828 lines
23 KiB
Go
828 lines
23 KiB
Go
//go:build windows
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// +build windows
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// Windows backend based on ReadDirectoryChangesW()
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//
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// https://learn.microsoft.com/en-us/windows/win32/api/winbase/nf-winbase-readdirectorychangesw
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//
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// Note: the documentation on the Watcher type and methods is generated from
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// mkdoc.zsh
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package fsnotify
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import (
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"errors"
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"fmt"
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"os"
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"path/filepath"
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"reflect"
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"runtime"
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"strings"
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"sync"
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"unsafe"
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"golang.org/x/sys/windows"
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)
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// Watcher watches a set of paths, delivering events on a channel.
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//
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// A watcher should not be copied (e.g. pass it by pointer, rather than by
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// value).
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//
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// # Linux notes
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//
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// When a file is removed a Remove event won't be emitted until all file
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// descriptors are closed, and deletes will always emit a Chmod. For example:
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//
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// fp := os.Open("file")
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// os.Remove("file") // Triggers Chmod
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// fp.Close() // Triggers Remove
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//
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// This is the event that inotify sends, so not much can be changed about this.
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//
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// The fs.inotify.max_user_watches sysctl variable specifies the upper limit
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// for the number of watches per user, and fs.inotify.max_user_instances
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// specifies the maximum number of inotify instances per user. Every Watcher you
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// create is an "instance", and every path you add is a "watch".
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//
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// These are also exposed in /proc as /proc/sys/fs/inotify/max_user_watches and
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// /proc/sys/fs/inotify/max_user_instances
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//
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// To increase them you can use sysctl or write the value to the /proc file:
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//
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// # Default values on Linux 5.18
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// sysctl fs.inotify.max_user_watches=124983
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// sysctl fs.inotify.max_user_instances=128
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//
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// To make the changes persist on reboot edit /etc/sysctl.conf or
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// /usr/lib/sysctl.d/50-default.conf (details differ per Linux distro; check
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// your distro's documentation):
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//
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// fs.inotify.max_user_watches=124983
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// fs.inotify.max_user_instances=128
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//
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// Reaching the limit will result in a "no space left on device" or "too many open
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// files" error.
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//
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// # kqueue notes (macOS, BSD)
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//
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// kqueue requires opening a file descriptor for every file that's being watched;
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// so if you're watching a directory with five files then that's six file
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// descriptors. You will run in to your system's "max open files" limit faster on
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// these platforms.
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//
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// The sysctl variables kern.maxfiles and kern.maxfilesperproc can be used to
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// control the maximum number of open files, as well as /etc/login.conf on BSD
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// systems.
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//
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// # Windows notes
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//
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// Paths can be added as "C:\path\to\dir", but forward slashes
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// ("C:/path/to/dir") will also work.
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//
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// When a watched directory is removed it will always send an event for the
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// directory itself, but may not send events for all files in that directory.
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// Sometimes it will send events for all times, sometimes it will send no
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// events, and often only for some files.
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//
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// The default ReadDirectoryChangesW() buffer size is 64K, which is the largest
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// value that is guaranteed to work with SMB filesystems. If you have many
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// events in quick succession this may not be enough, and you will have to use
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// [WithBufferSize] to increase the value.
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type Watcher struct {
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// Events sends the filesystem change events.
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//
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// fsnotify can send the following events; a "path" here can refer to a
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// file, directory, symbolic link, or special file like a FIFO.
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//
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// fsnotify.Create A new path was created; this may be followed by one
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// or more Write events if data also gets written to a
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// file.
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//
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// fsnotify.Remove A path was removed.
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//
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// fsnotify.Rename A path was renamed. A rename is always sent with the
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// old path as Event.Name, and a Create event will be
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// sent with the new name. Renames are only sent for
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// paths that are currently watched; e.g. moving an
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// unmonitored file into a monitored directory will
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// show up as just a Create. Similarly, renaming a file
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// to outside a monitored directory will show up as
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// only a Rename.
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//
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// fsnotify.Write A file or named pipe was written to. A Truncate will
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// also trigger a Write. A single "write action"
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// initiated by the user may show up as one or multiple
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// writes, depending on when the system syncs things to
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// disk. For example when compiling a large Go program
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// you may get hundreds of Write events, and you may
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// want to wait until you've stopped receiving them
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// (see the dedup example in cmd/fsnotify).
