xref: /freebsd/contrib/libarchive/tar/bsdtar.c (revision 3e65b9c6e6b7b2081d54e1dc40983c3c00eaf738)
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 #include "bsdtar_platform.h"
27 __FBSDID("$FreeBSD$");
28 
29 #ifdef HAVE_SYS_PARAM_H
30 #include <sys/param.h>
31 #endif
32 #ifdef HAVE_SYS_STAT_H
33 #include <sys/stat.h>
34 #endif
35 #ifdef HAVE_ERRNO_H
36 #include <errno.h>
37 #endif
38 #ifdef HAVE_FCNTL_H
39 #include <fcntl.h>
40 #endif
41 #ifdef HAVE_LANGINFO_H
42 #include <langinfo.h>
43 #endif
44 #ifdef HAVE_LOCALE_H
45 #include <locale.h>
46 #endif
47 #ifdef HAVE_PATHS_H
48 #include <paths.h>
49 #endif
50 #ifdef HAVE_SIGNAL_H
51 #include <signal.h>
52 #endif
53 #include <stdio.h>
54 #ifdef HAVE_STDLIB_H
55 #include <stdlib.h>
56 #endif
57 #ifdef HAVE_STRING_H
58 #include <string.h>
59 #endif
60 #ifdef HAVE_TIME_H
61 #include <time.h>
62 #endif
63 #ifdef HAVE_UNISTD_H
64 #include <unistd.h>
65 #endif
66 #if HAVE_ZLIB_H
67 #include <zlib.h>
68 #endif
69 
70 #include "bsdtar.h"
71 #include "err.h"
72 
73 /*
74  * Per POSIX.1-1988, tar defaults to reading/writing archives to/from
75  * the default tape device for the system.  Pick something reasonable here.
76  */
77 #ifdef __linux
78 #define	_PATH_DEFTAPE "/dev/st0"
79 #endif
80 #if defined(_WIN32) && !defined(__CYGWIN__)
81 #define	_PATH_DEFTAPE "\\\\.\\tape0"
82 #endif
83 
84 #ifndef _PATH_DEFTAPE
85 #define	_PATH_DEFTAPE "/dev/tape"
86 #endif
87 
88 #ifdef __MINGW32__
89 int _CRT_glob = 0; /* Disable broken CRT globbing. */
90 #endif
91 
92 static struct bsdtar *_bsdtar;
93 
94 #if defined(HAVE_SIGACTION) && (defined(SIGINFO) || defined(SIGUSR1))
95 static volatile int siginfo_occurred;
96 
97 static void
98 siginfo_handler(int sig)
99 {
100 	(void)sig; /* UNUSED */
101 	siginfo_occurred = 1;
102 }
103 
104 int
105 need_report(void)
106 {
107 	int r = siginfo_occurred;
108 	siginfo_occurred = 0;
109 	return (r);
110 }
111 #else
112 int
113 need_report(void)
114 {
115 	return (0);
116 }
117 #endif
118 
119 /* External function to parse a date/time string */
120 time_t get_date(time_t, const char *);
121 
122 static void		 long_help(void);
123 static void		 only_mode(struct bsdtar *, const char *opt,
124 			     const char *valid);
125 static void		 set_mode(struct bsdtar *, char opt);
126 static void		 version(void);
127 
128 /* A basic set of security flags to request from libarchive. */
129 #define	SECURITY					\
130 	(ARCHIVE_EXTRACT_SECURE_SYMLINKS		\
131 	 | ARCHIVE_EXTRACT_SECURE_NODOTDOT)
132 
133 int
134 main(int argc, char **argv)
135 {
136 	struct bsdtar		*bsdtar, bsdtar_storage;
137 	int			 opt, t;
138 	char			 option_o;
139 	char			 possible_help_request;
140 	char			 buff[16];
141 	time_t			 now;
142 
143 	/*
144 	 * Use a pointer for consistency, but stack-allocated storage
145 	 * for ease of cleanup.
