r12221: Fix error code paths that can potentially leave a dangling lock.
[samba.git] / source3 / locking / locking.c
1 /* 
2    Unix SMB/CIFS implementation.
3    Locking functions
4    Copyright (C) Andrew Tridgell 1992-2000
5    Copyright (C) Jeremy Allison 1992-2000
6    Copyright (C) Volker Lendecke 2005
7    
8    This program is free software; you can redistribute it and/or modify
9    it under the terms of the GNU General Public License as published by
10    the Free Software Foundation; either version 2 of the License, or
11    (at your option) any later version.
12    
13    This program is distributed in the hope that it will be useful,
14    but WITHOUT ANY WARRANTY; without even the implied warranty of
15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16    GNU General Public License for more details.
17    
18    You should have received a copy of the GNU General Public License
19    along with this program; if not, write to the Free Software
20    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21
22    Revision History:
23
24    12 aug 96: Erik.Devriendt@te6.siemens.be
25    added support for shared memory implementation of share mode locking
26
27    May 1997. Jeremy Allison (jallison@whistle.com). Modified share mode
28    locking to deal with multiple share modes per open file.
29
30    September 1997. Jeremy Allison (jallison@whistle.com). Added oplock
31    support.
32
33    rewrtten completely to use new tdb code. Tridge, Dec '99
34
35    Added POSIX locking support. Jeremy Allison (jeremy@valinux.com), Apr. 2000.
36 */
37
38 #include "includes.h"
39 uint16 global_smbpid;
40
41 #undef DBGC_CLASS
42 #define DBGC_CLASS DBGC_LOCKING
43
44 /* the locking database handle */
45 static TDB_CONTEXT *tdb;
46
47 struct locking_data {
48         union {
49                 struct {
50                         int num_share_mode_entries;
51                         BOOL delete_on_close;
52                 } s;
53                 struct share_mode_entry dummy; /* Needed for alignment. */
54         } u;
55         /* the following two entries are implicit
56            struct share_mode_entry modes[num_share_mode_entries];
57            char file_name[];
58         */
59 };
60
61 /****************************************************************************
62  Debugging aid :-).
63 ****************************************************************************/
64
65 static const char *lock_type_name(enum brl_type lock_type)
66 {
67         return (lock_type == READ_LOCK) ? "READ" : "WRITE";
68 }
69
70 /****************************************************************************
71  Utility function called to see if a file region is locked.
72 ****************************************************************************/
73
74 BOOL is_locked(files_struct *fsp,connection_struct *conn,
75                SMB_BIG_UINT count,SMB_BIG_UINT offset, 
76                enum brl_type lock_type)
77 {
78         int snum = SNUM(conn);
79         int strict_locking = lp_strict_locking(snum);
80         BOOL ret;
81         
82         if (count == 0)
83                 return(False);
84
85         if (!lp_locking(snum) || !strict_locking)
86                 return(False);
87
88         if (strict_locking == Auto) {
89                 if  (EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type) && (lock_type == READ_LOCK || lock_type == WRITE_LOCK)) {
90                         DEBUG(10,("is_locked: optimisation - exclusive oplock on file %s\n", fsp->fsp_name ));
91                         ret = 0;
92                 } else if ((fsp->oplock_type == LEVEL_II_OPLOCK) &&
93                            (lock_type == READ_LOCK)) {
94                         DEBUG(10,("is_locked: optimisation - level II oplock on file %s\n", fsp->fsp_name ));
95                         ret = 0;
96                 } else {
97                         ret = !brl_locktest(fsp->dev, fsp->inode, fsp->fnum,
98                                      global_smbpid, procid_self(), conn->cnum, 
99                                      offset, count, lock_type);
100                 }
101         } else {
102                 ret = !brl_locktest(fsp->dev, fsp->inode, fsp->fnum,
103                                 global_smbpid, procid_self(), conn->cnum,
104                                 offset, count, lock_type);
105         }
106
107         DEBUG(10,("is_locked: brl start=%.0f len=%.0f %s for file %s\n",
108                         (double)offset, (double)count, ret ? "locked" : "unlocked",
109                         fsp->fsp_name ));
110
111         /*
112          * There is no lock held by an SMB daemon, check to
113          * see if there is a POSIX lock from a UNIX or NFS process.
114          */
115
116         if(!ret && lp_posix_locking(snum)) {
117                 ret = is_posix_locked(fsp, offset, count, lock_type);
118
119                 DEBUG(10,("is_locked: posix start=%.0f len=%.0f %s for file %s\n",
120                                 (double)offset, (double)count, ret ? "locked" : "unlocked",
121                                 fsp->fsp_name ));
122         }
123
124         return ret;
125 }
126
127 /****************************************************************************
