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diff --git a/storage/innobase/include/btr0pcur.h b/storage/innobase/include/btr0pcur.h
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+++ b/storage/innobase/include/btr0pcur.h
@@ -0,0 +1,548 @@
+/*****************************************************************************
+
+Copyright (c) 1996, 2013, 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/btr0pcur.h
+The index tree persistent cursor
+
+Created 2/23/1996 Heikki Tuuri
+*******************************************************/
+
+#ifndef btr0pcur_h
+#define btr0pcur_h
+
+#include "univ.i"
+#include "dict0dict.h"
+#include "data0data.h"
+#include "mtr0mtr.h"
+#include "page0cur.h"
+#include "btr0cur.h"
+#include "btr0btr.h"
+#include "btr0types.h"
+
+/* Relative positions for a stored cursor position */
+#define BTR_PCUR_ON			1
+#define BTR_PCUR_BEFORE			2
+#define BTR_PCUR_AFTER			3
+/* Note that if the tree is not empty, btr_pcur_store_position does not
+use the following, but only uses the above three alternatives, where the
+position is stored relative to a specific record: this makes implementation
+of a scroll cursor easier */
+#define BTR_PCUR_BEFORE_FIRST_IN_TREE	4	/* in an empty tree */
+#define BTR_PCUR_AFTER_LAST_IN_TREE	5	/* in an empty tree */
+
+/**************************************************************//**
+Allocates memory for a persistent cursor object and initializes the cursor.
+@return	own: persistent cursor */
+UNIV_INTERN
+btr_pcur_t*
+btr_pcur_create_for_mysql(void);
+/*============================*/
+
+/**************************************************************//**
+Resets a persistent cursor object, freeing ::old_rec_buf if it is
+allocated and resetting the other members to their initial values. */
+UNIV_INTERN
+void
+btr_pcur_reset(
+/*===========*/
+	btr_pcur_t*	cursor);/*!< in, out: persistent cursor */
+
+/**************************************************************//**
+Frees the memory for a persistent cursor object. */
+UNIV_INTERN
+void
+btr_pcur_free_for_mysql(
+/*====================*/
+	btr_pcur_t*	cursor);	/*!< in, own: persistent cursor */
+/**************************************************************//**
+Copies the stored position of a pcur to another pcur. */
+UNIV_INTERN
+void
+btr_pcur_copy_stored_position(
+/*==========================*/
+	btr_pcur_t*	pcur_receive,	/*!< in: pcur which will receive the
+					position info */
+	btr_pcur_t*	pcur_donate);	/*!< in: pcur from which the info is
+					copied */
+/**************************************************************//**
+Sets the old_rec_buf field to NULL. */
+UNIV_INLINE
+void
+btr_pcur_init(
+/*==========*/
+	btr_pcur_t*	pcur);	/*!< in: persistent cursor */
+/**************************************************************//**
+Initializes and opens a persistent cursor to an index tree. It should be
+closed with btr_pcur_close. */
+UNIV_INLINE
+void
+btr_pcur_open_low(
+/*==============*/
+	dict_index_t*	index,	/*!< in: index */
+	ulint		level,	/*!< in: level in the btree */
+	const dtuple_t*	tuple,	/*!< in: tuple on which search done */
+	ulint		mode,	/*!< in: PAGE_CUR_L, ...;
+				NOTE that if the search is made using a unique
+				prefix of a record, mode should be
+				PAGE_CUR_LE, not PAGE_CUR_GE, as the latter
+				may end up on the previous page from the
+				record! */
+	ulint		latch_mode,/*!< in: BTR_SEARCH_LEAF, ... */
+	btr_pcur_t*	cursor, /*!< in: memory buffer for persistent cursor */
+	const char*	file,	/*!< in: file name */
+	ulint		line,	/*!< in: line where called */
+	mtr_t*		mtr);	/*!< in: mtr */
+#define btr_pcur_open(i,t,md,l,c,m)				\
+	btr_pcur_open_low(i,0,t,md,l,c,__FILE__,__LINE__,m)
