1 /*- 2 * Copyright (c) 1990, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * Original version ID: 30 * $NetBSD: src/lib/libc/locale/_wcstol.h,v 1.2 2003/08/07 16:43:03 agc Exp $ 31 */ 32 33 /* 34 * function template for strtol, strtoll and strtoimax. 35 * 36 * parameters: 37 * _FUNCNAME : function name 38 * __INT : return type 39 * __INT_MIN : lower limit of the return type 40 * __INT_MAX : upper limit of the return type 41 */ 42 43 __INT 44 _FUNCNAME(const char *nptr, char **endptr, int base) 45 { 46 const char *s; 47 __INT acc, cutoff; 48 char c; 49 int i, neg, any, cutlim; 50 51 _DIAGASSERT(nptr != NULL); 52 /* endptr may be NULL */ 53 54 /* check base value */ 55 if (base && (base < 2 || base > 36)) { 56 errno = EINVAL; 57 return(0); 58 } 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(c)); 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 c = s[1]; 80 s += 2; 81 base = 16; 82 } 83 if (base == 0) 84 base = c == '0' ? 8 : 10; 85 86 /* 87 * Compute the cutoff value between legal numbers and illegal 88 * numbers. That is the largest legal value, divided by the 89 * base. An input number that is greater than this value, if 90 * followed by a legal input character, is too big. One that 91 * is equal to this value may be valid or not; the limit 92 * between valid and invalid numbers is then based on the last 93 * digit. For instance, if the range for longs is 94 * [-2147483648..2147483647] and the input base is 10, 95 * cutoff will be set to 214748364 and cutlim to either 96 * 7 (neg==0) or 8 (neg==1), meaning that if we have accumulated 97 * a value > 214748364, or equal but the next digit is > 7 (or 8), 98 * the number is too big, and we will return a range error. 99 * 100 * Set any if any `digits' consumed; make it negative to indicate 101 * overflow. 102 */ 103 cutoff = neg ? __INT_MIN : __INT_MAX; 104 cutlim = (int)(cutoff % base); 105 cutoff /= base; 106 if (neg) { 107 if (cutlim > 0) { 108 cutlim -= base; 109 cutoff += 1; 110 } 111 cutlim = -cutlim; 112 } 113 for (acc = 0, any = 0;; c = *s++) { 114 if (!isascii(c)) 115 break; 116 if (isdigit(c)) 117 i = c - '0'; 118 else if (isalpha(c)) 119 i = c - (isupper(c) ? 'A' - 10 : 'a' - 10); 120 else 121 break; 122 if (i >= base) 123 break; 124 if (any < 0) 125 continue; 126 if (neg) { 127 if (acc < cutoff || (acc == cutoff && i > cutlim)) { 128 any = -1; 129 acc = __INT_MIN; 130 errno = ERANGE; 131 } else { 132 any = 1; 133 acc *= base; 134 acc -= i; 135 } 136 } else { 137 if (acc > cutoff || (acc == cutoff && i > cutlim)) { 138 any = -1; 139 acc = __INT_MAX; 140 errno = ERANGE; 141 } else { 142 any = 1; 143 acc *= base; 144 acc += i; 145 } 146 } 147 } 148 if (endptr != NULL) 149 /* LINTED interface specification */ 150 *endptr = __DECONST(char *, (any ? s - 1 : nptr)); 151 return(acc); 152 } 153