1 /* $OpenBSD: strtoull.c,v 1.9 2017/07/06 16:23:11 millert Exp $ */ 2 /* 3 * Copyright (c) 1992 The Regents of the University of California. 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. Neither the name of the University nor the names of its contributors 15 * may be used to endorse or promote products derived from this software 16 * without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28 * SUCH DAMAGE. 29 */ 30 31 #include <sys/types.h> 32 33 #include <ctype.h> 34 #include <errno.h> 35 #include <limits.h> 36 #include <stdlib.h> 37 38 /* 39 * Convert a string to an unsigned long long. 40 * 41 * Ignores `locale' stuff. Assumes that the upper and lower case 42 * alphabets and digits are each contiguous. 43 */ 44 unsigned long long 45 strtoull(const char *nptr, char **endptr, int base) 46 { 47 const char *s; 48 unsigned long long acc, cutoff; 49 int c; 50 int neg, any, cutlim; 51 52 /* 53 * See strtoll for comments as to the logic used. 54 */ 55 if (base < 0 || base == 1 || base > 36) { 56 if (endptr != 0) 57 *endptr = (char *)nptr; 58 errno = EINVAL; 59 return 0; 60 } 61 62 s = nptr; 63 do { 64 c = (unsigned char) *s++; 65 } while (isspace(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) && c == '0' && 75 (*s == 'x' || *s == 'X') && isxdigit((unsigned char)s[1])) { 76 c = s[1]; 77 s += 2; 78 base = 16; 79 } 80 if (base == 0) 81 base = c == '0' ? 8 : 10; 82 83 cutoff = ULLONG_MAX / (unsigned long long)base; 84 cutlim = ULLONG_MAX % (unsigned long long)base; 85 for (acc = 0, any = 0;; c = (unsigned char) *s++) { 86 if (isdigit(c)) 87 c -= '0'; 88 else if (isalpha(c)) 89 c -= isupper(c) ? 'A' - 10 : 'a' - 10; 90 else 91 break; 92 if (c >= base) 93 break; 94 if (any < 0) 95 continue; 96 if (acc > cutoff || (acc == cutoff && c > cutlim)) { 97 any = -1; 98 acc = ULLONG_MAX; 99 errno = ERANGE; 100 } else { 101 any = 1; 102 acc *= (unsigned long long)base; 103 acc += c; 104 } 105 } 106 if (neg && any > 0) 107 acc = -acc; 108 if (endptr != 0) 109 *endptr = (char *) (any ? s - 1 : nptr); 110 return (acc); 111 } 112 DEF_STRONG(strtoull); 113 114 __weak_alias(strtouq, strtoull); 115