Godeps: add github.com/rjeczalik/notify

This commit is contained in:
Felix Lange 2016-03-18 19:37:29 +01:00
parent ee1682ffe6
commit ef63e9af55
37 changed files with 4702 additions and 0 deletions

4
Godeps/Godeps.json generated

@ -119,6 +119,10 @@
"ImportPath": "github.com/rcrowley/go-metrics", "ImportPath": "github.com/rcrowley/go-metrics",
"Rev": "51425a2415d21afadfd55cd93432c0bc69e9598d" "Rev": "51425a2415d21afadfd55cd93432c0bc69e9598d"
}, },
{
"ImportPath": "github.com/rjeczalik/notify",
"Rev": "5dd6205716539662f8f14ab513552b41eab69d5d"
},
{ {
"ImportPath": "github.com/robertkrimen/otto", "ImportPath": "github.com/robertkrimen/otto",
"Rev": "53221230c215611a90762720c9042ac782ef74ee" "Rev": "53221230c215611a90762720c9042ac782ef74ee"

@ -0,0 +1,88 @@
# Created by https://www.gitignore.io
### OSX ###
.DS_Store
.AppleDouble
.LSOverride
# Icon must end with two \r
Icon
# Thumbnails
._*
# Files that might appear on external disk
.Spotlight-V100
.Trashes
# Directories potentially created on remote AFP share
.AppleDB
.AppleDesktop
Network Trash Folder
Temporary Items
.apdisk
### Windows ###
# Windows image file caches
Thumbs.db
ehthumbs.db
# Folder config file
Desktop.ini
# Recycle Bin used on file shares
$RECYCLE.BIN/
# Windows Installer files
*.cab
*.msi
*.msm
*.msp
# Windows shortcuts
*.lnk
### Linux ###
*~
# KDE directory preferences
.directory
### Go ###
# Compiled Object files, Static and Dynamic libs (Shared Objects)
*.o
*.a
*.so
# Folders
_obj
_test
# Architecture specific extensions/prefixes
*.[568vq]
[568vq].out
*.cgo1.go
*.cgo2.c
_cgo_defun.c
_cgo_gotypes.go
_cgo_export.*
_testmain.go
*.exe
*.test
*.prof
### vim ###
[._]*.s[a-w][a-z]
[._]s[a-w][a-z]
*.un~
Session.vim
.netrwhist
*~

@ -0,0 +1,30 @@
language: go
go:
- 1.4.3
- 1.6
os:
- linux
- osx
matrix:
include:
- os: osx
go: 1.6
env:
- GOFLAGS="-tags kqueue"
env:
global:
- GOBIN=$HOME/bin
- PATH=$HOME/bin:$PATH
install:
- go get golang.org/x/tools/cmd/vet
- go get -t -v ./...
script:
- go tool vet -all .
- go install $GOFLAGS ./...
- go test -v -race $GOFLAGS ./...

@ -0,0 +1,10 @@
# List of individuals who contributed to the Notify package.
#
# The up-to-date list of the authors one may obtain with:
#
# ~ $ git shortlog -es | cut -f2 | rev | uniq -f1 | rev
#
Pawel Blaszczyk <blaszczykpb@gmail.com>
Pawel Knap <pawelknap88@gmail.com>
Rafal Jeczalik <rjeczalik@gmail.com>

@ -0,0 +1,21 @@
The MIT License (MIT)
Copyright (c) 2014-2015 The Notify Authors
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.

@ -0,0 +1,21 @@
notify [![GoDoc](https://godoc.org/github.com/rjeczalik/notify?status.svg)](https://godoc.org/github.com/rjeczalik/notify) [![Build Status](https://img.shields.io/travis/rjeczalik/notify/master.svg)](https://travis-ci.org/rjeczalik/notify "inotify + FSEvents + kqueue") [![Build status](https://img.shields.io/appveyor/ci/rjeczalik/notify-246.svg)](https://ci.appveyor.com/project/rjeczalik/notify-246 "ReadDirectoryChangesW") [![Coverage Status](https://img.shields.io/coveralls/rjeczalik/notify/master.svg)](https://coveralls.io/r/rjeczalik/notify?branch=master)
======
Filesystem event notification library on steroids. (under active development)
*Documentation*
[godoc.org/github.com/rjeczalik/notify](https://godoc.org/github.com/rjeczalik/notify)
*Installation*
```
~ $ go get -u github.com/rjeczalik/notify
```
*Projects using notify*
- [github.com/rjeczalik/cmd/notify](https://godoc.org/github.com/rjeczalik/cmd/notify)
- [github.com/cortesi/devd](https://github.com/cortesi/devd)
- [github.com/cortesi/modd](https://github.com/cortesi/modd)

@ -0,0 +1,24 @@
version: "{build}"
os: Windows Server 2012 R2
clone_folder: c:\projects\src\github.com\rjeczalik\notify
environment:
PATH: c:\projects\bin;%PATH%
GOPATH: c:\projects
NOTIFY_TIMEOUT: 5s
install:
- go version
- go get golang.org/x/tools/cmd/vet
- go get -v -t ./...
build_script:
- go tool vet -all .
- go build ./...
- go test -v -race ./...
test: off
deploy: off

@ -0,0 +1,11 @@
// 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.
// +build !debug
package notify
func dbgprint(...interface{}) {}
func dbgprintf(string, ...interface{}) {}

@ -0,0 +1,43 @@
// 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.
// +build debug
package notify
import (
"fmt"
"os"
"runtime"
"strings"
)
func dbgprint(v ...interface{}) {
fmt.Printf("[D] ")
fmt.Print(v...)
fmt.Printf("\n\n")
}
func dbgprintf(format string, v ...interface{}) {
fmt.Printf("[D] ")
fmt.Printf(format, v...)
fmt.Printf("\n\n")
}
func dbgcallstack(max int) []string {
pc, stack := make([]uintptr, max), make([]string, 0, max)
runtime.Callers(2, pc)
for _, pc := range pc {
if f := runtime.FuncForPC(pc); f != nil {
fname := f.Name()
idx := strings.LastIndex(fname, string(os.PathSeparator))
if idx != -1 {
stack = append(stack, fname[idx+1:])
} else {
stack = append(stack, fname)
}
}
}
return stack
}

@ -0,0 +1,40 @@
// 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 implements access to filesystem events.
//
// Notify is a high-level abstraction over filesystem watchers like inotify,
// kqueue, FSEvents, FEN or ReadDirectoryChangesW. Watcher implementations are
// split into two groups: ones that natively support recursive notifications
// (FSEvents and ReadDirectoryChangesW) and ones that do not (inotify, kqueue, FEN).
// For more details see watcher and recursiveWatcher interfaces in watcher.go
// source file.
//
// On top of filesystem watchers notify maintains a watchpoint tree, which provides
// strategy for creating and closing filesystem watches and dispatching filesystem
// events to user channels.
//
// An event set is just an event list joint using bitwise OR operator
// into a single event value.
//
// A filesystem watch or just a watch is platform-specific entity which represents
// a single path registered for notifications for specific event set. Setting a watch
// means using platform-specific API calls for creating / initializing said watch.
// For each watcher the API call is:
//
// - FSEvents: FSEventStreamCreate
// - inotify: notify_add_watch
// - kqueue: kevent
// - ReadDirectoryChangesW: CreateFile+ReadDirectoryChangesW
// - FEN: port_get
//
// To rewatch means to either shrink or expand an event set that was previously
// registered during watch operation for particular filesystem watch.
//
// A watchpoint is a list of user channel and event set pairs for particular
// path (watchpoint tree's node). A single watchpoint can contain multiple
// different user channels registered to listen for one or more events. A single
// user channel can be registered in one or more watchpoints, recurisve and
// non-recursive ones as well.
package notify

@ -0,0 +1,143 @@
// 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 (
"fmt"
"strings"
)
// Event represents the type of filesystem action.
//
// Number of available event values is dependent on the target system or the
// watcher implmenetation used (e.g. it's possible to use either kqueue or
// FSEvents on Darwin).
//
// Please consult documentation for your target platform to see list of all
// available events.
type Event uint32
// Create, Remove, Write and Rename are the only event values guaranteed to be
// present on all platforms.
const (
Create = osSpecificCreate
Remove = osSpecificRemove
Write = osSpecificWrite
Rename = osSpecificRename
// All is handful alias for all platform-independent event values.
All = Create | Remove | Write | Rename
)
const internal = recursive | omit
// String implements fmt.Stringer interface.
func (e Event) String() string {
var s []string
for _, strmap := range []map[Event]string{estr, osestr} {
for ev, str := range strmap {
if e&ev == ev {
s = append(s, str)
}
}
}
return strings.Join(s, "|")
}
// EventInfo describes an event reported by the underlying filesystem notification
// subsystem.
//
// It always describes single event, even if the OS reported a coalesced action.
// Reported path is absolute and clean.
//
// For non-recursive watchpoints its base is always equal to the path passed
// to corresponding Watch call.
//
// The value of Sys if system-dependent and can be nil.
//
// Sys
//
// Under Darwin (FSEvents) Sys() always returns a non-nil *notify.FSEvent value,
// which is defined as:
//
// type FSEvent struct {
// Path string // real path of the file or directory
// ID uint64 // ID of the event (FSEventStreamEventId)
// Flags uint32 // joint FSEvents* flags (FSEventStreamEventFlags)
// }
//
// For possible values of Flags see Darwin godoc for notify or FSEvents
// documentation for FSEventStreamEventFlags constants:
//
// https://developer.apple.com/library/mac/documentation/Darwin/Reference/FSEvents_Ref/index.html#//apple_ref/doc/constant_group/FSEventStreamEventFlags
//
// Under Linux (inotify) Sys() always returns a non-nil *syscall.InotifyEvent
// value, defined as:
//
// type InotifyEvent struct {
// Wd int32 // Watch descriptor
// Mask uint32 // Mask describing event
// Cookie uint32 // Unique cookie associating related events (for rename(2))
// Len uint32 // Size of name field
// Name [0]uint8 // Optional null-terminated name
// }
//
// More information about inotify masks and the usage of inotify_event structure
// can be found at:
//
// http://man7.org/linux/man-pages/man7/inotify.7.html
//
// Under Darwin, DragonFlyBSD, FreeBSD, NetBSD, OpenBSD (kqueue) Sys() always
// returns a non-nil *notify.Kevent value, which is defined as:
//
// type Kevent struct {
// Kevent *syscall.Kevent_t // Kevent is a kqueue specific structure
// FI os.FileInfo // FI describes file/dir
// }
//
// More information about syscall.Kevent_t can be found at:
//
// https://www.freebsd.org/cgi/man.cgi?query=kqueue
//
// Under Windows (ReadDirectoryChangesW) Sys() always returns nil. The documentation
// of watcher's WinAPI function can be found at:
//
// https://msdn.microsoft.com/en-us/library/windows/desktop/aa365465%28v=vs.85%29.aspx
type EventInfo interface {
Event() Event // event value for the filesystem action
Path() string // real path of the file or directory
Sys() interface{} // underlying data source (can return nil)
}
type isDirer interface {
isDir() (bool, error)
}
var _ fmt.Stringer = (*event)(nil)
var _ isDirer = (*event)(nil)
// String implements fmt.Stringer interface.
func (e *event) String() string {
return e.Event().String() + `: "` + e.Path() + `"`
}
var estr = map[Event]string{
Create: "notify.Create",
Remove: "notify.Remove",
Write: "notify.Write",
Rename: "notify.Rename",
// Display name for recursive event is added only for debugging
// purposes. It's an internal event after all and won't be exposed to the
// user. Having Recursive event printable is helpful, e.g. for reading
// testing failure messages:
//
// --- FAIL: TestWatchpoint (0.00 seconds)
// watchpoint_test.go:64: want diff=[notify.Remove notify.Create|notify.Remove];
// got [notify.Remove notify.Remove|notify.Create] (i=1)
//
// Yup, here the diff have Recursive event inside. Go figure.
recursive: "recursive",
omit: "omit",
}

@ -0,0 +1,46 @@
// 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.
// +build solaris
package notify
const (
osSpecificCreate Event = 0x00000100 << iota
osSpecificRemove
osSpecificWrite
osSpecificRename
// internal
// recursive is used to distinguish recursive eventsets from non-recursive ones
recursive
// omit is used for dispatching internal events; only those events are sent
// for which both the event and the watchpoint has omit in theirs event sets.
omit
)
const (
FileAccess = fileAccess
FileModified = fileModified
FileAttrib = fileAttrib
FileDelete = fileDelete
FileRenameTo = fileRenameTo
FileRenameFrom = fileRenameFrom
FileTrunc = fileTrunc
FileNoFollow = fileNoFollow
Unmounted = unmounted
MountedOver = mountedOver
)
var osestr = map[Event]string{
FileAccess: "notify.FileAccess",
FileModified: "notify.FileModified",
FileAttrib: "notify.FileAttrib",
FileDelete: "notify.FileDelete",
FileRenameTo: "notify.FileRenameTo",
FileRenameFrom: "notify.FileRenameFrom",
FileTrunc: "notify.FileTrunc",
FileNoFollow: "notify.FileNoFollow",
Unmounted: "notify.Unmounted",
MountedOver: "notify.MountedOver",
}

@ -0,0 +1,71 @@
// 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.
// +build darwin,!kqueue
package notify
const (
osSpecificCreate = Event(FSEventsCreated)
osSpecificRemove = Event(FSEventsRemoved)
osSpecificWrite = Event(FSEventsModified)
osSpecificRename = Event(FSEventsRenamed)
// internal = Event(0x100000)
// recursive is used to distinguish recursive eventsets from non-recursive ones
recursive = Event(0x200000)
// omit is used for dispatching internal events; only those events are sent
// for which both the event and the watchpoint has omit in theirs event sets.
omit = Event(0x400000)
)
// FSEvents specific event values.
const (
FSEventsMustScanSubDirs Event = 0x00001
FSEventsUserDropped = 0x00002
FSEventsKernelDropped = 0x00004
FSEventsEventIdsWrapped = 0x00008
FSEventsHistoryDone = 0x00010
FSEventsRootChanged = 0x00020
FSEventsMount = 0x00040
FSEventsUnmount = 0x00080
FSEventsCreated = 0x00100
FSEventsRemoved = 0x00200
FSEventsInodeMetaMod = 0x00400
FSEventsRenamed = 0x00800
FSEventsModified = 0x01000
FSEventsFinderInfoMod = 0x02000
FSEventsChangeOwner = 0x04000
FSEventsXattrMod = 0x08000
FSEventsIsFile = 0x10000
FSEventsIsDir = 0x20000
FSEventsIsSymlink = 0x40000
)
var osestr = map[Event]string{
FSEventsMustScanSubDirs: "notify.FSEventsMustScanSubDirs",
FSEventsUserDropped: "notify.FSEventsUserDropped",
FSEventsKernelDropped: "notify.FSEventsKernelDropped",
FSEventsEventIdsWrapped: "notify.FSEventsEventIdsWrapped",
FSEventsHistoryDone: "notify.FSEventsHistoryDone",
FSEventsRootChanged: "notify.FSEventsRootChanged",
FSEventsMount: "notify.FSEventsMount",
FSEventsUnmount: "notify.FSEventsUnmount",
FSEventsInodeMetaMod: "notify.FSEventsInodeMetaMod",
FSEventsFinderInfoMod: "notify.FSEventsFinderInfoMod",
FSEventsChangeOwner: "notify.FSEventsChangeOwner",
FSEventsXattrMod: "notify.FSEventsXattrMod",
FSEventsIsFile: "notify.FSEventsIsFile",
FSEventsIsDir: "notify.FSEventsIsDir",
FSEventsIsSymlink: "notify.FSEventsIsSymlink",
}
type event struct {
fse FSEvent
event Event
}
func (ei *event) Event() Event { return ei.event }
func (ei *event) Path() string { return ei.fse.Path }
func (ei *event) Sys() interface{} { return &ei.fse }
func (ei *event) isDir() (bool, error) { return ei.fse.Flags&FSEventsIsDir != 0, nil }

