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6f011d81 EZ |
1 | /* Filesystem notifications support for GNU Emacs on the Microsoft Windows API. |
2 | Copyright (C) 2012 Free Software Foundation, Inc. | |
3 | ||
4 | This file is part of GNU Emacs. | |
5 | ||
6 | GNU Emacs is free software: you can redistribute it and/or modify | |
7 | it under the terms of the GNU General Public License as published by | |
8 | the Free Software Foundation, either version 3 of the License, or | |
9 | (at your option) any later version. | |
10 | ||
11 | GNU Emacs is distributed in the hope that it will be useful, | |
12 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
14 | GNU General Public License for more details. | |
15 | ||
16 | You should have received a copy of the GNU General Public License | |
17 | along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>. */ | |
18 | ||
c5c91b84 EZ |
19 | /* Design overview: |
20 | ||
21 | For each watch request, we launch a separate worker thread. The | |
22 | worker thread runs the watch_worker function, which issues an | |
23 | asynchronous call to ReadDirectoryChangesW, and then waits for that | |
24 | call to complete in SleepEx. Waiting in SleepEx puts the thread in | |
25 | an alertable state, so it wakes up when either (a) the call to | |
26 | ReadDirectoryChangesW completes, or (b) the main thread instructs | |
27 | the worker thread to terminate by sending it an APC, see below. | |
28 | ||
29 | When the ReadDirectoryChangesW call completes, its completion | |
30 | routine watch_completion is automatically called. watch_completion | |
31 | stashes the received file events in a buffer used to communicate | |
32 | them to the main thread (using a critical section, so that several | |
33 | threads could use the same buffer), posts a special message, | |
34 | WM_EMACS_FILENOTIFY, to the Emacs's message queue, and returns. | |
35 | That causes the SleepEx function call inside watch_worker to | |
36 | return, and watch_worker then issues another call to | |
37 | ReadDirectoryChangesW. (Except when it does not, see below.) | |
38 | ||
977c6479 EZ |
39 | In a GUI session, The WM_EMACS_FILENOTIFY message, posted to the |
40 | message queue gets dispatched to the main Emacs window procedure, | |
41 | which queues it for processing by w32_read_socket. When | |
42 | w32_read_socket sees this message, it accesses the buffer with file | |
43 | notifications (using a critical section), extracts the information, | |
44 | converts it to a series of FILE_NOTIFY_EVENT events, and stuffs | |
45 | them into the input event queue to be processed by keyboard.c input | |
46 | machinery (read_char via a call to kbd_buffer_get_event). | |
47 | ||
48 | In a non-GUI session, we send the WM_EMACS_FILENOTIFY message to | |
49 | the main (a.k.a. "Lisp") thread instead, since there are no window | |
50 | procedures in console programs. That message wakes up | |
51 | MsgWaitForMultipleObjects inside sys_select, which then signals to | |
52 | its caller that some keyboard input is available. This causes | |
53 | w32_console_read_socket to be called, which accesses the buffer | |
54 | with file notifications and stuffs them into the input event queue | |
55 | for keyboard.c to process. | |
56 | ||
57 | When the FILE_NOTIFY_EVENT event is processed by keyboard.c's | |
58 | kbd_buffer_get_event, it is converted to a Lispy event that can be | |
59 | bound to a command. The default binding is w32notify-handle-event, | |
60 | defined on subr.el. | |
61 | ||
62 | After w32_read_socket or w32_console_read_socket is done processing | |
