2 Unix SMB/CIFS implementation.
4 Copyright (C) Andrew Tridgell 2006
6 This program 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.
11 This program 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.
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>.
21 notify implementation using inotify
25 #include "../librpc/gen_ndr/notify.h"
29 #if HAVE_SYS_INOTIFY_H
30 #include <sys/inotify.h>
33 #ifdef HAVE_ASM_TYPES_H
34 #include <asm/types.h>
37 #ifndef HAVE_INOTIFY_INIT
39 #include <linux/inotify.h>
40 #include <asm/unistd.h>
44 glibc doesn't define these functions yet (as of March 2006)
46 static int inotify_init(void)
48 return syscall(__NR_inotify_init);
51 static int inotify_add_watch(int fd, const char *path, __u32 mask)
53 return syscall(__NR_inotify_add_watch, fd, path, mask);
56 static int inotify_rm_watch(int fd, int wd)
58 return syscall(__NR_inotify_rm_watch, fd, wd);
62 #include <sys/inotify.h>
67 /* older glibc headers don't have these defines either */
69 #define IN_ONLYDIR 0x01000000
72 #define IN_MASK_ADD 0x20000000
75 struct inotify_private {
76 struct sys_notify_context *ctx;
78 struct inotify_watch_context *watches;
81 struct inotify_watch_context {
82 struct inotify_watch_context *next, *prev;
83 struct inotify_private *in;
85 void (*callback)(struct sys_notify_context *ctx,
87 struct notify_event *ev);
89 uint32_t mask; /* the inotify mask */
90 uint32_t filter; /* the windows completion filter */
96 destroy the inotify private context
98 static int inotify_destructor(struct inotify_private *in)
106 see if a particular event from inotify really does match a requested
109 static bool filter_match(struct inotify_watch_context *w,
110 struct inotify_event *e)
112 DEBUG(10, ("filter_match: e->mask=%x, w->mask=%x, w->filter=%x\n",
113 e->mask, w->mask, w->filter));
115 if ((e->mask & w->mask) == 0) {
116 /* this happens because inotify_add_watch() coalesces watches on the same
117 path, oring their masks together */
121 /* SMB separates the filters for files and directories */
122 if (e->mask & IN_ISDIR) {
123 if ((w->filter & FILE_NOTIFY_CHANGE_DIR_NAME) == 0) {
127 if ((e->mask & IN_ATTRIB) &&
128 (w->filter & (FILE_NOTIFY_CHANGE_ATTRIBUTES|
129 FILE_NOTIFY_CHANGE_LAST_WRITE|
130 FILE_NOTIFY_CHANGE_LAST_ACCESS|
131 FILE_NOTIFY_CHANGE_EA|
132 FILE_NOTIFY_CHANGE_SECURITY))) {
135 if ((e->mask & IN_MODIFY) &&
136 (w->filter & FILE_NOTIFY_CHANGE_ATTRIBUTES)) {
139 if ((w->filter & FILE_NOTIFY_CHANGE_FILE_NAME) == 0) {
150 dispatch one inotify event
152 the cookies are used to correctly handle renames
154 static void inotify_dispatch(struct inotify_private *in,
155 struct inotify_event *e,
156 uint32_t prev_cookie,
157 struct inotify_event *e2)
159 struct inotify_watch_context *w, *next;
160 struct notify_event ne;
162 DEBUG(10, ("inotify_dispatch called with mask=%x, name=[%s]\n",
163 e->mask, e->len ? e->name : ""));
165 /* ignore extraneous events, such as unmount and IN_IGNORED events */
166 if ((e->mask & (IN_ATTRIB|IN_MODIFY|IN_CREATE|IN_DELETE|
167 IN_MOVED_FROM|IN_MOVED_TO)) == 0) {
