File: | obj-scan-build/ftpfs/../../ftpfs/dir.c |
Location: | line 385, column 5 |
Description: | Value stored to 'err' is never read |
1 | /* Directory operations |
2 | |
3 | Copyright (C) 1997,98,2002 Free Software Foundation, Inc. |
4 | Written by Miles Bader <miles@gnu.org> |
5 | This file is part of the GNU Hurd. |
6 | |
7 | The GNU Hurd is free software; you can redistribute it and/or |
8 | modify it under the terms of the GNU General Public License as |
9 | published by the Free Software Foundation; either version 2, or (at |
10 | your option) any later version. |
11 | |
12 | The GNU Hurd is distributed in the hope that it will be useful, but |
13 | WITHOUT ANY WARRANTY; without even the implied warranty of |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
15 | General Public License for more details. |
16 | |
17 | You should have received a copy of the GNU General Public License |
18 | along with this program; if not, write to the Free Software |
19 | Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA. */ |
20 | |
21 | #include <unistd.h> |
22 | #include <string.h> |
23 | |
24 | #include <hurd/netfs.h> |
25 | |
26 | #include "ftpfs.h" |
27 | #include "ccache.h" |
28 | |
29 | /* Free the directory entry E and all resources it consumes. */ |
30 | void |
31 | free_entry (struct ftpfs_dir_entry *e) |
32 | { |
33 | assert (! e->self_p)((! e->self_p) ? (void) (0) : __assert_fail ("! e->self_p" , "../../ftpfs/dir.c", 33, __PRETTY_FUNCTION__)); /* We should only free deleted nodes. */ |
34 | free (e->name); |
35 | if (e->symlink_target) |
36 | free (e->symlink_target); |
37 | free (e); |
38 | } |
39 | |
40 | /* Put the directory entry E into the hash table HTABLE, of length HTABLE_LEN. */ |
41 | static void |
42 | insert (struct ftpfs_dir_entry *e, |
43 | struct ftpfs_dir_entry **htable, size_t htable_len) |
44 | { |
45 | struct ftpfs_dir_entry **t = &htable[e->hv % htable_len]; |
46 | if (*t) |
47 | (*t)->self_p = &e->next; |
48 | e->next = *t; |
49 | e->self_p = t; |
50 | *t = e; |
51 | } |
52 | |
53 | /* Replace DIR's hashtable with a new one of length NEW_LEN, retaining all |
54 | existing entries. */ |
55 | static error_t |
56 | rehash (struct ftpfs_dir *dir, size_t new_len) |
57 | { |
58 | int i; |
59 | size_t old_len = dir->htable_len; |
60 | struct ftpfs_dir_entry **old_htable = dir->htable; |
61 | struct ftpfs_dir_entry **new_htable = |
62 | malloc (new_len * sizeof (struct ftpfs_dir_entry *)); |
63 | |
64 | if (! new_htable) |
65 | return ENOMEM((0x10 << 26) | ((12) & 0x3fff)); |
66 | |
67 | bzero (new_htable, new_len * sizeof (struct ftpfs_dir_entry *)); |
68 | |
69 | for (i = 0; i < old_len; i++) |
70 | while (old_htable[i]) |
71 | { |
72 | struct ftpfs_dir_entry *e = old_htable[i]; |
73 | |
74 | /* Remove E from the old table (don't bother to fixup |
75 | e->next->self_p). */ |
76 | old_htable[i] = e->next; |
77 | |
78 | insert (e, new_htable, new_len); |
79 | } |
80 | |
81 | free (old_htable); |
82 | |
83 | dir->htable = new_htable; |
84 | dir->htable_len = new_len; |
85 | |
86 | return 0; |
87 | } |
88 | |
89 | /* Calculate NAME's hash value. */ |
90 | static size_t |
91 | hash (const char *name) |
92 | { |
93 | size_t hv = 0; |
94 | while (*name) |
95 | hv = ((hv << 5) + *name++) & 0xFFFFFF; |
96 | return hv; |
97 | } |
98 | |
99 | /* Lookup NAME in DIR and return its entry. If there is no such entry, and |
100 | ADD is true, then a new entry is allocated and returned, otherwise 0 is |
101 | returned (if ADD is true then 0 can be returned if a memory allocation |
102 | error occurs). */ |
103 | struct ftpfs_dir_entry * |
