1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1992, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Copyright (c) 2011 The FreeBSD Foundation 8 * All rights reserved. 9 * Portions of this software were developed by David Chisnall 10 * under sponsorship from the FreeBSD Foundation. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 */ 36 37 #include <errno.h> 38 #include <limits.h> 39 #include <stddef.h> 40 #include <stdlib.h> 41 42 /* 43 * Convert a string to an unsigned long long integer. 44 * 45 * Assumes that the upper and lower case 46 * alphabets and digits are each contiguous. 47 */ 48 unsigned long long strtoull(const char *nptr, char **endptr, int base) 49 { 50 const char *s; 51 unsigned long long acc; 52 char c; 53 unsigned long long cutoff; 54 int neg, any, cutlim; 55 56 /* 57 * See strtoq for comments as to the logic used. 58 */ 59 s = nptr; 60 do { 61 c = *s++; 62 } while (isspace((unsigned char)c)); 63 if (c == '-') { 64 neg = 1; 65 c = *s++; 66 } else { 67 neg = 0; 68 if (c == '+') 69 c = *s++; 70 } 71 if ((base == 0 || base == 16) && 72 c == '0' && (*s == 'x' || *s == 'X') && 73 ((s[1] >= '0' && s[1] <= '9') || 74 (s[1] >= 'A' && s[1] <= 'F') || 75 (s[1] >= 'a' && s[1] <= 'f'))) { 76 c = s[1]; 77 s += 2; 78 base = 16; 79 } 80 if (base == 0) 81 base = c == '0' ? 8 : 10; 82 acc = any = 0; 83 84 cutoff = ULLONG_MAX / base; 85 cutlim = ULLONG_MAX % base; 86 for ( ; ; c = *s++) { 87 if (c >= '0' && c <= '9') 88 c -= '0'; 89 else if (c >= 'A' && c <= 'Z') 90 c -= 'A' - 10; 91 else if (c >= 'a' && c <= 'z') 92 c -= '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 = ULLONG_MAX; 107 } else if (neg) 108 acc = -acc; 109 if (endptr != NULL) 110 *endptr = (char *)(any ? s - 1 : nptr); 111 return (acc); 112 } 113