@ -0,0 +1,75 @@
// 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.
// +build linux
package notify
import "syscall"
// Platform independent event values.
const (
osSpecificCreate Event = 0x100000 << iota
osSpecificRemove
osSpecificWrite
osSpecificRename
// internal
// recursive is used to distinguish recursive eventsets from non-recursive ones
recursive
// omit is used for dispatching internal events; only those events are sent
// for which both the event and the watchpoint has omit in theirs event sets.
omit
)
// Inotify specific masks are legal, implemented events that are guaranteed to
// work with notify package on linux-based systems.
const (
InAccess = Event(syscall.IN_ACCESS) // File was accessed
InModify = Event(syscall.IN_MODIFY) // File was modified
InAttrib = Event(syscall.IN_ATTRIB) // Metadata changed
InCloseWrite = Event(syscall.IN_CLOSE_WRITE) // Writtable file was closed
InCloseNowrite = Event(syscall.IN_CLOSE_NOWRITE) // Unwrittable file closed
InOpen = Event(syscall.IN_OPEN) // File was opened
InMovedFrom = Event(syscall.IN_MOVED_FROM) // File was moved from X
InMovedTo = Event(syscall.IN_MOVED_TO) // File was moved to Y
InCreate = Event(syscall.IN_CREATE) // Subfile was created
InDelete = Event(syscall.IN_DELETE) // Subfile was deleted
InDeleteSelf = Event(syscall.IN_DELETE_SELF) // Self was deleted
InMoveSelf = Event(syscall.IN_MOVE_SELF) // Self was moved
)
var osestr = map[Event]string{
InAccess: "notify.InAccess",
InModify: "notify.InModify",
InAttrib: "notify.InAttrib",
InCloseWrite: "notify.InCloseWrite",
InCloseNowrite: "notify.InCloseNowrite",
InOpen: "notify.InOpen",
InMovedFrom: "notify.InMovedFrom",
InMovedTo: "notify.InMovedTo",
InCreate: "notify.InCreate",
InDelete: "notify.InDelete",
InDeleteSelf: "notify.InDeleteSelf",
InMoveSelf: "notify.InMoveSelf",
}
// Inotify behavior events are not **currently** supported by notify package.
const (
inDontFollow = Event(syscall.IN_DONT_FOLLOW)
inExclUnlink = Event(syscall.IN_EXCL_UNLINK)
inMaskAdd = Event(syscall.IN_MASK_ADD)
inOneshot = Event(syscall.IN_ONESHOT)
inOnlydir = Event(syscall.IN_ONLYDIR)
)
type event struct {
sys syscall.InotifyEvent
path string
event Event
}
func (e *event) Event() Event { return e.event }
func (e *event) Path() string { return e.path }
func (e *event) Sys() interface{} { return &e.sys }
func (e *event) isDir() (bool, error) { return e.sys.Mask&syscall.IN_ISDIR != 0, nil }

@ -0,0 +1,59 @@
// 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.
// +build darwin,kqueue dragonfly freebsd netbsd openbsd
package notify
import "syscall"
// TODO(pblaszczyk): ensure in runtime notify built-in event values do not
// overlap with platform-defined ones.
// Platform independent event values.
const (
osSpecificCreate Event = 0x0100 << iota
osSpecificRemove
osSpecificWrite
osSpecificRename
// internal
// recursive is used to distinguish recursive eventsets from non-recursive ones
recursive
// omit is used for dispatching internal events; only those events are sent
// for which both the event and the watchpoint has omit in theirs event sets.
omit
)
const (
// NoteDelete is an even reported when the unlink() system call was called
// on the file referenced by the descriptor.
NoteDelete = Event(syscall.NOTE_DELETE)
// NoteWrite is an event reported when a write occurred on the file
// referenced by the descriptor.
NoteWrite = Event(syscall.NOTE_WRITE)
// NoteExtend is an event reported when the file referenced by the
// descriptor was extended.
NoteExtend = Event(syscall.NOTE_EXTEND)
// NoteAttrib is an event reported when the file referenced
// by the descriptor had its attributes changed.
NoteAttrib = Event(syscall.NOTE_ATTRIB)
// NoteLink is an event reported when the link count on the file changed.
NoteLink = Event(syscall.NOTE_LINK)
// NoteRename is an event reported when the file referenced
// by the descriptor was renamed.
NoteRename = Event(syscall.NOTE_RENAME)
// NoteRevoke is an event reported when access to the file was revoked via
// revoke(2) or the underlying file system was unmounted.
NoteRevoke = Event(syscall.NOTE_REVOKE)
)
var osestr = map[Event]string{
NoteDelete: "notify.NoteDelete",
NoteWrite: "notify.NoteWrite",
NoteExtend: "notify.NoteExtend",
NoteAttrib: "notify.NoteAttrib",
NoteLink: "notify.NoteLink",
NoteRename: "notify.NoteRename",
NoteRevoke: "notify.NoteRevoke",
}

@ -0,0 +1,108 @@
// 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.
// +build windows
package notify
import (
"os"
"path/filepath"
"syscall"
)
// Platform independent event values.
const (
osSpecificCreate Event = 1 << (20 + iota)
osSpecificRemove
osSpecificWrite
osSpecificRename
// recursive is used to distinguish recursive eventsets from non-recursive ones
recursive
// omit is used for dispatching internal events; only those events are sent
// for which both the event and the watchpoint has omit in theirs event sets.
omit
// dirmarker TODO(pknap)
dirmarker
)
// ReadDirectoryChangesW filters.
const (
FileNotifyChangeFileName = Event(syscall.FILE_NOTIFY_CHANGE_FILE_NAME)
FileNotifyChangeDirName = Event(syscall.FILE_NOTIFY_CHANGE_DIR_NAME)
FileNotifyChangeAttributes = Event(syscall.FILE_NOTIFY_CHANGE_ATTRIBUTES)
FileNotifyChangeSize = Event(syscall.FILE_NOTIFY_CHANGE_SIZE)
FileNotifyChangeLastWrite = Event(syscall.FILE_NOTIFY_CHANGE_LAST_WRITE)
FileNotifyChangeLastAccess = Event(syscall.FILE_NOTIFY_CHANGE_LAST_ACCESS)
FileNotifyChangeCreation = Event(syscall.FILE_NOTIFY_CHANGE_CREATION)
FileNotifyChangeSecurity = Event(syscallFileNotifyChangeSecurity)
)
const (
fileNotifyChangeAll = 0x17f // logical sum of all FileNotifyChange* events.
fileNotifyChangeModified = fileNotifyChangeAll &^ (FileNotifyChangeFileName | FileNotifyChangeDirName)
)
// according to: http://msdn.microsoft.com/en-us/library/windows/desktop/aa365465(v=vs.85).aspx
// this flag should be declared in: http://golang.org/src/pkg/syscall/ztypes_windows.go
const syscallFileNotifyChangeSecurity = 0x00000100
// ReadDirectoryChangesW actions.
const (
FileActionAdded = Event(syscall.FILE_ACTION_ADDED) << 12
FileActionRemoved = Event(syscall.FILE_ACTION_REMOVED) << 12
FileActionModified = Event(syscall.FILE_ACTION_MODIFIED) << 14
FileActionRenamedOldName = Event(syscall.FILE_ACTION_RENAMED_OLD_NAME) << 15
FileActionRenamedNewName = Event(syscall.FILE_ACTION_RENAMED_NEW_NAME) << 16
)
const fileActionAll = 0x7f000 // logical sum of all FileAction* events.
var osestr = map[Event]string{
FileNotifyChangeFileName: "notify.FileNotifyChangeFileName",
FileNotifyChangeDirName: "notify.FileNotifyChangeDirName",
FileNotifyChangeAttributes: "notify.FileNotifyChangeAttributes",
FileNotifyChangeSize: "notify.FileNotifyChangeSize",
FileNotifyChangeLastWrite: "notify.FileNotifyChangeLastWrite",
FileNotifyChangeLastAccess: "notify.FileNotifyChangeLastAccess",
FileNotifyChangeCreation: "notify.FileNotifyChangeCreation",
FileNotifyChangeSecurity: "notify.FileNotifyChangeSecurity",
FileActionAdded: "notify.FileActionAdded",
FileActionRemoved: "notify.FileActionRemoved",
FileActionModified: "notify.FileActionModified",
FileActionRenamedOldName: "notify.FileActionRenamedOldName",
FileActionRenamedNewName: "notify.FileActionRenamedNewName",
}
const (
fTypeUnknown uint8 = iota
fTypeFile
fTypeDirectory
)
// TODO(ppknap) : doc.
type event struct {
pathw []uint16
name string
ftype uint8
action uint32
filter uint32
e Event
}
func (e *event) Event() Event { return e.e }
func (e *event) Path() string { return filepath.Join(syscall.UTF16ToString(e.pathw), e.name) }
func (e *event) Sys() interface{} { return e.ftype }
func (e *event) isDir() (bool, error) {
if e.ftype != fTypeUnknown {
return e.ftype == fTypeDirectory, nil
}
fi, err := os.Stat(e.Path())
if err != nil {
return false, err
}
return fi.IsDir(), nil
}

@ -0,0 +1,31 @@
// 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.
// +build !darwin,!linux,!freebsd,!dragonfly,!netbsd,!openbsd,!windows
// +build !kqueue,!solaris
package notify
// Platform independent event values.
const (
osSpecificCreate Event = 1 << iota
osSpecificRemove
osSpecificWrite
osSpecificRename
// internal
// recursive is used to distinguish recursive eventsets from non-recursive ones
recursive
// omit is used for dispatching internal events; only those events are sent
// for which both the event and the watchpoint has omit in theirs event sets.
omit
)
var osestr = map[Event]string{}
type event struct{}
func (e *event) Event() (_ Event) { return }
func (e *event) Path() (_ string) { return }
func (e *event) Sys() (_ interface{}) { return }
func (e *event) isDir() (_ bool, _ error) { return }

@ -0,0 +1,22 @@
// 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.
// +build darwin,kqueue dragonfly freebsd netbsd openbsd solaris
package notify
type event struct {
p string
e Event
d bool
pe interface{}
}
func (e *event) Event() Event { return e.e }
func (e *event) Path() string { return e.p }
func (e *event) Sys() interface{} { return e.pe }
func (e *event) isDir() (bool, error) { return e.d, nil }

@ -0,0 +1,271 @@
// 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"
"io/ioutil"
"os"
"path/filepath"
)
var errSkip = errors.New("notify: skip")
type walkPathFunc func(nd node, isbase bool) error
type walkFunc func(node) error
func errnotexist(name string) error {
return &os.PathError{
Op: "Node",
Path: name,
Err: os.ErrNotExist,
}
}
type node struct {
Name string
Watch watchpoint
Child map[string]node
}
func newnode(name string) node {
return node{
Name: name,
Watch: make(watchpoint),
Child: make(map[string]node),
}
}
func (nd node) addchild(name, base string) node {
child, ok := nd.Child[base]
if !ok {
child = newnode(name)
nd.Child[base] = child
}
return child
}
func (nd node) Add(name string) node {
i := indexbase(nd.Name, name)
if i == -1 {
return node{}
}
for j := indexSep(name[i:]); j != -1; j = indexSep(name[i:]) {
nd = nd.addchild(name[:i+j], name[i:i+j])
i += j + 1
}
return nd.addchild(name, name[i:])
}
func (nd node) AddDir(fn walkFunc) error {
stack := []node{nd}
Traverse:
for n := len(stack); n != 0; n = len(stack) {
nd, stack = stack[n-1], stack[:n-1]
switch err := fn(nd); err {
case nil:
case errSkip:
continue Traverse
default:
return err
}
// TODO(rjeczalik): tolerate open failures - add failed names to
// AddDirError and notify users which names are not added to the tree.
fi, err := ioutil.ReadDir(nd.Name)
if err != nil {
return err
}
for _, fi := range fi {
if fi.Mode()&(os.ModeSymlink|os.ModeDir) == os.ModeDir {
name := filepath.Join(nd.Name, fi.Name())
stack = append(stack, nd.addchild(name, name[len(nd.Name)+1:]))
}
}
}
return nil
}
func (nd node) Get(name string) (node, error) {
i := indexbase(nd.Name, name)
if i == -1 {
return node{}, errnotexist(name)
}
ok := false
for j := indexSep(name[i:]); j != -1; j = indexSep(name[i:]) {
if nd, ok = nd.Child[name[i:i+j]]; !ok {
return node{}, errnotexist(name)
}
i += j + 1
}
if nd, ok = nd.Child[name[i:]]; !ok {
return node{}, errnotexist(name)
}
return nd, nil
}
func (nd node) Del(name string) error {
i := indexbase(nd.Name, name)
if i == -1 {
return errnotexist(name)
}
stack := []node{nd}
ok := false
for j := indexSep(name[i:]); j != -1; j = indexSep(name[i:]) {
if nd, ok = nd.Child[name[i:i+j]]; !ok {
return errnotexist(name[:i+j])
}
stack = append(stack, nd)
}
if nd, ok = nd.Child[name[i:]]; !ok {
return errnotexist(name)
}
nd.Child = nil
nd.Watch = nil
for name, i = base(nd.Name), len(stack); i != 0; name, i = base(nd.Name), i-1 {
nd = stack[i-1]
if nd := nd.Child[name]; len(nd.Watch) > 1 || len(nd.Child) != 0 {
break
} else {
nd.Child = nil
nd.Watch = nil
}
delete(nd.Child, name)
}
return nil
}
func (nd node) Walk(fn walkFunc) error {
stack := []node{nd}
Traverse:
for n := len(stack); n != 0; n = len(stack) {
nd, stack = stack[n-1], stack[:n-1]
switch err := fn(nd); err {
case nil:
case errSkip:
continue Traverse
default:
return err
}
for name, nd := range nd.Child {
if name == "" {
// Node storing inactive watchpoints has empty name, skip it
// form traversing. Root node has also an empty name, but it
// never has a parent node.
continue
}
stack = append(stack, nd)
}
}
return nil
}
func (nd node) WalkPath(name string, fn walkPathFunc) error {
i := indexbase(nd.Name, name)
if i == -1 {
return errnotexist(name)
}
ok := false
for j := indexSep(name[i:]); j != -1; j = indexSep(name[i:]) {
switch err := fn(nd, false); err {
case nil:
case errSkip:
return nil
default:
return err
}
if nd, ok = nd.Child[name[i:i+j]]; !ok {
return errnotexist(name[:i+j])
}
i += j + 1
}
switch err := fn(nd, false); err {
case nil:
case errSkip:
return nil
default:
return err
}
if nd, ok = nd.Child[name[i:]]; !ok {
return errnotexist(name)
}
switch err := fn(nd, true); err {
case nil, errSkip:
return nil
default:
return err
}
}
type root struct {
nd node
}
func (r root) addroot(name string) node {
if vol := filepath.VolumeName(name); vol != "" {
root, ok := r.nd.Child[vol]
if !ok {
root = r.nd.addchild(vol, vol)
}
return root
}
return r.nd
}
func (r root) root(name string) (node, error) {
if vol := filepath.VolumeName(name); vol != "" {
nd, ok := r.nd.Child[vol]
if !ok {
return node{}, errnotexist(name)
}
return nd, nil
}
return r.nd, nil
}
func (r root) Add(name string) node {
return r.addroot(name).Add(name)
}
func (r root) AddDir(dir string, fn walkFunc) error {
return r.Add(dir).AddDir(fn)
}
func (r root) Del(name string) error {
nd, err := r.root(name)
if err != nil {
return err
}
return nd.Del(name)
}
func (r root) Get(name string) (node, error) {
nd, err := r.root(name)
if err != nil {
return node{}, err
}
if nd.Name != name {
if nd, err = nd.Get(name); err != nil {
return node{}, err
}
}
return nd, nil
}
func (r root) Walk(name string, fn walkFunc) error {
nd, err := r.Get(name)
if err != nil {
return err
}
return nd.Walk(fn)
}
func (r root) WalkPath(name string, fn walkPathFunc) error {
nd, err := r.root(name)
if err != nil {
return err
}
return nd.WalkPath(name, fn)
}

