strongswan/src/libfreeswan/ultot.c

82 lines
1.7 KiB
C

/*
* convert unsigned long to text
* Copyright (C) 2000 Henry Spencer.
*
* This library is free software; you can redistribute it and/or modify it
* under the terms of the GNU Library General Public License as published by
* the Free Software Foundation; either version 2 of the License, or (at your
* option) any later version. See <http://www.fsf.org/copyleft/lgpl.txt>.
*
* This library 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 Library General Public
* License for more details.
*/
#include "internal.h"
#include "freeswan.h"
/*
- ultot - convert unsigned long to text
*/
size_t /* length required for full conversion */
ultot(n, base, dst, dstlen)
unsigned long n;
int base;
char *dst; /* need not be valid if dstlen is 0 */
size_t dstlen;
{
char buf[3*sizeof(unsigned long) + 1];
char *bufend = buf + sizeof(buf);
size_t len;
char *p;
static char hex[] = "0123456789abcdef";
# define HEX32 (32/4)
p = bufend;
*--p = '\0';
switch (base) {
case 10:
case 'd':
do {
*--p = n%10 + '0';
n /= 10;
} while (n != 0);
break;
case 16:
case 17:
case 'x':
do {
*--p = hex[n&0xf];
n >>= 4;
} while (n != 0);
if (base == 17)
while (bufend - p < HEX32 + 1)
*--p = '0';
if (base == 'x') {
*--p = 'x';
*--p = '0';
}
break;
case 8:
case 'o':
do {
*--p = (n&07) + '0';
n >>= 3;
} while (n != 0);
if (base == 'o')
*--p = '0';
break;
default:
return 0;
break;
}
len = bufend - p;
if (dstlen > 0) {
if (len > dstlen)
*(p + dstlen - 1) = '\0';
strcpy(dst, p);
}
return len;
}