Fix for BUG#42112 "Maria: recovery failure (pushbuild2) Assertion `rownr == 0 && new_page' failed"

mysql-test/suite/maria/r/maria-recovery3.result:
  result update
mysql-test/suite/maria/t/maria-recovery3.test:
  Test for BUG#42112; before the bugfix, recovery would assert like this:
  ma_blockrec.c:6051: _ma_apply_redo_insert_row_head_or_tail: Assertion `rownr == 0 && new_page' failed.
storage/maria/ma_create.c:
  Fix for BUG#42112; plus some intentional crashes to test the fix. The bug was that if crash happened during
  TRUNCATE TABLE, in maria_create(), after the index file's state has been written but before its LSNs
  have been updated (so, if crash happened between _ma_state_info_write_sub() and _ma_update_state__lsns_sub()),
  then that would leave a table with create_rename_lsn==0. Recovery would then try old pre-TRUNCATE REDOs
  on this table, and fail as this table is already partly shortened. Fix is to write create_rename_lsn==LSN_MAX
  as soon as TRUNCATE touches the index file, so that Recovery ignores this table. This allows Maria to start;
  the table is still corrupted but the user can successfully repeat TRUNCATE TABLE (which required Maria to start).
storage/maria/ma_delete_all.c:
  A comment.

1 files changed, 22 insertions, 0 deletions

diff --git a/mysql-test/suite/maria/t/maria-recovery3.test b/mysql-test/suite/maria/t/maria-recovery3.test
index baee7978f2b..fc1883b1aa7 100644
--- a/mysql-test/suite/maria/t/maria-recovery3.test
+++ b/mysql-test/suite/maria/t/maria-recovery3.test
@@ -88,6 +88,28 @@ check table t1 extended;
 -- source include/maria_verify_recovery.inc
 drop table t1;
 
+# Test for BUG#42112 "Maria: recovery failure (pushbuild2) Assertion
+# `rownr == 0 && new_page' failed"
+
+let $mvr_restore_old_snapshot=0;
+let $mms_compare_physically=0;
+create table t1 engine=maria select 1;
+-- source include/maria_make_snapshot_for_feeding_recovery.inc
+set global maria_checkpoint_interval=0; # no checkpoints
+insert into t1 values(2);
+truncate table t1;
+-- source include/maria_make_snapshot_for_comparison.inc
+let $mvr_crash_statement= truncate table t1;
+let $mvr_debug_option="+d,maria_flush_whole_log,maria_crash_create_table";
+truncate table t1;
+-- source include/maria_verify_recovery.inc
+# Table is bad but at least Recovery didn't crash and a new truncate
+# can succeed:
+truncate table t1;
+check table t1 extended;
+drop table t1;
+
+
 # clean up everything
 let $mms_purpose=comparison;
 eval drop database mysqltest_for_$mms_purpose;