@ -0,0 +1,74 @@
// 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.
// BUG(rjeczalik): Notify does not collect watchpoints, when underlying watches
// were removed by their os-specific watcher implementations. Instead users are
// advised to listen on persistant paths to have guarantee they receive events
// for the whole lifetime of their applications (to discuss see #69).
// BUG(ppknap): Linux (inotify) does not support watcher behavior masks like
// InOneshot, InOnlydir etc. Instead users are advised to perform the filtering
// themselves (to discuss see #71).
// BUG(ppknap): Notify was not tested for short path name support under Windows
// (ReadDirectoryChangesW).
// BUG(ppknap): Windows (ReadDirectoryChangesW) cannot recognize which notification
// triggers FileActionModified event. (to discuss see #75).
package notify
var defaultTree = newTree()
// Watch sets up a watchpoint on path listening for events given by the events
// argument.
//
// File or directory given by the path must exist, otherwise Watch will fail
// with non-nil error. Notify resolves, for its internal purpose, any symlinks
// the provided path may contain, so it may fail if the symlinks form a cycle.
// It does so, since not all watcher implementations treat passed paths as-is.
// E.g. FSEvents reports a real path for every event, setting a watchpoint
// on /tmp will report events with paths rooted at /private/tmp etc.
//
// The c almost always is a buffered channel. Watch will not block sending to c
// - the caller must ensure that c has sufficient buffer space to keep up with
// the expected event rate.
//
// It is allowed to pass the same channel multiple times with different event
// list or different paths. Calling Watch with different event lists for a single
// watchpoint expands its event set. The only way to shrink it, is to call
// Stop on its channel.
//
// Calling Watch with empty event list does expand nor shrink watchpoint's event
// set. If c is the first channel to listen for events on the given path, Watch
// will seamlessly create a watch on the filesystem.
//
// Notify dispatches copies of single filesystem event to all channels registered
// for each path. If a single filesystem event contains multiple coalesced events,
// each of them is dispatched separately. E.g. the following filesystem change:
//
// ~ $ echo Hello > Notify.txt
//
// dispatches two events - notify.Create and notify.Write. However, it may depend
// on the underlying watcher implementation whether OS reports both of them.
//
// Windows and recursive watches
//
// If a directory which path was used to create recursive watch under Windows
// gets deleted, the OS will not report such event. It is advised to keep in
// mind this limitation while setting recursive watchpoints for your application,
// e.g. use persistant paths like %userprofile% or watch additionally parent
// directory of a recursive watchpoint in order to receive delete events for it.
func Watch(path string, c chan<- EventInfo, events ...Event) error {
return defaultTree.Watch(path, c, events...)
}
// Stop removes all watchpoints registered for c. All underlying watches are
// also removed, for which c was the last channel listening for events.
//
// Stop does not close c. When Stop returns, it is guranteed that c will
// receive no more signals.
func Stop(c chan<- EventInfo) {
defaultTree.Stop(c)
}

@ -0,0 +1,22 @@
// 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
const buffer = 128
type tree interface {
Watch(string, chan<- EventInfo, ...Event) error
Stop(chan<- EventInfo)
Close() error
}
func newTree() tree {
c := make(chan EventInfo, buffer)
w := newWatcher(c)
if rw, ok := w.(recursiveWatcher); ok {
return newRecursiveTree(rw, c)
}
return newNonrecursiveTree(w, c, make(chan EventInfo, buffer))
}

@ -0,0 +1,292 @@
// 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"
// nonrecursiveTree TODO(rjeczalik)
type nonrecursiveTree struct {
rw sync.RWMutex // protects root
root root
w watcher
c chan EventInfo
rec chan EventInfo
}
// newNonrecursiveTree TODO(rjeczalik)
func newNonrecursiveTree(w watcher, c, rec chan EventInfo) *nonrecursiveTree {
if rec == nil {
rec = make(chan EventInfo, buffer)
}
t := &nonrecursiveTree{
root: root{nd: newnode("")},
w: w,
c: c,
rec: rec,
}
go t.dispatch(c)
go t.internal(rec)
return t
}
// dispatch TODO(rjeczalik)
func (t *nonrecursiveTree) dispatch(c <-chan EventInfo) {
for ei := range c {
dbgprintf("dispatching %v on %q", ei.Event(), ei.Path())
go func(ei EventInfo) {
var nd node
var isrec bool
dir, base := split(ei.Path())
fn := func(it node, isbase bool) error {
isrec = isrec || it.Watch.IsRecursive()
if isbase {
nd = it
} else {
it.Watch.Dispatch(ei, recursive)
}
return nil
}
t.rw.RLock()
// Notify recursive watchpoints found on the path.
if err := t.root.WalkPath(dir, fn); err != nil {
dbgprint("dispatch did not reach leaf:", err)
t.rw.RUnlock()
return
}
// Notify parent watchpoint.
nd.Watch.Dispatch(ei, 0)
isrec = isrec || nd.Watch.IsRecursive()
// If leaf watchpoint exists, notify it.
if nd, ok := nd.Child[base]; ok {
isrec = isrec || nd.Watch.IsRecursive()
nd.Watch.Dispatch(ei, 0)
}
t.rw.RUnlock()
// If the event describes newly leaf directory created within
if !isrec || ei.Event() != Create {
return
}
if ok, err := ei.(isDirer).isDir(); !ok || err != nil {
return
}
t.rec <- ei
}(ei)
}
}
// internal TODO(rjeczalik)
func (t *nonrecursiveTree) internal(rec <-chan EventInfo) {
for ei := range rec {
var nd node
var eset = internal
t.rw.Lock()
t.root.WalkPath(ei.Path(), func(it node, _ bool) error {
if e := it.Watch[t.rec]; e != 0 && e > eset {
eset = e
}
nd = it
return nil
})
if eset == internal {
t.rw.Unlock()
continue
}
err := nd.Add(ei.Path()).AddDir(t.recFunc(eset))
t.rw.Unlock()
if err != nil {
dbgprintf("internal(%p) error: %v", rec, err)
}
}
}
// watchAdd TODO(rjeczalik)
func (t *nonrecursiveTree) watchAdd(nd node, c chan<- EventInfo, e Event) eventDiff {
if e&recursive != 0 {
diff := nd.Watch.Add(t.rec, e|Create|omit)
nd.Watch.Add(c, e)
return diff
}
return nd.Watch.Add(c, e)
}
// watchDelMin TODO(rjeczalik)
func (t *nonrecursiveTree) watchDelMin(min Event, nd node, c chan<- EventInfo, e Event) eventDiff {
old, ok := nd.Watch[t.rec]
if ok {
nd.Watch[t.rec] = min
}
diff := nd.Watch.Del(c, e)
if ok {
switch old &^= diff[0] &^ diff[1]; {
case old|internal == internal:
delete(nd.Watch, t.rec)
if set, ok := nd.Watch[nil]; ok && len(nd.Watch) == 1 && set == 0 {
delete(nd.Watch, nil)
}
default:
nd.Watch.Add(t.rec, old|Create)
switch {
case diff == none:
case diff[1]|Create == diff[0]:
diff = none
default:
diff[1] |= Create
}
}
}
return diff
}
// watchDel TODO(rjeczalik)
func (t *nonrecursiveTree) watchDel(nd node, c chan<- EventInfo, e Event) eventDiff {
return t.watchDelMin(0, nd, c, e)
}
// Watch TODO(rjeczalik)
func (t *nonrecursiveTree) 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
}
eset := joinevents(events)
t.rw.Lock()
defer t.rw.Unlock()
nd := t.root.Add(path)
if isrec {
return t.watchrec(nd, c, eset|recursive)
}
return t.watch(nd, c, eset)
}
func (t *nonrecursiveTree) watch(nd node, c chan<- EventInfo, e Event) (err error) {
diff := nd.Watch.Add(c, e)
switch {
case diff == none:
return nil
case diff[1] == 0:
// TODO(rjeczalik): cleanup this panic after implementation is stable
panic("eset is empty: " + nd.Name)
case diff[0] == 0:
err = t.w.Watch(nd.Name, diff[1])
default:
err = t.w.Rewatch(nd.Name, diff[0], diff[1])
}
if err != nil {
nd.Watch.Del(c, diff.Event())
return err
}
return nil
}
func (t *nonrecursiveTree) recFunc(e Event) walkFunc {
return func(nd node) error {
switch diff := nd.Watch.Add(t.rec, e|omit|Create); {
case diff == none:
case diff[1] == 0:
// TODO(rjeczalik): cleanup this panic after implementation is stable
panic("eset is empty: " + nd.Name)
case diff[0] == 0:
t.w.Watch(nd.Name, diff[1])
default:
t.w.Rewatch(nd.Name, diff[0], diff[1])
}
return nil
}
}
func (t *nonrecursiveTree) watchrec(nd node, c chan<- EventInfo, e Event) error {
var traverse func(walkFunc) error
// Non-recursive tree listens on Create event for every recursive
// watchpoint in order to automagically set a watch for every
// created directory.
switch diff := nd.Watch.dryAdd(t.rec, e|Create); {
case diff == none:
t.watchAdd(nd, c, e)
nd.Watch.Add(t.rec, e|omit|Create)
return nil
case diff[1] == 0:
// TODO(rjeczalik): cleanup this panic after implementation is stable
panic("eset is empty: " + nd.Name)
case diff[0] == 0:
// TODO(rjeczalik): BFS into directories and skip subtree as soon as first
// recursive watchpoint is encountered.
traverse = nd.AddDir
default:
traverse = nd.Walk
}
// TODO(rjeczalik): account every path that failed to be (re)watched
// and retry.
if err := traverse(t.recFunc(e)); err != nil {
return err
}
t.watchAdd(nd, c, e)
return nil
}
type walkWatchpointFunc func(Event, node) error
func (t *nonrecursiveTree) walkWatchpoint(nd node, fn walkWatchpointFunc) error {
type minode struct {
min Event
nd node
}
mnd := minode{nd: nd}
stack := []minode{mnd}
Traverse:
for n := len(stack); n != 0; n = len(stack) {
mnd, stack = stack[n-1], stack[:n-1]
// There must be no recursive watchpoints if the node has no watchpoints
// itself (every node in subtree rooted at recursive watchpoints must
// have at least nil (total) and t.rec watchpoints).
if len(mnd.nd.Watch) != 0 {
switch err := fn(mnd.min, mnd.nd); err {
case nil:
case errSkip:
continue Traverse
default:
return err
}
}
for _, nd := range mnd.nd.Child {
stack = append(stack, minode{mnd.nd.Watch[t.rec], nd})
}
}
return nil
}
// Stop TODO(rjeczalik)
func (t *nonrecursiveTree) Stop(c chan<- EventInfo) {
fn := func(min Event, nd node) error {
// TODO(rjeczalik): aggregate watcher errors and retry; in worst case
// forward to the user.
switch diff := t.watchDelMin(min, nd, c, all); {
case diff == none:
return nil
case diff[1] == 0:
t.w.Unwatch(nd.Name)
default:
t.w.Rewatch(nd.Name, diff[0], diff[1])
}
return nil
}
t.rw.Lock()
err := t.walkWatchpoint(t.root.nd, fn) // TODO(rjeczalik): store max root per c
t.rw.Unlock()
dbgprintf("Stop(%p) error: %v\n", c, err)
}
// Close TODO(rjeczalik)
func (t *nonrecursiveTree) Close() error {
err := t.w.Close()
close(t.c)
return err
}

@ -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
}

@ -0,0 +1,150 @@
// 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"
"os"
"path/filepath"
"strings"
)
const all = ^Event(0)
const sep = string(os.PathSeparator)
var errDepth = errors.New("exceeded allowed iteration count (circular symlink?)")
func min(i, j int) int {
if i > j {
return j
}
return i
}
func max(i, j int) int {
if i < j {
return j
}
return i
}
// must panics if err is non-nil.
func must(err error) {
if err != nil {
panic(err)
}
}
// nonil gives first non-nil error from the given arguments.
func nonil(err ...error) error {
for _, err := range err {
if err != nil {
return err
}
}
return nil
}
func cleanpath(path string) (realpath string, isrec bool, err error) {
if strings.HasSuffix(path, "...") {
isrec = true
path = path[:len(path)-3]
}
if path, err = filepath.Abs(path); err != nil {
return "", false, err
}
if path, err = canonical(path); err != nil {
return "", false, err
}
return path, isrec, nil
}
// canonical resolves any symlink in the given path and returns it in a clean form.
// It expects the path to be absolute. It fails to resolve circular symlinks by
// maintaining a simple iteration limit.
func canonical(p string) (string, error) {
p, err := filepath.Abs(p)
if err != nil {
return "", err
}
for i, j, depth := 1, 0, 1; i < len(p); i, depth = i+1, depth+1 {
if depth > 128 {
return "", &os.PathError{Op: "canonical", Path: p, Err: errDepth}
}
if j = strings.IndexRune(p[i:], '/'); j == -1 {
j, i = i, len(p)
} else {
j, i = i, i+j
}
fi, err := os.Lstat(p[:i])
if err != nil {
return "", err
}
if fi.Mode()&os.ModeSymlink == os.ModeSymlink {
s, err := os.Readlink(p[:i])
if err != nil {
return "", err
}
if filepath.IsAbs(s) {
p = "/" + s + p[i:]
} else {
p = p[:j] + s + p[i:]
}
i = 1 // no guarantee s is canonical, start all over
}
}
return filepath.Clean(p), nil
}
func joinevents(events []Event) (e Event) {
if len(events) == 0 {
e = All
} else {
for _, event := range events {
e |= event
}
}
return
}
func split(s string) (string, string) {
if i := lastIndexSep(s); i != -1 {
return s[:i], s[i+1:]
}
return "", s
}
func base(s string) string {
if i := lastIndexSep(s); i != -1 {
return s[i+1:]
}
return s
}
func indexbase(root, name string) int {
if n, m := len(root), len(name); m >= n && name[:n] == root &&
(n == m || name[n] == os.PathSeparator) {
return min(n+1, m)
}
return -1
}
func indexSep(s string) int {
for i := 0; i < len(s); i++ {
if s[i] == os.PathSeparator {
return i
}
}
return -1
}
func lastIndexSep(s string) int {
for i := len(s) - 1; i >= 0; i-- {
if s[i] == os.PathSeparator {
return i
}
}
return -1
}

