#ifndef CRYPTOPP_MISC_H
#define CRYPTOPP_MISC_H

#include "cryptlib.h"
#include "smartptr.h"

#ifdef INTEL_INTRINSICS
#include <stdlib.h>
#endif

NAMESPACE_BEGIN(CryptoPP)

// ************** compile-time assertion ***************

template <bool b>
struct CompileAssert
{
	static char dummy[2*b-1];
};

#define CRYPTOPP_COMPILE_ASSERT(assertion) CRYPTOPP_COMPILE_ASSERT_INSTANCE(assertion, __LINE__)
#if defined(CRYPTOPP_EXPORTS) || defined(CRYPTOPP_IMPORTS)
#define CRYPTOPP_COMPILE_ASSERT_INSTANCE(assertion, instance)
#else
#define CRYPTOPP_COMPILE_ASSERT_INSTANCE(assertion, instance) static CompileAssert<(assertion)> CRYPTOPP_ASSERT_JOIN(cryptopp_assert_, instance)
#endif
#define CRYPTOPP_ASSERT_JOIN(X, Y) CRYPTOPP_DO_ASSERT_JOIN(X, Y)
#define CRYPTOPP_DO_ASSERT_JOIN(X, Y) X##Y

// ************** misc classes ***************

class CRYPTOPP_DLL Empty
{
};

//! _
template <class BASE1, class BASE2>
class CRYPTOPP_NO_VTABLE TwoBases : public BASE1, public BASE2
{
};

//! _
template <class BASE1, class BASE2, class BASE3>
class CRYPTOPP_NO_VTABLE ThreeBases : public BASE1, public BASE2, public BASE3
{
};

template <class T>
class ObjectHolder
{
protected:
	T m_object;
};

class NotCopyable
{
public:
	NotCopyable() {}
private:
    NotCopyable(const NotCopyable &);
    void operator=(const NotCopyable &);
};

template <class T>
struct NewObject
{
	T* operator()() const {return new T;}
};

/*! This function safely initializes a static object in a multithreaded environment without using locks.
	It may leak memory when two threads try to initialize the static object at the same time
	but this should be acceptable since each static object is only initialized once per session.
*/
template <class T, class F = NewObject<T>, int instance=0>
class Singleton
{
public:
	Singleton(F objectFactory = F()) : m_objectFactory(objectFactory) {}

	// VC60 workaround: use "..." to prevent this function from being inlined
	const T & Ref(...) const;

private:
	F m_objectFactory;
};

template <class T, class F, int instance>
const T & Singleton<T, F, instance>::Ref(...) const
{
	static simple_ptr<T> s_pObject;
	static char s_objectState = 0;

retry:
	switch (s_objectState)
	{
	case 0:
		s_objectState = 1;
		try
		{
			s_pObject.m_p = m_objectFactory();
		}
		catch(...)
		{
			s_objectState = 0;
			throw;
		}
		s_objectState = 2;
		break;
	case 1:
		goto retry;
	default:
		break;
	}
	return *s_pObject.m_p;
}

// ************** misc functions ***************

// can't use std::min or std::max in MSVC60 or Cygwin 1.1.0
template <class T> inline const T& STDMIN(const T& a, const T& b)
{
	return b < a ? b : a;
}

template <class T> inline const T& STDMAX(const T& a, const T& b)
{
	return a < b ? b : a;
}

#define RETURN_IF_NONZERO(x) unsigned int returnedValue = x; if (returnedValue) return returnedValue

// this version of the macro is fastest on Pentium 3 and Pentium 4 with MSVC 6 SP5 w/ Processor Pack
#define GETBYTE(x, y) (unsigned int)byte((x)>>(8*(y)))
// these may be faster on other CPUs/compilers
// #define GETBYTE(x, y) (unsigned int)(((x)>>(8*(y)))&255)
// #define GETBYTE(x, y) (((byte *)&(x))[y])

