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dwrite: Use E_NOT_SUFFICIENT_BUFFER definition.
[wine.git] / server / change.c
blob3ac70a43729b032055fca110523f095938d1407f
1 /*
2 * Server-side change notification management
3 *
4 * Copyright (C) 1998 Alexandre Julliard
5 * Copyright (C) 2006 Mike McCormack
6 *
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with this library; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
20 */
21
22 #include "config.h"
23 #include "wine/port.h"
24
25 #include <assert.h>
26 #include <fcntl.h>
27 #include <stdio.h>
28 #include <stdlib.h>
29 #include <signal.h>
30 #include <sys/stat.h>
31 #include <sys/types.h>
32 #include <limits.h>
33 #include <dirent.h>
34 #include <errno.h>
35 #ifdef HAVE_POLL_H
36 # include <poll.h>
37 #endif
38
39 #include "ntstatus.h"
40 #define WIN32_NO_STATUS
41 #include "windef.h"
42
43 #include "file.h"
44 #include "handle.h"
45 #include "thread.h"
46 #include "request.h"
47 #include "process.h"
48 #include "security.h"
49 #include "winternl.h"
50
51 /* dnotify support */
52
53 #ifdef linux
54 #ifndef F_NOTIFY
55 #define F_NOTIFY 1026
56 #define DN_ACCESS 0x00000001 /* File accessed */
57 #define DN_MODIFY 0x00000002 /* File modified */
58 #define DN_CREATE 0x00000004 /* File created */
59 #define DN_DELETE 0x00000008 /* File removed */
60 #define DN_RENAME 0x00000010 /* File renamed */
61 #define DN_ATTRIB 0x00000020 /* File changed attributes */
62 #define DN_MULTISHOT 0x80000000 /* Don't remove notifier */
63 #endif
64 #endif
65
66 /* inotify support */
67
68 #ifdef HAVE_SYS_INOTIFY_H
69 #include <sys/inotify.h>
70 #define USE_INOTIFY
71 #elif defined(__linux__) && defined(__i386__)
72
73 #define SYS_inotify_init 291
74 #define SYS_inotify_add_watch 292
75 #define SYS_inotify_rm_watch 293
76
77 struct inotify_event {
78 int wd;
79 unsigned int mask;
80 unsigned int cookie;
81 unsigned int len;
82 char name[1];
83 };
84
85 #define IN_ACCESS 0x00000001
86 #define IN_MODIFY 0x00000002
87 #define IN_ATTRIB 0x00000004
88 #define IN_CLOSE_WRITE 0x00000008
89 #define IN_CLOSE_NOWRITE 0x00000010
90 #define IN_OPEN 0x00000020
91 #define IN_MOVED_FROM 0x00000040
92 #define IN_MOVED_TO 0x00000080
93 #define IN_CREATE 0x00000100
94 #define IN_DELETE 0x00000200
95 #define IN_DELETE_SELF 0x00000400
96
97 #define IN_ISDIR 0x40000000
98
99 static inline int inotify_init( void )
100 {
101 return syscall( SYS_inotify_init );
102 }
103
104 static inline int inotify_add_watch( int fd, const char *name, unsigned int mask )
105 {
106 return syscall( SYS_inotify_add_watch, fd, name, mask );
107 }
108
109 static inline int inotify_rm_watch( int fd, int wd )
110 {
111 return syscall( SYS_inotify_rm_watch, fd, wd );
112 }
113
114 #define USE_INOTIFY
115
116 #endif
117
118 struct inode;
119
120 static void free_inode( struct inode *inode );
121
122 static struct fd *inotify_fd;
123
124 struct change_record {
125 struct list entry;
126 unsigned int cookie;
127 struct filesystem_event event;
128 };
129
130 struct dir
131 {
132 struct object obj; /* object header */
133 struct fd *fd; /* file descriptor to the directory */
134 mode_t mode; /* file stat.st_mode */
135 uid_t uid; /* file stat.st_uid */
136 struct list entry; /* entry in global change notifications list */
137 unsigned int filter; /* notification filter */
138 int notified; /* SIGIO counter */
139 int want_data; /* return change data */
140 int subtree; /* do we want to watch subdirectories? */
141 struct list change_records; /* data for the change */
142 struct list in_entry; /* entry in the inode dirs list */
143 struct inode *inode; /* inode of the associated directory */
144 };
145