@ -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
}

@ -0,0 +1,170 @@
// 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.
// +build solaris
package notify
import (
"fmt"
"os"
"syscall"
)
// newTrigger returns implementation of trigger.
func newTrigger(pthLkp map[string]*watched) trigger {
return &fen{
pthLkp: pthLkp,
cf: newCfen(),
}
}
// fen is a structure implementing trigger for FEN.
type fen struct {
// p is a FEN port identifier
p int
// pthLkp is a structure mapping monitored files/dir with data about them,
// shared with parent trg structure
pthLkp map[string]*watched
// cf wraps C operations for FEN
cf cfen
}
// watched is a data structure representing watched file/directory.
type watched struct {
// p is a path to watched file/directory
p string
// fi provides information about watched file/dir
fi os.FileInfo
// eDir represents events watched directly
eDir Event
// eNonDir represents events watched indirectly
eNonDir Event
}
// Stop implements trigger.
func (f *fen) Stop() error {
return f.cf.port_alert(f.p)
}
// Close implements trigger.
func (f *fen) Close() (err error) {
return syscall.Close(f.p)
}
// NewWatched implements trigger.
func (*fen) NewWatched(p string, fi os.FileInfo) (*watched, error) {
return &watched{p: p, fi: fi}, nil
}
// Record implements trigger.
func (f *fen) Record(w *watched) {
f.pthLkp[w.p] = w
}
// Del implements trigger.
func (f *fen) Del(w *watched) {
delete(f.pthLkp, w.p)
}
func inter2pe(n interface{}) PortEvent {
pe, ok := n.(PortEvent)
if !ok {
panic(fmt.Sprintf("fen: type should be PortEvent, %T instead", n))
}
return pe
}
// Watched implements trigger.
func (f *fen) Watched(n interface{}) (*watched, int64, error) {
pe := inter2pe(n)
fo, ok := pe.PortevObject.(*FileObj)
if !ok || fo == nil {
panic(fmt.Sprintf("fen: type should be *FileObj, %T instead", fo))
}
w, ok := f.pthLkp[fo.Name]
if !ok {
return nil, 0, errNotWatched
}
return w, int64(pe.PortevEvents), nil
}
// init initializes FEN.
func (f *fen) Init() (err error) {
f.p, err = f.cf.port_create()
return
}
func fi2fo(fi os.FileInfo, p string) FileObj {
st, ok := fi.Sys().(*syscall.Stat_t)
if !ok {
panic(fmt.Sprintf("fen: type should be *syscall.Stat_t, %T instead", st))
}
return FileObj{Name: p, Atim: st.Atim, Mtim: st.Mtim, Ctim: st.Ctim}
}
// Unwatch implements trigger.
func (f *fen) Unwatch(w *watched) error {
return f.cf.port_dissociate(f.p, FileObj{Name: w.p})
}
// Watch implements trigger.
func (f *fen) Watch(fi os.FileInfo, w *watched, e int64) error {
return f.cf.port_associate(f.p, fi2fo(fi, w.p), int(e))
}
// Wait implements trigger.
func (f *fen) Wait() (interface{}, error) {
var (
pe PortEvent
err error
)
err = f.cf.port_get(f.p, &pe)
return pe, err
}
// IsStop implements trigger.
func (f *fen) IsStop(n interface{}, err error) bool {
return err == syscall.EBADF || inter2pe(n).PortevSource == srcAlert
}
func init() {
encode = func(e Event) (o int64) {
// Create event is not supported by FEN. Instead FileModified event will
// be registered. If this event will be reported on dir which is to be
// monitored for Create, dir will be rescanned and Create events will
// be generated and returned for new files. In case of files,
// if not requested FileModified event is reported, it will be ignored.
if e&Create != 0 {
o = (o &^ int64(Create)) | int64(FileModified)
}
if e&Write != 0 {
o = (o &^ int64(Write)) | int64(FileModified)
}
// Following events are 'exception events' and as such cannot be requested
// explicitly for monitoring or filtered out. If the will be reported
// by FEN and not subscribed with by user, they will be filtered out by
// watcher's logic.
o &= int64(^Rename & ^Remove &^ FileDelete &^ FileRenameTo &^
FileRenameFrom &^ Unmounted &^ MountedOver)
return
}
nat2not = map[Event]Event{
FileModified: Write,
FileRenameFrom: Rename,
FileDelete: Remove,
FileAccess: Event(0),
FileAttrib: Event(0),
FileRenameTo: Event(0),
FileTrunc: Event(0),
FileNoFollow: Event(0),
Unmounted: Event(0),
MountedOver: Event(0),
}
not2nat = map[Event]Event{
Write: FileModified,
Rename: FileRenameFrom,
Remove: FileDelete,
}
}

@ -0,0 +1,141 @@
// 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.
// +build solaris
package notify
// #include <port.h>
// #include <stdio.h>
// #include <stdlib.h>
// struct file_obj* newFo() { return (struct file_obj*) malloc(sizeof(struct file_obj)); }
// port_event_t* newPe() { return (port_event_t*) malloc(sizeof(port_event_t)); }
// uintptr_t conv(struct file_obj* fo) { return (uintptr_t) fo; }
// struct file_obj* dconv(uintptr_t fo) { return (struct file_obj*) fo; }
import "C"
import (
"syscall"
"unsafe"
)
const (
fileAccess = Event(C.FILE_ACCESS)
fileModified = Event(C.FILE_MODIFIED)
fileAttrib = Event(C.FILE_ATTRIB)
fileDelete = Event(C.FILE_DELETE)
fileRenameTo = Event(C.FILE_RENAME_TO)
fileRenameFrom = Event(C.FILE_RENAME_FROM)
fileTrunc = Event(C.FILE_TRUNC)
fileNoFollow = Event(C.FILE_NOFOLLOW)
unmounted = Event(C.UNMOUNTED)
mountedOver = Event(C.MOUNTEDOVER)
)
// PortEvent is a notify's equivalent of port_event_t.
type PortEvent struct {
PortevEvents int // PortevEvents is an equivalent of portev_events.
PortevSource uint8 // PortevSource is an equivalent of portev_source.
PortevPad uint8 // Portevpad is an equivalent of portev_pad.
PortevObject interface{} // PortevObject is an equivalent of portev_object.
PortevUser uintptr // PortevUser is an equivalent of portev_user.
}
// FileObj is a notify's equivalent of file_obj.
type FileObj struct {
Atim syscall.Timespec // Atim is an equivalent of fo_atime.
Mtim syscall.Timespec // Mtim is an equivalent of fo_mtime.
Ctim syscall.Timespec // Ctim is an equivalent of fo_ctime.
Pad [3]uintptr // Pad is an equivalent of fo_pad.
Name string // Name is an equivalent of fo_name.
}
type cfen struct {
p2pe map[string]*C.port_event_t
p2fo map[string]*C.struct_file_obj
}
func newCfen() cfen {
return cfen{
p2pe: make(map[string]*C.port_event_t),
p2fo: make(map[string]*C.struct_file_obj),
}
}
func unix2C(sec int64, nsec int64) (C.time_t, C.long) {
return C.time_t(sec), C.long(nsec)
}
func (c *cfen) port_associate(p int, fo FileObj, e int) (err error) {
cfo := C.newFo()
cfo.fo_atime.tv_sec, cfo.fo_atime.tv_nsec = unix2C(fo.Atim.Unix())
cfo.fo_mtime.tv_sec, cfo.fo_mtime.tv_nsec = unix2C(fo.Mtim.Unix())
cfo.fo_ctime.tv_sec, cfo.fo_ctime.tv_nsec = unix2C(fo.Ctim.Unix())
cfo.fo_name = C.CString(fo.Name)
c.p2fo[fo.Name] = cfo
_, err = C.port_associate(C.int(p), srcFile, C.conv(cfo), C.int(e), nil)
return
}
func (c *cfen) port_dissociate(port int, fo FileObj) (err error) {
cfo, ok := c.p2fo[fo.Name]
if !ok {
return errNotWatched
}
_, err = C.port_dissociate(C.int(port), srcFile, C.conv(cfo))
C.free(unsafe.Pointer(cfo.fo_name))
C.free(unsafe.Pointer(cfo))
delete(c.p2fo, fo.Name)
return
}
const srcAlert = C.PORT_SOURCE_ALERT
const srcFile = C.PORT_SOURCE_FILE
const alertSet = C.PORT_ALERT_SET
func cfo2fo(cfo *C.struct_file_obj) *FileObj {
// Currently remaining attributes are not used.
if cfo == nil {
return nil
}
var fo FileObj
fo.Name = C.GoString(cfo.fo_name)
return &fo
}
func (c *cfen) port_get(port int, pe *PortEvent) (err error) {
cpe := C.newPe()
if _, err = C.port_get(C.int(port), cpe, nil); err != nil {
C.free(unsafe.Pointer(cpe))
return
}
pe.PortevEvents, pe.PortevSource, pe.PortevPad =
int(cpe.portev_events), uint8(cpe.portev_source), uint8(cpe.portev_pad)
pe.PortevObject = cfo2fo(C.dconv(cpe.portev_object))
pe.PortevUser = uintptr(cpe.portev_user)
C.free(unsafe.Pointer(cpe))
return
}
func (c *cfen) port_create() (int, error) {
p, err := C.port_create()
return int(p), err
}
func (c *cfen) port_alert(p int) (err error) {
_, err = C.port_alert(C.int(p), alertSet, C.int(666), nil)
return
}
func (c *cfen) free() {
for i := range c.p2fo {
C.free(unsafe.Pointer(c.p2fo[i].fo_name))
C.free(unsafe.Pointer(c.p2fo[i]))
}
for i := range c.p2pe {
C.free(unsafe.Pointer(c.p2pe[i]))
}
c.p2fo = make(map[string]*C.struct_file_obj)
c.p2pe = make(map[string]*C.port_event_t)
}

