// Copyright (c) 1996-2009 Nokia Corporation and/or its subsidiary(-ies).
// All rights reserved.
// This component and the accompanying materials are made available
// under the terms of "Eclipse Public License v1.0"
// which accompanies this distribution, and is available
// at the URL "http://www.eclipse.org/legal/epl-v10.html".
//
// Initial Contributors:
// Nokia Corporation - initial contribution.
//
// Contributors:
//
// Description:
//

typedef unsigned char  BYTE;	// TUint8
typedef unsigned short WORD;	// TUint16
typedef unsigned int   UINT;	// TUint

#include <string.h>
#include <e32std.h>
#include <e32std_private.h>
#include "e32uid.h"

const UINT crcTab[256] =
    {
	0x0000,0x1021,0x2042,0x3063,0x4084,0x50a5,0x60c6,0x70e7,0x8108,0x9129,0xa14a,
	0xb16b,0xc18c,0xd1ad,0xe1ce,0xf1ef,0x1231,0x0210,0x3273,0x2252,0x52b5,0x4294,
	0x72f7,0x62d6,0x9339,0x8318,0xb37b,0xa35a,0xd3bd,0xc39c,0xf3ff,0xe3de,0x2462,
	0x3443,0x0420,0x1401,0x64e6,0x74c7,0x44a4,0x5485,0xa56a,0xb54b,0x8528,0x9509,
	0xe5ee,0xf5cf,0xc5ac,0xd58d,0x3653,0x2672,0x1611,0x0630,0x76d7,0x66f6,0x5695,
	0x46b4,0xb75b,0xa77a,0x9719,0x8738,0xf7df,0xe7fe,0xd79d,0xc7bc,0x48c4,0x58e5,
	0x6886,0x78a7,0x0840,0x1861,0x2802,0x3823,0xc9cc,0xd9ed,0xe98e,0xf9af,0x8948,
	0x9969,0xa90a,0xb92b,0x5af5,0x4ad4,0x7ab7,0x6a96,0x1a71,0x0a50,0x3a33,0x2a12,
	0xdbfd,0xcbdc,0xfbbf,0xeb9e,0x9b79,0x8b58,0xbb3b,0xab1a,0x6ca6,0x7c87,0x4ce4,
	0x5cc5,0x2c22,0x3c03,0x0c60,0x1c41,0xedae,0xfd8f,0xcdec,0xddcd,0xad2a,0xbd0b,
	0x8d68,0x9d49,0x7e97,0x6eb6,0x5ed5,0x4ef4,0x3e13,0x2e32,0x1e51,0x0e70,0xff9f,
	0xefbe,0xdfdd,0xcffc,0xbf1b,0xaf3a,0x9f59,0x8f78,0x9188,0x81a9,0xb1ca,0xa1eb,
	0xd10c,0xc12d,0xf14e,0xe16f,0x1080,0x00a1,0x30c2,0x20e3,0x5004,0x4025,0x7046,
	0x6067,0x83b9,0x9398,0xa3fb,0xb3da,0xc33d,0xd31c,0xe37f,0xf35e,0x02b1,0x1290,
	0x22f3,0x32d2,0x4235,0x5214,0x6277,0x7256,0xb5ea,0xa5cb,0x95a8,0x8589,0xf56e,
	0xe54f,0xd52c,0xc50d,0x34e2,0x24c3,0x14a0,0x0481,0x7466,0x6447,0x5424,0x4405,
	0xa7db,0xb7fa,0x8799,0x97b8,0xe75f,0xf77e,0xc71d,0xd73c,0x26d3,0x36f2,0x0691,
	0x16b0,0x6657,0x7676,0x4615,0x5634,0xd94c,0xc96d,0xf90e,0xe92f,0x99c8,0x89e9,
	0xb98a,0xa9ab,0x5844,0x4865,0x7806,0x6827,0x18c0,0x08e1,0x3882,0x28a3,0xcb7d,
	0xdb5c,0xeb3f,0xfb1e,0x8bf9,0x9bd8,0xabbb,0xbb9a,0x4a75,0x5a54,0x6a37,0x7a16,
	0x0af1,0x1ad0,0x2ab3,0x3a92,0xfd2e,0xed0f,0xdd6c,0xcd4d,0xbdaa,0xad8b,0x9de8,
	0x8dc9,0x7c26,0x6c07,0x5c64,0x4c45,0x3ca2,0x2c83,0x1ce0,0x0cc1,0xef1f,0xff3e,
	0xcf5d,0xdf7c,0xaf9b,0xbfba,0x8fd9,0x9ff8,0x6e17,0x7e36,0x4e55,0x5e74,0x2e93,
	0x3eb2,0x0ed1,0x1ef0
    };

