install_import_translations in core/includes/
Imports languages via a batch process during installation.
install_select_language_form in core/includes/
Form constructor for the language selection form.
language_admin_add_predefined_form_submit in core/modules/language/
Process the predefined language addition form submission.
language_admin_predefined_list in core/modules/language/
Prepare a language code list for unused predefined languages.
language_save in core/modules/language/language.module
API function to add or update a language.
language_update_1003 in core/modules/language/language.install
Add the native name to all enabled languages.
locale_translate_import_form_submit in core/modules/locale/
Process the locale import form submission.