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//
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// Some systems may send Write event for directories
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// when the directory content changes.
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//
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// fsnotify.Chmod Attributes were changed. On Linux this is also sent
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// when a file is removed (or more accurately, when a
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// link to an inode is removed). On kqueue it's sent
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// when a file is truncated. On Windows it's never
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// sent.
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Events chan Event
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// Errors sends any errors.
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//
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// ErrEventOverflow is used to indicate there are too many events:
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//
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// - inotify: There are too many queued events (fs.inotify.max_queued_events sysctl)
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// - windows: The buffer size is too small; WithBufferSize() can be used to increase it.
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// - kqueue, fen: Not used.
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Errors chan error
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port windows.Handle // Handle to completion port
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input chan *input // Inputs to the reader are sent on this channel
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quit chan chan<- error
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mu sync.Mutex // Protects access to watches, closed
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watches watchMap // Map of watches (key: i-number)
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closed bool // Set to true when Close() is first called
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}
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// NewWatcher creates a new Watcher.
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func NewWatcher() (*Watcher, error) {
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return NewBufferedWatcher(50)
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}
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// NewBufferedWatcher creates a new Watcher with a buffered Watcher.Events
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// channel.
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//
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// The main use case for this is situations with a very large number of events
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// where the kernel buffer size can't be increased (e.g. due to lack of
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// permissions). An unbuffered Watcher will perform better for almost all use
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// cases, and whenever possible you will be better off increasing the kernel
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// buffers instead of adding a large userspace buffer.
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func NewBufferedWatcher(sz uint) (*Watcher, error) {
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port, err := windows.CreateIoCompletionPort(windows.InvalidHandle, 0, 0, 0)
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if err != nil {
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return nil, os.NewSyscallError("CreateIoCompletionPort", err)
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}
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w := &Watcher{
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port: port,
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watches: make(watchMap),
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input: make(chan *input, 1),
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Events: make(chan Event, sz),
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Errors: make(chan error),
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quit: make(chan chan<- error, 1),
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}
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go w.readEvents()
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return w, nil
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}
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func (w *Watcher) isClosed() bool {
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w.mu.Lock()
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defer w.mu.Unlock()
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return w.closed
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}
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func (w *Watcher) sendEvent(name string, mask uint64) bool {
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if mask == 0 {
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return false
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}
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event := w.newEvent(name, uint32(mask))
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select {
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case ch := <-w.quit:
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w.quit <- ch
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case w.Events <- event:
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}
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return true
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}
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// Returns true if the error was sent, or false if watcher is closed.
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func (w *Watcher) sendError(err error) bool {
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select {
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case w.Errors <- err:
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return true
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case <-w.quit:
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}
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return false
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}
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// Close removes all watches and closes the Events channel.
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func (w *Watcher) Close() error {
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if w.isClosed() {
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return nil
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}
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w.mu.Lock()
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w.closed = true
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w.mu.Unlock()
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// Send "quit" message to the reader goroutine
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ch := make(chan error)
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w.quit <- ch
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if err := w.wakeupReader(); err != nil {
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return err
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}
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return <-ch
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}
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// Add starts monitoring the path for changes.
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//
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// A path can only be watched once; watching it more than once is a no-op and will
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// not return an error. Paths that do not yet exist on the filesystem cannot be
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// watched.
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//
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// A watch will be automatically removed if the watched path is deleted or
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// renamed. The exception is the Windows backend, which doesn't remove the
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// watcher on renames.
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//
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// Notifications on network filesystems (NFS, SMB, FUSE, etc.) or special
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// filesystems (/proc, /sys, etc.) generally don't work.
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//
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// Returns [ErrClosed] if [Watcher.Close] was called.
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//
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// See [Watcher.AddWith] for a version that allows adding options.
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//
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// # Watching directories
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//
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// All files in a directory are monitored, including new files that are created
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// after the watcher is started. Subdirectories are not watched (i.e. it's
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// non-recursive).