+/**************************************************************//**
+Opens an persistent cursor to an index tree without initializing the
+cursor. */
+UNIV_INLINE
+void
+btr_pcur_open_with_no_init_func(
+/*============================*/
+	dict_index_t*	index,	/*!< in: index */
+	const dtuple_t*	tuple,	/*!< in: tuple on which search done */
+	ulint		mode,	/*!< in: PAGE_CUR_L, ...;
+				NOTE that if the search is made using a unique
+				prefix of a record, mode should be
+				PAGE_CUR_LE, not PAGE_CUR_GE, as the latter
+				may end up on the previous page of the
+				record! */
+	ulint		latch_mode,/*!< in: BTR_SEARCH_LEAF, ...;
+				NOTE that if has_search_latch != 0 then
+				we maybe do not acquire a latch on the cursor
+				page, but assume that the caller uses his
+				btr search latch to protect the record! */
+	btr_pcur_t*	cursor, /*!< in: memory buffer for persistent cursor */
+	ulint		has_search_latch,/*!< in: latch mode the caller
+				currently has on btr_search_latch:
+				RW_S_LATCH, or 0 */
+	const char*	file,	/*!< in: file name */
+	ulint		line,	/*!< in: line where called */
+	mtr_t*		mtr);	/*!< in: mtr */
+#define btr_pcur_open_with_no_init(ix,t,md,l,cur,has,m)			\
+	btr_pcur_open_with_no_init_func(ix,t,md,l,cur,has,__FILE__,__LINE__,m)
+
+/*****************************************************************//**
+Opens a persistent cursor at either end of an index. */
+UNIV_INLINE
+void
+btr_pcur_open_at_index_side(
+/*========================*/
+	bool		from_left,	/*!< in: true if open to the low end,
+					false if to the high end */
+	dict_index_t*	index,		/*!< in: index */
+	ulint		latch_mode,	/*!< in: latch mode */
+	btr_pcur_t*	pcur,		/*!< in/out: cursor */
+	bool		init_pcur,	/*!< in: whether to initialize pcur */
+	ulint		level,		/*!< in: level to search for
+					(0=leaf) */
+	mtr_t*		mtr)		/*!< in/out: mini-transaction */
+	__attribute__((nonnull));
+/**************************************************************//**
+Gets the up_match value for a pcur after a search.
+@return number of matched fields at the cursor or to the right if
+search mode was PAGE_CUR_GE, otherwise undefined */
+UNIV_INLINE
+ulint
+btr_pcur_get_up_match(
+/*==================*/
+	const btr_pcur_t*	cursor); /*!< in: persistent cursor */
+/**************************************************************//**
+Gets the low_match value for a pcur after a search.
+@return number of matched fields at the cursor or to the right if
+search mode was PAGE_CUR_LE, otherwise undefined */
+UNIV_INLINE
+ulint
+btr_pcur_get_low_match(
+/*===================*/
+	const btr_pcur_t*	cursor); /*!< in: persistent cursor */
+/**************************************************************//**
+If mode is PAGE_CUR_G or PAGE_CUR_GE, opens a persistent cursor on the first
+user record satisfying the search condition, in the case PAGE_CUR_L or
+PAGE_CUR_LE, on the last user record. If no such user record exists, then
+in the first case sets the cursor after last in tree, and in the latter case
+before first in tree. The latching mode must be BTR_SEARCH_LEAF or
+BTR_MODIFY_LEAF. */
+UNIV_INTERN
+void
+btr_pcur_open_on_user_rec_func(
+/*===========================*/
+	dict_index_t*	index,		/*!< in: index */
+	const dtuple_t*	tuple,		/*!< in: tuple on which search done */
+	ulint		mode,		/*!< in: PAGE_CUR_L, ... */
+	ulint		latch_mode,	/*!< in: BTR_SEARCH_LEAF or
+					BTR_MODIFY_LEAF */
+	btr_pcur_t*	cursor,		/*!< in: memory buffer for persistent
+					cursor */
+	const char*	file,		/*!< in: file name */
+	ulint		line,		/*!< in: line where called */
+	mtr_t*		mtr);		/*!< in: mtr */
+#define btr_pcur_open_on_user_rec(i,t,md,l,c,m)				\
+	btr_pcur_open_on_user_rec_func(i,t,md,l,c,__FILE__,__LINE__,m)
