ReactOS 0.4.15-dev-7889-g76290a6
wcstoul.c
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1#include <precomp.h>
2
3
4/*
5 * Convert a unicode string to an unsigned long integer.
6 *
7 * Ignores `locale' stuff. Assumes that the upper and lower case
8 * alphabets and digits are each contiguous.
9 *
10 * @implemented
11 */
12unsigned long
14wcstoul(const wchar_t *nptr, wchar_t **endptr, int base)
15{
16 const wchar_t *s = nptr;
17 unsigned long acc;
18 int c;
19 unsigned long cutoff;
20 int neg = 0, any, cutlim;
21
22 /*
23 * See strtol for comments as to the logic used.
24 */
25 do {
26 c = *s++;
27 } while (iswctype(c, _SPACE));
28 if (c == L'-')
29 {
30 neg = 1;
31 c = *s++;
32 }
33 else if (c == L'+')
34 c = *s++;
35 if ((base == 0 || base == 16) &&
36 c == L'0' && (*s == L'x' || *s == L'X'))
37 {
38 c = s[1];
39 s += 2;
40 base = 16;
41 }
42 if (base == 0)
43 base = c == L'0' ? 8 : 10;
44 cutoff = (unsigned long)ULONG_MAX / (unsigned long)base;
45 cutlim = (unsigned long)ULONG_MAX % (unsigned long)base;
46 for (acc = 0, any = 0;; c = *s++)
47 {
48 if (iswctype(c, _DIGIT))
49 c -= L'0';
50 else if (iswctype(c, _ALPHA))
51 c -= iswctype(c, _UPPER) ? L'A' - 10 : L'a' - 10;
52 else
53 break;
54 if (c >= base)
55 break;
56 if (any < 0 || acc > cutoff || (acc == cutoff && c > cutlim))
57 any = -1;
58 else {
59 any = 1;
60 acc *= base;
61 acc += c;
62 }
63 }
64 if (any < 0)
65 {
66 acc = ULONG_MAX;
67 }
68 else if (neg)
69 acc = 0-acc;
70 if (endptr != 0)
71 *endptr = any ? (wchar_t *)((size_t)(s - 1)) : (wchar_t *)((size_t)nptr);
72 return acc;
73}
#define CDECL
Definition: compat.h:29
int __cdecl iswctype(wint_t wc, wctype_t wctypeFlags)
Definition: freeldr.c:99
GLdouble s
Definition: gl.h:2039
const GLubyte * c
Definition: glext.h:8905
#define _SPACE
Definition: ctype.h:68
#define _ALPHA
Definition: ctype.h:76
#define _UPPER
Definition: ctype.h:65
#define _DIGIT
Definition: ctype.h:67
#define ULONG_MAX
Definition: limits.h:44
#define c
Definition: ke_i.h:80
#define L(x)
Definition: ntvdm.h:50
#define long
Definition: qsort.c:33
unsigned long CDECL wcstoul(const wchar_t *nptr, wchar_t **endptr, int base)
Definition: wcstoul.c:14