1 /*- 2 * Copyright (c) 1990, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Copyright (c) 2011 The FreeBSD Foundation 6 * All rights reserved. 7 * Portions of this software were developed by David Chisnall 8 * under sponsorship from the FreeBSD Foundation. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * @(#)strtol.c 8.1 (Berkeley) 6/4/93 35 * $FreeBSD: head/lib/libc/stdlib/strtol.c 251672 2013-06-13 00:19:30Z emaste $ 36 */ 37 38 39 #include <limits.h> 40 #include <ctype.h> 41 #include <errno.h> 42 #include <stdlib.h> 43 #include "xlocale_private.h" 44 45 46 /* 47 * Convert a string to a long integer. 48 * 49 * Assumes that the upper and lower case 50 * alphabets and digits are each contiguous. 51 */ 52 long 53 strtol_l(const char * __restrict nptr, char ** __restrict endptr, int base, 54 locale_t locale) 55 { 56 const char *s; 57 unsigned long acc; 58 char c; 59 unsigned long cutoff; 60 int neg, any, cutlim; 61 FIX_LOCALE(locale); 62 63 /* 64 * Skip white space and pick up leading +/- sign if any. 65 * If base is 0, allow 0x for hex and 0 for octal, else 66 * assume decimal; if base is already 16, allow 0x. 67 */ 68 s = nptr; 69 do { 70 c = *s++; 71 } while (isspace_l((unsigned char)c, locale)); 72 if (c == '-') { 73 neg = 1; 74 c = *s++; 75 } else { 76 neg = 0; 77 if (c == '+') 78 c = *s++; 79 } 80 if ((base == 0 || base == 16) && 81 c == '0' && (*s == 'x' || *s == 'X') && 82 ((s[1] >= '0' && s[1] <= '9') || 83 (s[1] >= 'A' && s[1] <= 'F') || 84 (s[1] >= 'a' && s[1] <= 'f'))) { 85 c = s[1]; 86 s += 2; 87 base = 16; 88 } 89 if (base == 0) 90 base = c == '0' ? 8 : 10; 91 acc = any = 0; 92 if (base < 2 || base > 36) 93 goto noconv; 94 95 /* 96 * Compute the cutoff value between legal numbers and illegal 97 * numbers. That is the largest legal value, divided by the 98 * base. An input number that is greater than this value, if 99 * followed by a legal input character, is too big. One that 100 * is equal to this value may be valid or not; the limit 101 * between valid and invalid numbers is then based on the last 102 * digit. For instance, if the range for longs is 103 * [-2147483648..2147483647] and the input base is 10, 104 * cutoff will be set to 214748364 and cutlim to either 105 * 7 (neg==0) or 8 (neg==1), meaning that if we have accumulated 106 * a value > 214748364, or equal but the next digit is > 7 (or 8), 107 * the number is too big, and we will return a range error. 108 * 109 * Set 'any' if any `digits' consumed; make it negative to indicate 110 * overflow. 111 */ 112 cutoff = neg ? (unsigned long)-(LONG_MIN + LONG_MAX) + LONG_MAX 113 : LONG_MAX; 114 cutlim = cutoff % base; 115 cutoff /= base; 116 for ( ; ; c = *s++) { 117 if (c >= '0' && c <= '9') 118 c -= '0'; 119 else if (c >= 'A' && c <= 'Z') 120 c -= 'A' - 10; 121 else if (c >= 'a' && c <= 'z') 122 c -= 'a' - 10; 123 else 124 break; 125 if (c >= base) 126 break; 127 if (any < 0 || acc > cutoff || (acc == cutoff && c > cutlim)) 128 any = -1; 129 else { 130 any = 1; 131 acc *= base; 132 acc += c; 133 } 134 } 135 if (any < 0) { 136 acc = neg ? LONG_MIN : LONG_MAX; 137 errno = ERANGE; 138 } else if (!any) { 139 noconv: 140 errno = EINVAL; 141 } else if (neg) 142 acc = -acc; 143 if (endptr != NULL) 144 *endptr = (char *)(any ? s - 1 : nptr); 145 return (acc); 146 } 147 long 148 strtol(const char * __restrict nptr, char ** __restrict endptr, int base) 149 { 150 return strtol_l(nptr, endptr, base, __get_locale()); 151 } 152 long double 153 strtold(const char * __restrict nptr, char ** __restrict endptr) 154 { 155 return strtold_l(nptr, endptr, __get_locale()); 156 } 157