104 | lookup (struct ftpfs_dir *dir, const char *name, int add) |
105 | { |
106 | size_t hv = hash (name); |
107 | struct ftpfs_dir_entry *h = dir->htable[hv % dir->htable_len], *e = h; |
108 | |
109 | while (e && strcmp (name, e->name) != 0) |
110 | e = e->next; |
111 | |
112 | if (!e && add) |
113 | { |
114 | if (dir->num_entries > dir->htable_len) |
115 | /* Grow the hash table. */ |
116 | if (rehash (dir, (dir->htable_len + 1) * 2 - 1) != 0) |
117 | return 0; |
118 | |
119 | e = malloc (sizeof *e); |
120 | if (e) |
121 | { |
122 | e->hv = hv; |
123 | e->name = strdup (name); |
124 | e->node = 0; |
125 | e->dir = dir; |
126 | e->stat_timestamp = 0; |
127 | bzero (&e->stat, sizeof e->stat); |
128 | e->symlink_target = 0; |
129 | e->noent = 0; |
130 | e->valid = 0; |
131 | e->name_timestamp = e->stat_timestamp = 0; |
132 | e->ordered_next = 0; |
133 | e->ordered_self_p = 0; |
134 | e->next = 0; |
135 | e->self_p = 0; |
136 | insert (e, dir->htable, dir->htable_len); |
137 | dir->num_entries++; |
138 | } |
139 | } |
140 | |
141 | return e; |
142 | } |
143 | |
144 | /* Remove E from its position in the ordered_next chain. */ |
145 | static void |
146 | ordered_unlink (struct ftpfs_dir_entry *e) |
147 | { |
148 | if (e->ordered_self_p) |
149 | *e->ordered_self_p = e->ordered_next; |
150 | if (e->ordered_next) |
151 | e->ordered_next->self_p = e->ordered_self_p; |
152 | } |
153 | |
154 | /* Delete E from its directory, freeing any resources it holds. */ |
155 | static void |
156 | delete (struct ftpfs_dir_entry *e, struct ftpfs_dir *dir) |
157 | { |
158 | dir->num_entries--; |
159 | |
160 | /* Take out of the hash chain. */ |
161 | if (e->self_p) |
162 | *e->self_p = e->next; |
163 | if (e->next) |
164 | e->next->self_p = e->self_p; |
165 | |
166 | /* This indicates a deleted entry. */ |
167 | e->self_p = 0; |
168 | e->next = 0; |
169 | |
170 | /* Take out of the directory ordered list. */ |
171 | ordered_unlink (e); |
172 | |
173 | /* If there's a node attached, we'll delete the entry whenever it goes |
174 | away, otherwise, just delete it now. */ |
175 | if (! e->node) |
176 | free_entry (e); |
177 | } |
178 | |
179 | /* Clear the valid bit in all DIR's htable. */ |
180 | static void |
181 | mark (struct ftpfs_dir *dir) |
182 | { |
183 | size_t len = dir->htable_len, i; |
184 | struct ftpfs_dir_entry **htable = dir->htable, *e; |
185 | |
186 | for (i = 0; i < len; i++) |
187 | for (e = htable[i]; e; e = e->next) |
188 | e->valid = 0; |
189 | } |
190 | |
191 | /* Delete any entries in DIR which don't have their valid bit set. */ |
192 | static void |
193 | sweep (struct ftpfs_dir *dir) |
194 | { |
195 | size_t len = dir->htable_len, i; |
196 | struct ftpfs_dir_entry **htable = dir->htable, *e; |
197 | |
198 | for (i = 0; i < len; i++) |
199 | for (e = htable[i]; e; e = e->next) |
200 | if (!e->valid && !e->noent) |
201 | delete (e, dir); |
202 | } |
203 | |
204 | /* Update the directory entry for NAME to reflect ST and SYMLINK_TARGET. |
205 | True is returned if successful, or false if there was a memory allocation |
206 | error. TIMESTAMP is used to record the time of this update. */ |
207 | static void |
208 | update_entry (struct ftpfs_dir_entry *e, const struct stat *st, |
209 | const char *symlink_target, time_t timestamp) |
210 | { |
211 | ino_t ino; |
212 | struct ftpfs *fs = e->dir->fs; |
213 | |
214 | if (e->stat.st_ino) |
215 | ino = e->stat.st_ino; |
216 | else |
217 | ino = fs->next_inode++; |
218 | |
219 | e->name_timestamp = timestamp; |
220 | |
221 | if (st) |
222 | /* The ST and SYMLINK_TARGET parameters are only valid if ST isn't 0. */ |
223 | { |
224 | e->stat = *st; |
