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Merge pull request #1405 from fuweid/me-async-load-cnicnf

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reload cni network config if has fs change events
This commit is contained in:
Mike Brown
2020-04-15 13:57:32 -05:00
committed by GitHub
parent 3d250b8289 4ce334aa49
commit d531dc492a
17 changed files with 2002 additions and 16 deletions
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121
pkg/server/cni_conf_syncer.go Normal file
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@@ -0,0 +1,121 @@
/*
Copyright The Containerd Authors.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
package server
import (
"os"
"sync"
cni "github.com/containerd/go-cni"
"github.com/fsnotify/fsnotify"
"github.com/pkg/errors"
"github.com/sirupsen/logrus"
)
// cniNetConfSyncer is used to reload cni network conf triggered by fs change
// events.
type cniNetConfSyncer struct {
// only used for lastSyncStatus
sync.RWMutex
lastSyncStatus error
watcher *fsnotify.Watcher
confDir string
netPlugin cni.CNI
loadOpts []cni.CNIOpt
}
// newCNINetConfSyncer creates cni network conf syncer.
func newCNINetConfSyncer(confDir string, netPlugin cni.CNI, loadOpts []cni.CNIOpt) (*cniNetConfSyncer, error) {
watcher, err := fsnotify.NewWatcher()
if err != nil {
return nil, errors.Wrap(err, "failed to create fsnotify watcher")
}
if err := os.MkdirAll(confDir, 0700); err != nil {
return nil, errors.Wrapf(err, "failed to create cni conf dir=%s for watch", confDir)
}
if err := watcher.Add(confDir); err != nil {
return nil, errors.Wrapf(err, "failed to watch cni conf dir %s", confDir)
}
syncer := &cniNetConfSyncer{
watcher: watcher,
confDir: confDir,
netPlugin: netPlugin,
loadOpts: loadOpts,
}
if err := syncer.netPlugin.Load(syncer.loadOpts...); err != nil {
logrus.WithError(err).Error("failed to load cni during init, please check CRI plugin status before setting up network for pods")
syncer.updateLastStatus(err)
}
return syncer, nil
}
// syncLoop monitors any fs change events from cni conf dir and tries to reload
// cni configuration.
func (syncer *cniNetConfSyncer) syncLoop() error {
for {
select {
case event := <-syncer.watcher.Events:
// Only reload config when receiving write/rename/remove
// events
//
// TODO(fuweid): Might only reload target cni config
// files to prevent no-ops.
if event.Op&(fsnotify.Chmod|fsnotify.Create) > 0 {
logrus.Debugf("ignore event from cni conf dir: %s", event)
continue
}
logrus.Debugf("receiving change event from cni conf dir: %s", event)
lerr := syncer.netPlugin.Load(syncer.loadOpts...)
if lerr != nil {
logrus.WithError(lerr).
Errorf("failed to reload cni configuration after receiving fs change event(%s)", event)
}
syncer.updateLastStatus(lerr)
case err := <-syncer.watcher.Errors:
if err != nil {
logrus.WithError(err).Error("failed to continue sync cni conf change")
return err
}
}
}
}
// lastStatus retrieves last sync status.
func (syncer *cniNetConfSyncer) lastStatus() error {
syncer.RLock()
defer syncer.RUnlock()
return syncer.lastSyncStatus
}
// updateLastStatus will be called after every single cni load.
func (syncer *cniNetConfSyncer) updateLastStatus(err error) {
syncer.Lock()
defer syncer.Unlock()
syncer.lastSyncStatus = err
}
// stop stops watcher in the syncLoop.
func (syncer *cniNetConfSyncer) stop() error {
return syncer.watcher.Close()
}

25
pkg/server/service.go
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@@ -91,6 +91,9 @@ type criService struct {
// initialized indicates whether the server is initialized. All GRPC services
// should return error before the server is initialized.
initialized atomic.Bool
// cniNetConfMonitor is used to reload cni network conf if there is
// any valid fs change events from cni network conf dir.
cniNetConfMonitor *cniNetConfSyncer
}
// NewCRIService returns a new instance of CRIService
@@ -128,6 +131,11 @@ func NewCRIService(config criconfig.Config, client *containerd.Client) (CRIServi
c.eventMonitor = newEventMonitor(c)
c.cniNetConfMonitor, err = newCNINetConfSyncer(c.config.NetworkPluginConfDir, c.netPlugin, c.cniLoadOptions())
if err != nil {
return nil, errors.Wrap(err, "failed to create cni conf monitor")
}
return c, nil
}
@@ -169,6 +177,14 @@ func (c *criService) Run() error {
)
snapshotsSyncer.start()
// Start CNI network conf syncer
logrus.Info("Start cni network conf syncer")
cniNetConfMonitorErrCh := make(chan error, 1)
go func() {
defer close(cniNetConfMonitorErrCh)
cniNetConfMonitorErrCh <- c.cniNetConfMonitor.syncLoop()
}()
// Start streaming server.
logrus.Info("Start streaming server")
streamServerErrCh := make(chan error)
@@ -183,11 +199,12 @@ func (c *criService) Run() error {
// Set the server as initialized. GRPC services could start serving traffic.
c.initialized.Set()
var eventMonitorErr, streamServerErr error
var eventMonitorErr, streamServerErr, cniNetConfMonitorErr error
// Stop the whole CRI service if any of the critical service exits.
select {
case eventMonitorErr = <-eventMonitorErrCh:
case streamServerErr = <-streamServerErrCh:
case cniNetConfMonitorErr = <-cniNetConfMonitorErrCh:
}
if err := c.Close(); err != nil {
return errors.Wrap(err, "failed to stop cri service")
@@ -222,6 +239,9 @@ func (c *criService) Run() error {
if streamServerErr != nil {
return errors.Wrap(streamServerErr, "stream server error")
}
if cniNetConfMonitorErr != nil {
return errors.Wrap(cniNetConfMonitorErr, "cni network conf monitor error")
}
return nil
}
@@ -229,6 +249,9 @@ func (c *criService) Run() error {
// TODO(random-liu): Make close synchronous.
func (c *criService) Close() error {
logrus.Info("Stop CRI service")
if err := c.cniNetConfMonitor.stop(); err != nil {
logrus.WithError(err).Error("failed to stop cni network conf monitor")
}
c.eventMonitor.stop()
if err := c.streamServer.Stop(); err != nil {
return errors.Wrap(err, "failed to stop stream server")

