1 /* $FreeBSD$ */ 2 /* $NetBSD: _strtoul.h,v 1.1 2008/08/20 12:42:26 joerg Exp $ */ 3 4 /*- 5 * SPDX-License-Identifier: BSD-3-Clause 6 * 7 * Copyright (c) 1990, 1993 8 * The Regents of the University of California. All rights reserved. 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 * Original version ID: 35 * NetBSD: src/lib/libc/locale/_wcstoul.h,v 1.2 2003/08/07 16:43:03 agc Exp 36 */ 37 38 /* 39 * function template for strtoul, strtoull and strtoumax. 40 * 41 * parameters: 42 * _FUNCNAME : function name 43 * __UINT : return type 44 * __UINT_MAX : upper limit of the return type 45 */ 46 47 __UINT 48 _FUNCNAME(const char *nptr, char **endptr, int base) 49 { 50 const char *s; 51 __UINT acc, cutoff; 52 unsigned char c; 53 int any, cutlim, i, neg; 54 55 /* check base value */ 56 if (base && (base < 2 || base > 36)) { 57 #if !defined(_KERNEL) && !defined(_STANDALONE) 58 errno = EINVAL; 59 return (0); 60 #else 61 panic("%s: invalid base %d", __func__, base); 62 #endif 63 } 64 65 /* 66 * Skip white space and pick up leading +/- sign if any. 67 * If base is 0, allow 0x for hex and 0 for octal, else 68 * assume decimal; if base is already 16, allow 0x. 69 */ 70 s = nptr; 71 do { 72 c = *s++; 73 } while (isspace(c)); 74 if (c == '-') { 75 neg = 1; 76 c = *s++; 77 } else { 78 neg = 0; 79 if (c == '+') 80 c = *s++; 81 } 82 if ((base == 0 || base == 16) && 83 c == '0' && (*s == 'x' || *s == 'X')) { 84 c = s[1]; 85 s += 2; 86 base = 16; 87 } 88 if (base == 0) 89 base = (c == '0' ? 8 : 10); 90 91 /* 92 * See strtol for comments as to the logic used. 93 */ 94 cutoff = __UINT_MAX / (__UINT)base; 95 cutlim = (int)(__UINT_MAX % (__UINT)base); 96 for (acc = 0, any = 0;; c = *s++) { 97 if (isdigit(c)) 98 i = c - '0'; 99 else if (isalpha(c)) 100 i = c - (isupper(c) ? 'A' - 10 : 'a' - 10); 101 else 102 break; 103 if (i >= base) 104 break; 105 if (any < 0) 106 continue; 107 if (acc > cutoff || (acc == cutoff && i > cutlim)) { 108 acc = __UINT_MAX; 109 #if !defined(_KERNEL) && !defined(_STANDALONE) 110 any = -1; 111 errno = ERANGE; 112 #else 113 any = 0; 114 break; 115 #endif 116 } else { 117 any = 1; 118 acc *= (__UINT)base; 119 acc += i; 120 } 121 } 122 if (neg && any > 0) 123 acc = -acc; 124 if (endptr != NULL) 125 /* LINTED interface specification */ 126 *endptr = __DECONST(void *, any ? s - 1 : nptr); 127 return (acc); 128 } 129