225 | e->stat_timestamp = timestamp; |
226 | |
227 | if (!e->symlink_target || !symlink_target |
228 | || strcmp (e->symlink_target, symlink_target) != 0) |
229 | { |
230 | if (e->symlink_target) |
231 | free (e->symlink_target); |
232 | e->symlink_target = symlink_target ? strdup (symlink_target) : 0; |
233 | } |
234 | } |
235 | |
236 | /* The st_ino field is always valid. */ |
237 | e->stat.st_ino = ino; |
238 | e->stat.st_fsid = fs->fsid; |
239 | e->stat.st_fstype = FSTYPE_FTP0x00000005; |
240 | } |
241 | |
242 | /* Add the timestamp TIMESTAMP to the set used to detect bulk stats, and |
243 | return true if there have been enough individual stats recently to call |
244 | for just refetching the whole directory. */ |
245 | static int |
246 | need_bulk_stat (time_t timestamp, struct ftpfs_dir *dir) |
247 | { |
248 | time_t period = dir->fs->params.bulk_stat_period; |
249 | unsigned threshold = dir->fs->params.bulk_stat_threshold; |
250 | |
251 | if (timestamp > dir->bulk_stat_base_stamp + period * 3) |
252 | /* No stats done in a while, just start over. */ |
253 | { |
254 | dir->bulk_stat_count_first_half = 1; |
255 | dir->bulk_stat_count_second_half = 0; |
256 | dir->bulk_stat_base_stamp = (timestamp / period) * period; |
257 | } |
258 | else if (timestamp > dir->bulk_stat_base_stamp + period * 2) |
259 | /* Start a new period, but keep the second half of the old one. */ |
260 | { |
261 | dir->bulk_stat_count_first_half = dir->bulk_stat_count_second_half; |
262 | dir->bulk_stat_count_second_half = 1; |
263 | dir->bulk_stat_base_stamp += period; |
264 | } |
265 | else if (timestamp > dir->bulk_stat_base_stamp + period) |
266 | dir->bulk_stat_count_second_half++; |
267 | else |
268 | dir->bulk_stat_count_first_half++; |
269 | |
270 | return |
271 | (dir->bulk_stat_count_first_half + dir->bulk_stat_count_second_half) |
272 | > threshold; |
273 | } |
274 | |
275 | static void |
276 | reset_bulk_stat_info (struct ftpfs_dir *dir) |
277 | { |
278 | dir->bulk_stat_count_first_half = 0; |
279 | dir->bulk_stat_count_second_half = 0; |
280 | dir->bulk_stat_base_stamp = 0; |
281 | } |
282 | |
283 | /* State shared between ftpfs_dir_refresh and update_ordered_entry. */ |
284 | struct dir_fetch_state |
285 | { |
286 | struct ftpfs_dir *dir; |
287 | time_t timestamp; |
288 | |
289 | /* A pointer to the NEXT-field of the previously seen entry, or a pointer |
290 | to the ORDERED field in the directory if this is the first. */ |
291 | struct ftpfs_dir_entry **prev_entry_next_p; |
292 | }; |
293 | |
294 | /* Update the directory entry for NAME to reflect ST and SYMLINK_TARGET, also |
295 | rearranging the entries to reflect the order in which they are sent from |
296 | the server, and setting their valid bits so that obsolete entries can be |
297 | deleted. HOOK points to the state from ftpfs_dir_fetch. */ |
298 | static error_t |
299 | update_ordered_entry (const char *name, const struct stat *st, |
300 | const char *symlink_target, void *hook) |
301 | { |
302 | struct dir_fetch_state *dfs = hook; |
303 | struct ftpfs_dir_entry *e = lookup (dfs->dir, name, 1); |
304 | |
305 | if (! e) |
306 | return ENOMEM((0x10 << 26) | ((12) & 0x3fff)); |
307 | |
308 | update_entry (e, st, symlink_target, dfs->timestamp); |
309 | e->valid = 1; |
310 | |
311 | if (! e->ordered_self_p) |
312 | /* Position E in the ordered chain following the previously seen entry. */ |
313 | { |
314 | /* The PREV_ENTRY_NEXT_P field holds a pointer to the NEXT-field of the |
315 | previous entry, or a pointer to the ORDERED field in the directory. */ |
316 | e->ordered_self_p = dfs->prev_entry_next_p; |
317 | |
318 | if (*e->ordered_self_p) |
