1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2003-2008 Tim Kientzle 5 * All rights reserved. 6 */ 7 8 /* 9 * Command line parser for tar. 10 */ 11 12 #include "bsdtar_platform.h" 13 14 #ifdef HAVE_ERRNO_H 15 #include <errno.h> 16 #endif 17 #ifdef HAVE_STDLIB_H 18 #include <stdlib.h> 19 #endif 20 #ifdef HAVE_STRING_H 21 #include <string.h> 22 #endif 23 24 #include "bsdtar.h" 25 #include "err.h" 26 27 /* 28 * Short options for tar. Please keep this sorted. 29 */ 30 static const char *short_options 31 = "aBb:C:cf:HhI:JjkLlmnOoPpqrSs:T:tUuvW:wX:xyZz"; 32 33 /* 34 * Long options for tar. Please keep this list sorted. 35 * 36 * The symbolic names for options that lack a short equivalent are 37 * defined in bsdtar.h. Also note that so far I've found no need 38 * to support optional arguments to long options. That would be 39 * a small change to the code below. 40 */ 41 42 static const struct bsdtar_option { 43 const char *name; 44 int required; /* 1 if this option requires an argument. */ 45 int equivalent; /* Equivalent short option. */ 46 } tar_longopts[] = { 47 { "absolute-paths", 0, 'P' }, 48 { "append", 0, 'r' }, 49 { "acls", 0, OPTION_ACLS }, 50 { "auto-compress", 0, 'a' }, 51 { "b64encode", 0, OPTION_B64ENCODE }, 52 { "block-size", 1, 'b' }, 53 { "blocking-factor", 1, 'b' }, 54 { "bunzip2", 0, 'j' }, 55 { "bzip", 0, 'j' }, 56 { "bzip2", 0, 'j' }, 57 { "cd", 1, 'C' }, 58 { "check-links", 0, OPTION_CHECK_LINKS }, 59 { "chroot", 0, OPTION_CHROOT }, 60 { "clamp-mtime", 0, OPTION_CLAMP_MTIME }, 61 { "clear-nochange-fflags", 0, OPTION_CLEAR_NOCHANGE_FFLAGS }, 62 { "compress", 0, 'Z' }, 63 { "confirmation", 0, 'w' }, 64 { "create", 0, 'c' }, 65 { "dereference", 0, 'L' }, 66 { "directory", 1, 'C' }, 67 { "disable-copyfile", 0, OPTION_NO_MAC_METADATA }, 68 { "exclude", 1, OPTION_EXCLUDE }, 69 { "exclude-from", 1, 'X' }, 70 { "exclude-vcs", 0, OPTION_EXCLUDE_VCS }, 71 { "extract", 0, 'x' }, 72 { "fast-read", 0, 'q' }, 73 { "fflags", 0, OPTION_FFLAGS }, 74 { "file", 1, 'f' }, 75 { "files-from", 1, 'T' }, 76 { "format", 1, OPTION_FORMAT }, 77 { "gid", 1, OPTION_GID }, 78 { "gname", 1, OPTION_GNAME }, 79 { "group", 1, OPTION_GROUP }, 80 { "grzip", 0, OPTION_GRZIP }, 81 { "gunzip", 0, 'z' }, 82 { "gzip", 0, 'z' }, 83 { "help", 0, OPTION_HELP }, 84 { "hfsCompression", 0, OPTION_HFS_COMPRESSION }, 85 { "ignore-zeros", 0, OPTION_IGNORE_ZEROS }, 86 { "include", 1, OPTION_INCLUDE }, 87 { "insecure", 0, 'P' }, 88 { "interactive", 0, 'w' }, 89 { "keep-newer-files", 0, OPTION_KEEP_NEWER_FILES }, 90 { "keep-old-files", 0, 'k' }, 91 { "list", 0, 't' }, 92 { "lrzip", 0, OPTION_LRZIP }, 93 { "lz4", 0, OPTION_LZ4 }, 94 { "lzip", 0, OPTION_LZIP }, 95 { "lzma", 0, OPTION_LZMA }, 96 { "lzop", 0, OPTION_LZOP }, 97 { "mac-metadata", 0, OPTION_MAC_METADATA }, 98 { "modification-time", 0, 'm' }, 99 { "mtime", 1, OPTION_MTIME }, 100 { "newer", 1, OPTION_NEWER_CTIME }, 101 { "newer-ctime", 1, OPTION_NEWER_CTIME }, 102 { "newer-ctime-than", 1, OPTION_NEWER_CTIME_THAN }, 103 { "newer-mtime", 1, OPTION_NEWER_MTIME }, 104 { "newer-mtime-than", 1, OPTION_NEWER_MTIME_THAN }, 105 { "newer-than", 1, OPTION_NEWER_CTIME_THAN }, 106 { "no-acls", 0, OPTION_NO_ACLS }, 107 { "no-fflags", 0, OPTION_NO_FFLAGS }, 108 { "no-mac-metadata", 0, OPTION_NO_MAC_METADATA }, 109 { "no-read-sparse", 0, OPTION_NO_READ_SPARSE }, 110 { "no-recursion", 0, 'n' }, 111 { "no-safe-writes", 0, OPTION_NO_SAFE_WRITES }, 112 { "no-same-owner", 0, OPTION_NO_SAME_OWNER }, 113 { "no-same-permissions", 0, OPTION_NO_SAME_PERMISSIONS }, 114 { "no-xattr", 0, OPTION_NO_XATTRS }, 115 { "no-xattrs", 0, OPTION_NO_XATTRS }, 116 { "nodump", 0, OPTION_NODUMP }, 117 { "nopreserveHFSCompression",0, OPTION_NOPRESERVE_HFS_COMPRESSION }, 118 { "norecurse", 0, 'n' }, 119 { "null", 0, OPTION_NULL }, 120 { "numeric-owner", 0, OPTION_NUMERIC_OWNER }, 121 { "older", 1, OPTION_OLDER_CTIME }, 122 { "older-ctime", 1, OPTION_OLDER_CTIME }, 123 { "older-ctime-than", 1, OPTION_OLDER_CTIME_THAN }, 124 { "older-mtime", 1, OPTION_OLDER_MTIME }, 125 { "older-mtime-than", 1, OPTION_OLDER_MTIME_THAN }, 126 { "older-than", 1, OPTION_OLDER_CTIME_THAN }, 127 { "one-file-system", 0, OPTION_ONE_FILE_SYSTEM }, 128 { "options", 1, OPTION_OPTIONS }, 129 { "owner", 1, OPTION_OWNER }, 130 { "passphrase", 1, OPTION_PASSPHRASE }, 131 { "posix", 0, OPTION_POSIX }, 132 { "preserve-permissions", 0, 'p' }, 133 { "read-full-blocks", 0, 'B' }, 134 { "read-sparse", 0, OPTION_READ_SPARSE }, 135 { "safe-writes", 0, OPTION_SAFE_WRITES }, 136 { "same-owner", 0, OPTION_SAME_OWNER }, 137 { "same-permissions", 0, 'p' }, 138 { "strip-components", 1, OPTION_STRIP_COMPONENTS }, 139 { "to-stdout", 0, 'O' }, 140 { "totals", 0, OPTION_TOTALS }, 141 { "uid", 1, OPTION_UID }, 142 { "uname", 1, OPTION_UNAME }, 143 { "uncompress", 0, 'Z' }, 144 { "unlink", 0, 'U' }, 145 { "unlink-first", 0, 'U' }, 146 { "update", 0, 'u' }, 147 { "use-compress-program", 1, OPTION_USE_COMPRESS_PROGRAM }, 148 { "uuencode", 0, OPTION_UUENCODE }, 149 { "verbose", 0, 'v' }, 150 { "version", 0, OPTION_VERSION }, 151 { "xattrs", 0, OPTION_XATTRS }, 152 { "xz", 0, 'J' }, 153 { "zstd", 0, OPTION_ZSTD }, 154 { NULL, 0, 0 } 155 }; 156 157 /* 158 * This getopt implementation has two key features that common 159 * getopt_long() implementations lack. Apart from those, it's a 160 * straightforward option parser, considerably simplified by not 161 * needing to support the wealth of exotic getopt_long() features. It 162 * has, of course, been shamelessly tailored for bsdtar. (If you're 163 * looking for a generic getopt_long() implementation for your 164 * project, I recommend Gregory Pietsch's public domain getopt_long() 165 * implementation.) The two additional features are: 166 * 167 * Old-style tar arguments: The original tar implementation treated 168 * the first argument word as a list of single-character option 169 * letters. All arguments follow as separate words. For example, 170 * tar xbf 32 /dev/tape 171 * Here, the "xbf" is three option letters, "32" is the argument for 172 * "b" and "/dev/tape" is the argument for "f". We support this usage 173 * if the first command-line argument does not begin with '-'. We 174 * also allow regular short and long options to follow, e.g., 175 * tar xbf 32 /dev/tape -P --format=pax 176 * 177 * -W long options: There's an obscure GNU convention (only rarely 178 * supported even there) that allows "-W option=argument" as an 179 * alternative way to support long options. This was supported in 180 * early bsdtar as a way to access long options on platforms that did 181 * not support getopt_long() and is preserved here for backwards 182 * compatibility. (Of course, if I'd started with a custom 