Re-implemented the NullSound back-end. Allows Dolphin to be used on hosts with no sound hardware. Emulates strict DSP timing in the DSP HLE plugin.

git-svn-id: https://dolphin-emu.googlecode.com/svn/trunk@6329 8ced0084-cf51-0410-be5f-012b33b47a6e

Source/Core/AudioCommon/Src/NullSoundStream.cpp

@@ -0,0 +1,48 @@
+// Copyright (C) 2003 Dolphin Project.
+
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, version 2.0.
+
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License 2.0 for more details.
+
+// A copy of the GPL 2.0 should have been included with the program.
+// If not, see http://www.gnu.org/licenses/
+
+// Official SVN repository and contact information can be found at
+// http://code.google.com/p/dolphin-emu/
+
+#include "AudioCommon.h"
+#include "NullSoundStream.h"
+
+void NullSound::SoundLoop()
+{
+}
+
+bool NullSound::Start()
+{
+	return true;
+}
+
+void NullSound::SetVolume(int volume)
+{
+}
+
+void NullSound::Update()
+{
+	// This should equal AUDIO_DMA_PERIOD.  TODO: Fix after DSP merge
+	int numBytesToRender = 32000 * 4 / 32;
+	m_mixer->Mix(realtimeBuffer, numBytesToRender / 4);
+}
+
+void NullSound::Clear(bool mute)
+{
+	m_muted = mute;
+}
+
+void NullSound::Stop()
+{
+}