1 /* $NetBSD: _strtoul.h,v 1.1 2008/08/20 12:42:26 joerg Exp $ */ 2 3 /*- 4 * SPDX-License-Identifier: BSD-3-Clause 5 * 6 * Copyright (c) 1990, 1993 7 * The Regents of the University of California. All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * Original version ID: 34 * NetBSD: src/lib/libc/locale/_wcstoul.h,v 1.2 2003/08/07 16:43:03 agc Exp 35 */ 36 37 /* 38 * function template for strtoul, strtoull and strtoumax. 39 * 40 * parameters: 41 * _FUNCNAME : function name 42 * __UINT : return type 43 * __UINT_MAX : upper limit of the return type 44 */ 45 46 __UINT 47 _FUNCNAME(const char *nptr, char **endptr, int base) 48 { 49 const char *s; 50 __UINT acc, cutoff; 51 unsigned char c; 52 int any, cutlim, i, neg; 53 54 /* check base value */ 55 if (base && (base < 2 || base > 36)) { 56 #if !defined(_KERNEL) && !defined(_STANDALONE) 57 errno = EINVAL; 58 return (0); 59 #else 60 panic("%s: invalid base %d", __func__, base); 61 #endif 62 } 63 64 /* 65 * Skip white space and pick up leading +/- sign if any. 66 * If base is 0, allow 0x for hex and 0 for octal, else 67 * assume decimal; if base is already 16, allow 0x. 68 */ 69 s = nptr; 70 do { 71 c = *s++; 72 } while (isspace(c)); 73 if (c == '-') { 74 neg = 1; 75 c = *s++; 76 } else { 77 neg = 0; 78 if (c == '+') 79 c = *s++; 80 } 81 if ((base == 0 || base == 16) && 82 c == '0' && (*s == 'x' || *s == 'X')) { 83 c = s[1]; 84 s += 2; 85 base = 16; 86 } 87 if (base == 0) 88 base = (c == '0' ? 8 : 10); 89 90 /* 91 * See strtol for comments as to the logic used. 92 */ 93 cutoff = __UINT_MAX / (__UINT)base; 94 cutlim = (int)(__UINT_MAX % (__UINT)base); 95 for (acc = 0, any = 0;; c = *s++) { 96 if (isdigit(c)) 97 i = c - '0'; 98 else if (isalpha(c)) 99 i = c - (isupper(c) ? 'A' - 10 : 'a' - 10); 100 else 101 break; 102 if (i >= base) 103 break; 104 if (any < 0) 105 continue; 106 if (acc > cutoff || (acc == cutoff && i > cutlim)) { 107 acc = __UINT_MAX; 108 #if !defined(_KERNEL) && !defined(_STANDALONE) 109 any = -1; 110 errno = ERANGE; 111 #else 112 any = 0; 113 break; 114 #endif 115 } else { 116 any = 1; 117 acc *= (__UINT)base; 118 acc += i; 119 } 120 } 121 if (neg && any > 0) 122 acc = -acc; 123 if (endptr != NULL) 124 /* LINTED interface specification */ 125 *endptr = __DECONST(void *, any ? s - 1 : nptr); 126 return (acc); 127 } 128