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//
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// # Watching files
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//
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// Watching individual files (rather than directories) is generally not
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// recommended as many programs (especially editors) update files atomically: it
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// will write to a temporary file which is then moved to to destination,
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// overwriting the original (or some variant thereof). The watcher on the
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// original file is now lost, as that no longer exists.
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//
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// The upshot of this is that a power failure or crash won't leave a
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// half-written file.
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//
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// Watch the parent directory and use Event.Name to filter out files you're not
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// interested in. There is an example of this in cmd/fsnotify/file.go.
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func (w *Watcher) Add(name string) error { return w.AddWith(name) }
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// AddWith is like [Watcher.Add], but allows adding options. When using Add()
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// the defaults described below are used.
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//
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// Possible options are:
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//
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// - [WithBufferSize] sets the buffer size for the Windows backend; no-op on
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// other platforms. The default is 64K (65536 bytes).
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func (w *Watcher) AddWith(name string, opts ...addOpt) error {
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if w.isClosed() {
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return ErrClosed
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}
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with := getOptions(opts...)
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if with.bufsize < 4096 {
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return fmt.Errorf("fsnotify.WithBufferSize: buffer size cannot be smaller than 4096 bytes")
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}
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in := &input{
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op: opAddWatch,
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path: filepath.Clean(name),
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flags: sysFSALLEVENTS,
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reply: make(chan error),
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bufsize: with.bufsize,
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}
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w.input <- in
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if err := w.wakeupReader(); err != nil {
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return err
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}
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return <-in.reply
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}
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// Remove stops monitoring the path for changes.
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//
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// Directories are always removed non-recursively. For example, if you added
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// /tmp/dir and /tmp/dir/subdir then you will need to remove both.
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//
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// Removing a path that has not yet been added returns [ErrNonExistentWatch].
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//
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// Returns nil if [Watcher.Close] was called.
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func (w *Watcher) Remove(name string) error {
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if w.isClosed() {
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return nil
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}
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in := &input{
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op: opRemoveWatch,
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path: filepath.Clean(name),
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reply: make(chan error),
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}
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w.input <- in
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if err := w.wakeupReader(); err != nil {
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return err
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}
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return <-in.reply
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}
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// WatchList returns all paths explicitly added with [Watcher.Add] (and are not
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// yet removed).
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//
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// Returns nil if [Watcher.Close] was called.
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func (w *Watcher) WatchList() []string {
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if w.isClosed() {
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return nil
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}
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w.mu.Lock()
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defer w.mu.Unlock()
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entries := make([]string, 0, len(w.watches))
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for _, entry := range w.watches {
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for _, watchEntry := range entry {
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entries = append(entries, watchEntry.path)
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}
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}
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return entries
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}
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// These options are from the old golang.org/x/exp/winfsnotify, where you could
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// add various options to the watch. This has long since been removed.
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//
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// The "sys" in the name is misleading as they're not part of any "system".
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//
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// This should all be removed at some point, and just use windows.FILE_NOTIFY_*
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const (
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sysFSALLEVENTS = 0xfff
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sysFSCREATE = 0x100
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sysFSDELETE = 0x200
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sysFSDELETESELF = 0x400
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sysFSMODIFY = 0x2
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sysFSMOVE = 0xc0
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sysFSMOVEDFROM = 0x40
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sysFSMOVEDTO = 0x80
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sysFSMOVESELF = 0x800
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sysFSIGNORED = 0x8000
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)
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func (w *Watcher) newEvent(name string, mask uint32) Event {
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e := Event{Name: name}
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if mask&sysFSCREATE == sysFSCREATE || mask&sysFSMOVEDTO == sysFSMOVEDTO {
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e.Op |= Create
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}
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if mask&sysFSDELETE == sysFSDELETE || mask&sysFSDELETESELF == sysFSDELETESELF {
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e.Op |= Remove
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}
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if mask&sysFSMODIFY == sysFSMODIFY {
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e.Op |= Write
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}
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if mask&sysFSMOVE == sysFSMOVE || mask&sysFSMOVESELF == sysFSMOVESELF || mask&sysFSMOVEDFROM == sysFSMOVEDFROM {
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e.Op |= Rename
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}
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return e
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}
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const (
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opAddWatch = iota
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opRemoveWatch
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)
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const (
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provisional uint64 = 1 << (32 + iota)
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)
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type input struct {
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op int
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path string
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flags uint32
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bufsize int
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reply chan error
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}
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type inode struct {
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handle windows.Handle
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volume uint32
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index uint64
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}
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type watch struct {
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ov windows.Overlapped
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ino *inode // i-number
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recurse bool // Recursive watch?