void Crc(WORD& aCrc,const void* aPtr,int aLength)
//
// Perform a CCITT CRC checksum.
//
	{

	const BYTE* pB=(const BYTE*)aPtr;
	const BYTE* pE=pB+aLength;
	UINT crc=aCrc;
    while (pB<pE)
		crc=(crc<<8)^crcTab[((crc>>8)^*pB++)&0xff];
	aCrc=(WORD)crc;
	}

UINT checkSum(const void* aPtr)
//
// Checksum every other byte
//
	{

	const BYTE* pB=(const BYTE*)aPtr;
	const BYTE* pE=pB+(KMaxCheckedUid*sizeof(TUid));
	BYTE buf[(KMaxCheckedUid*sizeof(TUid))>>1];
	BYTE* pT=(&buf[0]);
	while (pB<pE)
		{
		*pT++=(*pB);
		pB+=2;
		}
	WORD crc=0;
	Crc(crc,&buf[0],(KMaxCheckedUid*sizeof(TUid))>>1);
	return(crc);
	}
	
int TUid::operator==(const TUid& aUid) const
//
// Compare UID's for equality
//
	{

	return(iUid==aUid.iUid);
	}

int TUid::operator!=(const TUid& aUid) const
//
// Compare UID's for equality
//
	{

	return(iUid!=aUid.iUid);
	}

TUidType::TUidType()
//
// Constructor
//
    {

	memset(this,0,sizeof(TUidType));
    }

TUidType::TUidType(TUid aUid1)
//
// Constructor
//
    {


	memset(this,0,sizeof(TUidType));
    iUid[0]=aUid1;
    }

TUidType::TUidType(TUid aUid1,TUid aUid2)
//
// Constructor
//
    {

    iUid[0]=aUid1;
    iUid[1]=aUid2;
    iUid[2]=KNullUid;
    }

TUidType::TUidType(TUid aUid1,TUid aUid2,TUid aUid3)
//
// Constructor
//
    {


    iUid[0]=aUid1;
    iUid[1]=aUid2;
    iUid[2]=aUid3;
    }

int TUidType::operator==(const TUidType& aUidType) const
//
// TRUE if equal.
//
    {

    return(iUid[0]==aUidType.iUid[0] &&
           iUid[1]==aUidType.iUid[1] &&
           iUid[2]==aUidType.iUid[2]);
    }

int TUidType::operator!=(const TUidType& aUidType) const
//
// TRUE if not equal.
//
    {


    return(!(*this==aUidType));
    }

const TUid& TUidType::operator[](int anIndex) const
//
// Array operator.
//
    {

	return(iUid[anIndex]);
    }

TUid TUidType::MostDerived() const
//
// Return the most derived type
//
    {

    if (iUid[2]!=KNullUid)
        return(iUid[2]);
    if (iUid[1]!=KNullUid)
        return(iUid[1]);
    return(iUid[0]);
    }

int TUidType::IsPresent(TUid aUid) const
//
// TRUE if aUid is present as any type.
//
    {

	return(iUid[0]==aUid || iUid[1]==aUid || iUid[2]==aUid);
    }

int TUidType::IsValid() const
//
// TRUE if one of the type is not NULL.
//
    {

    return(MostDerived()!=KNullUid);
    }

TCheckedUid::TCheckedUid()
//
// Constructor
//
	{

	memset(this,0,sizeof(TCheckedUid));
	}

TCheckedUid::TCheckedUid(const TUidType& aUidType)
//
// Constructor
//
	{

    Set(aUidType);
    }

void TCheckedUid::Set(const TUidType& aUidType)
//
// Set from a aUidType
//
	{

    iType=aUidType;
    iCheck=Check();
    }

UINT TCheckedUid::Check() const
//
// Return the checksum of the UIDs
//
	{

	return((checkSum(((BYTE*)this)+1)<<16)|checkSum((BYTE*)this));
	}