C++ DBTzero函数代码示例

int
hdb_dn2id_parent(
	Operation *op,
	DB_TXN *txn,
	EntryInfo *ei,
	ID *idp )
{
	struct bdb_info *bdb = (struct bdb_info *) op->o_bd->be_private;
	DB *db = bdb->bi_dn2id->bdi_db;
	DBT		key, data;
	DBC	*cursor;
	int		rc = 0;
	diskNode *d;
	char	*ptr;
	ID	nid;

	DBTzero(&key);
	key.size = sizeof(ID);
	key.data = &nid;
	key.ulen = sizeof(ID);
	key.flags = DB_DBT_USERMEM;
	BDB_ID2DISK( ei->bei_id, &nid );

	DBTzero(&data);
	data.flags = DB_DBT_USERMEM;

	rc = db->cursor( db, txn, &cursor, bdb->bi_db_opflags );
	if ( rc ) return rc;

	data.ulen = sizeof(diskNode) + (SLAP_LDAPDN_MAXLEN * 2);
	d = op->o_tmpalloc( data.ulen, op->o_tmpmemctx );
	data.data = d;

	rc = cursor->c_get( cursor, &key, &data, DB_SET );
	if ( rc == 0 ) {
		if (d->nrdnlen[0] & 0x80) {
			rc = LDAP_OTHER;
		} else {
			db_recno_t dkids;
			ptr = (char *) data.data + data.size - sizeof(ID);
			BDB_DISK2ID( ptr, idp );
			ei->bei_nrdn.bv_len = (d->nrdnlen[0] << 8) | d->nrdnlen[1];
			ber_str2bv( d->nrdn, ei->bei_nrdn.bv_len, 1, &ei->bei_nrdn );
			ei->bei_rdn.bv_len = data.size - sizeof(diskNode) -
				ei->bei_nrdn.bv_len;
			ptr = d->nrdn + ei->bei_nrdn.bv_len + 1;
			ber_str2bv( ptr, ei->bei_rdn.bv_len, 1, &ei->bei_rdn );
			/* How many children does this node have? */
			cursor->c_count( cursor, &dkids, 0 );
			ei->bei_dkids = dkids;
		}
	}
	cursor->c_close( cursor );
	op->o_tmpfree( d, op->o_tmpmemctx );
	return rc;
}

int bdb_tool_entry_open(
	BackendDB *be, int mode )
{
	struct bdb_info *bdb = (struct bdb_info *) be->be_private;

	/* initialize key and data thangs */
	DBTzero( &key );
	DBTzero( &data );
	key.flags = DB_DBT_USERMEM;
	key.data = &nid;
	key.size = key.ulen = sizeof( nid );
	data.flags = DB_DBT_USERMEM;

	if (cursor == NULL) {
		int rc = bdb->bi_id2entry->bdi_db->cursor(
			bdb->bi_id2entry->bdi_db, bdb->bi_cache.c_txn, &cursor,
			bdb->bi_db_opflags );
		if( rc != 0 ) {
			return -1;
		}
	}

	/* Set up for threaded slapindex */
	if (( slapMode & (SLAP_TOOL_QUICK|SLAP_TOOL_READONLY)) == SLAP_TOOL_QUICK ) {
		if ( !bdb_tool_info ) {
#ifdef USE_TRICKLE
			ldap_pvt_thread_mutex_init( &bdb_tool_trickle_mutex );
			ldap_pvt_thread_cond_init( &bdb_tool_trickle_cond );
			ldap_pvt_thread_cond_init( &bdb_tool_trickle_cond_end );
			ldap_pvt_thread_pool_submit( &connection_pool, bdb_tool_trickle_task, bdb->bi_dbenv );
#endif

