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 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 { "exclude", 1, OPTION_EXCLUDE }, 81 { "exclude-from", 1, 'X' }, 82 { "extract", 0, 'x' }, 83 { "fast-read", 0, 'q' }, 84 { "file", 1, 'f' }, 85 { "files-from", 1, 'T' }, 86 { "format", 1, OPTION_FORMAT }, 87 { "options", 1, OPTION_OPTIONS }, 88 { "gunzip", 0, 'z' }, 89 { "gzip", 0, 'z' }, 90 { "help", 0, OPTION_HELP }, 91 { "include", 1, OPTION_INCLUDE }, 92 { "interactive", 0, 'w' }, 93 { "insecure", 0, 'P' }, 94 { "keep-newer-files", 0, OPTION_KEEP_NEWER_FILES }, 95 { "keep-old-files", 0, 'k' }, 96 { "list", 0, 't' }, 97 { "lzma", 0, OPTION_LZMA }, 98 { "modification-time", 0, 'm' }, 99 { "newer", 1, OPTION_NEWER_CTIME }, 100 { "newer-ctime", 1, OPTION_NEWER_CTIME }, 101 { "newer-ctime-than", 1, OPTION_NEWER_CTIME_THAN }, 102 { "newer-mtime", 1, OPTION_NEWER_MTIME }, 103 { "newer-mtime-than", 1, OPTION_NEWER_MTIME_THAN }, 104 { "newer-than", 1, OPTION_NEWER_CTIME_THAN }, 105 { "nodump", 0, OPTION_NODUMP }, 106 { "norecurse", 0, 'n' }, 107 { "no-recursion", 0, 'n' }, 108 { "no-same-owner", 0, OPTION_NO_SAME_OWNER }, 109 { "no-same-permissions", 0, OPTION_NO_SAME_PERMISSIONS }, 110 { "null", 0, OPTION_NULL }, 111 { "numeric-owner", 0, OPTION_NUMERIC_OWNER }, 112 { "one-file-system", 0, OPTION_ONE_FILE_SYSTEM }, 113 { "posix", 0, OPTION_POSIX }, 114 { "preserve-permissions", 0, 'p' }, 115 { "read-full-blocks", 0, 'B' }, 116 { "same-owner", 0, OPTION_SAME_OWNER }, 117 { "same-permissions", 0, 'p' }, 118 { "strip-components", 1, OPTION_STRIP_COMPONENTS }, 119 { "to-stdout", 0, 'O' }, 120 { "totals", 0, OPTION_TOTALS }, 121 { "uncompress", 0, 'Z' }, 122 { "unlink", 0, 'U' }, 123 { "unlink-first", 0, 'U' }, 124 { "update", 0, 'u' }, 125 { "use-compress-program", 1, OPTION_USE_COMPRESS_PROGRAM }, 126 { "verbose", 0, 'v' }, 127 { "version", 0, OPTION_VERSION }, 128 { "xz", 0, 'J' }, 129 { NULL, 0, 0 } 130 }; 131 132 /* 133 * This getopt implementation has two key features that common 134 * getopt_long() implementations lack. Apart from those, it's a 135 * straightforward option parser, considerably simplified by not 136 * needing to support the wealth of exotic getopt_long() features. It 137 * has, of course, been shamelessly tailored for bsdtar. (If you're 138 * looking for a generic getopt_long() implementation for your 139 * project, I recommend Gregory Pietsch's public domain getopt_long() 140 * implementation.) The two additional features are: 141 * 142 * Old-style tar arguments: The original tar implementation treated 143 * the first argument word as a list of single-character option 144 * letters. All arguments follow as separate words. For example, 145 * tar xbf 32 /dev/tape 146 * Here, the "xbf" is three option letters, "32" is the argument for 147 * "b" and "/dev/tape" is the argument for "f". We support this usage 148 * if the first command-line argument does not begin with '-'. We 149 * also allow regular short and long options to follow, e.g., 150 * tar xbf 32 /dev/tape -P --format=pax 151 * 152 * -W long options: There's an obscure GNU convention (only rarely 153 * supported even there) that allows "-W option=argument" as an 154 * alternative way to support long