5
pkg/server/service_unix.go
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@@ -60,11 +60,6 @@ func (c *criService) initPlatform() error {
return errors.Wrap(err, "failed to initialize cni")
}
// Try to load the config if it exists. Just log the error if load fails
// This is not disruptive for containerd to panic
if err := c.netPlugin.Load(c.cniLoadOptions()...); err != nil {
logrus.WithError(err).Error("Failed to load cni during init, please check CRI plugin status before setting up network for pods")
}
return nil
}

6
pkg/server/service_windows.go
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@@ -21,7 +21,6 @@ package server
import (
cni "github.com/containerd/go-cni"
"github.com/pkg/errors"
"github.com/sirupsen/logrus"
)
// windowsNetworkAttachCount is the minimum number of networks the PodSandbox
@@ -44,11 +43,6 @@ func (c *criService) initPlatform() error {
return errors.Wrap(err, "failed to initialize cni")
}
// Try to load the config if it exists. Just log the error if load fails
// This is not disruptive for containerd to panic
if err := c.netPlugin.Load(c.cniLoadOptions()...); err != nil {
logrus.WithError(err).Error("Failed to load cni during init, please check CRI plugin status before setting up network for pods")
}
return nil
}

10
pkg/server/status.go
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@@ -41,10 +41,6 @@ func (c *criService) Status(ctx context.Context, r *runtime.StatusRequest) (*run
Type: runtime.NetworkReady,
Status: true,
}
// Load the latest cni configuration to be in sync with the latest network configuration
if err := c.netPlugin.Load(c.cniLoadOptions()...); err != nil {
log.G(ctx).WithError(err).Errorf("Failed to load cni configuration")
}
// Check the status of the cni initialization
if err := c.netPlugin.Status(); err != nil {
networkCondition.Status = false
@@ -76,6 +72,12 @@ func (c *criService) Status(ctx context.Context, r *runtime.StatusRequest) (*run
log.G(ctx).WithError(err).Errorf("Failed to marshal CNI config %v", err)
}
resp.Info["cniconfig"] = string(cniConfig)
lastCNILoadStatus := "OK"
if lerr := c.cniNetConfMonitor.lastStatus(); lerr != nil {
lastCNILoadStatus = lerr.Error()
}
resp.Info["lastCNILoadStatus"] = lastCNILoadStatus
}
return resp, nil
}

1
vendor.conf
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@@ -89,6 +89,7 @@ sigs.k8s.io/yaml 9fc95527decd95bb9d28cc2eab08
github.com/containerd/go-cni 0d360c50b10b350b6bb23863fd4dfb1c232b01c9
github.com/containernetworking/cni 4cfb7b568922a3c79a23e438dc52fe537fc9687e # v0.7.1
github.com/containernetworking/plugins 9f96827c7cabb03f21d86326000c00f61e181f6a # v0.7.6
github.com/fsnotify/fsnotify 4bf2d1fec78374803a39307bfb8d340688f4f28e # v1.4.8
# image decrypt depedencies
github.com/containerd/imgcrypt 9e761ccd6069fb707ec9493435f31475b5524b38 # v1.0.1

28
vendor/github.com/fsnotify/fsnotify/LICENSE generated vendored Normal file
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@@ -0,0 +1,28 @@
Copyright (c) 2012 The Go Authors. All rights reserved.
Copyright (c) 2012-2019 fsnotify Authors. All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are
met:
* Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above
copyright notice, this list of conditions and the following disclaimer
in the documentation and/or other materials provided with the
distribution.
* Neither the name of Google Inc. nor the names of its
contributors may be used to endorse or promote products derived from
this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

