strtoul.c revision 82995
11573Srgrimes/* 21573Srgrimes * Copyright (c) 1990, 1993 31573Srgrimes * The Regents of the University of California. All rights reserved. 41573Srgrimes * 51573Srgrimes * Redistribution and use in source and binary forms, with or without 61573Srgrimes * modification, are permitted provided that the following conditions 71573Srgrimes * are met: 81573Srgrimes * 1. Redistributions of source code must retain the above copyright 91573Srgrimes * notice, this list of conditions and the following disclaimer. 101573Srgrimes * 2. Redistributions in binary form must reproduce the above copyright 111573Srgrimes * notice, this list of conditions and the following disclaimer in the 121573Srgrimes * documentation and/or other materials provided with the distribution. 131573Srgrimes * 3. All advertising materials mentioning features or use of this software 141573Srgrimes * must display the following acknowledgement: 151573Srgrimes * This product includes software developed by the University of 161573Srgrimes * California, Berkeley and its contributors. 171573Srgrimes * 4. Neither the name of the University nor the names of its contributors 181573Srgrimes * may be used to endorse or promote products derived from this software 191573Srgrimes * without specific prior written permission. 201573Srgrimes * 211573Srgrimes * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 221573Srgrimes * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 231573Srgrimes * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 241573Srgrimes * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 251573Srgrimes * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 261573Srgrimes * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 271573Srgrimes * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 281573Srgrimes * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 291573Srgrimes * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 301573Srgrimes * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 311573Srgrimes * SUCH DAMAGE. 3282995Sache * 3382995Sache * $FreeBSD: head/lib/libc/stdlib/strtoul.c 82995 2001-09-04 17:41:20Z ache $ 341573Srgrimes */ 351573Srgrimes 361573Srgrimes#if defined(LIBC_SCCS) && !defined(lint) 371573Srgrimesstatic char sccsid[] = "@(#)strtoul.c 8.1 (Berkeley) 6/4/93"; 381573Srgrimes#endif /* LIBC_SCCS and not lint */ 391573Srgrimes 401573Srgrimes#include <limits.h> 411573Srgrimes#include <ctype.h> 421573Srgrimes#include <errno.h> 431573Srgrimes#include <stdlib.h> 441573Srgrimes 451573Srgrimes/* 461573Srgrimes * Convert a string to an unsigned long integer. 471573Srgrimes * 4882975Sache * Assumes that the upper and lower case 491573Srgrimes * alphabets and digits are each contiguous. 501573Srgrimes */ 511573Srgrimesunsigned long 521573Srgrimesstrtoul(nptr, endptr, base) 531573Srgrimes const char *nptr; 541573Srgrimes char **endptr; 551573Srgrimes register int base; 561573Srgrimes{ 5782975Sache register const char *s; 581573Srgrimes register unsigned long acc; 599845Sache register unsigned char c; 601573Srgrimes register unsigned long cutoff; 6182975Sache register int neg, any, cutlim; 621573Srgrimes 631573Srgrimes /* 641573Srgrimes * See strtol for comments as to the logic used. 651573Srgrimes */ 6682975Sache s = nptr; 671573Srgrimes do { 681573Srgrimes c = *s++; 691573Srgrimes } while (isspace(c)); 701573Srgrimes if (c == '-') { 711573Srgrimes neg = 1; 721573Srgrimes c = *s++; 7382975Sache } else { 7482975Sache neg = 0; 7582975Sache if (c == '+') 7682975Sache c = *s++; 7782975Sache } 781573Srgrimes if ((base == 0 || base == 16) && 791573Srgrimes c == '0' && (*s == 'x' || *s == 'X')) { 801573Srgrimes c = s[1]; 811573Srgrimes s += 2; 821573Srgrimes base = 16; 831573Srgrimes } 841573Srgrimes if (base == 0) 851573Srgrimes base = c == '0' ? 8 : 10; 8682982Sache acc = any = 0; 8782975Sache if (base < 2 || base > 36) 8882975Sache goto noconv; 8982975Sache 9082975Sache cutoff = ULONG_MAX / base; 9182975Sache cutlim = ULONG_MAX % base; 9282982Sache for ( ; ; c = *s++) { 939845Sache if (!isascii(c)) 949845Sache break; 951573Srgrimes if (isdigit(c)) 961573Srgrimes c -= '0'; 971573Srgrimes else if (isalpha(c)) 981573Srgrimes c -= isupper(c) ? 'A' - 10 : 'a' - 10; 991573Srgrimes else 1001573Srgrimes break; 1011573Srgrimes if (c >= base) 1021573Srgrimes break; 10317141Sjkh if (any < 0 || acc > cutoff || (acc == cutoff && c > cutlim)) 1041573Srgrimes any = -1; 1051573Srgrimes else { 1061573Srgrimes any = 1; 1071573Srgrimes acc *= base; 1081573Srgrimes acc += c; 1091573Srgrimes } 1101573Srgrimes } 1111573Srgrimes if (any < 0) { 1121573Srgrimes acc = ULONG_MAX; 1131573Srgrimes errno = ERANGE; 11482975Sache } else if (!any) { 11582975Sachenoconv: 11682975Sache errno = EINVAL; 1171573Srgrimes } else if (neg) 1181573Srgrimes acc = -acc; 11982975Sache if (endptr != NULL) 1201573Srgrimes *endptr = (char *)(any ? s - 1 : nptr); 1211573Srgrimes return (acc); 1221573Srgrimes} 123