BUG#32943: Fixed buggy lock handling of ALTER TABLE for partitioning

mysql-test/r/partition_range.result:
  Added new test cases for lock tables and ALTER TABLE for
  partitions, also added a test case with a trigger.
mysql-test/t/partition_range.test:
  Added new test cases for lock tables and ALTER TABLE for
  partitions, also added a test case with a trigger.
sql/mysql_priv.h:
  Added WFRM_KEEP_SHARE for use of code not to be used otherwise
sql/sql_partition.cc:
  Removed get_name_lock and release_name_lock, use
  close_data_files_and_morph_locks which leaves an
  exclusive name lock after completing.
  Reopen table after completing if under lock tables
  Updated comments
sql/sql_table.cc:
  Ensure that code to set partition syntax isn't used other than
  when specifically asked to do it.

1 files changed, 22 insertions, 0 deletions

diff --git a/mysql-test/r/partition_range.result b/mysql-test/r/partition_range.result
index 4da79704ec3..4c6459a09e3 100644
--- a/mysql-test/r/partition_range.result
+++ b/mysql-test/r/partition_range.result
@@ -1,4 +1,26 @@
 drop table if exists t1, t2;
+create table t1 (a integer)
+partition by range (a)
+( partition p0 values less than (4),
+partition p1 values less than (100));
+create trigger tr1 before insert on t1
+for each row begin
+set @a = 1;
+end|
+alter table t1 drop partition p0;
+drop table t1;
+create table t1 (a integer)
+partition by range (a)
+( partition p0 values less than (4),
+partition p1 values less than (100));
+LOCK TABLES t1 WRITE;
+alter table t1 drop partition p0;
+alter table t1 reorganize partition p1 into
+( partition p0 values less than (4),
+partition p1 values less than (100));
+alter table t1 add partition ( partition p2 values less than (200));
+UNLOCK TABLES;
+drop table t1;
 create table t1 (a int unsigned)
 partition by range (a)
 (partition pnull values less than (0),