mimic Linux inotify
+ return w.addWatch(name, noteAllEvents)
+}
+
+// kqueue creates a new kernel event queue and returns a descriptor.
+func kqueue() (kq int, err error) {
+ kq, err = unix.Kqueue()
+ if kq == -1 {
+ return kq, err
+ }
+ return kq, nil
+}
+
+// register events with the queue
+func register(kq int, fds []int, flags int, fflags uint32) error {
+ changes := make([]unix.Kevent_t, len(fds))
+
+ for i, fd := range fds {
+ // SetKevent converts int to the platform-specific types:
+ unix.SetKevent(&changes[i], fd, unix.EVFILT_VNODE, flags)
+ changes[i].Fflags = fflags
+ }
+
+ // register the events
+ success, err := unix.Kevent(kq, changes, nil, nil)
+ if success == -1 {
+ return err
+ }
+ 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 []unix.Kevent_t, timeout *unix.Timespec) ([]unix.Kevent_t, error) {
+ n, err := unix.Kevent(kq, nil, events, timeout)
+ if err != nil {
+ return nil, err
+ }
+ return events[0:n], nil
+}
+
+// durationToTimespec prepares a timeout value
+func durationToTimespec(d time.Duration) unix.Timespec {
+ return unix.NsecToTimespec(d.Nanoseconds())
+}