146 	 */
147 	_bsdtar = bsdtar = &bsdtar_storage;
148 	memset(bsdtar, 0, sizeof(*bsdtar));
149 	bsdtar->fd = -1; /* Mark as "unused" */
150 	bsdtar->gid = -1;
151 	bsdtar->uid = -1;
152 	option_o = 0;
153 
154 #if defined(HAVE_SIGACTION) && (defined(SIGINFO) || defined(SIGUSR1))
155 	{ /* Catch SIGINFO and SIGUSR1, if they exist. */
156 		struct sigaction sa;
157 		sa.sa_handler = siginfo_handler;
158 		sigemptyset(&sa.sa_mask);
159 		sa.sa_flags = 0;
160 #ifdef SIGINFO
161 		if (sigaction(SIGINFO, &sa, NULL))
162 			lafe_errc(1, errno, "sigaction(SIGINFO) failed");
163 #endif
164 #ifdef SIGUSR1
165 		/* ... and treat SIGUSR1 the same way as SIGINFO. */
166 		if (sigaction(SIGUSR1, &sa, NULL))
167 			lafe_errc(1, errno, "sigaction(SIGUSR1) failed");
168 #endif
169 	}
170 #endif
171 
172 
173 	/* Need lafe_progname before calling lafe_warnc. */
174 	if (*argv == NULL)
175 		lafe_progname = "bsdtar";
176 	else {
177 #if defined(_WIN32) && !defined(__CYGWIN__)
178 		lafe_progname = strrchr(*argv, '\\');
179 #else
180 		lafe_progname = strrchr(*argv, '/');
181 #endif
182 		if (lafe_progname != NULL)
183 			lafe_progname++;
184 		else
185 			lafe_progname = *argv;
186 	}
187 
188 	time(&now);
189 
190 #if HAVE_SETLOCALE
191 	if (setlocale(LC_ALL, "") == NULL)
192 		lafe_warnc(0, "Failed to set default locale");
193 #endif
194 #if defined(HAVE_NL_LANGINFO) && defined(HAVE_D_MD_ORDER)
195 	bsdtar->day_first = (*nl_langinfo(D_MD_ORDER) == 'd');
196 #endif
197 	possible_help_request = 0;
198 
199 	/* Look up uid of current user for future reference */
200 	bsdtar->user_uid = geteuid();
201 
202 	/* Default: open tape drive. */
203 	bsdtar->filename = getenv("TAPE");
204 	if (bsdtar->filename == NULL)
205 		bsdtar->filename = _PATH_DEFTAPE;
206 
207 	/* Default: preserve mod time on extract */
208 	bsdtar->extract_flags = ARCHIVE_EXTRACT_TIME;
209 
210 	/* Default: Perform basic security checks. */
211 	bsdtar->extract_flags |= SECURITY;
212 
213 #ifndef _WIN32
214 	/* On POSIX systems, assume --same-owner and -p when run by
215 	 * the root user.  This doesn't make any sense on Windows. */
216 	if (bsdtar->user_uid == 0) {
217 		/* --same-owner */
218 		bsdtar->extract_flags |= ARCHIVE_EXTRACT_OWNER;
219 		/* -p */
220 		bsdtar->extract_flags |= ARCHIVE_EXTRACT_PERM;
221 		bsdtar->extract_flags |= ARCHIVE_EXTRACT_ACL;
222 		bsdtar->extract_flags |= ARCHIVE_EXTRACT_XATTR;
223 		bsdtar->extract_flags |= ARCHIVE_EXTRACT_FFLAGS;
224 	}
225 #endif
226 
227 	bsdtar->argv = argv;
228 	bsdtar->argc = argc;
229 
230 	/*
231 	 * Comments following each option indicate where that option
232 	 * originated:  SUSv2, POSIX, GNU tar, star, etc.  If there's
233 	 * no such comment, then I don't know of anyone else who
234 	 * implements that option.
