Added NzInputStream

Added NzFile::Read(buffer, size)
NzFile::Read(nullptr, size) now acts as a skip function (ex: SetCursorPos(GetCursorPos() + size)

include/Nazara/Core/InputStream.hpp

@@ -0,0 +1,21 @@
+// Copyright (C) 2012 Jérôme Leclercq
+// This file is part of the "Nazara Engine".
+// For conditions of distribution and use, see copyright notice in Config.hpp
+
+#pragma once
+
+#ifndef NAZARA_INPUTSTREAM_HPP
+#define NAZARA_INPUTSTREAM_HPP
+
+#include <Nazara/Prerequesites.hpp>
+
+class NzInputStream
+{
+	public:
+		virtual ~NzInputStream();
+
+		virtual bool EndOfFile() const = 0;
+		virtual std::size_t Read(void* buffer, std::size_t size) = 0;
+};
+
+#endif // NAZARA_INPUTSTREAM_HPP