From eff16d7593c4ec7e6cdf1adc71561ddc3749f3ff Mon Sep 17 00:00:00 2001
From: Sergei Golubchik <serg@mariadb.org>
Date: Fri, 9 Feb 2024 23:50:26 +0100
Subject: [PATCH] Revert "MDEV-15458 Segfault in heap_scan() upon UPDATE after
 ADD SYSTEM VERSIONING"

This partially reverts 43623f04a98

Engines have to set ::position() after ::write_row(), otherwise
the server won't be able to refer to the row just inserted.
This is important for high-level indexes.

heap part isn't reverted, so heap doesn't support high-level indexes.
to fix this, it'll need info->lastpos in addition to info->current_ptr
---
 sql/sql_delete.cc         | 25 ++++++++++++++++---------
 storage/maria/ma_write.c  |  4 ++--
 storage/myisam/mi_write.c |  1 +
 3 files changed, 19 insertions(+), 11 deletions(-)

diff --git a/sql/sql_delete.cc b/sql/sql_delete.cc
index f6fee04e776..7120fa21189 100644
--- a/sql/sql_delete.cc
+++ b/sql/sql_delete.cc
@@ -296,15 +296,22 @@ int TABLE::delete_row()
 
   store_record(this, record[1]);
   vers_update_end();
-  int err= file->ha_update_row(record[1], record[0]);
-  /*
-     MDEV-23644: we get HA_ERR_FOREIGN_DUPLICATE_KEY iff we already got history
-     row with same trx_id which is the result of foreign key action, so we
-     don't need one more history row.
-  */
-  if (err == HA_ERR_FOREIGN_DUPLICATE_KEY)
-    return file->ha_delete_row(record[0]);
-  return err;
+  int err;
+  if ((err= file->extra(HA_EXTRA_REMEMBER_POS)))
+    return err;
+  if ((err= file->ha_update_row(record[1], record[0])))
+  {
+    /*
+      MDEV-23644: we get HA_ERR_FOREIGN_DUPLICATE_KEY iff we already got
+      history row with same trx_id which is the result of foreign key action,
+      so we don't need one more history row.
+    */
+    if (err == HA_ERR_FOREIGN_DUPLICATE_KEY)
+      file->ha_delete_row(record[0]);
+    else
+      return err;
+  }
+  return file->extra(HA_EXTRA_RESTORE_POS);
 }
 
 
diff --git a/storage/maria/ma_write.c b/storage/maria/ma_write.c
index ba8583cacc8..80cd0c416e3 100644
--- a/storage/maria/ma_write.c
+++ b/storage/maria/ma_write.c
@@ -89,7 +89,7 @@ int maria_write(MARIA_HA *info, const uchar *record)
   MARIA_SHARE *share= info->s;
   uint i;
   int save_errno;
-  MARIA_RECORD_POS filepos, oldpos= info->cur_row.lastpos;
+  MARIA_RECORD_POS filepos;
   uchar *buff;
   my_bool lock_tree= share->lock_key_trees;
   my_bool fatal_error;
@@ -303,7 +303,7 @@ int maria_write(MARIA_HA *info, const uchar *record)
   share->state.changed|= STATE_NOT_MOVABLE | STATE_NOT_ZEROFILLED;
   info->state->changed= 1;
 
-  info->cur_row.lastpos= oldpos;
+  info->cur_row.lastpos= filepos;
   _ma_writeinfo(info, WRITEINFO_UPDATE_KEYFILE);
   if (info->invalidator != 0)
   {
diff --git a/storage/myisam/mi_write.c b/storage/myisam/mi_write.c
index 71d4b62026b..57fa58cfb24 100644
--- a/storage/myisam/mi_write.c
+++ b/storage/myisam/mi_write.c
@@ -153,6 +153,7 @@ int mi_write(MI_INFO *info, const uchar *record)
   info->update= (HA_STATE_CHANGED | HA_STATE_AKTIV | HA_STATE_WRITTEN |
 		 HA_STATE_ROW_CHANGED);
   info->state->records++;
+  info->lastpos=filepos;
   myisam_log_record(MI_LOG_WRITE,info,record,filepos,0);
   (void) _mi_writeinfo(info, WRITEINFO_UPDATE_KEYFILE);
   if (info->invalidator != 0)