+/**********************************************************************//**
+Positions a cursor at a randomly chosen position within a B-tree. */
+UNIV_INLINE
+void
+btr_pcur_open_at_rnd_pos_func(
+/*==========================*/
+	dict_index_t*	index,		/*!< in: index */
+	ulint		latch_mode,	/*!< in: BTR_SEARCH_LEAF, ... */
+	btr_pcur_t*	cursor,		/*!< in/out: B-tree pcur */
+	const char*	file,		/*!< in: file name */
+	ulint		line,		/*!< in: line where called */
+	mtr_t*		mtr);		/*!< in: mtr */
+#define btr_pcur_open_at_rnd_pos(i,l,c,m)				\
+	btr_pcur_open_at_rnd_pos_func(i,l,c,__FILE__,__LINE__,m)
+/**************************************************************//**
+Frees the possible memory heap of a persistent cursor and sets the latch
+mode of the persistent cursor to BTR_NO_LATCHES.
+WARNING: this function does not release the latch on the page where the
+cursor is currently positioned. The latch is acquired by the
+"move to next/previous" family of functions. Since recursive shared locks
+are not allowed, you must take care (if using the cursor in S-mode) to
+manually release the latch by either calling
+btr_leaf_page_release(btr_pcur_get_block(&pcur), pcur.latch_mode, mtr)
+or by committing the mini-transaction right after btr_pcur_close().
+A subsequent attempt to crawl the same page in the same mtr would cause
+an assertion failure. */
+UNIV_INLINE
+void
+btr_pcur_close(
+/*===========*/
+	btr_pcur_t*	cursor);	/*!< in: persistent cursor */
+/**************************************************************//**
+The position of the cursor is stored by taking an initial segment of the
+record the cursor is positioned on, before, or after, and copying it to the
+cursor data structure, or just setting a flag if the cursor id before the
+first in an EMPTY tree, or after the last in an EMPTY tree. NOTE that the
+page where the cursor is positioned must not be empty if the index tree is
+not totally empty! */
+UNIV_INTERN
+void
+btr_pcur_store_position(
+/*====================*/
+	btr_pcur_t*	cursor, /*!< in: persistent cursor */
+	mtr_t*		mtr);	/*!< in: mtr */
+/**************************************************************//**
+Restores the stored position of a persistent cursor bufferfixing the page and
+obtaining the specified latches. If the cursor position was saved when the
+(1) cursor was positioned on a user record: this function restores the position
+to the last record LESS OR EQUAL to the stored record;
+(2) cursor was positioned on a page infimum record: restores the position to
+the last record LESS than the user record which was the successor of the page
+infimum;
+(3) cursor was positioned on the page supremum: restores to the first record
+GREATER than the user record which was the predecessor of the supremum.
+(4) cursor was positioned before the first or after the last in an empty tree:
+restores to before first or after the last in the tree.
+@return TRUE if the cursor position was stored when it was on a user
+record and it can be restored on a user record whose ordering fields
+are identical to the ones of the original user record */
+UNIV_INTERN
+ibool
+btr_pcur_restore_position_func(
+/*===========================*/
+	ulint		latch_mode,	/*!< in: BTR_SEARCH_LEAF, ... */
+	btr_pcur_t*	cursor,		/*!< in: detached persistent cursor */
+	const char*	file,		/*!< in: file name */
+	ulint		line,		/*!< in: line where called */
+	mtr_t*		mtr);		/*!< in: mtr */
+#define btr_pcur_restore_position(l,cur,mtr)				\
+	btr_pcur_restore_position_func(l,cur,__FILE__,__LINE__,mtr)
+/*********************************************************//**
+Gets the rel_pos field for a cursor whose position has been stored.
