text: /* $NetBSD: _wcstoul.h,v 1.2 2003/08/07 16:43:03 agc Exp $ */
  
  /*
   * Copyright (c) 1990, 1993
   *	The Regents of the University of California.  All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   * 3. Neither the name of the University nor the names of its contributors
   *    may be used to endorse or promote products derived from this software
   *    without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
   * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
   * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   * SUCH DAMAGE.
   *
   * Original version ID:
   * @(#)strtoul.c	8.1 (Berkeley) 6/4/93
   * Citrus: xpg4dl/FreeBSD/lib/libc/locale/wcstoul.c,v 1.2 2001/09/21 16:11:41 yamt Exp
   * NetBSD: wcstoul.c,v 1.1 2001/09/27 16:30:37 yamt Exp
   */
  
  /*
   * function template for wcstoul, wcstoull and wcstoumax.
   *
   * parameters:
   *	_FUNCNAME  : function name
   *      __UINT     : return type
   *      __UINT_MAX : upper limit of the return type
   */
  
  __UINT
  _FUNCNAME(nptr, endptr, base)
  	const wchar_t *nptr;
  	wchar_t **endptr;
  	int base;
  {
  	const wchar_t *s;
  	__UINT acc, cutoff;
  	wint_t wc;
  	int i;
  	int neg, any, cutlim;
  
  	_DIAGASSERT(nptr != NULL);
  	/* endptr may be NULL */
  
  	if (base && (base < 2 || base > 36)) {
  		errno = EINVAL;
  		return 0;
  	}
  
  	/*
  	 * 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.
  	 */
  	s = nptr;
  	do {
  		wc = (wchar_t) *s++;
  	} while (iswspace(wc));
  	if (wc == L'-') {
  		neg = 1;
  		wc = *s++;
  	} else {
  		neg = 0;
  		if (wc == L'+')
  			wc = *s++;
  	}
  	if ((base == 0 || base == 16) &&
  	    wc == L'0' && (*s == L'x' || *s == L'X')) {
  		wc = s[1];
  		s += 2;
  		base = 16;
  	}
  	if (base == 0)
  		base = wc == L'0' ? 8 : 10;
  
  	/*
  	 * See strtoul for comments as to the logic used.
  	 */
  	cutoff = __UINT_MAX / (__UINT)base;
  	cutlim = (int)(__UINT_MAX % (__UINT)base);
  	for (acc = 0, any = 0;; wc = (wchar_t) *s++) {
  		i = __wctoint(wc);
  		if (i == (wint_t)-1)
  			break;
  		if (i >= base)
  			break;
  		if (any < 0)
  			continue;
  		if (acc > cutoff || (acc == cutoff && i > cutlim)) {
  			any = -1;
  			acc = __UINT_MAX;
  			errno = ERANGE;
  		} else {
  			any = 1;
  			acc *= (__UINT)base;
  			acc += i;
  		}
  	}
  	if (neg && any > 0)
  		acc = -acc;
  	if (endptr != 0)
  		/* LINTED interface specification */
  		*endptr = (wchar_t *)(any ? s - 1 : nptr);
  	return (acc);
  }
  