235 	 */
236 	while ((opt = bsdtar_getopt(bsdtar)) != -1) {
237 		switch (opt) {
238 		case 'B': /* GNU tar */
239 			/* libarchive doesn't need this; just ignore it. */
240 			break;
241 		case 'b': /* SUSv2 */
242 			t = atoi(bsdtar->optarg);
243 			if (t <= 0 || t > 8192)
244 				lafe_errc(1, 0,
245 				    "Argument to -b is out of range (1..8192)");
246 			bsdtar->bytes_per_block = 512 * t;
247 			break;
248 		case 'C': /* GNU tar */
249 			set_chdir(bsdtar, bsdtar->optarg);
250 			break;
251 		case 'c': /* SUSv2 */
252 			set_mode(bsdtar, opt);
253 			break;
254 		case OPTION_CHECK_LINKS: /* GNU tar */
255 			bsdtar->option_warn_links = 1;
256 			break;
257 		case OPTION_CHROOT: /* NetBSD */
258 			bsdtar->option_chroot = 1;
259 			break;
260 		case OPTION_EXCLUDE: /* GNU tar */
261 			if (lafe_exclude(&bsdtar->matching, bsdtar->optarg))
262 				lafe_errc(1, 0,
263 				    "Couldn't exclude %s\n", bsdtar->optarg);
264 			break;
265 		case OPTION_FORMAT: /* GNU tar, others */
266 			bsdtar->create_format = bsdtar->optarg;
267 			break;
268 		case 'f': /* SUSv2 */
269 			bsdtar->filename = bsdtar->optarg;
270 			if (strcmp(bsdtar->filename, "-") == 0)
271 				bsdtar->filename = NULL;
272 			break;
273 		case OPTION_GID: /* cpio */
274 			t = atoi(bsdtar->optarg);
275 			if (t < 0)
276 				lafe_errc(1, 0,
277 				    "Argument to --gid must be positive");
278 			bsdtar->gid = t;
279 			break;
280 		case OPTION_GNAME: /* cpio */
281 			bsdtar->gname = bsdtar->optarg;
282 			break;
283 		case 'H': /* BSD convention */
284 			bsdtar->symlink_mode = 'H';
285 			break;
286 		case 'h': /* Linux Standards Base, gtar; synonym for -L */
287 			bsdtar->symlink_mode = 'L';
288 			/* Hack: -h by itself is the "help" command. */
289 			possible_help_request = 1;
290 			break;
291 		case OPTION_HELP: /* GNU tar, others */
292 			long_help();
293 			exit(0);
294 			break;
295 		case 'I': /* GNU tar */
296 			/*
297 			 * TODO: Allow 'names' to come from an archive,
298 			 * not just a text file.  Design a good UI for
299 			 * allowing names and mode/owner to be read
300 			 * from an archive, with contents coming from
301 			 * disk.  This can be used to "refresh" an
302 			 * archive or to design archives with special
303 			 * permissions without having to create those
304 			 * permissions on disk.
305 			 */
306 			bsdtar->names_from_file = bsdtar->optarg;
307 			break;
308 		case OPTION_INCLUDE:
309 			/*
310 			 * Noone else has the @archive extension, so
311 			 * noone else needs this to filter entries
312 			 * when transforming archives.
313 			 */
314 			if (lafe_include(&bsdtar->matching, bsdtar->optarg))
315 				lafe_errc(1, 0,
316 				    "Failed to add %s to inclusion list",
317 				    bsdtar->optarg);
318 			break;
319 		case 'j': /* GNU tar */
320 			if (bsdtar->create_compression != '\0')
321 				lafe_errc(1, 0,
322 				    "Can't specify both -%c and -%c", opt,
323 				    bsdtar->create_compression);
324 			bsdtar->create_compression = opt;
325 			break;
326 		case 'J': /* GNU tar 1.21 and later */
327 			if (bsdtar->create_compression != '\0')
328 				lafe_errc(1, 0,
329 				    "Can't specify both -%c and -%c", opt,
330 				    bsdtar->create_compression);
331 			bsdtar->create_compression = opt;
332 			break;
333 		case 'k': /* GNU tar */
334 			bsdtar->extract_flags |= ARCHIVE_EXTRACT_NO_OVERWRITE;
335 			break;
336 		case OPTION_KEEP_NEWER_FILES: /* GNU tar */
337 			bsdtar->extract_flags |= ARCHIVE_EXTRACT_NO_OVERWRITE_NEWER;
338 			break;
339 		case 'L': /* BSD convention */
340 			bsdtar->symlink_mode = 'L';
341 			break;
342 	        case 'l': /* SUSv2 and GNU tar beginning with 1.16 */
343 			/* GNU tar 1.13  used -l for --one-file-system */
344 			bsdtar->option_warn_links = 1;
345 			break;
346 		case OPTION_LZMA:
347 			if (bsdtar->create_compression != '\0')
348 				lafe_errc(1, 0,
349 				    "Can't specify both -%c and -%c", opt,
350 				    bsdtar->create_compression);
351 			bsdtar->create_compression = opt;
352 			break;
353 		case 'm': /* SUSv2 */
354 			bsdtar->extract_flags &= ~ARCHIVE_EXTRACT_TIME;
355 			break;
356 		case 'n': /* GNU tar */
357 			bsdtar->option_no_subdirs = 1;
358 			break;
359 	        /*
360 		 * Selecting files by time:
361 		 *    --newer-?time='date' Only files newer than 'date'
362 		 *    --newer-?time-than='file' Only files newer than time
363 		 *         on specified file (useful for incremental backups)
364 		 * TODO: Add corresponding "older" options to reverse these.