146 static struct fd *dir_get_fd( struct object *obj );
147 static struct security_descriptor *dir_get_sd( struct object *obj );
148 static int dir_set_sd( struct object *obj, const struct security_descriptor *sd,
149 unsigned int set_info );
150 static void dir_dump( struct object *obj, int verbose );
151 static void dir_destroy( struct object *obj );
152
153 static const struct object_ops dir_ops =
154 {
155 sizeof(struct dir), /* size */
156 dir_dump, /* dump */
157 no_get_type, /* get_type */
158 add_queue, /* add_queue */
159 remove_queue, /* remove_queue */
160 default_fd_signaled, /* signaled */
161 no_satisfied, /* satisfied */
162 no_signal, /* signal */
163 dir_get_fd, /* get_fd */
164 default_fd_map_access, /* map_access */
165 dir_get_sd, /* get_sd */
166 dir_set_sd, /* set_sd */
167 no_lookup_name, /* lookup_name */
168 no_open_file, /* open_file */
169 fd_close_handle, /* close_handle */
170 dir_destroy /* destroy */
171 };
172
173 static int dir_get_poll_events( struct fd *fd );
174 static enum server_fd_type dir_get_fd_type( struct fd *fd );
175
176 static const struct fd_ops dir_fd_ops =
177 {
178 dir_get_poll_events, /* get_poll_events */
179 default_poll_event, /* poll_event */
180 no_flush, /* flush */
181 dir_get_fd_type, /* get_fd_type */
182 default_fd_ioctl, /* ioctl */
183 default_fd_queue_async, /* queue_async */
184 default_fd_reselect_async, /* reselect_async */
185 default_fd_cancel_async /* cancel_async */
186 };
187
188 static struct list change_list = LIST_INIT(change_list);
189
190 static void dnotify_adjust_changes( struct dir *dir )
191 {
192 #if defined(F_SETSIG) && defined(F_NOTIFY)
193 int fd = get_unix_fd( dir->fd );
194 unsigned int filter = dir->filter;
195 unsigned int val;
196 if ( 0 > fcntl( fd, F_SETSIG, SIGIO) )
197 return;
198
199 val = DN_MULTISHOT;
200 if (filter & FILE_NOTIFY_CHANGE_FILE_NAME)
201 val |= DN_RENAME | DN_DELETE | DN_CREATE;
202 if (filter & FILE_NOTIFY_CHANGE_DIR_NAME)
203 val |= DN_RENAME | DN_DELETE | DN_CREATE;
204 if (filter & FILE_NOTIFY_CHANGE_ATTRIBUTES)
205 val |= DN_ATTRIB;
206 if (filter & FILE_NOTIFY_CHANGE_SIZE)
207 val |= DN_MODIFY;
208 if (filter & FILE_NOTIFY_CHANGE_LAST_WRITE)
209 val |= DN_MODIFY;
210 if (filter & FILE_NOTIFY_CHANGE_LAST_ACCESS)
211 val |= DN_ACCESS;
212 if (filter & FILE_NOTIFY_CHANGE_CREATION)
213 val |= DN_CREATE;
214 if (filter & FILE_NOTIFY_CHANGE_SECURITY)
215 val |= DN_ATTRIB;
216 fcntl( fd, F_NOTIFY, val );
217 #endif
218 }
219
220 /* insert change in the global list */
221 static inline void insert_change( struct dir *dir )
222 {
223 sigset_t sigset;
224
225 sigemptyset( &sigset );
226 sigaddset( &sigset, SIGIO );
227 sigprocmask( SIG_BLOCK, &sigset, NULL );
228 list_add_head( &change_list, &dir->entry );
229 sigprocmask( SIG_UNBLOCK, &sigset, NULL );
230 }
231
232 /* remove change from the global list */
233 static inline void remove_change( struct dir *dir )
234 {
235 sigset_t sigset;
236
237 sigemptyset( &sigset );
238 sigaddset( &sigset, SIGIO );
239 sigprocmask( SIG_BLOCK, &sigset, NULL );
240 list_remove( &dir->entry );
241 sigprocmask( SIG_UNBLOCK, &sigset, NULL );
242 }
243
244 static void dir_dump( struct object *obj, int verbose )
245 {
246 struct dir *dir = (struct dir *)obj;
247 assert( obj->ops == &dir_ops );
248 fprintf( stderr, "Dirfile fd=%p filter=%08x\n", dir->fd, dir->filter );
249 }
250
251 /* enter here directly from SIGIO signal handler */
252 void do_change_notify( int unix_fd )
253 {
254 struct dir *dir;
255
256 /* FIXME: this is O(n) ... probably can be improved */
257 LIST_FOR_EACH_ENTRY( dir, &change_list, struct dir, entry )
258 {
259 if (get_unix_fd( dir->fd ) != unix_fd) continue;
