source: branches/samba-3.5.x/source3/smbd/notify_internal.c

Last change on this file was 414, checked in by Herwig Bauernfeind, 15 years ago

Samba 3.5.0: Initial import
File size: 23.9 KB
Line 
1/*
2 Unix SMB/CIFS implementation.
3
4 Copyright (C) Andrew Tridgell 2006
5
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.
10
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.
15
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/>.
18*/
19
20/*
21 this is the change notify database. It implements mechanisms for
22 storing current change notify waiters in a tdb, and checking if a
23 given event matches any of the stored notify waiiters.
24*/
25
26#include "includes.h"
27#include "librpc/gen_ndr/ndr_notify.h"
28
29struct notify_context {
30 struct db_context *db_recursive;
31 struct db_context *db_onelevel;
32 struct server_id server;
33 struct messaging_context *messaging_ctx;
34 struct notify_list *list;
35 struct notify_array *array;
36 int seqnum;
37 struct sys_notify_context *sys_notify_ctx;
38 TDB_DATA key;
39};
40
41
42struct notify_list {
43 struct notify_list *next, *prev;
44 void *private_data;
45 void (*callback)(void *, const struct notify_event *);
46 void *sys_notify_handle;
47 int depth;
48};
49
50#define NOTIFY_KEY "notify array"
51
52#define NOTIFY_ENABLE "notify:enable"
53#define NOTIFY_ENABLE_DEFAULT True
54
55static NTSTATUS notify_remove_all(struct notify_context *notify,
56 const struct server_id *server);
57static void notify_handler(struct messaging_context *msg_ctx, void *private_data,
58 uint32_t msg_type, struct server_id server_id, DATA_BLOB *data);
59
60/*
61 destroy the notify context
62*/
63static int notify_destructor(struct notify_context *notify)
64{
65 messaging_deregister(notify->messaging_ctx, MSG_PVFS_NOTIFY, notify);
66
67 if (notify->list != NULL) {
68 notify_remove_all(notify, &notify->server);
69 }
70
71 return 0;
72}
73
74/*
75 Open up the notify.tdb database. You should close it down using
76 talloc_free(). We need the messaging_ctx to allow for notifications
77 via internal messages
78*/
79struct notify_context *notify_init(TALLOC_CTX *mem_ctx, struct server_id server,
80 struct messaging_context *messaging_ctx,
81 struct event_context *ev,
82 connection_struct *conn)
83{
84 struct notify_context *notify;
85
86 if (!lp_change_notify(conn->params)) {
87 return NULL;
88 }
89
90 notify = talloc(mem_ctx, struct notify_context);
91 if (notify == NULL) {
92 return NULL;
93 }
94
95 notify->db_recursive = db_open(notify, lock_path("notify.tdb"),
96 0, TDB_SEQNUM|TDB_CLEAR_IF_FIRST,
97 O_RDWR|O_CREAT, 0644);
98 if (notify->db_recursive == NULL) {
99 talloc_free(notify);
100 return NULL;
101 }
102
103 notify->db_onelevel = db_open(notify, lock_path("notify_onelevel.tdb"),
104 0, TDB_SEQNUM|TDB_CLEAR_IF_FIRST,
105 O_RDWR|O_CREAT, 0644);
106 if (notify->db_onelevel == NULL) {
107 talloc_free(notify);
108 return NULL;
109 }
110
111 notify->server = server;
112 notify->messaging_ctx = messaging_ctx;
113 notify->list = NULL;
114 notify->array = NULL;
115 notify->seqnum = notify->db_recursive->get_seqnum(
