openjpeg/libopenjpeg/int.h

/*
 * Copyright (c) 2002-2007, Communications and Remote Sensing Laboratory, Universite catholique de Louvain (UCL), Belgium
 * Copyright (c) 2002-2007, Professor Benoit Macq
 * Copyright (c) 2001-2003, David Janssens
 * Copyright (c) 2002-2003, Yannick Verschueren
 * Copyright (c) 2003-2007, Francois-Olivier Devaux and Antonin Descampe
 * Copyright (c) 2005, Herve Drolon, FreeImage Team
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS `AS IS'
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */
#ifndef __INT_H
#define __INT_H
/**
@file int.h
@brief Implementation of operations on integers (INT)

The functions in INT.H have for goal to realize operations on integers.
*/

/** @defgroup INT INT - Implementation of operations on integers */
/*@{*/

/** @name Exported functions (see also openjpeg.h) */
/*@{*/
/* ----------------------------------------------------------------------- */

#include <assert.h>

#ifdef HAVE_STDINT_H
#include <stdint.h>
#else
#if defined(_WIN32)
typedef   signed __int8   int8_t;
typedef unsigned __int8   uint8_t;
typedef   signed __int16  int16_t;
typedef unsigned __int16  uint16_t;
typedef   signed __int32  int32_t;
typedef unsigned __int32  uint32_t;
typedef   signed __int64  int64_t;
typedef unsigned __int64  uint64_t;
#else
#error unsupported platform
#endif
#endif

/**
Get the minimum of two integers
@return Returns a if a < b else b
*/
static INLINE int int_min(int a, int b) {
	return a < b ? a : b;
}
/**
Get the maximum of two integers
@return Returns a if a > b else b
*/
static INLINE int int_max(int a, int b) {
	return (a > b) ? a : b;
}
/**
Clamp an integer inside an interval
@return
<ul>
<li>Returns a if (min < a < max)
<li>Returns max if (a > max)
<li>Returns min if (a < min) 
</ul>
*/
static INLINE int int_clamp(int a, int min, int max) {
	if (a < min)
		return min;
	if (a > max)
		return max;
	return a;
}
/**
@return Get absolute value of integer
*/
static INLINE int int_abs(int a) {
	return a < 0 ? -a : a;
}
/**
Divide an integer and round upwards
@return Returns a divided by b
*/
static INLINE int int_ceildiv(int a, int b) {
    assert(b);
    return (a + b - 1) / b;
}

/**
Divide an integer by a power of 2 and round upwards
@return Returns a divided by 2^b
*/
static INLINE int int_ceildivpow2(int a, int b) {
    return (int)((a + (int64_t)(1 << b) - 1) >> b);
}
/**
Divide an integer by a power of 2 and round downwards
@return Returns a divided by 2^b
*/
static INLINE int int_floordivpow2(int a, int b) {
	return a >> b;
}
/**
Get logarithm of an integer and round downwards
@return Returns log2(a)
*/
static INLINE int int_floorlog2(int a) {
	int l;
	for (l = 0; a > 1; l++) {
		a >>= 1;
	}
	return l;
}
/* ----------------------------------------------------------------------- */
/*@}*/

/*@}*/

#endif