;;; filenotify.el --- watch files for changes on disk -*- lexical-binding:t -*-
-;; Copyright (C) 2013-2015 Free Software Foundation, Inc.
+;; Copyright (C) 2013-2016 Free Software Foundation, Inc.
;; Author: Michael Albinus <michael.albinus@gmx.de>
;;; Commentary
;; This package is an abstraction layer from the different low-level
-;; file notification packages `gfilenotify', `inotify' and
+;; file notification packages `inotify', `kqueue', `gfilenotify' and
;; `w32notify'.
;;; Code:
+(require 'cl-lib)
+
(defconst file-notify--library
(cond
- ((featurep 'gfilenotify) 'gfilenotify)
((featurep 'inotify) 'inotify)
+ ((featurep 'kqueue) 'kqueue)
+ ((featurep 'gfilenotify) 'gfilenotify)
((featurep 'w32notify) 'w32notify))
"Non-nil when Emacs has been compiled with file notification support.
The value is the name of the low-level file notification package
(defvar file-notify-descriptors (make-hash-table :test 'equal)
"Hash table for registered file notification descriptors.
A key in this hash table is the descriptor as returned from
-`gfilenotify', `inotify', `w32notify' or a file name handler.
-The value in the hash table is a list
+`inotify', `kqueue', `gfilenotify', `w32notify' or a file name
+handler. The value in the hash table is a list
(DIR (FILE . CALLBACK) (FILE . CALLBACK) ...)
DESCRIPTOR should be an object returned by `file-notify-add-watch'.
If it is registered in `file-notify-descriptors', a stopped event is sent."
(let* ((desc (if (consp descriptor) (car descriptor) descriptor))
- (file (if (consp descriptor) (cdr descriptor)))
(registered (gethash desc file-notify-descriptors))
+ (file (if (consp descriptor) (cdr descriptor) (cl-caadr registered)))
(dir (car registered)))
(when (consp registered)
;; Send `stopped' event.
- (dolist (entry (cdr registered))
- (funcall (cdr entry)
- `(,(file-notify--descriptor desc) stopped
- ,(or (and (stringp (car entry))
- (expand-file-name (car entry) dir))
- dir))))
+ (funcall
+ (cdr (assoc file (cdr registered)))
+ `(,descriptor stopped ,(if file (expand-file-name file dir) dir)))
;; Modify `file-notify-descriptors'.
(if (not file)
- (remhash desc file-notify-descriptors)
- (setcdr registered
- (delete (assoc file (cdr registered)) (cdr registered)))
- (if (null (cdr registered))
- (remhash desc file-notify-descriptors)
- (puthash desc registered file-notify-descriptors))))))
-
-;; This function is used by `gfilenotify', `inotify' and `w32notify' events.
+ (remhash desc file-notify-descriptors)
+ (setcdr registered
+ (delete (assoc file (cdr registered)) (cdr registered)))
+ (if (null (cdr registered))
+ (remhash desc file-notify-descriptors)
+ (puthash desc registered file-notify-descriptors))))))
+
+;; This function is used by `inotify', `kqueue', `gfilenotify' and
+;; `w32notify' events.
;;;###autoload
(defun file-notify-handle-event (event)
"Handle file system monitoring event.
Otherwise, signal a `file-notify-error'."
(interactive "e")
+ ;;(message "file-notify-handle-event %S" event)
(if (and (eq (car event) 'file-notify)
(>= (length event) 3))
(funcall (nth 2 event) (nth 1 event))
"A pending file notification events for a future `renamed' action.
It is a form ((DESCRIPTOR ACTION FILE [FILE1-OR-COOKIE]) CALLBACK).")
+(defun file-notify--event-watched-file (event)
+ "Return file or directory being watched.
+Could be different from the directory watched by the backend library."
+ (let* ((desc (if (consp (car event)) (caar event) (car event)))
+ (registered (gethash desc file-notify-descriptors))
+ (file (if (consp (car event)) (cdar event) (cl-caadr registered)))
+ (dir (car registered)))
+ (if file (expand-file-name file dir) dir)))
+
(defun file-notify--event-file-name (event)
"Return file name of file notification event, or nil."
- (expand-file-name
- (or (and (stringp (nth 2 event)) (nth 2 event)) "")
- (car (gethash (car event) file-notify-descriptors))))
+ (directory-file-name
+ (expand-file-name
+ (or (and (stringp (nth 2 event)) (nth 2 event)) "")
+ (car (gethash (car event) file-notify-descriptors)))))
;; Only `gfilenotify' could return two file names.
(defun file-notify--event-file1-name (event)
"Return second file name of file notification event, or nil.
This is available in case a file has been moved."
(and (stringp (nth 3 event))
- (expand-file-name
- (nth 3 event) (car (gethash (car event) file-notify-descriptors)))))
+ (directory-file-name
+ (expand-file-name
+ (nth 3 event) (car (gethash (car event) file-notify-descriptors))))))
;; Cookies are offered by `inotify' only.