128  Utility function called by locking requests.
129 ****************************************************************************/
130
131 static NTSTATUS do_lock(files_struct *fsp,connection_struct *conn, uint16 lock_pid,
132                  SMB_BIG_UINT count,SMB_BIG_UINT offset,enum brl_type lock_type, BOOL *my_lock_ctx)
133 {
134         NTSTATUS status = NT_STATUS_LOCK_NOT_GRANTED;
135
136         if (!lp_locking(SNUM(conn)))
137                 return NT_STATUS_OK;
138
139         /* NOTE! 0 byte long ranges ARE allowed and should be stored  */
140
141         DEBUG(10,("do_lock: lock type %s start=%.0f len=%.0f requested for file %s\n",
142                   lock_type_name(lock_type), (double)offset, (double)count, fsp->fsp_name ));
143
144         if (OPEN_FSP(fsp) && fsp->can_lock && (fsp->conn == conn)) {
145                 status = brl_lock(fsp->dev, fsp->inode, fsp->fnum,
146                                   lock_pid, procid_self(), conn->cnum, 
147                                   offset, count, 
148                                   lock_type, my_lock_ctx);
149
150                 if (NT_STATUS_IS_OK(status) && lp_posix_locking(SNUM(conn))) {
151
152                         /*
153                          * Try and get a POSIX lock on this range.
154                          * Note that this is ok if it is a read lock
155                          * overlapping on a different fd. JRA.
156                          */
157
158                         if (!set_posix_lock(fsp, offset, count, lock_type)) {
159                                 if (errno == EACCES || errno == EAGAIN)
160                                         status = NT_STATUS_FILE_LOCK_CONFLICT;
161                                 else
162                                         status = map_nt_error_from_unix(errno);
163
164                                 /*
165                                  * We failed to map - we must now remove the brl
166                                  * lock entry.
167                                  */
168                                 (void)brl_unlock(fsp->dev, fsp->inode, fsp->fnum,
169                                                                 lock_pid, procid_self(), conn->cnum, 
170                                                                 offset, count, False,
171                                                                 NULL, NULL);
172                         }
173                 }
174         }
175
176         return status;
177 }
178
179 /****************************************************************************
180  Utility function called by locking requests. This is *DISGUSTING*. It also
181  appears to be "What Windows Does" (tm). Andrew, ever wonder why Windows 2000
182  is so slow on the locking tests...... ? This is the reason. Much though I hate
183  it, we need this. JRA.
184 ****************************************************************************/
185
186 NTSTATUS do_lock_spin(files_struct *fsp,connection_struct *conn, uint16 lock_pid,
187                  SMB_BIG_UINT count,SMB_BIG_UINT offset,enum brl_type lock_type, BOOL *my_lock_ctx)
188 {
189         int j, maxj = lp_lock_spin_count();
190         int sleeptime = lp_lock_sleep_time();
191         NTSTATUS status, ret;
192
193         if (maxj <= 0)
194                 maxj = 1;
195
196         ret = NT_STATUS_OK; /* to keep dumb compilers happy */
197
198         for (j = 0; j < maxj; j++) {
199                 status = do_lock(fsp, conn, lock_pid, count, offset, lock_type, my_lock_ctx);
200                 if (!NT_STATUS_EQUAL(status, NT_STATUS_LOCK_NOT_GRANTED) &&
201                     !NT_STATUS_EQUAL(status, NT_STATUS_FILE_LOCK_CONFLICT)) {
202                         return status;
203                 }
204                 /* if we do fail then return the first error code we got */
205                 if (j == 0) {
206                         ret = status;
207                         /* Don't spin if we blocked ourselves. */
208                         if (*my_lock_ctx)
209                                 return ret;
210                 }
211                 if (sleeptime)
212                         sys_usleep(sleeptime);
213         }
214         return ret;
215 }
216
217 /* Struct passed to brl_unlock. */
218 struct posix_unlock_data_struct {
219         files_struct *fsp;
220         SMB_BIG_UINT offset;
221         SMB_BIG_UINT count;
222 };
223
224 /****************************************************************************
225  Function passed to brl_unlock to allow POSIX unlock to be done first.
226 ****************************************************************************/
227
228 static void posix_unlock(void *pre_data)
229 {
230         struct posix_unlock_data_struct *pdata = (struct posix_unlock_data_struct *)pre_data;
231
232         if (lp_posix_locking(SNUM(pdata->fsp->conn)))
233                 release_posix_lock(pdata->fsp, pdata->offset, pdata->count);
234 }
235
236 /****************************************************************************
237  Utility function called by unlocking requests.
238 ****************************************************************************/
239
240 NTSTATUS do_unlock(files_struct *fsp,connection_struct *conn, uint16 lock_pid,
241                    SMB_BIG_UINT count,SMB_BIG_UINT offset)
242 {
243         BOOL ok = False;
244         struct posix_unlock_data_struct posix_data;
245         
246         if (!lp_locking(SNUM(conn)))
247                 return NT_STATUS_OK;
248         
249         if (!OPEN_FSP(fsp) || !fsp->can_lock || (fsp->conn != conn)) {
250                 return NT_STATUS_INVALID_HANDLE;
251         }
252         
253         DEBUG(10,("do_unlock: unlock start=%.0f len=%.0f requested for file %s\n",
254                   (double)offset, (double)count, fsp->fsp_name ));
255
256         /*
257          * Remove the existing lock record from the tdb lockdb
258          * before looking at POSIX locks. If this record doesn't
259          * match then don't bother looking to remove POSIX locks.
