Hmm...  Looks like a unified diff to me...
The text leading up to this was:
--------------------------
|diff -up dwm/dwm.c dwmmod/dwm.c
|--- dwm/dwm.c	2020-06-25 00:21:30.383692180 -0300
|+++ dwmmod/dwm.c	2020-06-25 00:20:35.643692330 -0300
--------------------------
Patching file dwm.c using Plan A...
Hunk #1 succeeded at 1057.
done