A wolf attacked me unprovoked.

[Grudvica]

I got out of my hole after the second night, wanted to punch some trees and a Wolf just started growling at me and attacked me. I had Porkchops on me so could that be the reason why it attacked me?

[dawnraider]

It was probably hungry. They don't care about having meat in your inventory, they just attack you when hungry regardless. If they are only hungry (i.e. tail is up and growling, but no texture change), then you can toss meat on the ground for them to eat and that'll pacify them. If they are starving, which can be distinguished by the darker fur similar to when you attack them, then feeding them won't help and you just need to kill them.

[EpicAaron]

Another strange behavior: wolves will become aggressive and actively hunt the player during full moons. They will not change appearance or look angry while doing this. Beware the forest on full moons..

[dawnraider]

The tail is always a way to tell if a wolf is angry or not. I might also look at tweaking textures to make it more obvious because it can still be hard to tell.