List of fields of a specific type

I am writing a CCK field module and need to access a list of fields, filtered by a specific field type. Is there a function available within CCK that can do this? I am not interested in the node types, purely the field types.

I know I can use the following SQL:
SELECT `field_name` FROM `node_field` WHERE `type` = 'text'
to return a list of all the fields of type 'text'. But I don't like to use SQL in my code if there is already a function available to do this.