From 7a452cbf72a0ea6038d87ad16d5ab6ac08f64756 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Sebastian=20Strohh=C3=A4cker?=
 <c2woody@users.sourceforge.net>
Date: Wed, 16 Aug 2006 16:08:24 +0000
Subject: [PATCH] prevent rare crashes when forcing sb16 when no second dma
 controller is present

Imported-from: https://svn.code.sf.net/p/dosbox/code-0/dosbox/trunk@2686
---
 src/hardware/sblaster.cpp | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/src/hardware/sblaster.cpp b/src/hardware/sblaster.cpp
index 561df6a1..dd2efd4b 100644
--- a/src/hardware/sblaster.cpp
+++ b/src/hardware/sblaster.cpp
@@ -16,7 +16,7 @@
  *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  */
 
-/* $Id: sblaster.cpp,v 1.54 2006-06-29 19:05:54 qbix79 Exp $ */
+/* $Id: sblaster.cpp,v 1.55 2006-08-16 16:08:24 c2woody Exp $ */
 
 #include <string.h>
 #include <math.h> 
@@ -591,8 +591,14 @@ static void DSP_PrepareDMA_New(DMA_MODES mode,Bitu length,bool autoinit,bool ste
 	sb.dma.total=length;
 	sb.dma.autoinit=autoinit;
 	if (mode==DSP_DMA_16) {
-		if (sb.hw.dma16!=0xff) sb.dma.chan=GetDMAChannel(sb.hw.dma16);
-		else {
+		if (sb.hw.dma16!=0xff) {
+			sb.dma.chan=GetDMAChannel(sb.hw.dma16);
+			if (sb.dma.chan==NULL) {
+				sb.dma.chan=GetDMAChannel(sb.hw.dma8);
+				mode=DSP_DMA_16_ALIASED;
+				freq/=2;
+			}
+		} else {
 			sb.dma.chan=GetDMAChannel(sb.hw.dma8);
 			mode=DSP_DMA_16_ALIASED;
 			freq/=2;