Fix for bug#24219 ALTER TABLE ... RENAME TO ... , DISABLE KEYS leads to crash

(this is the 5.0 patch, because 4.1 differs)
  
There was an improper order of doing chained operations.
  
To the documentor: ENABLE|DISABLE KEYS combined with RENAME TO, and no other
ALTER TABLE clause, leads to server crash independent of the presence of
indices and data in the table.


mysql-test/r/alter_table.result:
  post-merge fix
  my locale is utf8, and this breaks non-utf8 stuff when doing manual merge :(
sql/sql_table.cc:
  If there is operation on the KEYS, first do it
  and then do a rename if there is such. Or, we will crash because
  the underlying table has changed.

1 files changed, 28 insertions, 23 deletions

diff --git a/sql/sql_table.cc b/sql/sql_table.cc
index c76ebe7ef49..e7e08837b65 100644
--- a/sql/sql_table.cc
+++ b/sql/sql_table.cc
@@ -3300,13 +3300,35 @@ view_err:
   if (!(alter_info->flags & ~(ALTER_RENAME | ALTER_KEYS_ONOFF)) &&
       !table->s->tmp_table) // no need to touch frm
   {
-    error=0;
     VOID(pthread_mutex_lock(&LOCK_open));
-    if (new_name != table_name || new_db != db)
+
+    switch (alter_info->keys_onoff) {
+    case LEAVE_AS_IS:
+      error= 0;
+      break;
+    case ENABLE:
+      wait_while_table_is_used(thd, table, HA_EXTRA_FORCE_REOPEN);
+      error= table->file->enable_indexes(HA_KEY_SWITCH_NONUNIQ_SAVE);
+      /* COND_refresh will be signaled in close_thread_tables() */
+      break;
+    case DISABLE:
+      wait_while_table_is_used(thd, table, HA_EXTRA_FORCE_REOPEN);
+      error=table->file->disable_indexes(HA_KEY_SWITCH_NONUNIQ_SAVE);
+      /* COND_refresh will be signaled in close_thread_tables() */
+      break;
+    }
+    if (error == HA_ERR_WRONG_COMMAND)
+    {
+      push_warning_printf(thd, MYSQL_ERROR::WARN_LEVEL_NOTE,
+			  ER_ILLEGAL_HA, ER(ER_ILLEGAL_HA),
+			  table->alias);
+      error= 0;
+    }
+
+    if (!error && (new_name != table_name || new_db != db))
     {
       thd->proc_info="rename";
       /* Then do a 'simple' rename of the table */
-      error=0;
       if (!access(new_name_buff,F_OK))
       {
 	my_error(ER_TABLE_EXISTS_ERROR, MYF(0), new_name);
@@ -3328,31 +3350,14 @@ view_err:
       }
     }
 
-    if (!error)
-    {
-      switch (alter_info->keys_onoff) {
-      case LEAVE_AS_IS:
-        break;
-      case ENABLE:
-        wait_while_table_is_used(thd, table, HA_EXTRA_FORCE_REOPEN);
-        error= table->file->enable_indexes(HA_KEY_SWITCH_NONUNIQ_SAVE);
-        /* COND_refresh will be signaled in close_thread_tables() */
-        break;
-      case DISABLE:
-        wait_while_table_is_used(thd, table, HA_EXTRA_FORCE_REOPEN);
-        error=table->file->disable_indexes(HA_KEY_SWITCH_NONUNIQ_SAVE);
-        /* COND_refresh will be signaled in close_thread_tables() */
-        break;
-      }
-    }
-
     if (error == HA_ERR_WRONG_COMMAND)
     {
       push_warning_printf(thd, MYSQL_ERROR::WARN_LEVEL_NOTE,
 			  ER_ILLEGAL_HA, ER(ER_ILLEGAL_HA),
 			  table->alias);
-      error=0;
+      error= 0;
     }
+
     if (!error)
     {
       if (mysql_bin_log.is_open())
@@ -3370,7 +3375,7 @@ view_err:
       error= -1;
     }
     VOID(pthread_mutex_unlock(&LOCK_open));
-    table_list->table=0;				// For query cache
+    table_list->table= NULL;                    // For query cache
     query_cache_invalidate3(thd, table_list, 0);
     DBUG_RETURN(error);
   }