mirror of
https://github.com/reactos/reactos.git
synced 2024-08-22 11:22:59 +00:00
74 lines
1.4 KiB
C
74 lines
1.4 KiB
C
#include <precomp.h>
|
|
|
|
|
|
/*
|
|
* Convert a unicode string to an unsigned long integer.
|
|
*
|
|
* Ignores `locale' stuff. Assumes that the upper and lower case
|
|
* alphabets and digits are each contiguous.
|
|
*
|
|
* @implemented
|
|
*/
|
|
unsigned long
|
|
CDECL
|
|
wcstoul(const wchar_t *nptr, wchar_t **endptr, int base)
|
|
{
|
|
const wchar_t *s = nptr;
|
|
unsigned long acc;
|
|
int c;
|
|
unsigned long cutoff;
|
|
int neg = 0, any, cutlim;
|
|
|
|
/*
|
|
* See strtol for comments as to the logic used.
|
|
*/
|
|
do {
|
|
c = *s++;
|
|
} while (iswctype(c, _SPACE));
|
|
if (c == L'-')
|
|
{
|
|
neg = 1;
|
|
c = *s++;
|
|
}
|
|
else if (c == L'+')
|
|
c = *s++;
|
|
if ((base == 0 || base == 16) &&
|
|
c == L'0' && (*s == L'x' || *s == L'X'))
|
|
{
|
|
c = s[1];
|
|
s += 2;
|
|
base = 16;
|
|
}
|
|
if (base == 0)
|
|
base = c == L'0' ? 8 : 10;
|
|
cutoff = (unsigned long)ULONG_MAX / (unsigned long)base;
|
|
cutlim = (unsigned long)ULONG_MAX % (unsigned long)base;
|
|
for (acc = 0, any = 0;; c = *s++)
|
|
{
|
|
if (iswctype(c, _DIGIT))
|
|
c -= L'0';
|
|
else if (iswctype(c, _ALPHA))
|
|
c -= iswctype(c, _UPPER) ? L'A' - 10 : L'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 = ULONG_MAX;
|
|
}
|
|
else if (neg)
|
|
acc = 0-acc;
|
|
if (endptr != 0)
|
|
*endptr = any ? (wchar_t *)((size_t)(s - 1)) : (wchar_t *)((size_t)nptr);
|
|
return acc;
|
|
}
|