171 /* map the inotify mask to a action. This gets complicated for
173 if (e->mask & IN_CREATE) {
174 ne.action = NOTIFY_ACTION_ADDED;
175 } else if (e->mask & IN_DELETE) {
176 ne.action = NOTIFY_ACTION_REMOVED;
177 } else if (e->mask & IN_MOVED_FROM) {
178 if (e2 != NULL && e2->cookie == e->cookie) {
179 ne.action = NOTIFY_ACTION_OLD_NAME;
181 ne.action = NOTIFY_ACTION_REMOVED;
183 } else if (e->mask & IN_MOVED_TO) {
184 if (e->cookie == prev_cookie) {
185 ne.action = NOTIFY_ACTION_NEW_NAME;
187 ne.action = NOTIFY_ACTION_ADDED;
190 ne.action = NOTIFY_ACTION_MODIFIED;
194 DEBUG(10, ("inotify_dispatch: ne.action = %d, ne.path = %s\n",
195 ne.action, ne.path));
197 /* find any watches that have this watch descriptor */
198 for (w=in->watches;w;w=next) {
200 if (w->wd == e->wd && filter_match(w, e)) {
201 w->callback(in->ctx, w->private_data, &ne);
205 /* SMB expects a file rename to generate three events, two for
206 the rename and the other for a modify of the
207 destination. Strange! */
208 if (ne.action != NOTIFY_ACTION_NEW_NAME ||
209 (e->mask & IN_ISDIR) != 0) {
213 ne.action = NOTIFY_ACTION_MODIFIED;
216 for (w=in->watches;w;w=next) {
218 if (w->wd == e->wd && filter_match(w, e) &&
219 !(w->filter & FILE_NOTIFY_CHANGE_CREATION)) {
220 w->callback(in->ctx, w->private_data, &ne);
226 called when the kernel has some events for us
228 static void inotify_handler(struct event_context *ev, struct fd_event *fde,
229 uint16_t flags, void *private_data)
231 struct inotify_private *in = talloc_get_type(private_data,
232 struct inotify_private);
234 struct inotify_event *e0, *e;
235 uint32_t prev_cookie=0;
239 we must use FIONREAD as we cannot predict the length of the
240 filenames, and thus can't know how much to allocate
243 if (ioctl(in->fd, FIONREAD, &bufsize) != 0 ||
245 DEBUG(0,("No data on inotify fd?!\n"));
250 e0 = e = (struct inotify_event *)TALLOC_SIZE(in, bufsize + 1);
251 if (e == NULL) return;
252 ((uint8_t *)e)[bufsize] = '\0';
254 status = read_data(in->fd, (char *)e0, bufsize);
255 if (!NT_STATUS_IS_OK(status)) {
256 DEBUG(0,("Failed to read all inotify data - %s\n",
259 /* the inotify fd will now be out of sync,
260 * can't keep reading data off it */
265 /* we can get more than one event in the buffer */
266 while (e && (bufsize >= sizeof(*e))) {
267 struct inotify_event *e2 = NULL;
268 bufsize -= e->len + sizeof(*e);
269 if (bufsize >= sizeof(*e)) {
270 e2 = (struct inotify_event *)(e->len + sizeof(*e) + (char *)e);
272 inotify_dispatch(in, e, prev_cookie, e2);
273 prev_cookie = e->cookie;
281 setup the inotify handle - called the first time a watch is added on
284 static NTSTATUS inotify_setup(struct sys_notify_context *ctx)
286 struct inotify_private *in;
288 if (!lp_parm_bool(-1, "notify", "inotify", True)) {
289 return NT_STATUS_INVALID_SYSTEM_SERVICE;
292 in = talloc(ctx, struct inotify_private);
293 NT_STATUS_HAVE_NO_MEMORY(in);
294 in->fd = inotify_init();
296 DEBUG(0,("Failed to init inotify - %s\n", strerror(errno)));
298 return map_nt_error_from_unix(errno);
303 ctx->private_data = in;