116 notify->db_recursive);
117 notify->key = string_term_tdb_data(NOTIFY_KEY);
118
119 talloc_set_destructor(notify, notify_destructor);
120
121 /* register with the messaging subsystem for the notify
122 message type */
123 messaging_register(notify->messaging_ctx, notify,
124 MSG_PVFS_NOTIFY, notify_handler);
125
126 notify->sys_notify_ctx = sys_notify_context_create(conn, notify, ev);
127
128 return notify;
129}
130
131/*
132 lock and fetch the record
133*/
134static NTSTATUS notify_fetch_locked(struct notify_context *notify, struct db_record **rec)
135{
136 *rec = notify->db_recursive->fetch_locked(notify->db_recursive,
137 notify, notify->key);
138 if (*rec == NULL) {
139 return NT_STATUS_INTERNAL_DB_CORRUPTION;
140 }
141 return NT_STATUS_OK;
142}
143
144/*
145 load the notify array
146*/
147static NTSTATUS notify_load(struct notify_context *notify, struct db_record *rec)
148{
149 TDB_DATA dbuf;
150 DATA_BLOB blob;
151 NTSTATUS status;
152 int seqnum;
153
154 seqnum = notify->db_recursive->get_seqnum(notify->db_recursive);
155
156 if (seqnum == notify->seqnum && notify->array != NULL) {
157 return NT_STATUS_OK;
158 }
159
160 notify->seqnum = seqnum;
161
162 talloc_free(notify->array);
163 notify->array = TALLOC_ZERO_P(notify, struct notify_array);
164 NT_STATUS_HAVE_NO_MEMORY(notify->array);
165
166 if (!rec) {
167 if (notify->db_recursive->fetch(notify->db_recursive, notify,
168 notify->key, &dbuf) != 0) {
169 return NT_STATUS_INTERNAL_DB_CORRUPTION;
170 }
171 } else {
172 dbuf = rec->value;
173 }
174
175 blob.data = (uint8 *)dbuf.dptr;
176 blob.length = dbuf.dsize;
177
178 status = NT_STATUS_OK;
179 if (blob.length > 0) {
180 enum ndr_err_code ndr_err;
181 ndr_err = ndr_pull_struct_blob(&blob, notify->array, NULL, notify->array,
182 (ndr_pull_flags_fn_t)ndr_pull_notify_array);
183 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
184 status = ndr_map_error2ntstatus(ndr_err);
185 }
186 }
187
188 if (DEBUGLEVEL >= 10) {
189 DEBUG(10, ("notify_load:\n"));
190 NDR_PRINT_DEBUG(notify_array, notify->array);
191 }
192
193 if (!rec) {
194 talloc_free(dbuf.dptr);
195 }
196
197 return status;
198}
199
200/*
201 compare notify entries for sorting
202*/
203static int notify_compare(const void *p1, const void *p2)
204{
205 const struct notify_entry *e1 = (const struct notify_entry *)p1;
206 const struct notify_entry *e2 = (const struct notify_entry *)p2;
207 return strcmp(e1->path, e2->path);
208}
209
210/*
211 save the notify array
212*/
213static NTSTATUS notify_save(struct notify_context *notify, struct db_record *rec)
214{
215 TDB_DATA dbuf;
216 DATA_BLOB blob;
217 NTSTATUS status;
218 enum ndr_err_code ndr_err;
219 TALLOC_CTX *tmp_ctx;
220
221 /* if possible, remove some depth arrays */
222 while (notify->array->num_depths > 0 &&
223 notify->array->depth[notify->array->num_depths-1].num_entries == 0) {
224 notify->array->num_depths--;
225 }
226
227 /* we might just be able to delete the record */
228 if (notify->array->num_depths == 0) {
229 return rec->delete_rec(rec);
230 }
231
232 tmp_ctx = talloc_new(notify);
