152845Sphk/*- 252845Sphk * Copyright (c) 1990, 1993 352845Sphk * The Regents of the University of California. All rights reserved. 452845Sphk * 552845Sphk * This code is derived from software contributed to Berkeley by 652845Sphk * Chris Torek. 752845Sphk * 852845Sphk * Redistribution and use in source and binary forms, with or without 952845Sphk * modification, are permitted provided that the following conditions 1052845Sphk * are met: 1152845Sphk * 1. Redistributions of source code must retain the above copyright 1252845Sphk * notice, this list of conditions and the following disclaimer. 1352845Sphk * 2. Redistributions in binary form must reproduce the above copyright 1452845Sphk * notice, this list of conditions and the following disclaimer in the 1552845Sphk * documentation and/or other materials provided with the distribution. 1652845Sphk * 4. Neither the name of the University nor the names of its contributors 1752845Sphk * may be used to endorse or promote products derived from this software 1852845Sphk * without specific prior written permission. 1952845Sphk * 2052845Sphk * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 2152845Sphk * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 2252845Sphk * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 2352845Sphk * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 2452845Sphk * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 2552845Sphk * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 2652845Sphk * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 2752845Sphk * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 2852845Sphk * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 2952845Sphk * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 3052845Sphk * SUCH DAMAGE. 3152845Sphk * 32116189Sobrien * From: @(#)strtol.c 8.1 (Berkeley) 6/4/93 3352845Sphk */ 3452845Sphk 35116189Sobrien#include <sys/cdefs.h> 36116189Sobrien__FBSDID("$FreeBSD$"); 37116189Sobrien 3852845Sphk#include <sys/param.h> 3952845Sphk#include <sys/systm.h> 4052845Sphk#include <sys/ctype.h> 41114216Skan#include <sys/limits.h> 4252845Sphk 4352845Sphk/* 4452845Sphk * Convert a string to a long integer. 4552845Sphk * 4652845Sphk * Ignores `locale' stuff. Assumes that the upper and lower case 4752845Sphk * alphabets and digits are each contiguous. 4852845Sphk */ 4952845Sphklong 5052845Sphkstrtol(nptr, endptr, base) 5152845Sphk const char *nptr; 5253648Sarchie char **endptr; 5352845Sphk int base; 5452845Sphk{ 5552845Sphk const char *s = nptr; 5652845Sphk unsigned long acc; 5752845Sphk unsigned char c; 5852845Sphk unsigned long cutoff; 5952845Sphk int neg = 0, any, cutlim; 6052845Sphk 6152845Sphk /* 6252845Sphk * Skip white space and pick up leading +/- sign if any. 6352845Sphk * If base is 0, allow 0x for hex and 0 for octal, else 6452845Sphk * assume decimal; if base is already 16, allow 0x. 6552845Sphk */ 6652845Sphk do { 6752845Sphk c = *s++; 6852845Sphk } while (isspace(c)); 6952845Sphk if (c == '-') { 7052845Sphk neg = 1; 7152845Sphk c = *s++; 7252845Sphk } else if (c == '+') 7352845Sphk c = *s++; 7452845Sphk if ((base == 0 || base == 16) && 7552845Sphk c == '0' && (*s == 'x' || *s == 'X')) { 7652845Sphk c = s[1]; 7752845Sphk s += 2; 7852845Sphk base = 16; 7952845Sphk } 8052845Sphk if (base == 0) 8152845Sphk base = c == '0' ? 8 : 10; 8252845Sphk 8352845Sphk /* 8452845Sphk * Compute the cutoff value between legal numbers and illegal 8552845Sphk * numbers. That is the largest legal value, divided by the 8652845Sphk * base. An input number that is greater than this value, if 8752845Sphk * followed by a legal input character, is too big. One that 8852845Sphk * is equal to this value may be valid or not; the limit 8952845Sphk * between valid and invalid numbers is then based on the last 9052845Sphk * digit. For instance, if the range for longs is 9152845Sphk * [-2147483648..2147483647] and the input base is 10, 9252845Sphk * cutoff will be set to 214748364 and cutlim to either 9352845Sphk * 7 (neg==0) or 8 (neg==1), meaning that if we have accumulated 9452845Sphk * a value > 214748364, or equal but the next digit is > 7 (or 8), 9552845Sphk * the number is too big, and we will return a range error. 9652845Sphk * 9752845Sphk * Set any if any `digits' consumed; make it negative to indicate 9852845Sphk * overflow. 9952845Sphk */ 10052845Sphk cutoff = neg ? -(unsigned long)LONG_MIN : LONG_MAX; 10152845Sphk cutlim = cutoff % (unsigned long)base; 10252845Sphk cutoff /= (unsigned long)base; 10352845Sphk for (acc = 0, any = 0;; c = *s++) { 10452845Sphk if (!isascii(c)) 10552845Sphk break; 10652845Sphk if (isdigit(c)) 10752845Sphk c -= '0'; 10852845Sphk else if (isalpha(c)) 10952845Sphk c -= isupper(c) ? 'A' - 10 : 'a' - 10; 11052845Sphk else 11152845Sphk break; 11252845Sphk if (c >= base) 11352845Sphk break; 11452845Sphk if (any < 0 || acc > cutoff || (acc == cutoff && c > cutlim)) 11552845Sphk any = -1; 11652845Sphk else { 11752845Sphk any = 1; 11852845Sphk acc *= base; 11952845Sphk acc += c; 12052845Sphk } 12152845Sphk } 12252845Sphk if (any < 0) { 12352845Sphk acc = neg ? LONG_MIN : LONG_MAX; 12452845Sphk } else if (neg) 12552845Sphk acc = -acc; 12652845Sphk if (endptr != 0) 12754006Sarchie *((const char **)endptr) = any ? s - 1 : nptr; 12852845Sphk return (acc); 12952845Sphk} 130