319 | /* Update the self_p pointer of the previous successor. */ |
320 | (*e->ordered_self_p)->ordered_self_p = &e->ordered_next; |
321 | |
322 | /* E comes before the previous successor. */ |
323 | e->ordered_next = *e->ordered_self_p; |
324 | |
325 | *e->ordered_self_p = e; /* Put E there. */ |
326 | } |
327 | |
328 | /* Put the next entry after this one. */ |
329 | dfs->prev_entry_next_p = &e->ordered_next; |
330 | |
331 | return 0; |
332 | } |
333 | |
334 | /* Update the directory entry for NAME, rearranging the entries to reflect |
335 | the order in which they are sent from the server, and setting their valid |
336 | bits so that obsolete entries can be deleted. HOOK points to the state |
337 | from ftpfs_dir_fetch. */ |
338 | static error_t |
339 | update_ordered_name (const char *name, void *hook) |
340 | { |
341 | /* We just do the same thing as for stats, but without the stat info. */ |
342 | return update_ordered_entry (name, 0, 0, hook); |
343 | } |
344 | |
345 | /* Refresh DIR from the directory DIR_NAME in the filesystem FS. If |
346 | UPDATE_STATS is true, then directory stat information will also be |
347 | updated. If PRESERVE_ENTRY is non-0, that entry won't be deleted if it's |
348 | not in the directory after the refresh, but instead will have its NOENT |
349 | flag turned on. */ |
350 | static error_t |
351 | refresh_dir (struct ftpfs_dir *dir, int update_stats, time_t timestamp, |
352 | struct ftpfs_dir_entry *preserve_entry) |
353 | { |
354 | error_t err; |
355 | struct ftp_conn *conn; |
356 | struct dir_fetch_state dfs; |
357 | |
358 | if ((update_stats |
359 | ? dir->stat_timestamp + dir->fs->params.stat_timeout |
360 | : dir->name_timestamp + dir->fs->params.name_timeout) |
361 | >= timestamp) |
362 | /* We've already refreshed this directory recently. */ |
363 | return 0; |
364 | |
365 | err = ftpfs_get_ftp_conn (dir->fs, &conn); |
366 | if (err) |
367 | return err; |
368 | |
369 | /* Mark directory entries so we can GC them later using sweep. */ |
370 | mark (dir); |
371 | |
372 | if (update_stats) |
373 | /* We're doing a bulk stat now, so don't do another for a while. */ |
374 | reset_bulk_stat_info (dir); |
375 | |
376 | /* Info passed to update_ordered_entry. */ |
377 | dfs.dir = dir; |
378 | dfs.timestamp = timestamp; |
379 | dfs.prev_entry_next_p = &dir->ordered; |
380 | |
381 | /* Make sure `.' and `..' are always included (if the actual list also |
382 | includes `.' and `..', the ordered may be rearranged). */ |
383 | err = update_ordered_name (".", &dfs); |
384 | if (! err) |
385 | err = update_ordered_name ("..", &dfs); |
Value stored to 'err' is never read | |
386 | |
387 | /* Refetch the directory from the server. */ |
388 | if (update_stats) |
389 | /* Fetch both names and stat info. */ |
390 | err = ftp_conn_get_stats (conn, dir->rmt_path, 1, |
391 | update_ordered_entry, &dfs); |
392 | else |
393 | /* Just fetch names. */ |
394 | err = ftp_conn_get_names (conn, dir->rmt_path, update_ordered_name, &dfs); |
395 | |
396 | if (! err) |
397 | /* GC any directory entries that weren't seen this time. */ |
398 | { |
399 | dir->name_timestamp = timestamp; |
400 | if (update_stats) |
401 | dir->stat_timestamp = timestamp; |
402 | if (preserve_entry && !preserve_entry->valid) |
403 | { |
404 | preserve_entry->noent = 1; |
405 | preserve_entry->name_timestamp = timestamp; |
406 | } |
407 | sweep (dir); |
408 | } |
409 | |
410 | ftpfs_release_ftp_conn (dir->fs, conn); |
411 | |
412 | return err; |
413 | } |
414 | |
415 | /* Refresh DIR. */ |
416 | error_t |
417 | ftpfs_dir_refresh (struct ftpfs_dir *dir) |
418 | { |