83
vendor/github.com/fsnotify/fsnotify/README.md generated vendored Normal file
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@@ -0,0 +1,83 @@
# File system notifications for Go
[![GoDoc](https://godoc.org/github.com/fsnotify/fsnotify?status.svg)](https://godoc.org/github.com/fsnotify/fsnotify) [![Go Report Card](https://goreportcard.com/badge/github.com/fsnotify/fsnotify)](https://goreportcard.com/report/github.com/fsnotify/fsnotify)
fsnotify utilizes [golang.org/x/sys](https://godoc.org/golang.org/x/sys) rather than `syscall` from the standard library. Ensure you have the latest version installed by running:
```console
go get -u golang.org/x/sys/...
```
Cross platform: Windows, Linux, BSD and macOS.
| Adapter | OS | Status |
| --------------------- | -------------------------------- | ------------------------------------------------------------------------------------------------------------------------------- |
| inotify | Linux 2.6.27 or later, Android\* | Supported [![Build Status](https://travis-ci.org/fsnotify/fsnotify.svg?branch=master)](https://travis-ci.org/fsnotify/fsnotify) |
| kqueue | BSD, macOS, iOS\* | Supported [![Build Status](https://travis-ci.org/fsnotify/fsnotify.svg?branch=master)](https://travis-ci.org/fsnotify/fsnotify) |
| ReadDirectoryChangesW | Windows | Supported [![Build Status](https://travis-ci.org/fsnotify/fsnotify.svg?branch=master)](https://travis-ci.org/fsnotify/fsnotify) |
| FSEvents | macOS | [Planned](https://github.com/fsnotify/fsnotify/issues/11) |
| FEN | Solaris 11 | [In Progress](https://github.com/fsnotify/fsnotify/issues/12) |
| fanotify | Linux 2.6.37+ | [Planned](https://github.com/fsnotify/fsnotify/issues/114) |
| USN Journals | Windows | [Maybe](https://github.com/fsnotify/fsnotify/issues/53) |
| Polling | *All* | [Maybe](https://github.com/fsnotify/fsnotify/issues/9) |
\* Android and iOS are untested.
Please see [the documentation](https://godoc.org/github.com/fsnotify/fsnotify) and consult the [FAQ](#faq) for usage information.
## API stability
fsnotify is a fork of [howeyc/fsnotify](https://godoc.org/github.com/howeyc/fsnotify) with a new API as of v1.0. The API is based on [this design document](http://goo.gl/MrYxyA).
All [releases](https://github.com/fsnotify/fsnotify/releases) are tagged based on [Semantic Versioning](http://semver.org/). Further API changes are [planned](https://github.com/fsnotify/fsnotify/milestones), and will be tagged with a new major revision number.
Go 1.6 supports dependencies located in the `vendor/` folder. Unless you are creating a library, it is recommended that you copy fsnotify into `vendor/github.com/fsnotify/fsnotify` within your project, and likewise for `golang.org/x/sys`.
## Contributing
Please refer to [CONTRIBUTING][] before opening an issue or pull request.
## Example
See [example_test.go](https://github.com/fsnotify/fsnotify/blob/master/example_test.go).
## FAQ
**When a file is moved to another directory is it still being watched?**
No (it shouldn't be, unless you are watching where it was moved to).
**When I watch a directory, are all subdirectories watched as well?**
No, you must add watches for any directory you want to watch (a recursive watcher is on the roadmap [#18][]).
**Do I have to watch the Error and Event channels in a separate goroutine?**
As of now, yes. Looking into making this single-thread friendly (see [howeyc #7][#7])
**Why am I receiving multiple events for the same file on OS X?**
Spotlight indexing on OS X can result in multiple events (see [howeyc #62][#62]). A temporary workaround is to add your folder(s) to the *Spotlight Privacy settings* until we have a native FSEvents implementation (see [#11][]).
**How many files can be watched at once?**
There are OS-specific limits as to how many watches can be created:
* Linux: /proc/sys/fs/inotify/max_user_watches contains the limit, reaching this limit results in a "no space left on device" error.
* BSD / OSX: sysctl variables "kern.maxfiles" and "kern.maxfilesperproc", reaching these limits results in a "too many open files" error.
**Why don't notifications work with NFS filesystems or filesystem in userspace (FUSE)?**
fsnotify requires support from underlying OS to work. The current NFS protocol does not provide network level support for file notifications.
[#62]: https://github.com/howeyc/fsnotify/issues/62
[#18]: https://github.com/fsnotify/fsnotify/issues/18
[#11]: https://github.com/fsnotify/fsnotify/issues/11
[#7]: https://github.com/howeyc/fsnotify/issues/7
[contributing]: https://github.com/fsnotify/fsnotify/blob/master/CONTRIBUTING.md
## Related Projects
* [notify](https://github.com/rjeczalik/notify)
* [fsevents](https://github.com/fsnotify/fsevents)

37
vendor/github.com/fsnotify/fsnotify/fen.go generated vendored Normal file
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@@ -0,0 +1,37 @@
// Copyright 2010 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build solaris
package fsnotify
import (
"errors"
)
// Watcher watches a set of files, delivering events to a channel.
type Watcher struct {
Events chan Event
Errors chan error
}
// NewWatcher establishes a new watcher with the underlying OS and begins waiting for events.
func NewWatcher() (*Watcher, error) {
return nil, errors.New("FEN based watcher not yet supported for fsnotify\n")
}
// Close removes all watches and closes the events channel.
func (w *Watcher) Close() error {
return nil
}
// Add starts watching the named file or directory (non-recursively).
func (w *Watcher) Add(name string) error {
return nil
}
// Remove stops watching the the named file or directory (non-recursively).
func (w *Watcher) Remove(name string) error {
return nil
}

68
vendor/github.com/fsnotify/fsnotify/fsnotify.go generated vendored Normal file
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@@ -0,0 +1,68 @@
// Copyright 2012 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build !plan9
// Package fsnotify provides a platform-independent interface for file system notifications.
package fsnotify
import (
"bytes"
"errors"
"fmt"
)
// Event represents a single file system notification.
type Event struct {
Name string // Relative path to the file or directory.
Op Op // File operation that triggered the event.
}
// Op describes a set of file operations.
type Op uint32
// These are the generalized file operations that can trigger a notification.
const (
Create Op = 1 << iota
Write
Remove
Rename
Chmod
)
func (op Op) String() string {
// Use a buffer for efficient string concatenation
var buffer bytes.Buffer
if op&Create == Create {
buffer.WriteString("|CREATE")
}
if op&Remove == Remove {
buffer.WriteString("|REMOVE")
}
if op&Write == Write {
buffer.WriteString("|WRITE")
}
if op&Rename == Rename {
buffer.WriteString("|RENAME")
}
if op&Chmod == Chmod {
buffer.WriteString("|CHMOD")
}
if buffer.Len() == 0 {
return ""
}
return buffer.String()[1:] // Strip leading pipe
}
// String returns a string representation of the event in the form
// "file: REMOVE|WRITE|..."
func (e Event) String() string {
return fmt.Sprintf("%q: %s", e.Name, e.Op.String())
}
// Common errors that can be reported by a watcher
var (
ErrEventOverflow = errors.New("fsnotify queue overflow")
)

5
vendor/github.com/fsnotify/fsnotify/go.mod generated vendored Normal file
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@@ -0,0 +1,5 @@
module github.com/fsnotify/fsnotify
go 1.13
require golang.org/x/sys v0.0.0-20191005200804-aed5e4c7ecf9

