1 /* A more useful interface to strtol. 2 3 Copyright (C) 1995-1996, 1998-2001, 2003-2007, 2009-2020 Free Software 4 Foundation, Inc. 5 6 This program is free software: you can redistribute it and/or modify 7 it under the terms of the GNU General Public License as published by 8 the Free Software Foundation; either version 3 of the License, or 9 (at your option) any later version. 10 11 This program is distributed in the hope that it will be useful, 12 but WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 GNU General Public License for more details. 15 16 You should have received a copy of the GNU General Public License 17 along with this program. If not, see <https://www.gnu.org/licenses/>. */ 18 19 /* Written by Jim Meyering. */ 20 21 #ifndef __strtol 22 # define __strtol strtol 23 # define __strtol_t long int 24 # define __xstrtol xstrtol 25 # define STRTOL_T_MINIMUM LONG_MIN 26 # define STRTOL_T_MAXIMUM LONG_MAX 27 #endif 28 29 #include <config.h> 30 31 #include "xstrtol.h" 32 33 /* Some pre-ANSI implementations (e.g. SunOS 4) 34 need stderr defined if assertion checking is enabled. */ 35 #include <stdio.h> 36 37 #include <ctype.h> 38 #include <errno.h> 39 #include <limits.h> 40 #include <stdlib.h> 41 #include <string.h> 42 43 #include "assure.h" 44 45 #define TYPE_SIGNED(t) (! ((t) 0 < (t) -1)) 46 47 static strtol_error 48 bkm_scale (__strtol_t *x, int scale_factor) 49 { 50 if (TYPE_SIGNED (__strtol_t) && *x < STRTOL_T_MINIMUM / scale_factor) 51 { 52 *x = STRTOL_T_MINIMUM; 53 return LONGINT_OVERFLOW; 54 } 55 if (STRTOL_T_MAXIMUM / scale_factor < *x) 56 { 57 *x = STRTOL_T_MAXIMUM; 58 return LONGINT_OVERFLOW; 59 } 60 *x *= scale_factor; 61 return LONGINT_OK; 62 } 63 64 static strtol_error 65 bkm_scale_by_power (__strtol_t *x, int base, int power) 66 { 67 strtol_error err = LONGINT_OK; 68 while (power--) 69 err |= bkm_scale (x, base); 70 return err; 71 } 72 73 /* FIXME: comment. */ 74 75 strtol_error 76 __xstrtol (const char *s, char **ptr, int strtol_base, 77 __strtol_t *val, const char *valid_suffixes) 78 { 79 char *t_ptr; 80 char **p; 81 __strtol_t tmp; 82 strtol_error err = LONGINT_OK; 83 84 assure (0 <= strtol_base && strtol_base <= 36); 85 86 p = (ptr ? ptr : &t_ptr); 87 88 errno = 0; 89 90 if (! TYPE_SIGNED (__strtol_t)) 91 { 92 const char *q = s; 93 unsigned char ch = *q; 94 while (isspace (ch)) 95 ch = *++q; 96 if (ch == '-') 97 return LONGINT_INVALID; 98 } 99 100 tmp = __strtol (s, p, strtol_base); 101 102 if (*p == s) 103 { 104 /* If there is no number but there is a valid suffix, assume the 105 number is 1. The string is invalid otherwise. */ 106 if (valid_suffixes && **p && strchr (valid_suffixes, **p)) 107 tmp = 1; 108 else 109 return LONGINT_INVALID; 110 } 111 else if (errno != 0) 112 { 113 if (errno != ERANGE) 114 return LONGINT_INVALID; 115 err = LONGINT_OVERFLOW; 116 } 117 118 /* Let valid_suffixes == NULL mean "allow any suffix". */ 119 /* FIXME: update all callers except the ones that allow suffixes 120 after the number, changing last parameter NULL to "". */ 121 if (!valid_suffixes) 122 { 123 *val = tmp; 124 return err; 125 } 126 127 if (**p != '\0') 128 { 129 int base = 1024; 130 int suffixes = 1; 131 strtol_error overflow; 132 133 if (!strchr (valid_suffixes, **p)) 134 { 135 *val = tmp; 136 return err | LONGINT_INVALID_SUFFIX_CHAR; 137 } 138 139 switch (**p) 140 { 141 case 'E': case 'G': case 'g': case 'k': case 'K': case 'M': case 'm': 142 case 'P': case 'T': case 't': case 'Y': case 'Z': 143 144 /* The "valid suffix" '0' is a special flag meaning that 145 an optional second suffix is allowed, which can change 146 the base. A suffix "B" (e.g. "100MB") stands for a power 147 of 1000, whereas a suffix "iB" (e.g. "100MiB") stands for 148 a power of 1024. If no suffix (e.g. "100M"), assume 149 power-of-1024. */ 150 151 if (strchr (valid_suffixes, '0')) 152 switch (p[0][1]) 153 { 154 case 'i': 155 if (p[0][2] == 'B') 156 suffixes += 2; 157 break; 158 159 case 'B': 160 case 'D': /* 'D' is obsolescent */ 161 base = 1000; 162 suffixes++; 163 break; 164 } 165 } 166 167 switch (**p) 168 { 169 case 'b': 170 overflow = bkm_scale (&tmp, 512); 171 break; 172 173 case 'B': 174 /* This obsolescent first suffix is distinct from the 'B' 175 second suffix above. E.g., 'tar -L 1000B' means change 176 the tape after writing 1000 KiB of data. */ 177 overflow = bkm_scale (&tmp, 1024); 178 break; 179 180 case 'c': 181 overflow = LONGINT_OK; 182 break; 183 184 case 'E': /* exa or exbi */ 185 overflow = bkm_scale_by_power (&tmp, base, 6); 186 break; 187 188 case 'G': /* giga or gibi */ 189 case 'g': /* 'g' is undocumented; for compatibility only */ 190 overflow = bkm_scale_by_power (&tmp, base, 3); 191 break; 192 193 case 'k': /* kilo */ 194 case 'K': /* kibi */ 195 overflow = bkm_scale_by_power (&tmp, base, 1); 196 break; 197 198 case 'M': /* mega or mebi */ 199 case 'm': /* 'm' is undocumented; for compatibility only */ 200 overflow = bkm_scale_by_power (&tmp, base, 2); 201 break; 202 203 case 'P': /* peta or pebi */ 204 overflow = bkm_scale_by_power (&tmp, base, 5); 205 break; 206 207 case 'T': /* tera or tebi */ 208 case 't': /* 't' is undocumented; for compatibility only */ 209 overflow = bkm_scale_by_power (&tmp, base, 4); 210 break; 211 212 case 'w': 213 overflow = bkm_scale (&tmp, 2); 214 break; 215 216 case 'Y': /* yotta or 2**80 */ 217 overflow = bkm_scale_by_power (&tmp, base, 8); 218 break; 219 220 case 'Z': /* zetta or 2**70 */ 221 overflow = bkm_scale_by_power (&tmp, base, 7); 222 break; 223 224 default: 225 *val = tmp; 226 return err | LONGINT_INVALID_SUFFIX_CHAR; 227 } 228 229 err |= overflow; 230 *p += suffixes; 231 if (**p) 232 err |= LONGINT_INVALID_SUFFIX_CHAR; 233 } 234 235 *val = tmp; 236 return err; 237 } 238