CRYPTOPP_DLL unsigned int Parity(unsigned long);
CRYPTOPP_DLL unsigned int BytePrecision(unsigned long);
CRYPTOPP_DLL unsigned int BitPrecision(unsigned long);
CRYPTOPP_DLL unsigned long Crop(unsigned long, unsigned int size);

inline unsigned int BitsToBytes(unsigned int bitCount)
{
	return ((bitCount+7)/(8));
}

inline unsigned int BytesToWords(unsigned int byteCount)
{
	return ((byteCount+WORD_SIZE-1)/WORD_SIZE);
}

inline unsigned int BitsToWords(unsigned int bitCount)
{
	return ((bitCount+WORD_BITS-1)/(WORD_BITS));
}

inline unsigned int BitsToDwords(unsigned int bitCount)
{
	return ((bitCount+2*WORD_BITS-1)/(2*WORD_BITS));
}

CRYPTOPP_DLL void xorbuf(byte *buf, const byte *mask, unsigned int count);
CRYPTOPP_DLL void xorbuf(byte *output, const byte *input, const byte *mask, unsigned int count);

template <class T>
inline bool IsPowerOf2(T n)
{
	return n > 0 && (n & (n-1)) == 0;
}

template <class T1, class T2>
inline T2 ModPowerOf2(T1 a, T2 b)
{
	assert(IsPowerOf2(b));
	return T2(a) & (b-1);
}

template <class T>
inline T RoundDownToMultipleOf(T n, T m)
{
	return n - (IsPowerOf2(m) ? ModPowerOf2(n, m) : (n%m));
}

template <class T>
inline T RoundUpToMultipleOf(T n, T m)
{
	return RoundDownToMultipleOf(n+m-1, m);
}

template <class T>
inline unsigned int GetAlignment(T *dummy=NULL)	// VC60 workaround
{
#if (_MSC_VER >= 1300)
	return __alignof(T);
#elif defined(__GNUC__)
	return __alignof__(T);
#else
	return sizeof(T);
#endif
}

inline bool IsAlignedOn(const void *p, unsigned int alignment)
{
	return IsPowerOf2(alignment) ? ModPowerOf2((size_t)p, alignment) == 0 : (size_t)p % alignment == 0;
}

template <class T>
inline bool IsAligned(const void *p, T *dummy=NULL)	// VC60 workaround
{
	return IsAlignedOn(p, GetAlignment<T>());
}

#ifdef IS_LITTLE_ENDIAN
	typedef LittleEndian NativeByteOrder;
#else
	typedef BigEndian NativeByteOrder;
#endif

inline ByteOrder GetNativeByteOrder()
{
	return NativeByteOrder::ToEnum();
}

inline bool NativeByteOrderIs(ByteOrder order)
{
	return order == GetNativeByteOrder();
}

template <class T>		// can't use <sstream> because GCC 2.95.2 doesn't have it
std::string IntToString(T a, unsigned int base = 10)
{
	if (a == 0)
		return "0";
	bool negate = false;
	if (a < 0)
	{
		negate = true;
		a = 0-a;	// VC .NET does not like -a
	}
	std::string result;
	while (a > 0)
	{
		T digit = a % base;
		result = char((digit < 10 ? '0' : ('a' - 10)) + digit) + result;
		a /= base;
	}
	if (negate)
		result = "-" + result;
	return result;
}

template <class T1, class T2>
inline T1 SaturatingSubtract(T1 a, T2 b)
{
	CRYPTOPP_COMPILE_ASSERT_INSTANCE(T1(-1)>0, 0);	// T1 is unsigned type
	CRYPTOPP_COMPILE_ASSERT_INSTANCE(T2(-1)>0, 1);	// T2 is unsigned type
	return T1((a > b) ? (a - b) : 0);
}

template <class T>
inline CipherDir GetCipherDir(const T &obj)
{
	return obj.IsForwardTransformation() ? ENCRYPTION : DECRYPTION;
}

void CallNewHandler();

