~drizzle-trunk/drizzle/development

/**********************************************************************

Utilities for byte operations

(c) 1994, 1995 Innobase Oy

Created 1/20/1994 Heikki Tuuri

***********************************************************************/

#ifndef ut0byte_h

#define ut0byte_h

#include "univ.i"

/* Type definition for a 64-bit unsigned integer, which works also

in 32-bit machines. NOTE! Access the fields only with the accessor

functions. This definition appears here only for the compiler to

know the size of a dulint. */

typedef	struct dulint_struct	dulint;

struct dulint_struct{

	ulint	high;	/* most significant 32 bits */

	ulint	low;	/* least significant 32 bits */

};

/* Zero value for a dulint */

extern const dulint	ut_dulint_zero;

/* Maximum value for a dulint */

extern const dulint	ut_dulint_max;

/***********************************************************

Creates a 64-bit dulint out of two ulints. */

UNIV_INLINE

dulint

ut_dulint_create(

/*=============*/

			/* out: created dulint */

	ulint	high,	/* in: high-order 32 bits */

	ulint	low);	/* in: low-order 32 bits */

/***********************************************************

Gets the high-order 32 bits of a dulint. */

UNIV_INLINE

ulint

ut_dulint_get_high(

/*===============*/

			/* out: 32 bits in ulint */

	dulint	d);	/* in: dulint */

/***********************************************************

Gets the low-order 32 bits of a dulint. */

UNIV_INLINE

ulint

ut_dulint_get_low(

/*==============*/

			/* out: 32 bits in ulint */

	dulint	d);	/* in: dulint */

/***********************************************************

Converts a dulint (a struct of 2 ulints) to ib_int64_t, which is a 64-bit

integer type. */

UNIV_INLINE

ib_int64_t

ut_conv_dulint_to_longlong(

/*=======================*/

			/* out: value in ib_int64_t type */

	dulint	d);	/* in: dulint */

/***********************************************************

Tests if a dulint is zero. */

UNIV_INLINE

ibool

ut_dulint_is_zero(

/*==============*/

			/* out: TRUE if zero */

	dulint	a);	/* in: dulint */

/***********************************************************

Compares two dulints. */

UNIV_INLINE

int

ut_dulint_cmp(

/*==========*/

			/* out: -1 if a < b, 0 if a == b,

			1 if a > b */

	dulint	a,	/* in: dulint */

	dulint	b);	/* in: dulint */

/***********************************************************

Calculates the max of two dulints. */

UNIV_INLINE

dulint

ut_dulint_get_max(

/*==============*/

			/* out: max(a, b) */

	dulint	a,	/* in: dulint */

	dulint	b);	/* in: dulint */

/***********************************************************

Calculates the min of two dulints. */

UNIV_INLINE

dulint

ut_dulint_get_min(

/*==============*/

			/* out: min(a, b) */

	dulint	a,	/* in: dulint */

	dulint	b);	/* in: dulint */

/***********************************************************

Adds a ulint to a dulint. */

UNIV_INLINE

dulint

ut_dulint_add(

/*==========*/

			/* out: sum a + b */

	dulint	a,	/* in: dulint */

	ulint	b);	/* in: ulint */

/***********************************************************

Subtracts a ulint from a dulint. */

UNIV_INLINE

dulint

ut_dulint_subtract(

/*===============*/

			/* out: a - b */

	dulint	a,	/* in: dulint */

	ulint	b);	/* in: ulint, b <= a */

/***********************************************************

Subtracts a dulint from another. NOTE that the difference must be positive

and smaller that 4G. */

UNIV_INLINE

ulint

ut_dulint_minus(

/*============*/

			/* out: a - b */

	dulint	a,	/* in: dulint; NOTE a must be >= b and at most

			2 to power 32 - 1 greater */

	dulint	b);	/* in: dulint */

/************************************************************

Rounds a dulint downward to a multiple of a power of 2. */

UNIV_INLINE

dulint

ut_dulint_align_down(

/*=================*/

				/* out: rounded value */

	dulint	 n,		/* in: number to be rounded */

	ulint	 align_no);	/* in: align by this number which must be a

				power of 2 */

/************************************************************

Rounds a dulint upward to a multiple of a power of 2. */

UNIV_INLINE

dulint

ut_dulint_align_up(

/*===============*/

				/* out: rounded value */

	dulint	 n,		/* in: number to be rounded */

	ulint	 align_no);	/* in: align by this number which must be a

				power of 2 */

/************************************************************

Rounds a dulint downward to a multiple of a power of 2. */

UNIV_INLINE

ib_uint64_t

ut_uint64_align_down(

/*=================*/

					/* out: rounded value */

	ib_uint64_t	 n,		/* in: number to be rounded */

	ulint		 align_no);	/* in: align by this number

					which must be a power of 2 */

/************************************************************

Rounds ib_uint64_t upward to a multiple of a power of 2. */

UNIV_INLINE

ib_uint64_t

ut_uint64_align_up(

/*===============*/

					/* out: rounded value */

	ib_uint64_t	 n,		/* in: number to be rounded */

	ulint		 align_no);	/* in: align by this number

					which must be a power of 2 */

/***********************************************************

Increments a dulint variable by 1. */

#define UT_DULINT_INC(D)\

{\

	if ((D).low == 0xFFFFFFFFUL) {\

		(D).high = (D).high + 1;\

		(D).low = 0;\

	} else {\

		(D).low = (D).low + 1;\

	}\

}

/***********************************************************

Tests if two dulints are equal. */

#define UT_DULINT_EQ(D1, D2)	(((D1).low == (D2).low)\

						&& ((D1).high == (D2).high))

#ifdef notdefined

/****************************************************************

Sort function for dulint arrays. */

UNIV_INTERN

void

ut_dulint_sort(dulint* arr, dulint* aux_arr, ulint low, ulint high);

/*===============================================================*/

#endif /* notdefined */

/*************************************************************

The following function rounds up a pointer to the nearest aligned address. */

UNIV_INLINE

void*

ut_align(

/*=====*/

				/* out: aligned pointer */

	void*	ptr,		/* in: pointer */

	ulint	align_no);	/* in: align by this number */

/*************************************************************

The following function rounds down a pointer to the nearest

aligned address. */

UNIV_INLINE

void*

ut_align_down(

/*==========*/

					/* out: aligned pointer */

	const void*	ptr,		/* in: pointer */

	ulint		align_no)	/* in: align by this number */

		__attribute__((__const__));

/*************************************************************

The following function computes the offset of a pointer from the nearest

aligned address. */

UNIV_INLINE

ulint

ut_align_offset(

/*============*/

					/* out: distance from aligned

					pointer */

	const void*	ptr,		/* in: pointer */

	ulint		align_no)	/* in: align by this number */

			__attribute__((__const__));

/*********************************************************************

Gets the nth bit of a ulint. */

UNIV_INLINE

ibool

ut_bit_get_nth(

/*===========*/

			/* out: TRUE if nth bit is 1; 0th bit is defined to

			be the least significant */

	ulint	a,	/* in: ulint */

	ulint	n);	/* in: nth bit requested */

/*********************************************************************

Sets the nth bit of a ulint. */

UNIV_INLINE

ulint

ut_bit_set_nth(

/*===========*/

			/* out: the ulint with the bit set as requested */

	ulint	a,	/* in: ulint */

	ulint	n,	/* in: nth bit requested */

	ibool	val);	/* in: value for the bit to set */

#ifndef UNIV_NONINL

#include "ut0byte.ic"

#endif

#endif