			ldap_pvt_thread_mutex_init( &bdb_tool_index_mutex );
			ldap_pvt_thread_cond_init( &bdb_tool_index_cond_main );
			ldap_pvt_thread_cond_init( &bdb_tool_index_cond_work );
			if ( bdb->bi_nattrs ) {
				int i;
				bdb_tool_threads = slap_tool_thread_max - 1;
				if ( bdb_tool_threads > 1 ) {
					bdb_tool_index_threads = ch_malloc( bdb_tool_threads * sizeof( int ));
					bdb_tool_index_rec = ch_malloc( bdb->bi_nattrs * sizeof( IndexRec ));
					bdb_tool_index_tcount = bdb_tool_threads - 1;
					for (i=1; i<bdb_tool_threads; i++) {
						int *ptr = ch_malloc( sizeof( int ));
						*ptr = i;
						ldap_pvt_thread_pool_submit( &connection_pool,
							bdb_tool_index_task, ptr );
					}
				}
			}
			bdb_tool_info = bdb;
		}
	}

	return 0;
}

int
bdb_dn2id(
	Operation *op,
	struct berval	*dn,
	EntryInfo *ei,
	DB_TXN *txn,
	DB_LOCK *lock )
{
	struct bdb_info *bdb = (struct bdb_info *) op->o_bd->be_private;
	DB *db = bdb->bi_dn2id->bdi_db;
	DBC	*cursor;
	int		rc;
	DBT		key, data;
	ID		nid;

	Debug( LDAP_DEBUG_TRACE, "=> bdb_dn2id(\"%s\")\n", dn->bv_val, 0, 0 );

	DBTzero( &key );
	key.size = dn->bv_len + 2;
	key.data = op->o_tmpalloc( key.size, op->o_tmpmemctx );
	((char *)key.data)[0] = DN_BASE_PREFIX;
	AC_MEMCPY( &((char *)key.data)[1], dn->bv_val, key.size - 1 );

	/* store the ID */
	DBTzero( &data );
	data.data = &nid;
	data.ulen = sizeof(ID);
	data.flags = DB_DBT_USERMEM;

	rc = db->cursor( db, txn, &cursor, bdb->bi_db_opflags );
	if ( rc ) goto func_leave;

	rc = bdb_dn2id_lock( bdb, dn, 0, txn, lock );
	if ( rc ) goto nolock;

	/* fetch it */
	rc = cursor->c_get( cursor, &key, &data, DB_SET );

nolock:
	cursor->c_close( cursor );
func_leave:

	if( rc != 0 ) {
		Debug( LDAP_DEBUG_TRACE, "<= bdb_dn2id: get failed: %s (%d)\n",
			db_strerror( rc ), rc, 0 );
	} else {
		BDB_DISK2ID( &nid, &ei->bei_id );
		Debug( LDAP_DEBUG_TRACE, "<= bdb_dn2id: got id=0x%lx\n",
			ei->bei_id, 0, 0 );
	}
	op->o_tmpfree( key.data, op->o_tmpmemctx );
	return rc;
}

int
bdb_dn2id_children(
	BackendDB	*be,
	DB_TXN *txn,
	struct berval *dn, 
	int flags )
{
	int		rc;
	DBT		key, data;
	struct bdb_info *bdb = (struct bdb_info *) be->be_private;
	DB *db = bdb->bi_dn2id->bdi_db;
	ID		id;

#ifdef NEW_LOGGING
	LDAP_LOG ( INDEX, ARGS, 
		"=> bdb_dn2id_children( %s )\n", dn->bv_val, 0, 0 );
#else
	Debug( LDAP_DEBUG_TRACE, "=> bdb_dn2id_children( %s )\n",
		dn->bv_val, 0, 0 );
#endif

	DBTzero( &key );
	key.size = dn->bv_len + 2;
	key.data = ch_malloc( key.size );
	((char *)key.data)[0] = DN_ONE_PREFIX;
	AC_MEMCPY( &((char *)key.data)[1], dn->bv_val, key.size - 1 );

