mirror of
https://github.com/cryb-to/cryb-to.git
synced 2024-11-15 02:05:40 +00:00
67 lines
2.1 KiB
C
67 lines
2.1 KiB
C
/*
|
|
* Copyright (c) 2017 Dag-Erling Smørgrav
|
|
* 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.
|
|
* 3. The name of the author may not be used to endorse or promote
|
|
* products derived from this software without specific prior written
|
|
* permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
|
|
*/
|
|
|
|
#include "cryb/impl.h"
|
|
|
|
#include <stddef.h>
|
|
#include <stdint.h>
|
|
#include <strings.h>
|
|
|
|
#include <cryb/bitwise.h>
|
|
#include <cryb/mpi.h>
|
|
|
|
#include "cryb_mpi_impl.h"
|
|
|
|
/*
|
|
* Increment X in place.
|
|
*/
|
|
int
|
|
mpi_inc_abs(cryb_mpi *X)
|
|
{
|
|
unsigned int i;
|
|
|
|
/* trivial case: zero */
|
|
if (X->msb == 0) {
|
|
X->words[0] = 1;
|
|
X->msb = 1;
|
|
return (0);
|
|
}
|
|
|
|
/* may grow by 1 bit */
|
|
if (mpi_grow(X, X->msb + 1) != 0)
|
|
return (-1);
|
|
|
|
/* increment least-significant word and propagate */
|
|
for (i = 0; ++X->words[i] == 0; ++i)
|
|
/* nothing */;
|
|
i = X->msb / 32;
|
|
X->msb = i * 32 + flsl(X->words[i]);
|
|
|
|
return (0);
|
|
}
|