304 talloc_set_destructor(in, inotify_destructor);
306 /* add a event waiting for the inotify fd to be readable */
307 event_add_fd(ctx->ev, in, in->fd, EVENT_FD_READ, inotify_handler, in);
314 map from a change notify mask to a inotify mask. Remove any bits
317 static const struct {
318 uint32_t notify_mask;
319 uint32_t inotify_mask;
320 } inotify_mapping[] = {
321 {FILE_NOTIFY_CHANGE_FILE_NAME, IN_CREATE|IN_DELETE|IN_MOVED_FROM|IN_MOVED_TO},
322 {FILE_NOTIFY_CHANGE_DIR_NAME, IN_CREATE|IN_DELETE|IN_MOVED_FROM|IN_MOVED_TO},
323 {FILE_NOTIFY_CHANGE_ATTRIBUTES, IN_ATTRIB|IN_MOVED_TO|IN_MOVED_FROM|IN_MODIFY},
324 {FILE_NOTIFY_CHANGE_LAST_WRITE, IN_ATTRIB},
325 {FILE_NOTIFY_CHANGE_LAST_ACCESS, IN_ATTRIB},
326 {FILE_NOTIFY_CHANGE_EA, IN_ATTRIB},
327 {FILE_NOTIFY_CHANGE_SECURITY, IN_ATTRIB}
330 static uint32_t inotify_map(struct notify_entry *e)
334 for (i=0;i<ARRAY_SIZE(inotify_mapping);i++) {
335 if (inotify_mapping[i].notify_mask & e->filter) {
336 out |= inotify_mapping[i].inotify_mask;
337 e->filter &= ~inotify_mapping[i].notify_mask;
346 static int watch_destructor(struct inotify_watch_context *w)
348 struct inotify_private *in = w->in;
350 DLIST_REMOVE(w->in->watches, w);
352 /* only rm the watch if its the last one with this wd */
353 for (w=in->watches;w;w=w->next) {
354 if (w->wd == wd) break;
357 DEBUG(10, ("Deleting inotify watch %d\n", wd));
358 if (inotify_rm_watch(in->fd, wd) == -1) {
359 DEBUG(1, ("inotify_rm_watch returned %s\n",
369 add a watch. The watch is removed when the caller calls
370 talloc_free() on *handle
372 NTSTATUS inotify_watch(struct sys_notify_context *ctx,
373 struct notify_entry *e,
374 void (*callback)(struct sys_notify_context *ctx,
376 struct notify_event *ev),
380 struct inotify_private *in;
383 struct inotify_watch_context *w;
384 uint32_t filter = e->filter;
385 void **handle = (void **)handle_p;
387 /* maybe setup the inotify fd */
388 if (ctx->private_data == NULL) {
390 status = inotify_setup(ctx);
391 NT_STATUS_NOT_OK_RETURN(status);
394 in = talloc_get_type(ctx->private_data, struct inotify_private);
396 mask = inotify_map(e);
398 /* this filter can't be handled by inotify */
399 return NT_STATUS_INVALID_PARAMETER;
402 /* using IN_MASK_ADD allows us to cope with inotify() returning the same
403 watch descriptor for muliple watches on the same path */
404 mask |= (IN_MASK_ADD | IN_ONLYDIR);
406 /* get a new watch descriptor for this path */
407 wd = inotify_add_watch(in->fd, e->path, mask);
410 DEBUG(1, ("inotify_add_watch returned %s\n", strerror(errno)));
411 return map_nt_error_from_unix(errno);
414 DEBUG(10, ("inotify_add_watch for %s mask %x returned wd %d\n",
417 w = talloc(in, struct inotify_watch_context);
419 inotify_rm_watch(in->fd, wd);
421 return NT_STATUS_NO_MEMORY;
426 w->callback = callback;
427 w->private_data = private_data;
430 w->path = talloc_strdup(w, e->path);
431 if (w->path == NULL) {
432 inotify_rm_watch(in->fd, wd);
434 return NT_STATUS_NO_MEMORY;
439 DLIST_ADD(in->watches, w);
441 /* the caller frees the handle to stop watching */
442 talloc_set_destructor(w, watch_destructor);