GCC Code Coverage Report
Directory: ./ Exec Total Coverage
File: lib/libc/stdlib/strtol.c Lines: 0 48 0.0 %
Date: 2017-11-13 Branches: 0 48 0.0 %

Line Branch Exec Source
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/*	$OpenBSD: strtol.c,v 1.12 2017/07/06 16:23:11 millert Exp $ */
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/*
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 * Copyright (c) 1990 The Regents of the University of California.
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 * All rights reserved.
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 *
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 * Redistribution and use in source and binary forms, with or without
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 * modification, are permitted provided that the following conditions
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 * are met:
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 * 1. Redistributions of source code must retain the above copyright
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 *    notice, this list of conditions and the following disclaimer.
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 * 2. Redistributions in binary form must reproduce the above copyright
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 *    notice, this list of conditions and the following disclaimer in the
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 *    documentation and/or other materials provided with the distribution.
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 * 3. Neither the name of the University nor the names of its contributors
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 *    may be used to endorse or promote products derived from this software
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 *    without specific prior written permission.
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 *
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 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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 * SUCH DAMAGE.
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 */
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#include <ctype.h>
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#include <errno.h>
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#include <limits.h>
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#include <stdlib.h>
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/*
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 * Convert a string to a long integer.
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 *
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 * Ignores `locale' stuff.  Assumes that the upper and lower case
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 * alphabets and digits are each contiguous.
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 */
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long
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strtol(const char *nptr, char **endptr, int base)
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{
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	const char *s;
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	long acc, cutoff;
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	int c;
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	int neg, any, cutlim;
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	/*
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	 * Ensure that base is between 2 and 36 inclusive, or the special
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	 * value of 0.
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	 */
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	if (base < 0 || base == 1 || base > 36) {
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		if (endptr != 0)
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			*endptr = (char *)nptr;
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		errno = EINVAL;
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		return 0;
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	}
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	/*
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	 * Skip white space and pick up leading +/- sign if any.
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	 * If base is 0, allow 0x for hex and 0 for octal, else
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	 * assume decimal; if base is already 16, allow 0x.
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	 */
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	s = nptr;
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	do {
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		c = (unsigned char) *s++;
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	} while (isspace(c));
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	if (c == '-') {
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		neg = 1;
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		c = *s++;
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	} else {
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		neg = 0;
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		if (c == '+')
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			c = *s++;
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	}
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	if ((base == 0 || base == 16) && c == '0' &&
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	    (*s == 'x' || *s == 'X') && isxdigit((unsigned char)s[1])) {
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		c = s[1];
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		s += 2;
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		base = 16;
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	}
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	if (base == 0)
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		base = c == '0' ? 8 : 10;
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	/*
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	 * Compute the cutoff value between legal numbers and illegal
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	 * numbers.  That is the largest legal value, divided by the
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	 * base.  An input number that is greater than this value, if
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	 * followed by a legal input character, is too big.  One that
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	 * is equal to this value may be valid or not; the limit
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	 * between valid and invalid numbers is then based on the last
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	 * digit.  For instance, if the range for longs is
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	 * [-2147483648..2147483647] and the input base is 10,
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	 * cutoff will be set to 214748364 and cutlim to either
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	 * 7 (neg==0) or 8 (neg==1), meaning that if we have accumulated
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	 * a value > 214748364, or equal but the next digit is > 7 (or 8),
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	 * the number is too big, and we will return a range error.
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	 *
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	 * Set any if any `digits' consumed; make it negative to indicate
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	 * overflow.
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	 */
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	cutoff = neg ? LONG_MIN : LONG_MAX;
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	cutlim = cutoff % base;
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	cutoff /= base;
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	if (neg) {
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		if (cutlim > 0) {
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			cutlim -= base;
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			cutoff += 1;
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		}
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		cutlim = -cutlim;
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	}
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	for (acc = 0, any = 0;; c = (unsigned char) *s++) {
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		if (isdigit(c))
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			c -= '0';
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		else if (isalpha(c))
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			c -= isupper(c) ? 'A' - 10 : 'a' - 10;
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		else
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			break;
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		if (c >= base)
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			break;
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		if (any < 0)
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			continue;
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		if (neg) {
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			if (acc < cutoff || (acc == cutoff && c > cutlim)) {
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				any = -1;
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				acc = LONG_MIN;
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				errno = ERANGE;
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			} else {
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				any = 1;
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				acc *= base;
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				acc -= c;
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			}
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		} else {
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			if (acc > cutoff || (acc == cutoff && c > cutlim)) {
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				any = -1;
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				acc = LONG_MAX;
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				errno = ERANGE;
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			} else {
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				any = 1;
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				acc *= base;
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				acc += c;
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			}
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		}
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	}
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	if (endptr != 0)
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		*endptr = (char *) (any ? s - 1 : nptr);
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	return (acc);
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}
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DEF_STRONG(strtol);