337
vendor/github.com/fsnotify/fsnotify/inotify.go generated vendored Normal file
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@@ -0,0 +1,337 @@
// Copyright 2010 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build linux
package fsnotify
import (
"errors"
"fmt"
"io"
"os"
"path/filepath"
"strings"
"sync"
"unsafe"
"golang.org/x/sys/unix"
)
// Watcher watches a set of files, delivering events to a channel.
type Watcher struct {
Events chan Event
Errors chan error
mu sync.Mutex // Map access
fd int
poller *fdPoller
watches map[string]*watch // Map of inotify watches (key: path)
paths map[int]string // Map of watched paths (key: watch descriptor)
done chan struct{} // Channel for sending a "quit message" to the reader goroutine
doneResp chan struct{} // Channel to respond to Close
}
// NewWatcher establishes a new watcher with the underlying OS and begins waiting for events.
func NewWatcher() (*Watcher, error) {
// Create inotify fd
fd, errno := unix.InotifyInit1(unix.IN_CLOEXEC)
if fd == -1 {
return nil, errno
}
// Create epoll
poller, err := newFdPoller(fd)
if err != nil {
unix.Close(fd)
return nil, err
}
w := &Watcher{
fd: fd,
poller: poller,
watches: make(map[string]*watch),
paths: make(map[int]string),
Events: make(chan Event),
Errors: make(chan error),
done: make(chan struct{}),
doneResp: make(chan struct{}),
}
go w.readEvents()
return w, nil
}
func (w *Watcher) isClosed() bool {
select {
case <-w.done:
return true
default:
return false
}
}
// Close removes all watches and closes the events channel.
func (w *Watcher) Close() error {
if w.isClosed() {
return nil
}
// Send 'close' signal to goroutine, and set the Watcher to closed.
close(w.done)
// Wake up goroutine
w.poller.wake()
// Wait for goroutine to close
<-w.doneResp
return nil
}
// Add starts watching the named file or directory (non-recursively).
func (w *Watcher) Add(name string) error {
name = filepath.Clean(name)
if w.isClosed() {
return errors.New("inotify instance already closed")
}
const agnosticEvents = unix.IN_MOVED_TO | unix.IN_MOVED_FROM |
unix.IN_CREATE | unix.IN_ATTRIB | unix.IN_MODIFY |
unix.IN_MOVE_SELF | unix.IN_DELETE | unix.IN_DELETE_SELF
var flags uint32 = agnosticEvents
w.mu.Lock()
defer w.mu.Unlock()
watchEntry := w.watches[name]
if watchEntry != nil {
flags |= watchEntry.flags | unix.IN_MASK_ADD
}
wd, errno := unix.InotifyAddWatch(w.fd, name, flags)
if wd == -1 {
return errno
}
if watchEntry == nil {
w.watches[name] = &watch{wd: uint32(wd), flags: flags}
w.paths[wd] = name
} else {
watchEntry.wd = uint32(wd)
watchEntry.flags = flags
}
return nil
}
// Remove stops watching the named file or directory (non-recursively).
func (w *Watcher) Remove(name string) error {
name = filepath.Clean(name)
// Fetch the watch.
w.mu.Lock()
defer w.mu.Unlock()
watch, ok := w.watches[name]
// Remove it from inotify.
if !ok {
return fmt.Errorf("can't remove non-existent inotify watch for: %s", name)
}
// We successfully removed the watch if InotifyRmWatch doesn't return an
// error, we need to clean up our internal state to ensure it matches
// inotify's kernel state.
delete(w.paths, int(watch.wd))
delete(w.watches, name)
// inotify_rm_watch will return EINVAL if the file has been deleted;
// the inotify will already have been removed.
// watches and pathes are deleted in ignoreLinux() implicitly and asynchronously
// by calling inotify_rm_watch() below. e.g. readEvents() goroutine receives IN_IGNORE
// so that EINVAL means that the wd is being rm_watch()ed or its file removed
// by another thread and we have not received IN_IGNORE event.
success, errno := unix.InotifyRmWatch(w.fd, watch.wd)
if success == -1 {
// TODO: Perhaps it's not helpful to return an error here in every case.
// the only two possible errors are:
// EBADF, which happens when w.fd is not a valid file descriptor of any kind.
// EINVAL, which is when fd is not an inotify descriptor or wd is not a valid watch descriptor.
// Watch descriptors are invalidated when they are removed explicitly or implicitly;
// explicitly by inotify_rm_watch, implicitly when the file they are watching is deleted.
return errno
}
return nil
}
type watch struct {
wd uint32 // Watch descriptor (as returned by the inotify_add_watch() syscall)
flags uint32 // inotify flags of this watch (see inotify(7) for the list of valid flags)
}
// readEvents reads from the inotify file descriptor, converts the
// received events into Event objects and sends them via the Events channel
func (w *Watcher) readEvents() {
var (
buf [unix.SizeofInotifyEvent * 4096]byte // Buffer for a maximum of 4096 raw events
n int // Number of bytes read with read()
errno error // Syscall errno
ok bool // For poller.wait
)
defer close(w.doneResp)
defer close(w.Errors)
defer close(w.Events)
defer unix.Close(w.fd)
defer w.poller.close()
for {
// See if we have been closed.
if w.isClosed() {
return
}
ok, errno = w.poller.wait()
if errno != nil {
select {
case w.Errors <- errno:
case <-w.done:
return
}
continue
}
if !ok {
continue
}
n, errno = unix.Read(w.fd, buf[:])
// If a signal interrupted execution, see if we've been asked to close, and try again.
// http://man7.org/linux/man-pages/man7/signal.7.html :
// "Before Linux 3.8, reads from an inotify(7) file descriptor were not restartable"
if errno == unix.EINTR {
continue
}
// unix.Read might have been woken up by Close. If so, we're done.
if w.isClosed() {
return
}
if n < unix.SizeofInotifyEvent {
var err error
if n == 0 {
// If EOF is received. This should really never happen.
err = io.EOF
} else if n < 0 {
// If an error occurred while reading.
err = errno
} else {
// Read was too short.
err = errors.New("notify: short read in readEvents()")
}
select {
case w.Errors <- err:
case <-w.done:
return
}
continue
}
var offset uint32
// We don't know how many events we just read into the buffer
// While the offset points to at least one whole event...
for offset <= uint32(n-unix.SizeofInotifyEvent) {
// Point "raw" to the event in the buffer
raw := (*unix.InotifyEvent)(unsafe.Pointer(&buf[offset]))
mask := uint32(raw.Mask)
nameLen := uint32(raw.Len)
if mask&unix.IN_Q_OVERFLOW != 0 {
select {
case w.Errors <- ErrEventOverflow:
case <-w.done:
return
}
}
// If the event happened to the watched directory or the watched file, the kernel
// doesn't append the filename to the event, but we would like to always fill the
// the "Name" field with a valid filename. We retrieve the path of the watch from
// the "paths" map.
w.mu.Lock()
name, ok := w.paths[int(raw.Wd)]
// IN_DELETE_SELF occurs when the file/directory being watched is removed.
// This is a sign to clean up the maps, otherwise we are no longer in sync
// with the inotify kernel state which has already deleted the watch
// automatically.
if ok && mask&unix.IN_DELETE_SELF == unix.IN_DELETE_SELF {
delete(w.paths, int(raw.Wd))
delete(w.watches, name)
}
w.mu.Unlock()
if nameLen > 0 {
// Point "bytes" at the first byte of the filename
bytes := (*[unix.PathMax]byte)(unsafe.Pointer(&buf[offset+unix.SizeofInotifyEvent]))
// The filename is padded with NULL bytes. TrimRight() gets rid of those.
name += "/" + strings.TrimRight(string(bytes[0:nameLen]), "\000")
}
event := newEvent(name, mask)
// Send the events that are not ignored on the events channel
if !event.ignoreLinux(mask) {
select {
case w.Events <- event:
case <-w.done:
return
}
}
// Move to the next event in the buffer
offset += unix.SizeofInotifyEvent + nameLen
}
}
}
// Certain types of events can be "ignored" and not sent over the Events
// channel. Such as events marked ignore by the kernel, or MODIFY events
// against files that do not exist.
func (e *Event) ignoreLinux(mask uint32) bool {
// Ignore anything the inotify API says to ignore
if mask&unix.IN_IGNORED == unix.IN_IGNORED {
return true
}
// If the event is not a DELETE or RENAME, the file must exist.
// Otherwise the event is ignored.
// *Note*: this was put in place because it was seen that a MODIFY
// event was sent after the DELETE. This ignores that MODIFY and
// assumes a DELETE will come or has come if the file doesn't exist.
if !(e.Op&Remove == Remove || e.Op&Rename == Rename) {
_, statErr := os.Lstat(e.Name)
return os.IsNotExist(statErr)
}
return false
}
// newEvent returns an platform-independent Event based on an inotify mask.
func newEvent(name string, mask uint32) Event {
e := Event{Name: name}
if mask&unix.IN_CREATE == unix.IN_CREATE || mask&unix.IN_MOVED_TO == unix.IN_MOVED_TO {
e.Op |= Create
}
if mask&unix.IN_DELETE_SELF == unix.IN_DELETE_SELF || mask&unix.IN_DELETE == unix.IN_DELETE {
e.Op |= Remove
}
if mask&unix.IN_MODIFY == unix.IN_MODIFY {
e.Op |= Write
}
if mask&unix.IN_MOVE_SELF == unix.IN_MOVE_SELF || mask&unix.IN_MOVED_FROM == unix.IN_MOVED_FROM {
e.Op |= Rename
}
if mask&unix.IN_ATTRIB == unix.IN_ATTRIB {
e.Op |= Chmod
}
return e
}

