-(in-package #:cl-notify)
-
-(defbitfield (inotify-flags :uint32)
- (:in-access #.in-access)
- (:in-modify #.in-modify)
- (:in-attrib #.in-attrib)
- (:in-close-write #.in-close-write)
- (:in-close-nowrite #.in-close-nowrite)
- (:in-close #.in-close)
- (:in-open #.in-open)
- (:in-moved-from #.in-moved-from)
- (:in-moved-to #.in-moved-to)
- (:in-move #.in-move)
- (:in-create #.in-create)
- (:in-delete #.in-delete)
- (:in-delete-self #.in-delete-self)
- (:in-move-self #.in-move-self)
- (:in-unmount #.in-unmount)
- (:in-q-overflow #.in-q-overflow)
- (:in-ignored #.in-ignored)
- (:in-onlydir #.in-onlydir)
- (:in-dont-follow #.in-dont-follow)
- (:in-mask-add #.in-mask-add)
- (:in-isdir #.in-isdir)
- (:in-oneshot #.in-oneshot)
- (:in-all-events #.in-all-events))
-
-(defcfun "inotify_init" :int)
-
-(defcfun "inotify_add_watch" :int
+;;; -*- mode: lisp; syntax: common-lisp; coding: utf-8; package: cl-inotify; -*-
+
+;; Copyright (c) 2011, Olof-Joachim Frahm
+;; 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.
+;; * The name of the author may not 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 <COPYRIGHT HOLDER> 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.
+
+(in-package #:cl-inotify)
+
+(defbitfield (inotify-flag :uint32)
+ (:access #.in-access)
+ (:modify #.in-modify)
+ (:attrib #.in-attrib)
+ (:close-write #.in-close-write)
+ (:close-nowrite #.in-close-nowrite)
+ (:close #.in-close)
+ (:open #.in-open)
+ (:moved-from #.in-moved-from)
+ (:moved-to #.in-moved-to)
+ (:move #.in-move)
+ (:create #.in-create)
+ (:delete #.in-delete)
+ (:delete-self #.in-delete-self)
+ (:move-self #.in-move-self)
+ (:unmount #.in-unmount)
+ (:q-overflow #.in-q-overflow)
+ (:ignored #.in-ignored)
+ (:onlydir #.in-onlydir)
+ (:dont-follow #.in-dont-follow)
+ (:mask-add #.in-mask-add)
+ (:isdir #.in-isdir)
+ (:oneshot #.in-oneshot)
+ (:all-events #.in-all-events))
+
+(deftype inotify-add/read-flag ()
+ "Shared valid flags for the WATCH-RAW and READ-EVENT functions."
+ '(member
+ :access :attrib
+ :close-write :close-nowrite :close
+ :create :delete :delete-self
+ :modify
+ :move-self :moved-from :moved-to :move
+ :open :all-events))
+
+(deftype inotify-read-flag ()
+ "Valid flags which are returned from READ-EVENT."
+ '(or inotify-add/read-flag
+ (member :ignored :isdir :q-overflow :unmount)))
+
+(deftype inotify-add-flag ()
+ "Valid flags for the WATCH-RAW function."
+ '(or inotify-add/read-flag
+ (member :dont-follow :mask-add :oneshot :onlydir)))
+
+(defun valid-watch-flag-p (x)
+ (and (typep x 'inotify-add-flag)
+ (not (eq :mask-add x))
+ (not (eq :oneshot x))))
+
+(defun valid-watch-flag-list-p (list)
+ (every #'valid-watch-flag-p list))
+
+(deftype watch-flag-list ()
+ "Valid flags argument for the WATCH function, a list of keywords from
+INOTIFY-ADD-FLAG. Basically only :MASK-ADD and :ONESHOT are removed.
+The :MASK-ADD behaviour is replicated with the REPLACE-P argument; the
+:ONESHOT behaviour doesn't play well with the WATCH function design (and
+thus should be used only with WATCH-RAW)."
+ '(or (satisfies valid-watch-flag-p)
+ (and list (satisfies valid-watch-flag-list-p))))
+
+(defcfun ("inotify_init" c-inotify-init) :int
+ "Initialises a new inotify event queue.")
+
+(defcfun ("inotify_add_watch" c-inotify-add-watch) :int
+ "Watches a path on a event queue."
(fd :int)
(pathname :string)
- (mask inotify-flags))
+ (mask inotify-flag))
-(defcfun "inotify_rm_watch" :int
+(defcfun ("inotify_rm_watch" c-inotify-rm-watch) :int
+ "Removes a watched path from a event queue."