63 | the notifications, it resets a flag signaling to all watch worker | |
64 | threads that the notifications buffer is available for more input. | |
c5c91b84 EZ |
65 | |
66 | When the watch is removed by a call to w32notify-rm-watch, the main | |
67 | thread requests that the worker thread terminates by queuing an APC | |
68 | for the worker thread. The APC specifies the watch_end function to | |
69 | be called. watch_end calls CancelIo on the outstanding | |
70 | ReadDirectoryChangesW call and closes the handle on which the | |
71 | watched directory was open. When watch_end returns, the | |
72 | watch_completion function is called one last time with the | |
73 | ERROR_OPERATION_ABORTED status, which causes it to clean up and set | |
74 | a flag telling watch_worker to exit without issuing another | |
d6de1760 EZ |
75 | ReadDirectoryChangesW call. The main thread waits for some time |
76 | for the worker thread to exit, and if it doesn't, terminates it | |
77 | forcibly. */ | |
c5c91b84 | 78 | |
6f011d81 EZ |
79 | #include <stddef.h> |
80 | #include <errno.h> | |
81 | ||
82 | /* must include CRT headers *before* config.h */ | |
83 | #include <config.h> | |
84 | ||
85 | #include <windows.h> | |
86 | ||
87 | #include "lisp.h" | |
88 | #include "w32term.h" /* for enter_crit/leave_crit and WM_EMACS_FILENOTIFY */ | |
eb3abb61 | 89 | #include "w32common.h" /* for OS version data */ |
6f011d81 EZ |
90 | #include "w32.h" /* for w32_strerror */ |
91 | #include "coding.h" | |
92 | #include "keyboard.h" | |
93 | #include "frame.h" /* needed by termhooks.h */ | |
94 | #include "termhooks.h" /* for FILE_NOTIFY_EVENT */ | |
95 | ||
96 | struct notification { | |
97 | BYTE *buf; /* buffer for ReadDirectoryChangesW */ | |
98 | OVERLAPPED *io_info; /* the OVERLAPPED structure for async I/O */ | |
99 | BOOL subtree; /* whether to watch subdirectories */ | |
100 | DWORD filter; /* bit mask for events to watch */ | |
101 | char *watchee; /* the file we are interested in */ | |
102 | HANDLE dir; /* handle to the watched directory */ | |
103 | HANDLE thr; /* handle to the thread that watches */ | |
104 | int terminate; /* if non-zero, request for the thread to terminate */ | |
105 | }; | |
106 | ||
107 | /* FIXME: this needs to be changed to support more that one request at | |
108 | a time. */ | |
109 | static struct notification dirwatch; | |
110 | ||
111 | /* Used for communicating notifications to the main thread. */ | |
112 | int notification_buffer_in_use; | |
113 | BYTE file_notifications[16384]; | |
114 | DWORD notifications_size; | |
115 | HANDLE notifications_desc; | |
116 | ||
117 | static Lisp_Object Qfile_name, Qdirectory_name, Qattributes, Qsize; | |
118 | static Lisp_Object Qlast_write_time, Qlast_access_time, Qcreation_time; | |
119 | static Lisp_Object Qsecurity_desc, Qsubtree, watch_list; | |
120 | ||
6f011d81 EZ |
121 | /* Signal to the main thread that we have file notifications for it to |
122 | process. */ | |
123 | static void | |
124 | send_notifications (BYTE *info, DWORD info_size, HANDLE hdir, int *terminate) | |
125 | { | |
126 | int done = 0; | |
127 | FRAME_PTR f = SELECTED_FRAME (); | |
128 | ||
6f011d81 EZ |
129 | |
130 | /* A single buffer is used to communicate all notifications to the | |
131 | main thread. Since both the main thread and several watcher | |
132 | threads could be active at the same time, we use a critical area | |
133 | and an "in-use" flag to synchronize them. A watcher thread can | |
134 | only put its notifications in the buffer if it acquires the | |
135 | critical area and finds the "in-use" flag reset. The main thread | |
136 | resets the flag after it is done processing notifications. | |