187
vendor/github.com/fsnotify/fsnotify/inotify_poller.go generated vendored Normal file
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@@ -0,0 +1,187 @@
// Copyright 2015 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build linux
package fsnotify
import (
"errors"
"golang.org/x/sys/unix"
)
type fdPoller struct {
fd int // File descriptor (as returned by the inotify_init() syscall)
epfd int // Epoll file descriptor
pipe [2]int // Pipe for waking up
}
func emptyPoller(fd int) *fdPoller {
poller := new(fdPoller)
poller.fd = fd
poller.epfd = -1
poller.pipe[0] = -1
poller.pipe[1] = -1
return poller
}
// Create a new inotify poller.
// This creates an inotify handler, and an epoll handler.
func newFdPoller(fd int) (*fdPoller, error) {
var errno error
poller := emptyPoller(fd)
defer func() {
if errno != nil {
poller.close()
}
}()
poller.fd = fd
// Create epoll fd
poller.epfd, errno = unix.EpollCreate1(unix.EPOLL_CLOEXEC)
if poller.epfd == -1 {
return nil, errno
}
// Create pipe; pipe[0] is the read end, pipe[1] the write end.
errno = unix.Pipe2(poller.pipe[:], unix.O_NONBLOCK|unix.O_CLOEXEC)
if errno != nil {
return nil, errno
}
// Register inotify fd with epoll
event := unix.EpollEvent{
Fd: int32(poller.fd),
Events: unix.EPOLLIN,
}
errno = unix.EpollCtl(poller.epfd, unix.EPOLL_CTL_ADD, poller.fd, &event)
if errno != nil {
return nil, errno
}
// Register pipe fd with epoll
event = unix.EpollEvent{
Fd: int32(poller.pipe[0]),
Events: unix.EPOLLIN,
}
errno = unix.EpollCtl(poller.epfd, unix.EPOLL_CTL_ADD, poller.pipe[0], &event)
if errno != nil {
return nil, errno
}
return poller, nil
}
// Wait using epoll.
// Returns true if something is ready to be read,
// false if there is not.
func (poller *fdPoller) wait() (bool, error) {
// 3 possible events per fd, and 2 fds, makes a maximum of 6 events.
// I don't know whether epoll_wait returns the number of events returned,
// or the total number of events ready.
// I decided to catch both by making the buffer one larger than the maximum.
events := make([]unix.EpollEvent, 7)
for {
n, errno := unix.EpollWait(poller.epfd, events, -1)
if n == -1 {
if errno == unix.EINTR {
continue
}
return false, errno
}
if n == 0 {
// If there are no events, try again.
continue
}
if n > 6 {
// This should never happen. More events were returned than should be possible.
return false, errors.New("epoll_wait returned more events than I know what to do with")
}
ready := events[:n]
epollhup := false
epollerr := false
epollin := false
for _, event := range ready {
if event.Fd == int32(poller.fd) {
if event.Events&unix.EPOLLHUP != 0 {
// This should not happen, but if it does, treat it as a wakeup.
epollhup = true
}
if event.Events&unix.EPOLLERR != 0 {
// If an error is waiting on the file descriptor, we should pretend
// something is ready to read, and let unix.Read pick up the error.
epollerr = true
}
if event.Events&unix.EPOLLIN != 0 {
// There is data to read.
epollin = true
}
}
if event.Fd == int32(poller.pipe[0]) {
if event.Events&unix.EPOLLHUP != 0 {
// Write pipe descriptor was closed, by us. This means we're closing down the
// watcher, and we should wake up.
}
if event.Events&unix.EPOLLERR != 0 {
// If an error is waiting on the pipe file descriptor.
// This is an absolute mystery, and should never ever happen.
return false, errors.New("Error on the pipe descriptor.")
}
if event.Events&unix.EPOLLIN != 0 {
// This is a regular wakeup, so we have to clear the buffer.
err := poller.clearWake()
if err != nil {
return false, err
}
}
}
}
if epollhup || epollerr || epollin {
return true, nil
}
return false, nil
}
}
// Close the write end of the poller.
func (poller *fdPoller) wake() error {
buf := make([]byte, 1)
n, errno := unix.Write(poller.pipe[1], buf)
if n == -1 {
if errno == unix.EAGAIN {
// Buffer is full, poller will wake.
return nil
}
return errno
}
return nil
}
func (poller *fdPoller) clearWake() error {
// You have to be woken up a LOT in order to get to 100!
buf := make([]byte, 100)
n, errno := unix.Read(poller.pipe[0], buf)
if n == -1 {
if errno == unix.EAGAIN {
// Buffer is empty, someone else cleared our wake.
return nil
}
return errno
}
return nil
}
// Close all poller file descriptors, but not the one passed to it.
func (poller *fdPoller) close() {
if poller.pipe[1] != -1 {
unix.Close(poller.pipe[1])
}
if poller.pipe[0] != -1 {
unix.Close(poller.pipe[0])
}
if poller.epfd != -1 {
unix.Close(poller.epfd)
}
}

