[OMPT-svn-commit] OpenMPT r20650 - trunk/OpenMPT/soundlib

[<sv...@op...>]

Author: sagamusix
Date: Mon Apr 22 23:01:04 2024
New Revision: 20650
URL: https://source.openmpt.org/browse/openmpt/?op=revision&rev=20650

Log:
[Fix] MIDI macro command s didn't compute correct checksum if a device ID was made up from two bytes (e.g. XV-5080).

Modified:
   trunk/OpenMPT/soundlib/Snd_fx.cpp

Modified: trunk/OpenMPT/soundlib/Snd_fx.cpp
==============================================================================
--- trunk/OpenMPT/soundlib/Snd_fx.cpp	Mon Apr 22 22:50:56 2024	(r20649)
+++ trunk/OpenMPT/soundlib/Snd_fx.cpp	Mon Apr 22 23:01:04 2024	(r20650)
@@ -5173,12 +5173,17 @@
 		{
 			// SysEx Checksum (not an original Impulse Tracker macro variable, but added for convenience)
 			auto startPos = outPos;
-			while(startPos > 0 && out[--startPos] != 0xF0);
-			if(outPos - startPos < 5 || out[startPos] != 0xF0)
-			{
+			while(startPos > 0 && out[--startPos] != 0xF0)
+				;
+
+			if(outPos - startPos < 3 || out[startPos] != 0xF0)
 				continue;
-			}
-			for(auto p = startPos + 5u; p != outPos; p++)
+
+			uint8 checksumStart = out[startPos + 3] ? 5 : 6;
+			if(outPos - startPos < checksumStart)
+				continue;
+
+			for(auto p = startPos + checksumStart; p != outPos; p++)
 			{
 				data += out[p];
 			}