+@return	BTR_PCUR_ON, ... */
+UNIV_INLINE
+ulint
+btr_pcur_get_rel_pos(
+/*=================*/
+	const btr_pcur_t*	cursor);/*!< in: persistent cursor */
+/**************************************************************//**
+Commits the mtr and sets the pcur latch mode to BTR_NO_LATCHES,
+that is, the cursor becomes detached.
+Function btr_pcur_store_position should be used before calling this,
+if restoration of cursor is wanted later. */
+UNIV_INLINE
+void
+btr_pcur_commit_specify_mtr(
+/*========================*/
+	btr_pcur_t*	pcur,	/*!< in: persistent cursor */
+	mtr_t*		mtr);	/*!< in: mtr to commit */
+/*********************************************************//**
+Moves the persistent cursor to the next record in the tree. If no records are
+left, the cursor stays 'after last in tree'.
+@return	TRUE if the cursor was not after last in tree */
+UNIV_INLINE
+ibool
+btr_pcur_move_to_next(
+/*==================*/
+	btr_pcur_t*	cursor,	/*!< in: persistent cursor; NOTE that the
+				function may release the page latch */
+	mtr_t*		mtr);	/*!< in: mtr */
+/*********************************************************//**
+Moves the persistent cursor to the previous record in the tree. If no records
+are left, the cursor stays 'before first in tree'.
+@return	TRUE if the cursor was not before first in tree */
+UNIV_INTERN
+ibool
+btr_pcur_move_to_prev(
+/*==================*/
+	btr_pcur_t*	cursor,	/*!< in: persistent cursor; NOTE that the
+				function may release the page latch */
+	mtr_t*		mtr);	/*!< in: mtr */
+/*********************************************************//**
+Moves the persistent cursor to the last record on the same page. */
+UNIV_INLINE
+void
+btr_pcur_move_to_last_on_page(
+/*==========================*/
+	btr_pcur_t*	cursor,	/*!< in: persistent cursor */
+	mtr_t*		mtr);	/*!< in: mtr */
+/*********************************************************//**
+Moves the persistent cursor to the next user record in the tree. If no user
+records are left, the cursor ends up 'after last in tree'.
+@return	TRUE if the cursor moved forward, ending on a user record */
+UNIV_INLINE
+ibool
+btr_pcur_move_to_next_user_rec(
+/*===========================*/
+	btr_pcur_t*	cursor,	/*!< in: persistent cursor; NOTE that the
+				function may release the page latch */
+	mtr_t*		mtr);	/*!< in: mtr */
+/*********************************************************//**
+Moves the persistent cursor to the first record on the next page.
+Releases the latch on the current page, and bufferunfixes it.
+Note that there must not be modifications on the current page,
+as then the x-latch can be released only in mtr_commit. */
+UNIV_INTERN
+void
+btr_pcur_move_to_next_page(
+/*=======================*/
+	btr_pcur_t*	cursor,	/*!< in: persistent cursor; must be on the
+				last record of the current page */
+	mtr_t*		mtr);	/*!< in: mtr */
+/*********************************************************//**
+Moves the persistent cursor backward if it is on the first record
+of the page. Releases the latch on the current page, and bufferunfixes
+it. Note that to prevent a possible deadlock, the operation first
+stores the position of the cursor, releases the leaf latch, acquires
+necessary latches and restores the cursor position again before returning.
+The alphabetical position of the cursor is guaranteed to be sensible
+on return, but it may happen that the cursor is not positioned on the
+last record of any page, because the structure of the tree may have
+changed while the cursor had no latches. */
+UNIV_INTERN
+void
+btr_pcur_move_backward_from_page(
+/*=============================*/
+	btr_pcur_t*	cursor,	/*!< in: persistent cursor, must be on the
+				first record of the current page */
+	mtr_t*		mtr);	/*!< in: mtr */
+#ifdef UNIV_DEBUG
+/*********************************************************//**
+Returns the btr cursor component of a persistent cursor.