260 interlocked_xchg_add( &dir->notified, 1 );
261 break;
262 }
263 }
264
265 /* SIGIO callback, called synchronously with the poll loop */
266 void sigio_callback(void)
267 {
268 struct dir *dir;
269
270 LIST_FOR_EACH_ENTRY( dir, &change_list, struct dir, entry )
271 {
272 if (interlocked_xchg( &dir->notified, 0 ))
273 fd_async_wake_up( dir->fd, ASYNC_TYPE_WAIT, STATUS_NOTIFY_ENUM_DIR );
274 }
275 }
276
277 static struct fd *dir_get_fd( struct object *obj )
278 {
279 struct dir *dir = (struct dir *)obj;
280 assert( obj->ops == &dir_ops );
281 return (struct fd *)grab_object( dir->fd );
282 }
283
284 static int get_dir_unix_fd( struct dir *dir )
285 {
286 return get_unix_fd( dir->fd );
287 }
288
289 static struct security_descriptor *dir_get_sd( struct object *obj )
290 {
291 struct dir *dir = (struct dir *)obj;
292 int unix_fd;
293 struct stat st;
294 struct security_descriptor *sd;
295 assert( obj->ops == &dir_ops );
296
297 unix_fd = get_dir_unix_fd( dir );
298
299 if (unix_fd == -1 || fstat( unix_fd, &st ) == -1)
300 return obj->sd;
301
302 /* mode and uid the same? if so, no need to re-generate security descriptor */
303 if (obj->sd &&
304 (st.st_mode & (S_IRWXU|S_IRWXO)) == (dir->mode & (S_IRWXU|S_IRWXO)) &&
305 (st.st_uid == dir->uid))
306 return obj->sd;
307
308 sd = mode_to_sd( st.st_mode,
309 security_unix_uid_to_sid( st.st_uid ),
310 token_get_primary_group( current->process->token ));
311 if (!sd) return obj->sd;
312
313 dir->mode = st.st_mode;
314 dir->uid = st.st_uid;
315 free( obj->sd );
316 obj->sd = sd;
317 return sd;
318 }
319
320 static int dir_set_sd( struct object *obj, const struct security_descriptor *sd,
321 unsigned int set_info )
322 {
323 struct dir *dir = (struct dir *)obj;
324 const SID *owner;
325 struct stat st;
326 mode_t mode;
327 int unix_fd;
328
329 assert( obj->ops == &dir_ops );
330
331 unix_fd = get_dir_unix_fd( dir );
332
333 if (unix_fd == -1 || fstat( unix_fd, &st ) == -1) return 1;
334
335 if (set_info & OWNER_SECURITY_INFORMATION)
336 {
337 owner = sd_get_owner( sd );
338 if (!owner)
339 {
340 set_error( STATUS_INVALID_SECURITY_DESCR );
341 return 0;
342 }
343 if (!obj->sd || !security_equal_sid( owner, sd_get_owner( obj->sd ) ))
344 {
345 /* FIXME: get Unix uid and call fchown */
346 }
347 }
348 else if (obj->sd)
349 owner = sd_get_owner( obj->sd );
350 else
351 owner = token_get_user( current->process->token );
352
353 if (set_info & DACL_SECURITY_INFORMATION)
354 {
355 /* keep the bits that we don't map to access rights in the ACL */
356 mode = st.st_mode & (S_ISUID|S_ISGID|S_ISVTX);
357 mode |= sd_to_mode( sd, owner );
358
359 if (((st.st_mode ^ mode) & (S_IRWXU|S_IRWXG|S_IRWXO)) && fchmod( unix_fd, mode ) == -1)
360 {
361 file_set_error();
362 return 0;
363 }
364 }
365 return 1;
366 }
367
368 static struct change_record *get_first_change_record( struct dir *dir )
369 {
370 struct list *ptr = list_head( &dir->change_records );
371 if (!ptr) return NULL;
372 list_remove( ptr );
373 return LIST_ENTRY( ptr, struct change_record, entry );
374 }
375
376 static void dir_destroy( struct object *obj )
377 {
378 struct change_record *record;
379 struct dir *dir = (struct dir *)obj;
380 assert (obj->ops == &dir_ops);
381
382 if (dir->filter)
383 remove_change( dir );
384
385 if (dir->inode)
386 {
387 list_remove( &dir->in_entry );
388 free_inode( dir->inode );
389 }
390
391 while ((record = get_first_change_record( dir ))) free( record );
392
393 release_object( dir->fd );
394
395 if (inotify_fd && list_empty( &change_list ))
396 {
397 release_object( inotify_fd );
398 inotify_fd = NULL;
399 }
400 }
401
402 struct dir *get_dir_obj( struct process *process, obj_handle_t handle, unsigned int access )
403 {