137 | ||
138 | FIXME: is there a better way of dealing with this? */ | |
139 | while (!done && !*terminate) | |
140 | { | |
141 | enter_crit (); | |
142 | if (!notification_buffer_in_use) | |
143 | { | |
144 | if (info_size) | |
145 | memcpy (file_notifications, info, info_size); | |
146 | notifications_size = info_size; | |
147 | notifications_desc = hdir; | |
977c6479 EZ |
148 | /* If PostMessage fails, the message queue is full. If that |
149 | happens, the last thing they will worry about is file | |
150 | notifications. So we effectively discard the | |
151 | notification in that case. */ | |
152 | if ((FRAME_TERMCAP_P (f) | |
153 | /* We send the message to the main (a.k.a. "Lisp") | |
154 | thread, where it will wake up MsgWaitForMultipleObjects | |
155 | inside sys_select, causing it to report that there's | |
156 | some keyboard input available. This will in turn cause | |
157 | w32_console_read_socket to be called, which will pick | |
158 | up the file notifications. */ | |
159 | && PostThreadMessage (dwMainThreadId, WM_EMACS_FILENOTIFY, 0, 0)) | |
182b170f | 160 | || (FRAME_W32_P (f) |
182b170f EZ |
161 | && PostMessage (FRAME_W32_WINDOW (f), |
162 | WM_EMACS_FILENOTIFY, 0, 0))) | |
6f011d81 EZ |
163 | notification_buffer_in_use = 1; |
164 | done = 1; | |
6f011d81 EZ |
165 | } |
166 | leave_crit (); | |
167 | if (!done) | |
168 | Sleep (5); | |
169 | } | |
170 | } | |
171 | ||
172 | /* An APC routine to cancel outstanding directory watch. Invoked by | |
173 | the main thread via QueueUserAPC. This is needed because only the | |
174 | thread that issued the ReadDirectoryChangesW call can call CancelIo | |
175 | to cancel that. (CancelIoEx is only available since Vista, so we | |
176 | cannot use it on XP.) */ | |
177 | VOID CALLBACK | |
178 | watch_end (ULONG_PTR arg) | |
179 | { | |
180 | HANDLE hdir = (HANDLE)arg; | |
181 | ||
182 | if (hdir && hdir != INVALID_HANDLE_VALUE) | |
183 | { | |
184 | CancelIo (hdir); | |
185 | CloseHandle (hdir); | |
186 | } | |
187 | } | |
188 | ||
189 | /* A completion routine (a.k.a. APC function) for handling events read | |
190 | by ReadDirectoryChangesW. Called by the OS when the thread which | |
191 | issued the asynchronous ReadDirectoryChangesW call is in the | |
192 | "alertable state", i.e. waiting inside SleepEx call. */ | |
193 | VOID CALLBACK | |
194 | watch_completion (DWORD status, DWORD bytes_ret, OVERLAPPED *io_info) | |
195 | { | |
196 | struct notification *dirwatch; | |
197 | ||
198 | /* Who knows what happened? Perhaps the OVERLAPPED structure was | |
199 | freed by someone already? In any case, we cannot do anything | |
200 | with this request, so just punt and skip it. FIXME: should we | |
201 | raise the 'terminate' flag in this case? */ | |
202 | if (!io_info) | |
203 | return; | |
204 | ||
205 | /* We have a pointer to our dirwatch structure conveniently stashed | |
206 | away in the hEvent member of the OVERLAPPED struct. According to | |
207 | MSDN documentation of ReadDirectoryChangesW: "The hEvent member | |
208 | of the OVERLAPPED structure is not used by the system, so you can | |
209 | use it yourself." */ | |
210 | dirwatch = (struct notification *)io_info->hEvent; | |
211 | if (status == ERROR_OPERATION_ABORTED) | |
212 | { | |
213 | /* We've been called because the main thread told us to issue | |
214 | CancelIo on the directory we watch, and watch_end did so. | |
215 | The directory handle is already closed. We should clean up | |
216 | and exit, signalling to the thread worker routine not to | |
217 | issue another call to ReadDirectoryChangesW. */ | |
