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 <stdint.h> 41 #include <stdlib.h> 42 43 /* 44 * Convert a string to an unsigned long long integer. 45 * 46 * Assumes that the upper and lower case 47 * alphabets and digits are each contiguous. 48 */ 49 unsigned long long strtoull(const char *nptr, char **endptr, int base) 50 { 51 const char *s; 52 unsigned long long acc; 53 char c; 54 unsigned long long cutoff; 55 int neg, any, cutlim; 56 57 /* 58 * See strtoq for comments as to the logic used. 59 */ 60 s = nptr; 61 do { 62 c = *s++; 63 } while (isspace((unsigned char)c)); 64 if (c == '-') { 65 neg = 1; 66 c = *s++; 67 } else { 68 neg = 0; 69 if (c == '+') 70 c = *s++; 71 } 72 if ((base == 0 || base == 16) && 73 c == '0' && (*s == 'x' || *s == 'X') && 74 ((s[1] >= '0' && s[1] <= '9') || 75 (s[1] >= 'A' && s[1] <= 'F') || 76 (s[1] >= 'a' && s[1] <= 'f'))) { 77 c = s[1]; 78 s += 2; 79 base = 16; 80 } 81 if (base == 0) 82 base = c == '0' ? 8 : 10; 83 acc = any = 0; 84 85 cutoff = ULLONG_MAX / base; 86 cutlim = ULLONG_MAX % base; 87 for ( ; ; c = *s++) { 88 if (c >= '0' && c <= '9') 89 c -= '0'; 90 else if (c >= 'A' && c <= 'Z') 91 c -= 'A' - 10; 92 else if (c >= 'a' && c <= 'z') 93 c -= 'a' - 10; 94 else 95 break; 96 if (c >= base) 97 break; 98 if (any < 0 || acc > cutoff || (acc == cutoff && c > cutlim)) 99 any = -1; 100 else { 101 #ifdef __aarch64__ 102 uint128_t extended = (uint128_t)acc * (unsigned)base; 103 extended += (unsigned)c; 104 105 if (extended > ULLONG_MAX) { 106 any = -1; 107 } else { 108 acc = (unsigned long long)extended; 109 any = 1; 110 } 111 #else 112 any = 1; 113 acc = acc * (unsigned long long)base + (unsigned long long)c; 114 #endif 115 } 116 } 117 if (any < 0) { 118 acc = ULLONG_MAX; 119 } else if (neg) 120 acc = -acc; 121 if (endptr != NULL) 122 *endptr = (char *)(any ? s - 1 : nptr); 123 return (acc); 124 } 125