openjpeg/libopenjpeg/int.c

114 lines
2.5 KiB
C

/*
* Copyright (c) 2001-2002, David Janssens
* 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.
*/
/*
* Get the minimum of two integers.
*
* returns a if a < b else b
*/
int int_min(int a, int b)
{
return a < b ? a : b;
}
/*
* Get the maximum of two integers.
*
* returns a if a > b else b
*/
int int_max(int a, int b)
{
return a > b ? a : b;
}
/*
* Clamp an integer inside an interval.
*
* return a if (min < a < max)
* return max if (a > max)
* return min if (a < min)
*/
int int_clamp(int a, int min, int max)
{
if (a < min)
return min;
if (a > max)
return max;
return a;
}
/*
* Get absolute value of integer.
*/
int int_abs(int a)
{
return a < 0 ? -a : a;
}
/*
* Divide an integer and round upwards.
*
* a divided by b
*/
int int_ceildiv(int a, int b)
{
return (a + b - 1) / b;
}
/*
* Divide an integer by a power of 2 and round upwards.
*
* a divided by 2^b
*/
int int_ceildivpow2(int a, int b)
{
return (a + (1 << b) - 1) >> b;
}
/*
* Divide an integer by a power of 2 and round downwards.
*
* a divided by 2^b
*/
int int_floordivpow2(int a, int b)
{
return a >> b;
}
/*
* Get logarithm of an integer and round downwards.
*
* log2(a)
*/
int int_floorlog2(int a)
{
int l;
for (l = 0; a > 1; l++) {
a >>= 1;
}
return l;
}