419 | time_t timestamp = NOW({ struct timeval tv; maptime_read (ftpfs_maptime, &tv); tv .tv_sec; }); |
420 | return refresh_dir (dir, 0, timestamp, 0); |
421 | } |
422 | |
423 | /* State shared between ftpfs_dir_entry_refresh and update_old_entry. */ |
424 | struct refresh_entry_state |
425 | { |
426 | struct ftpfs_dir_entry *entry; |
427 | time_t timestamp; |
428 | }; |
429 | |
430 | /* Update the directory entry for NAME to reflect ST and SYMLINK_TARGET. |
431 | HOOK points to the state from ftpfs_dir_fetch_entry. */ |
432 | static error_t |
433 | update_old_entry (const char *name, const struct stat *st, |
434 | const char *symlink_target, void *hook) |
435 | { |
436 | struct refresh_entry_state *res = hook; |
437 | |
438 | if (strcmp (name, res->entry->name) != 0) |
439 | return EGRATUITOUS((0x10 << 26) | ((105) & 0x3fff)); |
440 | |
441 | update_entry (res->entry, st, symlink_target, res->timestamp); |
442 | |
443 | return 0; |
444 | } |
445 | |
446 | /* Refresh stat information for NODE. This may actually refresh the whole |
447 | directory if that is deemed desirable. NODE should be locked. */ |
448 | error_t |
449 | ftpfs_refresh_node (struct node *node) |
450 | { |
451 | struct netnode *nn = node->nn; |
452 | struct ftpfs_dir_entry *entry = nn->dir_entry; |
453 | |
454 | if (! entry) |
455 | /* This is a deleted node, don't attempt to do anything. */ |
456 | return 0; |
457 | else |
458 | { |
459 | error_t err = 0; |
460 | time_t timestamp = NOW({ struct timeval tv; maptime_read (ftpfs_maptime, &tv); tv .tv_sec; }); |
461 | struct ftpfs_dir *dir = entry->dir; |
462 | |
463 | pthread_mutex_lock (&dir->node->lock); |
464 | |
465 | if (! entry->self_p) |
466 | /* This is a deleted entry, just awaiting disposal; do so. */ |
467 | { |
468 | nn->dir_entry = 0; |
469 | free_entry (entry); |
470 | return 0; |
471 | } |
472 | else if ((entry->name_timestamp + dir->fs->params.name_timeout |
473 | >= timestamp) |
474 | && entry->noent) |
475 | err = ENOENT((0x10 << 26) | ((2) & 0x3fff)); |
476 | else if (entry->stat_timestamp + dir->fs->params.stat_timeout < timestamp) |
477 | { |
478 | /* Stat information needs updating. */ |
479 | if (need_bulk_stat (timestamp, dir)) |
480 | /* Refetch the whole directory from the server. */ |
481 | { |
482 | err = refresh_dir (entry->dir, 1, timestamp, entry); |
483 | if (!err && entry->noent) |
484 | err = ENOENT((0x10 << 26) | ((2) & 0x3fff)); |
485 | } |
486 | else if (*(entry->name)) |
487 | { |
488 | /* The root node is treated separately below. */ |
489 | struct ftp_conn *conn; |
490 | |
491 | err = ftpfs_get_ftp_conn (dir->fs, &conn); |
492 | |
493 | if (! err) |
494 | { |
495 | char *rmt_path; |
496 | |
497 | err = ftp_conn_append_name (conn, dir->rmt_path, entry->name, |
498 | &rmt_path); |
499 | if (! err) |
500 | { |
501 | struct refresh_entry_state res; |
502 | |
503 | res.entry = entry; |
504 | res.timestamp = timestamp; |
505 | |
506 | if (! err) |
507 | err = ftp_conn_get_stats (conn, rmt_path, 0, |
508 | update_old_entry, &res); |
509 | |
510 | free (rmt_path); |
511 | } |
512 | |
513 | ftpfs_release_ftp_conn (dir->fs, conn); |
514 | } |
515 | |
516 | if (err == ENOENT((0x10 << 26) | ((2) & 0x3fff))) |
517 | { |
518 | entry->noent = 1; /* A negative entry. */ |
519 | entry->name_timestamp = timestamp; |
520 | } |
521 | } |
522 | else |
523 | { |
524 | /* Refresh the root node with the old stat |
525 | information. */ |
526 | struct refresh_entry_state res; |
527 | res.entry = entry; |
528 | res.timestamp = timestamp; |
529 | err = update_old_entry (entry->name, |
530 | &netfs_root_node->nn_stat, |
531 | NULL((void*)0), &res); |
532 | } |
533 | } |