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path string // Directory path
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mask uint64 // Directory itself is being watched with these notify flags
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names map[string]uint64 // Map of names being watched and their notify flags
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rename string // Remembers the old name while renaming a file
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buf []byte // buffer, allocated later
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}
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type (
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indexMap map[uint64]*watch
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watchMap map[uint32]indexMap
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)
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func (w *Watcher) wakeupReader() error {
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err := windows.PostQueuedCompletionStatus(w.port, 0, 0, nil)
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if err != nil {
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return os.NewSyscallError("PostQueuedCompletionStatus", err)
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}
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return nil
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}
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func (w *Watcher) getDir(pathname string) (dir string, err error) {
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attr, err := windows.GetFileAttributes(windows.StringToUTF16Ptr(pathname))
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if err != nil {
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return "", os.NewSyscallError("GetFileAttributes", err)
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}
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if attr&windows.FILE_ATTRIBUTE_DIRECTORY != 0 {
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dir = pathname
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} else {
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dir, _ = filepath.Split(pathname)
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dir = filepath.Clean(dir)
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}
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return
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}
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func (w *Watcher) getIno(path string) (ino *inode, err error) {
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h, err := windows.CreateFile(windows.StringToUTF16Ptr(path),
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windows.FILE_LIST_DIRECTORY,
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windows.FILE_SHARE_READ|windows.FILE_SHARE_WRITE|windows.FILE_SHARE_DELETE,
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nil, windows.OPEN_EXISTING,
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windows.FILE_FLAG_BACKUP_SEMANTICS|windows.FILE_FLAG_OVERLAPPED, 0)
|
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if err != nil {
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return nil, os.NewSyscallError("CreateFile", err)
|
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}
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var fi windows.ByHandleFileInformation
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err = windows.GetFileInformationByHandle(h, &fi)
|
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if err != nil {
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windows.CloseHandle(h)
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return nil, os.NewSyscallError("GetFileInformationByHandle", err)
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}
|
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ino = &inode{
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handle: h,
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volume: fi.VolumeSerialNumber,
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index: uint64(fi.FileIndexHigh)<<32 | uint64(fi.FileIndexLow),
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}
|
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return ino, nil
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|
}
|
|
|
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// Must run within the I/O thread.
|
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func (m watchMap) get(ino *inode) *watch {
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if i := m[ino.volume]; i != nil {
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return i[ino.index]
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}
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return nil
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}
|
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|
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// Must run within the I/O thread.
|
|
func (m watchMap) set(ino *inode, watch *watch) {
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i := m[ino.volume]
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if i == nil {
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i = make(indexMap)
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m[ino.volume] = i
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}
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i[ino.index] = watch
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}
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|
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// Must run within the I/O thread.