404 return (struct dir *)get_handle_obj( process, handle, access, &dir_ops );
405 }
406
407 static int dir_get_poll_events( struct fd *fd )
408 {
409 return 0;
410 }
411
412 static enum server_fd_type dir_get_fd_type( struct fd *fd )
413 {
414 return FD_TYPE_DIR;
415 }
416
417 #ifdef USE_INOTIFY
418
419 #define HASH_SIZE 31
420
421 struct inode {
422 struct list ch_entry; /* entry in the children list */
423 struct list children; /* children of this inode */
424 struct inode *parent; /* parent of this inode */
425 struct list dirs; /* directory handles watching this inode */
426 struct list ino_entry; /* entry in the inode hash */
427 struct list wd_entry; /* entry in the watch descriptor hash */
428 dev_t dev; /* device number */
429 ino_t ino; /* device's inode number */
430 int wd; /* inotify's watch descriptor */
431 char *name; /* basename name of the inode */
432 };
433
434 static struct list inode_hash[ HASH_SIZE ];
435 static struct list wd_hash[ HASH_SIZE ];
436
437 static int inotify_add_dir( char *path, unsigned int filter );
438
439 static struct inode *inode_from_wd( int wd )
440 {
441 struct list *bucket = &wd_hash[ wd % HASH_SIZE ];
442 struct inode *inode;
443
444 LIST_FOR_EACH_ENTRY( inode, bucket, struct inode, wd_entry )
445 if (inode->wd == wd)
446 return inode;
447
448 return NULL;
449 }
450
451 static inline struct list *get_hash_list( dev_t dev, ino_t ino )
452 {
453 return &inode_hash[ (ino ^ dev) % HASH_SIZE ];
454 }
455
456 static struct inode *find_inode( dev_t dev, ino_t ino )
457 {
458 struct list *bucket = get_hash_list( dev, ino );
459 struct inode *inode;
460
461 LIST_FOR_EACH_ENTRY( inode, bucket, struct inode, ino_entry )
462 if (inode->ino == ino && inode->dev == dev)
463 return inode;
464
465 return NULL;
466 }
467
468 static struct inode *create_inode( dev_t dev, ino_t ino )
469 {
470 struct inode *inode;
471
472 inode = malloc( sizeof *inode );
473 if (inode)
474 {
475 list_init( &inode->children );
476 list_init( &inode->dirs );
477 inode->ino = ino;
478 inode->dev = dev;
479 inode->wd = -1;
480 inode->parent = NULL;
481 inode->name = NULL;
482 list_add_tail( get_hash_list( dev, ino ), &inode->ino_entry );
483 }
484 return inode;
485 }
486
487 static struct inode *get_inode( dev_t dev, ino_t ino )
488 {
489 struct inode *inode;
490
491 inode = find_inode( dev, ino );
492 if (inode)
493 return inode;
494 return create_inode( dev, ino );
495 }
496
497 static void inode_set_wd( struct inode *inode, int wd )
498 {
499 if (inode->wd != -1)
500 list_remove( &inode->wd_entry );
501 inode->wd = wd;
502 list_add_tail( &wd_hash[ wd % HASH_SIZE ], &inode->wd_entry );
503 }
504
505 static void inode_set_name( struct inode *inode, const char *name )
506 {
507 free (inode->name);
508 inode->name = name ? strdup( name ) : NULL;
509 }
510
511 static void free_inode( struct inode *inode )
512 {
513 int subtree = 0, watches = 0;
514 struct inode *tmp, *next;
515 struct dir *dir;
516
517 LIST_FOR_EACH_ENTRY( dir, &inode->dirs, struct dir, in_entry )
518 {
519 subtree |= dir->subtree;
520 watches++;
521 }
522
523 if (!subtree && !inode->parent)
524 {
525 LIST_FOR_EACH_ENTRY_SAFE( tmp, next, &inode->children,
526 struct inode, ch_entry )
527 {
528 assert( tmp != inode );
529 assert( tmp->parent == inode );
530 free_inode( tmp );
531 }
532 }
533
534 if (watches)
535 return;
536
537 if (inode->parent)
538 list_remove( &inode->ch_entry );
539
540 /* disconnect remaining children from the parent */
541 LIST_FOR_EACH_ENTRY_SAFE( tmp, next, &inode->children, struct inode, ch_entry )
542 {
543 list_remove( &tmp->ch_entry );
544 tmp->parent = NULL;
545 }
546
547 if (inode->wd != -1)
548 {
