xref: /dragonfly/bin/pax/pax.c (revision 984263bc)
1 /*-
2  * Copyright (c) 1992 Keith Muller.
3  * Copyright (c) 1992, 1993
4  *	The Regents of the University of California.  All rights reserved.
5  *
6  * This code is derived from software contributed to Berkeley by
7  * Keith Muller of the University of California, San Diego.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. All advertising materials mentioning features or use of this software
18  *    must display the following acknowledgement:
19  *	This product includes software developed by the University of
20  *	California, Berkeley and its contributors.
21  * 4. Neither the name of the University nor the names of its contributors
22  *    may be used to endorse or promote products derived from this software
23  *    without specific prior written permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35  * SUCH DAMAGE.
36  */
37 
38 #ifndef lint
39 static char const copyright[] =
40 "@(#) Copyright (c) 1992, 1993\n\
41 	The Regents of the University of California.  All rights reserved.\n";
42 #endif /* not lint */
43 
44 #ifndef lint
45 #if 0
46 static char sccsid[] = "@(#)pax.c	8.2 (Berkeley) 4/18/94";
47 #endif
48 static const char rcsid[] =
49   "$FreeBSD: src/bin/pax/pax.c,v 1.13.2.4 2002/11/07 15:29:53 imp Exp $";
50 #endif /* not lint */
51 
52 #include <sys/types.h>
53 #include <sys/stat.h>
54 #include <sys/time.h>
55 #include <sys/resource.h>
56 #include <err.h>
57 #include <errno.h>
58 #include <fcntl.h>
59 #include <locale.h>
60 #include <paths.h>
61 #include <signal.h>
62 #include <stdio.h>
63 #include <stdlib.h>
64 #include <string.h>
65 #include <unistd.h>
66 #include "pax.h"
67 #include "extern.h"
68 static int gen_init __P((void));
69 
70 /*
71  * PAX main routines, general globals and some simple start up routines
72  */
73 
74 /*
75  * Variables that can be accessed by any routine within pax
76  */
77 int	act = DEFOP;		/* read/write/append/copy */
78 FSUB	*frmt = NULL;		/* archive format type */
79 int	cflag;			/* match all EXCEPT pattern/file */
80 int	cwdfd;			/* starting cwd */
81 int	dflag;			/* directory member match only  */
82 int	iflag;			/* interactive file/archive rename */
83 int	kflag;			/* do not overwrite existing files */
84 int	lflag;			/* use hard links when possible */
85 int	nflag;			/* select first archive member match */
86 int	tflag;			/* restore access time after read */
87 int	uflag;			/* ignore older modification time files */
88 int	vflag;			/* produce verbose output */
89 int	Dflag;			/* same as uflag except inode change time */
90 int	Hflag;			/* follow command line symlinks (write only) */
91 int	Lflag;			/* follow symlinks when writing */
92 int	Xflag;			/* archive files with same device id only */
93 int	Yflag;			/* same as Dflg except after name mode */
94 int	Zflag;			/* same as uflg except after name mode */
95 int	vfpart;			/* is partial verbose output in progress */
96 int	patime = 1;		/* preserve file access time */
97 int	pmtime = 1;		/* preserve file modification times */
98 int	nodirs;			/* do not create directories as needed */
99 int	pmode;			/* preserve file mode bits */
100 int	pids;			/* preserve file uid/gid */
101 int	rmleadslash = 0;	/* remove leading '/' from pathnames */
102 int	exit_val;		/* exit value */
103 int	docrc;			/* check/create file crc */
104 char	*dirptr;		/* destination dir in a copy */
105 char	*argv0;			/* root of argv[0] */
106 sigset_t s_mask;		/* signal mask for cleanup critical sect */
107 FILE	*listf;			/* file pointer to print file list to */
108 char	*tempfile;		/* tempfile to use for mkstemp(3) */
109 char	*tempbase;		/* basename of tempfile to use for mkstemp(3) */
110 
111 /*
112  *	PAX - Portable Archive Interchange
113  *
114  * 	A utility to read, write, and write lists of the members of archive
115  *	files and copy directory hierarchies. A variety of archive formats
116  *	are supported (some are described in POSIX 1003.1 10.1):
117  *
118  *		ustar - 10.1.1 extended tar interchange format
119  *		cpio  - 10.1.2 extended cpio interchange format
120  *		tar - old BSD 4.3 tar format
121  *		binary cpio - old cpio with binary header format
122  *		sysVR4 cpio -  with and without CRC
123  *
124  * This version is a superset of IEEE Std 1003.2b-d3
125  *
126  * Summary of Extensions to the IEEE Standard:
127  *
128  * 1	READ ENHANCEMENTS
129  * 1.1	Operations which read archives will continue to operate even when
130  *	processing archives which may be damaged, truncated, or fail to meet
131  *	format specs in several different ways. Damaged sections of archives
132  *	are detected and avoided if possible. Attempts will be made to resync
133  *	archive read operations even with badly damaged media.