260          */
261
262         posix_data.fsp = fsp;
263         posix_data.offset = offset;
264         posix_data.count = count;
265
266         ok = brl_unlock(fsp->dev, fsp->inode, fsp->fnum,
267                         lock_pid, procid_self(), conn->cnum, offset, count,
268                         False, posix_unlock, (void *)&posix_data);
269    
270         if (!ok) {
271                 DEBUG(10,("do_unlock: returning ERRlock.\n" ));
272                 return NT_STATUS_RANGE_NOT_LOCKED;
273         }
274         return NT_STATUS_OK;
275 }
276
277 /****************************************************************************
278  Remove any locks on this fd. Called from file_close().
279 ****************************************************************************/
280
281 void locking_close_file(files_struct *fsp)
282 {
283         struct process_id pid = procid_self();
284
285         if (!lp_locking(SNUM(fsp->conn)))
286                 return;
287
288         /*
289          * Just release all the brl locks, no need to release individually.
290          */
291
292         brl_close(fsp->dev, fsp->inode, pid, fsp->conn->cnum, fsp->fnum);
293
294         if(lp_posix_locking(SNUM(fsp->conn))) {
295
296                 /* 
297                  * Release all the POSIX locks.
298                  */
299                 posix_locking_close_file(fsp);
300
301         }
302 }
303
304 /****************************************************************************
305  Initialise the locking functions.
306 ****************************************************************************/
307
308 static int open_read_only;
309
310 BOOL locking_init(int read_only)
311 {
312         brl_init(read_only);
313
314         if (tdb)
315                 return True;
316
317         tdb = tdb_open_log(lock_path("locking.tdb"), 
318                         SMB_OPEN_DATABASE_TDB_HASH_SIZE, TDB_DEFAULT|(read_only?0x0:TDB_CLEAR_IF_FIRST), 
319                         read_only?O_RDONLY:O_RDWR|O_CREAT,
320                         0644);
321
322         if (!tdb) {
323                 DEBUG(0,("ERROR: Failed to initialise locking database\n"));
324                 return False;
325         }
326
327         if (!posix_locking_init(read_only))
328                 return False;
329
330         open_read_only = read_only;
331
332         return True;
333 }
334
335 /*******************************************************************
336  Deinitialize the share_mode management.
337 ******************************************************************/
338
339 BOOL locking_end(void)
340 {
341         BOOL ret = True;
342
343         brl_shutdown(open_read_only);
344         if (tdb) {
345                 if (tdb_close(tdb) != 0)
346                         ret = False;
347         }
348
349         return ret;
350 }
351
352 /*******************************************************************
353  Form a static locking key for a dev/inode pair.
354 ******************************************************************/
355
356 /* key and data records in the tdb locking database */
357 struct locking_key {
358         SMB_DEV_T dev;
359         SMB_INO_T ino;
360 };
361
362 /*******************************************************************
363  Form a static locking key for a dev/inode pair.
364 ******************************************************************/
365
366 static TDB_DATA locking_key(SMB_DEV_T dev, SMB_INO_T inode)
367 {
368         static struct locking_key key;
369         TDB_DATA kbuf;
370
371         memset(&key, '\0', sizeof(key));
372         key.dev = dev;
373         key.ino = inode;
374         kbuf.dptr = (char *)&key;
375         kbuf.dsize = sizeof(key);
376         return kbuf;
377 }
378
379 /*******************************************************************
380  Print out a share mode.
381 ********************************************************************/
382
383 char *share_mode_str(int num, struct share_mode_entry *e)
384 {
385         static pstring share_str;
386
387         slprintf(share_str, sizeof(share_str)-1, "share_mode_entry[%d]: "
388                  "pid = %s, share_access = 0x%x, private_options = 0x%x, "
389                  "access_mask = 0x%x, mid = 0x%x, type= 0x%x, file_id = %lu, "
390                  "dev = 0x%x, inode = %.0f",
391                  num, procid_str_static(&e->pid),
392                  e->share_access, e->private_options,
393                  e->access_mask, e->op_mid, e->op_type, e->share_file_id,
394                  (unsigned int)e->dev, (double)e->inode );
395
396         return share_str;
397 }
398
399 /*******************************************************************
400  Print out a share mode table.
401 ********************************************************************/
402
403 static void print_share_mode_table(struct locking_data *data)
404 {
405         int num_share_modes = data->u.s.num_share_mode_entries;
406         struct share_mode_entry *shares =
407                 (struct share_mode_entry *)(data + 1);
408         int i;
409
410         for (i = 0; i < num_share_modes; i++) {
411                 struct share_mode_entry *entry_p = &shares[i];
412                 DEBUG(10,("print_share_mode_table: %s\n",
413                           share_mode_str(i, entry_p)));