549 inotify_rm_watch( get_unix_fd( inotify_fd ), inode->wd );
550 list_remove( &inode->wd_entry );
551 }
552 list_remove( &inode->ino_entry );
553
554 free( inode->name );
555 free( inode );
556 }
557
558 static struct inode *inode_add( struct inode *parent,
559 dev_t dev, ino_t ino, const char *name )
560 {
561 struct inode *inode;
562
563 inode = get_inode( dev, ino );
564 if (!inode)
565 return NULL;
566
567 if (!inode->parent)
568 {
569 list_add_tail( &parent->children, &inode->ch_entry );
570 inode->parent = parent;
571 assert( inode != parent );
572 }
573 inode_set_name( inode, name );
574
575 return inode;
576 }
577
578 static struct inode *inode_from_name( struct inode *inode, const char *name )
579 {
580 struct inode *i;
581
582 LIST_FOR_EACH_ENTRY( i, &inode->children, struct inode, ch_entry )
583 if (i->name && !strcmp( i->name, name ))
584 return i;
585 return NULL;
586 }
587
588 static int inotify_get_poll_events( struct fd *fd );
589 static void inotify_poll_event( struct fd *fd, int event );
590
591 static const struct fd_ops inotify_fd_ops =
592 {
593 inotify_get_poll_events, /* get_poll_events */
594 inotify_poll_event, /* poll_event */
595 NULL, /* flush */
596 NULL, /* get_fd_type */
597 NULL, /* ioctl */
598 NULL, /* queue_async */
599 NULL, /* reselect_async */
600 NULL, /* cancel_async */
601 };
602
603 static int inotify_get_poll_events( struct fd *fd )
604 {
605 return POLLIN;
606 }
607
608 static void inotify_do_change_notify( struct dir *dir, unsigned int action,
609 unsigned int cookie, const char *relpath )
610 {
611 struct change_record *record;
612
613 assert( dir->obj.ops == &dir_ops );
614
615 if (dir->want_data)
616 {
617 size_t len = strlen(relpath);
618 record = malloc( offsetof(struct change_record, event.name[len]) );
619 if (!record)
620 return;
621
622 record->cookie = cookie;
623 record->event.action = action;
624 memcpy( record->event.name, relpath, len );
625 record->event.len = len;
626
627 list_add_tail( &dir->change_records, &record->entry );
628 }
629
630 fd_async_wake_up( dir->fd, ASYNC_TYPE_WAIT, STATUS_ALERTED );
631 }
632
633 static unsigned int filter_from_event( struct inotify_event *ie )
634 {
635 unsigned int filter = 0;
636
637 if (ie->mask & (IN_MOVED_FROM | IN_MOVED_TO | IN_DELETE | IN_CREATE))
638 filter |= FILE_NOTIFY_CHANGE_FILE_NAME | FILE_NOTIFY_CHANGE_DIR_NAME;
639 if (ie->mask & IN_MODIFY)
640 filter |= FILE_NOTIFY_CHANGE_SIZE | FILE_NOTIFY_CHANGE_LAST_WRITE;
641 if (ie->mask & IN_ATTRIB)
642 filter |= FILE_NOTIFY_CHANGE_ATTRIBUTES | FILE_NOTIFY_CHANGE_SECURITY;
643 if (ie->mask & IN_ACCESS)
644 filter |= FILE_NOTIFY_CHANGE_LAST_ACCESS;
645 if (ie->mask & IN_CREATE)
646 filter |= FILE_NOTIFY_CHANGE_CREATION;
647
648 if (ie->mask & IN_ISDIR)
649 filter &= ~FILE_NOTIFY_CHANGE_FILE_NAME;
650 else
651 filter &= ~FILE_NOTIFY_CHANGE_DIR_NAME;
652
653 return filter;
654 }
655
656 /* scan up the parent directories for watches */
657 static unsigned int filter_from_inode( struct inode *inode, int is_parent )
658 {
659 unsigned int filter = 0;
660 struct dir *dir;
661
662 /* combine filters from parents watching subtrees */
663 while (inode)
664 {
665 LIST_FOR_EACH_ENTRY( dir, &inode->dirs, struct dir, in_entry )
666 if (dir->subtree || !is_parent)
667 filter |= dir->filter;
668 is_parent = 1;
669 inode = inode->parent;
670 }
671
672 return filter;
673 }
674
675 static char *inode_get_path( struct inode *inode, int sz )
676 {
677 struct list *head;
678 char *path;
679 int len;
680
681 if (!inode)
682 return NULL;
683
684 head = list_head( &inode->dirs );
685 if (head)
686 {
687 int unix_fd = get_unix_fd( LIST_ENTRY( head, struct dir, in_entry )->fd );
688 path = malloc ( 32 + sz );