// ************** rotate functions ***************

template <class T> inline T rotlFixed(T x, unsigned int y)
{
	assert(y < sizeof(T)*8);
	return (x<<y) | (x>>(sizeof(T)*8-y));
}

template <class T> inline T rotrFixed(T x, unsigned int y)
{
	assert(y < sizeof(T)*8);
	return (x>>y) | (x<<(sizeof(T)*8-y));
}

template <class T> inline T rotlVariable(T x, unsigned int y)
{
	assert(y < sizeof(T)*8);
	return (x<<y) | (x>>(sizeof(T)*8-y));
}

template <class T> inline T rotrVariable(T x, unsigned int y)
{
	assert(y < sizeof(T)*8);
	return (x>>y) | (x<<(sizeof(T)*8-y));
}

template <class T> inline T rotlMod(T x, unsigned int y)
{
	y %= sizeof(T)*8;
	return (x<<y) | (x>>(sizeof(T)*8-y));
}

template <class T> inline T rotrMod(T x, unsigned int y)
{
	y %= sizeof(T)*8;
	return (x>>y) | (x<<(sizeof(T)*8-y));
}

#ifdef INTEL_INTRINSICS

#pragma intrinsic(_lrotl, _lrotr)

template<> inline word32 rotlFixed<word32>(word32 x, unsigned int y)
{
	assert(y < 32);
	return y ? _lrotl(x, y) : x;
}

template<> inline word32 rotrFixed<word32>(word32 x, unsigned int y)
{
	assert(y < 32);
	return y ? _lrotr(x, y) : x;
}

template<> inline word32 rotlVariable<word32>(word32 x, unsigned int y)
{
	assert(y < 32);
	return _lrotl(x, y);
}

template<> inline word32 rotrVariable<word32>(word32 x, unsigned int y)
{
	assert(y < 32);
	return _lrotr(x, y);
}

template<> inline word32 rotlMod<word32>(word32 x, unsigned int y)
{
	return _lrotl(x, y);
}

template<> inline word32 rotrMod<word32>(word32 x, unsigned int y)
{
	return _lrotr(x, y);
}

#endif // #ifdef INTEL_INTRINSICS

#ifdef PPC_INTRINSICS

template<> inline word32 rotlFixed<word32>(word32 x, unsigned int y)
{
	assert(y < 32);
	return y ? __rlwinm(x,y,0,31) : x;
}

template<> inline word32 rotrFixed<word32>(word32 x, unsigned int y)
{
	assert(y < 32);
	return y ? __rlwinm(x,32-y,0,31) : x;
}

template<> inline word32 rotlVariable<word32>(word32 x, unsigned int y)
{
	assert(y < 32);
	return (__rlwnm(x,y,0,31));
}

template<> inline word32 rotrVariable<word32>(word32 x, unsigned int y)
{
	assert(y < 32);
	return (__rlwnm(x,32-y,0,31));
}

template<> inline word32 rotlMod<word32>(word32 x, unsigned int y)
{
	return (__rlwnm(x,y,0,31));
}

template<> inline word32 rotrMod<word32>(word32 x, unsigned int y)
{
	return (__rlwnm(x,32-y,0,31));
}

#endif // #ifdef PPC_INTRINSICS

// ************** endian reversal ***************

template <class T>
inline unsigned int GetByte(ByteOrder order, T value, unsigned int index)
{
	if (order == LITTLE_ENDIAN_ORDER)
		return GETBYTE(value, index);
	else
		return GETBYTE(value, sizeof(T)-index-1);
}

inline byte ByteReverse(byte value)
{
	return value;
}

inline word16 ByteReverse(word16 value)
{
	return rotlFixed(value, 8U);
}

inline word32 ByteReverse(word32 value)
{
#ifdef PPC_INTRINSICS