SharpCompressArchiveHandler: throw fewer exceptions

BizHawk.Client.Common/SharpCompressArchiveHandler.cs

@@ -25,12 +25,22 @@ namespace BizHawk.Client.Common
 		{
 			_archive?.Dispose();
 			_archive = null;
-		}
+		}
+
+		/// <summary>
+		/// whitelist extensions, to avoid thrown exceptions
+		/// </summary>
+		public string[] ArchiveExtensions = { ".zip", ".gz", ".gzip", ".tar", ".rar", ".7z" };
 
 		public bool CheckSignature(string fileName, out int offset, out bool isExecutable)
 		{
 			offset = 0;
 			isExecutable = false;
+			
+			var pathExt = Path.GetExtension(fileName).ToLower();
+			if (!ArchiveExtensions.Contains(pathExt))
+				return false;
+
 			try
 			{
 				using (var arcTest = ArchiveFactory.Open(fileName))

BizHawk.Common/HawkFile.cs

@@ -440,7 +440,8 @@ namespace BizHawk.Common
 			int offset;
 			bool isExecutable;
 
-			if (NonArchiveExtensions.Any(ext => Path.GetExtension(path).ToLower() == ext.ToLower()))
+			var pathExt = Path.GetExtension(path).ToLower();
+			if (NonArchiveExtensions.Contains(pathExt))
 			{
 				return;
 			}