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 */ 49static 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 61static struct 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 { "options", 1, OPTION_OPTIONS }, 89 { "gunzip", 0, 'z' }, 90 { "gzip", 0, 'z' }, 91 { "help", 0, OPTION_HELP }, 92 { "include", 1, OPTION_INCLUDE }, 93 { "interactive", 0, 'w' }, 94 { "insecure", 0, 'P' }, 95 { "keep-newer-files", 0, OPTION_KEEP_NEWER_FILES }, 96 { "keep-old-files", 0, 'k' }, 97 { "list", 0, 't' }, 98 { "lzma", 0, OPTION_LZMA }, 99 { "modification-time", 0, 'm' }, 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 { "nodump", 0, OPTION_NODUMP }, 107 { "norecurse", 0, 'n' }, 108 { "no-recursion", 0, 'n' }, 109 { "no-same-owner", 0, OPTION_NO_SAME_OWNER }, 110 { "no-same-permissions", 0, OPTION_NO_SAME_PERMISSIONS }, 111 { "null", 0, OPTION_NULL }, 112 { "numeric-owner", 0, OPTION_NUMERIC_OWNER }, 113 { "one-file-system", 0, OPTION_ONE_FILE_SYSTEM }, 114 { "posix", 0, OPTION_POSIX }, 115 { "preserve-permissions", 0, 'p' }, 116 { "read-full-blocks", 0, 'B' }, 117 { "same-owner", 0, OPTION_SAME_OWNER }, 118 { "same-permissions", 0, 'p' }, 119 { "strip-components", 1, OPTION_STRIP_COMPONENTS }, 120 { "to-stdout", 0, 'O' }, 121 { "totals", 0, OPTION_TOTALS }, 122 { "uncompress", 0, 'Z' }, 123 { "unlink", 0, 'U' }, 124 { "unlink-first", 0, 'U' }, 125 { "update", 0, 'u' }, 126 { "use-compress-program", 1, OPTION_USE_COMPRESS_PROGRAM }, 127 { "verbose", 0, 'v' }, 128 { "version", 0, OPTION_VERSION }, 129 { "xz", 0, 'J' }, 130 { NULL, 0, 0 } 131}; 132 133/* 134 * This getopt implementation has two key features that common 135 * getopt_long() implementations lack. Apart from those, it's a 136 * straightforward option parser, considerably simplified by not 137 * needing to support the wealth of exotic getopt_long() features. It 138 * has, of course, been shamelessly tailored for bsdtar. (If you're 139 * looking for a generic getopt_long() implementation for your 140 * project, I recommend Gregory Pietsch's public domain getopt_long() 141 * implementation.) The two additional features are: 142 * 143 * Old-style tar arguments: The original tar implementation treated 144 * the first argument word as a list of single-character option 145 * letters. All arguments follow as separate words. For example, 146 * tar xbf 32 /dev/tape 147 * Here, the "xbf" is three option letters, "32" is the argument for 148 * "b" and "/dev/tape" is the argument for "f". We support this usage 149 * if the first command-line argument does not begin with '-'. We 150 * also allow regular short and long options to follow, e.g., 151 * tar xbf 32 /dev/tape -P --format=pax 152 * 153 * -W long options: There's an obscure GNU convention (only rarely 154 * supported even there) that allows "-W option=argument" as an 155 * alternative way to support long options. This was supported in 156 * early bsdtar as a way to access long options on platforms that did 157 * not support getopt_long() and is preserved here for backwards 158 * compatibility. (Of course, if I'd started with a custom 159 * command-line parser from the beginning, I would have had normal 160 * long option support on every platform so that hack wouldn't have 161 * been necessary. Oh, well. Some mistakes you just have to live 162 * with.) 163 * 164 * TODO: We should be able to use this to pull files and intermingled 165 * options (such as -C) from the command line in write mode. That 166 * will require a little rethinking of the argument handling in 167 * bsdtar.c. 168 * 169 * TODO: If we want to support arbitrary command-line options from -T 170 * input (as GNU tar does), we may need to extend this to handle option 171 * words from sources other than argv/arc. I'm not really sure if I 172 * like that feature of GNU tar, so it's certainly not a priority. 173 */ 174 175int 176bsdtar_getopt(struct bsdtar *bsdtar) 177{ 178 enum { state_start = 0, state_old_tar, state_next_word, 179 state_short, state_long }; 180 static int state = state_start; 181 static char *opt_word; 182 183 const struct option *popt, *match = NULL, *match2 = NULL; 184 const char *p, *long_prefix = "--"; 185 size_t optlength; 186 int opt = '?'; 187 int required = 0; 188 189 bsdtar->optarg = NULL; 190 191 /* First time through, initialize everything. */ 192 if (state == state_start) { 193 /* Skip program name. */ 194 ++bsdtar->argv; 195 --bsdtar->argc; 196 if (*bsdtar->argv == NULL) 197 return (-1); 198 /* Decide between "new style" and "old style" arguments. */ 199 if (bsdtar->argv[0][0] == '-') { 200 state = state_next_word; 201 } else { 202 state = state_old_tar; 203 opt_word = *bsdtar->argv++; 