(defun file-notify--event-cookie (event)
;; `inotify' returns the same descriptor when the file (directory)
;; uses the same inode. We want to distinguish, and apply a virtual
;; descriptor which make the difference.
-(defun file-notify--descriptor (descriptor)
+(defun file-notify--descriptor (desc file)
"Return the descriptor to be used in `file-notify-*-watch'.
For `gfilenotify' and `w32notify' it is the same descriptor as
used in the low-level file notification package."
- (if (and (natnump descriptor) (eq file-notify--library 'inotify))
- (cons descriptor
- (car (cadr (gethash descriptor file-notify-descriptors))))
- descriptor))
+ (if (and (natnump desc) (eq file-notify--library 'inotify))
+ (cons desc
+ (and (stringp file)
+ (car (assoc
+ (file-name-nondirectory file)
+ (gethash desc file-notify-descriptors)))))
+ desc))
;; The callback function used to map between specific flags of the
;; respective file notifications, and the ones we return.
(setq actions nil))
;; Loop over actions. In fact, more than one action happens only
- ;; for `inotify'.
+ ;; for `inotify' and `kqueue'.
(dolist (action actions)
;; Send pending event, if it doesn't match.
;; Map action. We ignore all events which cannot be mapped.
(setq action
(cond
- ;; gfilenotify.
- ((memq action '(attribute-changed changed created deleted))
+ ((memq action
+ '(attribute-changed changed created deleted renamed))
action)
- ((eq action 'moved)
- (setq file1 (file-notify--event-file1-name event))
- 'renamed)
-
- ;; inotify, w32notify.
+ ((memq action '(moved rename))
+ ;; The kqueue rename event does not return file1 in
+ ;; case a file monitor is established.
+ (if (setq file1 (file-notify--event-file1-name event))
+ 'renamed 'deleted))
((eq action 'ignored)
(setq stopped t actions nil))
- ((eq action 'attrib) 'attribute-changed)
+ ((memq action '(attrib link)) 'attribute-changed)
((memq action '(create added)) 'created)
- ((memq action '(modify modified)) 'changed)
+ ((memq action '(modify modified write)) 'changed)
((memq action '(delete delete-self move-self removed)) 'deleted)
;; Make the event pending.
((memq action '(moved-from renamed-from))
(car file-notify--pending-event)))
;; If the source is handled by another watch, we
;; must fire the rename event there as well.
- (when (not (equal (file-notify--descriptor desc)
+ (when (not (equal (file-notify--descriptor desc file1)
(file-notify--descriptor
- (caar file-notify--pending-event))))
+ (caar file-notify--pending-event)
+ (file-notify--event-file-name
+ file-notify--pending-event))))
(setq pending-event
`((,(caar file-notify--pending-event)
renamed ,file ,file1)
;; Apply pending callback.
(when pending-event
(setcar
- (car pending-event) (file-notify--descriptor (caar pending-event)))
+ (car pending-event)
+ (file-notify--descriptor
+ (caar pending-event)
+ (file-notify--event-file-name file-notify--pending-event)))
(funcall (cadr pending-event) (car pending-event))
(setq pending-event nil))
- ;; Check for stopped.
- (setq
- stopped
- (or
- stopped
- (and
- (memq action '(deleted renamed))
- (= (length (cdr registered)) 1)
- (string-equal
- (or (file-name-nondirectory file) "") (car (cadr registered))))))
-
;; Apply callback.
(when (and action
(or
;; File matches.
(string-equal
(nth 0 entry) (file-name-nondirectory file))
+ ;; Directory matches.
+ (string-equal
+ (file-name-nondirectory file)
+ (file-name-nondirectory (car registered)))
;; File1 matches.
(and (stringp file1)
(string-equal
(nth 0 entry) (file-name-nondirectory file1)))))
+ ;;(message
+ ;;"file-notify-callback %S %S %S %S %S"
+ ;;(file-notify--descriptor desc (car entry))
+ ;;action file file1 registered)
(if file1
(funcall
callback
- `(,(file-notify--descriptor desc) ,action ,file ,file1))
+ `(,(file-notify--descriptor desc (car entry))
+ ,action ,file ,file1))
(funcall
callback
- `(,(file-notify--descriptor desc) ,action ,file)))))
-
- ;; Modify `file-notify-descriptors'.
- (when stopped
- (file-notify--rm-descriptor (file-notify--descriptor desc))))))
-
-;; `gfilenotify' and `w32notify' return a unique descriptor for every
-;; `file-notify-add-watch', while `inotify' returns a unique
+ `(,(file-notify--descriptor desc (car entry)) ,action ,file))))
+
+ ;; Send `stopped' event.