534 | |
535 | if ((entry->stat.st_mtim.tv_sec < node->nn_stat.st_mtim.tv_sec |
536 | || (entry->stat.st_mtim.tv_sec == node->nn_stat.st_mtim.tv_sec |
537 | && entry->stat.st_mtim.tv_nsec < node->nn_stat.st_mtim.tv_nsec) |
538 | || entry->stat.st_size != node->nn_stat.st_size) |
539 | && nn && nn->contents) |
540 | /* The file has changed. */ |
541 | ccache_invalidate (nn->contents); |
542 | |
543 | node->nn_stat = entry->stat; |
544 | node->nn_translated = S_ISLNK (entry->stat.st_mode)((((entry->stat.st_mode)) & 0170000) == (0120000)) ? S_IFLNK0120000 : 0; |
545 | if (!nn->dir && S_ISDIR (entry->stat.st_mode)((((entry->stat.st_mode)) & 0170000) == (0040000))) |
546 | ftpfs_dir_create (nn->fs, node, nn->rmt_path, &nn->dir); |
547 | |
548 | pthread_mutex_unlock (&dir->node->lock); |
549 | |
550 | ftpfs_cache_node (node); |
551 | |
552 | return err; |
553 | } |
554 | } |
555 | |
556 | /* Remove NODE from its entry (if the entry is still valid, it will remain |
557 | without a node). NODE should be locked. */ |
558 | error_t |
559 | ftpfs_detach_node (struct node *node) |
560 | { |
561 | struct netnode *nn = node->nn; |
562 | struct ftpfs_dir_entry *entry = nn->dir_entry; |
563 | |
564 | if (entry) |
565 | /* NODE is still attached to some entry, so detach it. */ |
566 | { |
567 | struct ftpfs_dir *dir = entry->dir; |
568 | |
569 | pthread_mutex_lock (&dir->node->lock); |
570 | |
571 | if (entry->self_p) |
572 | /* Just detach NODE from the still active entry. */ |
573 | entry->node = 0; |
574 | else |
575 | /* This is a deleted entry, just awaiting disposal; do so. */ |
576 | { |
577 | nn->dir_entry = 0; |
578 | free_entry (entry); |
579 | } |
580 | |
581 | if (--dir->num_live_entries == 0) |
582 | netfs_nput (dir->node); |
583 | else |
584 | pthread_mutex_unlock (&dir->node->lock); |
585 | } |
586 | |
587 | return 0; |
588 | } |
589 | |
590 | /* State shared between ftpfs_dir_lookup and update_new_entry. */ |
591 | struct new_entry_state |
592 | { |
593 | time_t timestamp; |
594 | struct ftpfs_dir *dir; |
595 | struct ftpfs_dir_entry *entry; |
596 | }; |
597 | |
598 | /* Update the directory entry for NAME to reflect ST and SYMLINK_TARGET. |
599 | HOOK->entry will be updated to reflect the new entry. */ |
600 | static error_t |
601 | update_new_entry (const char *name, const struct stat *st, |
602 | const char *symlink_target, void *hook) |
603 | { |
604 | struct ftpfs_dir_entry *e; |
605 | struct new_entry_state *nes = hook; |
606 | |
607 | e = lookup (nes->dir, name, 1); |
608 | if (! e) |
609 | return ENOMEM((0x10 << 26) | ((12) & 0x3fff)); |
610 | |
611 | update_entry (e, st, symlink_target, nes->timestamp); |
612 | nes->entry = e; |
613 | |
614 | return 0; |
615 | } |
616 | |
617 | /* Lookup NAME in DIR, returning its entry, or an error. DIR's node should |
618 | be locked, and will be unlocked after returning; *NODE will contain the |
619 | result node, locked, and with an additional reference, or 0 if an error |
620 | occurs. */ |
621 | error_t |
622 | ftpfs_dir_lookup (struct ftpfs_dir *dir, const char *name, |
623 | struct node **node) |
624 | { |
625 | struct ftp_conn *conn; |
626 | struct ftpfs_dir_entry *e; |
627 | error_t err = 0; |
628 | char *rmt_path = 0; |
629 | time_t timestamp = NOW({ struct timeval tv; maptime_read (ftpfs_maptime, &tv); tv .tv_sec; }); |
630 | |
631 | if (*name == '\0' || strcmp (name, ".") == 0) |
632 | /* Current directory -- just add an additional reference to DIR's node |
633 | and return it. */ |
634 | { |
635 | netfs_nref (dir->node); |
636 | *node = dir->node; |
637 | return 0; |
638 | } |
639 | else if (strcmp (name, "..") == 0) |