	/* we actually could do a empty get... */
	DBTzero( &data );
	data.data = &id;
	data.ulen = sizeof(id);
	data.flags = DB_DBT_USERMEM;
	data.doff = 0;
	data.dlen = sizeof(id);

	rc = db->get( db, txn, &key, &data, bdb->bi_db_opflags | flags );
	free( key.data );

#ifdef NEW_LOGGING
	LDAP_LOG ( INDEX, DETAIL1, 
		"<= bdb_dn2id_children( %s ): %schildren (%d)\n", 
		dn->bv_val, rc == 0 ? "" : ( rc == DB_NOTFOUND ? "no " :
		db_strerror(rc)), rc );
#else
	Debug( LDAP_DEBUG_TRACE, "<= bdb_dn2id_children( %s ): %schildren (%d)\n",
		dn->bv_val,
		rc == 0 ? "" : ( rc == DB_NOTFOUND ? "no " :
			db_strerror(rc) ), rc );
#endif

	return rc;
}

int
hdb_dn2id_children(
	Operation *op,
	DB_TXN *txn,
	Entry *e )
{
	struct bdb_info *bdb = (struct bdb_info *) op->o_bd->be_private;
	DB *db = bdb->bi_dn2id->bdi_db;
	DBT		key, data;
	DBC		*cursor;
	int		rc;
	ID		id;
	diskNode d;

	DBTzero(&key);
	key.size = sizeof(ID);
	key.data = &e->e_id;
	key.flags = DB_DBT_USERMEM;
	BDB_ID2DISK( e->e_id, &id );

	/* IDL cache is in host byte order */
	if ( bdb->bi_idl_cache_size ) {
		rc = bdb_idl_cache_get( bdb, db, &key, NULL );
		if ( rc != LDAP_NO_SUCH_OBJECT ) {
			return rc;
		}
	}

	key.data = &id;
	DBTzero(&data);
	data.data = &d;
	data.ulen = sizeof(d);
	data.flags = DB_DBT_USERMEM | DB_DBT_PARTIAL;
	data.dlen = sizeof(d);

	rc = db->cursor( db, txn, &cursor, bdb->bi_db_opflags );
	if ( rc ) return rc;

	rc = cursor->c_get( cursor, &key, &data, DB_SET );
	if ( rc == 0 ) {
		db_recno_t dkids;
		rc = cursor->c_count( cursor, &dkids, 0 );
		if ( rc == 0 ) {
			BEI(e)->bei_dkids = dkids;
			if ( dkids < 2 ) rc = DB_NOTFOUND;
		}
	}
	cursor->c_close( cursor );
	return rc;
}

/* read a key */
int
bdb_key_read(
	Backend	*be,
	DB *db,
	DB_TXN *txn,
	struct berval *k,
	ID *ids,
	DBC **saved_cursor,
	int get_flag
)
{
	int rc;
	DBT key;

	Debug( LDAP_DEBUG_TRACE, "=> key_read\n", 0, 0, 0 );

	DBTzero( &key );
	bv2DBT(k,&key);
	key.ulen = key.size;
	key.flags = DB_DBT_USERMEM;

	rc = bdb_idl_fetch_key( be, db, txn, &key, ids, saved_cursor, get_flag );

	if( rc != LDAP_SUCCESS ) {
		Debug( LDAP_DEBUG_TRACE, "<= bdb_index_read: failed (%d)\n",
			rc, 0, 0 );
	} else {
		Debug( LDAP_DEBUG_TRACE, "<= bdb_index_read %ld candidates\n",
			(long) BDB_IDL_N(ids), 0, 0 );
	}

	return rc;
}

static int
bdb_cache_entry_db_lock( struct bdb_info *bdb, DB_TXN *txn, EntryInfo *ei,
	int rw, int tryOnly, DB_LOCK *lock )
{
#ifdef NO_DB_LOCK
	return 0;
#else
	int       rc;
	DBT       lockobj;
	int       db_rw;

	if ( !lock ) return 0;

	if (rw)
		db_rw = DB_LOCK_WRITE;
	else
		db_rw = DB_LOCK_READ;

