Check whether a site has used its allotted upload space.

Determines whether users can self-register, based on Network settings.

Validates a new site sign-up for an existing user.

Validates the new site sign-up.

Validates new site signup.

Deprecated functionality to validate an email address.

Validates user sign-up name and email.

Validates the new user sign-up.

Ensures that the welcome message is not empty. Currently unused.

Activates a signup.