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