1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
|
;;; Lisparuga
;;; Copyright © 2020 David Thompson <dthompson2@worcester.edu>
;;;
;;; Lisparuga is free software: you can redistribute it and/or modify
;;; it under the terms of the GNU General Public License as published
;;; by the Free Software Foundation, either version 3 of the License,
;;; or (at your option) any later version.
;;;
;;; Lisparuga is distributed in the hope that it will be useful, but
;;; WITHOUT ANY WARRANTY; without even the implied warranty of
;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
;;; General Public License for more details.
;;;
;;; You should have received a copy of the GNU General Public License
;;; along with Lisparuga. If not, see <http://www.gnu.org/licenses/>.
;;; Commentary:
;;
;; Inotify bindings.
;;
;;; Code:
(define-module (lisparuga inotify)
#:use-module (ice-9 binary-ports)
#:use-module (ice-9 format)
#:use-module (ice-9 match)
#:use-module (rnrs bytevectors)
#:use-module (srfi srfi-9)
#:use-module (srfi srfi-9 gnu)
#:use-module (system foreign)
#:export (make-inotify
inotify?
inotify-watches
inotify-add-watch!
inotify-pending-events?
inotify-read-event
inotify-watch?
inotify-watch-id
inotify-watch-file-name
inotify-watch-remove!
inotify-event?
inotify-event-watch
inotify-event-type
inotify-event-cookie
inotify-event-file-name))
(define libc (dynamic-link))
(define inotify-init
(pointer->procedure int (dynamic-func "inotify_init" libc) '()))
(define inotify-add-watch
(pointer->procedure int (dynamic-func "inotify_add_watch" libc)
(list int '* uint32)))
(define inotify-rm-watch
(pointer->procedure int (dynamic-func "inotify_rm_watch" libc)
(list int int)))
(define IN_ACCESS #x00000001) ; file was accessed.
(define IN_MODIFY #x00000002) ; file was modified.
(define IN_ATTRIB #x00000004) ; metadata changed
(define IN_CLOSE_WRITE #x00000008) ; file opened for writing closed
(define IN_CLOSE_NOWRITE #x00000010) ; file not opened for writing closed
(define IN_OPEN #x00000020) ; file was opened
(define IN_MOVED_FROM #x00000040) ; file was moved from X
(define IN_MOVED_TO #x00000080) ; file was moved to Y
(define IN_CREATE #x00000100) ; subfile was created
(define IN_DELETE #x00000200) ; subfile was deleted
(define IN_DELETE_SELF #x00000400) ; self was deleted
(define IN_MOVE_SELF #x00000800) ; self was moved
;; Kernel flags
(define IN_UNMOUNT #x00002000) ; backing fs was unmounted
(define IN_Q_OVERFLOW #x00004000) ; event queue overflowed
(define IN_IGNORED #x00008000) ; file was ignored
;; Special flags
(define IN_ONLYDIR #x01000000) ; only watch if directory
(define IN_DONT_FOLLOW #x02000000) ; do not follow symlink
(define IN_EXCL_UNLINK #x04000000) ; exclude events on unlinked objects
(define IN_MASK_ADD #x20000000) ; add to the mask of an existing watch
(define IN_ISDIR #x40000000) ; event occurred against directory
(define IN_ONESHOT #x80000000) ; only send event once
(define mask/symbol (make-hash-table))
(define symbol/mask (make-hash-table))
(for-each (match-lambda
((sym mask)
(hashq-set! symbol/mask sym mask)
(hashv-set! mask/symbol mask sym)))
`((access ,IN_ACCESS)
(modify ,IN_MODIFY)
(attrib ,IN_ATTRIB)
(close-write ,IN_CLOSE_WRITE)
(close-no-write ,IN_CLOSE_NOWRITE)
(open ,IN_OPEN)
(moved-from ,IN_MOVED_FROM)
(moved-to ,IN_MOVED_TO)
(create ,IN_CREATE)
(delete ,IN_DELETE)
(delete-self ,IN_DELETE_SELF)
(move-self ,IN_MOVE_SELF)
(only-dir ,IN_ONLYDIR)
(dont-follow ,IN_DONT_FOLLOW)
(exclude-unlink ,IN_EXCL_UNLINK)
(is-directory ,IN_ISDIR)
(once ,IN_ONESHOT)))
(define (symbol->mask sym)
(hashq-ref symbol/mask sym))
(define (mask->symbol sym)
(hashq-ref mask/symbol sym))
(define-record-type <inotify>
(%make-inotify port buffer buffer-pointer watches)
inotify?
