mes/lib/m2/ntoab.c

70 lines
1.5 KiB
C

/* -*-comment-start: "//";comment-end:""-*-
* GNU Mes --- Maxwell Equations of Software
* Copyright © 2016,2017,2018,2019,2020 Jan (janneke) Nieuwenhuizen <janneke@gnu.org>
*
* This file is part of GNU Mes.
*
* GNU Mes is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 3 of the License, or (at
* your option) any later version.
*
* GNU Mes is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GNU Mes. If not, see <http://www.gnu.org/licenses/>.
*/
#include <mes/lib.h>
#include <assert.h>
#include <string.h>
char *__itoa_buf;
char *
ntoab (long x, int base, int signed_p)
{
if (__itoa_buf == 0)
__itoa_buf = malloc (20);
char *buf = __itoa_buf;
char *p = buf + 11;
p[0] = 0;
p = p - 1;
assert_msg (base > 0, "base > 0");
int sign_p = 0;
unsigned u;
unsigned i;
if (signed_p != 0 && x < 0)
{
sign_p = 1;
u = -x;
}
else
u = x;
do
{
i = u % base;
u = u / base;
if (i > 9)
p[0] = 'a' + i - 10;
else
p[0] = '0' + i;
p = p - 1;
}
while (u != 0);
if (sign_p && p[1] != '0')
{
p[0] = '-';
p = p - 1;
}
return p + 1;
}