1 /* 2 * Copyright (c) 1990, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Copyright (c) 2011 The FreeBSD Foundation 6 * All rights reserved. 7 * Portions of this software were developed by David Chisnall 8 * under sponsorship from the FreeBSD Foundation. 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 * 4. 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 35 #if defined(LIBC_SCCS) && !defined(lint) 36 static char sccsid[] = "@(#)strtoul.c 8.1 (Berkeley) 6/4/93"; 37 #endif /* LIBC_SCCS and not lint */ 38 #include <sys/cdefs.h> 39 __FBSDID("$FreeBSD$"); 40 41 #include "stand.h" 42 #include <limits.h> 43 44 /* 45 * Convert a string to an unsigned long integer. 46 * 47 * Assumes that the upper and lower case 48 * alphabets and digits are each contiguous. 49 */ 50 unsigned long 51 strtoul(const char * __restrict nptr, char ** __restrict endptr, int base) 52 { 53 const char *s; 54 unsigned long acc; 55 char c; 56 unsigned long cutoff; 57 int neg, any, cutlim; 58 59 /* 60 * See strtol for comments as to the logic used. 61 */ 62 s = nptr; 63 do { 64 c = *s++; 65 } while (isspace((unsigned char)c)); 66 if (c == '-') { 67 neg = 1; 68 c = *s++; 69 } else { 70 neg = 0; 71 if (c == '+') 72 c = *s++; 73 } 74 if ((base == 0 || base == 16) && 75 c == '0' && (*s == 'x' || *s == 'X') && 76 ((s[1] >= '0' && s[1] <= '9') || 77 (s[1] >= 'A' && s[1] <= 'F') || 78 (s[1] >= 'a' && s[1] <= 'f'))) { 79 c = s[1]; 80 s += 2; 81 base = 16; 82 } 83 if (base == 0) 84 base = c == '0' ? 8 : 10; 85 acc = any = 0; 86 if (base < 2 || base > 36) 87 goto noconv; 88 89 cutoff = ULONG_MAX / base; 90 cutlim = ULONG_MAX % base; 91 for ( ; ; c = *s++) { 92 if (c >= '0' && c <= '9') 93 c -= '0'; 94 else if (c >= 'A' && c <= 'Z') 95 c -= 'A' - 10; 96 else if (c >= 'a' && c <= 'z') 97 c -= 'a' - 10; 98 else 99 break; 100 if (c >= base) 101 break; 102 if (any < 0 || acc > cutoff || (acc == cutoff && c > cutlim)) 103 any = -1; 104 else { 105 any = 1; 106 acc *= base; 107 acc += c; 108 } 109 } 110 if (any < 0) { 111 acc = ULONG_MAX; 112 errno = ERANGE; 113 } else if (!any) { 114 noconv: 115 errno = EINVAL; 116 } else if (neg) 117 acc = -acc; 118 if (endptr != NULL) 119 *endptr = (char *)(any ? s - 1 : nptr); 120 return (acc); 121 } 122