wcstol

long wcstol ( const wchar_t *  nptr, wchar_t **  endptr, int  base  ) Definition at line 16 of file wcstol.c. Referenced by CheckUnattendedSetup(), ATL::CRegObject::do_process_key(), GetIntField(), LanguagePage(), LoadKeyboardLayoutW(), and WSAStringToAddressW(). { const wchar_t *s = nptr; long acc; int c; unsigned long cutoff; int neg = 0, any, cutlim; /* * Skip white space and pick up leading +/- sign if any. * If base is 0, allow 0x for hex and 0 for octal, else * assume decimal; if base is already 16, allow 0x. */ do { c = *s++; } while (iswctype(c, _SPACE)); if (c == '-') { 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; /* * Compute the cutoff value between legal numbers and illegal * numbers. That is the largest legal value, divided by the * base. An input number that is greater than this value, if * followed by a legal input character, is too big. One that * is equal to this value may be valid or not; the limit * between valid and invalid numbers is then based on the last * digit. For instance, if the range for longs is * [-2147483648..2147483647] and the input base is 10, * cutoff will be set to 214748364 and cutlim to either * 7 (neg==0) or 8 (neg==1), meaning that if we have accumulated * a value > 214748364, or equal but the next digit is > 7 (or 8), * the number is too big, and we will return a range error. * * Set any if any `digits' consumed; make it negative to indicate * overflow. */ cutoff = neg ? ((unsigned long)LONG_MAX+1) : LONG_MAX; cutlim = cutoff % (unsigned long)base; cutoff /= (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 || (unsigned long)acc > cutoff || (acc == cutoff && c > cutlim)) any = -1; else { any = 1; acc *= base; acc += c; } } if (any < 0) { acc = neg ? LONG_MIN : LONG_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; }