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

11
vendor/github.com/fsnotify/fsnotify/open_mode_bsd.go generated vendored Normal file
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@@ -0,0 +1,11 @@
// Copyright 2013 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build freebsd openbsd netbsd dragonfly
package fsnotify
import "golang.org/x/sys/unix"
const openMode = unix.O_NONBLOCK | unix.O_RDONLY | unix.O_CLOEXEC

12
vendor/github.com/fsnotify/fsnotify/open_mode_darwin.go generated vendored Normal file
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@@ -0,0 +1,12 @@
// Copyright 2013 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build darwin
package fsnotify
import "golang.org/x/sys/unix"
// note: this constant is not defined on BSD
const openMode = unix.O_EVTONLY | unix.O_CLOEXEC

561
vendor/github.com/fsnotify/fsnotify/windows.go generated vendored Normal file
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@@ -0,0 +1,561 @@
// Copyright 2011 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build windows
package fsnotify
import (
"errors"
"fmt"
"os"
"path/filepath"
"runtime"
"sync"
"syscall"
"unsafe"
)
// Watcher watches a set of files, delivering events to a channel.
type Watcher struct {
Events chan Event
Errors chan error
isClosed bool // Set to true when Close() is first called
mu sync.Mutex // Map access
port syscall.Handle // Handle to completion port
watches watchMap // Map of watches (key: i-number)
input chan *input // Inputs to the reader are sent on this channel
quit chan chan<- error
}
// NewWatcher establishes a new watcher with the underlying OS and begins waiting for events.
func NewWatcher() (*Watcher, error) {
port, e := syscall.CreateIoCompletionPort(syscall.InvalidHandle, 0, 0, 0)
if e != nil {
return nil, os.NewSyscallError("CreateIoCompletionPort", e)
}
w := &Watcher{
port: port,
watches: make(watchMap),
input: make(chan *input, 1),
Events: make(chan Event, 50),
Errors: make(chan error),
quit: make(chan chan<- error, 1),
}
go w.readEvents()
return w, nil
}
// Close removes all watches and closes the events channel.
func (w *Watcher) Close() error {
if w.isClosed {
return nil
}
w.isClosed = true
// Send "quit" message to the reader goroutine
ch := make(chan error)
w.quit <- ch
if err := w.wakeupReader(); err != nil {
return err
}
return <-ch
}
// Add starts watching the named file or directory (non-recursively).
func (w *Watcher) Add(name string) error {
if w.isClosed {
return errors.New("watcher already closed")
}
in := &input{
op: opAddWatch,
path: filepath.Clean(name),
flags: sysFSALLEVENTS,
reply: make(chan error),
}
w.input <- in
if err := w.wakeupReader(); err != nil {
return err
}
return <-in.reply
}
// Remove stops watching the the named file or directory (non-recursively).
func (w *Watcher) Remove(name string) error {
in := &input{
op: opRemoveWatch,
path: filepath.Clean(name),
reply: make(chan error),
}
w.input <- in
if err := w.wakeupReader(); err != nil {
return err
}
return <-in.reply
}
const (
// Options for AddWatch
sysFSONESHOT = 0x80000000
sysFSONLYDIR = 0x1000000
// Events
sysFSACCESS = 0x1
sysFSALLEVENTS = 0xfff
sysFSATTRIB = 0x4
sysFSCLOSE = 0x18
sysFSCREATE = 0x100
sysFSDELETE = 0x200
sysFSDELETESELF = 0x400
sysFSMODIFY = 0x2
sysFSMOVE = 0xc0
sysFSMOVEDFROM = 0x40
sysFSMOVEDTO = 0x80
sysFSMOVESELF = 0x800
// Special events
sysFSIGNORED = 0x8000
sysFSQOVERFLOW = 0x4000
)
func newEvent(name string, mask uint32) Event {
e := Event{Name: name}
if mask&sysFSCREATE == sysFSCREATE || mask&sysFSMOVEDTO == sysFSMOVEDTO {
e.Op |= Create
}
if mask&sysFSDELETE == sysFSDELETE || mask&sysFSDELETESELF == sysFSDELETESELF {
e.Op |= Remove
}
if mask&sysFSMODIFY == sysFSMODIFY {
e.Op |= Write
}
if mask&sysFSMOVE == sysFSMOVE || mask&sysFSMOVESELF == sysFSMOVESELF || mask&sysFSMOVEDFROM == sysFSMOVEDFROM {
e.Op |= Rename
}
if mask&sysFSATTRIB == sysFSATTRIB {
e.Op |= Chmod
}
return e
}
const (
opAddWatch = iota
opRemoveWatch
)
const (
provisional uint64 = 1 << (32 + iota)
)
type input struct {
op int
path string
flags uint32
reply chan error
}
type inode struct {
handle syscall.Handle
volume uint32
index uint64
}
type watch struct {
ov syscall.Overlapped
ino *inode // i-number
path string // Directory path
mask uint64 // Directory itself is being watched with these notify flags
names map[string]uint64 // Map of names being watched and their notify flags
rename string // Remembers the old name while renaming a file