218 | xfree (dirwatch->buf); | |
219 | dirwatch->buf = NULL; | |
220 | xfree (dirwatch->io_info); | |
221 | dirwatch->io_info = NULL; | |
222 | xfree (dirwatch->watchee); | |
223 | dirwatch->watchee = NULL; | |
7d605354 | 224 | dirwatch->dir = NULL; |
6f011d81 EZ |
225 | dirwatch->terminate = 1; |
226 | } | |
227 | else | |
228 | { | |
6f011d81 EZ |
229 | /* Tell the main thread we have notifications for it. */ |
230 | send_notifications (dirwatch->buf, bytes_ret, dirwatch->dir, | |
231 | &dirwatch->terminate); | |
232 | } | |
233 | } | |
234 | ||
235 | /* Worker routine for the watch thread. */ | |
236 | static DWORD WINAPI | |
237 | watch_worker (LPVOID arg) | |
238 | { | |
239 | struct notification *dirwatch = (struct notification *)arg; | |
240 | ||
241 | do { | |
242 | BOOL status; | |
243 | DWORD sleep_result; | |
244 | DWORD bytes_ret = 0; | |
245 | ||
246 | if (dirwatch->dir) | |
247 | { | |
248 | status = ReadDirectoryChangesW (dirwatch->dir, dirwatch->buf, 16384, | |
249 | dirwatch->subtree, dirwatch->filter, | |
250 | &bytes_ret, | |
251 | dirwatch->io_info, watch_completion); | |
252 | if (!status) | |
253 | { | |
c5c91b84 | 254 | DebPrint (("watch_worker, abnormal exit: %lu\n", GetLastError ())); |
6f011d81 EZ |
255 | xfree (dirwatch->buf); |
256 | dirwatch->buf = NULL; | |
257 | xfree (dirwatch->io_info); | |
258 | dirwatch->io_info = NULL; | |
259 | CloseHandle (dirwatch->dir); | |
260 | dirwatch->dir = NULL; | |
261 | xfree (dirwatch->watchee); | |
262 | dirwatch->watchee = NULL; | |
263 | return 1; | |
264 | } | |
265 | } | |
266 | /* Sleep indefinitely until awoken by the I/O completion, which | |
267 | could be either a change notification or a cancellation of the | |
268 | watch. */ | |
269 | sleep_result = SleepEx (INFINITE, TRUE); | |
6f011d81 EZ |
270 | } while (!dirwatch->terminate); |
271 | ||
6f011d81 EZ |
272 | return 0; |
273 | } | |
274 | ||
275 | /* Launch a thread to watch changes to FILE in a directory open on | |
276 | handle HDIR. */ | |
277 | static int | |
278 | start_watching (const char *file, HANDLE hdir, BOOL subdirs, DWORD flags) | |
279 | { | |
280 | dirwatch.buf = xmalloc (16384); | |
281 | dirwatch.io_info = xzalloc (sizeof(OVERLAPPED)); | |
282 | /* Stash a pointer to dirwatch structure for use by the completion | |
283 | routine. According to MSDN documentation of ReadDirectoryChangesW: | |
284 | "The hEvent member of the OVERLAPPED structure is not used by the | |
285 | system, so you can use it yourself." */ | |
286 | dirwatch.io_info->hEvent = &dirwatch; | |
287 | dirwatch.subtree = subdirs; | |
288 | dirwatch.filter = flags; | |
289 | dirwatch.watchee = xstrdup (file); | |
290 | dirwatch.terminate = 0; | |
291 | dirwatch.dir = hdir; | |
292 | ||
293 | /* See w32proc.c where it calls CreateThread for the story behind | |
294 | the 2nd and 5th argument in the call to CreateThread. */ | |
295 | dirwatch.thr = CreateThread (NULL, 64 * 1024, watch_worker, | |
296 | (void *)&dirwatch, 0x00010000, NULL); | |
297 | ||
298 | if (!dirwatch.thr) | |
299 | { | |
300 | dirwatch.terminate = 1; | |
301 | xfree (dirwatch.buf); | |
302 | dirwatch.buf = NULL; | |
303 | xfree (dirwatch.io_info); | |
304 | dirwatch.io_info = NULL; | |
305 | xfree (dirwatch.watchee); | |
306 | dirwatch.watchee = NULL; | |
7d605354 | 307 | dirwatch.dir = NULL; |
6f011d81 EZ |
308 | return -1; |
309 | } | |
310 | return 0; | |
311 | } | |
312 | ||
313 | /* Called from the main thread to start watching FILE in PARENT_DIR, | |
314 | subject to FLAGS. If SUBDIRS is TRUE, watch the subdirectories of | |
315 | PARENT_DIR as well. Value is the handle on which the directory is | |
