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diff --git a/storage/innobase/include/row0undo.h b/storage/innobase/include/row0undo.h
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+++ b/storage/innobase/include/row0undo.h
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+/******************************************************
+Row undo
+
+(c) 1997 Innobase Oy
+
+Created 1/8/1997 Heikki Tuuri
+*******************************************************/
+
+#ifndef row0undo_h
+#define row0undo_h
+
+#include "univ.i"
+#include "mtr0mtr.h"
+#include "trx0sys.h"
+#include "btr0types.h"
+#include "btr0pcur.h"
+#include "dict0types.h"
+#include "trx0types.h"
+#include "que0types.h"
+#include "row0types.h"
+
+/************************************************************************
+Creates a row undo node to a query graph. */
+
+undo_node_t*
+row_undo_node_create(
+/*=================*/
+				/* out, own: undo node */
+	trx_t*		trx,	/* in: transaction */
+	que_thr_t*	parent,	/* in: parent node, i.e., a thr node */
+	mem_heap_t*	heap);	/* in: memory heap where created */
+/***************************************************************
+Looks for the clustered index record when node has the row reference.
+The pcur in node is used in the search. If found, stores the row to node,
+and stores the position of pcur, and detaches it. The pcur must be closed
+by the caller in any case. */
+
+ibool
+row_undo_search_clust_to_pcur(
+/*==========================*/
+				/* out: TRUE if found; NOTE the node->pcur
+				must be closed by the caller, regardless of
+				the return value */
+	undo_node_t*	node);	/* in: row undo node */
+/***************************************************************
+Undoes a row operation in a table. This is a high-level function used
+in SQL execution graphs. */
+
+que_thr_t*
+row_undo_step(
+/*==========*/
+				/* out: query thread to run next or NULL */
+	que_thr_t*	thr);	/* in: query thread */
+
+/* A single query thread will try to perform the undo for all successive
+versions of a clustered index record, if the transaction has modified it
+several times during the execution which is rolled back. It may happen
+that the task is transferred to another query thread, if the other thread
+is assigned to handle an undo log record in the chain of different versions
+of the record, and the other thread happens to get the x-latch to the
+clustered index record at the right time.
+	If a query thread notices that the clustered index record it is looking
+for is missing, or the roll ptr field in the record doed not point to the
+undo log record the thread was assigned to handle, then it gives up the undo
+task for that undo log record, and fetches the next. This situation can occur
+just in the case where the transaction modified the same record several times
+and another thread is currently doing the undo for successive versions of
+that index record. */
+
+/* Undo node structure */
+
+struct undo_node_struct{
+	que_common_t	common;	/* node type: QUE_NODE_UNDO */
+	ulint		state;	/* node execution state */
+	trx_t*		trx;	/* trx for which undo is done */
+	dulint		roll_ptr;/* roll pointer to undo log record */
+	trx_undo_rec_t*	undo_rec;/* undo log record */
+	dulint		undo_no;/* undo number of the record */
+	ulint		rec_type;/* undo log record type: TRX_UNDO_INSERT_REC,
+				... */
+	dulint		new_roll_ptr; /* roll ptr to restore to clustered index
+				record */
+	dulint		new_trx_id; /* trx id to restore to clustered index
+				record */
+	btr_pcur_t	pcur;	/* persistent cursor used in searching the
+				clustered index record */
+	dict_table_t*	table;	/* table where undo is done; NOTE that the
+				table has to be released explicitly with
+				dict_table_release */
+	ulint		cmpl_info;/* compiler analysis of an update */
+	upd_t*		update;	/* update vector for a clustered index record */
+	dtuple_t*	ref;	/* row reference to the next row to handle */
+	dtuple_t*	row;	/* a copy (also fields copied to heap) of the
+				row to handle */
+	dict_index_t*	index;	/* the next index whose record should be
+				handled */
+	mem_heap_t*	heap;	/* memory heap used as auxiliary storage for
+				row; this must be emptied after undo is tried
+				on a row */
+};
+
+/* Execution states for an undo node */
+#define	UNDO_NODE_FETCH_NEXT	1	/* we should fetch the next undo log
+					record */
+#define	UNDO_NODE_PREV_VERS	2	/* the roll ptr to previous version of
+					a row is stored in node, and undo
+					should be done based on it */
+#define UNDO_NODE_INSERT	3
+#define UNDO_NODE_MODIFY	4
+
+
+#ifndef UNIV_NONINL
+#include "row0undo.ic"
+#endif
+
+#endif