BUG#39746 - Debug flag breaks struct definition

            (server crash)

Altering a table with fulltext index[es] which use
pluggable fulltext parser may cause server crash
in debug builds.

The problem was that ALTER TABLE code wrongly assigned
fulltext parser name.

Also fixed that altering a table with fulltext index[es]
leave stale fulltext parser locks, which prevent
fulltext parsers from being uninstalled after
ALTER TABLE.

mysql-test/include/have_simple_parser.inc:
  Added support for testing simple fulltext parser.
mysql-test/mysql-test-run.pl:
  Added support for testing simple fulltext parser.
mysql-test/r/fulltext_plugin.result:
  A test case for BUG#39746.
mysql-test/r/have_simple_parser.require:
  Added support for testing simple fulltext parser.
mysql-test/t/fulltext_plugin-master.opt:
  A test case for BUG#39746.
mysql-test/t/fulltext_plugin.test:
  A test case for BUG#39746.
sql/sql_table.cc:
  Fixed that alter table wrongly assigns fulltext parser
  name. parser_name member is only available during
  table creation. When we open existing table we must
  get parser_name from plugin_ref, which is handled
  by plugin_name() macro.
sql/table.cc:
  Moved code that releases fulltext parsers into
  free_table_share(). This fixes stale fulltext parser
  locks set by ALTER TABLE, which are preventing fulltext
  parsers from being uninstalled.

1 files changed, 12 insertions, 11 deletions

diff --git a/sql/table.cc b/sql/table.cc
index 1de47a48513..95753e5353a 100644
--- a/sql/table.cc
+++ b/sql/table.cc
@@ -400,6 +400,8 @@ void init_tmp_table_share(THD *thd, TABLE_SHARE *share, const char *key,
 void free_table_share(TABLE_SHARE *share)
 {
   MEM_ROOT mem_root;
+  uint idx;
+  KEY *key_info;
   DBUG_ENTER("free_table_share");
   DBUG_PRINT("enter", ("table: %s.%s", share->db.str, share->table_name.str));
   DBUG_ASSERT(share->ref_count == 0);
@@ -426,6 +428,16 @@ void free_table_share(TABLE_SHARE *share)
   plugin_unlock(NULL, share->db_plugin);
   share->db_plugin= NULL;
 
+  /* Release fulltext parsers */
+  key_info= share->key_info;
+  for (idx= share->keys; idx; idx--, key_info++)
+  {
+    if (key_info->flags & HA_USES_PARSER)
+    {
+      plugin_unlock(NULL, key_info->parser);
+      key_info->flags= 0;
+    }
+  }
   /* We must copy mem_root from share because share is allocated through it */
   memcpy((char*) &mem_root, (char*) &share->mem_root, sizeof(mem_root));
   free_root(&mem_root, MYF(0));                 // Free's share
@@ -1943,22 +1955,11 @@ partititon_err:
 int closefrm(register TABLE *table, bool free_share)
 {
   int error=0;
-  uint idx;
-  KEY *key_info;
   DBUG_ENTER("closefrm");
   DBUG_PRINT("enter", ("table: 0x%lx", (long) table));
 
   if (table->db_stat)
     error=table->file->close();
-  key_info= table->key_info;
-  for (idx= table->s->keys; idx; idx--, key_info++)
-  {
-    if (key_info->flags & HA_USES_PARSER)
-    {
-      plugin_unlock(NULL, key_info->parser);
-      key_info->flags= 0;
-    }
-  }
   my_free((char*) table->alias, MYF(MY_ALLOW_ZERO_PTR));
   table->alias= 0;
   if (table->field)