options. This was supported in 155 * early bsdtar as a way to access long options on platforms that did 156 * not support getopt_long() and is preserved here for backwards 157 * compatibility. (Of course, if I'd started with a custom 158 * command-line parser from the beginning, I would have had normal 159 * long option support on every platform so that hack wouldn't have 160 * been necessary. Oh, well. Some mistakes you just have to live 161 * with.) 162 * 163 * TODO: We should be able to use this to pull files and intermingled 164 * options (such as -C) from the command line in write mode. That 165 * will require a little rethinking of the argument handling in 166 * bsdtar.c. 167 * 168 * TODO: If we want to support arbitrary command-line options from -T 169 * input (as GNU tar does), we may need to extend this to handle option 170 * words from sources other than argv/arc. I'm not really sure if I 171 * like that feature of GNU tar, so it's certainly not a priority. 172 */ 173 174 int 175 bsdtar_getopt(struct bsdtar *bsdtar) 176 { 177 enum { state_start = 0, state_old_tar, state_next_word, 178 state_short, state_long }; 179 static int state = state_start; 180 static char *opt_word; 181 182 const struct option *popt, *match = NULL, *match2 = NULL; 183 const char *p, *long_prefix = "--"; 184 size_t optlength; 185 int opt = '?'; 186 int required = 0; 187 188 bsdtar->optarg = NULL; 189 190 /* First time through, initialize everything. */ 191 if (state == state_start) { 192 /* Skip program name. */ 193 ++bsdtar->argv; 194 --bsdtar->argc; 195 if (*bsdtar->argv == NULL) 196 return (-1); 197 /* Decide between "new style" and "old style" arguments. */ 198 if (bsdtar->argv[0][0] == '-') { 199 state = state_next_word; 200 } else { 201 state = state_old_tar; 202 opt_word = *bsdtar->argv++; 203 --bsdtar->argc; 204 } 205 } 206 207 /* 208 * We're parsing old-style tar arguments 209 */ 210 if (state == state_old_tar) { 211 /* Get the next option character. */ 212 opt = *opt_word++; 213 if (opt == '\0') { 214 /* New-style args can follow old-style. */ 215 state = state_next_word; 216 } else { 217 /* See if it takes an argument. */ 218 p = strchr(short_options, opt); 219 if (p == NULL) 220 return ('?'); 221 if (p[1] == ':') { 222 bsdtar->optarg = *bsdtar->argv; 223 if (bsdtar->optarg == NULL) { 224 lafe_warnc(0, 225 "Option %c requires an argument", 226 opt); 227 return ('?'); 228 } 229 ++bsdtar->argv; 230 --bsdtar->argc; 231 } 232 } 233 } 234 235 /* 236 * We're ready to look at the next word in argv. 237 */ 238 if (state == state_next_word) { 239 /* No more arguments, so no more options. */ 240 if (bsdtar->argv[0] == NULL) 241 return (-1); 242 /* Doesn't start with '-', so no more options. */ 243 if (bsdtar->argv[0][0] != '-') 244 return (-1); 245 /* "--" marks end of options; consume it and return. */ 246 if (strcmp(bsdtar->argv[0], "--") == 0) { 247 ++bsdtar->argv; 248 --bsdtar->argc; 249 return (-1); 250 } 251 /* Get next word for parsing. */ 252 opt_word = *bsdtar->argv++; 253 --bsdtar->argc; 254 if (opt_word[1] == '-') { 255 /* Set up long option parser. */ 256 state = state_long; 257 opt_word += 2; /* Skip leading '--' */ 258 } else { 259 /* Set up short option parser. */ 260 state = state_short; 261 ++opt_word; /* Skip leading '-' */ 262 } 263 } 264 265 /* 266 * We're parsing a group of POSIX-style single-character options. 