summaryrefslogtreecommitdiff
path: root/vendor/gopkg.in/fsnotify.v1/windows.go
diff options
context:
space:
mode:
Diffstat (limited to 'vendor/gopkg.in/fsnotify.v1/windows.go')
-rw-r--r--vendor/gopkg.in/fsnotify.v1/windows.go561
1 files changed, 561 insertions, 0 deletions
diff --git a/vendor/gopkg.in/fsnotify.v1/windows.go b/vendor/gopkg.in/fsnotify.v1/windows.go
new file mode 100644
index 000000000..09436f31d
--- /dev/null
+++ b/vendor/gopkg.in/fsnotify.v1/windows.go
@@ -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
+}
generated by cgit v1.2.3-54-g00ecf (git 2.39.0) at 2024-11-07 16:32:20 +0000