From 7bda44277218dabec1a5f89ef5497a43d5d2a3b3 Mon Sep 17 00:00:00 2001
From: Denneisk <20892685+Denneisk@users.noreply.github.com>
Date: Mon, 13 Nov 2023 20:04:16 -0500
Subject: [PATCH] Mitigate nil addition in EGP.umsg.End

---
 .../gmod_wire_egp/lib/egplib/umsgsystem.lua       | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/lua/entities/gmod_wire_egp/lib/egplib/umsgsystem.lua b/lua/entities/gmod_wire_egp/lib/egplib/umsgsystem.lua
index 01c7989cd6..32ff5791d4 100644
--- a/lua/entities/gmod_wire_egp/lib/egplib/umsgsystem.lua
+++ b/lua/entities/gmod_wire_egp/lib/egplib/umsgsystem.lua
@@ -3,7 +3,7 @@
 --------------------------------------------------------
 local EGP = EGP
 
-local CurSender
+local CurSender = NULL
 local LastErrorTime = 0
 --[[ Transmit Sizes:
 	Angle = 12
@@ -21,7 +21,7 @@ local LastErrorTime = 0
 EGP.umsg = {}
 
 function EGP.umsg.Start( name, sender )
-	if CurSender then
+	if CurSender:IsValid() then
 		if (LastErrorTime + 1 < CurTime()) then
 			ErrorNoHalt("[EGP] Umsg error. It seems another umsg is already sending, but it occured over 1 second ago. Ending umsg.")
 			EGP.umsg.End()
@@ -40,10 +40,15 @@ function EGP.umsg.Start( name, sender )
 end
 
 function EGP.umsg.End()
-	if CurSender then
+	if CurSender:IsValid() then
 		if not EGP.IntervalCheck[CurSender] then EGP.IntervalCheck[CurSender] = { bytes = 0, time = 0 } end
-		EGP.IntervalCheck[CurSender].bytes = EGP.IntervalCheck[CurSender].bytes + net.BytesWritten()
+		local bytes = net.BytesWritten()
+		if bytes then
+			EGP.IntervalCheck[CurSender].bytes = EGP.IntervalCheck[CurSender].bytes + bytes
+		else
+			ErrorNoHalt("Tried to end EGP net message outside of net context?")
+		end
 	end
 	net.Broadcast()
-	CurSender = nil
+	CurSender = NULL
 end