689 if (path)
690 sprintf( path, "/proc/self/fd/%u/", unix_fd );
691 return path;
692 }
693
694 if (!inode->name)
695 return NULL;
696
697 len = strlen( inode->name );
698 path = inode_get_path( inode->parent, sz + len + 1 );
699 if (!path)
700 return NULL;
701
702 strcat( path, inode->name );
703 strcat( path, "/" );
704
705 return path;
706 }
707
708 static void inode_check_dir( struct inode *parent, const char *name )
709 {
710 char *path;
711 unsigned int filter;
712 struct inode *inode;
713 struct stat st;
714 int wd = -1;
715
716 path = inode_get_path( parent, strlen(name) );
717 if (!path)
718 return;
719
720 strcat( path, name );
721
722 if (stat( path, &st ) < 0)
723 goto end;
724
725 filter = filter_from_inode( parent, 1 );
726 if (!filter)
727 goto end;
728
729 inode = inode_add( parent, st.st_dev, st.st_ino, name );
730 if (!inode || inode->wd != -1)
731 goto end;
732
733 wd = inotify_add_dir( path, filter );
734 if (wd != -1)
735 inode_set_wd( inode, wd );
736 else
737 free_inode( inode );
738
739 end:
740 free( path );
741 }
742
743 static int prepend( char **path, const char *segment )
744 {
745 int extra;
746 char *p;
747
748 extra = strlen( segment ) + 1;
749 if (*path)
750 {
751 int len = strlen( *path ) + 1;
752 p = realloc( *path, len + extra );
753 if (!p) return 0;
754 memmove( &p[ extra ], p, len );
755 p[ extra - 1 ] = '/';
756 memcpy( p, segment, extra - 1 );
757 }
758 else
759 {
760 p = malloc( extra );
761 if (!p) return 0;
762 memcpy( p, segment, extra );
763 }
764
765 *path = p;
766
767 return 1;
768 }
769
770 static void inotify_notify_all( struct inotify_event *ie )
771 {
772 unsigned int filter, action;
773 struct inode *inode, *i;
774 char *path = NULL;
775 struct dir *dir;
776
777 inode = inode_from_wd( ie->wd );
778 if (!inode)
779 {
780 fprintf( stderr, "no inode matches %d\n", ie->wd);
781 return;
782 }
783
784 filter = filter_from_event( ie );
785
786 if (ie->mask & IN_CREATE)
787 {
788 if (ie->mask & IN_ISDIR)
789 inode_check_dir( inode, ie->name );
790
791 action = FILE_ACTION_ADDED;
792 }
793 else if (ie->mask & IN_DELETE)
794 action = FILE_ACTION_REMOVED;
795 else if (ie->mask & IN_MOVED_FROM)
796 action = FILE_ACTION_RENAMED_OLD_NAME;
797 else if (ie->mask & IN_MOVED_TO)
798 action = FILE_ACTION_RENAMED_NEW_NAME;
799 else
800 action = FILE_ACTION_MODIFIED;
801
802 /*
803 * Work our way up the inode hierarchy
804 * extending the relative path as we go
805 * and notifying all recursive watches.
806 */
807 if (!prepend( &path, ie->name ))
808 return;
809
810 for (i = inode; i; i = i->parent)
811 {
812 LIST_FOR_EACH_ENTRY( dir, &i->dirs, struct dir, in_entry )
813 if ((filter & dir->filter) && (i==inode || dir->subtree))
814 inotify_do_change_notify( dir, action, ie->cookie, path );
815
816 if (!i->name || !prepend( &path, i->name ))
817 break;
818 }
819
820 free( path );
821
822 if (ie->mask & IN_DELETE)
823 {
824 i = inode_from_name( inode, ie->name );
825 if (i)
826 free_inode( i );
827 }
828 }
829
830 static void inotify_poll_event( struct fd *fd, int event )
831 {
832 int r, ofs, unix_fd;
833 char buffer[0x1000];
834 struct inotify_event *ie;
835
836 unix_fd = get_unix_fd( fd );
837 r = read( unix_fd, buffer, sizeof buffer );
838 if (r < 0)
839 {
840 fprintf(stderr,"inotify_poll_event(): inotify read failed!\n");
841 return;
842 }
843
844 for( ofs = 0; ofs < r - offsetof(struct inotify_event, name); )
845 {
846 ie = (struct inotify_event*) &buffer[ofs];
847 if (!ie->len)
848 break;
849 ofs += offsetof( struct inotify_event, name[ie->len] );
850 if (ofs > r) break;
851 inotify_notify_all( ie );
852 }
853 }
854
855 static inline struct fd *create_inotify_fd( void )
856 {