316 | open. */ | |
317 | static HANDLE * | |
318 | add_watch (const char *parent_dir, const char *file, BOOL subdirs, DWORD flags) | |
319 | { | |
320 | HANDLE hdir; | |
321 | ||
322 | if (!file || !*file) | |
323 | return NULL; | |
324 | ||
325 | hdir = CreateFile (parent_dir, | |
326 | FILE_LIST_DIRECTORY, | |
327 | /* FILE_SHARE_DELETE doesn't preclude other | |
328 | processes from deleting files inside | |
329 | parent_dir. */ | |
330 | FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, | |
331 | NULL, OPEN_EXISTING, | |
332 | FILE_FLAG_BACKUP_SEMANTICS | FILE_FLAG_OVERLAPPED, | |
333 | NULL); | |
334 | if (hdir == INVALID_HANDLE_VALUE) | |
335 | return NULL; | |
336 | ||
337 | if (start_watching (file, hdir, subdirs, flags) == 0) | |
338 | return hdir; | |
339 | ||
340 | CloseHandle (hdir); | |
341 | return NULL; | |
342 | } | |
343 | ||
344 | /* Stop watching a directory specified by its handle HDIR. */ | |
345 | static int | |
346 | remove_watch (HANDLE hdir) | |
347 | { | |
348 | if (hdir == dirwatch.dir) | |
349 | { | |
350 | int i; | |
351 | BOOL status; | |
352 | DWORD exit_code, err; | |
353 | ||
354 | /* Only the thread that issued the outstanding I/O call can call | |
355 | CancelIo on it. (CancelIoEx is available only since Vista.) | |
356 | So we need to queue an APC for the worker thread telling it | |
357 | to terminate. */ | |
358 | if (!QueueUserAPC (watch_end, dirwatch.thr, (ULONG_PTR)dirwatch.dir)) | |
359 | DebPrint (("QueueUserAPC failed (%lu)!\n", GetLastError ())); | |
360 | /* We also set the terminate flag, for when the thread is | |
361 | waiting on the critical section that never gets acquired. | |
362 | FIXME: is there a cleaner method? Using SleepEx there is a | |
363 | no-no, as that will lead to recursive APC invocations and | |
364 | stack overflow. */ | |
365 | dirwatch.terminate = 1; | |
366 | /* Wait for the thread to exit. FIXME: is there a better method | |
367 | that is not overly complex? */ | |
368 | for (i = 0; i < 50; i++) | |
369 | { | |
370 | if (!((status = GetExitCodeThread (dirwatch.thr, &exit_code)) | |
371 | && exit_code == STILL_ACTIVE)) | |
372 | break; | |
373 | Sleep (10); | |
374 | } | |
375 | if ((status == FALSE && (err = GetLastError ()) == ERROR_INVALID_HANDLE) | |
376 | || exit_code == STILL_ACTIVE) | |
377 | { | |
378 | if (!(status == FALSE && err == ERROR_INVALID_HANDLE)) | |
379 | TerminateThread (dirwatch.thr, 0); | |
380 | } | |
381 | ||
382 | /* Clean up. */ | |
383 | if (dirwatch.thr) | |
384 | { | |
385 | CloseHandle (dirwatch.thr); | |
386 | dirwatch.thr = NULL; | |
387 | } | |
388 | return 0; | |
389 | } | |
390 | else if (!dirwatch.dir) | |
391 | { | |
392 | DebPrint (("Directory handle already closed!\n")); | |
393 | return 0; | |
394 | } | |
395 | else | |
396 | { | |
397 | DebPrint (("Unknown directory handle!\n")); | |
398 | return -1; | |
399 | } | |
400 | } | |
401 | ||
402 | static DWORD | |
403 | filter_list_to_flags (Lisp_Object filter_list) | |
404 | { | |
405 | DWORD flags = 0; | |
406 | ||
407 | if (NILP (filter_list)) | |
408 | return flags; | |
409 | ||
410 | if (!NILP (Fmember (Qfile_name, filter_list))) | |
411 | flags |= FILE_NOTIFY_CHANGE_FILE_NAME; | |
412 | if (!NILP (Fmember (Qdirectory_name, filter_list))) | |
413 | flags |= FILE_NOTIFY_CHANGE_DIR_NAME; | |
414 | if (!NILP (Fmember (Qattributes, filter_list))) | |
415 | flags |= FILE_NOTIFY_CHANGE_ATTRIBUTES; | |
416 | if (!NILP (Fmember (Qsize, filter_list))) | |
417 | flags |= FILE_NOTIFY_CHANGE_SIZE; | |
418 | if (!NILP (Fmember (Qlast_write_time, filter_list))) | |
419 | flags |= FILE_NOTIFY_CHANGE_LAST_WRITE; | |
