1 files changed, 354 insertions, 0 deletions
diff --git a/vendor/github.com/rjeczalik/notify/tree_recursive.go b/vendor/github.com/rjeczalik/notify/tree_recursive.go
new file mode 100644
index 000000000..7f00dfe35
--- /dev/null
+++ b/vendor/github.com/rjeczalik/notify/tree_recursive.go
@@ -0,0 +1,354 @@
+// 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 "sync"
+
+// watchAdd TODO(rjeczalik)
+func watchAdd(nd node, c chan<- EventInfo, e Event) eventDiff {
+	diff := nd.Watch.Add(c, e)
+	if wp := nd.Child[""].Watch; len(wp) != 0 {
+		e = wp.Total()
+		diff[0] |= e
+		diff[1] |= e
+		if diff[0] == diff[1] {
+			return none
+		}
+	}
+	return diff
+}
+
+// watchAddInactive TODO(rjeczalik)
+func watchAddInactive(nd node, c chan<- EventInfo, e Event) eventDiff {
+	wp := nd.Child[""].Watch
+	if wp == nil {
+		wp = make(watchpoint)
+		nd.Child[""] = node{Watch: wp}
+	}
+	diff := wp.Add(c, e)
+	e = nd.Watch.Total()
+	diff[0] |= e
+	diff[1] |= e
+	if diff[0] == diff[1] {
+		return none
+	}
+	return diff
+}
+
+// watchCopy TODO(rjeczalik)
+func watchCopy(src, dst node) {
+	for c, e := range src.Watch {
+		if c == nil {
+			continue
+		}
+		watchAddInactive(dst, c, e)
+	}
+	if wpsrc := src.Child[""].Watch; len(wpsrc) != 0 {
+		wpdst := dst.Child[""].Watch
+		for c, e := range wpsrc {
+			if c == nil {
+				continue
+			}
+			wpdst.Add(c, e)
+		}
+	}
+}
+
+// watchDel TODO(rjeczalik)
+func watchDel(nd node, c chan<- EventInfo, e Event) eventDiff {
+	diff := nd.Watch.Del(c, e)
+	if wp := nd.Child[""].Watch; len(wp) != 0 {
+		diffInactive := wp.Del(c, e)
+		e = wp.Total()
+		// TODO(rjeczalik): add e if e != all?
+		diff[0] |= diffInactive[0] | e
+		diff[1] |= diffInactive[1] | e
+		if diff[0] == diff[1] {
+			return none
+		}
+	}
+	return diff
+}
+
+// watchTotal TODO(rjeczalik)
+func watchTotal(nd node) Event {
+	e := nd.Watch.Total()
+	if wp := nd.Child[""].Watch; len(wp) != 0 {
+		e |= wp.Total()
+	}
+	return e
+}
+
+// watchIsRecursive TODO(rjeczalik)
+func watchIsRecursive(nd node) bool {
+	ok := nd.Watch.IsRecursive()
+	// TODO(rjeczalik): add a test for len(wp) != 0 change the condition.
+	if wp := nd.Child[""].Watch; len(wp) != 0 {
+		// If a watchpoint holds inactive watchpoints, it means it's a parent
+		// one, which is recursive by nature even though it may be not recursive
+		// itself.
+		ok = true
+	}
+	return ok
+}
+
+// recursiveTree TODO(rjeczalik)
+type recursiveTree struct {
+	rw   sync.RWMutex // protects root
+	root root
+	// TODO(rjeczalik): merge watcher + recursiveWatcher after #5 and #6
+	w interface {
+		watcher
+		recursiveWatcher
+	}
+	c chan EventInfo
+}
+
+// newRecursiveTree TODO(rjeczalik)
+func newRecursiveTree(w recursiveWatcher, c chan EventInfo) *recursiveTree {
+	t := &recursiveTree{
+		root: root{nd: newnode("")},
+		w: struct {
+			watcher
+			recursiveWatcher
+		}{w.(watcher), w},
+		c: c,
+	}
+	go t.dispatch()
+	return t
+}
+
+// dispatch TODO(rjeczalik)
+func (t *recursiveTree) dispatch() {
+	for ei := range t.c {
+		dbgprintf("dispatching %v on %q", ei.Event(), ei.Path())
+		go func(ei EventInfo) {
+			nd, ok := node{}, false
+			dir, base := split(ei.Path())
+			fn := func(it node, isbase bool) error {
+				if isbase {
+					nd = it
+				} else {
+					it.Watch.Dispatch(ei, recursive)
+				}
+				return nil
+			}
+			t.rw.RLock()
+			defer t.rw.RUnlock()
+			// Notify recursive watchpoints found on the path.