233 NT_STATUS_HAVE_NO_MEMORY(tmp_ctx);
234
235 ndr_err = ndr_push_struct_blob(&blob, tmp_ctx, NULL, notify->array,
236 (ndr_push_flags_fn_t)ndr_push_notify_array);
237 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
238 talloc_free(tmp_ctx);
239 return ndr_map_error2ntstatus(ndr_err);
240 }
241
242 if (DEBUGLEVEL >= 10) {
243 DEBUG(10, ("notify_save:\n"));
244 NDR_PRINT_DEBUG(notify_array, notify->array);
245 }
246
247 dbuf.dptr = blob.data;
248 dbuf.dsize = blob.length;
249
250 status = rec->store(rec, dbuf, TDB_REPLACE);
251 talloc_free(tmp_ctx);
252
253 return status;
254}
255
256
257/*
258 handle incoming notify messages
259*/
260static void notify_handler(struct messaging_context *msg_ctx, void *private_data,
261 uint32_t msg_type, struct server_id server_id, DATA_BLOB *data)
262{
263 struct notify_context *notify = talloc_get_type(private_data, struct notify_context);
264 enum ndr_err_code ndr_err;
265 struct notify_event ev;
266 TALLOC_CTX *tmp_ctx = talloc_new(notify);
267 struct notify_list *listel;
268
269 if (tmp_ctx == NULL) {
270 return;
271 }
272
273 ndr_err = ndr_pull_struct_blob(data, tmp_ctx, NULL, &ev,
274 (ndr_pull_flags_fn_t)ndr_pull_notify_event);
275 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
276 talloc_free(tmp_ctx);
277 return;
278 }
279
280 for (listel=notify->list;listel;listel=listel->next) {
281 if (listel->private_data == ev.private_data) {
282 listel->callback(listel->private_data, &ev);
283 break;
284 }
285 }
286
287 talloc_free(tmp_ctx);
288}
289
290/*
291 callback from sys_notify telling us about changes from the OS
292*/
293static void sys_notify_callback(struct sys_notify_context *ctx,
294 void *ptr, struct notify_event *ev)
295{
296 struct notify_list *listel = talloc_get_type(ptr, struct notify_list);
297 ev->private_data = listel;
298 DEBUG(10, ("sys_notify_callback called with action=%d, for %s\n",
299 ev->action, ev->path));
300 listel->callback(listel->private_data, ev);
301}
302
303/*
304 add an entry to the notify array
305*/
306static NTSTATUS notify_add_array(struct notify_context *notify, struct db_record *rec,
307 struct notify_entry *e,
308 void *private_data, int depth)
309{
310 int i;
311 struct notify_depth *d;
312 struct notify_entry *ee;
313
314 /* possibly expand the depths array */
315 if (depth >= notify->array->num_depths) {
316 d = talloc_realloc(notify->array, notify->array->depth,
317 struct notify_depth, depth+1);
318 NT_STATUS_HAVE_NO_MEMORY(d);
319 for (i=notify->array->num_depths;i<=depth;i++) {
320 ZERO_STRUCT(d[i]);
321 }
322 notify->array->depth = d;
323 notify->array->num_depths = depth+1;
324 }
325 d = &notify->array->depth[depth];
326
327 /* expand the entries array */
328 ee = talloc_realloc(notify->array->depth, d->entries, struct notify_entry,
329 d->num_entries+1);
330 NT_STATUS_HAVE_NO_MEMORY(ee);
331 d->entries = ee;
332
333 d->entries[d->num_entries] = *e;
334 d->entries[d->num_entries].private_data = private_data;
335 d->entries[d->num_entries].server = notify->server;
336 d->entries[d->num_entries].path_len = strlen(e->path);
