2 Unix SMB/CIFS implementation.
3 Database interface wrapper
4 Copyright (C) Jim McDonough <jmcd@us.ibm.com> 2006
6 Major code contributions from Aleksey Fedoseev (fedoseev@ru.ibm.com)
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 3 of the License, or
11 (at your option) any later version.
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.
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>.
23 #include "dbwrap/dbwrap.h"
24 #include "dbwrap/dbwrap_private.h"
25 #include "lib/util/util_tdb.h"
28 * Fall back using fetch if no genuine exists operation is provided
31 static int dbwrap_fallback_exists(struct db_context
*db
, TDB_DATA key
)
33 NTSTATUS status
= dbwrap_parse_record(db
, key
, NULL
, NULL
);
34 return NT_STATUS_IS_OK(status
) ? 1 : 0;
37 static int delete_record(struct db_record
*rec
, void *data
)
39 NTSTATUS status
= dbwrap_record_delete(rec
);
40 return NT_STATUS_IS_OK(status
) ? 0 : -1;
44 * Fallback wipe implementation using traverse and delete if no genuine
45 * wipe operation is provided
47 static int dbwrap_fallback_wipe(struct db_context
*db
)
49 NTSTATUS status
= dbwrap_trans_traverse(db
, delete_record
, NULL
);
50 return NT_STATUS_IS_OK(status
) ? 0 : -1;
53 static int do_nothing(struct db_record
*rec
, void *unused
)
59 * Fallback check operation: just traverse.
61 static int dbwrap_fallback_check(struct db_context
*db
)
63 NTSTATUS status
= dbwrap_traverse_read(db
, do_nothing
, NULL
, NULL
);
64 return NT_STATUS_IS_OK(status
) ? 0 : -1;
68 * Wrapper functions for the backend methods
71 TDB_DATA
dbwrap_record_get_key(const struct db_record
*rec
)
76 TDB_DATA
dbwrap_record_get_value(const struct db_record
*rec
)
81 NTSTATUS
dbwrap_record_store(struct db_record
*rec
, TDB_DATA data
, int flags
)
84 struct db_context
*db
;
86 status
= rec
->store(rec
, data
, flags
);
87 if (!NT_STATUS_IS_OK(status
)) {
91 if (db
->stored_callback
!= NULL
) {
92 db
->stored_callback(db
, rec
,
93 db
->stored_callback_private_data
);
98 void dbwrap_set_stored_callback(
99 struct db_context
*db
,
100 void (*cb
)(struct db_context
*db
, struct db_record
*rec
,
104 db
->stored_callback
= cb
;
105 db
->stored_callback_private_data
= private_data
;
108 NTSTATUS
dbwrap_record_delete(struct db_record
*rec
)
111 struct db_context
*db
;
113 status
= rec
->delete_rec(rec
);
114 if (!NT_STATUS_IS_OK(status
)) {
118 if (db
->stored_callback
!= NULL
) {
119 db
->stored_callback(db
, rec
,
120 db
->stored_callback_private_data
);
125 struct dbwrap_lock_order_state
{
126 uint8_t *plock_order_mask
;
130 static int dbwrap_lock_order_state_destructor(
131 struct dbwrap_lock_order_state
*s
)
133 *s
->plock_order_mask
&= ~s
->bitmask
;
137 static struct dbwrap_lock_order_state
*dbwrap_check_lock_order(
138 struct db_context
*db
, TALLOC_CTX
*mem_ctx
)
141 * Store the lock_order of currently locked records as bits in
142 * "lock_order_mask". We only use levels 1,2,3 right now, so a
143 * single uint8_t is enough.
145 static uint8_t lock_order_mask
;
147 struct dbwrap_lock_order_state
*state
;
151 if (db
->lock_order
== 0) {
153 * lock order 0 is for example for dbwrap_rbt without
154 * real locking. Return state nevertheless to avoid
157 return talloc(mem_ctx
, struct dbwrap_lock_order_state
);
161 * We fill bits from the high bits, to be able to use
162 * "ffs(lock_order_mask)"
164 idx
= sizeof(lock_order_mask
)*8 - db
->lock_order
;
166 used
= ffs(lock_order_mask
);
168 DEBUG(5, ("used=%d, lock_order=%d, idx=%d\n", used
,
169 (int)db
->lock_order
, (int)idx
));
171 if ((used
!= 0) && (used
-1 <= idx
)) {
172 DEBUG(0, ("Lock order violation: Trying %d, order_mask=%x\n",
173 (int)db
->lock_order
, (int)lock_order_mask
));
177 state
= talloc(mem_ctx
, struct dbwrap_lock_order_state
);
179 DEBUG(1, ("talloc failed\n"));
182 state
->bitmask
= 1 << idx
;
183 state
->plock_order_mask
= &lock_order_mask
;
185 talloc_set_destructor(state
, dbwrap_lock_order_state_destructor
);
186 lock_order_mask
|= state
->bitmask
;
191 static struct db_record
*dbwrap_fetch_locked_internal(
192 struct db_context
*db
, TALLOC_CTX
*mem_ctx
, TDB_DATA key
,
193 struct db_record
*(*db_fn
)(struct db_context