buf [4096]byte
}
type indexMap map[uint64]*watch
type watchMap map[uint32]indexMap
func (w *Watcher) wakeupReader() error {
e := syscall.PostQueuedCompletionStatus(w.port, 0, 0, nil)
if e != nil {
return os.NewSyscallError("PostQueuedCompletionStatus", e)
}
return nil
}
func getDir(pathname string) (dir string, err error) {
attr, e := syscall.GetFileAttributes(syscall.StringToUTF16Ptr(pathname))
if e != nil {
return "", os.NewSyscallError("GetFileAttributes", e)
}
if attr&syscall.FILE_ATTRIBUTE_DIRECTORY != 0 {
dir = pathname
} else {
dir, _ = filepath.Split(pathname)
dir = filepath.Clean(dir)
}
return
}
func getIno(path string) (ino *inode, err error) {
h, e := syscall.CreateFile(syscall.StringToUTF16Ptr(path),
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)
if e != nil {
return nil, os.NewSyscallError("CreateFile", e)
}
var fi syscall.ByHandleFileInformation
if e = syscall.GetFileInformationByHandle(h, &fi); e != nil {
syscall.CloseHandle(h)
return nil, os.NewSyscallError("GetFileInformationByHandle", e)
}
ino = &inode{
handle: h,
volume: fi.VolumeSerialNumber,
index: uint64(fi.FileIndexHigh)<<32 | uint64(fi.FileIndexLow),
}
return ino, nil
}
// Must run within the I/O thread.
func (m watchMap) get(ino *inode) *watch {
if i := m[ino.volume]; i != nil {
return i[ino.index]
}
return nil
}
// Must run within the I/O thread.
func (m watchMap) set(ino *inode, watch *watch) {
i := m[ino.volume]
if i == nil {
i = make(indexMap)
m[ino.volume] = i
}
i[ino.index] = watch
}
// Must run within the I/O thread.
func (w *Watcher) addWatch(pathname string, flags uint64) error {
dir, err := getDir(pathname)
if err != nil {
return err
}
if flags&sysFSONLYDIR != 0 && pathname != dir {
return nil
}
ino, err := getIno(dir)
if err != nil {
return err
}
w.mu.Lock()
watchEntry := w.watches.get(ino)
w.mu.Unlock()
if watchEntry == nil {
if _, e := syscall.CreateIoCompletionPort(ino.handle, w.port, 0, 0); e != nil {
syscall.CloseHandle(ino.handle)
return os.NewSyscallError("CreateIoCompletionPort", e)
}
watchEntry = &watch{
ino: ino,
path: dir,
names: make(map[string]uint64),
}
w.mu.Lock()
w.watches.set(ino, watchEntry)
w.mu.Unlock()
flags |= provisional
} else {
syscall.CloseHandle(ino.handle)
}
if pathname == dir {
watchEntry.mask |= flags
} else {
watchEntry.names[filepath.Base(pathname)] |= flags
}
if err = w.startRead(watchEntry); err != nil {
return err
}
if pathname == dir {
watchEntry.mask &= ^provisional
} else {
watchEntry.names[filepath.Base(pathname)] &= ^provisional
}
return nil
}
// Must run within the I/O thread.
func (w *Watcher) remWatch(pathname string) error {
dir, err := getDir(pathname)
if err != nil {
return err
}
ino, err := getIno(dir)
if err != nil {
return err
}
w.mu.Lock()
watch := w.watches.get(ino)
w.mu.Unlock()
if watch == nil {
return fmt.Errorf("can't remove non-existent watch for: %s", pathname)
}
if pathname == dir {
w.sendEvent(watch.path, watch.mask&sysFSIGNORED)
watch.mask = 0
} else {
name := filepath.Base(pathname)
w.sendEvent(filepath.Join(watch.path, name), watch.names[name]&sysFSIGNORED)
delete(watch.names, name)
}
return w.startRead(watch)
}
// Must run within the I/O thread.
func (w *Watcher) deleteWatch(watch *watch) {
for name, mask := range watch.names {
if mask&provisional == 0 {
w.sendEvent(filepath.Join(watch.path, name), mask&sysFSIGNORED)
}
delete(watch.names, name)
}
if watch.mask != 0 {
if watch.mask&provisional == 0 {
w.sendEvent(watch.path, watch.mask&sysFSIGNORED)
}
watch.mask = 0
}
}
// Must run within the I/O thread.
func (w *Watcher) startRead(watch *watch) error {
if e := syscall.CancelIo(watch.ino.handle); e != nil {
w.Errors <- os.NewSyscallError("CancelIo", e)
w.deleteWatch(watch)
}
mask := toWindowsFlags(watch.mask)
for _, m := range watch.names {
mask |= toWindowsFlags(m)
}
if mask == 0 {
if e := syscall.CloseHandle(watch.ino.handle); e != nil {
w.Errors <- os.NewSyscallError("CloseHandle", e)
}
w.mu.Lock()
delete(w.watches[watch.ino.volume], watch.ino.index)
w.mu.Unlock()
return nil
}
e := syscall.ReadDirectoryChanges(watch.ino.handle, &watch.buf[0],
uint32(unsafe.Sizeof(watch.buf)), false, mask, nil, &watch.ov, 0)
if e != nil {
err := os.NewSyscallError("ReadDirectoryChanges", e)
if e == syscall.ERROR_ACCESS_DENIED && watch.mask&provisional == 0 {
// Watched directory was probably removed
if w.sendEvent(watch.path, watch.mask&sysFSDELETESELF) {
if watch.mask&sysFSONESHOT != 0 {
watch.mask = 0
}
}
err = nil
}
w.deleteWatch(watch)