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func (w *Watcher) addWatch(pathname string, flags uint64, bufsize int) error {
|
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//pathname, recurse := recursivePath(pathname)
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recurse := false
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dir, err := w.getDir(pathname)
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if err != nil {
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return err
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}
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ino, err := w.getIno(dir)
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if err != nil {
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return err
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}
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w.mu.Lock()
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watchEntry := w.watches.get(ino)
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w.mu.Unlock()
|
|
if watchEntry == nil {
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_, err := windows.CreateIoCompletionPort(ino.handle, w.port, 0, 0)
|
|
if err != nil {
|
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windows.CloseHandle(ino.handle)
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return os.NewSyscallError("CreateIoCompletionPort", err)
|
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}
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watchEntry = &watch{
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ino: ino,
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path: dir,
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names: make(map[string]uint64),
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recurse: recurse,
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buf: make([]byte, bufsize),
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}
|
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w.mu.Lock()
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w.watches.set(ino, watchEntry)
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w.mu.Unlock()
|
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flags |= provisional
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} else {
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windows.CloseHandle(ino.handle)
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}
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if pathname == dir {
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watchEntry.mask |= flags
|
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} else {
|
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watchEntry.names[filepath.Base(pathname)] |= flags
|
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}
|
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|
|
err = w.startRead(watchEntry)
|
|
if 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 {
|
|
pathname, recurse := recursivePath(pathname)
|
|
|
|
dir, err := w.getDir(pathname)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
ino, err := w.getIno(dir)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
w.mu.Lock()
|
|
watch := w.watches.get(ino)
|
|
w.mu.Unlock()
|
|
|
|
if recurse && !watch.recurse {
|
|
return fmt.Errorf("can't use \\... with non-recursive watch %q", pathname)
|
|
}
|
|
|
|
err = windows.CloseHandle(ino.handle)
|
|
if err != nil {
|
|
w.sendError(os.NewSyscallError("CloseHandle", err))
|
|
}
|
|
if watch == nil {
|
|
return fmt.Errorf("%w: %s", ErrNonExistentWatch, 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 {
|
|
err := windows.CancelIo(watch.ino.handle)
|
|
if err != nil {
|
|
w.sendError(os.NewSyscallError("CancelIo", err))
|
|
w.deleteWatch(watch)
|
|
}
|
|
mask := w.toWindowsFlags(watch.mask)
|
|
for _, m := range watch.names {
|
|
mask |= w.toWindowsFlags(m)
|
|
}
|
|
if mask == 0 {
|
|
err := windows.CloseHandle(watch.ino.handle)
|
|
if err != nil {
|
|
w.sendError(os.NewSyscallError("CloseHandle", err))
|
|
}
|
|
w.mu.Lock()
|
|
delete(w.watches[watch.ino.volume], watch.ino.index)
|
|
w.mu.Unlock()
|
|
return nil
|
|
}
|
|
|
|
// We need to pass the array, rather than the slice.
|
|
hdr := (*reflect.SliceHeader)(unsafe.Pointer(&watch.buf))
|
|
rdErr := windows.ReadDirectoryChanges(watch.ino.handle,
|
|
(*byte)(unsafe.Pointer(hdr.Data)), uint32(hdr.Len),
|
|
watch.recurse, mask, nil, &watch.ov, 0)
|
|
if rdErr != nil {
|
|
err := os.NewSyscallError("ReadDirectoryChanges", rdErr)
|
|
if rdErr == windows.ERROR_ACCESS_DENIED && watch.mask&provisional == 0 {
|
|
// Watched directory was probably removed
|
|
w.sendEvent(watch.path, watch.mask&sysFSDELETESELF)
|
|
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 uint32
|
|
key uintptr
|
|
ov *windows.Overlapped
|
|
)
|
|
runtime.LockOSThread()
|
|
|
|
for {
|
|
// This error is handled after the watch == nil check below.
|
|
qErr := windows.GetQueuedCompletionStatus(w.port, &n, &key, &ov, windows.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)
|
|
}
|
|
}
|
|
|
|
err := windows.CloseHandle(w.port)
|
|
if err != nil {
|
|
err = os.NewSyscallError("CloseHandle", err)
|
|
}
|
|
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), in.bufsize)
|
|
case opRemoveWatch:
|
|
in.reply <- w.remWatch(in.path)
|
|
}
|
|
default:
|
|
}
|
|
continue
|
|
}
|
|
|
|
switch qErr {
|
|
case nil:
|
|
// No error
|
|
case windows.ERROR_MORE_DATA:
|
|
if watch == nil {
|
|
w.sendError(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 windows.ERROR_ACCESS_DENIED:
|
|
// Watched directory was probably removed
|
|
w.sendEvent(watch.path, watch.mask&sysFSDELETESELF)
|
|
w.deleteWatch(watch)
|
|
w.startRead(watch)
|
|
continue
|
|
case windows.ERROR_OPERATION_ABORTED:
|
|
// CancelIo was called on this handle
|
|
continue
|
|
default:
|
|
w.sendError(os.NewSyscallError("GetQueuedCompletionPort", qErr))
|
|
continue
|
|
}
|
|
|
|
var offset uint32
|
|
for {
|
|
if n == 0 {
|
|
w.sendError(ErrEventOverflow)
|
|
break
|
|
}
|
|
|
|
// Point "raw" to the event in the buffer
|
|
raw := (*windows.FileNotifyInformation)(unsafe.Pointer(&watch.buf[offset]))
|
|
|
|
// Create a buf that is the size of the path name
|
|
size := int(raw.FileNameLength / 2)
|
|
var buf []uint16
|
|
// TODO: Use unsafe.Slice in Go 1.17; https://stackoverflow.com/questions/51187973
|
|
sh := (*reflect.SliceHeader)(unsafe.Pointer(&buf))
|
|
sh.Data = uintptr(unsafe.Pointer(&raw.FileName))
|
|
sh.Len = size
|
|
sh.Cap = size
|
|
name := windows.UTF16ToString(buf)
|
|
fullname := filepath.Join(watch.path, name)
|
|
|
|
var mask uint64
|
|
switch raw.Action {
|
|
case windows.FILE_ACTION_REMOVED:
|
|
mask = sysFSDELETESELF
|
|
case windows.FILE_ACTION_MODIFIED:
|
|
mask = sysFSMODIFY
|
|
case windows.FILE_ACTION_RENAMED_OLD_NAME:
|
|
watch.rename = name
|
|
case windows.FILE_ACTION_RENAMED_NEW_NAME:
|
|
// Update saved path of all sub-watches.
