From edd52b4b2865457a47a37465dde4e150879c5c14 Mon Sep 17 00:00:00 2001
From: Ralf Grillenberger <h-a-l-9000@users.sourceforge.net>
Date: Wed, 10 Feb 2010 22:43:01 +0000
Subject: [PATCH] Return the last byte from the serial FIFO buffer in case it
 is empty, not an unrelated one.

Imported-from: https://svn.code.sf.net/p/dosbox/code-0/dosbox/trunk@3547
---
 include/serialport.h | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/include/serialport.h b/include/serialport.h
index 5879a444..64476e1b 100644
--- a/include/serialport.h
+++ b/include/serialport.h
@@ -100,8 +100,9 @@ public:
 	Bit8u getb() {
 		if (!used) return data[pos];
 		Bitu where=pos;
-		if (++pos>=size) pos-=size;
 		used--;
+		if(used) pos++;
+		if (pos>=size) pos-=size;
 		return data[where];
 	}
 	Bit8u getTop() {