414         }
415 }
416
417 /*******************************************************************
418  Get all share mode entries for a dev/inode pair.
419 ********************************************************************/
420
421 static BOOL parse_share_modes(TDB_DATA dbuf, struct share_mode_lock *lck)
422 {
423         struct locking_data *data;
424         int i;
425
426         if (dbuf.dsize < sizeof(struct locking_data)) {
427                 DEBUG(0, ("parse_share_modes: buffer too short\n"));
428                 return False;
429         }
430
431         data = (struct locking_data *)dbuf.dptr;
432
433         lck->delete_on_close = data->u.s.delete_on_close;
434         lck->num_share_modes = data->u.s.num_share_mode_entries;
435
436         DEBUG(10, ("parse_share_modes: delete_on_close: %d, "
437                    "num_share_modes: %d\n", lck->delete_on_close,
438                    lck->num_share_modes));
439
440         if ((lck->num_share_modes < 0) || (lck->num_share_modes > 1000000)) {
441                 DEBUG(0, ("invalid number of share modes: %d\n",
442                           lck->num_share_modes));
443                 return False;
444         }
445
446         lck->share_modes = NULL;
447
448         if (lck->num_share_modes != 0) {
449
450                 if (dbuf.dsize < (sizeof(struct locking_data) +
451                                   (lck->num_share_modes *
452                                    sizeof(struct share_mode_entry)))) {
453                         DEBUG(0, ("parse_share_modes: buffer too short\n"));
454                         return False;
455                 }
456                                   
457                 lck->share_modes = talloc_memdup(lck, dbuf.dptr+sizeof(*data),
458                                                  lck->num_share_modes *
459                                                  sizeof(struct share_mode_entry));
460
461                 if (lck->share_modes == NULL) {
462                         DEBUG(0, ("talloc failed\n"));
463                         return False;
464                 }
465         }
466
467         /* Save off the associated service path and filename. */
468         lck->servicepath = talloc_strdup(lck, dbuf.dptr + sizeof(*data) +
469                                       (lck->num_share_modes *
470                                       sizeof(struct share_mode_entry)));
471
472         lck->filename = talloc_strdup(lck, dbuf.dptr + sizeof(*data) +
473                                       (lck->num_share_modes *
474                                       sizeof(struct share_mode_entry)) +
475                                       strlen(lck->servicepath) + 1 );
476
477         /*
478          * Ensure that each entry has a real process attached.
479          */
480
481         for (i = 0; i < lck->num_share_modes; i++) {
482                 struct share_mode_entry *entry_p = &lck->share_modes[i];
483                 DEBUG(10,("parse_share_modes: %s\n",
484                           share_mode_str(i, entry_p) ));
485                 if (!process_exists(entry_p->pid)) {
486                         DEBUG(10,("parse_share_modes: deleted %s\n",
487                                   share_mode_str(i, entry_p) ));
488                         entry_p->op_type = UNUSED_SHARE_MODE_ENTRY;
489                         lck->modified = True;
490                 }
491         }
492
493         return True;
494 }
495
496 static TDB_DATA unparse_share_modes(struct share_mode_lock *lck)
497 {
498         TDB_DATA result;
499         int num_valid = 0;
500         int i;
501         struct locking_data *data;
502         ssize_t offset;
503         ssize_t sp_len;
504
505         result.dptr = NULL;
506         result.dsize = 0;
507
508         for (i=0; i<lck->num_share_modes; i++) {
509                 if (!is_unused_share_mode_entry(&lck->share_modes[i])) {
510                         num_valid += 1;
511                 }
512         }
513
514         if (num_valid == 0) {
515                 return result;
516         }
517
518         sp_len = strlen(lck->servicepath);
519
520         result.dsize = sizeof(*data) +
521                 lck->num_share_modes * sizeof(struct share_mode_entry) +
522                 sp_len + 1 +
523                 strlen(lck->filename) + 1;
524         result.dptr = talloc_size(lck, result.dsize);
525
526         if (result.dptr == NULL) {
527                 smb_panic("talloc failed\n");
528         }
529
530         data = (struct locking_data *)result.dptr;
531         ZERO_STRUCTP(data);
532         data->u.s.num_share_mode_entries = lck->num_share_modes;
533         data->u.s.delete_on_close = lck->delete_on_close;
534         DEBUG(10, ("unparse_share_modes: del: %d, num: %d\n",
535                    data->u.s.delete_on_close,
536                    data->u.s.num_share_mode_entries));
537         memcpy(result.dptr + sizeof(*data), lck->share_modes,
538                sizeof(struct share_mode_entry)*lck->num_share_modes);
539         offset = sizeof(*data) +
