Hmm...  Looks like a unified diff to me...
The text leading up to this was:
--------------------------
|From 9ec1210a82b137014de4644ba65be5e53398e281 Mon Sep 17 00:00:00 2001
|From: Jack Bird <jack.bird@durham.ac.uk>
|Date: Wed, 21 Jul 2021 16:43:06 +0100
|Subject: [PATCH] Updated leftlayout for 138b405
|
|---
| dwm.c | 31 +++++++++++++++++--------------
| 1 file changed, 17 insertions(+), 14 deletions(-)
|
|diff --git a/dwm.c b/dwm.c
|index 5e4d494..a5a3980 100644
|--- a/dwm.c
|+++ b/dwm.c
--------------------------
Patching file dwm.c using Plan A...
Hunk #1 succeeded at 432.
Hunk #2 succeeded at 718.
Hunk #3 succeeded at 731.
Hmm...  Ignoring the trailing garbage.
done