640 | /* Parent directory. */ |
641 | { |
642 | if (dir->node->nn->dir_entry) |
643 | { |
644 | *node = dir->node->nn->dir_entry->dir->node; |
645 | pthread_mutex_lock (&(*node)->lock); |
646 | netfs_nref (*node); |
647 | } |
648 | else |
649 | { |
650 | err = ENOENT((0x10 << 26) | ((2) & 0x3fff)); /* No .. */ |
651 | *node = 0; |
652 | } |
653 | |
654 | pthread_mutex_unlock (&dir->node->lock); |
655 | |
656 | return err; |
657 | } |
658 | |
659 | e = lookup (dir, name, 0); |
660 | if (!e || e->name_timestamp + dir->fs->params.name_timeout < timestamp) |
661 | /* Try to fetch info about NAME. */ |
662 | { |
663 | if (need_bulk_stat (timestamp, dir)) |
664 | /* Refetch the whole directory from the server. */ |
665 | { |
666 | err = refresh_dir (dir, 1, timestamp, e); |
667 | if (!err && !e) |
668 | e = lookup (dir, name, 0); |
669 | } |
670 | else |
671 | { |
672 | err = ftpfs_get_ftp_conn (dir->fs, &conn); |
673 | if (! err) |
674 | { |
675 | err = ftp_conn_append_name (conn, dir->rmt_path, name, |
676 | &rmt_path); |
677 | if (! err) |
678 | { |
679 | struct new_entry_state nes; |
680 | |
681 | nes.dir = dir; |
682 | nes.timestamp = timestamp; |
683 | nes.entry = NULL((void*)0); |
684 | |
685 | err = ftp_conn_get_stats (conn, rmt_path, 0, |
686 | update_new_entry, &nes); |
687 | if (! err) |
688 | e = nes.entry; |
689 | else if (err == ENOENT((0x10 << 26) | ((2) & 0x3fff))) |
690 | { |
691 | e = lookup (dir, name, 1); |
692 | if (! e) |
693 | err = ENOMEM((0x10 << 26) | ((12) & 0x3fff)); |
694 | else |
695 | { |
696 | e->noent = 1; /* A negative entry. */ |
697 | e->name_timestamp = timestamp; |
698 | } |
699 | } |
700 | } |
701 | |
702 | ftpfs_release_ftp_conn (dir->fs, conn); |
703 | } |
704 | } |
705 | } |
706 | |
707 | if (! err) |
708 | { |
709 | if (e && !e->noent) |
710 | /* We've got a dir entry, get a node for it. */ |
711 | { |
712 | /* If there's already a node, add a ref so that it doesn't go |
713 | away. */ |
714 | pthread_spin_lock (&netfs_node_refcnt_lock); |
715 | if (e->node) |
716 | e->node->references++; |
717 | pthread_spin_unlock (&netfs_node_refcnt_lock); |
718 | |
719 | if (! e->node) |
720 | /* No node; make one and install it into E. */ |
721 | { |
722 | if (! rmt_path) |
723 | /* We have to cons up the absolute path. We need the |
724 | connection just for the pathname frobbing functions. */ |
725 | { |
726 | err = ftpfs_get_ftp_conn (dir->fs, &conn); |
727 | if (! err) |
728 | { |
729 | err = ftp_conn_append_name (conn, dir->rmt_path, name, |
730 | &rmt_path); |
731 | ftpfs_release_ftp_conn (dir->fs, conn); |
732 | } |
733 | } |
734 | |
735 | if (! err) |
736 | { |
737 | err = ftpfs_create_node (e, rmt_path, &e->node); |
738 | |
739 | if (!err && dir->num_live_entries++ == 0) |
740 | /* Keep a reference to dir's node corresponding to |
741 | children. */ |
742 | { |
743 | pthread_spin_lock (&netfs_node_refcnt_lock); |
744 | dir->node->references++; |
745 | pthread_spin_unlock (&netfs_node_refcnt_lock); |
746 | } |
747 | } |
748 | } |
749 | |
750 | if (! err) |
751 | { |
752 | *node = e->node; |
753 | /* We have to unlock DIR's node before locking the child node |
754 | because the locking order is always child-parent. We know |
755 | the child node won't go away because we already hold the |
756 | additional reference to it. */ |
757 | pthread_mutex_unlock (&dir->node->lock); |
758 | pthread_mutex_lock (&e->node->lock); |
759 | } |
760 | } |
761 | else |
762 | err = ENOENT((0x10 << 26) | ((2) & 0x3fff)); |
763 | } |
764 | |
765 | if (err) |
766 | { |
767 | *node = 0; |
768 | pthread_mutex_unlock (&dir->node->lock); |
769 | } |
770 | |
