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/* -*-comment-start: "//";comment-end:""-*-
* GNU Mes --- Maxwell Equations of Software
* Copyright © 2017,2018 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 <stdlib.h>
#include <stdio.h>
#include <string.h>
#define memset xmemset
#define calloc xcalloc
void *
memset (void *s, int c, size_t n)
{
char *p = s;
while (n--)
*p++ = c;
return s;
}
void *
calloc (size_t nmemb, size_t size)
{
size_t count = nmemb * size;
void *p = malloc (count);
memset (p, 0, count);
return p;
}
/* {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'} */
char little_endian_table[16] =
{ 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46 };
char *
little_endian (unsigned value, char *c, int number_of_bytes)
{
char table[16] =
{ 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46 };
switch (number_of_bytes)
{
case 4:
{
c[6] = table[value >> 28];
c[7] = table[(value >> 24) % 16];
}
case 3:
{
c[4] = table[(value >> 20) % 16];
c[5] = table[(value >> 16) % 16];
}
case 2:
{
c[2] = table[(value >> 12) % 16];
c[3] = table[(value >> 8) % 16];
}
case 1:
{
c[0] = table[(value >> 4) % 16];
c[1] = table[value % 16];
break;
}
default:
return "invalid";
}
return c;
}
int
main ()
{
char table[3] = { '0', '1', '2' };
char *s;
s = calloc (10, sizeof (char));
eputs ("2=");
eputs (little_endian (2, s, 1));
eputs ("\n");
if (strcmp (s, "02"))
return 1;
eputs ("8=");
eputs (little_endian (8, s, 2));
eputs ("\n");
if (strcmp (s, "0800"))
return 2;
eputs ("16=");
eputs (little_endian (16, s, 4));
eputs ("\n");
if (strcmp (s, "10000000"))
return 3;
return 0;
}
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