-/*
+/*
Unix SMB/CIFS implementation.
Database interface wrapper
Copyright (C) Jim McDonough <jmcd@us.ibm.com> 2006
Major code contributions from Aleksey Fedoseev (fedoseev@ru.ibm.com)
-
+
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; either version 3 of the License, or
(at your option) any later version.
-
+
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, see <http://www.gnu.org/licenses/>.
*/
#include "util_tdb.h"
/*
- * Fall back using fetch_locked if no genuine fetch operation is provided
+ * Fall back using fetch if no genuine exists operation is provided
*/
-int dbwrap_fallback_fetch(struct db_context *db, TALLOC_CTX *mem_ctx,
- TDB_DATA key, TDB_DATA *data)
+static int dbwrap_fallback_exists(struct db_context *db, TDB_DATA key)
{
- struct db_record *rec;
-
- if (!(rec = db->fetch_locked(db, mem_ctx, key))) {
- return -1;
- }
+ NTSTATUS status = dbwrap_parse_record(db, key, NULL, NULL);
+ return NT_STATUS_IS_OK(status) ? 1 : 0;
+}
- data->dsize = rec->value.dsize;
- data->dptr = talloc_move(mem_ctx, &rec->value.dptr);
- TALLOC_FREE(rec);
- return 0;
+static int delete_record(struct db_record *rec, void *data)
+{
+ NTSTATUS status = dbwrap_record_delete(rec);
+ return NT_STATUS_IS_OK(status) ? 0 : -1;
}
/*
- * Fall back using fetch if no genuine exists operation is provided
+ * Fallback wipe implementation using traverse and delete if no genuine
+ * wipe operation is provided
*/
-
-static int dbwrap_fallback_exists(struct db_context *db, TDB_DATA key)
+static int dbwrap_fallback_wipe(struct db_context *db)
{
- int res = dbwrap_parse_record(db, key, NULL, NULL);
- return ( res == -1) ? 0 : 1;
+ NTSTATUS status = dbwrap_trans_traverse(db, delete_record, NULL);
+ return NT_STATUS_IS_OK(status) ? 0 : -1;
}
+
/*
- * Fall back using fetch if no genuine parse operation is provided
+ * Wrapper functions for the backend methods
*/
-int dbwrap_fallback_parse_record(struct db_context *db, TDB_DATA key,
- int (*parser)(TDB_DATA key,
- TDB_DATA data,
- void *private_data),
- void *private_data)
+TDB_DATA dbwrap_record_get_key(const struct db_record *rec)
{
- TDB_DATA data;
- int res;
+ return rec->key;
+}
+
+TDB_DATA dbwrap_record_get_value(const struct db_record *rec)
+{
+ return rec->value;
+}
+
+NTSTATUS dbwrap_record_store(struct db_record *rec, TDB_DATA data, int flags)
+{
+ return rec->store(rec, data, flags);
+}
+
+NTSTATUS dbwrap_record_delete(struct db_record *rec)
+{
+ return rec->delete_rec(rec);
+}
+
+struct dbwrap_lock_order_state {
+ uint8_t *plock_order_mask;
+ uint8_t bitmask;
+};
+
+static int dbwrap_lock_order_state_destructor(
+ struct dbwrap_lock_order_state *s)
+{
+ *s->plock_order_mask &= ~s->bitmask;
+ return 0;
+}
+
+static struct dbwrap_lock_order_state *dbwrap_check_lock_order(
+ struct db_context *db, TALLOC_CTX *mem_ctx)
+{
+ /*
+ * Store the lock_order of currently locked records as bits in
+ * "lock_order_mask". We only use levels 1,2,3 right now, so a
+ * single uint8_t is enough.
+ */
+ static uint8_t lock_order_mask;
+
+ struct dbwrap_lock_order_state *state;
+ uint8_t idx;
+ int used;
+
+ if (db->lock_order == 0) {
+ /*
+ * lock order 0 is for example for dbwrap_rbt without
+ * real locking. Return state nevertheless to avoid
+ * special cases.
