Added exception class for general warnings, separate from the one for fatal errors.

src/emucore/exception/EmulationWarning.hxx

@@ -0,0 +1,38 @@
+//============================================================================
+//
+//   SSSS    tt          lll  lll
+//  SS  SS   tt           ll   ll
+//  SS     tttttt  eeee   ll   ll   aaaa
+//   SSSS    tt   ee  ee  ll   ll      aa
+//      SS   tt   eeeeee  ll   ll   aaaaa  --  "An Atari 2600 VCS Emulator"
+//  SS  SS   tt   ee      ll   ll  aa  aa
+//   SSSS     ttt  eeeee llll llll  aaaaa
+//
+// Copyright (c) 1995-2018 by Bradford W. Mott, Stephen Anthony
+// and the Stella Team
+//
+// See the file "License.txt" for information on usage and redistribution of
+// this file, and for a DISCLAIMER OF ALL WARRANTIES.
+//============================================================================
+
+#ifndef EMULATION_WARNING_HXX
+#define EMULATION_WARNING_HXX
+
+#include "bspf.hxx"
+
+class EmulationWarning : public std::exception
+{
+  public:
+    EmulationWarning(const string& message) : myMessage(message) { }
+
+    const char* what() const noexcept override { return myMessage.c_str(); }
+
+    [[noreturn]] static void raise(const string& message) {
+      throw EmulationWarning(message);
+    }
+
+  private:
+    const string myMessage;
+};
+
+#endif // EMULATION_WARNING_HXX