	DBTzero( &lockobj );
	lockobj.data = &ei->bei_id;
	lockobj.size = sizeof(ei->bei_id) + 1;

	rc = LOCK_GET(bdb->bi_dbenv, TXN_ID(txn), tryOnly ? DB_LOCK_NOWAIT : 0,
					&lockobj, db_rw, lock);
	if (rc && !tryOnly) {
		Debug( LDAP_DEBUG_TRACE,
			"bdb_cache_entry_db_lock: entry %ld, rw %d, rc %d\n",
			ei->bei_id, rw, rc );
	}
	return rc;
#endif /* NO_DB_LOCK */
}

int bdb_last_id( BackendDB *be, DB_TXN *tid )
{
	struct bdb_info *bdb = (struct bdb_info *) be->be_private;
	int rc;
	ID id = 0;
	unsigned char idbuf[sizeof(ID)];
	DBT key, data;
	DBC *cursor;

	DBTzero( &key );
	key.flags = DB_DBT_USERMEM;
	key.data = (char *) idbuf;
	key.ulen = sizeof( idbuf );

	DBTzero( &data );
	data.flags = DB_DBT_USERMEM | DB_DBT_PARTIAL;

	/* Get a read cursor */
	rc = bdb->bi_id2entry->bdi_db->cursor( bdb->bi_id2entry->bdi_db,
		tid, &cursor, 0 );

	if (rc == 0) {
		rc = cursor->c_get(cursor, &key, &data, DB_LAST);
		cursor->c_close(cursor);
	}

	switch(rc) {
	case DB_NOTFOUND:
		rc = 0;
		break;
	case 0:
		BDB_DISK2ID( idbuf, &id );
		break;

	default:
		Debug( LDAP_DEBUG_ANY,
			"=> bdb_last_id: get failed: %s (%d)\n",
			db_strerror(rc), rc, 0 );
		goto done;
	}

	bdb->bi_lastid = id;

done:
	return rc;
}

int
bdb_dn2id_children(
	Operation *op,
	DB_TXN *txn,
	Entry *e )
{
	DBT		key, data;
	struct bdb_info *bdb = (struct bdb_info *) op->o_bd->be_private;
	DB *db = bdb->bi_dn2id->bdi_db;
	ID		id;
	int		rc;

	Debug( LDAP_DEBUG_TRACE, "=> bdb_dn2id_children(\"%s\")\n",
		e->e_nname.bv_val, 0, 0 );
	DBTzero( &key );
	key.size = e->e_nname.bv_len + 2;
	key.data = op->o_tmpalloc( key.size, op->o_tmpmemctx );
	((char *)key.data)[0] = DN_ONE_PREFIX;
	AC_MEMCPY( &((char *)key.data)[1], e->e_nname.bv_val, key.size - 1 );

	if ( bdb->bi_idl_cache_size ) {
		rc = bdb_idl_cache_get( bdb, db, &key, NULL );
		if ( rc != LDAP_NO_SUCH_OBJECT ) {
			op->o_tmpfree( key.data, op->o_tmpmemctx );
			return rc;
		}
	}
	/* we actually could do a empty get... */
	DBTzero( &data );
	data.data = &id;
	data.ulen = sizeof(id);
	data.flags = DB_DBT_USERMEM;
	data.doff = 0;
	data.dlen = sizeof(id);

	rc = db->get( db, txn, &key, &data, bdb->bi_db_opflags );
	op->o_tmpfree( key.data, op->o_tmpmemctx );