*db
, TALLOC_CTX
*mem_ctx
,
196 struct db_record
*rec
;
197 struct dbwrap_lock_order_state
*lock_order
;
198 TALLOC_CTX
*frame
= talloc_stackframe();
200 lock_order
= dbwrap_check_lock_order(db
, frame
);
201 if (lock_order
== NULL
) {
205 rec
= db_fn(db
, mem_ctx
, key
);
210 (void)talloc_steal(rec
, lock_order
);
216 struct db_record
*dbwrap_fetch_locked(struct db_context
*db
,
220 return dbwrap_fetch_locked_internal(db
, mem_ctx
, key
,
224 struct db_record
*dbwrap_try_fetch_locked(struct db_context
*db
,
228 return dbwrap_fetch_locked_internal(
231 ? db
->try_fetch_locked
: db
->fetch_locked
);
234 struct db_record
*dbwrap_fetch_locked_timeout(struct db_context
*db
,
237 unsigned int timeout
)
239 struct db_record
*rec
;
240 struct dbwrap_lock_order_state
*lock_order
;
241 TALLOC_CTX
*frame
= talloc_stackframe();
243 lock_order
= dbwrap_check_lock_order(db
, frame
);
244 if (lock_order
== NULL
) {
248 rec
= db
->fetch_locked_timeout
249 ? db
->fetch_locked_timeout(db
, mem_ctx
, key
, timeout
)
250 : db
->fetch_locked(db
, mem_ctx
, key
);
255 (void)talloc_steal(rec
, lock_order
);
261 struct db_context
*dbwrap_record_get_db(struct db_record
*rec
)
266 struct dbwrap_fetch_state
{
271 static void dbwrap_fetch_parser(TDB_DATA key
, TDB_DATA data
,
274 struct dbwrap_fetch_state
*state
=
275 (struct dbwrap_fetch_state
*)private_data
;
277 state
->data
.dsize
= data
.dsize
;
278 state
->data
.dptr
= (uint8_t *)talloc_memdup(state
->mem_ctx
, data
.dptr
,
282 NTSTATUS
dbwrap_fetch(struct db_context
*db
, TALLOC_CTX
*mem_ctx
,
283 TDB_DATA key
, TDB_DATA
*value
)
285 struct dbwrap_fetch_state state
;
289 return NT_STATUS_INVALID_PARAMETER
;
292 state
.mem_ctx
= mem_ctx
;
294 status
= dbwrap_parse_record(db
, key
, dbwrap_fetch_parser
, &state
);
295 if (!NT_STATUS_IS_OK(status
)) {
298 if ((state
.data
.dsize
!= 0) && (state
.data
.dptr
== NULL
)) {
299 return NT_STATUS_NO_MEMORY
;
305 bool dbwrap_exists(struct db_context
*db
, TDB_DATA key
)
308 if (db
->exists
!= NULL
) {
309 result
= db
->exists(db
, key
);
311 result
= dbwrap_fallback_exists(db
,key
);
313 return (result
== 1);
316 NTSTATUS
dbwrap_store(struct db_context
*db
, TDB_DATA key
,
317 TDB_DATA data
, int flags
)
319 struct db_record
*rec
;
321 TALLOC_CTX
*frame
= talloc_stackframe();
323 rec
= dbwrap_fetch_locked(db
, frame
, key
);
326 return NT_STATUS_NO_MEMORY
;
329 status
= dbwrap_record_store(rec
, data
, flags
);
334 NTSTATUS
dbwrap_delete(struct db_context
*db
, TDB_DATA key
)
336 struct db_record
*rec
;
338 TALLOC_CTX
*frame
= talloc_stackframe();
340 rec
= dbwrap_fetch_locked(db
, frame
, key
);
343 return NT_STATUS_NO_MEMORY
;
345 status
= dbwrap_record_delete(rec
);
350 NTSTATUS
dbwrap_traverse(struct db_context
*db
,
351 int (*f
)(struct db_record
*, void*),
355 int ret
= db
->traverse(db
, f
, private_data
);
358 return NT_STATUS_INTERNAL_DB_CORRUPTION
;
368 NTSTATUS
dbwrap_traverse_read(struct db_context
*db
,
369 int (*f
)(struct db_record
*, void*),
373 int ret
= db
->traverse_read(db
, f
, private_data
);
376 return NT_STATUS_INTERNAL_DB_CORRUPTION
;
386 static void dbwrap_null_parser(TDB_DATA key
, TDB_DATA val
, void* data
)
391 NTSTATUS
dbwrap_parse_record(struct db_context
*db
, TDB_DATA key
,
392 void (*parser
)(TDB_DATA key
, TDB_DATA data
,
396 if (parser
== NULL
) {
397 parser
= dbwrap_null_parser
;
399 return db
->parse_record(db
, key
, parser
, private_data
);
402 int dbwrap_wipe(struct db_context
*db
)
404 if (db
->wipe
== NULL
) {
405 return dbwrap_fallback_wipe(db
);
410 int dbwrap_check(struct db_context
*db
)
412 if (db
->check
== NULL
) {
413 return dbwrap_fallback_check(db
);
415 return db
->check(db
);
418 int dbwrap_get_seqnum(struct db_context
*db
)
420 return db
->get_seqnum(db
);
423 int dbwrap_transaction_start(struct db_context
*db
)
425 return db
->transaction_start(db
);
428 int dbwrap_transaction_commit(struct db_context
*db
)
430 return db
->transaction_commit(db
);
433 int dbwrap_transaction_cancel(struct db_context
*db
)
435 return db
->transaction_cancel(db
);
438 void dbwrap_db_id(struct db_context
*db
, const uint8_t **id
, size_t *idlen
)
440 db
->id(db
, id
, idlen
);