Ios: How can i restrict my game in landscape mode only?

Hello,
My game is in landscape mode and i want to add feature to upload photo from gallery.
But due to new iOS update its only available in portrait mode.
or it should be enable with other device orientation.
So if we do that then game will work in 3 orientation i.e. Portrait, landscape-left, landscape-right
So is it possible that by editing some cocos2d-x code portrait mode can be ignored?
:pensive: