*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/access/transam/xact.c,v 1.225 2006/07/30 02:07:18 alvherre Exp $
+ * $PostgreSQL: pgsql/src/backend/access/transam/xact.c,v 1.226 2006/08/27 19:11:46 tgl Exp $
*
*-------------------------------------------------------------------------
*/
typedef TransactionStateData *TransactionState;
/*
- * childXids is currently implemented as an Oid List, relying on the
- * assumption that TransactionIds are no wider than Oid. We use these
- * macros to provide some isolation in case that changes in the future.
- */
-#define lfirst_xid(lc) ((TransactionId) lfirst_oid(lc))
-#define lappend_xid(list, datum) lappend_oid(list, (Oid) (datum))
-
-/*
* CurrentTransactionState always points to the current transaction state
* block. It will point to TopTransactionStateData when not in a
* transaction at all, or when in a top-level transaction.
* (At the moment, ints and Oids are the same size, but they may not
* always be so; try to be careful to maintain the distinction.)
*
+ * There is also limited support for lists of TransactionIds; since these
+ * are used in only one or two places, we don't provide a full implementation,
+ * but map them onto Oid lists. This effectively assumes that TransactionId
+ * is no wider than Oid and both are unsigned types.
+ *
*
* Portions Copyright (c) 1996-2006, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $PostgreSQL: pgsql/src/include/nodes/pg_list.h,v 1.54 2006/03/05 15:58:57 momjian Exp $
+ * $PostgreSQL: pgsql/src/include/nodes/pg_list.h,v 1.55 2006/08/27 19:11:46 tgl Exp $
*
*-------------------------------------------------------------------------
*/
#define list_make4_oid(x1,x2,x3,x4) lcons_oid(x1, list_make3_oid(x2, x3, x4))
/*
+ * Limited support for lists of TransactionIds, mapped onto lists of Oids
+ */
+#define lfirst_xid(lc) ((TransactionId) lfirst_oid(lc))
+#define lappend_xid(list, datum) lappend_oid(list, (Oid) (datum))
+
+/*
* foreach -
* a convenience macro which loops through the list
*/