[Maria-discuss] mariadb : possible copyright issues?

I am using MySQL at present. I came across MariaDB, a drop-in replacement for MySQL. 2 simple questions-- 1) File names in MariaDB, in many cases, are same as those in MySQL. Wouldn't that attract objection from Oracle as 'breach of the copyright' ? 2) May I use MariaDB for commercial distribution (with or without using its source) ? Whether the license is similar to MIT license? Thanks, Vineet