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DEFINITIONS
This source file includes following definitions.
- seen_insert
- tdb_validate_freelist
1 /*
2 Unix SMB/CIFS implementation.
3
4 trivial database library
5
6 Copyright (C) Jeremy Allison 2006
7
8 ** NOTE! The following LGPL license applies to the tdb
9 ** library. This does NOT imply that all of Samba is released
10 ** under the LGPL
11
12 This library is free software; you can redistribute it and/or
13 modify it under the terms of the GNU Lesser General Public
14 License as published by the Free Software Foundation; either
15 version 3 of the License, or (at your option) any later version.
16
17 This library is distributed in the hope that it will be useful,
18 but WITHOUT ANY WARRANTY; without even the implied warranty of
19 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
20 Lesser General Public License for more details.
21
22 You should have received a copy of the GNU Lesser General Public
23 License along with this library; if not, see <http://www.gnu.org/licenses/>.
24 */
25
26 #include "tdb_private.h"
27
28 /* Check the freelist is good and contains no loops.
29 Very memory intensive - only do this as a consistency
30 checker. Heh heh - uses an in memory tdb as the storage
31 for the "seen" record list. For some reason this strikes
32 me as extremely clever as I don't have to write another tree
33 data structure implementation :-).
34 */
35
36 static int seen_insert(struct tdb_context *mem_tdb, tdb_off_t rec_ptr)
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37 {
38 TDB_DATA key, data;
39
40 memset(&data, '\0', sizeof(data));
41 key.dptr = (unsigned char *)&rec_ptr;
42 key.dsize = sizeof(rec_ptr);
43 return tdb_store(mem_tdb, key, data, TDB_INSERT);
44 }
45
46 int tdb_validate_freelist(struct tdb_context *tdb, int *pnum_entries)
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47 {
48 struct tdb_context *mem_tdb = NULL;
49 struct list_struct rec;
50 tdb_off_t rec_ptr, last_ptr;
51 int ret = -1;
52
53 *pnum_entries = 0;
54
55 mem_tdb = tdb_open("flval", tdb->header.hash_size,
56 TDB_INTERNAL, O_RDWR, 0600);
57 if (!mem_tdb) {
58 return -1;
59 }
60
61 if (tdb_lock(tdb, -1, F_WRLCK) == -1) {
62 tdb_close(mem_tdb);
63 return 0;
64 }
65
66 last_ptr = FREELIST_TOP;
67
68 /* Store the FREELIST_TOP record. */
69 if (seen_insert(mem_tdb, last_ptr) == -1) {
70 ret = TDB_ERRCODE(TDB_ERR_CORRUPT, -1);
71 goto fail;
72 }
73
74 /* read in the freelist top */
75 if (tdb_ofs_read(tdb, FREELIST_TOP, &rec_ptr) == -1) {
76 goto fail;
77 }
78
79 while (rec_ptr) {
80
81 /* If we can't store this record (we've seen it
82 before) then the free list has a loop and must
83 be corrupt. */
84
85 if (seen_insert(mem_tdb, rec_ptr)) {
86 ret = TDB_ERRCODE(TDB_ERR_CORRUPT, -1);
87 goto fail;
88 }
89
90 if (tdb_rec_free_read(tdb, rec_ptr, &rec) == -1) {
91 goto fail;
92 }
93
94 /* move to the next record */
95 last_ptr = rec_ptr;
96 rec_ptr = rec.next;
97 *pnum_entries += 1;
98 }
99
100 ret = 0;
101
102 fail:
103
104 tdb_close(mem_tdb);
105 tdb_unlock(tdb, -1, F_WRLCK);
106 return ret;
107 }