183 * command-line parser from the beginning, I would have had normal 184 * long option support on every platform so that hack wouldn't have 185 * been necessary. Oh, well. Some mistakes you just have to live 186 * with.) 187 * 188 * TODO: We should be able to use this to pull files and intermingled 189 * options (such as -C) from the command line in write mode. That 190 * will require a little rethinking of the argument handling in 191 * bsdtar.c. 192 * 193 * TODO: If we want to support arbitrary command-line options from -T 194 * input (as GNU tar does), we may need to extend this to handle option 195 * words from sources other than argv/argc. I'm not really sure if I 196 * like that feature of GNU tar, so it's certainly not a priority. 197 */ 198 199 int 200 bsdtar_getopt(struct bsdtar *bsdtar) 201 { 202 enum { state_start = 0, state_old_tar, state_next_word, 203 state_short, state_long }; 204 205 const struct bsdtar_option *popt, *match, *match2; 206 const char *p, *long_prefix; 207 size_t optlength; 208 int opt; 209 int required; 210 211 again: 212 match = NULL; 213 match2 = NULL; 214 long_prefix = "--"; 215 opt = '?'; 216 required = 0; 217 bsdtar->argument = NULL; 218 219 /* First time through, initialize everything. */ 220 if (bsdtar->getopt_state == state_start) { 221 /* Skip program name. */ 222 ++bsdtar->argv; 223 --bsdtar->argc; 224 if (*bsdtar->argv == NULL) 225 return (-1); 226 /* Decide between "new style" and "old style" arguments. */ 227 if (bsdtar->argv[0][0] == '-') { 228 bsdtar->getopt_state = state_next_word; 229 } else { 230 bsdtar->getopt_state = state_old_tar; 231 bsdtar->getopt_word = *bsdtar->argv++; 232 --bsdtar->argc; 233 } 234 } 235 236 /* 237 * We're parsing old-style tar arguments 238 */ 239 if (bsdtar->getopt_state == state_old_tar) { 240 /* Get the next option character. */ 241 opt = *bsdtar->getopt_word++; 242 if (opt == '\0') { 243 /* New-style args can follow old-style. */ 244 bsdtar->getopt_state = state_next_word; 245 } else { 246 /* See if it takes an argument. */ 247 p = strchr(short_options, opt); 248 if (p == NULL) 249 return ('?'); 250 if (p[1] == ':') { 251 bsdtar->argument = *bsdtar->argv; 252 if (bsdtar->argument == NULL) { 253 lafe_warnc(0, 254 "Option %c requires an argument", 255 opt); 256 return ('?'); 257 } 258 ++bsdtar->argv; 259 --bsdtar->argc; 260 } 261 } 262 } 263 264 /* 265 * We're ready to look at the next word in argv. 266 */ 267 if (bsdtar->getopt_state == state_next_word) { 268 /* No more arguments, so no more options. */ 269 if (bsdtar->argv[0] == NULL) 270 return (-1); 271 /* Doesn't start with '-', so no more options. */ 272 if (bsdtar->argv[0][0] != '-') 273 return (-1); 274 /* "--" marks end of options; consume it and return. */ 275 if (strcmp(bsdtar->argv[0], "--") == 0) { 276 ++bsdtar->argv; 277 --bsdtar->argc; 278 return (-1); 279 } 280 /* Get next word for parsing. */ 281 bsdtar->getopt_word = *bsdtar->argv++; 282 --bsdtar->argc; 283 if (bsdtar->getopt_word[1] == '-') { 284 /* Set up long option parser. */ 285 bsdtar->getopt_state = state_long; 286 bsdtar->getopt_word += 2; /* Skip leading '--' */ 287 } else { 288 /* Set up short option parser. */ 289 bsdtar->getopt_state = state_short; 290 ++bsdtar->getopt_word; /* Skip leading '-' */ 291 } 292 } 293 294 /* 295 * We're parsing a group of POSIX-style single-character options. 