337 d->num_entries++;
338
339 d->max_mask |= e->filter;
340 d->max_mask_subdir |= e->subdir_filter;
341
342 if (d->num_entries > 1) {
343 qsort(d->entries, d->num_entries, sizeof(d->entries[0]), notify_compare);
344 }
345
346 /* recalculate the maximum masks */
347 d->max_mask = 0;
348 d->max_mask_subdir = 0;
349
350 for (i=0;i<d->num_entries;i++) {
351 d->max_mask |= d->entries[i].filter;
352 d->max_mask_subdir |= d->entries[i].subdir_filter;
353 }
354
355 return notify_save(notify, rec);
356}
357
358/*
359 Add a non-recursive watch
360*/
361
362static void notify_add_onelevel(struct notify_context *notify,
363 struct notify_entry *e, void *private_data)
364{
365 struct notify_entry_array *array;
366 struct db_record *rec;
367 DATA_BLOB blob;
368 TDB_DATA dbuf;
369 enum ndr_err_code ndr_err;
370 NTSTATUS status;
371
372 array = talloc_zero(talloc_tos(), struct notify_entry_array);
373 if (array == NULL) {
374 return;
375 }
376
377 rec = notify->db_onelevel->fetch_locked(
378 notify->db_onelevel, talloc_tos(),
379 make_tdb_data((uint8_t *)&e->dir_id, sizeof(e->dir_id)));
380 if (rec == NULL) {
381 DEBUG(10, ("notify_add_onelevel: fetch_locked for %s failed"
382 "\n", file_id_string_tos(&e->dir_id)));
383 TALLOC_FREE(array);
384 return;
385 }
386
387 blob.data = (uint8_t *)rec->value.dptr;
388 blob.length = rec->value.dsize;
389
390 if (blob.length > 0) {
391 ndr_err = ndr_pull_struct_blob(
392 &blob, array, NULL, array,
393 (ndr_pull_flags_fn_t)ndr_pull_notify_entry_array);
394 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
395 DEBUG(10, ("ndr_pull_notify_entry_array failed: %s\n",
396 ndr_errstr(ndr_err)));
397 TALLOC_FREE(array);
398 return;
399 }
400 if (DEBUGLEVEL >= 10) {
401 DEBUG(10, ("notify_add_onelevel:\n"));
402 NDR_PRINT_DEBUG(notify_entry_array, array);
403 }
404 }
405
406 array->entries = talloc_realloc(array, array->entries,
407 struct notify_entry,
408 array->num_entries+1);
409 if (array->entries == NULL) {
410 TALLOC_FREE(array);
411 return;
412 }
413 array->entries[array->num_entries] = *e;
414 array->entries[array->num_entries].private_data = private_data;
415 array->entries[array->num_entries].server = notify->server;
416 array->num_entries += 1;
417
418 ndr_err = ndr_push_struct_blob(
419 &blob, rec, NULL, array,
420 (ndr_push_flags_fn_t)ndr_push_notify_entry_array);
421 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
422 DEBUG(10, ("ndr_push_notify_entry_array failed: %s\n",
423 ndr_errstr(ndr_err)));
424 TALLOC_FREE(array);
425 return;
426 }
427
428 if (DEBUGLEVEL >= 10) {
429 DEBUG(10, ("notify_add_onelevel:\n"));
430 NDR_PRINT_DEBUG(notify_entry_array, array);
431 }
432
433 dbuf.dptr = blob.data;
434 dbuf.dsize = blob.length;
435
436 status = rec->store(rec, dbuf, TDB_REPLACE);
437 TALLOC_FREE(array);
438 if (!NT_STATUS_IS_OK(status)) {
439 DEBUG(10, ("notify_add_onelevel: store failed: %s\n",
440 nt_errstr(status)));
441 return;
442 }
443 e->filter = 0;
444 return;
445}
446
447
448/*
449 add a notify watch. This is called when a notify is first setup on a open
450 directory handle.
