diff options
Diffstat (limited to 'vendor/gopkg.in/fsnotify.v1/inotify.go')
-rw-r--r-- | vendor/gopkg.in/fsnotify.v1/inotify.go | 337 |
1 files changed, 0 insertions, 337 deletions
diff --git a/vendor/gopkg.in/fsnotify.v1/inotify.go b/vendor/gopkg.in/fsnotify.v1/inotify.go deleted file mode 100644 index d9fd1b88a..000000000 --- a/vendor/gopkg.in/fsnotify.v1/inotify.go +++ /dev/null @@ -1,337 +0,0 @@ -// 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 linux - -package fsnotify - -import ( - "errors" - "fmt" - "io" - "os" - "path/filepath" - "strings" - "sync" - "unsafe" - - "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 - mu sync.Mutex // Map access - fd int - poller *fdPoller - watches map[string]*watch // Map of inotify watches (key: path) - paths map[int]string // Map of watched paths (key: watch descriptor) - done chan struct{} // Channel for sending a "quit message" to the reader goroutine - doneResp chan struct{} // Channel to respond to Close -} - -// NewWatcher establishes a new watcher with the underlying OS and begins waiting for events. -func NewWatcher() (*Watcher, error) { - // Create inotify fd - fd, errno := unix.InotifyInit1(unix.IN_CLOEXEC) - if fd == -1 { - return nil, errno - } - // Create epoll - poller, err := newFdPoller(fd) - if err != nil { - unix.Close(fd) - return nil, err - } - w := &Watcher{ - fd: fd, - poller: poller, - watches: make(map[string]*watch), - paths: make(map[int]string), - Events: make(chan Event), - Errors: make(chan error), - done: make(chan struct{}), - doneResp: make(chan struct{}), - } - - go w.readEvents() - return w, nil -} - -func (w *Watcher) isClosed() bool { - select { - case <-w.done: - return true - default: - return false - } -} - -// Close removes all watches and closes the events channel. -func (w *Watcher) Close() error { - if w.isClosed() { - return nil - } - - // Send 'close' signal to goroutine, and set the Watcher to closed. - close(w.done) - - // Wake up goroutine - w.poller.wake() - - // Wait for goroutine to close - <-w.doneResp - - return nil -} - -// Add starts watching the named file or directory (non-recursively). -func (w *Watcher) Add(name string) error { - name = filepath.Clean(name) - if w.isClosed() { - return errors.New("inotify instance already closed") - } - - const agnosticEvents = unix.IN_MOVED_TO | unix.IN_MOVED_FROM | - unix.IN_CREATE | unix.IN_ATTRIB | unix.IN_MODIFY | - unix.IN_MOVE_SELF | unix.IN_DELETE | unix.IN_DELETE_SELF - - var flags uint32 = agnosticEvents - - w.mu.Lock() - defer w.mu.Unlock() - watchEntry := w.watches[name] - if watchEntry != nil { - flags |= watchEntry.flags | unix.IN_MASK_ADD - } - wd, errno := unix.InotifyAddWatch(w.fd, name, flags) - if wd == -1 { - return errno - } - - if watchEntry == nil { - w.watches[name] = &watch{wd: uint32(wd), flags: flags} - w.paths[wd] = name - } else { - watchEntry.wd = uint32(wd) - watchEntry.flags = flags - } - - return nil -} - -// Remove stops watching the named file or directory (non-recursively). -func (w *Watcher) Remove(name string) error { - name = filepath.Clean(name) - - // Fetch the watch. - w.mu.Lock() - defer w.mu.Unlock() - watch, ok := w.watches[name] - - // Remove it from inotify. - if !ok { - return fmt.Errorf("can't remove non-existent inotify watch for: %s", name) - } - - // We successfully removed the watch if InotifyRmWatch doesn't return an - // error, we need to clean up our internal state to ensure it matches - // inotify's kernel state. - delete(w.paths, int(watch.wd)) - delete(w.watches, name) - - // inotify_rm_watch will return EINVAL if the file has been deleted; - // the inotify will already have been removed. - // watches and pathes are deleted in ignoreLinux() implicitly and asynchronously - // by calling inotify_rm_watch() below. e.g. readEvents() goroutine receives IN_IGNORE - // so that EINVAL means that the wd is being rm_watch()ed or its file removed - // by another thread and we have not received IN_IGNORE event. - success, errno := unix.InotifyRmWatch(w.fd, watch.wd) - if success == -1 { - // TODO: Perhaps it's not helpful to return an error here in every case. - // the only two possible errors are: - // EBADF, which happens when w.fd is not a valid file descriptor of any kind. - // EINVAL, which is when fd is not an inotify descriptor or wd is not a valid watch descriptor. - // Watch descriptors are invalidated when they are removed explicitly or implicitly; - // explicitly by inotify_rm_watch, implicitly when the file they are watching is deleted. - return errno - } - - return nil -} - -type watch struct { - wd uint32 // Watch descriptor (as returned by the inotify_add_watch() syscall) - flags uint32 // inotify flags of this watch (see inotify(7) for the list of valid flags) -} - -// readEvents reads from