replace zxq.co/ripple/hanayo

vendor/github.com/rjeczalik/notify/watcher.go

@@ -0,0 +1,85 @@
+// Copyright (c) 2014-2015 The Notify Authors. All rights reserved.
+// Use of this source code is governed by the MIT license that can be
+// found in the LICENSE file.
+
+package notify
+
+import "errors"
+
+var (
+	errAlreadyWatched  = errors.New("path is already watched")
+	errNotWatched      = errors.New("path is not being watched")
+	errInvalidEventSet = errors.New("invalid event set provided")
+)
+
+// Watcher is a intermediate interface for wrapping inotify, ReadDirChangesW,
+// FSEvents, kqueue and poller implementations.
+//
+// The watcher implementation is expected to do its own mapping between paths and
+// create watchers if underlying event notification does not support it. For
+// the ease of implementation it is guaranteed that paths provided via Watch and
+// Unwatch methods are absolute and clean.
+type watcher interface {
+	// Watch requests a watcher creation for the given path and given event set.
+	Watch(path string, event Event) error
+
+	// Unwatch requests a watcher deletion for the given path and given event set.
+	Unwatch(path string) error
+
+	// Rewatch provides a functionality for modifying existing watch-points, like
+	// expanding its event set.
+	//
+	// Rewatch modifies existing watch-point under for the given path. It passes
+	// the existing event set currently registered for the given path, and the
+	// new, requested event set.
+	//
+	// It is guaranteed that Tree will not pass to Rewatch zero value for any
+	// of its arguments. If old == new and watcher can be upgraded to
+	// recursiveWatcher interface, a watch for the corresponding path is expected
+	// to be changed from recursive to the non-recursive one.
+	Rewatch(path string, old, new Event) error
+
+	// Close unwatches all paths that are registered. When Close returns, it
+	// is expected it will report no more events.
+	Close() error
+}
+
+// RecursiveWatcher is an interface for a Watcher for those OS, which do support
+// recursive watching over directories.
+type recursiveWatcher interface {
+	RecursiveWatch(path string, event Event) error
+
+	// RecursiveUnwatch removes a recursive watch-point given by the path. For
+	// native recursive implementation there is no difference in functionality
+	// between Unwatch and RecursiveUnwatch, however for those platforms, that
+	// requires emulation for recursive watch-points, the implementation differs.
+	RecursiveUnwatch(path string) error
+
+	// RecursiveRewatcher provides a functionality for modifying and/or relocating
+	// existing recursive watch-points.
+	//
+	// To relocate a watch-point means to unwatch oldpath and set a watch-point on
+	// newpath.
+	//
+	// To modify a watch-point means either to expand or shrink its event set.
+	//
+	// Tree can want to either relocate, modify or relocate and modify a watch-point
+	// via single RecursiveRewatch call.
+	//
+	// If oldpath == newpath, the watch-point is expected to change its event set value
+	// from oldevent to newevent.
+	//
+	// If oldevent == newevent, the watch-point is expected to relocate from oldpath
+	// to the newpath.
+	//
+	// If oldpath != newpath and oldevent != newevent, the watch-point is expected
+	// to relocate from oldpath to the newpath first and then change its event set
+	// value from oldevent to the newevent. In other words the end result must be
+	// a watch-point set on newpath with newevent value of its event set.
+	//
+	// It is guaranteed that Tree will not pass to RecurisveRewatcha zero value
+	// for any of its arguments. If oldpath == newpath and oldevent == newevent,
+	// a watch for the corresponding path is expected to be changed for
+	// non-recursive to the recursive one.
+	RecursiveRewatch(oldpath, newpath string, oldevent, newevent Event) error
+}