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