the inotify file descriptor, converts the -// received events into Event objects and sends them via the Events channel -func (w *Watcher) readEvents() { - var ( - buf [unix.SizeofInotifyEvent * 4096]byte // Buffer for a maximum of 4096 raw events - n int // Number of bytes read with read() - errno error // Syscall errno - ok bool // For poller.wait - ) - - defer close(w.doneResp) - defer close(w.Errors) - defer close(w.Events) - defer unix.Close(w.fd) - defer w.poller.close() - - for { - // See if we have been closed. - if w.isClosed() { - return - } - - ok, errno = w.poller.wait() - if errno != nil { - select { - case w.Errors <- errno: - case <-w.done: - return - } - continue - } - - if !ok { - continue - } - - n, errno = unix.Read(w.fd, buf[:]) - // If a signal interrupted execution, see if we've been asked to close, and try again. - // http://man7.org/linux/man-pages/man7/signal.7.html : - // "Before Linux 3.8, reads from an inotify(7) file descriptor were not restartable" - if errno == unix.EINTR { - continue - } - - // unix.Read might have been woken up by Close. If so, we're done. - if w.isClosed() { - return - } - - if n < unix.SizeofInotifyEvent { - var err error - if n == 0 { - // If EOF is received. This should really never happen. - err = io.EOF - } else if n < 0 { - // If an error occurred while reading. - err = errno - } else { - // Read was too short. - err = errors.New("notify: short read in readEvents()") - } - select { - case w.Errors <- err: - case <-w.done: - return - } - continue - } - - var offset uint32 - // We don't know how many events we just read into the buffer - // While the offset points to at least one whole event... - for offset <= uint32(n-unix.SizeofInotifyEvent) { - // Point "raw" to the event in the buffer - raw := (*unix.InotifyEvent)(unsafe.Pointer(&buf[offset])) - - mask := uint32(raw.Mask) - nameLen := uint32(raw.Len) - - if mask&unix.IN_Q_OVERFLOW != 0 { - select { - case w.Errors <- ErrEventOverflow: - case <-w.done: - return - } - } - - // If the event happened to the watched directory or the watched file, the kernel - // doesn't append the filename to the event, but we would like to always fill the - // the "Name" field with a valid filename. We retrieve the path of the watch from - // the "paths" map. - w.mu.Lock() - name, ok := w.paths[int(raw.Wd)] - // IN_DELETE_SELF occurs when the file/directory being watched is removed. - // This is a sign to clean up the maps, otherwise we are no longer in sync - // with the inotify kernel state which has already deleted the watch - // automatically. - if ok && mask&unix.IN_DELETE_SELF == unix.IN_DELETE_SELF { - delete(w.paths, int(raw.Wd)) - delete(w.watches, name) - } - w.mu.Unlock() - - if nameLen > 0 { - // Point "bytes" at the first byte of the filename - bytes := (*[unix.PathMax]byte)(unsafe.Pointer(&buf[offset+unix.SizeofInotifyEvent])) - // The filename is padded with NULL bytes. TrimRight() gets rid of those. - name += "/" + strings.TrimRight(string(bytes[0:nameLen]), "\000") - } - - event := newEvent(name, mask) - - // Send the events that are not ignored on the events channel - if !event.ignoreLinux(mask) { - select { - case w.Events <- event: - case <-w.done: - return - } - } - - // Move to the next event in the buffer - offset += unix.SizeofInotifyEvent + nameLen - } - } -} - -// Certain types of events can be "ignored" and not sent over the Events -// channel. Such as events marked ignore by the kernel, or MODIFY events -// against files that do not exist. -func (e *Event) ignoreLinux(mask uint32) bool { - // Ignore anything the inotify API says to ignore - if mask&unix.IN_IGNORED == unix.IN_IGNORED { - return true - } - - // If the event is not a DELETE or RENAME, the file must exist. - // Otherwise the event is ignored. - // *Note*: this was put in place because it was seen that a MODIFY - // event was sent after the DELETE. This ignores that MODIFY and - // assumes a DELETE will come or has come if the file doesn't exist. - if !(e.Op&Remove == Remove || e.Op&Rename == Rename) { - _, statErr := os.Lstat(e.Name) - return os.IsNotExist(statErr) - } - return false -} - -// newEvent returns an platform-independent Event based on an inotify mask. -func newEvent(name string, mask uint32) Event { - e := Event{Name: name} - if mask&unix.IN_CREATE == unix.IN_CREATE || mask&unix.IN_MOVED_TO == unix.IN_MOVED_TO { - e.Op |= Create - } - if mask&unix.IN_DELETE_SELF == unix.IN_DELETE_SELF || mask&unix.IN_DELETE == unix.IN_DELETE { - e.Op |= Remove - } - if mask&unix.IN_MODIFY == unix.IN_MODIFY { - e.Op |= Write - } - if mask&unix.IN_MOVE_SELF == unix.IN_MOVE_SELF || mask&unix.IN_MOVED_FROM == unix.IN_MOVED_FROM { - e.Op |= Rename - } - if mask&unix.IN_ATTRIB == unix.IN_ATTRIB { - e.Op |= Chmod - } - return e -} |