Revert original fix for Bug 12612184 and the follow up fix for

Bug 12704861.

Bug 12704861 fix was revno: 3504.1.1 (rb://693)
Bug 12612184 fix was revno: 3445.1.10 (rb://678)

2 files changed, 31 insertions, 38 deletions

diff --git a/storage/innobase/page/page0cur.c b/storage/innobase/page/page0cur.c
index b8c492328e8..936762b986a 100644
--- a/storage/innobase/page/page0cur.c
+++ b/storage/innobase/page/page0cur.c
@@ -1,6 +1,6 @@
 /*****************************************************************************
 
-Copyright (c) 1994, 2011, Oracle and/or its affiliates. All Rights Reserved.
+Copyright (c) 1994, 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
@@ -1180,15 +1180,14 @@ page_cur_insert_rec_zip_reorg(
 	/* Before trying to reorganize the page,
 	store the number of preceding records on the page. */
 	pos = page_rec_get_n_recs_before(rec);
-	ut_ad(pos > 0);
 
 	if (page_zip_reorganize(block, index, mtr)) {
 		/* The page was reorganized: Find rec by seeking to pos,
 		and update *current_rec. */
-		if (pos > 1) {
-			rec = page_rec_get_nth(page, pos - 1);
-		} else {
-			rec = page + PAGE_NEW_INFIMUM;
+		rec = page + PAGE_NEW_INFIMUM;
+
+		while (--pos) {
+			rec = page + rec_get_next_offs(rec, TRUE);
 		}
 
 		*current_rec = rec;
@@ -1284,12 +1283,6 @@ page_cur_insert_rec_zip(
 			insert_rec = page_cur_insert_rec_zip_reorg(
 				current_rec, block, index, insert_rec,
 				page, page_zip, mtr);
-#ifdef UNIV_DEBUG
-			if (insert_rec) {
-				rec_offs_make_valid(
-					insert_rec, index, offsets);
-			}
-#endif /* UNIV_DEBUG */
 		}
 
 		return(insert_rec);
diff --git a/storage/innobase/page/page0page.c b/storage/innobase/page/page0page.c
index 1c74a1d5cab..6064d028ae1 100644
--- a/storage/innobase/page/page0page.c
+++ b/storage/innobase/page/page0page.c
@@ -1,6 +1,6 @@
 /*****************************************************************************
 
-Copyright (c) 1994, 2011, Oracle and/or its affiliates. All Rights Reserved.
+Copyright (c) 1994, 2010, 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
@@ -1465,54 +1465,55 @@ page_dir_balance_slot(
 	}
 }
 
+#ifndef UNIV_HOTBACKUP
 /************************************************************//**
-Returns the nth record of the record list.
-This is the inverse function of page_rec_get_n_recs_before().
-@return	nth record */
+Returns the middle record of the record list. If there are an even number
+of records in the list, returns the first record of the upper half-list.
+@return	middle record */
 UNIV_INTERN
-const rec_t*
-page_rec_get_nth_const(
-/*===================*/
-	const page_t*	page,	/*!< in: page */
-	ulint		nth)	/*!< in: nth record */
+rec_t*
+page_get_middle_rec(
+/*================*/
+	page_t*	page)	/*!< in: page */
 {
-	const page_dir_slot_t*	slot;
+	page_dir_slot_t*	slot;
+	ulint			middle;
 	ulint			i;
 	ulint			n_owned;
-	const rec_t*		rec;
+	ulint			count;
+	rec_t*			rec;
 
-	ut_ad(nth < UNIV_PAGE_SIZE / (REC_N_NEW_EXTRA_BYTES + 1));
+	/* This many records we must leave behind */
+	middle = (page_get_n_recs(page) + PAGE_HEAP_NO_USER_LOW) / 2;
+
+	count = 0;
 
 	for (i = 0;; i++) {
 
 		slot = page_dir_get_nth_slot(page, i);
 		n_owned = page_dir_slot_get_n_owned(slot);
 
-		if (n_owned > nth) {
+		if (count + n_owned > middle) {
 			break;
 		} else {
-			nth -= n_owned;
+			count += n_owned;
 		}
 	}
 
 	ut_ad(i > 0);
 	slot = page_dir_get_nth_slot(page, i - 1);
-	rec = page_dir_slot_get_rec(slot);
+	rec = (rec_t*) page_dir_slot_get_rec(slot);
+	rec = page_rec_get_next(rec);
 
-	if (page_is_comp(page)) {
-		do {
-			rec = page_rec_get_next_low(rec, TRUE);
-			ut_ad(rec);
-		} while (nth--);
-	} else {
-		do {
-			rec = page_rec_get_next_low(rec, FALSE);
-			ut_ad(rec);
-		} while (nth--);
+	/* There are now count records behind rec */
+
+	for (i = 0; i < middle - count; i++) {
+		rec = page_rec_get_next(rec);
 	}
 
 	return(rec);
 }
+#endif /* !UNIV_HOTBACKUP */
 
 /***************************************************************//**
 Returns the number of records before the given record in chain.
@@ -1574,7 +1575,6 @@ page_rec_get_n_recs_before(
 	n--;
 
 	ut_ad(n >= 0);
-	ut_ad(n < UNIV_PAGE_SIZE / (REC_N_NEW_EXTRA_BYTES + 1));
 
 	return((ulint) n);
 }