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diff --git a/storage/xtradb/include/read0read.h b/storage/xtradb/include/read0read.h
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+++ b/storage/xtradb/include/read0read.h
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+/*****************************************************************************
+
+Copyright (c) 1997, 2012, Oracle and/or its affiliates. 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.,
+51 Franklin Street, Suite 500, Boston, MA 02110-1335 USA
+
+*****************************************************************************/
+
+/**************************************************//**
+@file include/read0read.h
+Cursor read
+
+Created 2/16/1997 Heikki Tuuri
+*******************************************************/
+
+#ifndef read0read_h
+#define read0read_h
+
+#include "univ.i"
+
+
+#include "ut0byte.h"
+#include "ut0lst.h"
+#include "btr0types.h"
+#include "trx0trx.h"
+#include "trx0sys.h"
+#include "read0types.h"
+
+/*********************************************************************//**
+Opens a read view where exactly the transactions serialized before this
+point in time are seen in the view.
+@return	own: read view struct */
+UNIV_INTERN
+read_view_t*
+read_view_open_now(
+/*===============*/
+	trx_id_t	cr_trx_id,	/*!< in: trx_id of creating
+					transaction, or 0 used in purge */
+	read_view_t*&	view);		/*!< in,out: pre-allocated view array or
+					NULL if a new one needs to be created */
+
+/*********************************************************************//**
+Clones a read view object. This function will allocate space for two read
+views contiguously, one identical in size and content as @param view (starting
+at returned pointer) and another view immediately following the trx_ids array.
+The second view will have space for an extra trx_id_t element.
+@return	read view struct */
+UNIV_INTERN
+read_view_t*
+read_view_clone(
+/*============*/
+	const read_view_t*	view,		/*!< in: view to clone */
+	read_view_t*&		prebuilt_clone);/*!< in,out: prebuilt view or
+						NULL */
+/*********************************************************************//**
+Insert the view in the proper order into the trx_sys->view_list. The
+read view list is ordered by read_view_t::low_limit_no in descending order. */
+UNIV_INTERN
+void
+read_view_add(
+/*==========*/
+	read_view_t*	view);		/*!< in: view to add to */
+/*********************************************************************//**
+Makes a copy of the oldest existing read view, or opens a new. The view
+must be closed with ..._close.
+@return	own: read view struct */
+UNIV_INTERN
+read_view_t*
+read_view_purge_open(
+/*=================*/
+	read_view_t*&	clone_view,	/*!< in,out: pre-allocated view that
+					will be used to clone the oldest view if
+					exists */
+	read_view_t*&	view);		/*!< in,out: pre-allocated view array or
+					NULL if a new one needs to be created */
+/*********************************************************************//**
+Remove a read view from the trx_sys->view_list. */
+UNIV_INLINE
+void
+read_view_remove(
+/*=============*/
+	read_view_t*	view,		/*!< in: read view, can be 0 */
+	bool		own_mutex);	/*!< in: true if caller owns the
+					trx_sys_t::mutex */
+/*********************************************************************//**
+Frees memory allocated by a read view. */
+UNIV_INTERN
+void
+read_view_free(
+/*===========*/
+	read_view_t*&	view);	/*< in,out: 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.
+@return	true if sees */
+UNIV_INLINE
+bool
+read_view_sees_trx_id(
+/*==================*/
+	const read_view_t*	view,	/*!< in: read view */
+	trx_id_t		trx_id)	/*!< in: trx id */
+	__attribute__((nonnull, warn_unused_result));
+/*********************************************************************//**
+Prints a read view to file. */
+UNIV_INTERN
+void
+read_view_print(
+/*============*/
+	FILE*			file,	/*!< in: file to print to */
+	const 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_t{
+	ulint		type;	/*!< VIEW_NORMAL, VIEW_HIGH_GRANULARITY */
+	undo_no_t	undo_no;/*!< 0 or if type is
+				VIEW_HIGH_GRANULARITY
+				transaction undo_no when this high-granularity
+				consistent read view was created */
+	trx_id_t	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 */
+	trx_id_t	low_limit_id;
+				/*!< The read should not see any transaction
+				with trx id >= this value. In other words,
+				this is the "high water mark". */
+	trx_id_t	up_limit_id;
+				/*!< The read should see all trx ids which
+				are strictly smaller (<) than this value.
+				In other words,
+				this is the "low water mark". */
+	ulint		n_descr;
+				/*!< Number of cells in the trx_ids array */
+	ulint		max_descr;
+				/*!< Maximum number of cells in the trx_ids
+				array */
+	trx_id_t*	descriptors;
+				/*!< Additional trx ids which the read should
+				not see: typically, these are the read-write
+				active transactions at the time when the read
+				is serialized, except the reading transaction
+				itself; the trx ids in this array are in a
+				ascending order. These trx_ids should be
+				between the "low" and "high" water marks,
+				that is, up_limit_id and low_limit_id. */
+	trx_id_t	creator_trx_id;
+				/*!< trx id of creating transaction, or
+				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_t{
+	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