+@return	pointer to btr cursor component */
+UNIV_INLINE
+btr_cur_t*
+btr_pcur_get_btr_cur(
+/*=================*/
+	const btr_pcur_t*	cursor);	/*!< in: persistent cursor */
+/*********************************************************//**
+Returns the page cursor component of a persistent cursor.
+@return	pointer to page cursor component */
+UNIV_INLINE
+page_cur_t*
+btr_pcur_get_page_cur(
+/*==================*/
+	const btr_pcur_t*	cursor);	/*!< in: persistent cursor */
+/*********************************************************//**
+Returns the page of a persistent cursor.
+@return	pointer to the page */
+UNIV_INLINE
+page_t*
+btr_pcur_get_page(
+/*==============*/
+	const btr_pcur_t*	cursor);/*!< in: persistent cursor */
+/*********************************************************//**
+Returns the buffer block of a persistent cursor.
+@return	pointer to the block */
+UNIV_INLINE
+buf_block_t*
+btr_pcur_get_block(
+/*===============*/
+	const btr_pcur_t*	cursor);/*!< in: persistent cursor */
+/*********************************************************//**
+Returns the record of a persistent cursor.
+@return	pointer to the record */
+UNIV_INLINE
+rec_t*
+btr_pcur_get_rec(
+/*=============*/
+	const btr_pcur_t*	cursor);/*!< in: persistent cursor */
+#else /* UNIV_DEBUG */
+# define btr_pcur_get_btr_cur(cursor) (&(cursor)->btr_cur)
+# define btr_pcur_get_page_cur(cursor) (&(cursor)->btr_cur.page_cur)
+# define btr_pcur_get_page(cursor) ((cursor)->btr_cur.page_cur.block->frame)
+# define btr_pcur_get_block(cursor) ((cursor)->btr_cur.page_cur.block)
+# define btr_pcur_get_rec(cursor) ((cursor)->btr_cur.page_cur.rec)
+#endif /* UNIV_DEBUG */
+/*********************************************************//**
+Checks if the persistent cursor is on a user record. */
+UNIV_INLINE
+ibool
+btr_pcur_is_on_user_rec(
+/*====================*/
+	const btr_pcur_t*	cursor);/*!< in: persistent cursor */
+/*********************************************************//**
+Checks if the persistent cursor is after the last user record on
+a page. */
+UNIV_INLINE
+ibool
+btr_pcur_is_after_last_on_page(
+/*===========================*/
+	const btr_pcur_t*	cursor);/*!< in: persistent cursor */
+/*********************************************************//**
+Checks if the persistent cursor is before the first user record on
+a page. */
+UNIV_INLINE
+ibool
+btr_pcur_is_before_first_on_page(
+/*=============================*/
+	const btr_pcur_t*	cursor);/*!< in: persistent cursor */
+/*********************************************************//**
+Checks if the persistent cursor is before the first user record in
+the index tree. */
+UNIV_INLINE
+ibool
+btr_pcur_is_before_first_in_tree(
+/*=============================*/
+	btr_pcur_t*	cursor,	/*!< in: persistent cursor */
+	mtr_t*		mtr);	/*!< in: mtr */
+/*********************************************************//**
+Checks if the persistent cursor is after the last user record in
+the index tree. */
+UNIV_INLINE
+ibool
+btr_pcur_is_after_last_in_tree(
+/*===========================*/
+	btr_pcur_t*	cursor,	/*!< in: persistent cursor */
+	mtr_t*		mtr);	/*!< in: mtr */
+/*********************************************************//**
+Moves the persistent cursor to the next record on the same page. */
+UNIV_INLINE
+void
+btr_pcur_move_to_next_on_page(
+/*==========================*/
+	btr_pcur_t*	cursor);/*!< in/out: persistent cursor */
+/*********************************************************//**
+Moves the persistent cursor to the previous record on the same page. */
+UNIV_INLINE
+void
+btr_pcur_move_to_prev_on_page(
+/*==========================*/
+	btr_pcur_t*	cursor);/*!< in/out: persistent cursor */
+/*********************************************************//**
+Moves the persistent cursor to the infimum record on the same page. */
+UNIV_INLINE
+void
+btr_pcur_move_before_first_on_page(
+/*===============================*/
+	btr_pcur_t*	cursor); /*!< in/out: persistent cursor */
+
+/** Position state of persistent B-tree cursor. */
+enum pcur_pos_t {
+	/** The persistent cursor is not positioned. */
+	BTR_PCUR_NOT_POSITIONED = 0,
+	/** The persistent cursor was previously positioned.
