Show Room Occupancy Based On Dates

I want to a create a formula that reviews a series of start dates and end date, then sums the number of days (if the end and start date are withing a yearly period). i.e.

Column A = Room No
Column B = Start dates
Column C = End dates

Column A references a list of rooms (Room List)
If Column A = Room123
If start date is equal to or greater than 31/12/2007
If end date is less than or equal to 31/12/2008
Calculate the number of days used.