1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2007 Eric Anderson <anderson@FreeBSD.org> 5 * Copyright (c) 2007 Pawel Jakub Dawidek <pjd@FreeBSD.org> 6 * Copyright (c) 2025 Dag-Erling Smørgrav <des@FreeBSD.org> 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS 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 AUTHORS 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 <inttypes.h> 36 #include <libutil.h> 37 #include <stdbool.h> 38 #include <stdint.h> 39 40 static int 41 expand_impl(const char *buf, uint64_t *num, bool *neg) 42 { 43 char *endptr; 44 uintmax_t number; 45 unsigned int shift; 46 int serrno; 47 48 /* 49 * Skip whitespace and optional sign. 50 */ 51 while (isspace((unsigned char)*buf)) 52 buf++; 53 if (*buf == '-') { 54 *neg = true; 55 buf++; 56 } else { 57 *neg = false; 58 if (*buf == '+') 59 buf++; 60 } 61 62 /* 63 * The next character should be the first digit of the number. If 64 * we don't enforce this ourselves, strtoumax() will allow further 65 * whitespace and a (second?) sign. 66 */ 67 if (!isdigit((unsigned char)*buf)) { 68 errno = EINVAL; 69 return (-1); 70 } 71 72 serrno = errno; 73 errno = 0; 74 number = strtoumax(buf, &endptr, 0); 75 if (errno != 0) 76 return (-1); 77 errno = serrno; 78 79 switch (tolower((unsigned char)*endptr)) { 80 case 'e': 81 shift = 60; 82 endptr++; 83 break; 84 case 'p': 85 shift = 50; 86 endptr++; 87 break; 88 case 't': 89 shift = 40; 90 endptr++; 91 break; 92 case 'g': 93 shift = 30; 94 endptr++; 95 break; 96 case 'm': 97 shift = 20; 98 endptr++; 99 break; 100 case 'k': 101 shift = 10; 102 endptr++; 103 break; 104 default: 105 shift = 0; 106 } 107 108 /* 109 * Treat 'b' as an ignored suffix for all unit except 'b', 110 * otherwise there should be no remaining character(s). 111 */ 112 if (tolower((unsigned char)*endptr) == 'b') 113 endptr++; 114 if (*endptr != '\0') { 115 errno = EINVAL; 116 return (-1); 117 } 118 119 /* 120 * Apply the shift and check for overflow. 121 */ 122 if ((number << shift) >> shift != number) { 123 /* Overflow */ 124 errno = ERANGE; 125 return (-1); 126 } 127 number <<= shift; 128 129 *num = number; 130 return (0); 131 } 132 133 int 134 (expand_number)(const char *buf, int64_t *num) 135 { 136 uint64_t number; 137 bool neg; 138 139 /* 140 * Parse the number. 141 */ 142 if (expand_impl(buf, &number, &neg) != 0) 143 return (-1); 144 145 /* 146 * Apply the sign and check for overflow. 147 */ 148 if (neg) { 149 if (number > 0x8000000000000000LLU /* -INT64_MIN */) { 150 errno = ERANGE; 151 return (-1); 152 } 153 *num = -number; 154 } else { 155 if (number > INT64_MAX) { 156 errno = ERANGE; 157 return (-1); 158 } 159 *num = number; 160 } 161 162 return (0); 163 } 164 165 int 166 expand_unsigned(const char *buf, uint64_t *num) 167 { 168 uint64_t number; 169 bool neg; 170 171 /* 172 * Parse the number. 173 */ 174 if (expand_impl(buf, &number, &neg) != 0) 175 return (-1); 176 177 /* 178 * Negative numbers are out of range. 179 */ 180 if (neg && number > 0) { 181 errno = ERANGE; 182 return (-1); 183 } 184 185 *num = number; 186 return (0); 187 } 188