296 */ 297 if (bsdtar->getopt_state == state_short) { 298 /* Peel next option off of a group of short options. */ 299 opt = *bsdtar->getopt_word++; 300 if (opt == '\0') { 301 /* End of this group; recurse to get next option. */ 302 bsdtar->getopt_state = state_next_word; 303 goto again; 304 } 305 306 /* Does this option take an argument? */ 307 p = strchr(short_options, opt); 308 if (p == NULL) 309 return ('?'); 310 if (p[1] == ':') 311 required = 1; 312 313 /* If it takes an argument, parse that. */ 314 if (required) { 315 /* If arg is run-in, bsdtar->getopt_word already points to it. */ 316 if (bsdtar->getopt_word[0] == '\0') { 317 /* Otherwise, pick up the next word. */ 318 bsdtar->getopt_word = *bsdtar->argv; 319 if (bsdtar->getopt_word == NULL) { 320 lafe_warnc(0, 321 "Option -%c requires an argument", 322 opt); 323 return ('?'); 324 } 325 ++bsdtar->argv; 326 --bsdtar->argc; 327 } 328 if (opt == 'W') { 329 bsdtar->getopt_state = state_long; 330 long_prefix = "-W "; /* For clearer errors. */ 331 } else { 332 bsdtar->getopt_state = state_next_word; 333 bsdtar->argument = bsdtar->getopt_word; 334 } 335 } 336 } 337 338 /* We're reading a long option, including -W long=arg convention. */ 339 if (bsdtar->getopt_state == state_long) { 340 /* After this long option, we'll be starting a new word. */ 341 bsdtar->getopt_state = state_next_word; 342 343 /* Option name ends at '=' if there is one. */ 344 p = strchr(bsdtar->getopt_word, '='); 345 if (p != NULL) { 346 optlength = (size_t)(p - bsdtar->getopt_word); 347 bsdtar->argument = (char *)(uintptr_t)(p + 1); 348 } else { 349 optlength = strlen(bsdtar->getopt_word); 350 } 351 352 /* Search the table for an unambiguous match. */ 353 for (popt = tar_longopts; popt->name != NULL; popt++) { 354 /* Short-circuit if first chars don't match. */ 355 if (popt->name[0] != bsdtar->getopt_word[0]) 356 continue; 357 /* If option is a prefix of name in table, record it.*/ 358 if (strncmp(bsdtar->getopt_word, popt->name, optlength) == 0) { 359 match2 = match; /* Record up to two matches. */ 360 match = popt; 361 /* If it's an exact match, we're done. */ 362 if (strlen(popt->name) == optlength) { 363 match2 = NULL; /* Forget the others. */ 364 break; 365 } 366 } 367 } 368 369 /* Fail if there wasn't a unique match. */ 370 if (match == NULL) { 371 lafe_warnc(0, 372 "Option %s%s is not supported", 373 long_prefix, bsdtar->getopt_word); 374 return ('?'); 375 } 376 if (match2 != NULL) { 377 lafe_warnc(0, 378 "Ambiguous option %s%s (matches --%s and --%s)", 379 long_prefix, bsdtar->getopt_word, match->name, match2->name); 380 return ('?'); 381 } 382 383 /* We've found a unique match; does it need an argument? */ 384 if (match->required) { 385 /* Argument required: get next word if necessary. */ 386 if (bsdtar->argument == NULL) { 387 bsdtar->argument = *bsdtar->argv; 388 if (bsdtar->argument == NULL) { 389 lafe_warnc(0, 390 "Option %s%s requires an argument", 391 long_prefix, match->name); 392 return ('?'); 393 } 394 ++bsdtar->argv; 395 --bsdtar->argc; 396 } 397 } else { 398 /* Argument forbidden: fail if there is one. */ 399 if (bsdtar->argument != NULL) { 400 lafe_warnc(0, 401 "Option %s%s does not allow an argument", 402 long_prefix, match->name); 403 return ('?'); 404 } 405 } 406 return (match->equivalent); 407 } 408 409 return (opt); 410 } 411