267 */ 268 if (state == state_short) { 269 /* Peel next option off of a group of short options. */ 270 opt = *opt_word++; 271 if (opt == '\0') { 272 /* End of this group; recurse to get next option. */ 273 state = state_next_word; 274 return bsdtar_getopt(bsdtar); 275 } 276 277 /* Does this option take an argument? */ 278 p = strchr(short_options, opt); 279 if (p == NULL) 280 return ('?'); 281 if (p[1] == ':') 282 required = 1; 283 284 /* If it takes an argument, parse that. */ 285 if (required) { 286 /* If arg is run-in, opt_word already points to it. */ 287 if (opt_word[0] == '\0') { 288 /* Otherwise, pick up the next word. */ 289 opt_word = *bsdtar->argv; 290 if (opt_word == NULL) { 291 lafe_warnc(0, 292 "Option -%c requires an argument", 293 opt); 294 return ('?'); 295 } 296 ++bsdtar->argv; 297 --bsdtar->argc; 298 } 299 if (opt == 'W') { 300 state = state_long; 301 long_prefix = "-W "; /* For clearer errors. */ 302 } else { 303 state = state_next_word; 304 bsdtar->optarg = opt_word; 305 } 306 } 307 } 308 309 /* We're reading a long option, including -W long=arg convention. */ 310 if (state == state_long) { 311 /* After this long option, we'll be starting a new word. */ 312 state = state_next_word; 313 314 /* Option name ends at '=' if there is one. */ 315 p = strchr(opt_word, '='); 316 if (p != NULL) { 317 optlength = (size_t)(p - opt_word); 318 bsdtar->optarg = (char *)(uintptr_t)(p + 1); 319 } else { 320 optlength = strlen(opt_word); 321 } 322 323 /* Search the table for an unambiguous match. */ 324 for (popt = tar_longopts; popt->name != NULL; popt++) { 325 /* Short-circuit if first chars don't match. */ 326 if (popt->name[0] != opt_word[0]) 327 continue; 328 /* If option is a prefix of name in table, record it.*/ 329 if (strncmp(opt_word, popt->name, optlength) == 0) { 330 match2 = match; /* Record up to two matches. */ 331 match = popt; 332 /* If it's an exact match, we're done. */ 333 if (strlen(popt->name) == optlength) { 334 match2 = NULL; /* Forget the others. */ 335 break; 336 } 337 } 338 } 339 340 /* Fail if there wasn't a unique match. */ 341 if (match == NULL) { 342 lafe_warnc(0, 343 "Option %s%s is not supported", 344 long_prefix, opt_word); 345 return ('?'); 346 } 347 if (match2 != NULL) { 348 lafe_warnc(0, 349 "Ambiguous option %s%s (matches --%s and --%s)", 350 long_prefix, opt_word, match->name, match2->name); 351 return ('?'); 352 } 353 354 /* We've found a unique match; does it need an argument? */ 355 if (match->required) { 356 /* Argument required: get next word if necessary. */ 357 if (bsdtar->optarg == NULL) { 358 bsdtar->optarg = *bsdtar->argv; 359 if (bsdtar->optarg == NULL) { 360 lafe_warnc(0, 361 "Option %s%s requires an argument", 362 long_prefix, match->name); 363 return ('?'); 364 } 365 ++bsdtar->argv; 366 --bsdtar->argc; 367 } 368 } else { 369 /* Argument forbidden: fail if there is one. */ 370 if (bsdtar->optarg != NULL) { 371 lafe_warnc(0, 372 "Option %s%s does not allow an argument", 373 long_prefix, match->name); 374 return ('?'); 375 } 376 } 377 return (match->equivalent); 378 } 379 380 return (opt); 381 } 382