@ -0,0 +1,319 @@
// 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.
// +build darwin,!kqueue
package notify
import (
"errors"
"strings"
"sync/atomic"
)
// TODO(rjeczalik): get rid of calls to canonical, it's tree responsibility
const (
failure = uint32(FSEventsMustScanSubDirs | FSEventsUserDropped | FSEventsKernelDropped)
filter = uint32(FSEventsCreated | FSEventsRemoved | FSEventsRenamed |
FSEventsModified | FSEventsInodeMetaMod)
)
// FSEvent represents single file event. It is created out of values passed by
// FSEvents to FSEventStreamCallback function.
type FSEvent struct {
Path string // real path of the file or directory
ID uint64 // ID of the event (FSEventStreamEventId)
Flags uint32 // joint FSEvents* flags (FSEventStreamEventFlags)
}
// splitflags separates event flags from single set into slice of flags.
func splitflags(set uint32) (e []uint32) {
for i := uint32(1); set != 0; i, set = i<<1, set>>1 {
if (set & 1) != 0 {
e = append(e, i)
}
}
return
}
// watch represents a filesystem watchpoint. It is a higher level abstraction
// over FSEvents' stream, which implements filtering of file events based
// on path and event set. It emulates non-recursive watch-point by filtering out
// events which paths are more than 1 level deeper than the watched path.
type watch struct {
// prev stores last event set per path in order to filter out old flags
// for new events, which appratenly FSEvents likes to retain. It's a disgusting
// hack, it should be researched how to get rid of it.
prev map[string]uint32
c chan<- EventInfo
stream *stream
path string
events uint32
isrec int32
flushed bool
}
// Example format:
//
// ~ $ (trigger command) # (event set) -> (effective event set)
//
// Heuristics:
//
// 1. Create event is removed when it was present in previous event set.
// Example:
//
// ~ $ echo > file # Create|Write -> Create|Write
// ~ $ echo > file # Create|Write|InodeMetaMod -> Write|InodeMetaMod
//
// 2. Remove event is removed if it was present in previouse event set.
// Example:
//
// ~ $ touch file # Create -> Create
// ~ $ rm file # Create|Remove -> Remove
// ~ $ touch file # Create|Remove -> Create
//
// 3. Write event is removed if not followed by InodeMetaMod on existing
// file. Example:
//
// ~ $ echo > file # Create|Write -> Create|Write
// ~ $ chmod +x file # Create|Write|ChangeOwner -> ChangeOwner
//
// 4. Write&InodeMetaMod is removed when effective event set contain Remove event.
// Example:
//
// ~ $ echo > file # Write|InodeMetaMod -> Write|InodeMetaMod
// ~ $ rm file # Remove|Write|InodeMetaMod -> Remove
//
func (w *watch) strip(base string, set uint32) uint32 {
const (
write = FSEventsModified | FSEventsInodeMetaMod
both = FSEventsCreated | FSEventsRemoved
)
switch w.prev[base] {
case FSEventsCreated:
set &^= FSEventsCreated
if set&FSEventsRemoved != 0 {
w.prev[base] = FSEventsRemoved
set &^= write
}
case FSEventsRemoved:
set &^= FSEventsRemoved
if set&FSEventsCreated != 0 {
w.prev[base] = FSEventsCreated
}
default:
switch set & both {
case FSEventsCreated:
w.prev[base] = FSEventsCreated
case FSEventsRemoved:
w.prev[base] = FSEventsRemoved
set &^= write
}
}
dbgprintf("split()=%v\n", Event(set))
return set
}
// Dispatch is a stream function which forwards given file events for the watched
// path to underlying FileInfo channel.
func (w *watch) Dispatch(ev []FSEvent) {
events := atomic.LoadUint32(&w.events)
isrec := (atomic.LoadInt32(&w.isrec) == 1)
for i := range ev {
if ev[i].Flags&FSEventsHistoryDone != 0 {
w.flushed = true
continue
}
if !w.flushed {
continue
}
dbgprintf("%v (0x%x) (%s, i=%d, ID=%d, len=%d)\n", Event(ev[i].Flags),
ev[i].Flags, ev[i].Path, i, ev[i].ID, len(ev))
if ev[i].Flags&failure != 0 {
// TODO(rjeczalik): missing error handling
panic("unhandled error: " + Event(ev[i].Flags).String())
}
if !strings.HasPrefix(ev[i].Path, w.path) {
continue
}
n := len(w.path)
base := ""
if len(ev[i].Path) > n {
if ev[i].Path[n] != '/' {
continue
}
base = ev[i].Path[n+1:]
if !isrec && strings.IndexByte(base, '/') != -1 {
continue
}
}
// TODO(rjeczalik): get diff only from filtered events?
e := w.strip(string(base), ev[i].Flags) & events
if e == 0 {
continue
}
for _, e := range splitflags(e) {
dbgprintf("%d: single event: %v", ev[i].ID, Event(e))
w.c <- &event{
fse: ev[i],
event: Event(e),
}
}
}
}
// Stop closes underlying FSEvents stream and stops dispatching events.
func (w *watch) Stop() {
w.stream.Stop()
// TODO(rjeczalik): make (*stream).Stop flush synchronously undelivered events,
// so the following hack can be removed. It should flush all the streams
// concurrently as we care not to block too much here.
atomic.StoreUint32(&w.events, 0)
atomic.StoreInt32(&w.isrec, 0)
}
// fsevents implements Watcher and RecursiveWatcher interfaces backed by FSEvents
// framework.
type fsevents struct {
watches map[string]*watch
c chan<- EventInfo
}
func newWatcher(c chan<- EventInfo) watcher {
return &fsevents{
watches: make(map[string]*watch),
c: c,
}
}
func (fse *fsevents) watch(path string, event Event, isrec int32) (err error) {
if path, err = canonical(path); err != nil {
return err
}
if _, ok := fse.watches[path]; ok {
return errAlreadyWatched
}
w := &watch{
prev: make(map[string]uint32),
c: fse.c,
path: path,
events: uint32(event),
isrec: isrec,
}
w.stream = newStream(path, w.Dispatch)
if err = w.stream.Start(); err != nil {
return err
}
fse.watches[path] = w
return nil
}
func (fse *fsevents) unwatch(path string) (err error) {
if path, err = canonical(path); err != nil {
return
}
w, ok := fse.watches[path]
if !ok {
return errNotWatched
}
w.stream.Stop()
delete(fse.watches, path)
return nil
}
// Watch implements Watcher interface. It fails with non-nil error when setting
// the watch-point by FSEvents fails or with errAlreadyWatched error when
// the given path is already watched.
func (fse *fsevents) Watch(path string, event Event) error {
return fse.watch(path, event, 0)
}
// Unwatch implements Watcher interface. It fails with errNotWatched when
// the given path is not being watched.
func (fse *fsevents) Unwatch(path string) error {
return fse.unwatch(path)
}
// Rewatch implements Watcher interface. It fails with errNotWatched when
// the given path is not being watched or with errInvalidEventSet when oldevent
// does not match event set the watch-point currently holds.
func (fse *fsevents) Rewatch(path string, oldevent, newevent Event) error {
w, ok := fse.watches[path]
if !ok {
return errNotWatched
}
if !atomic.CompareAndSwapUint32(&w.events, uint32(oldevent), uint32(newevent)) {
return errInvalidEventSet
}
atomic.StoreInt32(&w.isrec, 0)
return nil
}
// RecursiveWatch implements RecursiveWatcher interface. It fails with non-nil
// error when setting the watch-point by FSEvents fails or with errAlreadyWatched
// error when the given path is already watched.
func (fse *fsevents) RecursiveWatch(path string, event Event) error {
return fse.watch(path, event, 1)
}
// RecursiveUnwatch implements RecursiveWatcher interface. It fails with
// errNotWatched when the given path is not being watched.
//
// TODO(rjeczalik): fail if w.isrec == 0?
func (fse *fsevents) RecursiveUnwatch(path string) error {
return fse.unwatch(path)
}
// RecrusiveRewatch implements RecursiveWatcher interface. It fails:
//
// * with errNotWatched when the given path is not being watched
// * with errInvalidEventSet when oldevent does not match the current event set
// * with errAlreadyWatched when watch-point given by the oldpath was meant to
// be relocated to newpath, but the newpath is already watched
// * a non-nil error when setting the watch-point with FSEvents fails
//
// TODO(rjeczalik): Improve handling of watch-point relocation? See two TODOs
// that follows.
func (fse *fsevents) RecursiveRewatch(oldpath, newpath string, oldevent, newevent Event) error {
switch [2]bool{oldpath == newpath, oldevent == newevent} {
case [2]bool{true, true}:
w, ok := fse.watches[oldpath]
if !ok {
return errNotWatched
}
atomic.StoreInt32(&w.isrec, 1)
return nil
case [2]bool{true, false}:
w, ok := fse.watches[oldpath]
if !ok {
return errNotWatched
}
if !atomic.CompareAndSwapUint32(&w.events, uint32(oldevent), uint32(newevent)) {
return errors.New("invalid event state diff")
}
atomic.StoreInt32(&w.isrec, 1)
return nil
default:
// TODO(rjeczalik): rewatch newpath only if exists?
// TODO(rjeczalik): migrate w.prev to new watch?
if _, ok := fse.watches[newpath]; ok {
return errAlreadyWatched
}
if err := fse.Unwatch(oldpath); err != nil {
return err
}
// TODO(rjeczalik): revert unwatch if watch fails?
return fse.watch(newpath, newevent, 1)
}
}
// Close unwatches all watch-points.
func (fse *fsevents) Close() error {
for _, w := range fse.watches {
w.Stop()
}
fse.watches = nil
return nil
}

@ -0,0 +1,190 @@
// 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.
// +build darwin,!kqueue
package notify
/*
#include <CoreServices/CoreServices.h>
typedef void (*CFRunLoopPerformCallBack)(void*);
void gosource(void *);
void gostream(uintptr_t, uintptr_t, size_t, uintptr_t, uintptr_t, uintptr_t);
static FSEventStreamRef EventStreamCreate(FSEventStreamContext * context, uintptr_t info, CFArrayRef paths, FSEventStreamEventId since, CFTimeInterval latency, FSEventStreamCreateFlags flags) {
context->info = (void*) info;
return FSEventStreamCreate(NULL, (FSEventStreamCallback) gostream, context, paths, since, latency, flags);
}
#cgo LDFLAGS: -framework CoreServices
*/
import "C"
import (
"errors"
"os"
"sync"
"sync/atomic"
"time"
"unsafe"
)
var nilstream C.FSEventStreamRef
// Default arguments for FSEventStreamCreate function.
var (
latency C.CFTimeInterval
flags = C.FSEventStreamCreateFlags(C.kFSEventStreamCreateFlagFileEvents | C.kFSEventStreamCreateFlagNoDefer)
since = uint64(C.FSEventsGetCurrentEventId())
)
var runloop C.CFRunLoopRef // global runloop which all streams are registered with
var wg sync.WaitGroup // used to wait until the runloop starts
// source is used for synchronization purposes - it signals when runloop has
// started and is ready via the wg. It also serves purpose of a dummy source,
// thanks to it the runloop does not return as it also has at least one source
// registered.
var source = C.CFRunLoopSourceCreate(nil, 0, &C.CFRunLoopSourceContext{
perform: (C.CFRunLoopPerformCallBack)(C.gosource),
})
// Errors returned when FSEvents functions fail.
var (
errCreate = os.NewSyscallError("FSEventStreamCreate", errors.New("NULL"))
errStart = os.NewSyscallError("FSEventStreamStart", errors.New("false"))
)
// initializes the global runloop and ensures any created stream awaits its
// readiness.
func init() {
wg.Add(1)
go func() {
runloop = C.CFRunLoopGetCurrent()
C.CFRunLoopAddSource(runloop, source, C.kCFRunLoopDefaultMode)
C.CFRunLoopRun()
panic("runloop has just unexpectedly stopped")
}()
C.CFRunLoopSourceSignal(source)
}
//export gosource
func gosource(unsafe.Pointer) {
time.Sleep(time.Second)
wg.Done()
}
//export gostream
func gostream(_, info uintptr, n C.size_t, paths, flags, ids uintptr) {
const (
offchar = unsafe.Sizeof((*C.char)(nil))
offflag = unsafe.Sizeof(C.FSEventStreamEventFlags(0))
offid = unsafe.Sizeof(C.FSEventStreamEventId(0))
)
if n == 0 {
return
}
ev := make([]FSEvent, 0, int(n))
for i := uintptr(0); i < uintptr(n); i++ {
switch flags := *(*uint32)(unsafe.Pointer((flags + i*offflag))); {
case flags&uint32(FSEventsEventIdsWrapped) != 0:
atomic.StoreUint64(&since, uint64(C.FSEventsGetCurrentEventId()))
default:
ev = append(ev, FSEvent{
Path: C.GoString(*(**C.char)(unsafe.Pointer(paths + i*offchar))),
Flags: flags,
ID: *(*uint64)(unsafe.Pointer(ids + i*offid)),
})
}
}
streamFuncs.get(info)(ev)
}
// StreamFunc is a callback called when stream receives file events.
type streamFunc func([]FSEvent)
var streamFuncs = streamFuncRegistry{m: map[uintptr]streamFunc{}}
type streamFuncRegistry struct {
mu sync.Mutex
m map[uintptr]streamFunc
i uintptr
}
func (r *streamFuncRegistry) get(id uintptr) streamFunc {
r.mu.Lock()
defer r.mu.Unlock()
return r.m[id]
}
func (r *streamFuncRegistry) add(fn streamFunc) uintptr {
r.mu.Lock()
defer r.mu.Unlock()
r.i++
r.m[r.i] = fn
return r.i
}
func (r *streamFuncRegistry) delete(id uintptr) {
r.mu.Lock()
defer r.mu.Unlock()
delete(r.m, id)
}
// Stream represents single watch-point which listens for events scheduled by
// the global runloop.
type stream struct {
path string
ref C.FSEventStreamRef
info uintptr
}
// NewStream creates a stream for given path, listening for file events and
// calling fn upon receving any.
func newStream(path string, fn streamFunc) *stream {
return &stream{
path: path,
info: streamFuncs.add(fn),
}
}
// Start creates a FSEventStream for the given path and schedules it with
// global runloop. It's a nop if the stream was already started.
func (s *stream) Start() error {
if s.ref != nilstream {
return nil
}
wg.Wait()
p := C.CFStringCreateWithCStringNoCopy(nil, C.CString(s.path), C.kCFStringEncodingUTF8, nil)
path := C.CFArrayCreate(nil, (*unsafe.Pointer)(unsafe.Pointer(&p)), 1, nil)
ctx := C.FSEventStreamContext{}
ref := C.EventStreamCreate(&ctx, C.uintptr_t(s.info), path, C.FSEventStreamEventId(atomic.LoadUint64(&since)), latency, flags)
if ref == nilstream {
return errCreate
}
C.FSEventStreamScheduleWithRunLoop(ref, runloop, C.kCFRunLoopDefaultMode)
if C.FSEventStreamStart(ref) == C.Boolean(0) {
C.FSEventStreamInvalidate(ref)
return errStart
}
C.CFRunLoopWakeUp(runloop)
s.ref = ref
return nil
}
// Stop stops underlying FSEventStream and unregisters it from global runloop.
func (s *stream) Stop() {
if s.ref == nilstream {
return
}
wg.Wait()
C.FSEventStreamStop(s.ref)
C.FSEventStreamInvalidate(s.ref)
C.CFRunLoopWakeUp(runloop)
s.ref = nilstream
streamFuncs.delete(s.info)
}

