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/*
* Copyright (c) 2008 Nicira Networks.
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#ifndef SAT_MATH_H
#define SAT_MATH_H 1
#include <assert.h>
#include <limits.h>
/* Saturating addition: overflow yields UINT_MAX. */
static inline unsigned int
sat_add(unsigned int x, unsigned int y)
{
return x + y >= x ? x + y : UINT_MAX;
}
/* Saturating subtraction: underflow yields 0. */
static inline unsigned int
sat_sub(unsigned int x, unsigned int y)
{
return x >= y ? x - y : 0;
}
/* Saturating multiplication: overflow yields UINT_MAX. */
static inline unsigned int
sat_mul(unsigned int x, unsigned int y)
{
return (!y ? 0
: x <= UINT_MAX / y ? x * y
: UINT_MAX);
}
#endif /* sat-math.h */
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