|
|
old := filepath.Join(watch.path, watch.rename)
|
|
w.mu.Lock()
|
|
for _, watchMap := range w.watches {
|
|
for _, ww := range watchMap {
|
|
if strings.HasPrefix(ww.path, old) {
|
|
ww.path = filepath.Join(fullname, strings.TrimPrefix(ww.path, old))
|
|
}
|
|
}
|
|
}
|
|
w.mu.Unlock()
|
|
|
|
if watch.names[watch.rename] != 0 {
|
|
watch.names[name] |= watch.names[watch.rename]
|
|
delete(watch.names, watch.rename)
|
|
mask = sysFSMOVESELF
|
|
}
|
|
}
|
|
|
|
sendNameEvent := func() {
|
|
w.sendEvent(fullname, watch.names[name]&mask)
|
|
}
|
|
if raw.Action != windows.FILE_ACTION_RENAMED_NEW_NAME {
|
|
sendNameEvent()
|
|
}
|
|
if raw.Action == windows.FILE_ACTION_REMOVED {
|
|
w.sendEvent(fullname, watch.names[name]&sysFSIGNORED)
|
|
delete(watch.names, name)
|
|
}
|
|
|
|
w.sendEvent(fullname, watch.mask&w.toFSnotifyFlags(raw.Action))
|
|
if raw.Action == windows.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 {
|
|
//lint:ignore ST1005 Windows should be capitalized
|
|
w.sendError(errors.New(
|
|
"Windows system assumed buffer larger than it is, events have likely been missed"))
|
|
break
|
|
}
|
|
}
|
|
|
|
if err := w.startRead(watch); err != nil {
|
|
w.sendError(err)
|
|
}
|
|
}
|
|
}
|
|
|
|
func (w *Watcher) toWindowsFlags(mask uint64) uint32 {
|
|
var m uint32
|
|
if mask&sysFSMODIFY != 0 {
|
|
m |= windows.FILE_NOTIFY_CHANGE_LAST_WRITE
|
|
}
|
|
if mask&(sysFSMOVE|sysFSCREATE|sysFSDELETE) != 0 {
|
|
m |= windows.FILE_NOTIFY_CHANGE_FILE_NAME | windows.FILE_NOTIFY_CHANGE_DIR_NAME
|
|
}
|
|
return m
|
|
}
|
|
|
|
func (w *Watcher) toFSnotifyFlags(action uint32) uint64 {
|
|
switch action {
|
|
case windows.FILE_ACTION_ADDED:
|
|
return sysFSCREATE
|
|
case windows.FILE_ACTION_REMOVED:
|
|
return sysFSDELETE
|
|
case windows.FILE_ACTION_MODIFIED:
|
|
return sysFSMODIFY
|
|
case windows.FILE_ACTION_RENAMED_OLD_NAME:
|
|
return sysFSMOVEDFROM
|
|
case windows.FILE_ACTION_RENAMED_NEW_NAME:
|
|
return sysFSMOVEDTO
|
|
}
|
|
return 0
|
|
}
|