1 ;;;; -*- Mode: Lisp; indent-tabs-mode: nil -*-
3 ;;; file-monitor.lisp --- Monitor files on disk.
6 (in-package :iolib
/sockets
)
8 (defclass file-monitor
()
9 ((file :initform
(error "Must supply a file name")
10 :initarg
:file
:accessor file-of
)
11 (timestamp :initarg
:timestamp
:accessor timestamp-of
)
12 (update-fn :initarg
:update-fn
:accessor update-fn-of
)
13 (lock :initarg
:lock
:accessor lock-of
))
14 (:default-initargs
:timestamp
0))
16 (defmethod initialize-instance :after
((monitor file-monitor
) &key file
)
17 (unless (slot-boundp monitor
'lock
)
18 (setf (lock-of monitor
)
19 (bt:make-lock
(format nil
"Lock for monitor of ~S" file
)))))
21 (defmethod print-object ((monitor file-monitor
) stream
)
22 (print-unreadable-object (monitor stream
:type nil
:identity nil
)
23 (format stream
"File monitor for ~S" (file-of monitor
))))
25 (defun monitor-oldp (monitor)
26 (declare (type file-monitor monitor
))
27 (let ((mtime (file-write-date (file-of monitor
))))
28 (values (< (timestamp-of monitor
) mtime
)
31 (defgeneric update-monitor
(monitor)
32 (:method
((monitor file-monitor
))
33 (bt:with-lock-held
((lock-of monitor
))
34 (multiple-value-bind (oldp mtime
) (monitor-oldp monitor
)
36 (funcall (update-fn-of monitor
) (file-of monitor
))
38 (values (timestamp-of monitor
) mtime
)
39 (setf (timestamp-of monitor
) mtime
)))))))