w.startRead(watch)
return err
}
return nil
}
// readEvents reads from the I/O completion port, converts the
// received events into Event objects and sends them via the Events channel.
// Entry point to the I/O thread.
func (w *Watcher) readEvents() {
var (
n, key uint32
ov *syscall.Overlapped
)
runtime.LockOSThread()
for {
e := syscall.GetQueuedCompletionStatus(w.port, &n, &key, &ov, syscall.INFINITE)
watch := (*watch)(unsafe.Pointer(ov))
if watch == nil {
select {
case ch := <-w.quit:
w.mu.Lock()
var indexes []indexMap
for _, index := range w.watches {
indexes = append(indexes, index)
}
w.mu.Unlock()
for _, index := range indexes {
for _, watch := range index {
w.deleteWatch(watch)
w.startRead(watch)
}
}
var err error
if e := syscall.CloseHandle(w.port); e != nil {
err = os.NewSyscallError("CloseHandle", e)
}
close(w.Events)
close(w.Errors)
ch <- err
return
case in := <-w.input:
switch in.op {
case opAddWatch:
in.reply <- w.addWatch(in.path, uint64(in.flags))
case opRemoveWatch:
in.reply <- w.remWatch(in.path)
}
default:
}
continue
}
switch e {
case syscall.ERROR_MORE_DATA:
if watch == nil {
w.Errors <- errors.New("ERROR_MORE_DATA has unexpectedly null lpOverlapped buffer")
} else {
// The i/o succeeded but the buffer is full.
// In theory we should be building up a full packet.
// In practice we can get away with just carrying on.
n = uint32(unsafe.Sizeof(watch.buf))
}
case syscall.ERROR_ACCESS_DENIED:
// Watched directory was probably removed
w.sendEvent(watch.path, watch.mask&sysFSDELETESELF)
w.deleteWatch(watch)
w.startRead(watch)
continue
case syscall.ERROR_OPERATION_ABORTED:
// CancelIo was called on this handle
continue
default:
w.Errors <- os.NewSyscallError("GetQueuedCompletionPort", e)
continue
case nil:
}
var offset uint32
for {
if n == 0 {
w.Events <- newEvent("", sysFSQOVERFLOW)
w.Errors <- errors.New("short read in readEvents()")
break
}
// Point "raw" to the event in the buffer
raw := (*syscall.FileNotifyInformation)(unsafe.Pointer(&watch.buf[offset]))
buf := (*[syscall.MAX_PATH]uint16)(unsafe.Pointer(&raw.FileName))
name := syscall.UTF16ToString(buf[:raw.FileNameLength/2])
fullname := filepath.Join(watch.path, name)
var mask uint64
switch raw.Action {
case syscall.FILE_ACTION_REMOVED:
mask = sysFSDELETESELF
case syscall.FILE_ACTION_MODIFIED:
mask = sysFSMODIFY
case syscall.FILE_ACTION_RENAMED_OLD_NAME:
watch.rename = name
case syscall.FILE_ACTION_RENAMED_NEW_NAME:
if watch.names[watch.rename] != 0 {
watch.names[name] |= watch.names[watch.rename]
delete(watch.names, watch.rename)
mask = sysFSMOVESELF
}
}
sendNameEvent := func() {
if w.sendEvent(fullname, watch.names[name]&mask) {
if watch.names[name]&sysFSONESHOT != 0 {
delete(watch.names, name)
}
}
}
if raw.Action != syscall.FILE_ACTION_RENAMED_NEW_NAME {
sendNameEvent()
}
if raw.Action == syscall.FILE_ACTION_REMOVED {
w.sendEvent(fullname, watch.names[name]&sysFSIGNORED)
delete(watch.names, name)
}
if w.sendEvent(fullname, watch.mask&toFSnotifyFlags(raw.Action)) {
if watch.mask&sysFSONESHOT != 0 {
watch.mask = 0
}
}
if raw.Action == syscall.FILE_ACTION_RENAMED_NEW_NAME {
fullname = filepath.Join(watch.path, watch.rename)
sendNameEvent()
}
// Move to the next event in the buffer
if raw.NextEntryOffset == 0 {
break
}
offset += raw.NextEntryOffset
// Error!
if offset >= n {
w.Errors <- errors.New("Windows system assumed buffer larger than it is, events have likely been missed.")
break
}
}
if err := w.startRead(watch); err != nil {
w.Errors <- err
}
}
}
func (w *Watcher) sendEvent(name string, mask uint64) bool {
if mask == 0 {
return false
}
event := newEvent(name, uint32(mask))
select {
case ch := <-w.quit:
w.quit <- ch
case w.Events <- event:
}
return true
}
func toWindowsFlags(mask uint64) uint32 {
var m uint32
if mask&sysFSACCESS != 0 {
m |= syscall.FILE_NOTIFY_CHANGE_LAST_ACCESS
}
if mask&sysFSMODIFY != 0 {
m |= syscall.FILE_NOTIFY_CHANGE_LAST_WRITE
}
if mask&sysFSATTRIB != 0 {
m |= syscall.FILE_NOTIFY_CHANGE_ATTRIBUTES
}
if mask&(sysFSMOVE|sysFSCREATE|sysFSDELETE) != 0 {
m |= syscall.FILE_NOTIFY_CHANGE_FILE_NAME | syscall.FILE_NOTIFY_CHANGE_DIR_NAME
}
return m
}
func toFSnotifyFlags(action uint32) uint64 {
switch action {
case syscall.FILE_ACTION_ADDED:
return sysFSCREATE
case syscall.FILE_ACTION_REMOVED:
return sysFSDELETE
case syscall.FILE_ACTION_MODIFIED:
return sysFSMODIFY
case syscall.FILE_ACTION_RENAMED_OLD_NAME:
return sysFSMOVEDFROM
case syscall.FILE_ACTION_RENAMED_NEW_NAME:
return sysFSMOVEDTO
}
return 0
}