89 lines
2.3 KiB
C
89 lines
2.3 KiB
C
/*
|
|
* convert from ASCII form of unsigned long to binary
|
|
* Copyright (C) 1998, 1999 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"
|
|
|
|
/*
|
|
- atoul - convert ASCII substring to unsigned long number
|
|
*/
|
|
const char * /* NULL for success, else string literal */
|
|
atoul(src, srclen, base, resultp)
|
|
const char *src;
|
|
size_t srclen; /* 0 means strlen(src) */
|
|
int base; /* 0 means figure it out */
|
|
unsigned long *resultp;
|
|
{
|
|
const char *stop;
|
|
static char hex[] = "0123456789abcdef";
|
|
static char uchex[] = "0123456789ABCDEF";
|
|
int d;
|
|
char c;
|
|
char *p;
|
|
unsigned long r;
|
|
unsigned long rlimit;
|
|
int dlimit;
|
|
|
|
if (srclen == 0)
|
|
srclen = strlen(src);
|
|
if (srclen == 0)
|
|
return "empty string";
|
|
|
|
if (base == 0 || base == 13) {
|
|
if (srclen > 2 && *src == '0' && CIEQ(*(src+1), 'x'))
|
|
return atoul(src+2, srclen-2, 16, resultp);
|
|
if (srclen > 1 && *src == '0' && base != 13)
|
|
return atoul(src+1, srclen-1, 8, resultp);
|
|
return atoul(src, srclen, 10, resultp);
|
|
}
|
|
if (base != 8 && base != 10 && base != 16)
|
|
return "unsupported number base";
|
|
|
|
r = 0;
|
|
stop = src + srclen;
|
|
if (base == 16) {
|
|
while (src < stop) {
|
|
c = *src++;
|
|
p = strchr(hex, c);
|
|
if (p != NULL)
|
|
d = p - hex;
|
|
else {
|
|
p = strchr(uchex, c);
|
|
if (p == NULL)
|
|
return "non-hex-digit in hex number";
|
|
d = p - uchex;
|
|
}
|
|
r = (r << 4) | d;
|
|
}
|
|
/* defer length check to catch invalid digits first */
|
|
if (srclen > sizeof(unsigned long) * 2)
|
|
return "hex number too long";
|
|
} else {
|
|
rlimit = ULONG_MAX / base;
|
|
dlimit = (int)(ULONG_MAX - rlimit*base);
|
|
while (src < stop) {
|
|
c = *src++;
|
|
d = c - '0';
|
|
if (d < 0 || d >= base)
|
|
return "non-digit in number";
|
|
if (r > rlimit || (r == rlimit && d > dlimit))
|
|
return "unsigned-long overflow";
|
|
r = r*base + d;
|
|
}
|
|
}
|
|
|
|
*resultp = r;
|
|
return NULL;
|
|
}
|