MDEV-5535: Cannot reopen temporary table

mysqld maintains a list of TABLE objects for all temporary
tables created within a session in THD. Here each table is
represented by a TABLE object.

A query referencing a particular temporary table for more
than once, however, failed with ER_CANT_REOPEN_TABLE error
because a TABLE_SHARE was allocate together with the TABLE,
so temporary tables always had only one TABLE per TABLE_SHARE.

This patch lift this restriction by separating TABLE and
TABLE_SHARE objects and storing TABLE_SHAREs for temporary
tables in a list in THD, and TABLEs in a list within their
respective TABLE_SHAREs.

1 files changed, 41 insertions, 10 deletions

diff --git a/sql/rpl_rli.cc b/sql/rpl_rli.cc
index f9d0910a2a7..f8f06d613f4 100644
--- a/sql/rpl_rli.cc
+++ b/sql/rpl_rli.cc
@@ -1,5 +1,6 @@
 /* Copyright (c) 2006, 2013, Oracle and/or its affiliates.
    Copyright (c) 2010, 2013, Monty Program Ab
+   Copyright (c) 2016, MariaDB Corporation
 
    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
@@ -52,8 +53,8 @@ Relay_log_info::Relay_log_info(bool is_slave_recovery)
    no_storage(FALSE), replicate_same_server_id(::replicate_same_server_id),
    info_fd(-1), cur_log_fd(-1), relay_log(&sync_relaylog_period),
    sync_counter(0), is_relay_log_recovery(is_slave_recovery),
-   save_temporary_tables(0), mi(0),
-   inuse_relaylog_list(0), last_inuse_relaylog(0),
+   save_temporary_tables(0),
+   mi(0), inuse_relaylog_list(0), last_inuse_relaylog(0),
    cur_log_old_open_count(0), group_relay_log_pos(0), 
    event_relay_log_pos(0),
 #if HAVE_valgrind
@@ -1062,24 +1063,53 @@ void Relay_log_info::inc_group_relay_log_pos(ulonglong log_pos,
 
 void Relay_log_info::close_temporary_tables()
 {
-  TABLE *table,*next;
   DBUG_ENTER("Relay_log_info::close_temporary_tables");
 
-  for (table=save_temporary_tables ; table ; table=next)
+  TMP_TABLE_SHARE *share;
+  TABLE *table;
+
+  if (!save_temporary_tables)
   {
-    next=table->next;
+    /* There are no temporary tables. */
+    DBUG_VOID_RETURN;
+  }
+
+  while ((share= save_temporary_tables->pop_front()))
+  {
+    /*
+      Iterate over the list of tables for this TABLE_SHARE and close them.
+    */
+    while ((table= share->all_tmp_tables.pop_front()))
+    {
+      DBUG_PRINT("tmptable", ("closing table: '%s'.'%s'",
+                              table->s->db.str, table->s->table_name.str));
+
+      /* Reset in_use as the table may have been created by another thd */
+      table->in_use= 0;
+      /*
+        Lets not free TABLE_SHARE here as there could be multiple TABLEs opened
+        for the same table (TABLE_SHARE).
+      */
+      closefrm(table);
+      my_free(table);
+    }
 
-    /* Reset in_use as the table may have been created by another thd */
-    table->in_use=0;
     /*
       Don't ask for disk deletion. For now, anyway they will be deleted when
       slave restarts, but it is a better intention to not delete them.
     */
-    DBUG_PRINT("info", ("table: 0x%lx", (long) table));
-    close_temporary(table, 1, 0);
+
+    free_table_share(share);
+    my_free(share);
   }
-  save_temporary_tables= 0;
+
+  /* By now, there mustn't be any elements left in the list. */
+  DBUG_ASSERT(save_temporary_tables->is_empty());
+
+  my_free(save_temporary_tables);
+  save_temporary_tables= NULL;
   slave_open_temp_tables= 0;
+
   DBUG_VOID_RETURN;
 }
 
@@ -1756,6 +1786,7 @@ void rpl_group_info::cleanup_context(THD *thd, bool error)
   }
   m_table_map.clear_tables();
   slave_close_thread_tables(thd);
+
   if (error)
   {
     thd->mdl_context.release_transactional_locks();