Changed database, tablename and alias to be LEX_CSTRING

This was done in, among other things:
- thd->db and thd->db_length
- TABLE_LIST tablename, db, alias and schema_name
- Audit plugin database name
- lex->db
- All db and table names in Alter_table_ctx
- st_select_lex db

Other things:
- Changed a lot of functions to take const LEX_CSTRING* as argument
  for db, table_name and alias. See init_one_table() as an example.
- Changed some function arguments from LEX_CSTRING to const LEX_CSTRING
- Changed some lists from LEX_STRING to LEX_CSTRING
- threads_mysql.result changed because process list_db wasn't always
  correctly updated
- New append_identifier() function that takes LEX_CSTRING* as arguments
- Added new element tmp_buff to Alter_table_ctx to separate temp name
  handling from temporary space
- Ensure we store the length after my_casedn_str() of table/db names
- Removed not used version of rename_table_in_stat_tables()
- Changed Natural_join_column::table_name and db_name() to never return
  NULL (used for print)
- thd->get_db() now returns db as a printable string (thd->db.str or "")

1 files changed, 4 insertions, 8 deletions

diff --git a/sql/rpl_gtid.cc b/sql/rpl_gtid.cc
index 78e6165a551..1b176d10b4c 100644
--- a/sql/rpl_gtid.cc
+++ b/sql/rpl_gtid.cc
@@ -28,8 +28,8 @@
 #include "slave.h"
 #include "log_event.h"
 
-const LEX_STRING rpl_gtid_slave_state_table_name=
-  { C_STRING_WITH_LEN("gtid_slave_pos") };
+const LEX_CSTRING rpl_gtid_slave_state_table_name=
+  { STRING_WITH_LEN("gtid_slave_pos") };
 
 
 void
@@ -401,10 +401,7 @@ rpl_slave_state::truncate_state_table(THD *thd)
   int err= 0;
 
   tmp_disable_binlog(thd);
-  tlist.init_one_table(STRING_WITH_LEN("mysql"),
-                       rpl_gtid_slave_state_table_name.str,
-                       rpl_gtid_slave_state_table_name.length,
-                       NULL, TL_WRITE);
+  tlist.init_one_table(&MYSQL_SCHEMA_NAME, &rpl_gtid_slave_state_table_name, NULL, TL_WRITE);
   if (!(err= open_and_lock_tables(thd, &tlist, FALSE, 0)))
   {
     err= tlist.table->file->ha_truncate();
@@ -655,8 +652,7 @@ rpl_slave_state::record_gtid(THD *thd, const rpl_gtid *gtid, uint64 sub_id,
   */
   suspended_wfc= thd->suspend_subsequent_commits();
   thd->lex->reset_n_backup_query_tables_list(&lex_backup);
-  tlist.init_one_table(STRING_WITH_LEN("mysql"), gtid_pos_table_name.str,
-                       gtid_pos_table_name.length, NULL, TL_WRITE);
+  tlist.init_one_table(&MYSQL_SCHEMA_NAME, &gtid_pos_table_name, NULL, TL_WRITE);
   if ((err= open_and_lock_tables(thd, &tlist, FALSE, 0)))
     goto end;
   table_opened= true;