451*/
452NTSTATUS notify_add(struct notify_context *notify, struct notify_entry *e0,
453 void (*callback)(void *, const struct notify_event *),
454 void *private_data)
455{
456 struct notify_entry e = *e0;
457 NTSTATUS status;
458 char *tmp_path = NULL;
459 struct notify_list *listel;
460 size_t len;
461 int depth;
462 struct db_record *rec;
463
464 /* see if change notify is enabled at all */
465 if (notify == NULL) {
466 return NT_STATUS_NOT_IMPLEMENTED;
467 }
468
469 status = notify_fetch_locked(notify, &rec);
470 NT_STATUS_NOT_OK_RETURN(status);
471
472 status = notify_load(notify, rec);
473 if (!NT_STATUS_IS_OK(status)) {
474 talloc_free(rec);
475 return status;
476 }
477
478 /* cope with /. on the end of the path */
479 len = strlen(e.path);
480 if (len > 1 && e.path[len-1] == '.' && e.path[len-2] == '/') {
481 tmp_path = talloc_strndup(notify, e.path, len-2);
482 if (tmp_path == NULL) {
483 status = NT_STATUS_NO_MEMORY;
484 goto done;
485 }
486 e.path = tmp_path;
487 }
488
489 depth = count_chars(e.path, '/');
490
491 listel = TALLOC_ZERO_P(notify, struct notify_list);
492 if (listel == NULL) {
493 status = NT_STATUS_NO_MEMORY;
494 goto done;
495 }
496
497 listel->private_data = private_data;
498 listel->callback = callback;
499 listel->depth = depth;
500 DLIST_ADD(notify->list, listel);
501
502 /* ignore failures from sys_notify */
503 if (notify->sys_notify_ctx != NULL) {
504 /*
505 this call will modify e.filter and e.subdir_filter
506 to remove bits handled by the backend
507 */
508 status = sys_notify_watch(notify->sys_notify_ctx, &e,
509 sys_notify_callback, listel,
510 &listel->sys_notify_handle);
511 if (NT_STATUS_IS_OK(status)) {
512 talloc_steal(listel, listel->sys_notify_handle);
513 }
514 }
515
516 if (e.filter != 0) {
517 notify_add_onelevel(notify, &e, private_data);
518 status = NT_STATUS_OK;
519 }
520
521 /* if the system notify handler couldn't handle some of the
522 filter bits, or couldn't handle a request for recursion
523 then we need to install it in the array used for the
524 intra-samba notify handling */
525 if (e.filter != 0 || e.subdir_filter != 0) {
526 status = notify_add_array(notify, rec, &e, private_data, depth);
527 }
528
529done:
530 talloc_free(rec);
531 talloc_free(tmp_path);
532
533 return status;
534}
535
536NTSTATUS notify_remove_onelevel(struct notify_context *notify,
537 const struct file_id *fid,
538 void *private_data)
539{
540 struct notify_entry_array *array;
541 struct db_record *rec;
542 DATA_BLOB blob;
543 TDB_DATA dbuf;
544 enum ndr_err_code ndr_err;
545 NTSTATUS status;
546 int i;
547
548 if (notify == NULL) {
549 return NT_STATUS_NOT_IMPLEMENTED;
550 }
551
552 array = talloc_zero(talloc_tos(), struct notify_entry_array);
553 if (array == NULL) {
554 return NT_STATUS_NO_MEMORY;
555 }
556
557 rec = notify->db_onelevel->fetch_locked(
558 notify->db_onelevel, array,
559 make_tdb_data((uint8_t *)fid, sizeof(*fid)));
560 if (rec == NULL) {
561 DEBUG(10, ("notify_remove_onelevel: fetch_locked for %s failed"
562 "\n", file_id_string_tos(fid)));
563 TALLOC_FREE(array);
564 return NT_STATUS_INTERNAL_DB_CORRUPTION;
565 }
566
567 blob.data = (uint8_t *)rec->value.dptr;
568 blob.length = rec->value.dsize;
569
570 if (blob.length > 0) {
571 ndr_err = ndr_pull_struct_blob(
572 &blob, array, NULL, array,
573 (ndr_pull_flags_fn_t)ndr_pull_notify_entry_array);
574 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