@ -0,0 +1,396 @@
// 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.
// +build linux
package notify
import (
"bytes"
"errors"
"path/filepath"
"runtime"
"sync"
"sync/atomic"
"syscall"
"unsafe"
)
// eventBufferSize defines the size of the buffer given to read(2) function. One
// should not depend on this value, since it was arbitrary chosen and may be
// changed in the future.
const eventBufferSize = 64 * (syscall.SizeofInotifyEvent + syscall.PathMax + 1)
// consumersCount defines the number of consumers in producer-consumer based
// implementation. Each consumer is run in a separate goroutine and has read
// access to watched files map.
const consumersCount = 2
const invalidDescriptor = -1
// watched is a pair of file path and inotify mask used as a value in
// watched files map.
type watched struct {
path string
mask uint32
}
// inotify implements Watcher interface.
type inotify struct {
sync.RWMutex // protects inotify.m map
m map[int32]*watched // watch descriptor to watched object
fd int32 // inotify file descriptor
pipefd []int // pipe's read and write descriptors
epfd int // epoll descriptor
epes []syscall.EpollEvent // epoll events
buffer [eventBufferSize]byte // inotify event buffer
wg sync.WaitGroup // wait group used to close main loop
c chan<- EventInfo // event dispatcher channel
}
// NewWatcher creates new non-recursive inotify backed by inotify.
func newWatcher(c chan<- EventInfo) watcher {
i := &inotify{
m: make(map[int32]*watched),
fd: invalidDescriptor,
pipefd: []int{invalidDescriptor, invalidDescriptor},
epfd: invalidDescriptor,
epes: make([]syscall.EpollEvent, 0),
c: c,
}
runtime.SetFinalizer(i, func(i *inotify) {
i.epollclose()
if i.fd != invalidDescriptor {
syscall.Close(int(i.fd))
}
})
return i
}
// Watch implements notify.watcher interface.
func (i *inotify) Watch(path string, e Event) error {
return i.watch(path, e)
}
// Rewatch implements notify.watcher interface.
func (i *inotify) Rewatch(path string, _, newevent Event) error {
return i.watch(path, newevent)
}
// watch adds a new watcher to the set of watched objects or modifies the existing
// one. If called for the first time, this function initializes inotify filesystem
// monitor and starts producer-consumers goroutines.
func (i *inotify) watch(path string, e Event) (err error) {
if e&^(All|Event(syscall.IN_ALL_EVENTS)) != 0 {
return errors.New("notify: unknown event")
}
if err = i.lazyinit(); err != nil {
return
}
iwd, err := syscall.InotifyAddWatch(int(i.fd), path, encode(e))
if err != nil {
return
}
i.RLock()
wd := i.m[int32(iwd)]
i.RUnlock()
if wd == nil {
i.Lock()
if i.m[int32(iwd)] == nil {
i.m[int32(iwd)] = &watched{path: path, mask: uint32(e)}
}
i.Unlock()
} else {
i.Lock()
wd.mask = uint32(e)
i.Unlock()
}
return nil
}
// lazyinit sets up all required file descriptors and starts 1+consumersCount
// goroutines. The producer goroutine blocks until file-system notifications
// occur. Then, all events are read from system buffer and sent to consumer
// goroutines which construct valid notify events. This method uses
// Double-Checked Locking optimization.
func (i *inotify) lazyinit() error {
if atomic.LoadInt32(&i.fd) == invalidDescriptor {
i.Lock()
defer i.Unlock()
if atomic.LoadInt32(&i.fd) == invalidDescriptor {
fd, err := syscall.InotifyInit()
if err != nil {
return err
}
i.fd = int32(fd)
if err = i.epollinit(); err != nil {
_, _ = i.epollclose(), syscall.Close(int(fd)) // Ignore errors.
i.fd = invalidDescriptor
return err
}
esch := make(chan []*event)
go i.loop(esch)
i.wg.Add(consumersCount)
for n := 0; n < consumersCount; n++ {
go i.send(esch)
}
}
}
return nil
}
// epollinit opens an epoll file descriptor and creates a pipe which will be
// used to wake up the epoll_wait(2) function. Then, file descriptor associated
// with inotify event queue and the read end of the pipe are added to epoll set.
// Note that `fd` member must be set before this function is called.
func (i *inotify) epollinit() (err error) {
if i.epfd, err = syscall.EpollCreate1(0); err != nil {
return
}
if err = syscall.Pipe(i.pipefd); err != nil {
return
}
i.epes = []syscall.EpollEvent{
{Events: syscall.EPOLLIN, Fd: i.fd},
{Events: syscall.EPOLLIN, Fd: int32(i.pipefd[0])},
}
if err = syscall.EpollCtl(i.epfd, syscall.EPOLL_CTL_ADD, int(i.fd), &i.epes[0]); err != nil {
return
}
return syscall.EpollCtl(i.epfd, syscall.EPOLL_CTL_ADD, i.pipefd[0], &i.epes[1])
}
// epollclose closes the file descriptor created by the call to epoll_create(2)
// and two file descriptors opened by pipe(2) function.
func (i *inotify) epollclose() (err error) {
if i.epfd != invalidDescriptor {
if err = syscall.Close(i.epfd); err == nil {
i.epfd = invalidDescriptor
}
}
for n, fd := range i.pipefd {
if fd != invalidDescriptor {
switch e := syscall.Close(fd); {
case e != nil && err == nil:
err = e
case e == nil:
i.pipefd[n] = invalidDescriptor
}
}
}
return
}
// loop blocks until either inotify or pipe file descriptor is ready for I/O.
// All read operations triggered by filesystem notifications are forwarded to
// one of the event's consumers. If pipe fd became ready, loop function closes
// all file descriptors opened by lazyinit method and returns afterwards.
func (i *inotify) loop(esch chan<- []*event) {
epes := make([]syscall.EpollEvent, 1)
fd := atomic.LoadInt32(&i.fd)
for {
switch _, err := syscall.EpollWait(i.epfd, epes, -1); err {
case nil:
switch epes[0].Fd {
case fd:
esch <- i.read()
epes[0].Fd = 0
case int32(i.pipefd[0]):
i.Lock()
defer i.Unlock()
if err = syscall.Close(int(fd)); err != nil && err != syscall.EINTR {
panic("notify: close(2) error " + err.Error())
}
atomic.StoreInt32(&i.fd, invalidDescriptor)
if err = i.epollclose(); err != nil && err != syscall.EINTR {
panic("notify: epollclose error " + err.Error())
}
close(esch)
return
}
case syscall.EINTR:
continue
default: // We should never reach this line.
panic("notify: epoll_wait(2) error " + err.Error())
}
}
}
// read reads events from an inotify file descriptor. It does not handle errors
// returned from read(2) function since they are not critical to watcher logic.
func (i *inotify) read() (es []*event) {
n, err := syscall.Read(int(i.fd), i.buffer[:])
if err != nil || n < syscall.SizeofInotifyEvent {
return
}
var sys *syscall.InotifyEvent
nmin := n - syscall.SizeofInotifyEvent
for pos, path := 0, ""; pos <= nmin; {
sys = (*syscall.InotifyEvent)(unsafe.Pointer(&i.buffer[pos]))
pos += syscall.SizeofInotifyEvent
if path = ""; sys.Len > 0 {
endpos := pos + int(sys.Len)
path = string(bytes.TrimRight(i.buffer[pos:endpos], "\x00"))
pos = endpos
}
es = append(es, &event{
sys: syscall.InotifyEvent{
Wd: sys.Wd,
Mask: sys.Mask,
Cookie: sys.Cookie,
},
path: path,
})
}
return
}
// send is a consumer function which sends events to event dispatcher channel.
// It is run in a separate goroutine in order to not block loop method when
// possibly expensive write operations are performed on inotify map.
func (i *inotify) send(esch <-chan []*event) {
for es := range esch {
for _, e := range i.transform(es) {
if e != nil {
i.c <- e
}
}
}
i.wg.Done()
}
// transform prepares events read from inotify file descriptor for sending to
// user. It removes invalid events and these which are no longer present in
// inotify map. This method may also split one raw event into two different ones
// when system-dependent result is required.
func (i *inotify) transform(es []*event) []*event {
var multi []*event
i.RLock()
for idx, e := range es {
if e.sys.Mask&(syscall.IN_IGNORED|syscall.IN_Q_OVERFLOW) != 0 {
es[idx] = nil
continue
}
wd, ok := i.m[e.sys.Wd]
if !ok || e.sys.Mask&encode(Event(wd.mask)) == 0 {
es[idx] = nil
continue
}
if e.path == "" {
e.path = wd.path
} else {
e.path = filepath.Join(wd.path, e.path)
}
multi = append(multi, decode(Event(wd.mask), e))
if e.event == 0 {
es[idx] = nil
}
}
i.RUnlock()
es = append(es, multi...)
return es
}
// encode converts notify system-independent events to valid inotify mask
// which can be passed to inotify_add_watch(2) function.
func encode(e Event) uint32 {
if e&Create != 0 {
e = (e ^ Create) | InCreate | InMovedTo
}
if e&Remove != 0 {
e = (e ^ Remove) | InDelete | InDeleteSelf
}
if e&Write != 0 {
e = (e ^ Write) | InModify
}
if e&Rename != 0 {
e = (e ^ Rename) | InMovedFrom | InMoveSelf
}
return uint32(e)
}
// decode uses internally stored mask to distinguish whether system-independent
// or system-dependent event is requested. The first one is created by modifying
// `e` argument. decode method sets e.event value to 0 when an event should be
// skipped. System-dependent event is set as the function's return value which
// can be nil when the event should not be passed on.
func decode(mask Event, e *event) (syse *event) {
if sysmask := uint32(mask) & e.sys.Mask; sysmask != 0 {
syse = &event{sys: syscall.InotifyEvent{
Wd: e.sys.Wd,
Mask: e.sys.Mask,
Cookie: e.sys.Cookie,
}, event: Event(sysmask), path: e.path}
}
imask := encode(mask)
switch {
case mask&Create != 0 && imask&uint32(InCreate|InMovedTo)&e.sys.Mask != 0:
e.event = Create
case mask&Remove != 0 && imask&uint32(InDelete|InDeleteSelf)&e.sys.Mask != 0:
e.event = Remove
case mask&Write != 0 && imask&uint32(InModify)&e.sys.Mask != 0:
e.event = Write
case mask&Rename != 0 && imask&uint32(InMovedFrom|InMoveSelf)&e.sys.Mask != 0:
e.event = Rename
default:
e.event = 0
}
return
}
// Unwatch implements notify.watcher interface. It looks for watch descriptor
// related to registered path and if found, calls inotify_rm_watch(2) function.
// This method is allowed to return EINVAL error when concurrently requested to
// delete identical path.
func (i *inotify) Unwatch(path string) (err error) {
iwd := int32(invalidDescriptor)
i.RLock()
for iwdkey, wd := range i.m {
if wd.path == path {
iwd = iwdkey
break
}
}
i.RUnlock()
if iwd == invalidDescriptor {
return errors.New("notify: path " + path + " is already watched")
}
fd := atomic.LoadInt32(&i.fd)
if _, err = syscall.InotifyRmWatch(int(fd), uint32(iwd)); err != nil {
return
}
i.Lock()
delete(i.m, iwd)
i.Unlock()
return nil
}
// Close implements notify.watcher interface. It removes all existing watch
// descriptors and wakes up producer goroutine by sending data to the write end
// of the pipe. The function waits for a signal from producer which means that
// all operations on current monitoring instance are done.
func (i *inotify) Close() (err error) {
i.Lock()
if fd := atomic.LoadInt32(&i.fd); fd == invalidDescriptor {
i.Unlock()
return nil
}
for iwd := range i.m {
if _, e := syscall.InotifyRmWatch(int(i.fd), uint32(iwd)); e != nil && err == nil {
err = e
}
delete(i.m, iwd)
}
switch _, errwrite := syscall.Write(i.pipefd[1], []byte{0x00}); {
case errwrite != nil && err == nil:
err = errwrite
fallthrough
case errwrite != nil:
i.Unlock()
default:
i.Unlock()
i.wg.Wait()
}
return
}

@ -0,0 +1,192 @@
// 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.
// +build darwin,kqueue dragonfly freebsd netbsd openbsd
package notify
import (
"fmt"
"os"
"syscall"
)
// newTrigger returns implementation of trigger.
func newTrigger(pthLkp map[string]*watched) trigger {
return &kq{
pthLkp: pthLkp,
idLkp: make(map[int]*watched),
}
}
// kq is a structure implementing trigger for kqueue.
type kq struct {
// fd is a kqueue file descriptor
fd int
// pipefds are file descriptors used to stop `Kevent` call.
pipefds [2]int
// idLkp is a data structure mapping file descriptors with data about watching
// represented by them files/directories.
idLkp map[int]*watched
// pthLkp is a structure mapping monitored files/dir with data about them,
// shared with parent trg structure
pthLkp map[string]*watched
}
// watched is a data structure representing watched file/directory.
type watched struct {
// p is a path to watched file/directory.
p string
// fd is a file descriptor for watched file/directory.
fd int
// fi provides information about watched file/dir.
fi os.FileInfo
// eDir represents events watched directly.
eDir Event
// eNonDir represents events watched indirectly.
eNonDir Event
}
// Stop implements trigger.
func (k *kq) Stop() (err error) {
// trigger event used to interrupt Kevent call.
_, err = syscall.Write(k.pipefds[1], []byte{0x00})
return
}
// Close implements trigger.
func (k *kq) Close() error {
return syscall.Close(k.fd)
}
// NewWatched implements trigger.
func (*kq) NewWatched(p string, fi os.FileInfo) (*watched, error) {
fd, err := syscall.Open(p, syscall.O_NONBLOCK|syscall.O_RDONLY, 0)
if err != nil {
return nil, err
}
return &watched{fd: fd, p: p, fi: fi}, nil
}
// Record implements trigger.
func (k *kq) Record(w *watched) {
k.idLkp[w.fd], k.pthLkp[w.p] = w, w
}
// Del implements trigger.
func (k *kq) Del(w *watched) {
syscall.Close(w.fd)
delete(k.idLkp, w.fd)
delete(k.pthLkp, w.p)
}
func inter2kq(n interface{}) syscall.Kevent_t {
kq, ok := n.(syscall.Kevent_t)
if !ok {
panic(fmt.Sprintf("kqueue: type should be Kevent_t, %T instead", n))
}
return kq
}
// Init implements trigger.
func (k *kq) 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 nonil(err, k.Close())
}
var kevn [1]syscall.Kevent_t
syscall.SetKevent(&kevn[0], k.pipefds[0], syscall.EVFILT_READ, syscall.EV_ADD)
if _, err = syscall.Kevent(k.fd, kevn[:], nil, nil); err != nil {
return nonil(err, k.Close())
}
return
}
// 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 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
}
// 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
}
// Watched implements trigger.
func (k *kq) Watched(n interface{}) (*watched, int64, error) {
kevn, ok := n.(syscall.Kevent_t)
if !ok {
panic(fmt.Sprintf("kq: type should be syscall.Kevent_t, %T instead", kevn))
}
if _, ok = k.idLkp[int(kevn.Ident)]; !ok {
return nil, 0, errNotWatched
}
return k.idLkp[int(kevn.Ident)], int64(kevn.Fflags), nil
}
// IsStop implements trigger.
func (k *kq) IsStop(n interface{}, err error) bool {
return int(inter2kq(n).Ident) == k.pipefds[0]
}
func init() {
encode = func(e Event) (o int64) {
// Create event is not supported by kqueue. Instead NoteWrite event will
// be registered. If this event will be reported on dir which is to be
// monitored for Create, dir will be rescanned and Create events will
// be generated and returned for new files. In case of files,
// if not requested NoteRename event is reported, it will be ignored.
o = int64(e &^ Create)
if e&Write != 0 {
o = (o &^ int64(Write)) | int64(NoteWrite)
}
if e&Rename != 0 {
o = (o &^ int64(Rename)) | int64(NoteRename)
}
if e&Remove != 0 {
o = (o &^ int64(Remove)) | int64(NoteDelete)
}
return
}
nat2not = map[Event]Event{
NoteWrite: Write,
NoteRename: Rename,
NoteDelete: Remove,
NoteExtend: Event(0),
NoteAttrib: Event(0),
NoteRevoke: Event(0),
NoteLink: Event(0),
}
not2nat = map[Event]Event{
Write: NoteWrite,
Rename: NoteRename,
Remove: NoteDelete,
}
}