857 int unix_fd;
858
859 unix_fd = inotify_init();
860 if (unix_fd<0)
861 return NULL;
862 return create_anonymous_fd( &inotify_fd_ops, unix_fd, NULL, 0 );
863 }
864
865 static int map_flags( unsigned int filter )
866 {
867 unsigned int mask;
868
869 /* always watch these so we can track subdirectories in recursive watches */
870 mask = (IN_MOVED_FROM | IN_MOVED_TO | IN_DELETE | IN_CREATE | IN_DELETE_SELF);
871
872 if (filter & FILE_NOTIFY_CHANGE_ATTRIBUTES)
873 mask |= IN_ATTRIB;
874 if (filter & FILE_NOTIFY_CHANGE_SIZE)
875 mask |= IN_MODIFY;
876 if (filter & FILE_NOTIFY_CHANGE_LAST_WRITE)
877 mask |= IN_MODIFY;
878 if (filter & FILE_NOTIFY_CHANGE_LAST_ACCESS)
879 mask |= IN_ACCESS;
880 if (filter & FILE_NOTIFY_CHANGE_SECURITY)
881 mask |= IN_ATTRIB;
882
883 return mask;
884 }
885
886 static int inotify_add_dir( char *path, unsigned int filter )
887 {
888 int wd = inotify_add_watch( get_unix_fd( inotify_fd ),
889 path, map_flags( filter ) );
890 if (wd != -1)
891 set_fd_events( inotify_fd, POLLIN );
892 return wd;
893 }
894
895 static int init_inotify( void )
896 {
897 int i;
898
899 if (inotify_fd)
900 return 1;
901
902 inotify_fd = create_inotify_fd();
903 if (!inotify_fd)
904 return 0;
905
906 for (i=0; i<HASH_SIZE; i++)
907 {
908 list_init( &inode_hash[i] );
909 list_init( &wd_hash[i] );
910 }
911
912 return 1;
913 }
914
915 static int inotify_adjust_changes( struct dir *dir )
916 {
917 unsigned int filter;
918 struct inode *inode;
919 struct stat st;
920 char path[32];
921 int wd, unix_fd;
922
923 if (!inotify_fd)
924 return 0;
925
926 unix_fd = get_unix_fd( dir->fd );
927
928 inode = dir->inode;
929 if (!inode)
930 {
931 /* check if this fd is already being watched */
932 if (-1 == fstat( unix_fd, &st ))
933 return 0;
934
935 inode = get_inode( st.st_dev, st.st_ino );
936 if (!inode)
937 inode = create_inode( st.st_dev, st.st_ino );
938 if (!inode)
939 return 0;
940 list_add_tail( &inode->dirs, &dir->in_entry );
941 dir->inode = inode;
942 }
943
944 filter = filter_from_inode( inode, 0 );
945
946 sprintf( path, "/proc/self/fd/%u", unix_fd );
947 wd = inotify_add_dir( path, filter );
948 if (wd == -1) return 0;
949
950 inode_set_wd( inode, wd );
951
952 return 1;
953 }
954
955 static char *get_basename( const char *link )
956 {
957 char *buffer, *name = NULL;
958 int r, n = 0x100;
959
960 while (1)
961 {
962 buffer = malloc( n );
963 if (!buffer) return NULL;
964
965 r = readlink( link, buffer, n );
966 if (r < 0)
967 break;
968
969 if (r < n)
970 {
971 name = buffer;
972 break;
973 }
974 free( buffer );
975 n *= 2;
976 }
977
978 if (name)
979 {
980 while (r > 0 && name[ r - 1 ] == '/' )
981 r--;
982 name[ r ] = 0;
983
984 name = strrchr( name, '/' );
985 if (name)
986 name = strdup( &name[1] );
987 }
988
989 free( buffer );
990 return name;
991 }
992
993 static int dir_add_to_existing_notify( struct dir *dir )
994 {
995 struct inode *inode, *parent;
996 unsigned int filter = 0;
997 struct stat st, st_new;
998 char link[35], *name;
999 int wd, unix_fd;
1000
1001 if (!inotify_fd)
1002 return 0;
1003
1004 unix_fd = get_unix_fd( dir->fd );
1005
1006 /* check if it's in the list of inodes we want to watch */
1007 if (-1 == fstat( unix_fd, &st_new ))
1008 return 0;
1009 inode = find_inode( st_new.st_dev, st_new.st_ino );
1010 if (inode)
1011 return 0;
1012
1013 /* lookup the parent */
1014 sprintf( link, "/proc/self/fd/%u/..", unix_fd );
1015 if (-1 == stat( link, &st ))
1016 return 0;
1017
1018 /*
1019 * If there's no parent, stop. We could keep going adding
1020 * ../ to the path until we hit the root of the tree or
1021 * find a recursively watched ancestor.
1022 * Assume it's too expensive to search up the tree for now.