575 DEBUG(10, ("ndr_pull_notify_entry_array failed: %s\n",
576 ndr_errstr(ndr_err)));
577 TALLOC_FREE(array);
578 return ndr_map_error2ntstatus(ndr_err);
579 }
580 if (DEBUGLEVEL >= 10) {
581 DEBUG(10, ("notify_remove_onelevel:\n"));
582 NDR_PRINT_DEBUG(notify_entry_array, array);
583 }
584 }
585
586 for (i=0; i<array->num_entries; i++) {
587 if ((private_data == array->entries[i].private_data) &&
588 cluster_id_equal(&notify->server,
589 &array->entries[i].server)) {
590 break;
591 }
592 }
593
594 if (i == array->num_entries) {
595 TALLOC_FREE(array);
596 return NT_STATUS_OBJECT_NAME_NOT_FOUND;
597 }
598
599 array->entries[i] = array->entries[array->num_entries-1];
600 array->num_entries -= 1;
601
602 if (array->num_entries == 0) {
603 rec->delete_rec(rec);
604 TALLOC_FREE(array);
605 return NT_STATUS_OK;
606 }
607
608 ndr_err = ndr_push_struct_blob(
609 &blob, rec, NULL, array,
610 (ndr_push_flags_fn_t)ndr_push_notify_entry_array);
611 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
612 DEBUG(10, ("ndr_push_notify_entry_array failed: %s\n",
613 ndr_errstr(ndr_err)));
614 TALLOC_FREE(array);
615 return ndr_map_error2ntstatus(ndr_err);
616 }
617
618 if (DEBUGLEVEL >= 10) {
619 DEBUG(10, ("notify_add_onelevel:\n"));
620 NDR_PRINT_DEBUG(notify_entry_array, array);
621 }
622
623 dbuf.dptr = blob.data;
624 dbuf.dsize = blob.length;
625
626 status = rec->store(rec, dbuf, TDB_REPLACE);
627 TALLOC_FREE(array);
628 if (!NT_STATUS_IS_OK(status)) {
629 DEBUG(10, ("notify_add_onelevel: store failed: %s\n",
630 nt_errstr(status)));
631 return status;
632 }
633 return NT_STATUS_OK;
634}
635
636/*
637 remove a notify watch. Called when the directory handle is closed
638*/
639NTSTATUS notify_remove(struct notify_context *notify, void *private_data)
640{
641 NTSTATUS status;
642 struct notify_list *listel;
643 int i, depth;
644 struct notify_depth *d;
645 struct db_record *rec;
646
647 /* see if change notify is enabled at all */
648 if (notify == NULL) {
649 return NT_STATUS_NOT_IMPLEMENTED;
650 }
651
652 for (listel=notify->list;listel;listel=listel->next) {
653 if (listel->private_data == private_data) {
654 DLIST_REMOVE(notify->list, listel);
655 break;
656 }
657 }
658 if (listel == NULL) {
659 return NT_STATUS_OBJECT_NAME_NOT_FOUND;
660 }
661
662 depth = listel->depth;
663
664 talloc_free(listel);
665
666 status = notify_fetch_locked(notify, &rec);
667 NT_STATUS_NOT_OK_RETURN(status);
668
669 status = notify_load(notify, rec);
670 if (!NT_STATUS_IS_OK(status)) {
671 talloc_free(rec);
672 return status;
673 }
674
675 if (depth >= notify->array->num_depths) {
676 talloc_free(rec);
677 return NT_STATUS_OBJECT_NAME_NOT_FOUND;
678 }
679
680 /* we only have to search at the depth of this element */
681 d = &notify->array->depth[depth];
682
683 for (i=0;i<d->num_entries;i++) {
684 if (private_data == d->entries[i].private_data &&
685 cluster_id_equal(&notify->server, &d->entries[i].server)) {
686 break;
687 }
688 }
689 if (i == d->num_entries) {
690 talloc_free(rec);
691 return NT_STATUS_OBJECT_NAME_NOT_FOUND;
692 }
693
694 if (i < d->num_entries-1) {
695 memmove(&d->entries[i], &d->entries[i+1],
696 sizeof(d->entries[i])*(d->num_entries-(i+1)));
697 }
698 d->num_entries--;
699
700 status = notify_save(notify, rec);
701
702 talloc_free(rec);
703
704 return status;
705}
706
707/*
708 remove all notify watches for a messaging server
709*/
710static NTSTATUS notify_remove_all(struct notify_context *notify,