(fd :int)
(wd :int))
(binary-types:define-signed int #.(cffi:foreign-type-size :int))
(binary-types:define-binary-struct inotify-event ()
+ "An inotify native event structure.
+WD is the watch/file descriptor,
+MASK is the (parsed) combination of events,
+COOKIE is a unique integer which connects related events,
+NAME optionally identifies a file relative to a watched directory."
(wd 0 :binary-type int)
(mask 0 :binary-type binary-types:u32)
(cookie 0 :binary-type binary-types:u32)
(name NIL))
-(defstruct (inotify-instance (:constructor make-inotify-instance (fd stream)))
+(defstruct (inotify-instance
+ (:constructor make-inotify-instance ())
+ (:conc-name inotify-))
+ "Contains the stream and file descriptor for a inotify instance."
fd
- stream)
+ stream
+ nonblocking)
+
+;;;; initialisation and stuff
+
+(eval-when (:compile-toplevel :load-toplevel :execute)
+ (defun read-new-value (&optional (stream *query-io*))
+ "READs a value from the STREAM and returns it (wrapped in a list)."
+ (format stream "Enter a new value: ~%")
+ (list (read *query-io*))))
+
+(eval-when (:compile-toplevel :load-toplevel :execute)
+ (defun init-endian ()
+ "Initialises the endianess for the BINARY-TYPES library. Is automatically
+called when the library is loaded."
+ (setf binary-types:*endian*
+ (restart-case #+little-endian :little-endian
+ #+big-endian :big-endian
+ #-(or little-endian big-endian) (error "unknown endianess")
+ (use-value (value)
+ :report "Enter a correct value (either :LITTLE-ENDIAN or :BIG-ENDIAN)."
+ :interactive read-new-value
+ ;; TODO: better way to test for correct value/retry values?
+ (case value
+ ((:little-endian :big-endian) value)
+ (T (error "wrong value supplied (not :LITTLE-ENDIAN or :BIG-ENDIAN)"))))))))
-(defun init-endian ()
- (setf binary-types:*endian*
- #+little-endian :little-endian
- #+big-endian :big-endian
- #-(or little-endian big-endian) (error "unknown endianess")))
+;; initialise the endianess
+(eval-when (:compile-toplevel :load-toplevel :execute)
+ (init-endian))
-(init-endian)
+;;;; basic wrapping of the API
-(defun inotify-read-raw-event (stream)
+(defun read-raw-event-from-stream (stream)
+ "Reads a raw event from the inotify stream."
(let* ((event (binary-types:read-binary 'inotify-event stream))
(len (binary-types:read-binary 'binary-types:u32 stream)))
- (when (> len 0)
+ (when (plusp len)
(with-slots (name) event
- (setf name
- (binary-types:read-binary-string stream :size len :terminators '(0)))))
+ (let ((buffer (make-array len :element-type '(unsigned-byte 8))))
+ (read-sequence buffer stream :end len)
+ (setf name (trivial-utf-8:utf-8-bytes-to-string buffer :end (position 0 buffer))))))
event))
-(defun inotify-read-event (stream)
- (let ((event (inotify-read-raw-event stream)))
+(defun read-event-from-stream (stream)
+ "Reads a event from the inotify stream and converts bitmasks on reading."
+ (let ((event (read-raw-event-from-stream stream)))
(with-slots (mask) event
- (setf mask (foreign-bitfield-symbols 'inotify-flags mask)))
+ (setf mask (foreign-bitfield-symbols 'inotify-flag mask)))
event))
-(defun make-notify ()
- (let* ((fd (inotify-init)))
- (when (< fd 0)
- (error "inotify_init failed: ~A" fd))
- ;; file descriptor is collected with auto-close
- (make-inotify-instance
- fd
- (sb-sys:make-fd-stream fd
- :input T
- :element-type '(unsigned-byte 8)
- :name (format NIL "inotify event queue ~A" fd)
- :auto-close T))))
-
-(defun close-notify (notify)
- (close (inotify-instance-stream notify))
+(defun set-nonblocking (fd nonblocking)
+ "Enables or disables NONBLOCKING mode on a file descriptor FD."