771 | if (rmt_path) |
772 | free (rmt_path); |
773 | |
774 | return err; |
775 | } |
776 | |
777 | /* Lookup the null name in DIR, and return a node for it in NODE. Unlike |
778 | ftpfs_dir_lookup, this won't attempt to validate the existence of the |
779 | entry (to avoid opening a new connection if possible) -- that will happen |
780 | the first time the entry is refreshed. Also unlink ftpfs_dir_lookup, this |
781 | function doesn't expect DIR to be locked, and won't return *NODE locked. |
782 | This function is only used for bootstrapping the root node. */ |
783 | error_t |
784 | ftpfs_dir_null_lookup (struct ftpfs_dir *dir, struct node **node) |
785 | { |
786 | struct ftpfs_dir_entry *e; |
787 | error_t err = 0; |
788 | |
789 | e = lookup (dir, "", 1); |
790 | if (! e) |
791 | return ENOMEM((0x10 << 26) | ((12) & 0x3fff)); |
792 | |
793 | if (! e->noent) |
794 | /* We've got a dir entry, get a node for it. */ |
795 | { |
796 | /* If there's already a node, add a ref so that it doesn't go away. */ |
797 | pthread_spin_lock (&netfs_node_refcnt_lock); |
798 | if (e->node) |
799 | e->node->references++; |
800 | pthread_spin_unlock (&netfs_node_refcnt_lock); |
801 | |
802 | if (! e->node) |
803 | /* No node; make one and install it into E. */ |
804 | { |
805 | err = ftpfs_create_node (e, dir->rmt_path, &e->node); |
806 | |
807 | if (!err && dir->num_live_entries++ == 0) |
808 | /* Keep a reference to dir's node corresponding to children. */ |
809 | { |
810 | pthread_spin_lock (&netfs_node_refcnt_lock); |
811 | dir->node->references++; |
812 | pthread_spin_unlock (&netfs_node_refcnt_lock); |
813 | } |
814 | } |
815 | |
816 | if (! err) |
817 | *node = e->node; |
818 | } |
819 | else |
820 | err = ENOENT((0x10 << 26) | ((2) & 0x3fff)); |
821 | |
822 | return err; |
823 | } |
824 | |
825 | /* Size of initial htable for a new directory. */ |
826 | #define INIT_HTABLE_LEN5 5 |
827 | |
828 | /* Return in DIR a new ftpfs directory, in the filesystem FS, with node NODE |
829 | and remote path RMT_PATH. RMT_PATH is *not copied*, so it shouldn't ever |
830 | change while this directory is active. */ |
831 | error_t |
832 | ftpfs_dir_create (struct ftpfs *fs, struct node *node, const char *rmt_path, |
833 | struct ftpfs_dir **dir) |
834 | { |
835 | struct ftpfs_dir *new = malloc (sizeof (struct ftpfs_dir)); |
836 | struct ftpfs_dir_entry **htable |
837 | = calloc (INIT_HTABLE_LEN5, sizeof (struct ftpfs_dir_entry *)); |
838 | |
839 | if (!new || !htable) |
840 | { |
841 | if (new) |
842 | free (new); |
843 | if (htable) |
844 | free (htable); |
845 | return ENOMEM((0x10 << 26) | ((12) & 0x3fff)); |
846 | } |
847 | |
848 | /* Hold a reference to the new dir's node. */ |
849 | pthread_spin_lock (&netfs_node_refcnt_lock); |
850 | node->references++; |
851 | pthread_spin_unlock (&netfs_node_refcnt_lock); |
852 | |
853 | new->num_entries = 0; |
854 | new->num_live_entries = 0; |
855 | new->htable_len = INIT_HTABLE_LEN5; |
856 | new->htable = htable; |
857 | new->ordered = 0; |
858 | new->rmt_path = rmt_path; |
859 | new->fs = fs; |
860 | new->node = node; |
861 | new->stat_timestamp = 0; |
862 | new->name_timestamp = 0; |
863 | new->bulk_stat_base_stamp = 0; |
864 | new->bulk_stat_count_first_half = 0; |
865 | new->bulk_stat_count_second_half = 0; |
866 | |
867 | *dir = new; |
868 | |
869 | return 0; |
870 | } |
871 | |
872 | void |
873 | ftpfs_dir_free (struct ftpfs_dir *dir) |
874 | { |
875 | /* Free all entries. */ |
876 | mark (dir); |
877 | sweep (dir); |
878 | |
879 | if (dir->htable) |
880 | free (dir->htable); |
881 | |
882 | netfs_nrele (dir->node); |
883 | |
884 | free (dir); |
885 | } |