540                 sizeof(struct share_mode_entry)*lck->num_share_modes;
541         safe_strcpy(result.dptr + offset, lck->servicepath,
542                     result.dsize - offset - 1);
543         offset += sp_len + 1;
544         safe_strcpy(result.dptr + offset, lck->filename,
545                     result.dsize - offset - 1);
546         print_share_mode_table(data);
547         return result;
548 }
549
550 static int share_mode_lock_destructor(void *p)
551 {
552         struct share_mode_lock *lck =
553                 talloc_get_type_abort(p, struct share_mode_lock);
554         TDB_DATA key = locking_key(lck->dev, lck->ino);
555         TDB_DATA data;
556
557         if (!lck->modified) {
558                 goto done;
559         }
560
561         data = unparse_share_modes(lck);
562
563         if (data.dptr == NULL) {
564                 if (!lck->fresh) {
565                         /* There has been an entry before, delete it */
566                         if (tdb_delete(tdb, key) == -1) {
567                                 smb_panic("Could not delete share entry\n");
568                         }
569                 }
570                 goto done;
571         }
572
573         if (tdb_store(tdb, key, data, TDB_REPLACE) == -1) {
574                 smb_panic("Could not store share mode entry\n");
575         }
576
577  done:
578         tdb_chainunlock(tdb, key);
579
580         return 0;
581 }
582
583 struct share_mode_lock *get_share_mode_lock(TALLOC_CTX *mem_ctx,
584                                                 SMB_DEV_T dev, SMB_INO_T ino,
585                                                 const char *servicepath,
586                                                 const char *fname)
587 {
588         struct share_mode_lock *lck;
589         TDB_DATA key = locking_key(dev, ino);
590         TDB_DATA data;
591
592         lck = TALLOC_P(mem_ctx, struct share_mode_lock);
593         if (lck == NULL) {
594                 DEBUG(0, ("talloc failed\n"));
595                 return NULL;
596         }
597
598         /* Ensure we set every field here as the destructor must be
599            valid even if parse_share_modes fails. */
600
601         lck->servicepath = NULL;
602         lck->filename = NULL;
603         lck->dev = dev;
604         lck->ino = ino;
605         lck->num_share_modes = 0;
606         lck->share_modes = NULL;
607         lck->delete_on_close = False;
608         lck->modified = False;
609         lck->fresh = False;
610
611         if (tdb_chainlock(tdb, key) != 0) {
612                 DEBUG(3, ("Could not lock share entry\n"));
613                 talloc_free(lck);
614                 return NULL;
615         }
616
617         /* We must set the destructor immediately after the chainlock
618            ensure the lock is cleaned up on any of the error return
619            paths below. */
620
621         talloc_set_destructor(lck, share_mode_lock_destructor);
622
623         data = tdb_fetch(tdb, key);
624         lck->fresh = (data.dptr == NULL);
625
626         if (lck->fresh) {
627
628                 if (fname == NULL || servicepath == NULL) {
629                         DEBUG(0, ("New file, but no filename or servicepath supplied\n"));
630                         talloc_free(lck);
631                         return NULL;
632                 }
633                 lck->filename = talloc_strdup(lck, fname);
634                 lck->servicepath = talloc_strdup(lck, servicepath);
635                 if (lck->filename == NULL || lck->servicepath == NULL) {
636                         DEBUG(0, ("talloc failed\n"));
637                         talloc_free(lck);
638                         return NULL;
639                 }
640         } else {
641                 if (!parse_share_modes(data, lck)) {
642                         DEBUG(0, ("Could not parse share modes\n"));
643                         talloc_free(lck);
644                         SAFE_FREE(data.dptr);
645                         return NULL;
646                 }
647         }
648
649         SAFE_FREE(data.dptr);
650
651         return lck;
652 }
653
654 /*******************************************************************
655  Sets the service name and filename for rename.
656  At this point we emit "file renamed" messages to all
657  process id's that have this file open.
658  Based on an initial code idea from SATOH Fumiyasu <fumiya@samba.gr.jp>
659 ********************************************************************/
660
661 BOOL rename_share_filename(struct share_mode_lock *lck,
662                         const char *servicepath,
663                         const char *newname)
664 {
665         struct file_renamed_message *frm = NULL;
666         size_t sp_len;
667         size_t fn_len;
668         size_t msg_len;
669         int i;
670
671         DEBUG(10, ("rename_share_filename: servicepath %s newname %s\n",
672                 servicepath, newname));
673
674         /*
675          * rename_internal_fsp() and rename_internals() add './' to
676          * head of newname if newname does not contain a '/'.