365 		 */
366 		case OPTION_NEWER_CTIME: /* GNU tar */
367 			bsdtar->newer_ctime_sec = get_date(now, bsdtar->optarg);
368 			break;
369 		case OPTION_NEWER_CTIME_THAN:
370 			{
371 				struct stat st;
372 				if (stat(bsdtar->optarg, &st) != 0)
373 					lafe_errc(1, 0,
374 					    "Can't open file %s", bsdtar->optarg);
375 				bsdtar->newer_ctime_sec = st.st_ctime;
376 				bsdtar->newer_ctime_nsec =
377 				    ARCHIVE_STAT_CTIME_NANOS(&st);
378 			}
379 			break;
380 		case OPTION_NEWER_MTIME: /* GNU tar */
381 			bsdtar->newer_mtime_sec = get_date(now, bsdtar->optarg);
382 			break;
383 		case OPTION_NEWER_MTIME_THAN:
384 			{
385 				struct stat st;
386 				if (stat(bsdtar->optarg, &st) != 0)
387 					lafe_errc(1, 0,
388 					    "Can't open file %s", bsdtar->optarg);
389 				bsdtar->newer_mtime_sec = st.st_mtime;
390 				bsdtar->newer_mtime_nsec =
391 				    ARCHIVE_STAT_MTIME_NANOS(&st);
392 			}
393 			break;
394 		case OPTION_NODUMP: /* star */
395 			bsdtar->option_honor_nodump = 1;
396 			break;
397 		case OPTION_NO_SAME_OWNER: /* GNU tar */
398 			bsdtar->extract_flags &= ~ARCHIVE_EXTRACT_OWNER;
399 			break;
400 		case OPTION_NO_SAME_PERMISSIONS: /* GNU tar */
401 			bsdtar->extract_flags &= ~ARCHIVE_EXTRACT_PERM;
402 			bsdtar->extract_flags &= ~ARCHIVE_EXTRACT_ACL;
403 			bsdtar->extract_flags &= ~ARCHIVE_EXTRACT_XATTR;
404 			bsdtar->extract_flags &= ~ARCHIVE_EXTRACT_FFLAGS;
405 			break;
406 		case OPTION_NULL: /* GNU tar */
407 			bsdtar->option_null++;
408 			break;
409 		case OPTION_NUMERIC_OWNER: /* GNU tar */
410 			bsdtar->uname = "";
411 			bsdtar->gname = "";
412 			break;
413 		case 'O': /* GNU tar */
414 			bsdtar->option_stdout = 1;
415 			break;
416 		case 'o': /* SUSv2 and GNU conflict here, but not fatally */
417 			option_o = 1; /* Record it and resolve it later. */
418 			break;
419 		case OPTION_ONE_FILE_SYSTEM: /* GNU tar */
420 			bsdtar->option_dont_traverse_mounts = 1;
421 			break;
422 		case OPTION_OPTIONS:
423 			bsdtar->option_options = bsdtar->optarg;
424 			break;
425 #if 0
426 		/*
427 		 * The common BSD -P option is not necessary, since
428 		 * our default is to archive symlinks, not follow
429 		 * them.  This is convenient, as -P conflicts with GNU
430 		 * tar anyway.