+ (when (or stopped
+ (and (memq action '(deleted renamed))
+ ;; Not, when a file is backed up.
+ (not (and (stringp file1) (backup-file-name-p file1)))
+ ;; Watched file or directory is concerned.
+ (string-equal
+ file (file-notify--event-watched-file event))))
+ (file-notify-rm-watch (file-notify--descriptor desc (car entry))))))))
+
+;; `kqueue', `gfilenotify' and `w32notify' return a unique descriptor
+;; for every `file-notify-add-watch', while `inotify' returns a unique
;; descriptor per inode only.
(defun file-notify-add-watch (file flags callback)
"Add a watch for filesystem events pertaining to FILE.
(if (file-directory-p file)
file
(file-name-directory file))))
- desc func l-flags registered)
+ desc func l-flags registered entry)
(unless (file-directory-p dir)
(signal 'file-notify-error `("Directory does not exist" ,dir)))
;; A file name handler could exist even if there is no local
;; file notification support.
(setq desc (funcall
- handler 'file-notify-add-watch dir flags callback))
-
- ;; Check, whether Emacs has been compiled with file
- ;; notification support.
+ handler 'file-notify-add-watch
+ ;; kqueue does not report file changes in
+ ;; directory monitor. So we must watch the file
+ ;; itself.
+ (if (eq file-notify--library 'kqueue) file dir)
+ flags callback))
+
+ ;; Check, whether Emacs has been compiled with file notification
+ ;; support.
(unless file-notify--library
(signal 'file-notify-error
'("No file notification package available")))
;; Determine low-level function to be called.
(setq func
(cond
- ((eq file-notify--library 'gfilenotify) 'gfile-add-watch)
((eq file-notify--library 'inotify) 'inotify-add-watch)
+ ((eq file-notify--library 'kqueue) 'kqueue-add-watch)
+ ((eq file-notify--library 'gfilenotify) 'gfile-add-watch)
((eq file-notify--library 'w32notify) 'w32notify-add-watch)))
;; Determine respective flags.
(setq
l-flags
(cond
- ((eq file-notify--library 'inotify) '(create modify move delete))
+ ((eq file-notify--library 'inotify)
+ '(create delete delete-self modify move-self move))
+ ((eq file-notify--library 'kqueue)
+ '(create delete write extend rename))
((eq file-notify--library 'w32notify)
'(file-name directory-name size last-write-time)))))
(when (memq 'attribute-change flags)
(push (cond
((eq file-notify--library 'inotify) 'attrib)
+ ((eq file-notify--library 'kqueue) 'attrib)
((eq file-notify--library 'w32notify) 'attributes))
l-flags)))
;; Call low-level function.
- (setq desc (funcall func dir l-flags 'file-notify-callback)))
+ (setq desc (funcall
+ func (if (eq file-notify--library 'kqueue) file dir)
+ l-flags 'file-notify-callback)))
;; Modify `file-notify-descriptors'.
- (setq registered (gethash desc file-notify-descriptors))
- (puthash
- desc
- `(,dir
- (,(unless (file-directory-p file) (file-name-nondirectory file))
- . ,callback)
- . ,(cdr registered))
- file-notify-descriptors)
+ (setq file (unless (file-directory-p file) (file-name-nondirectory file))
+ desc (if (consp desc) (car desc) desc)
+ registered (gethash desc file-notify-descriptors)
+ entry `(,file . ,callback))
+ (unless (member entry (cdr registered))
+ (puthash desc `(,dir ,entry . ,(cdr registered)) file-notify-descriptors))
;; Return descriptor.
- (file-notify--descriptor desc)))
+ (file-notify--descriptor desc file)))
(defun file-notify-rm-watch (descriptor)
"Remove an existing watch specified by its DESCRIPTOR.
(if handler
;; A file name handler could exist even if there is no local
;; file notification support.
- (funcall handler 'file-notify-rm-watch desc)
+ (funcall handler 'file-notify-rm-watch descriptor)
(funcall
(cond
- ((eq file-notify--library 'gfilenotify) 'gfile-rm-watch)
((eq file-notify--library 'inotify) 'inotify-rm-watch)
+ ((eq file-notify--library 'kqueue) 'kqueue-rm-watch)
+ ((eq file-notify--library 'gfilenotify) 'gfile-rm-watch)
((eq file-notify--library 'w32notify) 'w32notify-rm-watch))
desc))
(file-notify-error nil)))
(funcall handler 'file-notify-valid-p descriptor)
(funcall
(cond
- ((eq file-notify--library 'gfilenotify) 'gfile-valid-p)
((eq file-notify--library 'inotify) 'inotify-valid-p)
+ ((eq file-notify--library 'kqueue) 'kqueue-valid-p)
+ ((eq file-notify--library 'gfilenotify) 'gfile-valid-p)
((eq file-notify--library 'w32notify) 'w32notify-valid-p))
desc))
t))))