	Debug( LDAP_DEBUG_TRACE, "<= bdb_dn2id_children(\"%s\"): %s (%d)\n",
		e->e_nname.bv_val,
		rc == 0 ? "" : ( rc == DB_NOTFOUND ? "no " :
			db_strerror(rc) ), rc );

	return rc;
}

int
bdb_dn2idl(
	Operation *op,
	DB_TXN *txn,
	struct berval *ndn,
	EntryInfo *ei,
	ID *ids,
	ID *stack )
{
	int		rc;
	DBT		key;
	struct bdb_info *bdb = (struct bdb_info *) op->o_bd->be_private;
	DB *db = bdb->bi_dn2id->bdi_db;
	int prefix = ( op->ors_scope == LDAP_SCOPE_ONELEVEL )
		? DN_ONE_PREFIX : DN_SUBTREE_PREFIX;

	Debug( LDAP_DEBUG_TRACE, "=> bdb_dn2idl(\"%s\")\n",
		ndn->bv_val, 0, 0 );

#ifndef	BDB_MULTIPLE_SUFFIXES
	if ( prefix == DN_SUBTREE_PREFIX
		&& ( ei->bei_id == 0 ||
		( ei->bei_parent->bei_id == 0 && op->o_bd->be_suffix[0].bv_len ))) {
		BDB_IDL_ALL(bdb, ids);
		return 0;
	}
#endif

	DBTzero( &key );
	key.size = ndn->bv_len + 2;
	key.ulen = key.size;
	key.flags = DB_DBT_USERMEM;
	key.data = op->o_tmpalloc( key.size, op->o_tmpmemctx );
	((char *)key.data)[0] = prefix;
	AC_MEMCPY( &((char *)key.data)[1], ndn->bv_val, key.size - 1 );

	BDB_IDL_ZERO( ids );
	rc = bdb_idl_fetch_key( op->o_bd, db, txn, &key, ids, NULL, 0 );

	if( rc != 0 ) {
		Debug( LDAP_DEBUG_TRACE,
			"<= bdb_dn2idl: get failed: %s (%d)\n",
			db_strerror( rc ), rc, 0 );

	} else {
		Debug( LDAP_DEBUG_TRACE,
			"<= bdb_dn2idl: id=%ld first=%ld last=%ld\n",
			(long) ids[0],
			(long) BDB_IDL_FIRST( ids ), (long) BDB_IDL_LAST( ids ) );
	}

	op->o_tmpfree( key.data, op->o_tmpmemctx );
	return rc;
}

int bdb_id2entry_put(
	BackendDB *be,
	DB_TXN *tid,
	Entry *e,
	int flag )
{
	struct bdb_info *bdb = (struct bdb_info *) be->be_private;
	DB *db = bdb->bi_id2entry->bdi_db;
	DBT key, data;
	struct berval bv;
	int rc;
#ifdef BDB_HIER
	struct berval odn, ondn;

	/* We only store rdns, and they go in the id2parent database. */

	odn = e->e_name; ondn = e->e_nname;

	e->e_name = slap_empty_bv;
	e->e_nname = slap_empty_bv;
#endif
	DBTzero( &key );
	key.data = (char *) &e->e_id;
	key.size = sizeof(ID);

	rc = entry_encode( e, &bv );
#ifdef BDB_HIER
	e->e_name = odn; e->e_nname = ondn;
#endif
	if( rc != LDAP_SUCCESS ) {
		return -1;
	}

	DBTzero( &data );
	bv2DBT( &bv, &data );

	rc = db->put( db, tid, &key, &data, flag );

	free( bv.bv_val );
	return rc;
}

/* This function initializes the trees at startup time. */
int bdb_build_tree(
	Backend *be
)
{
	struct bdb_info *bdb = (struct bdb_info *) be->be_private;
	int rc;
	DBC *cursor;
	DBT key, data;
	ID id;
	idNode *node;

	bdb->bi_tree = NULL;

	rc = bdb->bi_id2parent->bdi_db->cursor(
		bdb->bi_id2parent->bdi_db, NULL, &cursor,
		bdb->bi_db_opflags );
	if( rc != 0 ) {
		return NOID;
	}