420 | if (!NILP (Fmember (Qlast_access_time, filter_list))) | |
421 | flags |= FILE_NOTIFY_CHANGE_LAST_ACCESS; | |
422 | if (!NILP (Fmember (Qcreation_time, filter_list))) | |
423 | flags |= FILE_NOTIFY_CHANGE_CREATION; | |
424 | if (!NILP (Fmember (Qsecurity_desc, filter_list))) | |
425 | flags |= FILE_NOTIFY_CHANGE_SECURITY; | |
426 | ||
427 | return flags; | |
428 | } | |
429 | ||
430 | DEFUN ("w32notify-add-watch", Fw32notify_add_watch, | |
431 | Sw32notify_add_watch, 3, 3, 0, | |
432 | doc: /* Add a watch for filesystem events pertaining to FILE. | |
433 | ||
434 | This arranges for filesystem events pertaining to FILE to be reported | |
435 | to Emacs. Use `w32notify-rm-watch' to cancel the watch. | |
436 | ||
437 | Value is a descriptor for the added watch, or nil if the file | |
438 | cannot be watched. | |
439 | ||
440 | FILTER is a list of conditions for reporting an event. It can include | |
441 | the following symbols: | |
442 | ||
443 | 'file-name' -- report file creation, deletion, or renaming | |
444 | 'directory-name' -- report directory creation, deletion, or renaming | |
445 | 'attributes' -- report changes in attributes | |
446 | 'size' -- report changes in file-size | |
447 | 'last-write-time' -- report changes in last-write time | |
448 | 'last-access-time' -- report changes in last-access time | |
449 | 'creation-time' -- report changes in creation time | |
450 | 'security-desc' -- report changes in security descriptor | |
451 | ||
452 | If FILE is a directory, and FILTER includes 'subtree', then all the | |
453 | subdirectories will also be watched and changes in them reported. | |
454 | ||
455 | When any event happens that satisfies the conditions specified by | |
456 | FILTER, Emacs will call the CALLBACK function passing it a single | |
457 | argument EVENT, which is of the form | |
458 | ||
459 | (DESCRIPTOR ACTION FILE) | |
460 | ||
461 | DESCRIPTOR is the same object as the one returned by this function. | |
462 | ACTION is the description of the event. It could be any one of the | |
463 | following: | |
464 | ||
465 | 'added' -- FILE was added | |
466 | 'removed' -- FILE was deleted | |
467 | 'modified' -- FILE's contents or its attributes were modified | |
468 | 'renamed-from' -- a file was renamed whose old name was FILE | |
469 | 'renamed-to' -- a file was renamed and its new name is FILE | |
470 | ||
471 | FILE is the name of the file whose event is being reported. */) | |
472 | (Lisp_Object file, Lisp_Object filter, Lisp_Object callback) | |
473 | { | |
474 | Lisp_Object encoded_file, watch_object, watch_descriptor; | |
475 | char parent_dir[MAX_PATH], *basename; | |
476 | size_t fn_len; | |
477 | HANDLE hdir; | |
478 | DWORD flags; | |
479 | BOOL subdirs = FALSE; | |
480 | Lisp_Object lisp_errstr; | |
481 | char *errstr; | |
482 | ||
483 | CHECK_LIST (filter); | |
484 | ||
485 | /* The underlying features are available only since XP. */ | |
486 | if (os_subtype == OS_9X | |
487 | || (w32_major_version == 5 && w32_major_version < 1)) | |
488 | { | |
489 | errno = ENOSYS; | |
490 | report_file_error ("Watching filesystem events is not supported", | |
491 | Qnil); | |
492 | } | |
493 | ||
7d605354 EZ |
494 | if (dirwatch.dir) |
495 | error ("File watch already active"); | |
496 | ||
6f011d81 EZ |
497 | /* We needa full absolute file name of FILE, and we need to remove |
498 | any trailing slashes from it, so that GetFullPathName below gets | |
499 | the basename part correctly. */ | |
500 | file = Fdirectory_file_name (Fexpand_file_name (file, Qnil)); | |
501 | encoded_file = ENCODE_FILE (file); | |
502 | ||