+ */
+ return talloc(mem_ctx, struct dbwrap_lock_order_state);
+ }
+
+ /*
+ * We fill bits from the high bits, to be able to use
+ * "ffs(lock_order_mask)"
+ */
+ idx = sizeof(lock_order_mask)*8 - db->lock_order;
+
+ used = ffs(lock_order_mask);
+
+ DEBUG(1, ("used=%d, lock_order=%d, idx=%d\n", used,
+ (int)db->lock_order, (int)idx));
+
+ if ((used != 0) && (used-1 <= idx)) {
+ DEBUG(0, ("Lock order violation: Trying %d, order_mask=%x\n",
+ (int)db->lock_order, (int)lock_order_mask));
+ return NULL;
+ }
- res = db->fetch(db, talloc_tos(), key, &data);
- if (res != 0) {
- return -1;
+ state = talloc(mem_ctx, struct dbwrap_lock_order_state);
+ if (state == NULL) {
+ DEBUG(1, ("talloc failed\n"));
+ return NULL;
}
+ state->bitmask = 1 << idx;
+ state->plock_order_mask = &lock_order_mask;
+
+ talloc_set_destructor(state, dbwrap_lock_order_state_destructor);
+ lock_order_mask |= state->bitmask;
+
+ return state;
+}
+
+struct db_record *dbwrap_fetch_locked(struct db_context *db,
+ TALLOC_CTX *mem_ctx,
+ TDB_DATA key)
+{
+ struct db_record *rec;
+ struct dbwrap_lock_order_state *lock_order;
- res = parser(key, data, private_data);
- TALLOC_FREE(data.dptr);
- return res;
+ lock_order = dbwrap_check_lock_order(db, talloc_tos());
+ if (lock_order == NULL) {
+ return NULL;
+ }
+ rec = db->fetch_locked(db, mem_ctx, key);
+ if (rec == NULL) {
+ TALLOC_FREE(lock_order);
+ return NULL;
+ }
+ (void)talloc_steal(rec, lock_order);
+ return rec;
}
+struct dbwrap_fetch_state {
+ TALLOC_CTX *mem_ctx;
+ TDB_DATA data;
+};
+
+static void dbwrap_fetch_parser(TDB_DATA key, TDB_DATA data,
+ void *private_data)
+{
+ struct dbwrap_fetch_state *state =
+ (struct dbwrap_fetch_state *)private_data;
+
+ state->data.dsize = data.dsize;
+ state->data.dptr = (uint8_t *)talloc_memdup(state->mem_ctx, data.dptr,
+ data.dsize);
+}
-TDB_DATA dbwrap_fetch(struct db_context *db, TALLOC_CTX *mem_ctx,
- TDB_DATA key)
+NTSTATUS dbwrap_fetch(struct db_context *db, TALLOC_CTX *mem_ctx,
+ TDB_DATA key, TDB_DATA *value)
{
- TDB_DATA result;
+ struct dbwrap_fetch_state state;
+ NTSTATUS status;
- if (db->fetch(db, mem_ctx, key, &result) != 0) {
- return make_tdb_data(NULL, 0);
+ if (value == NULL) {
+ return NT_STATUS_INVALID_PARAMETER;
}
- return result;
+ state.mem_ctx = mem_ctx;
+
+ status = dbwrap_parse_record(db, key, dbwrap_fetch_parser, &state);
+ if (!NT_STATUS_IS_OK(status)) {
+ return status;
+ }
+ if ((state.data.dsize != 0) && (state.data.dptr == NULL)) {
+ return NT_STATUS_NO_MEMORY;
+ }
+ *value = state.data;
+ return NT_STATUS_OK;
}
bool dbwrap_exists(struct db_context *db, TDB_DATA key)
struct db_record *rec;
NTSTATUS status;
- rec = db->fetch_locked(db, talloc_tos(), key);
+ rec = dbwrap_fetch_locked(db, talloc_tos(), key);
if (rec == NULL) {
return NT_STATUS_NO_MEMORY;
}
- status = rec->store(rec, data, flags);
+ status = dbwrap_record_store(rec, data, flags);
TALLOC_FREE(rec);
return status;
}
struct db_record *rec;
NTSTATUS status;
- rec = db->fetch_locked(db, talloc_tos(), key);
+ rec = dbwrap_fetch_locked(db, talloc_tos(), key);
if (rec == NULL) {
return NT_STATUS_NO_MEMORY;
}
- status = rec->delete_rec(rec);
+ status = dbwrap_record_delete(rec);
TALLOC_FREE(rec);
return status;
}
return NT_STATUS_OK;
}
-static int dbwrap_null_parser(TDB_DATA key, TDB_DATA val, void* data)
+static void dbwrap_null_parser(TDB_DATA key, TDB_DATA val, void* data)
{
- return 0;
+ return;
}
-int dbwrap_parse_record(struct db_context *db, TDB_DATA key,
- int (*parser)(TDB_DATA key, TDB_DATA data,
- void *private_data),
- void *private_data)
+NTSTATUS dbwrap_parse_record(struct db_context *db, TDB_DATA key,
+ void (*parser)(TDB_DATA key, TDB_DATA data,
+ void *private_data),
+ void *private_data)
{
if (parser == NULL) {
parser = dbwrap_null_parser;
}
+ return db->parse_record(db, key, parser, private_data);
+}
- if (db->parse_record) {
- return db->parse_record(db, key, parser, private_data);
- } else {
- return dbwrap_fallback_parse_record(db, key, parser, private_data);
+int dbwrap_wipe(struct db_context *db)
+{
+ if (db->wipe == NULL) {
+ return dbwrap_fallback_wipe(db);
}
+ return db->wipe(db);
+}
+
+int dbwrap_get_seqnum(struct db_context *db)
+{
+ return db->get_seqnum(db);
+}
+
+int dbwrap_get_flags(struct db_context *db)
+{
+ return db->get_flags(db);
+}
+
+int dbwrap_transaction_start(struct db_context *db)
+{
+ return db->transaction_start(db);
+}
+
+int dbwrap_transaction_commit(struct db_context *db)
+{
+ return db->transaction_commit(db);
+}
+
+int dbwrap_transaction_cancel(struct db_context *db)
+{
+ return db->transaction_cancel(db);
}
git.samba.org / metze / samba / wip.git / blobdiff