1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
|
/** BEGIN COPYRIGHT BLOCK
* This Program is free software; you can redistribute it and/or modify it under
* the terms of the GNU General Public License as published by the Free Software
* Foundation; version 2 of the License.
*
* This Program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
* FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along with
* this Program; if not, write to the Free Software Foundation, Inc., 59 Temple
* Place, Suite 330, Boston, MA 02111-1307 USA.
*
* In addition, as a special exception, Red Hat, Inc. gives You the additional
* right to link the code of this Program with code not covered under the GNU
* General Public License ("Non-GPL Code") and to distribute linked combinations
* including the two, subject to the limitations in this paragraph. Non-GPL Code
* permitted under this exception must only link to the code of this Program
* through those well defined interfaces identified in the file named EXCEPTION
* found in the source code files (the "Approved Interfaces"). The files of
* Non-GPL Code may instantiate templates or use macros or inline functions from
* the Approved Interfaces without causing the resulting work to be covered by
* the GNU General Public License. Only Red Hat, Inc. may make changes or
* additions to the list of Approved Interfaces. You must obey the GNU General
* Public License in all respects for all of the Program code and other code used
* in conjunction with the Program except the Non-GPL Code covered by this
* exception. If you modify this file, you may extend this exception to your
* version of the file, but you are not obligated to do so. If you do not wish to
* provide this exception without modification, you must delete this exception
* statement from your version and license this file solely under the GPL without
* exception.
*
*
* Copyright (C) 2009 Red Hat, Inc.
* All rights reserved.
* END COPYRIGHT BLOCK **/
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include "back-ldbm.h"
static int usn_get_last_usn(Slapi_Backend *be, PRUint64 *last_usn);
/*
* USN counter part in the backend
* - If usn is enabled,
* - For each backend,
* - Get the last USN index key
* - Initialize the slapi counter with the next USN (last USN + 1)
*
* dn: cn=entryusn,cn=default indexes,cn=config,cn=ldbm database,cn=plugins,cn=
* config
* objectClass: top
* objectClass: nsIndex
* cn: entryusn
* nsSystemIndex: true
* nsIndexType: eq
*/
void
ldbm_usn_init(struct ldbminfo *li)
{
Slapi_DN *sdn = NULL;
void *node = NULL;
int rc = 0;
Slapi_Backend *be = NULL;
PRUint64 last_usn = 0;
PRUint64 global_last_usn = INITIALUSN;
int isglobal = config_get_entryusn_global();
int isfirst = 1;
/* if USN is not enabled, return immediately */
if (!plugin_enabled("USN", li->li_identity)) {
goto bail;
}
/* Search each namingContext in turn */
for ( sdn = slapi_get_first_suffix( &node, 0 ); sdn != NULL;
sdn = slapi_get_next_suffix_ext( &node, 0 )) {
be = slapi_mapping_tree_find_backend_for_sdn(sdn);
slapi_log_error(SLAPI_LOG_BACKLDBM, "ldbm_usn_init",
"backend: %s%s%s\n", be->be_name, isglobal?" ":"", isglobal?"(global mode)":"");
rc = usn_get_last_usn(be, &last_usn);
if (0 == rc) { /* only when the last usn is available */
if (isglobal) {
if (isfirst) {
li->li_global_usn_counter = slapi_counter_new();
isfirst = 0;
}
/* share one counter */
be->be_usn_counter = li->li_global_usn_counter;
/* Initialize global_last_usn;
* Set the largest last_usn among backends */
if ((global_last_usn == INITIALUSN) ||
((last_usn != INITIALUSN) && (global_last_usn < last_usn))) {
global_last_usn = last_usn;
}
slapi_counter_set_value(be->be_usn_counter, global_last_usn);
/* stores next usn */
slapi_counter_increment(be->be_usn_counter);
} else {
be->be_usn_counter = slapi_counter_new();
slapi_counter_set_value(be->be_usn_counter, last_usn);
/* stores next usn */
slapi_counter_increment(be->be_usn_counter);
}
}
}
bail:
return;
}
/*
* usn_ge_last_usn: get the last USN from the entryusn equality index
*/
static int
usn_get_last_usn(Slapi_Backend *be, PRUint64 *last_usn)
{
struct attrinfo *ai = NULL;
int rc = -1;
DB *db = NULL;
DBC *dbc = NULL;
DBT key; /* For the last usn */
DBT value;
if (NULL == last_usn) {
return rc;
}
memset(&key, 0, sizeof(key));
memset(&value, 0, sizeof(key));
*last_usn = INITIALUSN; /* to start from 0 */
/* Open the entryusn index */
ainfo_get(be, SLAPI_ATTR_ENTRYUSN, &ai);
/* Open the entryusn index file */
rc = dblayer_get_index_file(be, ai, &db, DBOPEN_CREATE);
if (0 != rc) {
/* entryusn.db# is missing; it would be the first time. */
slapi_log_error(SLAPI_LOG_FATAL, "usn_get_last_usn",
"failed to open the entryusn index: %d", rc);
goto bail;
}
/* Get a cursor */
rc = db->cursor(db, NULL, &dbc, 0);
if (0 != rc) {
slapi_log_error(SLAPI_LOG_FATAL, "usn_get_last_usn",
"failed to create a cursor: %d", rc);
goto bail;
}
key.flags = DB_DBT_MALLOC;
value.flags = DB_DBT_MALLOC;
rc = dbc->c_get(dbc, &key, &value, DB_LAST);
if ((0 == rc) && key.data) {
char *p = (char *)key.data;
while ((0 == rc) && ('=' != *p)) { /* get the last elem of equality */
slapi_ch_free(&(key.data));
slapi_ch_free(&(value.data));
rc = dbc->c_get(dbc, &key, &value, DB_PREV);
p = (char *)key.data;
}
if (0 == rc) {
*last_usn = strtoll(++p, (char **)NULL, 0); /* key.data: =num */
}
} else if (DB_NOTFOUND == rc) {
/* if empty, it's okay. This is just a beginning. */
rc = 0;
}
slapi_ch_free(&(key.data));
slapi_ch_free(&(value.data));
bail:
if (dbc) {
dbc->c_close(dbc);
}
if (db) {
dblayer_release_index_file(be, ai, db);
}
return rc;
}
/*
* Whether USN is enabled or not is checked with be_usn_counter.
*/
int
ldbm_usn_enabled(Slapi_Backend *be)
{
return (NULL != be->be_usn_counter);
}
/*
* set last usn to the USN slapi_counter in backend
*/
int
ldbm_set_last_usn(Slapi_Backend *be)
{
PRUint64 last_usn = 0;
int isglobal = config_get_entryusn_global();
int rc = -1;
if (NULL == be) {
slapi_log_error(SLAPI_LOG_FATAL, "ldbm_set_last_usn",
"Empty backend\n");
return rc;
}
if (isglobal) {
struct ldbminfo *li = (struct ldbminfo *)be->be_database->plg_private;
/* destroy old counter, if any */
slapi_counter_destroy(&(li->li_global_usn_counter));
ldbm_usn_init(li);
} else {
slapi_log_error(SLAPI_LOG_BACKLDBM, "ldbm_set_last_usn",
"backend: %s\n", be->be_name);
rc = usn_get_last_usn(be, &last_usn);
if (0 == rc) { /* only when the last usn is available */
/* destroy old counter, if any */
slapi_counter_destroy(&(be->be_usn_counter));
be->be_usn_counter = slapi_counter_new();
slapi_counter_set_value(be->be_usn_counter, last_usn);
slapi_counter_increment(be->be_usn_counter); /* stores next usn */
}
}
return rc;
}
|