503 | fn_len = GetFullPathName (SDATA (encoded_file), MAX_PATH, parent_dir, | |
504 | &basename); | |
505 | if (!fn_len) | |
506 | { | |
507 | errstr = w32_strerror (0); | |
508 | errno = EINVAL; | |
509 | if (!NILP (Vlocale_coding_system)) | |
510 | lisp_errstr | |
511 | = code_convert_string_norecord (build_unibyte_string (errstr), | |
512 | Vlocale_coding_system, 0); | |
513 | else | |
514 | lisp_errstr = build_string (errstr); | |
515 | report_file_error ("GetFullPathName failed", | |
516 | Fcons (lisp_errstr, Fcons (file, Qnil))); | |
517 | } | |
518 | /* We need the parent directory without the slash that follows it. | |
519 | If BASENAME is NULL, the argument was the root directory on its | |
520 | drive. */ | |
521 | if (basename) | |
522 | basename[-1] = '\0'; | |
523 | else | |
524 | subdirs = TRUE; | |
525 | ||
526 | if (!NILP (Fmember (Qsubtree, filter))) | |
527 | subdirs = TRUE; | |
528 | ||
529 | flags = filter_list_to_flags (filter); | |
530 | ||
531 | hdir = add_watch (parent_dir, basename, subdirs, flags); | |
532 | if (!hdir) | |
533 | { | |
534 | DWORD err = GetLastError (); | |
535 | ||
536 | errno = EINVAL; | |
537 | if (err) | |
538 | { | |
539 | errstr = w32_strerror (err); | |
540 | if (!NILP (Vlocale_coding_system)) | |
541 | lisp_errstr | |
542 | = code_convert_string_norecord (build_unibyte_string (errstr), | |
543 | Vlocale_coding_system, 0); | |
544 | else | |
545 | lisp_errstr = build_string (errstr); | |
546 | report_file_error ("Cannot watch file", | |
547 | Fcons (lisp_errstr, Fcons (file, Qnil))); | |
548 | } | |
549 | else | |
550 | report_file_error ("Cannot watch file", Fcons (file, Qnil)); | |
551 | } | |
552 | /* Store watch object in watch list. */ | |
553 | watch_descriptor = make_number (hdir); | |
554 | watch_object = Fcons (watch_descriptor, callback); | |
555 | watch_list = Fcons (watch_object, watch_list); | |
556 | ||
557 | return watch_descriptor; | |
558 | } | |
559 | ||
560 | DEFUN ("w32notify-rm-watch", Fw32notify_rm_watch, | |
561 | Sw32notify_rm_watch, 1, 1, 0, | |
562 | doc: /* Remove an existing watch specified by its WATCH-DESCRIPTOR. | |
563 | ||
564 | WATCH-DESCRIPTOR should be an object returned by `w32notify-add-watch'. */) | |
565 | (Lisp_Object watch_descriptor) | |
566 | { | |
567 | Lisp_Object watch_object; | |
568 | HANDLE hdir = (HANDLE)XINT (watch_descriptor); | |
569 | ||
570 | if (remove_watch (hdir) == -1) | |
571 | report_file_error ("Could not remove watch", Fcons (watch_descriptor, | |
572 | Qnil)); | |
573 | ||
574 | /* Remove watch descriptor from watch list. */ | |
575 | watch_object = Fassoc (watch_descriptor, watch_list); | |
576 | if (!NILP (watch_object)) | |
577 | watch_list = Fdelete (watch_object, watch_list); | |
578 | ||
579 | return Qnil; | |
580 | } | |
581 | ||
582 | Lisp_Object | |
583 | get_watch_object (Lisp_Object desc) | |
584 | { | |
585 | return Fassoc (desc, watch_list); | |
586 | } | |
587 | ||
588 | void | |
589 | syms_of_w32notify (void) | |
590 | { | |
591 | DEFSYM (Qfile_name, "file-name"); | |
592 | DEFSYM (Qdirectory_name, "directory-name"); | |
593 | DEFSYM (Qattributes, "attributes"); | |
594 | DEFSYM (Qsize, "size"); | |
595 | DEFSYM (Qlast_write_time, "last-write-time"); | |
596 | DEFSYM (Qlast_access_time, "last-access-time"); | |
597 | DEFSYM (Qcreation_time, "creation-time"); | |
598 | DEFSYM (Qsecurity_desc, "security-desc"); | |
599 | DEFSYM (Qsubtree, "subtree"); | |
600 | ||
601 | defsubr (&Sw32notify_add_watch); | |
602 | defsubr (&Sw32notify_rm_watch); | |
603 | ||
604 | staticpro (&watch_list); | |
605 | ||
606 | Fprovide (intern_c_string ("w32notify"), Qnil); | |
607 | } |