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diff --git a/storage/innobase/include/trx0purge.h b/storage/innobase/include/trx0purge.h
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+/*****************************************************************************
+
+Copyright (c) 1996, 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
+
+*****************************************************************************/
+
+/**************************************************//**
+@file include/trx0purge.h
+Purge old versions
+
+Created 3/26/1996 Heikki Tuuri
+*******************************************************/
+
+#ifndef trx0purge_h
+#define trx0purge_h
+
+#include "univ.i"
+#include "trx0types.h"
+#include "mtr0mtr.h"
+#include "trx0sys.h"
+#include "que0types.h"
+#include "page0page.h"
+#include "usr0sess.h"
+#include "fil0fil.h"
+
+/** The global data structure coordinating a purge */
+extern trx_purge_t*	purge_sys;
+
+/** A dummy undo record used as a return value when we have a whole undo log
+which needs no purge */
+extern trx_undo_rec_t	trx_purge_dummy_rec;
+
+/********************************************************************//**
+Calculates the file address of an undo log header when we have the file
+address of its history list node.
+@return	file address of the log */
+UNIV_INLINE
+fil_addr_t
+trx_purge_get_log_from_hist(
+/*========================*/
+	fil_addr_t	node_addr);	/*!< in: file address of the history
+					list node of the log */
+/*****************************************************************//**
+Checks if trx_id is >= purge_view: then it is guaranteed that its update
+undo log still exists in the system.
+@return TRUE if is sure that it is preserved, also if the function
+returns FALSE, it is possible that the undo log still exists in the
+system */
+UNIV_INTERN
+ibool
+trx_purge_update_undo_must_exist(
+/*=============================*/
+	trx_id_t	trx_id);/*!< in: transaction id */
+/********************************************************************//**
+Creates the global purge system control structure and inits the history
+mutex. */
+UNIV_INTERN
+void
+trx_purge_sys_create(void);
+/*======================*/
+/********************************************************************//**
+Adds the update undo log as the first log in the history list. Removes the
+update undo log segment from the rseg slot if it is too big for reuse. */
+UNIV_INTERN
+void
+trx_purge_add_update_undo_to_history(
+/*=================================*/
+	trx_t*	trx,		/*!< in: transaction */
+	page_t*	undo_page,	/*!< in: update undo log header page,
+				x-latched */
+	mtr_t*	mtr);		/*!< in: mtr */
+/********************************************************************//**
+Fetches the next undo log record from the history list to purge. It must be
+released with the corresponding release function.
+@return copy of an undo log record or pointer to trx_purge_dummy_rec,
+if the whole undo log can skipped in purge; NULL if none left */
+UNIV_INTERN
+trx_undo_rec_t*
+trx_purge_fetch_next_rec(
+/*=====================*/
+	roll_ptr_t*	roll_ptr,/*!< out: roll pointer to undo record */
+	trx_undo_inf_t** cell,	/*!< out: storage cell for the record in the
+				purge array */
+	mem_heap_t*	heap);	/*!< in: memory heap where copied */
+/*******************************************************************//**
+Releases a reserved purge undo record. */
+UNIV_INTERN
+void
+trx_purge_rec_release(
+/*==================*/
+	trx_undo_inf_t*	cell);	/*!< in: storage cell */
+/*******************************************************************//**
+This function runs a purge batch.
+@return	number of undo log pages handled in the batch */
+UNIV_INTERN
+ulint
+trx_purge(void);
+/*===========*/
+/******************************************************************//**
+Prints information of the purge system to stderr. */
+UNIV_INTERN
+void
+trx_purge_sys_print(void);
+/*======================*/
+
+/** The control structure used in the purge operation */
+struct trx_purge_struct{
+	ulint		state;		/*!< Purge system state */
+	sess_t*		sess;		/*!< System session running the purge
+					query */
+	trx_t*		trx;		/*!< System transaction running the purge
+					query: this trx is not in the trx list
+					of the trx system and it never ends */
+	que_t*		query;		/*!< The query graph which will do the
+					parallelized purge operation */
+	rw_lock_t	latch;		/*!< The latch protecting the purge view.
+					A purge operation must acquire an
+					x-latch here for the instant at which
+					it changes the purge view: an undo
+					log operation can prevent this by
+					obtaining an s-latch here. */
+	read_view_t*	view;		/*!< The purge will not remove undo logs
+					which are >= this view (purge view) */
+	mutex_t		mutex;		/*!< Mutex protecting the fields below */
+	ulint		n_pages_handled;/*!< Approximate number of undo log
+					pages processed in purge */
+	ulint		handle_limit;	/*!< Target of how many pages to get
+					processed in the current purge */
+	/*------------------------------*/
+	/* The following two fields form the 'purge pointer' which advances
+	during a purge, and which is used in history list truncation */
+
+	trx_id_t	purge_trx_no;	/*!< Purge has advanced past all
+					transactions whose number is less
+					than this */
+	undo_no_t	purge_undo_no;	/*!< Purge has advanced past all records
+					whose undo number is less than this */
+	/*-----------------------------*/
+	ibool		next_stored;	/*!< TRUE if the info of the next record
+					to purge is stored below: if yes, then
+					the transaction number and the undo
+					number of the record are stored in
+					purge_trx_no and purge_undo_no above */
+	trx_rseg_t*	rseg;		/*!< Rollback segment for the next undo
+					record to purge */
+	ulint		page_no;	/*!< Page number for the next undo
+					record to purge, page number of the
+					log header, if dummy record */
+	ulint		offset;		/*!< Page offset for the next undo
+					record to purge, 0 if the dummy
+					record */
+	ulint		hdr_page_no;	/*!< Header page of the undo log where
+					the next record to purge belongs */
+	ulint		hdr_offset;	/*!< Header byte offset on the page */
+	/*-----------------------------*/
+	trx_undo_arr_t*	arr;		/*!< Array of transaction numbers and
+					undo numbers of the undo records
+					currently under processing in purge */
+	mem_heap_t*	heap;		/*!< Temporary storage used during a
+					purge: can be emptied after purge
+					completes */
+};
+
+#define TRX_PURGE_ON		1	/* purge operation is running */
+#define TRX_STOP_PURGE		2	/* purge operation is stopped, or
+					it should be stopped */
+#ifndef UNIV_NONINL
+#include "trx0purge.ic"
+#endif
+
+#endif