mirror of
https://github.com/reactos/reactos.git
synced 2024-07-07 13:15:07 +00:00
68 lines
1.3 KiB
C
68 lines
1.3 KiB
C
#include <precomp.h>
|
|
|
|
unsigned long long
|
|
CDECL
|
|
strtoull(const char *nptr, char **endptr, int base)
|
|
{
|
|
const char *s = nptr;
|
|
unsigned long long acc;
|
|
int c;
|
|
unsigned long long cutoff;
|
|
int neg = 0, any, cutlim;
|
|
|
|
/*
|
|
* See strtol for comments as to the logic used.
|
|
*/
|
|
do {
|
|
c = *s++;
|
|
} while (isspace(c));
|
|
if (c == '-')
|
|
{
|
|
neg = 1;
|
|
c = *s++;
|
|
}
|
|
else if (c == '+')
|
|
c = *s++;
|
|
if ((base == 0 || base == 16) &&
|
|
c == '0' && (*s == 'x' || *s == 'X'))
|
|
{
|
|
c = s[1];
|
|
s += 2;
|
|
base = 16;
|
|
}
|
|
if (base == 0)
|
|
base = c == '0' ? 8 : 10;
|
|
cutoff = (unsigned long long)ULLONG_MAX / (unsigned long long)base;
|
|
cutlim = (unsigned long long)ULLONG_MAX % (unsigned long long)base;
|
|
for (acc = 0, any = 0;; c = *s++)
|
|
{
|
|
if (isdigit(c))
|
|
c -= '0';
|
|
else if (isalpha(c))
|
|
c -= isupper(c) ? 'A' - 10 : 'a' - 10;
|
|
else
|
|
break;
|
|
if (c >= base)
|
|
break;
|
|
if (any < 0 || acc > cutoff || (acc == cutoff && c > cutlim))
|
|
any = -1;
|
|
else {
|
|
any = 1;
|
|
acc *= base;
|
|
acc += c;
|
|
}
|
|
}
|
|
if (any < 0)
|
|
{
|
|
acc = ULLONG_MAX;
|
|
#ifndef _LIBCNT_
|
|
_set_errno(ERANGE);
|
|
#endif
|
|
}
|
|
else if (neg)
|
|
acc = 0-acc;
|
|
if (endptr != 0)
|
|
*endptr = any ? (char *)((size_t)(s - 1)) : (char *)((size_t)nptr);
|
|
return acc;
|
|
}
|