+	TODO: currently, the state can be BTR_PCUR_IS_POSITIONED,
+	though it really should be BTR_PCUR_WAS_POSITIONED,
+	because we have no obligation to commit the cursor with
+	mtr; similarly latch_mode may be out of date. This can
+	lead to problems if btr_pcur is not used the right way;
+	all current code should be ok. */
+	BTR_PCUR_WAS_POSITIONED,
+	/** The persistent cursor is positioned by optimistic get to the same
+	record as it was positioned at. Not used for rel_pos == BTR_PCUR_ON.
+	It may need adjustment depending on previous/current search direction
+	and rel_pos. */
+	BTR_PCUR_IS_POSITIONED_OPTIMISTIC,
+	/** The persistent cursor is positioned by index search.
+	Or optimistic get for rel_pos == BTR_PCUR_ON. */
+	BTR_PCUR_IS_POSITIONED
+};
+
+/* The persistent B-tree cursor structure. This is used mainly for SQL
+selects, updates, and deletes. */
+
+struct btr_pcur_t{
+	btr_cur_t	btr_cur;	/*!< a B-tree cursor */
+	ulint		latch_mode;	/*!< see TODO note below!
+					BTR_SEARCH_LEAF, BTR_MODIFY_LEAF,
+					BTR_MODIFY_TREE, or BTR_NO_LATCHES,
+					depending on the latching state of
+					the page and tree where the cursor is
+					positioned; BTR_NO_LATCHES means that
+					the cursor is not currently positioned:
+					we say then that the cursor is
+					detached; it can be restored to
+					attached if the old position was
+					stored in old_rec */
+	ulint		old_stored;	/*!< BTR_PCUR_OLD_STORED
+					or BTR_PCUR_OLD_NOT_STORED */
+	rec_t*		old_rec;	/*!< if cursor position is stored,
+					contains an initial segment of the
+					latest record cursor was positioned
+					either on, before, or after */
+	ulint		old_n_fields;	/*!< number of fields in old_rec */
+	ulint		rel_pos;	/*!< BTR_PCUR_ON, BTR_PCUR_BEFORE, or
+					BTR_PCUR_AFTER, depending on whether
+					cursor was on, before, or after the
+					old_rec record */
+	buf_block_t*	block_when_stored;/* buffer block when the position was
+					stored */
+	ib_uint64_t	modify_clock;	/*!< the modify clock value of the
+					buffer block when the cursor position
+					was stored */
+	enum pcur_pos_t	pos_state;	/*!< btr_pcur_store_position() and
+					btr_pcur_restore_position() state. */
+	ulint		search_mode;	/*!< PAGE_CUR_G, ... */
+	trx_t*		trx_if_known;	/*!< the transaction, if we know it;
+					otherwise this field is not defined;
+					can ONLY BE USED in error prints in
+					fatal assertion failures! */
+	/*-----------------------------*/
+	/* NOTE that the following fields may possess dynamically allocated
+	memory which should be freed if not needed anymore! */
+
+	byte*		old_rec_buf;	/*!< NULL, or a dynamically allocated
+					buffer for old_rec */
+	ulint		buf_size;	/*!< old_rec_buf size if old_rec_buf
+					is not NULL */
+};
+
+#define BTR_PCUR_OLD_STORED	908467085
+#define BTR_PCUR_OLD_NOT_STORED	122766467
+
+#ifndef UNIV_NONINL
+#include "btr0pcur.ic"
+#endif
+
+#endif