(port inotify-port)
(buffer inotify-buffer)
(buffer-pointer inotify-buffer-pointer)
(watches inotify-watches))
(define-record-type <inotify-watch>
(make-inotify-watch id file-name owner)
inotify-watch?
(id inotify-watch-id)
(file-name inotify-watch-file-name)
(owner inotify-watch-owner))
(define-record-type <inotify-event>
(make-inotify-event watch type cookie file-name)
inotify-event?
(watch inotify-event-watch)
(type inotify-event-type)
(cookie inotify-event-cookie)
(file-name inotify-event-file-name))
(define (display-inotify inotify port)
(format port "#<inotify port: ~a>" (inotify-port inotify)))
(define (display-inotify-watch watch port)
(format port "#<inotify-watch id: ~d file-name: ~a>"
(inotify-watch-id watch)
(inotify-watch-file-name watch)))
(define (display-inotify-event event port)
(format port "#<inotify-event type: ~s cookie: ~d file-name: ~a watch: ~a>"
(inotify-event-type event)
(inotify-event-cookie event)
(inotify-event-file-name event)
(inotify-event-watch event)))
(set-record-type-printer! <inotify> display-inotify)
(set-record-type-printer! <inotify-watch> display-inotify-watch)
(set-record-type-printer! <inotify-event> display-inotify-event)
(define (make-inotify)
(let ((fd (inotify-init))
(buffer (make-bytevector 4096)))
(%make-inotify (fdopen fd "r")
buffer
(bytevector->pointer buffer)
(make-hash-table))))
(define (inotify-fd inotify)
(port->fdes (inotify-port inotify)))
(define (absolute-file-name file-name)
(if (absolute-file-name? file-name)
file-name
(string-append (getcwd) "/" file-name)))
(define (inotify-add-watch! inotify file-name modes)
(let* ((abs-file-name (absolute-file-name file-name))
(wd (inotify-add-watch (inotify-fd inotify)
(string->pointer abs-file-name)
(apply logior (map symbol->mask modes))))
(watch (make-inotify-watch wd abs-file-name inotify)))
(hashv-set! (inotify-watches inotify) wd watch)
watch))
(define (inotify-watch-remove! watch)
(inotify-rm-watch (inotify-fd (inotify-watch-owner watch))
(inotify-watch-id watch))
(hashv-remove! (inotify-watches (inotify-watch-owner watch))
(inotify-watch-id watch)))
(define (inotify-pending-events? inotify)
;; Sometimes an interrupt happens during the char-ready? call and an
;; exception is thrown. Just return #f in that case and move on
;; with life.
(false-if-exception (char-ready? (inotify-port inotify))))
(define (read-int port buffer)
(get-bytevector-n! port buffer 0 (sizeof int))
(bytevector-sint-ref buffer 0 (native-endianness) (sizeof int)))
(define (read-uint32 port buffer)
(get-bytevector-n! port buffer 0 (sizeof uint32))
(bytevector-uint-ref buffer 0 (native-endianness) (sizeof uint32)))
(define (read-string port buffer buffer-pointer length)
(and (> length 0)
(begin
(get-bytevector-n! port buffer 0 length)
(pointer->string buffer-pointer))))
(define (inotify-read-event inotify)
(let* ((port (inotify-port inotify))
(buffer (inotify-buffer inotify))
(wd (read-int port buffer))
(event-mask (read-uint32 port buffer))
(cookie (read-uint32 port buffer))
(len (read-uint32 port buffer))
(name (read-string port buffer (inotify-buffer-pointer inotify) len)))
(make-inotify-event (hashv-ref (inotify-watches inotify) wd)
(mask->symbol event-mask) cookie name)))
|