+ (let ((flags (sb-posix:fcntl fd sb-posix:f-getfl)))
+ ;; an error is raised if this fails, so we don't have to do it ourselves
+ (sb-posix:fcntl fd sb-posix:f-setfl
+ (funcall (if nonblocking #'logior #'logxor)
+ flags sb-posix:o-nonblock)))
(values))
-(defun watch (notify pathname flags)
- (let ((path (princ-to-string pathname))
- result)
- (setf result
- (inotify-add-watch (inotify-instance-fd notify)
- path
- (if (listp flags)
- (foreign-bitfield-value 'inotify-flags flags)
- flags)))
- (when (< result 0)
- (error "inotify_add_watch failed: ~A" result))
+(defun init-unregistered-inotify (inotify &optional (nonblocking T))
+ "Creates a new inotify event queue. If NONBLOCKING is set (default),
+the file descriptor is set to non-blocking I/O."
+ (let ((result (c-inotify-init)))
+ (when (minusp result)
+ (perror "inotify_init failed"))
+ (with-slots (fd stream (non-block nonblocking)) inotify
+ (unwind-protect
+ ;; file descriptor is collected with auto-close
+ (progn
+ (setf fd result)
+ (when nonblocking
+ (set-nonblocking fd T)
+ (setf non-block nonblocking))
+ (setf stream
+ (sb-sys:make-fd-stream
+ fd
+ :input T
+ :element-type '(unsigned-byte 8)
+ :name (format NIL "inotify event queue ~A" fd)
+ :auto-close T
+ :buffering (if nonblocking :none :full))))
+ ;; if stream is constructed, gc'ing it will cleanup the file descriptor
+ (unless stream
+ (sb-posix:close fd)))))
+ inotify)
+
+(defun make-unregistered-inotify ()
+ "Creates a new unregistered INOTIFY instance."
+ (init-unregistered-inotify (make-inotify-instance)))
+
+(defun close-inotify (inotify)
+ "Closes the inotify event queue."
+ (close (inotify-stream inotify))
+ (values))
+
+(defun perror (prefix-string)
+ #+sbcl (sb-int:simple-perror prefix-string)
+ #-(or sbcl) (error prefix-string))
+
+(defun ensure-list (arg)
+ (if (listp arg) arg `(,arg)))
+
+(defun translate-keyword-flags (flags)
+ (typecase flags
+ ((or keyword list)
+ (foreign-bitfield-value 'inotify-flag (ensure-list flags)))
+ (T flags)))
+
+(defun watch-raw (inotify pathname flags)
+ "Adds PATHNAME (either of type PATHNAME or STRING) to be watched. FLAGS
+determines how exactly (see inotify(7) for detailed information) and can
+be of type LIST, KEYWORD or a raw numerical value (which isn't checked
+for validity though). Returns a handle which can be used with UNWATCH-RAW."
+ (let* ((path (etypecase pathname
+ (string pathname)
+ (pathname (namestring pathname))))
+ (result (c-inotify-add-watch (inotify-fd inotify)
+ path (translate-keyword-flags flags))))
+ (when (minusp result)
+ (perror "inotify_add_watch failed"))
+ result))
+
+(defun unwatch-raw (inotify handle)
+ "Stops watching the path associated with a HANDLE established by WATCH-RAW."
+ (let ((result (c-inotify-rm-watch (inotify-fd inotify) handle)))
+ (when (minusp result)
+ (perror "inotify_rm_watch failed")))
+ (values))
+
+;;;; support functions, making life easier
+
+(defstruct (registered-inotify-instance
+ (:include inotify-instance)
+ (:constructor make-registered-inotify-instance ())
+ (:conc-name inotify-))
+ "Additionally to the information in INOTIFY-INSTANCE, records watched
+paths in a dictionary."
+ watched)
+
+(defun make-inotify (&optional (nonblocking T))
+ "Creates a new registered INOTIFY instance. In NONBLOCKING mode, the file
+descriptor is set to non-blocking mode. The resulting object has to be
+closed with CLOSE-INOTIFY."
+ (let ((result (make-registered-inotify-instance)))
+ (init-unregistered-inotify result nonblocking)
+ (with-slots (watched) result
+ (setf watched (make-hash-table :test 'equal)))
result))
-(defun unwatch (notify handle)
- (let ((result (inotify-rm-watch (inotify-instance-fd notify) handle)))
- (when (< result 0)
- (error "inotify_rm_watch failed: ~A" result))
- (values)))
+(defun pathname-handle/flags (inotify pathname)
+ "Returns a CONS cell with the values HANDLE and FLAGS if PATHNAME is
+being watched by INOTIFY, else NIL. The match is exact."