@ -0,0 +1,574 @@
// 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.
// +build windows
package notify
import (
"errors"
"runtime"
"sync"
"sync/atomic"
"syscall"
"unsafe"
)
// readBufferSize defines the size of an array in which read statuses are stored.
// The buffer have to be DWORD-aligned and, if notify is used in monitoring a
// directory over the network, its size must not be greater than 64KB. Each of
// watched directories uses its own buffer for storing events.
const readBufferSize = 4096
// Since all operations which go through the Windows completion routine are done
// asynchronously, filter may set one of the constants belor. They were defined
// in order to distinguish whether current folder should be re-registered in
// ReadDirectoryChangesW function or some control operations need to be executed.
const (
stateRewatch uint32 = 1 << (28 + iota)
stateUnwatch
stateCPClose
)
// Filter used in current implementation was split into four segments:
// - bits 0-11 store ReadDirectoryChangesW filters,
// - bits 12-19 store File notify actions,
// - bits 20-27 store notify specific events and flags,
// - bits 28-31 store states which are used in loop's FSM.
// Constants below are used as masks to retrieve only specific filter parts.
const (
onlyNotifyChanges uint32 = 0x00000FFF
onlyNGlobalEvents uint32 = 0x0FF00000
onlyMachineStates uint32 = 0xF0000000
)
// grip represents a single watched directory. It stores the data required by
// ReadDirectoryChangesW function. Only the filter, recursive, and handle members
// may by modified by watcher implementation. Rest of the them have to remain
// constant since they are used by Windows completion routine. This indicates that
// grip can be removed only when all operations on the file handle are finished.
type grip struct {
handle syscall.Handle
filter uint32
recursive bool
pathw []uint16
buffer [readBufferSize]byte
parent *watched
ovlapped *overlappedEx
}
// overlappedEx stores information used in asynchronous input and output.
// Additionally, overlappedEx contains a pointer to 'grip' item which is used in
// order to gather the structure in which the overlappedEx object was created.
type overlappedEx struct {
syscall.Overlapped
parent *grip
}
// newGrip creates a new file handle that can be used in overlapped operations.
// Then, the handle is associated with I/O completion port 'cph' and its value
// is stored in newly created 'grip' object.
func newGrip(cph syscall.Handle, parent *watched, filter uint32) (*grip, error) {
g := &grip{
handle: syscall.InvalidHandle,
filter: filter,
recursive: parent.recursive,
pathw: parent.pathw,
parent: parent,
ovlapped: &overlappedEx{},
}
if err := g.register(cph); err != nil {
return nil, err
}
g.ovlapped.parent = g
return g, nil
}
// NOTE : Thread safe
func (g *grip) register(cph syscall.Handle) (err error) {
if g.handle, err = syscall.CreateFile(
&g.pathw[0],
syscall.FILE_LIST_DIRECTORY,
syscall.FILE_SHARE_READ|syscall.FILE_SHARE_WRITE|syscall.FILE_SHARE_DELETE,
nil,
syscall.OPEN_EXISTING,
syscall.FILE_FLAG_BACKUP_SEMANTICS|syscall.FILE_FLAG_OVERLAPPED,
0,
); err != nil {
return
}
if _, err = syscall.CreateIoCompletionPort(g.handle, cph, 0, 0); err != nil {
syscall.CloseHandle(g.handle)
return
}
return g.readDirChanges()
}
// readDirChanges tells the system to store file change information in grip's
// buffer. Directory changes that occur between calls to this function are added
// to the buffer and then, returned with the next call.
func (g *grip) readDirChanges() error {
return syscall.ReadDirectoryChanges(
g.handle,
&g.buffer[0],
uint32(unsafe.Sizeof(g.buffer)),
g.recursive,
encode(g.filter),
nil,
(*syscall.Overlapped)(unsafe.Pointer(g.ovlapped)),
0,
)
}
// encode transforms a generic filter, which contains platform independent and
// implementation specific bit fields, to value that can be used as NotifyFilter
// parameter in ReadDirectoryChangesW function.
func encode(filter uint32) uint32 {
e := Event(filter & (onlyNGlobalEvents | onlyNotifyChanges))
if e&dirmarker != 0 {
return uint32(FileNotifyChangeDirName)
}
if e&Create != 0 {
e = (e ^ Create) | FileNotifyChangeFileName
}
if e&Remove != 0 {
e = (e ^ Remove) | FileNotifyChangeFileName
}
if e&Write != 0 {
e = (e ^ Write) | FileNotifyChangeAttributes | FileNotifyChangeSize |
FileNotifyChangeCreation | FileNotifyChangeSecurity
}
if e&Rename != 0 {
e = (e ^ Rename) | FileNotifyChangeFileName
}
return uint32(e)
}
// watched is made in order to check whether an action comes from a directory or
// file. This approach requires two file handlers per single monitored folder. The
// second grip handles actions which include creating or deleting a directory. If
// these processes are not monitored, only the first grip is created.
type watched struct {
filter uint32
recursive bool
count uint8
pathw []uint16
digrip [2]*grip
}
// newWatched creates a new watched instance. It splits the filter variable into
// two parts. The first part is responsible for watching all events which can be
// created for a file in watched directory structure and the second one watches
// only directory Create/Remove actions. If all operations succeed, the Create
// message is sent to I/O completion port queue for further processing.
func newWatched(cph syscall.Handle, filter uint32, recursive bool,
path string) (wd *watched, err error) {
wd = &watched{
filter: filter,
recursive: recursive,
}
if wd.pathw, err = syscall.UTF16FromString(path); err != nil {
return
}
if err = wd.recreate(cph); err != nil {
return
}
return wd, nil
}
// TODO : doc
func (wd *watched) recreate(cph syscall.Handle) (err error) {
filefilter := wd.filter &^ uint32(FileNotifyChangeDirName)
if err = wd.updateGrip(0, cph, filefilter == 0, filefilter); err != nil {
return
}
dirfilter := wd.filter & uint32(FileNotifyChangeDirName|Create|Remove)
if err = wd.updateGrip(1, cph, dirfilter == 0, wd.filter|uint32(dirmarker)); err != nil {
return
}
wd.filter &^= onlyMachineStates
return
}
// TODO : doc
func (wd *watched) updateGrip(idx int, cph syscall.Handle, reset bool,
newflag uint32) (err error) {
if reset {
wd.digrip[idx] = nil
} else {
if wd.digrip[idx] == nil {
if wd.digrip[idx], err = newGrip(cph, wd, newflag); err != nil {
wd.closeHandle()
return
}
} else {
wd.digrip[idx].filter = newflag
wd.digrip[idx].recursive = wd.recursive
if err = wd.digrip[idx].register(cph); err != nil {
wd.closeHandle()
return
}
}
wd.count++
}
return
}
// closeHandle closes handles that are stored in digrip array. Function always
// tries to close all of the handlers before it exits, even when there are errors
// returned from the operating system kernel.
func (wd *watched) closeHandle() (err error) {
for _, g := range wd.digrip {
if g != nil && g.handle != syscall.InvalidHandle {
switch suberr := syscall.CloseHandle(g.handle); {
case suberr == nil:
g.handle = syscall.InvalidHandle
case err == nil:
err = suberr
}
}
}
return
}
// watcher implements Watcher interface. It stores a set of watched directories.
// All operations which remove watched objects from map `m` must be performed in
// loop goroutine since these structures are used internally by operating system.
type readdcw struct {
sync.Mutex
m map[string]*watched
cph syscall.Handle
start bool
wg sync.WaitGroup
c chan<- EventInfo
}
// NewWatcher creates new non-recursive watcher backed by ReadDirectoryChangesW.
func newWatcher(c chan<- EventInfo) watcher {
r := &readdcw{
m: make(map[string]*watched),
cph: syscall.InvalidHandle,
c: c,
}
runtime.SetFinalizer(r, func(r *readdcw) {
if r.cph != syscall.InvalidHandle {
syscall.CloseHandle(r.cph)
}
})
return r
}
// Watch implements notify.Watcher interface.
func (r *readdcw) Watch(path string, event Event) error {
return r.watch(path, event, false)
}
// RecursiveWatch implements notify.RecursiveWatcher interface.
func (r *readdcw) RecursiveWatch(path string, event Event) error {
return r.watch(path, event, true)
}
// watch inserts a directory to the group of watched folders. If watched folder
// already exists, function tries to rewatch it with new filters(NOT VALID). Moreover,
// watch starts the main event loop goroutine when called for the first time.
func (r *readdcw) watch(path string, event Event, recursive bool) (err error) {
if event&^(All|fileNotifyChangeAll) != 0 {
return errors.New("notify: unknown event")
}
r.Lock()
wd, ok := r.m[path]
r.Unlock()
if !ok {
if err = r.lazyinit(); err != nil {
return
}
r.Lock()
if wd, ok = r.m[path]; ok {
r.Unlock()
return
}
if wd, err = newWatched(r.cph, uint32(event), recursive, path); err != nil {
r.Unlock()
return
}
r.m[path] = wd
r.Unlock()
}
return nil
}
// lazyinit creates an I/O completion port and starts the main event processing
// loop. This method uses Double-Checked Locking optimization.
func (r *readdcw) lazyinit() (err error) {
invalid := uintptr(syscall.InvalidHandle)
if atomic.LoadUintptr((*uintptr)(&r.cph)) == invalid {
r.Lock()
defer r.Unlock()
if atomic.LoadUintptr((*uintptr)(&r.cph)) == invalid {
cph := syscall.InvalidHandle
if cph, err = syscall.CreateIoCompletionPort(cph, 0, 0, 0); err != nil {
return
}
r.cph, r.start = cph, true
go r.loop()
}
}
return
}
// TODO(pknap) : doc
func (r *readdcw) loop() {
var n, key uint32
var overlapped *syscall.Overlapped
for {
err := syscall.GetQueuedCompletionStatus(r.cph, &n, &key, &overlapped, syscall.INFINITE)
if key == stateCPClose {
r.Lock()
handle := r.cph
r.cph = syscall.InvalidHandle
r.Unlock()
syscall.CloseHandle(handle)
r.wg.Done()
return
}
if overlapped == nil {
// TODO: check key == rewatch delete or 0(panic)
continue
}
overEx := (*overlappedEx)(unsafe.Pointer(overlapped))
if n == 0 {
r.loopstate(overEx)
} else {
r.loopevent(n, overEx)
if err = overEx.parent.readDirChanges(); err != nil {
// TODO: error handling
}
}
}
}
// TODO(pknap) : doc
func (r *readdcw) loopstate(overEx *overlappedEx) {
filter := atomic.LoadUint32(&overEx.parent.parent.filter)
if filter&onlyMachineStates == 0 {
return
}
if overEx.parent.parent.count--; overEx.parent.parent.count == 0 {
switch filter & onlyMachineStates {
case stateRewatch:
r.Lock()
overEx.parent.parent.recreate(r.cph)
r.Unlock()
case stateUnwatch:
r.Lock()
delete(r.m, syscall.UTF16ToString(overEx.parent.pathw))
r.Unlock()
case stateCPClose:
default:
panic(`notify: windows loopstate logic error`)
}
}
}
// TODO(pknap) : doc
func (r *readdcw) loopevent(n uint32, overEx *overlappedEx) {
events := []*event{}
var currOffset uint32
for {
raw := (*syscall.FileNotifyInformation)(unsafe.Pointer(&overEx.parent.buffer[currOffset]))
name := syscall.UTF16ToString((*[syscall.MAX_PATH]uint16)(unsafe.Pointer(&raw.FileName))[:raw.FileNameLength>>1])
events = append(events, &event{
pathw: overEx.parent.pathw,
filter: overEx.parent.filter,
action: raw.Action,
name: name,
})
if raw.NextEntryOffset == 0 {
break
}
if currOffset += raw.NextEntryOffset; currOffset >= n {
break
}
}
r.send(events)
}
// TODO(pknap) : doc
func (r *readdcw) send(es []*event) {
for _, e := range es {
var syse Event
if e.e, syse = decode(e.filter, e.action); e.e == 0 && syse == 0 {
continue
}
switch {
case e.action == syscall.FILE_ACTION_MODIFIED:
e.ftype = fTypeUnknown
case e.filter&uint32(dirmarker) != 0:
e.ftype = fTypeDirectory
default:
e.ftype = fTypeFile
}
switch {
case e.e == 0:
e.e = syse
case syse != 0:
r.c <- &event{
pathw: e.pathw,
name: e.name,
ftype: e.ftype,
action: e.action,
filter: e.filter,
e: syse,
}
}
r.c <- e
}
}
// Rewatch implements notify.Rewatcher interface.
func (r *readdcw) Rewatch(path string, oldevent, newevent Event) error {
return r.rewatch(path, uint32(oldevent), uint32(newevent), false)
}
// RecursiveRewatch implements notify.RecursiveRewatcher interface.
func (r *readdcw) RecursiveRewatch(oldpath, newpath string, oldevent,
newevent Event) error {
if oldpath != newpath {
if err := r.unwatch(oldpath); err != nil {
return err
}
return r.watch(newpath, newevent, true)
}
return r.rewatch(newpath, uint32(oldevent), uint32(newevent), true)
}
// TODO : (pknap) doc.
func (r *readdcw) rewatch(path string, oldevent, newevent uint32, recursive bool) (err error) {
if Event(newevent)&^(All|fileNotifyChangeAll) != 0 {
return errors.New("notify: unknown event")
}
var wd *watched
r.Lock()
if wd, err = r.nonStateWatched(path); err != nil {
r.Unlock()
return
}
if wd.filter&(onlyNotifyChanges|onlyNGlobalEvents) != oldevent {
panic(`notify: windows re-watcher logic error`)
}
wd.filter = stateRewatch | newevent
wd.recursive, recursive = recursive, wd.recursive
if err = wd.closeHandle(); err != nil {
wd.filter = oldevent
wd.recursive = recursive
r.Unlock()
return
}
r.Unlock()
return
}
// TODO : pknap
func (r *readdcw) nonStateWatched(path string) (wd *watched, err error) {
wd, ok := r.m[path]
if !ok || wd == nil {
err = errors.New(`notify: ` + path + ` path is unwatched`)
return
}
if filter := atomic.LoadUint32(&wd.filter); filter&onlyMachineStates != 0 {
err = errors.New(`notify: another re/unwatching operation in progress`)
return
}
return
}
// Unwatch implements notify.Watcher interface.
func (r *readdcw) Unwatch(path string) error {
return r.unwatch(path)
}
// RecursiveUnwatch implements notify.RecursiveWatcher interface.
func (r *readdcw) RecursiveUnwatch(path string) error {
return r.unwatch(path)
}
// TODO : pknap
func (r *readdcw) unwatch(path string) (err error) {
var wd *watched
r.Lock()
if wd, err = r.nonStateWatched(path); err != nil {
r.Unlock()
return
}
wd.filter |= stateUnwatch
if err = wd.closeHandle(); err != nil {
wd.filter &^= stateUnwatch
r.Unlock()
return
}
r.Unlock()
return
}
// Close resets the whole watcher object, closes all existing file descriptors,
// and sends stateCPClose state as completion key to the main watcher's loop.
func (r *readdcw) Close() (err error) {
r.Lock()
if !r.start {
r.Unlock()
return nil
}
for _, wd := range r.m {
wd.filter &^= onlyMachineStates
wd.filter |= stateCPClose
if e := wd.closeHandle(); e != nil && err == nil {
err = e
}
}
r.start = false
r.Unlock()
r.wg.Add(1)
if e := syscall.PostQueuedCompletionStatus(r.cph, 0, stateCPClose, nil); e != nil && err == nil {
return e
}
r.wg.Wait()
return
}
// decode creates a notify event from both non-raw filter and action which was
// returned from completion routine. Function may return Event(0) in case when
// filter was replaced by a new value which does not contain fields that are
// valid with passed action.
func decode(filter, action uint32) (Event, Event) {
switch action {
case syscall.FILE_ACTION_ADDED:
return gensys(filter, Create, FileActionAdded)
case syscall.FILE_ACTION_REMOVED:
return gensys(filter, Remove, FileActionRemoved)
case syscall.FILE_ACTION_MODIFIED:
return gensys(filter, Write, FileActionModified)
case syscall.FILE_ACTION_RENAMED_OLD_NAME:
return gensys(filter, Rename, FileActionRenamedOldName)
case syscall.FILE_ACTION_RENAMED_NEW_NAME:
return gensys(filter, Rename, FileActionRenamedNewName)
}
panic(`notify: cannot decode internal mask`)
}
// gensys decides whether the Windows action, system-independent event or both
// of them should be returned. Since the grip's filter may be atomically changed
// during watcher lifetime, it is possible that neither Windows nor notify masks
// are watched by the user when this function is called.
func gensys(filter uint32, ge, se Event) (gene, syse Event) {
isdir := filter&uint32(dirmarker) != 0
if isdir && filter&uint32(FileNotifyChangeDirName) != 0 ||
!isdir && filter&uint32(FileNotifyChangeFileName) != 0 ||
filter&uint32(fileNotifyChangeModified) != 0 {
syse = se
}
if filter&uint32(ge) != 0 {
gene = ge
}
return
}

@ -0,0 +1,23 @@
// 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.
// +build !darwin,!linux,!freebsd,!dragonfly,!netbsd,!openbsd,!windows
// +build !kqueue,!solaris
package notify
import "errors"
type stub struct{ error }
// newWatcher stub.
func newWatcher(chan<- EventInfo) watcher {
return stub{errors.New("notify: not implemented")}
}
// Following methods implement notify.watcher interface.
func (s stub) Watch(string, Event) error { return s }
func (s stub) Rewatch(string, Event, Event) error { return s }
func (s stub) Unwatch(string) (err error) { return s }
func (s stub) Close() error { return s }