677          */
678         while (newname[0] && newname[1] && newname[0] == '.' && newname[1] == '/') {
679                 newname += 2;
680         }
681
682         lck->servicepath = talloc_strdup(lck, servicepath);
683         lck->filename = talloc_strdup(lck, newname);
684         if (lck->filename == NULL || lck->servicepath == NULL) {
685                 DEBUG(0, ("rename_share_filename: talloc failed\n"));
686                 return False;
687         }
688         lck->modified = True;
689
690         sp_len = strlen(lck->servicepath);
691         fn_len = strlen(lck->filename);
692
693         msg_len = sizeof(*frm) + sp_len + 1 + fn_len + 1;
694
695         /* Set up the name changed message. */
696         frm = TALLOC(lck, msg_len);
697         if (!frm) {
698                 return False;
699         }
700         frm->dev = lck->dev;
701         frm->inode = lck->ino;
702
703         DEBUG(10,("rename_share_filename: msg_len = %d\n", msg_len ));
704
705         safe_strcpy(&frm->names[0], lck->servicepath, sp_len);
706         safe_strcpy(&frm->names[sp_len + 1], lck->filename, fn_len);
707
708         /* Send the messages. */
709         for (i=0; i<lck->num_share_modes; i++) {
710                 struct share_mode_entry *se = &lck->share_modes[i];
711                 if (!is_valid_share_mode_entry(se)) {
712                         continue;
713                 }
714                 /* But not to ourselves... */
715                 if (procid_is_me(&se->pid)) {
716                         continue;
717                 }
718
719                 DEBUG(10,("rename_share_filename: sending rename message to pid %u "
720                         "dev %x, inode  %.0f sharepath %s newname %s\n",
721                         (unsigned int)procid_to_pid(&se->pid),
722                         (unsigned int)frm->dev, (double)frm->inode,
723                         lck->servicepath, lck->filename ));
724
725                 message_send_pid(se->pid, MSG_SMB_FILE_RENAME,
726                                 frm, msg_len, True);
727         }
728
729         return True;
730 }
731
732 BOOL get_delete_on_close_flag(SMB_DEV_T dev, SMB_INO_T inode)
733 {
734         BOOL result;
735         struct share_mode_lock *lck = get_share_mode_lock(NULL, dev, inode, NULL, NULL);
736         if (!lck) {
737                 return False;
738         }
739         result = lck->delete_on_close;
740         talloc_free(lck);
741         return result;
742 }
743
744 BOOL is_valid_share_mode_entry(const struct share_mode_entry *e)
745 {
746         int num_props = 0;
747
748         num_props += ((e->op_type == NO_OPLOCK) ? 1 : 0);
749         num_props += (EXCLUSIVE_OPLOCK_TYPE(e->op_type) ? 1 : 0);
750         num_props += (LEVEL_II_OPLOCK_TYPE(e->op_type) ? 1 : 0);
751
752         SMB_ASSERT(num_props <= 1);
753         return (num_props != 0);
754 }
755
756 BOOL is_deferred_open_entry(const struct share_mode_entry *e)
757 {
758         return (e->op_type == DEFERRED_OPEN_ENTRY);
759 }
760
761 BOOL is_unused_share_mode_entry(const struct share_mode_entry *e)
762 {
763         return (e->op_type == UNUSED_SHARE_MODE_ENTRY);
764 }
765
766 /*******************************************************************
767  Fill a share mode entry.
768 ********************************************************************/
769
770 static void fill_share_mode_entry(struct share_mode_entry *e,
771                                   files_struct *fsp,
772                                   uint16 mid, uint16 op_type)
773 {
774         ZERO_STRUCTP(e);
775         e->pid = procid_self();
776         e->share_access = fsp->share_access;
777         e->private_options = fsp->fh->private_options;
778         e->access_mask = fsp->access_mask;
779         e->op_mid = mid;
780         e->op_type = op_type;
781         e->time.tv_sec = fsp->open_time.tv_sec;
782         e->time.tv_usec = fsp->open_time.tv_usec;
783         e->share_file_id = fsp->file_id;
784         e->dev = fsp->dev;
785         e->inode = fsp->inode;
786 }
787
788 static void fill_deferred_open_entry(struct share_mode_entry *e,
789                                      const struct timeval request_time,
790                                      SMB_DEV_T dev, SMB_INO_T ino, uint16 mid)
791 {
792         ZERO_STRUCTP(e);
793         e->pid = procid_self();
794         e->op_mid = mid;
795         e->op_type = DEFERRED_OPEN_ENTRY;
796         e->time.tv_sec = request_time.tv_sec;
797         e->time.tv_usec = request_time.tv_usec;
798         e->dev = dev;
799         e->inode = ino;
800 }
801
802 static void add_share_mode_entry(struct share_mode_lock *lck,
803                                  const struct share_mode_entry *entry)
804 {
805         int i;
806
807         for (i=0; i<lck->num_share_modes; i++) {
808                 struct share_mode_entry *e = &lck->share_modes[i];
809                 if (is_unused_share_mode_entry(e)) {
810                         *e = *entry;
811                         break;
812                 }
813         }
814
815         if (i == lck->num_share_modes) {
816                 /* No unused entry found */
817                 ADD_TO_ARRAY(lck, struct share_mode_entry, *entry,
818                              &lck->share_modes, &lck->num_share_modes);
819         }
820         lck->modified = True;
821 }
822
823 void set_share_mode(struct share_mode_lock *lck, files_struct *fsp,
824                     uint16 mid, uint16 op_type)
825 {
826         struct share_mode_entry entry;
827         fill_share_mode_entry(&entry, fsp, mid, op_type);
828         add_share_mode_entry(lck, &entry);
829 }
830
831 void add_deferred_open(struct share_mode_lock *lck, uint16 mid,
832                        struct timeval request_time,
833                        SMB_DEV_T dev, SMB_INO_T ino)
834 {
835         struct share_mode_entry entry;
836         fill_deferred_open_entry(&entry, request_time, dev, ino, mid);
837         add_share_mode_entry(lck, &entry);
838 }
839
840 /*******************************************************************
841  Check if two share mode entries are identical, ignoring oplock 
842  and mid info and desired_access.