204 --bsdtar->argc; 205 } 206 } 207 208 /* 209 * We're parsing old-style tar arguments 210 */ 211 if (state == state_old_tar) { 212 /* Get the next option character. */ 213 opt = *opt_word++; 214 if (opt == '\0') { 215 /* New-style args can follow old-style. */ 216 state = state_next_word; 217 } else { 218 /* See if it takes an argument. */ 219 p = strchr(short_options, opt); 220 if (p == NULL) 221 return ('?'); 222 if (p[1] == ':') { 223 bsdtar->optarg = *bsdtar->argv; 224 if (bsdtar->optarg == NULL) { 225 lafe_warnc(0, 226 "Option %c requires an argument", 227 opt); 228 return ('?'); 229 } 230 ++bsdtar->argv; 231 --bsdtar->argc; 232 } 233 } 234 } 235 236 /* 237 * We're ready to look at the next word in argv. 238 */ 239 if (state == state_next_word) { 240 /* No more arguments, so no more options. */ 241 if (bsdtar->argv[0] == NULL) 242 return (-1); 243 /* Doesn't start with '-', so no more options. */ 244 if (bsdtar->argv[0][0] != '-') 245 return (-1); 246 /* "--" marks end of options; consume it and return. */ 247 if (strcmp(bsdtar->argv[0], "--") == 0) { 248 ++bsdtar->argv; 249 --bsdtar->argc; 250 return (-1); 251 } 252 /* Get next word for parsing. */ 253 opt_word = *bsdtar->argv++; 254 --bsdtar->argc; 255 if (opt_word[1] == '-') { 256 /* Set up long option parser. */ 257 state = state_long; 258 opt_word += 2; /* Skip leading '--' */ 259 } else { 260 /* Set up short option parser. */ 261 state = state_short; 262 ++opt_word; /* Skip leading '-' */ 263 } 264 } 265 266 /* 267 * We're parsing a group of POSIX-style single-character options. 268 */ 269 if (state == state_short) { 270 /* Peel next option off of a group of short options. */ 271 opt = *opt_word++; 272 if (opt == '\0') { 273 /* End of this group; recurse to get next option. */ 274 state = state_next_word; 275 return bsdtar_getopt(bsdtar); 276 } 277 278 /* Does this option take an argument? */ 279 p = strchr(short_options, opt); 280 if (p == NULL) 281 return ('?'); 282 if (p[1] == ':') 283 required = 1; 284 285 /* If it takes an argument, parse that. */ 286 if (required) { 287 /* If arg is run-in, opt_word already points to it. */ 288 if (opt_word[0] == '\0') { 289 /* Otherwise, pick up the next word. */ 290 opt_word = *bsdtar->argv; 291 if (opt_word == NULL) { 292 lafe_warnc(0, 293 "Option -%c requires an argument", 294 opt); 295 return ('?'); 296 } 297 ++bsdtar->argv; 298 --bsdtar->argc; 299 } 300 if (opt == 'W') { 301 state = state_long; 302 long_prefix = "-W "; /* For clearer errors. */ 303 } else { 304 state = state_next_word; 305 bsdtar->optarg = opt_word; 306 } 307 } 308 } 309 310 /* We're reading a long option, including -W long=arg convention. */ 311 if (state == state_long) { 312 /* After this long option, we'll be starting a new word. */ 313 state = state_next_word; 314 315 /* Option name ends at '=' if there is one. */ 316 p = strchr(opt_word, '='); 317 if (p != NULL) { 318 optlength = (size_t)(p - opt_word); 319 bsdtar->optarg = (char *)(uintptr_t)(p + 1); 320 } else { 321 optlength = strlen(opt_word); 322 } 323 324 /* Search the table for an unambiguous match. */ 325 for (popt = tar_longopts; popt->name != NULL; popt++) { 326 /* Short-circuit if first chars don't match. */ 327 if (popt->name[0] != opt_word[0]) 328 continue; 329 /* If option is a prefix of name in table, record it.*/ 330 if (strncmp(opt_word, popt->name, optlength) == 0) { 331 match2 = match; /* Record up to two matches. */ 332 match = popt; 333 /* If it's an exact match, we're done. */ 334 if (strlen(popt->name) == optlength) { 335 match2 = NULL; /* Forget the others. */ 336 break; 337 } 338 } 339 } 340 341 /* Fail if there wasn't a unique match. */ 342 if (match == NULL) { 343 lafe_warnc(0, 344 "Option %s%s is not supported", 345 long_prefix, opt_word); 346 return ('?'); 347 } 348 if (match2 != NULL) { 349 lafe_warnc(0, 350 "Ambiguous option %s%s (matches --%s and --%s)", 351 long_prefix, opt_word, match->name, match2->name); 352 return ('?'); 353 } 354 355 /* We've found a unique match; does it need an argument? */ 356 if (match->required) { 357 /* Argument required: get next word if necessary. */ 358 if (bsdtar->optarg == NULL) { 359 bsdtar->optarg = *bsdtar->argv; 360 if (bsdtar->optarg == NULL) { 361 lafe_warnc(0, 362 "Option %s%s requires an argument", 363 long_prefix, match->name); 364 return ('?'); 365 } 366 ++bsdtar->argv; 367 --bsdtar->argc; 368 } 369 } else { 370 /* Argument forbidden: fail if there is one. */ 371 if (bsdtar->optarg != NULL) { 372 lafe_warnc(0, 373 "Option %s%s does not allow an argument", 374 long_prefix, match->name); 375 return ('?'); 376 } 377 } 378 return (match->equivalent); 379 } 380 381 return (opt); 382} 383