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diff --git a/storage/xtradb/include/read0read.h b/storage/xtradb/include/read0read.h
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+/*****************************************************************************
+
+Copyright (c) 1997, 2009, Innobase Oy. All Rights Reserved.
+
+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
+
+*****************************************************************************/
+
+/******************************************************
+Cursor read
+
+Created 2/16/1997 Heikki Tuuri
+*******************************************************/
+
+#ifndef read0read_h
+#define read0read_h
+
+#include "univ.i"
+
+
+#include "ut0byte.h"
+#include "ut0lst.h"
+#include "trx0trx.h"
+#include "read0types.h"
+
+/*************************************************************************
+Opens a read view where exactly the transactions serialized before this
+point in time are seen in the view. */
+UNIV_INTERN
+read_view_t*
+read_view_open_now(
+/*===============*/
+					/* out, own: read view struct */
+	dulint		cr_trx_id,	/* in: trx_id of creating
+					transaction, or (0, 0) used in
+					purge */
+	mem_heap_t*	heap);		/* in: memory heap from which
+					allocated */
+/*************************************************************************
+Makes a copy of the oldest existing read view, or opens a new. The view
+must be closed with ..._close. */
+UNIV_INTERN
+read_view_t*
+read_view_oldest_copy_or_open_new(
+/*==============================*/
+					/* out, own: read view struct */
+	dulint		cr_trx_id,	/* in: trx_id of creating
+					transaction, or (0, 0) used in
+					purge */
+	mem_heap_t*	heap);		/* in: memory heap from which
+					allocated */
+/*************************************************************************
+Closes a read view. */
+UNIV_INTERN
+void
+read_view_close(
+/*============*/
+	read_view_t*	view);	/* in: read view */
+/*************************************************************************
+Closes a consistent read view for MySQL. This function is called at an SQL
+statement end if the trx isolation level is <= TRX_ISO_READ_COMMITTED. */
+UNIV_INTERN
+void
+read_view_close_for_mysql(
+/*======================*/
+	trx_t*	trx);	/* in: trx which has a read view */
+/*************************************************************************
+Checks if a read view sees the specified transaction. */
+UNIV_INLINE
+ibool
+read_view_sees_trx_id(
+/*==================*/
+				/* out: TRUE if sees */
+	read_view_t*	view,	/* in: read view */
+	dulint		trx_id);/* in: trx id */
+/*************************************************************************
+Prints a read view to stderr. */
+UNIV_INTERN
+void
+read_view_print(
+/*============*/
+	read_view_t*	view);	/* in: read view */
+/*************************************************************************
+Create a consistent cursor view for mysql to be used in cursors. In this
+consistent read view modifications done by the creating transaction or future
+transactions are not visible. */
+UNIV_INTERN
+cursor_view_t*
+read_cursor_view_create_for_mysql(
+/*==============================*/
+	trx_t*		cr_trx);/* in: trx where cursor view is created */
+/*************************************************************************
+Close a given consistent cursor view for mysql and restore global read view
+back to a transaction read view. */
+UNIV_INTERN
+void
+read_cursor_view_close_for_mysql(
+/*=============================*/
+	trx_t*		trx,		/* in: trx */
+	cursor_view_t*	curview);	/* in: cursor view to be closed */
+/*************************************************************************
+This function sets a given consistent cursor view to a transaction
+read view if given consistent cursor view is not NULL. Otherwise, function
+restores a global read view to a transaction read view. */
+UNIV_INTERN
+void
+read_cursor_set_for_mysql(
+/*======================*/
+	trx_t*		trx,	/* in: transaction where cursor is set */
+	cursor_view_t*	curview);/* in: consistent cursor view to be set */
+
+/* Read view lists the trx ids of those transactions for which a consistent
+read should not see the modifications to the database. */
+
+struct read_view_struct{
+	ulint	type;		/* VIEW_NORMAL, VIEW_HIGH_GRANULARITY */
+	dulint	undo_no;	/* (0, 0) or if type is VIEW_HIGH_GRANULARITY
+				transaction undo_no when this high-granularity
+				consistent read view was created */
+	dulint	low_limit_no;	/* The view does not need to see the undo
+				logs for transactions whose transaction number
+				is strictly smaller (<) than this value: they
+				can be removed in purge if not needed by other
+				views */
+	dulint	low_limit_id;	/* The read should not see any transaction
+				with trx id >= this value */
+	dulint	up_limit_id;	/* The read should see all trx ids which
+				are strictly smaller (<) than this value */
+	ulint	n_trx_ids;	/* Number of cells in the trx_ids array */
+	dulint*	trx_ids;	/* Additional trx ids which the read should
+				not see: typically, these are the active
+				transactions at the time when the read is
+				serialized, except the reading transaction
+				itself; the trx ids in this array are in a
+				descending order */
+	dulint	creator_trx_id;	/* trx id of creating transaction, or
+				(0, 0) used in purge */
+	UT_LIST_NODE_T(read_view_t) view_list;
+				/* List of read views in trx_sys */
+};
+
+/* Read view types */
+#define VIEW_NORMAL		1	/* Normal consistent read view
+					where transaction does not see changes
+					made by active transactions except
+					creating transaction. */
+#define VIEW_HIGH_GRANULARITY	2	/* High-granularity read view where
+					transaction does not see changes
+					made by active transactions and own
+					changes after a point in time when this
+					read view was created. */
+
+/* Implement InnoDB framework to support consistent read views in
+cursors. This struct holds both heap where consistent read view
+is allocated and pointer to a read view. */
+
+struct cursor_view_struct{
+	mem_heap_t*	heap;
+				/* Memory heap for the cursor view */
+	read_view_t*	read_view;
+				/* Consistent read view of the cursor*/
+	ulint		n_mysql_tables_in_use;
+				/* number of Innobase tables used in the
+				processing of this cursor */
+};
+
+#ifndef UNIV_NONINL
+#include "read0read.ic"
+#endif
+
+#endif