431 		 */
432 		case 'P': /* BSD convention */
433 			/* Default behavior, no option necessary. */
434 			break;
435 #endif
436 		case 'P': /* GNU tar */
437 			bsdtar->extract_flags &= ~SECURITY;
438 			bsdtar->option_absolute_paths = 1;
439 			break;
440 		case 'p': /* GNU tar, star */
441 			bsdtar->extract_flags |= ARCHIVE_EXTRACT_PERM;
442 			bsdtar->extract_flags |= ARCHIVE_EXTRACT_ACL;
443 			bsdtar->extract_flags |= ARCHIVE_EXTRACT_XATTR;
444 			bsdtar->extract_flags |= ARCHIVE_EXTRACT_FFLAGS;
445 			break;
446 		case OPTION_POSIX: /* GNU tar */
447 			bsdtar->create_format = "pax";
448 			break;
449 		case 'q': /* FreeBSD GNU tar --fast-read, NetBSD -q */
450 			bsdtar->option_fast_read = 1;
451 			break;
452 		case 'r': /* SUSv2 */
453 			set_mode(bsdtar, opt);
454 			break;
455 		case 'S': /* NetBSD pax-as-tar */
456 			bsdtar->extract_flags |= ARCHIVE_EXTRACT_SPARSE;
457 			break;
458 		case 's': /* NetBSD pax-as-tar */
459 #if HAVE_REGEX_H
460 			add_substitution(bsdtar, bsdtar->optarg);
461 #else
462 			lafe_warnc(0,
463 			    "-s is not supported by this version of bsdtar");
464 			usage();
465 #endif
466 			break;
467 		case OPTION_SAME_OWNER: /* GNU tar */
468 			bsdtar->extract_flags |= ARCHIVE_EXTRACT_OWNER;
469 			break;
470 		case OPTION_STRIP_COMPONENTS: /* GNU tar 1.15 */
471 			bsdtar->strip_components = atoi(bsdtar->optarg);
472 			break;
473 		case 'T': /* GNU tar */
474 			bsdtar->names_from_file = bsdtar->optarg;
475 			break;
476 		case 't': /* SUSv2 */
477 			set_mode(bsdtar, opt);
478 			bsdtar->verbose++;
479 			break;
480 		case OPTION_TOTALS: /* GNU tar */
481 			bsdtar->option_totals++;
482 			break;
483 		case 'U': /* GNU tar */
484 			bsdtar->extract_flags |= ARCHIVE_EXTRACT_UNLINK;
485 			bsdtar->option_unlink_first = 1;
486 			break;
487 		case 'u': /* SUSv2 */
488 			set_mode(bsdtar, opt);
489 			break;
490 		case OPTION_UID: /* cpio */
491 			t = atoi(bsdtar->optarg);
492 			if (t < 0)
493 				lafe_errc(1, 0,
494 				    "Argument to --uid must be positive");
495 			bsdtar->uid = t;
496 			break;
497 		case OPTION_UNAME: /* cpio */
498 			bsdtar->uname = bsdtar->optarg;
499 			break;
500 		case 'v': /* SUSv2 */
501 			bsdtar->verbose++;
502 			break;
503 		case OPTION_VERSION: /* GNU convention */
504 			version();
505 			break;
506 #if 0
507 		/*
508 		 * The -W longopt feature is handled inside of
509 		 * bsdtar_getopt(), so -W is not available here.
510 		 */
511 		case 'W': /* Obscure GNU convention. */
512 			break;
513 #endif
514 		case 'w': /* SUSv2 */
515 			bsdtar->option_interactive = 1;
516 			break;
517 		case 'X': /* GNU tar */
518 			if (lafe_exclude_from_file(&bsdtar->matching, bsdtar->optarg))
519 				lafe_errc(1, 0,
520 				    "failed to process exclusions from file %s",
521 				    bsdtar->optarg);
522 			break;
523 		case 'x': /* SUSv2 */
524 			set_mode(bsdtar, opt);
525 			break;
526 		case 'y': /* FreeBSD version of GNU tar */
527 			if (bsdtar->create_compression != '\0')
528 				lafe_errc(1, 0,
529 				    "Can't specify both -%c and -%c", opt,
530 				    bsdtar->create_compression);
531 			bsdtar->create_compression = opt;
532 			break;
533 		case 'Z': /* GNU tar */
534 			if (bsdtar->create_compression != '\0')
535 				lafe_errc(1, 0,
536 				    "Can't specify both -%c and -%c", opt,
537 				    bsdtar->create_compression);
538 			bsdtar->create_compression = opt;
539 			break;
540 		case 'z': /* GNU tar, star, many others */
541 			if (bsdtar->create_compression != '\0')
542 				lafe_errc(1, 0,
543 				    "Can't specify both -%c and -%c", opt,
544 				    bsdtar->create_compression);
545 			bsdtar->create_compression = opt;
546 			break;
547 		case OPTION_USE_COMPRESS_PROGRAM:
548 			bsdtar->compress_program = bsdtar->optarg;
549 			break;
550 		default:
551 			usage();
552 		}
553 	}
554 
555 	/*
556 	 * Sanity-check options.