711 const struct server_id *server)
712{
713 NTSTATUS status;
714 int i, depth, del_count=0;
715 struct db_record *rec;
716
717 status = notify_fetch_locked(notify, &rec);
718 NT_STATUS_NOT_OK_RETURN(status);
719
720 status = notify_load(notify, rec);
721 if (!NT_STATUS_IS_OK(status)) {
722 talloc_free(rec);
723 return status;
724 }
725
726 /* we have to search for all entries across all depths, looking for matches
727 for the server id */
728 for (depth=0;depth<notify->array->num_depths;depth++) {
729 struct notify_depth *d = &notify->array->depth[depth];
730 for (i=0;i<d->num_entries;i++) {
731 if (cluster_id_equal(server, &d->entries[i].server)) {
732 if (i < d->num_entries-1) {
733 memmove(&d->entries[i], &d->entries[i+1],
734 sizeof(d->entries[i])*(d->num_entries-(i+1)));
735 }
736 i--;
737 d->num_entries--;
738 del_count++;
739 }
740 }
741 }
742
743 if (del_count > 0) {
744 status = notify_save(notify, rec);
745 }
746
747 talloc_free(rec);
748
749 return status;
750}
751
752
753/*
754 send a notify message to another messaging server
755*/
756static NTSTATUS notify_send(struct notify_context *notify, struct notify_entry *e,
757 const char *path, uint32_t action)
758{
759 struct notify_event ev;
760 DATA_BLOB data;
761 NTSTATUS status;
762 enum ndr_err_code ndr_err;
763 TALLOC_CTX *tmp_ctx;
764
765 ev.action = action;
766 ev.path = path;
767 ev.private_data = e->private_data;
768
769 tmp_ctx = talloc_new(notify);
770
771 ndr_err = ndr_push_struct_blob(&data, tmp_ctx, NULL, &ev,
772 (ndr_push_flags_fn_t)ndr_push_notify_event);
773 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
774 talloc_free(tmp_ctx);
775 return ndr_map_error2ntstatus(ndr_err);
776 }
777
778 status = messaging_send(notify->messaging_ctx, e->server,
779 MSG_PVFS_NOTIFY, &data);
780 talloc_free(tmp_ctx);
781 return status;
782}
783
784void notify_onelevel(struct notify_context *notify, uint32_t action,
785 uint32_t filter, struct file_id fid, const char *name)
786{
787 struct notify_entry_array *array;
788 TDB_DATA dbuf;
789 DATA_BLOB blob;
790 bool have_dead_entries = false;
791 int i;
792
793 if (notify == NULL) {
794 return;
795 }
796
797 array = talloc_zero(talloc_tos(), struct notify_entry_array);
798 if (array == NULL) {
799 return;
800 }
801
802 if (notify->db_onelevel->fetch(
803 notify->db_onelevel, array,
804 make_tdb_data((uint8_t *)&fid, sizeof(fid)),
805 &dbuf) == -1) {
806 TALLOC_FREE(array);
807 return;
808 }
809
810 blob.data = (uint8 *)dbuf.dptr;
811 blob.length = dbuf.dsize;
812
813 if (blob.length > 0) {
814 enum ndr_err_code ndr_err;
815 ndr_err = ndr_pull_struct_blob(
816 &blob, array, NULL, array,
817 (ndr_pull_flags_fn_t)ndr_pull_notify_entry_array);
818 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
819 DEBUG(10, ("ndr_pull_notify_entry_array failed: %s\n",
820 ndr_errstr(ndr_err)));
821 TALLOC_FREE(array);
822 return;
823 }
824 if (DEBUGLEVEL >= 10) {
825 DEBUG(10, ("notify_onelevel:\n"));
826 NDR_PRINT_DEBUG(notify_entry_array, array);
827 }
828 }
829
830 for (i=0; i<array->num_entries; i++) {
831 struct notify_entry *e = &array->entries[i];
832
833 if ((e->filter & filter) != 0) {
834 NTSTATUS status;
835
836 status = notify_send(notify, e, name, action);
837 if (NT_STATUS_EQUAL(
838 status, NT_STATUS_INVALID_HANDLE)) {
839 /*
840 * Mark the entry as dead. All entries have a
841 * path set. The marker used here is setting
842 * that to NULL.
