From a175314c3e5827eb193872241446f2f8f5c9d33c Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sat, 4 May 2024 20:07:14 +0200 Subject: Adding upstream version 1:10.5.12. Signed-off-by: Daniel Baumann --- storage/myisammrg/myrg_rprev.c | 53 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 53 insertions(+) create mode 100644 storage/myisammrg/myrg_rprev.c (limited to 'storage/myisammrg/myrg_rprev.c') diff --git a/storage/myisammrg/myrg_rprev.c b/storage/myisammrg/myrg_rprev.c new file mode 100644 index 00000000..72765f5d --- /dev/null +++ b/storage/myisammrg/myrg_rprev.c @@ -0,0 +1,53 @@ +/* Copyright (c) 2000-2003, 2005-2007 MySQL AB + Use is subject to license terms + + 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, Fifth Floor, Boston, MA 02110-1335 USA */ + +#include "myrg_def.h" + + /* + Read previous row with the same key as previous read + */ + +int myrg_rprev(MYRG_INFO *info, uchar *buf, int inx) +{ + int err; + MI_INFO *mi; + + if (!info->current_table) + return (HA_ERR_KEY_NOT_FOUND); + + /* at first, do rprev for the table found before */ + if ((err=mi_rprev(info->current_table->table,NULL,inx))) + { + if (err == HA_ERR_END_OF_FILE) + { + queue_remove_top(&(info->by_key)); + if (!info->by_key.elements) + return HA_ERR_END_OF_FILE; + } + else + return err; + } + else + { + /* Found here, adding to queue */ + queue_top(&(info->by_key))=(uchar *)(info->current_table); + queue_replace_top(&(info->by_key)); + } + + /* now, mymerge's read_prev is as simple as one queue_top */ + mi=(info->current_table=(MYRG_TABLE *)queue_top(&(info->by_key)))->table; + return _myrg_mi_read_record(mi,buf); +} -- cgit v1.2.3