843 ********************************************************************/
844
845 static BOOL share_modes_identical(struct share_mode_entry *e1,
846                                   struct share_mode_entry *e2)
847 {
848 #if 1 /* JRA PARANOIA TEST - REMOVE LATER */
849         if (procid_equal(&e1->pid, &e2->pid) &&
850             e1->share_file_id == e2->share_file_id &&
851             e1->dev == e2->dev &&
852             e1->inode == e2->inode &&
853             (e1->share_access) != (e2->share_access)) {
854                 DEBUG(0,("PANIC: share_modes_identical: share_mode "
855                          "mismatch (e1 = 0x%x, e2 = 0x%x). Logic error.\n",
856                          (unsigned int)e1->share_access,
857                          (unsigned int)e2->share_access ));
858                 smb_panic("PANIC: share_modes_identical logic error.\n");
859         }
860 #endif
861
862         return (procid_equal(&e1->pid, &e2->pid) &&
863                 (e1->share_access) == (e2->share_access) &&
864                 e1->dev == e2->dev &&
865                 e1->inode == e2->inode &&
866                 e1->share_file_id == e2->share_file_id );
867 }
868
869 static BOOL deferred_open_identical(struct share_mode_entry *e1,
870                                     struct share_mode_entry *e2)
871 {
872         return (procid_equal(&e1->pid, &e2->pid) &&
873                 (e1->op_mid == e2->op_mid) &&
874                 (e1->dev == e2->dev) &&
875                 (e1->inode == e2->inode));
876 }
877
878 static struct share_mode_entry *find_share_mode_entry(struct share_mode_lock *lck,
879                                                       struct share_mode_entry *entry)
880 {
881         int i;
882
883         for (i=0; i<lck->num_share_modes; i++) {
884                 struct share_mode_entry *e = &lck->share_modes[i];
885                 if (is_valid_share_mode_entry(entry) &&
886                     is_valid_share_mode_entry(e) &&
887                     share_modes_identical(e, entry)) {
888                         return e;
889                 }
890                 if (is_deferred_open_entry(entry) &&
891                     is_deferred_open_entry(e) &&
892                     deferred_open_identical(e, entry)) {
893                         return e;
894                 }
895         }
896         return NULL;
897 }
898
899 /*******************************************************************
900  Del the share mode of a file for this process. Return the number of
901  entries left.
902 ********************************************************************/
903
904 BOOL del_share_mode(struct share_mode_lock *lck, files_struct *fsp)
905 {
906         struct share_mode_entry entry, *e;
907
908         fill_share_mode_entry(&entry, fsp, 0, 0);
909
910         e = find_share_mode_entry(lck, &entry);
911         if (e == NULL) {
912                 return False;
913         }
914
915         e->op_type = UNUSED_SHARE_MODE_ENTRY;
916         lck->modified = True;
917         return True;
918 }
919
920 void del_deferred_open_entry(struct share_mode_lock *lck, uint16 mid)
921 {
922         struct share_mode_entry entry, *e;
923
924         fill_deferred_open_entry(&entry, timeval_zero(),
925                                  lck->dev, lck->ino, mid);
926
927         e = find_share_mode_entry(lck, &entry);
928         if (e == NULL) {
929                 return;
930         }
931
932         e->op_type = UNUSED_SHARE_MODE_ENTRY;
933         lck->modified = True;
934 }
935
936 /*******************************************************************
937  Remove an oplock mid and mode entry from a share mode.
938 ********************************************************************/
939
940 BOOL remove_share_oplock(struct share_mode_lock *lck, files_struct *fsp)
941 {
942         struct share_mode_entry entry, *e;
943
944         fill_share_mode_entry(&entry, fsp, 0, 0);
945
946         e = find_share_mode_entry(lck, &entry);
947         if (e == NULL) {
948                 return False;
949         }
950
951         e->op_mid = 0;
952         e->op_type = NO_OPLOCK;
953         lck->modified = True;
954         return True;
955 }
956
957 /*******************************************************************
958  Downgrade a oplock type from exclusive to level II.
959 ********************************************************************/
960
961 BOOL downgrade_share_oplock(struct share_mode_lock *lck, files_struct *fsp)
962 {
963         struct share_mode_entry entry, *e;
964
965         fill_share_mode_entry(&entry, fsp, 0, 0);
966
967         e = find_share_mode_entry(lck, &entry);
968         if (e == NULL) {
969                 return False;
970         }
971
972         e->op_type = LEVEL_II_OPLOCK;
973         lck->modified = True;
974         return True;
975 }
976
977
978 /*******************************************************************
979  We've just told all the smbd's that our level2 or fake level2 has been
980  written to.
