All of a sudden I developed a problem where when I press the brake pedal it goes to the floor (with about half its normal resistance) and I hear what sounds like a constant rather loud leak of air up front. My rear brakes work fine but the fronts seem to be disabled by whatever problem this might be. My brake fluid is not leaking at all.

Bad master cylinder, or maybe something simpler? Never had this kind of problem.

 

If the pedal is going to the floor, the mater cyl is more than likely done for and needs to be replaced. Please do not drive until this issue is addressed.

 

Turns out it was the brake booster that went bad. Just in case anyone stumbles across this thread.