	DBTzero( &key );
	DBTzero( &data );
	key.data = (char *)&id;
	key.ulen = sizeof( id );
	key.flags = DB_DBT_USERMEM;
	data.flags = DB_DBT_MALLOC;

	while (cursor->c_get( cursor, &key, &data, DB_NEXT ) == 0) {
		bdb_add_node( id, data.data, bdb );
	}
	cursor->c_close( cursor );

	rc = avl_apply(bdb->bi_tree, bdb_insert_kid, bdb->bi_tree,
		-1, AVL_INORDER );

	return rc;
}

/* Add or remove stuff from index files */
int
bdb_key_change(
	Backend *be,
	DB *db,
	DB_TXN *txn,
	struct berval *k,
	ID id,
	int op
)
{
	int	rc;
	DBT	key;

	Debug( LDAP_DEBUG_TRACE, "=> key_change(%s,%lx)\n",
		op == SLAP_INDEX_ADD_OP ? "ADD":"DELETE", (long) id, 0 );

	DBTzero( &key );
	bv2DBT(k,&key);
	key.ulen = key.size;
	key.flags = DB_DBT_USERMEM;

	if (op == SLAP_INDEX_ADD_OP) {
		/* Add values */

#ifdef BDB_TOOL_IDL_CACHING
		if ( slapMode & SLAP_TOOL_QUICK )
			rc = bdb_tool_idl_add( be, db, txn, &key, id );
		else
#endif
			rc = bdb_idl_insert_key( be, db, txn, &key, id );
		if ( rc == DB_KEYEXIST ) rc = 0;
	} else {
		/* Delete values */
		rc = bdb_idl_delete_key( be, db, txn, &key, id );
		if ( rc == DB_NOTFOUND ) rc = 0;
	}

	Debug( LDAP_DEBUG_TRACE, "<= key_change %d\n", rc, 0, 0 );

	return rc;
}

/* Atomically release and reacquire a lock */
int
bdb_cache_entry_db_relock(
	struct bdb_info *bdb,
	DB_TXN *txn,
	EntryInfo *ei,
	int rw,
	int tryOnly,
	DB_LOCK *lock )
{
#ifdef NO_DB_LOCK
	return 0;
#else
	int	rc;
	DBT	lockobj;
	DB_LOCKREQ list[2];

	if ( !lock ) return 0;

	DBTzero( &lockobj );
	lockobj.data = &ei->bei_id;
	lockobj.size = sizeof(ei->bei_id) + 1;

	list[0].op = DB_LOCK_PUT;
	list[0].lock = *lock;
	list[1].op = DB_LOCK_GET;
	list[1].lock = *lock;
	list[1].mode = rw ? DB_LOCK_WRITE : DB_LOCK_READ;
	list[1].obj = &lockobj;
	rc = bdb->bi_dbenv->lock_vec(bdb->bi_dbenv, TXN_ID(txn), tryOnly ? DB_LOCK_NOWAIT : 0,
		list, 2, NULL );

	if (rc && !tryOnly) {
		Debug( LDAP_DEBUG_TRACE,
			"bdb_cache_entry_db_relock: entry %ld, rw %d, rc %d\n",
			ei->bei_id, rw, rc );
	} else {
		*lock = list[1].lock;
	}
	return rc;
#endif
}

int bdb_id2entry_delete(
	BackendDB *be,
	DB_TXN *tid,
	Entry *e )
{
	struct bdb_info *bdb = (struct bdb_info *) be->be_private;
	DB *db = bdb->bi_id2entry->bdi_db;
	DBT key;
	int rc;

	bdb_cache_delete_entry(&bdb->bi_cache, e);

	DBTzero( &key );
	key.data = (char *) &e->e_id;
	key.size = sizeof(ID);

	/* delete from database */
	rc = db->del( db, tid, &key, 0 );

	return rc;
}