1 /* $DragonFly: src/lib/libc/stdlib/_strtoul.h,v 1.1 2005/03/17 15:09:01 joerg Exp $ */ 2 3 /*- 4 * Copyright (c) 1990, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * Original version ID: 32 * $NetBSD: src/lib/libc/locale/_wcstoul.h,v 1.2 2003/08/07 16:43:03 agc Exp $ 33 */ 34 35 /* 36 * function template for strtoul, strtoull and strtoumax. 37 * 38 * parameters: 39 * _FUNCNAME : function name 40 * __UINT : return type 41 * __UINT_MAX : upper limit of the return type 42 */ 43 44 __UINT 45 _FUNCNAME(const char *nptr, char **endptr, int base) 46 { 47 const char *s; 48 __UINT acc, cutoff; 49 char c; 50 int i, neg, any, cutlim; 51 52 _DIAGASSERT(nptr != NULL); 53 /* endptr may be NULL */ 54 55 /* check base value */ 56 if (base && (base < 2 || base > 36)) { 57 errno = EINVAL; 58 return(0); 59 } 60 61 /* 62 * Skip white space and pick up leading +/- sign if any. 63 * If base is 0, allow 0x for hex and 0 for octal, else 64 * assume decimal; if base is already 16, allow 0x. 65 */ 66 s = nptr; 67 do { 68 c = *s++; 69 } while (isspace(c)); 70 if (c == '-') { 71 neg = 1; 72 c = *s++; 73 } else { 74 neg = 0; 75 if (c == '+') 76 c = *s++; 77 } 78 if ((base == 0 || base == 16) && 79 c == '0' && (*s == 'x' || *s == 'X')) { 80 c = s[1]; 81 s += 2; 82 base = 16; 83 } 84 if (base == 0) 85 base = c == '0' ? 8 : 10; 86 87 /* 88 * See strtol for comments as to the logic used. 89 */ 90 cutoff = __UINT_MAX / (__UINT)base; 91 cutlim = (int)(__UINT_MAX % (__UINT)base); 92 for (acc = 0, any = 0;; c = *s++) { 93 if (!isascii(c)) 94 break; 95 if (isdigit(c)) 96 i = c - '0'; 97 else if (isalpha(c)) 98 i = c - (isupper(c) ? 'A' - 10 : 'a' - 10); 99 else 100 break; 101 if (i >= base) 102 break; 103 if (any < 0) 104 continue; 105 if (acc > cutoff || (acc == cutoff && i > cutlim)) { 106 any = -1; 107 acc = __UINT_MAX; 108 errno = ERANGE; 109 } else { 110 any = 1; 111 acc *= (__UINT)base; 112 acc += i; 113 } 114 } 115 if (neg && any > 0) 116 acc = -acc; 117 if (endptr != 0) 118 /* LINTED interface specification */ 119 *endptr = __DECONST(char *, (any ? s - 1 : nptr)); 120 return(acc); 121 } 122