+			if err := t.root.WalkPath(dir, fn); err != nil {
+				dbgprint("dispatch did not reach leaf:", err)
+				return
+			}
+			// Notify parent watchpoint.
+			nd.Watch.Dispatch(ei, 0)
+			// If leaf watchpoint exists, notify it.
+			if nd, ok = nd.Child[base]; ok {
+				nd.Watch.Dispatch(ei, 0)
+			}
+		}(ei)
+	}
+}
+
+// Watch TODO(rjeczalik)
+func (t *recursiveTree) Watch(path string, c chan<- EventInfo, events ...Event) error {
+	if c == nil {
+		panic("notify: Watch using nil channel")
+	}
+	// Expanding with empty event set is a nop.
+	if len(events) == 0 {
+		return nil
+	}
+	path, isrec, err := cleanpath(path)
+	if err != nil {
+		return err
+	}
+	eventset := joinevents(events)
+	if isrec {
+		eventset |= recursive
+	}
+	t.rw.Lock()
+	defer t.rw.Unlock()
+	// case 1: cur is a child
+	//
+	// Look for parent watch which already covers the given path.
+	parent := node{}
+	self := false
+	err = t.root.WalkPath(path, func(nd node, isbase bool) error {
+		if watchTotal(nd) != 0 {
+			parent = nd
+			self = isbase
+			return errSkip
+		}
+		return nil
+	})
+	cur := t.root.Add(path) // add after the walk, so it's less to traverse
+	if err == nil && parent.Watch != nil {
+		// Parent watch found. Register inactive watchpoint, so we have enough
+		// information to shrink the eventset on eventual Stop.
+		// return t.resetwatchpoint(parent, parent, c, eventset|inactive)
+		var diff eventDiff
+		if self {
+			diff = watchAdd(cur, c, eventset)
+		} else {
+			diff = watchAddInactive(parent, c, eventset)
+		}
+		switch {
+		case diff == none:
+			// the parent watchpoint already covers requested subtree with its
+			// eventset
+		case diff[0] == 0:
+			// TODO(rjeczalik): cleanup this panic after implementation is stable
+			panic("dangling watchpoint: " + parent.Name)
+		default:
+			if isrec || watchIsRecursive(parent) {
+				err = t.w.RecursiveRewatch(parent.Name, parent.Name, diff[0], diff[1])
+			} else {
+				err = t.w.Rewatch(parent.Name, diff[0], diff[1])
+			}
+			if err != nil {
+				watchDel(parent, c, diff.Event())
+				return err
+			}
+			watchAdd(cur, c, eventset)
+			// TODO(rjeczalik): account top-most path for c
+			return nil
+		}
+		if !self {
+			watchAdd(cur, c, eventset)
+		}
+		return nil
+	}
+	// case 2: cur is new parent
+	//
+	// Look for children nodes, unwatch n-1 of them and rewatch the last one.
+	var children []node
+	fn := func(nd node) error {
+		if len(nd.Watch) == 0 {
+			return nil
+		}
+		children = append(children, nd)
+		return errSkip
+	}
+	switch must(cur.Walk(fn)); len(children) {
+	case 0:
+		// no child watches, cur holds a new watch
+	case 1:
+		watchAdd(cur, c, eventset) // TODO(rjeczalik): update cache c subtree root?