@ -0,0 +1,438 @@
// 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.
// +build darwin,kqueue dragonfly freebsd netbsd openbsd solaris
// watcher_trigger is used for FEN and kqueue which behave similarly:
// only files and dirs can be watched directly, but not files inside dirs.
// As a result Create events have to be generated by implementation when
// after Write event is returned for watched dir, it is rescanned and Create
// event is returned for new files and these are automatically added
// to watchlist. In case of removal of watched directory, native system returns
// events for all files, but for Rename, they also need to be generated.
// As a result native system works as something like trigger for rescan,
// but contains additional data about dir in which changes occurred. For files
// detailed data is returned.
// Usage of watcher_trigger requires:
// - trigger implementation,
// - encode func,
// - not2nat, nat2not maps.
// Required manual operations on filesystem can lead to loss of precision.
package notify
import (
"os"
"path/filepath"
"strings"
"sync"
"syscall"
)
// trigger is to be implemented by platform implementation like FEN or kqueue.
type trigger interface {
// Close closes watcher's main native file descriptor.
Close() error
// Stop waiting for new events.
Stop() error
// Create new instance of watched.
NewWatched(string, os.FileInfo) (*watched, error)
// Record internally new *watched instance.
Record(*watched)
// Del removes internal copy of *watched instance.
Del(*watched)
// Watched returns *watched instance and native events for native type.
Watched(interface{}) (*watched, int64, error)
// Init initializes native watcher call.
Init() error
// Watch starts watching provided file/dir.
Watch(os.FileInfo, *watched, int64) error
// Unwatch stops watching provided file/dir.
Unwatch(*watched) error
// Wait for new events.
Wait() (interface{}, error)
// IsStop checks if Wait finished because of request watcher's stop.
IsStop(n interface{}, err error) bool
}
// encode Event to native representation. Implementation is to be provided by
// platform specific implementation.
var encode func(Event) int64
var (
// nat2not matches native events to notify's ones. To be initialized by
// platform dependent implementation.
nat2not map[Event]Event
// not2nat matches notify's events to native ones. To be initialized by
// platform dependent implementation.
not2nat map[Event]Event
)
// trg is a main structure implementing watcher.
type trg struct {
sync.Mutex
// s is a channel used to stop monitoring.
s chan struct{}
// c is a channel used to pass events further.
c chan<- EventInfo
// pthLkp is a data structure mapping file names with data about watching
// represented by them files/directories.
pthLkp map[string]*watched
// t is a platform dependent implementation of trigger.
t trigger
}
// newWatcher returns new watcher's implementation.
func newWatcher(c chan<- EventInfo) watcher {
t := &trg{
s: make(chan struct{}, 1),
pthLkp: make(map[string]*watched, 0),
c: c,
}
t.t = newTrigger(t.pthLkp)
if err := t.t.Init(); err != nil {
panic(err)
}
go t.monitor()
return t
}
// Close implements watcher.
func (t *trg) Close() (err error) {
t.Lock()
if err = t.t.Stop(); err != nil {
t.Unlock()
return
}
<-t.s
var e error
for _, w := range t.pthLkp {
if e = t.unwatch(w.p, w.fi); e != nil {
dbgprintf("trg: unwatch %q failed: %q\n", w.p, e)
err = nonil(err, e)
}
}
if e = t.t.Close(); e != nil {
dbgprintf("trg: closing native watch failed: %q\n", e)
err = nonil(err, e)
}
t.Unlock()
return
}
// send reported events one by one through chan.
func (t *trg) send(evn []event) {
for i := range evn {
t.c <- &evn[i]
}
}
// singlewatch starts to watch given p file/directory.
func (t *trg) singlewatch(p string, e Event, direct mode, fi os.FileInfo) (err error) {
w, ok := t.pthLkp[p]
if !ok {
if w, err = t.t.NewWatched(p, fi); err != nil {
return
}
}
switch direct {
case dir:
w.eDir |= e
case ndir:
w.eNonDir |= e
case both:
w.eDir |= e
w.eNonDir |= e
}
var ee int64
// Native Write event is added to wait for Create events (Write event on
// directory triggers it's rescan).
if e&Create != 0 && fi.IsDir() {
ee = int64(not2nat[Write])
}
if err = t.t.Watch(fi, w, encode(w.eDir|w.eNonDir)|ee); err != nil {
return
}
if !ok {
t.t.Record(w)
return nil
}
return errAlreadyWatched
}
// decode converts event received from native to notify.Event
// representation taking into account requested events (w).
func decode(o int64, w Event) (e Event) {
for f, n := range nat2not {
if o&int64(f) != 0 {
if w&f != 0 {
e |= f
}
if w&n != 0 {
e |= n
}
}
}
return
}
func (t *trg) watch(p string, e Event, fi os.FileInfo) error {
if err := t.singlewatch(p, e, dir, fi); err != nil {
if err != errAlreadyWatched {
return nil
}
}
if fi.IsDir() {
err := t.walk(p, func(fi os.FileInfo) (err error) {
if err = t.singlewatch(filepath.Join(p, fi.Name()), e, ndir,
fi); err != nil {
if err != errAlreadyWatched {
return
}
}
return nil
})
if err != nil {
return err
}
}
return nil
}
// walk runs f func on each file/dir from p directory.
func (t *trg) walk(p string, fn func(os.FileInfo) error) error {
fp, err := os.Open(p)
if err != nil {
return err
}
ls, err := fp.Readdir(0)
fp.Close()
if err != nil {
return err
}
for i := range ls {
if err := fn(ls[i]); err != nil {
return err
}
}
return nil
}
func (t *trg) unwatch(p string, fi os.FileInfo) error {
if fi.IsDir() {
err := t.walk(p, func(fi os.FileInfo) error {
err := t.singleunwatch(filepath.Join(p, fi.Name()), ndir)
if err != errNotWatched {
return err
}
return nil
})
if err != nil {
return err
}
}
return t.singleunwatch(p, dir)
}
// Watch implements Watcher interface.
func (t *trg) Watch(p string, e Event) error {
fi, err := os.Stat(p)
if err != nil {
return err
}
t.Lock()
err = t.watch(p, e, fi)
t.Unlock()
return err
}
// Unwatch implements Watcher interface.
func (t *trg) Unwatch(p string) error {
fi, err := os.Stat(p)
if err != nil {
return err
}
t.Lock()
err = t.unwatch(p, fi)
t.Unlock()
return err
}
// Rewatch implements Watcher interface.
//
// TODO(rjeczalik): This is a naive hack. Rewrite might help.
func (t *trg) Rewatch(p string, _, e Event) error {
fi, err := os.Stat(p)
if err != nil {
return err
}
t.Lock()
if err = t.unwatch(p, fi); err == nil {
// TODO(rjeczalik): If watch fails then we leave trigger in inconsistent
// state. Handle? Panic? Native version of rewatch?
err = t.watch(p, e, fi)
}
t.Unlock()
return nil
}
func (*trg) file(w *watched, n interface{}, e Event) (evn []event) {
evn = append(evn, event{w.p, e, w.fi.IsDir(), n})
return
}
func (t *trg) dir(w *watched, n interface{}, e, ge Event) (evn []event) {
// If it's dir and delete we have to send it and continue, because
// other processing relies on opening (in this case not existing) dir.
// Events for contents of this dir are reported by native impl.
// However events for rename must be generated for all monitored files
// inside of moved directory, because native impl does not report it independently
// for each file descriptor being moved in result of move action on
// parent dirLiczba dostępnych dni urlopowych: 0ectory.
if (ge & (not2nat[Rename] | not2nat[Remove])) != 0 {
// Write is reported also for Remove on directory. Because of that
// we have to filter it out explicitly.
evn = append(evn, event{w.p, e & ^Write & ^not2nat[Write], true, n})
if ge&not2nat[Rename] != 0 {
for p := range t.pthLkp {
if strings.HasPrefix(p, w.p+string(os.PathSeparator)) {
if err := t.singleunwatch(p, both); err != nil && err != errNotWatched &&
!os.IsNotExist(err) {
dbgprintf("trg: failed stop watching moved file (%q): %q\n",
p, err)
}
if (w.eDir|w.eNonDir)&(not2nat[Rename]|Rename) != 0 {
evn = append(evn, event{
p, (w.eDir | w.eNonDir) & e &^ Write &^ not2nat[Write],
w.fi.IsDir(), nil,
})
}
}
}
}
t.t.Del(w)
return
}
if (ge & not2nat[Write]) != 0 {
switch err := t.walk(w.p, func(fi os.FileInfo) error {
p := filepath.Join(w.p, fi.Name())
switch err := t.singlewatch(p, w.eDir, ndir, fi); {
case os.IsNotExist(err) && ((w.eDir & Remove) != 0):
evn = append(evn, event{p, Remove, fi.IsDir(), n})
case err == errAlreadyWatched:
case err != nil:
dbgprintf("trg: watching %q failed: %q", p, err)
case (w.eDir & Create) != 0:
evn = append(evn, event{p, Create, fi.IsDir(), n})
default:
}
return nil
}); {
case os.IsNotExist(err):
return
case err != nil:
dbgprintf("trg: dir processing failed: %q", err)
default:
}
}
return
}
type mode uint
const (
dir mode = iota
ndir
both
)
// unwatch stops watching p file/directory.
func (t *trg) singleunwatch(p string, direct mode) error {
w, ok := t.pthLkp[p]
if !ok {
return errNotWatched
}
switch direct {
case dir:
w.eDir = 0
case ndir:
w.eNonDir = 0
case both:
w.eDir, w.eNonDir = 0, 0
}
if err := t.t.Unwatch(w); err != nil {
return err
}
if w.eNonDir|w.eDir != 0 {
mod := dir
if w.eNonDir == 0 {
mod = ndir
}
if err := t.singlewatch(p, w.eNonDir|w.eDir, mod,
w.fi); err != nil && err != errAlreadyWatched {
return err
}
} else {
t.t.Del(w)
}
return nil
}
func (t *trg) monitor() {
var (
n interface{}
err error
)
for {
switch n, err = t.t.Wait(); {
case err == syscall.EINTR:
case t.t.IsStop(n, err):
t.s <- struct{}{}
return
case err != nil:
dbgprintf("trg: failed to read events: %q\n", err)
default:
t.send(t.process(n))
}
}
}
// process event returned by port_get call.
func (t *trg) process(n interface{}) (evn []event) {
t.Lock()
w, ge, err := t.t.Watched(n)
if err != nil {
t.Unlock()
dbgprintf("trg: %v event lookup failed: %q", Event(ge), err)
return
}
e := decode(ge, w.eDir|w.eNonDir)
if ge&int64(not2nat[Remove]|not2nat[Rename]) == 0 {
switch fi, err := os.Stat(w.p); {
case err != nil:
default:
if err = t.t.Watch(fi, w, (encode(w.eDir | w.eNonDir))); err != nil {
dbgprintf("trg: %q is no longer watched: %q", w.p, err)
t.t.Del(w)
}
}
}
if e == Event(0) {
t.Unlock()
return
}
if w.fi.IsDir() {
evn = append(evn, t.dir(w, n, e, Event(ge))...)
} else {
evn = append(evn, t.file(w, n, e)...)
}
if Event(ge)&(not2nat[Remove]|not2nat[Rename]) != 0 {
t.t.Del(w)
}
t.Unlock()
return
}

@ -0,0 +1,103 @@
// 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
// EventDiff describes a change to an event set - EventDiff[0] is an old state,
// while EventDiff[1] is a new state. If event set has not changed (old == new),
// functions typically return the None value.
type eventDiff [2]Event
func (diff eventDiff) Event() Event {
return diff[1] &^ diff[0]
}
// Watchpoint
//
// The nil key holds total event set - logical sum for all registered events.
// It speeds up computing EventDiff for Add method.
//
// The rec key holds an event set for a watchpoints created by RecursiveWatch
// for a Watcher implementation which is not natively recursive.
type watchpoint map[chan<- EventInfo]Event
// None is an empty event diff, think null object.
var none eventDiff
// rec is just a placeholder
var rec = func() (ch chan<- EventInfo) {
ch = make(chan<- EventInfo)
close(ch)
return
}()
func (wp watchpoint) dryAdd(ch chan<- EventInfo, e Event) eventDiff {
if e &^= internal; wp[ch]&e == e {
return none
}
total := wp[ch] &^ internal
return eventDiff{total, total | e}
}
// Add assumes neither c nor e are nil or zero values.
func (wp watchpoint) Add(c chan<- EventInfo, e Event) (diff eventDiff) {
wp[c] |= e
diff[0] = wp[nil]
diff[1] = diff[0] | e
wp[nil] = diff[1] &^ omit
// Strip diff from internal events.
diff[0] &^= internal
diff[1] &^= internal
if diff[0] == diff[1] {
return none
}
return
}
func (wp watchpoint) Del(c chan<- EventInfo, e Event) (diff eventDiff) {
wp[c] &^= e
if wp[c] == 0 {
delete(wp, c)
}
diff[0] = wp[nil]
delete(wp, nil)
if len(wp) != 0 {
// Recalculate total event set.
for _, e := range wp {
diff[1] |= e
}
wp[nil] = diff[1] &^ omit
}
// Strip diff from internal events.
diff[0] &^= internal
diff[1] &^= internal
if diff[0] == diff[1] {
return none
}
return
}
func (wp watchpoint) Dispatch(ei EventInfo, extra Event) {
e := eventmask(ei, extra)
if !matches(wp[nil], e) {
return
}
for ch, eset := range wp {
if ch != nil && matches(eset, e) {
select {
case ch <- ei:
default: // Drop event if receiver is too slow
dbgprintf("dropped %s on %q: receiver too slow", ei.Event(), ei.Path())
}
}
}
}
func (wp watchpoint) Total() Event {
return wp[nil] &^ internal
}
func (wp watchpoint) IsRecursive() bool {
return wp[nil]&recursive != 0
}

@ -0,0 +1,23 @@
// 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.
// +build !windows
package notify
// eventmask uses ei to create a new event which contains internal flags used by
// notify package logic.
func eventmask(ei EventInfo, extra Event) Event {
return ei.Event() | extra
}
// matches reports a match only when:
//
// - for user events, when event is present in the given set
// - for internal events, when additionaly both event and set have omit bit set
//
// Internal events must not be sent to user channels and vice versa.
func matches(set, event Event) bool {
return (set&omit)^(event&omit) == 0 && set&event == event
}

@ -0,0 +1,38 @@
// 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.
// +build windows
package notify
// eventmask uses ei to create a new event which contains internal flags used by
// notify package logic. If one of FileAction* masks is detected, this function
// adds corresponding FileNotifyChange* values. This allows non registered
// FileAction* events to be passed on.
func eventmask(ei EventInfo, extra Event) (e Event) {
if e = ei.Event() | extra; e&fileActionAll != 0 {
if ev, ok := ei.(*event); ok {
switch ev.ftype {
case fTypeFile:
e |= FileNotifyChangeFileName
case fTypeDirectory:
e |= FileNotifyChangeDirName
case fTypeUnknown:
e |= fileNotifyChangeModified
}
return e &^ fileActionAll
}
}
return
}
// matches reports a match only when:
//
// - for user events, when event is present in the given set
// - for internal events, when additionally both event and set have omit bit set
//
// Internal events must not be sent to user channels and vice versa.
func matches(set, event Event) bool {
return (set&omit)^(event&omit) == 0 && (set&event == event || set&fileNotifyChangeModified&event != 0)
}