Non veni pacem mittere, sed gladium.
Considering the age of the building, looks safe enough to me. I have seen this before on you tube. There are diverters built on the rock to channel water to a catch basin.
Really! That's genius.
Certainly safe from hailstorms!
Incidentally, that post isn't to hold the stove pipe; it's what's holding up the rock. ;-)
This should be part of your "Cabin Porn" series.