Hmm...  Looks like a unified diff to me...
The text leading up to this was:
--------------------------
|From cbaa365a336355712e3c63a550f903b2cd46ab58 Mon Sep 17 00:00:00 2001
|From: Anton Yabchinskiy <arn@bestmx.net>
|Date: Sun, 1 Oct 2023 22:42:59 +0300
|Subject: [PATCH] Add setxkbgroup() function to be used in keys[]
|
|---
| dwm.c | 17 +++++++++++++++++
| 1 file changed, 17 insertions(+)
|
|diff --git a/dwm.c b/dwm.c
|index e5efb6a2..4a6632f3 100644
|--- a/dwm.c
|+++ b/dwm.c
--------------------------
Patching file dwm.c using Plan A...
Hunk #1 succeeded at 36.
Hunk #2 succeeded at 235.
Hunk #3 succeeded at 2124.
Hmm...  Ignoring the trailing garbage.
done