+		watchCopy(children[0], cur)
+		err = t.w.RecursiveRewatch(children[0].Name, cur.Name, watchTotal(children[0]),
+			watchTotal(cur))
+		if err != nil {
+			// Clean inactive watchpoint. The c chan did not exist before.
+			cur.Child[""] = node{}
+			delete(cur.Watch, c)
+			return err
+		}
+		return nil
+	default:
+		watchAdd(cur, c, eventset)
+		// Copy children inactive watchpoints to the new parent.
+		for _, nd := range children {
+			watchCopy(nd, cur)
+		}
+		// Watch parent subtree.
+		if err = t.w.RecursiveWatch(cur.Name, watchTotal(cur)); err != nil {
+			// Clean inactive watchpoint. The c chan did not exist before.
+			cur.Child[""] = node{}
+			delete(cur.Watch, c)
+			return err
+		}
+		// Unwatch children subtrees.
+		var e error
+		for _, nd := range children {
+			if watchIsRecursive(nd) {
+				e = t.w.RecursiveUnwatch(nd.Name)
+			} else {
+				e = t.w.Unwatch(nd.Name)
+			}
+			if e != nil {
+				err = nonil(err, e)
+				// TODO(rjeczalik): child is still watched, warn all its watchpoints
+				// about possible duplicate events via Error event
+			}
+		}
+		return err
+	}
+	// case 3: cur is new, alone node
+	switch diff := watchAdd(cur, c, eventset); {
+	case diff == none:
+		// TODO(rjeczalik): cleanup this panic after implementation is stable
+		panic("watch requested but no parent watchpoint found: " + cur.Name)
+	case diff[0] == 0:
+		if isrec {
+			err = t.w.RecursiveWatch(cur.Name, diff[1])
+		} else {
+			err = t.w.Watch(cur.Name, diff[1])
+		}
+		if err != nil {
+			watchDel(cur, c, diff.Event())
+			return err
+		}
+	default:
+		// TODO(rjeczalik): cleanup this panic after implementation is stable
+		panic("watch requested but no parent watchpoint found: " + cur.Name)
+	}
+	return nil
+}
+
+// Stop TODO(rjeczalik)
+//
+// TODO(rjeczalik): Split parent watchpoint - transfer watches to children
+// if parent is no longer needed. This carries a risk that underlying
+// watcher calls could fail - reconsider if it's worth the effort.
+func (t *recursiveTree) Stop(c chan<- EventInfo) {
+	var err error
+	fn := func(nd node) (e error) {
+		diff := watchDel(nd, c, all)
+		switch {
+		case diff == none && watchTotal(nd) == 0:
+			// TODO(rjeczalik): There's no watchpoints deeper in the tree,
+			// probably we should remove the nodes as well.
+			return nil
+		case diff == none:
+			// Removing c from nd does not require shrinking its eventset.
+		case diff[1] == 0:
+			if watchIsRecursive(nd) {
+				e = t.w.RecursiveUnwatch(nd.Name)
+			} else {
+				e = t.w.Unwatch(nd.Name)
+			}
+		default:
+			if watchIsRecursive(nd) {
+				e = t.w.RecursiveRewatch(nd.Name, nd.Name, diff[0], diff[1])
+			} else {
+				e = t.w.Rewatch(nd.Name, diff[0], diff[1])
+			}
+		}
+		fn := func(nd node) error {
+			watchDel(nd, c, all)
+			return nil
+		}
+		err = nonil(err, e, nd.Walk(fn))
+		// TODO(rjeczalik): if e != nil store dummy chan in nd.Watch just to
+		// retry un/rewatching next time and/or let the user handle the failure
+		// vie Error event?
+		return errSkip
+	}
+	t.rw.Lock()
+	e := t.root.Walk("", fn) // TODO(rjeczalik): use max root per c
+	t.rw.Unlock()
+	if e != nil {
+		err = nonil(err, e)
+	}
+	dbgprintf("Stop(%p) error: %v\n", c, err)
+}
+
+// Close TODO(rjeczalik)
+func (t *recursiveTree) Close() error {
+	err := t.w.Close()
+	close(t.c)
+	return err
+}