redirect all wildcard subdomains to root domain

In my case I need rule like foo.bar.com > bar.com/page/foo and I found in apache documentation this:

RewriteCond %{HTTP_HOST} ^(.+)\.bar\.com$ [NC]
RewriteCond %{HTTP_HOST} !www.bar.com$ [NC]
RewriteRule ^(.*)$ http://bar.com/page/%1/$1 [L,R=301]

Use a RewriteCond to match domains other than mydomain.com and 301 redirect them:

RewriteEngine On
# If the domain (any domain) is not exactly mydomain.com...
RewriteCond %{HTTP_HOST} !^mydomain\.com$ [NC]
RewriteRule (.*) http://mydomain.com/$1 [L,R=301,QSA]

You can also look more specifically for subdomains of mydomain.com. The one above would match any other domain.

# Match only subdomains of mydomain.com
RewriteCond %{HTTP_HOST} ^(.+)\.mydomain\.com$ [NC]
RewriteRule (.*) http://mydomain.com/$1 [L,R=301,QSA]