981 ********************************************************************/
982 BOOL remove_all_share_oplocks(struct share_mode_lock *lck, files_struct *fsp)
983 {
984         int i;
985         for (i=0; i<lck->num_share_modes; i++) {
986                 struct share_mode_entry *e = &lck->share_modes[i];
987                 if (!is_valid_share_mode_entry(e)) {
988                         continue;
989                 }
990                 if (e->op_type == NO_OPLOCK) {
991                         continue;
992                 }
993                 e->op_type = NO_OPLOCK;
994                 lck->modified = True;
995         }
996         return True;
997 }
998
999 /****************************************************************************
1000  Deal with the internal needs of setting the delete on close flag. Note that
1001  as the tdb locking is recursive, it is safe to call this from within 
1002  open_file_shared. JRA.
1003 ****************************************************************************/
1004
1005 NTSTATUS can_set_delete_on_close(files_struct *fsp, BOOL delete_on_close,
1006                                  uint32 dosmode)
1007 {
1008         if (!delete_on_close) {
1009                 return NT_STATUS_OK;
1010         }
1011
1012         /*
1013          * Only allow delete on close for writable files.
1014          */
1015
1016         if ((dosmode & aRONLY) &&
1017             !lp_delete_readonly(SNUM(fsp->conn))) {
1018                 DEBUG(10,("can_set_delete_on_close: file %s delete on close "
1019                           "flag set but file attribute is readonly.\n",
1020                           fsp->fsp_name ));
1021                 return NT_STATUS_CANNOT_DELETE;
1022         }
1023
1024         /*
1025          * Only allow delete on close for writable shares.
1026          */
1027
1028         if (!CAN_WRITE(fsp->conn)) {
1029                 DEBUG(10,("can_set_delete_on_close: file %s delete on "
1030                           "close flag set but write access denied on share.\n",
1031                           fsp->fsp_name ));
1032                 return NT_STATUS_ACCESS_DENIED;
1033         }
1034
1035         /*
1036          * Only allow delete on close for files/directories opened with delete
1037          * intent.
1038          */
1039
1040         if (!(fsp->access_mask & DELETE_ACCESS)) {
1041                 DEBUG(10,("can_set_delete_on_close: file %s delete on "
1042                           "close flag set but delete access denied.\n",
1043                           fsp->fsp_name ));
1044                 return NT_STATUS_ACCESS_DENIED;
1045         }
1046
1047         return NT_STATUS_OK;
1048 }
1049
1050 /****************************************************************************
1051  Sets the delete on close flag over all share modes on this file.
1052  Modify the share mode entry for all files open
1053  on this device and inode to tell other smbds we have
1054  changed the delete on close flag. This will be noticed
1055  in the close code, the last closer will delete the file
1056  if flag is set.
1057 ****************************************************************************/
1058
1059 BOOL set_delete_on_close(files_struct *fsp, BOOL delete_on_close)
1060 {
1061         struct share_mode_lock *lck;
1062         
1063         DEBUG(10,("set_delete_on_close: %s delete on close flag for "
1064                   "fnum = %d, file %s\n",
1065                   delete_on_close ? "Adding" : "Removing", fsp->fnum,
1066                   fsp->fsp_name ));
1067
1068         if (fsp->is_stat) {
1069                 return True;
1070         }
1071
1072         lck = get_share_mode_lock(NULL, fsp->dev, fsp->inode, NULL, NULL);
1073         if (lck == NULL) {
1074                 return False;
1075         }
1076         if (lck->delete_on_close != delete_on_close) {
1077                 lck->delete_on_close = delete_on_close;
1078                 lck->modified = True;
1079         }
1080
1081         talloc_free(lck);
1082         return True;
1083 }
1084
1085 static int traverse_fn(TDB_CONTEXT *the_tdb, TDB_DATA kbuf, TDB_DATA dbuf, 
1086                        void *state)
1087 {
1088         struct locking_data *data;
1089         struct share_mode_entry *shares;
1090         const char *sharepath;
1091         const char *fname;
1092         int i;
1093         void (*traverse_callback)(struct share_mode_entry *, const char *, const char *) = state;
1094
1095         /* Ensure this is a locking_key record. */
1096         if (kbuf.dsize != sizeof(struct locking_key))
1097                 return 0;
1098
1099         data = (struct locking_data *)dbuf.dptr;
1100         shares = (struct share_mode_entry *)(dbuf.dptr + sizeof(*data));
1101         sharepath = dbuf.dptr + sizeof(*data) +
1102                 data->u.s.num_share_mode_entries*sizeof(*shares);
1103         fname = dbuf.dptr + sizeof(*data) +
1104                 data->u.s.num_share_mode_entries*sizeof(*shares) +
1105                 strlen(sharepath) + 1;
1106
1107         for (i=0;i<data->u.s.num_share_mode_entries;i++) {
1108                 traverse_callback(&shares[i], sharepath, fname);
1109         }
1110         return 0;
1111 }
1112
1113 /*******************************************************************
1114  Call the specified function on each entry under management by the
1115  share mode system.
1116 ********************************************************************/
1117
1118 int share_mode_forall(void (*fn)(const struct share_mode_entry *, const char *, const char *))
1119 {
1120         if (tdb == NULL)
1121                 return 0;
1122         return tdb_traverse(tdb, traverse_fn, fn);
1123 }