557 	 */
558 
559 	/* If no "real" mode was specified, treat -h as --help. */
560 	if ((bsdtar->mode == '\0') && possible_help_request) {
561 		long_help();
562 		exit(0);
563 	}
564 
565 	/* Otherwise, a mode is required. */
566 	if (bsdtar->mode == '\0')
567 		lafe_errc(1, 0,
568 		    "Must specify one of -c, -r, -t, -u, -x");
569 
570 	/* Check boolean options only permitted in certain modes. */
571 	if (bsdtar->option_dont_traverse_mounts)
572 		only_mode(bsdtar, "--one-file-system", "cru");
573 	if (bsdtar->option_fast_read)
574 		only_mode(bsdtar, "--fast-read", "xt");
575 	if (bsdtar->option_honor_nodump)
576 		only_mode(bsdtar, "--nodump", "cru");
577 	if (option_o > 0) {
578 		switch (bsdtar->mode) {
579 		case 'c':
580 			/*
581 			 * In GNU tar, -o means "old format."  The
582 			 * "ustar" format is the closest thing
583 			 * supported by libarchive.
584 			 */
585 			bsdtar->create_format = "ustar";
586 			/* TODO: bsdtar->create_format = "v7"; */
587 			break;
588 		case 'x':
589 			/* POSIX-compatible behavior. */
590 			bsdtar->option_no_owner = 1;
591 			bsdtar->extract_flags &= ~ARCHIVE_EXTRACT_OWNER;
592 			break;
593 		default:
594 			only_mode(bsdtar, "-o", "xc");
595 			break;
596 		}
597 	}
598 	if (bsdtar->option_no_subdirs)
599 		only_mode(bsdtar, "-n", "cru");
600 	if (bsdtar->option_stdout)
601 		only_mode(bsdtar, "-O", "xt");
602 	if (bsdtar->option_unlink_first)
603 		only_mode(bsdtar, "-U", "x");
604 	if (bsdtar->option_warn_links)
605 		only_mode(bsdtar, "--check-links", "cr");
606 
607 	/* Check other parameters only permitted in certain modes. */
608 	if (bsdtar->create_compression != '\0') {
609 		strcpy(buff, "-?");
610 		buff[1] = bsdtar->create_compression;
611 		only_mode(bsdtar, buff, "cxt");
612 	}
613 	if (bsdtar->create_format != NULL)
614 		only_mode(bsdtar, "--format", "cru");
615 	if (bsdtar->symlink_mode != '\0') {
616 		strcpy(buff, "-?");
617 		buff[1] = bsdtar->symlink_mode;
618 		only_mode(bsdtar, buff, "cru");
619 	}
620 	if (bsdtar->strip_components != 0)
621 		only_mode(bsdtar, "--strip-components", "xt");
622 
623 	switch(bsdtar->mode) {
624 	case 'c':
625 		tar_mode_c(bsdtar);
626 		break;
627 	case 'r':
628 		tar_mode_r(bsdtar);
629 		break;
630 	case 't':
631 		tar_mode_t(bsdtar);
632 		break;
633 	case 'u':
634 		tar_mode_u(bsdtar);
635 		break;
636 	case 'x':
637 		tar_mode_x(bsdtar);
638 		break;
639 	}
640 
641 	lafe_cleanup_exclusions(&bsdtar->matching);
642 #if HAVE_REGEX_H
643 	cleanup_substitution(bsdtar);
644 #endif
645 
646 	if (bsdtar->return_value != 0)
647 		lafe_warnc(0,
648 		    "Error exit delayed from previous errors.");
649 	return (bsdtar->return_value);
650 }
651 
652 static void
653 set_mode(struct bsdtar *bsdtar, char opt)
654 {
655 	if (bsdtar->mode != '\0' && bsdtar->mode != opt)
656 		lafe_errc(1, 0,
657 		    "Can't specify both -%c and -%c", opt, bsdtar->mode);
658 	bsdtar->mode = opt;
659 }
660 
661 /*
662  * Verify that the mode is correct.
