external/bsd/libarchive/dist/tar/cmdline.c

   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 }