843 */
844 e->path = NULL;
845 have_dead_entries = true;
846 }
847 }
848 }
849
850 if (!have_dead_entries) {
851 TALLOC_FREE(array);
852 return;
853 }
854
855 for (i=0; i<array->num_entries; i++) {
856 struct notify_entry *e = &array->entries[i];
857 if (e->path != NULL) {
858 continue;
859 }
860 DEBUG(10, ("Deleting notify entries for process %s because "
861 "it's gone\n", procid_str_static(&e->server)));
862 /*
863 * Potential TODO: This might need optimizing,
864 * notify_remove_onelevel() does a fetch_locked() operation at
865 * every call. But this would only matter if a process with
866 * MANY notifies has died without shutting down properly.
867 */
868 notify_remove_onelevel(notify, &e->dir_id, e->private_data);
869 }
870
871 TALLOC_FREE(array);
872 return;
873}
874
875/*
876 trigger a notify message for anyone waiting on a matching event
877
878 This function is called a lot, and needs to be very fast. The unusual data structure
879 and traversal is designed to be fast in the average case, even for large numbers of
880 notifies
881*/
882void notify_trigger(struct notify_context *notify,
883 uint32_t action, uint32_t filter, const char *path)
884{
885 NTSTATUS status;
886 int depth;
887 const char *p, *next_p;
888
889 DEBUG(10, ("notify_trigger called action=0x%x, filter=0x%x, "
890 "path=%s\n", (unsigned)action, (unsigned)filter, path));
891
892 /* see if change notify is enabled at all */
893 if (notify == NULL) {
894 return;
895 }
896
897 again:
898 status = notify_load(notify, NULL);
899 if (!NT_STATUS_IS_OK(status)) {
900 return;
901 }
902
903 /* loop along the given path, working with each directory depth separately */
904 for (depth=0,p=path;
905 p && depth < notify->array->num_depths;
906 p=next_p,depth++) {
907 int p_len = p - path;
908 int min_i, max_i, i;
909 struct notify_depth *d = &notify->array->depth[depth];
910 next_p = strchr(p+1, '/');
911
912 /* see if there are any entries at this depth */
913 if (d->num_entries == 0) continue;
914
915 /* try to skip based on the maximum mask. If next_p is
916 NULL then we know it will be a 'this directory'
917 match, otherwise it must be a subdir match */
918 if (next_p != NULL) {
919 if (0 == (filter & d->max_mask_subdir)) {
920 continue;
921 }
922 } else {
923 if (0 == (filter & d->max_mask)) {
924 continue;
925 }
926 }
927
928 /* we know there is an entry here worth looking
929 for. Use a bisection search to find the first entry
930 with a matching path */
931 min_i = 0;
932 max_i = d->num_entries-1;
933
934 while (min_i < max_i) {
935 struct notify_entry *e;
936 int cmp;
937 i = (min_i+max_i)/2;
938 e = &d->entries[i];
939 cmp = strncmp(path, e->path, p_len);
940 if (cmp == 0) {
941 if (p_len == e->path_len) {
942 max_i = i;
943 } else {
944 max_i = i-1;
945 }
946 } else if (cmp < 0) {
947 max_i = i-1;
948 } else {
949 min_i = i+1;
950 }
951 }
952
953 if (min_i != max_i) {
954 /* none match */
955 continue;
956 }
957
958 /* we now know that the entries start at min_i */
959 for (i=min_i;i<d->num_entries;i++) {
960 struct notify_entry *e = &d->entries[i];
961 if (p_len != e->path_len ||
962 strncmp(path, e->path, p_len) != 0) break;
963 if (next_p != NULL) {
964 if (0 == (filter & e->subdir_filter)) {
965 continue;
966 }
967 } else {
968 if (0 == (filter & e->filter)) {
969 continue;
970 }
971 }
972 status = notify_send(notify, e, path + e->path_len + 1,
973 action);
974
975 if (NT_STATUS_EQUAL(
976 status, NT_STATUS_INVALID_HANDLE)) {
977 struct server_id server = e->server;
978
979 DEBUG(10, ("Deleting notify entries for "
980 "process %s because it's gone\n",
981 procid_str_static(&e->server)));
982 notify_remove_all(notify, &server);
983 goto again;
984 }
985 }
986 }
987}
Note: See TracBrowser for help on using the repository browser.