663  */
664 static void
665 only_mode(struct bsdtar *bsdtar, const char *opt, const char *valid_modes)
666 {
667 	if (strchr(valid_modes, bsdtar->mode) == NULL)
668 		lafe_errc(1, 0,
669 		    "Option %s is not permitted in mode -%c",
670 		    opt, bsdtar->mode);
671 }
672 
673 
674 void
675 usage(void)
676 {
677 	const char	*p;
678 
679 	p = lafe_progname;
680 
681 	fprintf(stderr, "Usage:\n");
682 	fprintf(stderr, "  List:    %s -tf <archive-filename>\n", p);
683 	fprintf(stderr, "  Extract: %s -xf <archive-filename>\n", p);
684 	fprintf(stderr, "  Create:  %s -cf <archive-filename> [filenames...]\n", p);
685 	fprintf(stderr, "  Help:    %s --help\n", p);
686 	exit(1);
687 }
688 
689 static void
690 version(void)
691 {
692 	printf("bsdtar %s - %s\n",
693 	    BSDTAR_VERSION_STRING,
694 	    archive_version());
695 	exit(0);
696 }
697 
698 static const char *long_help_msg =
699 	"First option must be a mode specifier:\n"
700 	"  -c Create  -r Add/Replace  -t List  -u Update  -x Extract\n"
701 	"Common Options:\n"
702 	"  -b #  Use # 512-byte records per I/O block\n"
703 	"  -f <filename>  Location of archive (default " _PATH_DEFTAPE ")\n"
704 	"  -v    Verbose\n"
705 	"  -w    Interactive\n"
706 	"Create: %p -c [options] [<file> | <dir> | @<archive> | -C <dir> ]\n"
707 	"  <file>, <dir>  add these items to archive\n"
708 	"  -z, -j, -J, --lzma  Compress archive with gzip/bzip2/xz/lzma\n"
709 	"  --format {ustar|pax|cpio|shar}  Select archive format\n"
710 	"  --exclude <pattern>  Skip files that match pattern\n"
711 	"  -C <dir>  Change to <dir> before processing remaining files\n"
712 	"  @<archive>  Add entries from <archive> to output\n"
713 	"List: %p -t [options] [<patterns>]\n"
714 	"  <patterns>  If specified, list only entries that match\n"
715 	"Extract: %p -x [options] [<patterns>]\n"
716 	"  <patterns>  If specified, extract only entries that match\n"
717 	"  -k    Keep (don't overwrite) existing files\n"
718 	"  -m    Don't restore modification times\n"
719 	"  -O    Write entries to stdout, don't restore to disk\n"
720 	"  -p    Restore permissions (including ACLs, owner, file flags)\n";
721 
722 
723 /*
724  * Note that the word 'bsdtar' will always appear in the first line
725  * of output.
726  *
727  * In particular, /bin/sh scripts that need to test for the presence
728  * of bsdtar can use the following template:
729  *
730  * if (tar --help 2>&1 | grep bsdtar >/dev/null 2>&1 ) then \
731  *          echo bsdtar; else echo not bsdtar; fi
732  */
733 static void
734 long_help(void)
735 {
736 	const char	*prog;
737 	const char	*p;
738 
739 	prog = lafe_progname;
740 
741 	fflush(stderr);
742 
743 	p = (strcmp(prog,"bsdtar") != 0) ? "(bsdtar)" : "";
744 	printf("%s%s: manipulate archive files\n", prog, p);
745 
746 	for (p = long_help_msg; *p != '\0'; p++) {
747 		if (*p == '%') {
748 			if (p[1] == 'p') {
749 				fputs(prog, stdout);
750 				p++;
751 			} else
752 				putchar('%');
753 		} else
754 			putchar(*p);
755 	}
756 	version();
757 }
758