+ (gethash pathname (inotify-watched inotify)))
+
+(defun event-pathname/flags (inotify event &optional (handle (slot-value event 'wd)))
+ "Returns two values PATHNAME and FLAGS for an EVENT which were used during
+registration. If HANDLE is specified EVENT is ignored."
+ (block NIL
+ (maphash (lambda (pathname entry)
+ (when (eql (car entry) handle)
+ (return (values pathname (cdr entry)))))
+ (inotify-watched inotify))))
+
+(defun sane-user-flags (inotify pathname flags &key (replace-p T))
+ (check-type flags watch-flag-list)
+ ;; now, :mask-add can't be member of flags
+ ;; merge the flags
+ (let* ((flags (ensure-list flags))
+ (rep-flags (if replace-p
+ (cons :mask-add flags)
+ flags)))
+ (let ((it (gethash pathname (slot-value inotify 'watched))))
+ (if it
+ (union (cdr it) rep-flags :test #'eq)
+ rep-flags))))
+
+(defun watch (inotify pathname flags &key (replace-p T))
+ "Adds PATHNAME (either pathname or string) to be watched and records the
+watched paths. FLAGS (a list of keywords) determines how exactly (see
+inotify(7) for detailed information). Returns a handle which can be used
+with UNWATCH and EVENT-PATHNAME/FLAGS. If REPLACE-P is set to T (default),
+the flags mask is replaced rather than OR-ed to the current mask (if it
+exists). The :MASK-ADD flag is therefore removed from the FLAGS argument."
+ (let* ((flags (sane-user-flags inotify pathname flags :replace-p replace-p))
+ (handle (watch-raw inotify pathname flags)))
+ (with-slots (watched) inotify
+ (setf (gethash pathname watched) (cons handle flags)))
+ handle))
+
+(defun unwatch (inotify &key pathname event handle)
+ "Disables watching the path associated with the supplied HANDLE (which
+may be one from a given EVENT) or PATHNAME."
+ (unless (or pathname event handle)
+ (error "either PATHNAME, EVENT or HANDLE have to be specified"))
+ (when event
+ (setf handle (slot-value event 'wd)))
+ (if handle
+ (unwatch-raw inotify handle)
+ (let ((handle (car (pathname-handle/flags inotify pathname))))
+ (unless handle
+ (error "PATHNAME ~S isn't being watched" pathname))
+ ;; remove even if unwatch-raw throws an error (which can happen if :oneshot is specified)
+ (remhash pathname (inotify-watched inotify))
+ (unwatch-raw inotify handle)))
+ (values))
+
+(defun list-watched (inotify)
+ "Returns a LIST of all watched pathnames in no particular order."
+ (loop
+ for pathname being each hash-key in (inotify-watched inotify)
+ collect pathname))
+
+(defun unix-eagain-p (fd-stream)
+ "Returns T on a FD-STREAM if trying to read from the stream raised a
+EAGAIN error."
+ (multiple-value-bind (result error)
+ (sb-unix:unix-read (sb-sys:fd-stream-fd fd-stream) NIL 0)
+ (declare (ignore result))
+ (= error sb-unix:eagain)))
+
+(defun event-available-p (inotify)
+ "Returns T if an event is available on the queue."
+ (if (inotify-nonblocking inotify)
+ (not (unix-eagain-p (inotify-stream inotify)))
+ (listen (inotify-stream inotify))))
+
+(defun read-event (inotify)
+ "Reads an event from the queue. Blocks if no event is available."
+ (read-event-from-stream (inotify-stream inotify)))
+
+(defun next-event (inotify)
+ "Reads an event from the queue. Returns NIL if none is available."
+ (when (event-available-p inotify)
+ (read-event inotify)))
+
+(defmacro do-events ((var inotify &key blocking-p) &body body)
+ "Loops BODY with VAR bound to the next events retrieved from INOTIFY.
+The macro uses NEXT-EVENT, so reading an event won't block and the loop
+terminates if no events are available."
+ (check-type var symbol)
+ (let ((inotify-sym (gensym)))
+ `(loop
+ with ,var and ,inotify-sym = ,inotify
+ ,.(unless blocking-p
+ `(while (event-available-p ,inotify-sym)))
+ do (progn
+ (setf ,var (read-event ,inotify-sym))
+ ,.body))))
+
+(defun next-events (inotify)
+ "Reads all available events from the queue. Returns a LIST of events."
+ (loop
+ while (event-available-p inotify)
+ collect (read-event inotify)))
projects / cl-inotify.git / blobdiff