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. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. 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 34#include "config.h" 35 36#if defined(LIBC_SCCS) && !defined(lint) 37static const char sccsid[] = "@(#)strtoul.c 8.1 (Berkeley) 6/4/93"; 38#endif /* LIBC_SCCS and not lint */ 39 40#include <limits.h> 41#include <ctype.h> 42#include <errno.h> 43#include <stdlib.h> 44 45/* 46 * Convert a string to an unsigned long integer. 47 * 48 * Ignores `locale' stuff. Assumes that the upper and lower case 49 * alphabets and digits are each contiguous. 50 * 51 * PUBLIC: #ifndef HAVE_STRTOUL 52 * PUBLIC: unsigned long strtoul __P((const char *, char **, int)); 53 * PUBLIC: #endif 54 */ 55unsigned long 56strtoul(nptr, endptr, base) 57 const char *nptr; 58 char **endptr; 59 register int base; 60{ 61 register const char *s = nptr; 62 register unsigned long acc; 63 register int c; 64 register unsigned long cutoff; 65 register int neg = 0, any, cutlim; 66 67 /* 68 * See strtol for comments as to the logic used. 69 */ 70 do { 71 c = *s++; 72 } while (isspace(c)); 73 if (c == '-') { 74 neg = 1; 75 c = *s++; 76 } else if (c == '+') 77 c = *s++; 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 cutoff = (unsigned long)ULONG_MAX / (unsigned long)base; 87 cutlim = (unsigned long)ULONG_MAX % (unsigned long)base; 88 for (acc = 0, any = 0;; c = *s++) { 89 if (isdigit(c)) 90 c -= '0'; 91 else if (isalpha(c)) 92 c -= isupper(c) ? 'A' - 10 : 'a' - 10; 93 else 94 break; 95 if (c >= base) 96 break; 97 if (any < 0 || acc > cutoff || acc == cutoff && c > cutlim) 98 any = -1; 99 else { 100 any = 1; 101 acc *= base; 102 acc += c; 103 } 104 } 105 if (any < 0) { 106 acc = ULONG_MAX; 107 errno = ERANGE; 108 } else if (neg) 109 acc = -acc; 110 if (endptr != 0) 111 *endptr = (char *)(any ? s - 1 : nptr); 112 return (acc); 113} 114