Mozilla/mozilla/js/tamarin/shell/DataIO.h

/* ***** BEGIN LICENSE BLOCK ***** 
 * Version: MPL 1.1/GPL 2.0/LGPL 2.1 
 *
 * The contents of this file are subject to the Mozilla Public License Version 1.1 (the 
 * "License"); you may not use this file except in compliance with the License. You may obtain 
 * a copy of the License at http://www.mozilla.org/MPL/ 
 * 
 * Software distributed under the License is distributed on an "AS IS" basis, WITHOUT 
 * WARRANTY OF ANY KIND, either express or implied. See the License for the specific 
 * language governing rights and limitations under the License. 
 * 
 * The Original Code is [Open Source Virtual Machine.] 
 * 
 * The Initial Developer of the Original Code is Adobe System Incorporated.  Portions created 
 * by the Initial Developer are Copyright (C)[ 2004-2006 ] Adobe Systems Incorporated. All Rights 
 * Reserved. 
 * 
 * Contributor(s): Adobe AS3 Team
 * 
 * Alternatively, the contents of this file may be used under the terms of either the GNU 
 * General Public License Version 2 or later (the "GPL"), or the GNU Lesser General Public 
 * License Version 2.1 or later (the "LGPL"), in which case the provisions of the GPL or the 
 * LGPL are applicable instead of those above. If you wish to allow use of your version of this 
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 * version of this file under the terms of the MPL, indicate your decision by deleting provisions 
 * above and replace them with the notice and other provisions required by the GPL or the 
 * LGPL. If you do not delete the provisions above, a recipient may use your version of this file 
 * under the terms of any one of the MPL, the GPL or the LGPL. 
 * 
 ***** END LICENSE BLOCK ***** */


#ifndef DATAIO_INCLUDED
#define DATAIO_INCLUDED

namespace avmshell
{
	template <class T>
	inline void CoreSwap(T& a, T& b)
	{
		T t = a;
		a = b;
		b = t;
	}

	inline void FlipU16(uint16& value)
	{
		uint8 *pa = (uint8 *)&(value);
		CoreSwap(pa[0], pa[1]);
	}

	inline void FlipU64(uint64& value)
	{
		uint8 *pa = (uint8 *)&(value);
		CoreSwap(pa[0], pa[7]);
		CoreSwap(pa[1], pa[6]);
		CoreSwap(pa[2], pa[5]);
		CoreSwap(pa[3], pa[4]);
	}

	inline void FlipU32(uint32& value)
	{
		uint8 *pa = (uint8 *)&(value);
		CoreSwap(pa[0], pa[3]);
		CoreSwap(pa[1], pa[2]);
	}

	enum ObjectEncoding {
		kAMF0 = 0,
		kAMF3 = 3,
		kEncodeDefault = kAMF3	
	};

	enum Endian
	{
		kBigEndian    = 0,
		kLittleEndian = 1
	};

	class DataIOBase
	{
	public:
		DataIOBase() { m_endian = kBigEndian; }

		virtual ~DataIOBase()
		{ 
			m_endian = kBigEndian;
		}
		
		
		Endian GetEndian() const { return m_endian; }
		void SetEndian(Endian endian) { m_endian = endian; }

		void ConvertU16(uint16& value)
		{
			if (GetEndian() != GetNativeEndian())
			{
				FlipU16(value);
			}
		}
		
		void ConvertU32(uint32& value)
		{
			if (GetEndian() != GetNativeEndian())
			{
				FlipU32(value);
			}
		}
		
		void ConvertU64(uint64& value)
		{
			if (GetEndian() != GetNativeEndian())
			{
				FlipU64(value);
			}
		}			

		Endian GetNativeEndian() const
		{
			#ifdef WIN32
			return kLittleEndian;
			#else
			return kBigEndian;
			#endif
		}
			
	private:
		Endian m_endian;
	};
		
	typedef unsigned char U8;

	class DataInput : virtual public DataIOBase
	{
	public:
		DataInput(Toplevel *toplevel) : m_toplevel(toplevel) {}
				
		virtual uint32 Available() = 0;
		virtual void Read(void *buffer, uint32 count) = 0;
		
		bool ReadBoolean();
		U8 ReadU8();
		unsigned short ReadU16();
		uint32 ReadU32();
		float ReadFloat();
		double ReadDouble();
		String* ReadUTF();
		String* ReadUTFBytes(uint32 length);
		void ReadByteArray(ByteArray& buffer, uint32 offset, uint32 count);

	protected:
		// FIXME: make const
		DRC(Toplevel *) m_toplevel;

		void ThrowEOFError();
		void ThrowMemoryError();
		void CheckEOF(uint32 count);
	};

	class DataOutput : virtual public DataIOBase
	{
	public:
		DataOutput(Toplevel *toplevel) : m_toplevel(toplevel) { }

		virtual void Write(const void *buffer, uint32 count) = 0;

		void WriteBoolean(bool value);
		void WriteU8(U8 value);
		void WriteU16(unsigned short value);
		void WriteU32(uint32 value);
		void WriteFloat(float value);
		void WriteDouble(double value);
		void WriteUTF(String *str);
		void WriteUTFBytes(String *str);
		void WriteByteArray(ByteArray& buffer, uint32 offset, uint32 count);

	protected:
		// FIXME: make const
		DRC(Toplevel *) m_toplevel;

		void ThrowRangeError();

	};
}	

#endif /* DATAIO_INCLUDED */