1023 */
1024 parent = find_inode( st.st_dev, st.st_ino );
1025 if (!parent)
1026 return 0;
1027
1028 if (parent->wd == -1)
1029 return 0;
1030
1031 filter = filter_from_inode( parent, 1 );
1032 if (!filter)
1033 return 0;
1034
1035 sprintf( link, "/proc/self/fd/%u", unix_fd );
1036 name = get_basename( link );
1037 if (!name)
1038 return 0;
1039 inode = inode_add( parent, st_new.st_dev, st_new.st_ino, name );
1040 free( name );
1041 if (!inode)
1042 return 0;
1043
1044 /* Couldn't find this inode at the start of the function, must be new */
1045 assert( inode->wd == -1 );
1046
1047 wd = inotify_add_dir( link, filter );
1048 if (wd != -1)
1049 inode_set_wd( inode, wd );
1050
1051 return 1;
1052 }
1053
1054 #else
1055
1056 static int init_inotify( void )
1057 {
1058 return 0;
1059 }
1060
1061 static int inotify_adjust_changes( struct dir *dir )
1062 {
1063 return 0;
1064 }
1065
1066 static void free_inode( struct inode *inode )
1067 {
1068 assert( 0 );
1069 }
1070
1071 static int dir_add_to_existing_notify( struct dir *dir )
1072 {
1073 return 0;
1074 }
1075
1076 #endif /* USE_INOTIFY */
1077
1078 struct object *create_dir_obj( struct fd *fd, unsigned int access, mode_t mode )
1079 {
1080 struct dir *dir;
1081
1082 dir = alloc_object( &dir_ops );
1083 if (!dir)
1084 return NULL;
1085
1086 list_init( &dir->change_records );
1087 dir->filter = 0;
1088 dir->notified = 0;
1089 dir->want_data = 0;
1090 dir->inode = NULL;
1091 grab_object( fd );
1092 dir->fd = fd;
1093 dir->mode = mode;
1094 dir->uid = ~(uid_t)0;
1095 set_fd_user( fd, &dir_fd_ops, &dir->obj );
1096
1097 dir_add_to_existing_notify( dir );
1098
1099 return &dir->obj;
1100 }
1101
1102 /* enable change notifications for a directory */
1103 DECL_HANDLER(read_directory_changes)
1104 {
1105 struct dir *dir;
1106 struct async *async;
1107
1108 if (!req->filter)
1109 {
1110 set_error(STATUS_INVALID_PARAMETER);
1111 return;
1112 }
1113
1114 dir = get_dir_obj( current->process, req->async.handle, 0 );
1115 if (!dir)
1116 return;
1117
1118 /* requests don't timeout */
1119 if (!(async = fd_queue_async( dir->fd, &req->async, ASYNC_TYPE_WAIT ))) goto end;
1120
1121 /* assign it once */
1122 if (!dir->filter)
1123 {
1124 init_inotify();
1125 insert_change( dir );
1126 dir->filter = req->filter;
1127 dir->subtree = req->subtree;
1128 dir->want_data = req->want_data;
1129 }
1130
1131 /* if there's already a change in the queue, send it */
1132 if (!list_empty( &dir->change_records ))
1133 fd_async_wake_up( dir->fd, ASYNC_TYPE_WAIT, STATUS_ALERTED );
1134
1135 /* setup the real notification */
1136 if (!inotify_adjust_changes( dir ))
1137 dnotify_adjust_changes( dir );
1138
1139 release_object( async );
1140 set_error(STATUS_PENDING);
1141
1142 end:
1143 release_object( dir );
1144 }
1145
1146 DECL_HANDLER(read_change)
1147 {
1148 struct change_record *record, *next;
1149 struct dir *dir;
1150 struct list events;
1151 char *data, *event;
1152 int size = 0;
1153
1154 dir = get_dir_obj( current->process, req->handle, 0 );
1155 if (!dir)
1156 return;
1157
1158 list_init( &events );
1159 list_move_tail( &events, &dir->change_records );
1160 release_object( dir );
1161
1162 if (list_empty( &events ))
1163 {
1164 set_error( STATUS_NO_DATA_DETECTED );
1165 return;
1166 }
1167
1168 LIST_FOR_EACH_ENTRY( record, &events, struct change_record, entry )
1169 {
1170 size += (offsetof(struct filesystem_event, name[record->event.len])
1171 + sizeof(int)-1) / sizeof(int) * sizeof(int);
1172 }
1173
1174 if (size > get_reply_max_size())
1175 set_error( STATUS_BUFFER_TOO_SMALL );
1176 else if ((data = mem_alloc( size )) != NULL)
1177 {
1178 event = data;
1179 LIST_FOR_EACH_ENTRY( record, &events, struct change_record, entry )
1180 {
1181 data_size_t len = offsetof( struct filesystem_event, name[record->event.len] );
1182
1183 /* FIXME: rename events are sometimes reported as delete/create */
1184 if (record->event.action == FILE_ACTION_RENAMED_OLD_NAME)
1185 {
1186 struct list *elem = list_next( &events, &record->entry );
1187 if (elem)
1188 next = LIST_ENTRY(elem, struct change_record, entry);
1189
1190 if (elem && next->cookie == record->cookie)
1191 next->cookie = 0;
1192 else
1193 record->event.action = FILE_ACTION_REMOVED;
1194 }
1195 else if (record->event.action == FILE_ACTION_RENAMED_NEW_NAME && record->cookie)
1196 record->event.action = FILE_ACTION_ADDED;
1197
1198 memcpy( event, &record->event, len );
1199 event += len;
1200 if (len % sizeof(int))
1201 {
1202 memset( event, 0, sizeof(int) - len % sizeof(int) );
1203 event += sizeof(int) - len % sizeof(int);
1204 }
1205 }
1206 set_reply_data_ptr( data, size );
1207 }
1208
1209 LIST_FOR_EACH_ENTRY_SAFE( record, next, &events, struct change_record, entry )
1210 {
1211 list_remove( &record->entry );
1212 free( record );
1213 }
1214 }
Windows API implementation