134  * 1.2	Blocksize requirements are not strictly enforced on archive read.
135  *	Tapes which have variable sized records can be read without errors.
136  * 1.3	The user can specify via the non-standard option flag -E if error
137  *	resync operation should stop on a media error, try a specified number
138  *	of times to correct, or try to correct forever.
139  * 1.4	Sparse files (lseek holes) stored on the archive (but stored with blocks
140  *	of all zeros will be restored with holes appropriate for the target
141  *	filesystem
142  * 1.5	The user is notified whenever something is found during archive
143  *	read operations which violates spec (but the read will continue).
144  * 1.6	Multiple archive volumes can be read and may span over different
145  *	archive devices
146  * 1.7	Rigidly restores all file attributes exactly as they are stored on the
147  *	archive.
148  * 1.8	Modification change time ranges can be specified via multiple -T
149  *	options. These allow a user to select files whose modification time
150  *	lies within a specific time range.
151  * 1.9	Files can be selected based on owner (user name or uid) via one or more
152  *	-U options.
153  * 1.10	Files can be selected based on group (group name or gid) via one o
154  *	more -G options.
155  * 1.11	File modification time can be checked against existing file after
156  *	name modification (-Z)
157  *
158  * 2	WRITE ENHANCEMENTS
159  * 2.1	Write operation will stop instead of allowing a user to create a flawed
160  *	flawed archive (due to any problem).
161  * 2.2	Archives written by pax are forced to strictly conform to both the
162  *	archive and pax the specific format specifications.
163  * 2.3	Blocking size and format is rigidly enforced on writes.
164  * 2.4	Formats which may exhibit header overflow problems (they have fields
165  *	too small for large file systems, such as inode number storage), use
166  *	routines designed to repair this problem. These techniques still
167  *	conform to both pax and format specifications, but no longer truncate
168  *	these fields. This removes any restrictions on using these archive
169  *	formats on large file systems.
170  * 2.5	Multiple archive volumes can be written and may span over different
171  *	archive devices
172  * 2.6	A archive volume record limit allows the user to specify the number
173  *	of bytes stored on an archive volume. When reached the user is
174  *	prompted for the next archive volume. This is specified with the
175  *	non-standard -B flag. The limit is rounded up to the next blocksize.
176  * 2.7	All archive padding during write use zero filled sections. This makes
177  *	it much easier to pull data out of flawed archive during read
178  *	operations.
179  * 2.8	Access time reset with the -t applies to all file nodes (including
180  *	directories).
181  * 2.9	Symbolic links can be followed with -L (optional in the spec).
182  * 2.10	Modification or inode change time ranges can be specified via
183  *	multiple -T options. These allow a user to select files whose
184  *	modification or inode change time lies within a specific time range.
185  * 2.11	Files can be selected based on owner (user name or uid) via one or more
186  *	-U options.
187  * 2.12	Files can be selected based on group (group name or gid) via one o
188  *	more -G options.
189  * 2.13	Symlinks which appear on the command line can be followed (without
190  *	following other symlinks; -H flag)
191  *
192  * 3	COPY ENHANCEMENTS
193  * 3.1	Sparse files (lseek holes) can be copied without expanding the holes
194  *	into zero filled blocks. The file copy is created with holes which are
195  *	appropriate for the target filesystem
196  * 3.2	Access time as well as modification time on copied file trees can be
197  *	preserved with the appropriate -p options.
198  * 3.3	Access time reset with the -t applies to all file nodes (including
199  *	directories).
200  * 3.4	Symbolic links can be followed with -L (optional in the spec).
201  * 3.5	Modification or inode change time ranges can be specified via
202  *	multiple -T options. These allow a user to select files whose
203  *	modification or inode change time lies within a specific time range.
204  * 3.6	Files can be selected based on owner (user name or uid) via one or more
205  *	-U options.
206  * 3.7	Files can be selected based on group (group name or gid) via one o
207  *	more -G options.
208  * 3.8	Symlinks which appear on the command line can be followed (without
209  *	following other symlinks; -H flag)
210  * 3.9  File inode change time can be checked against existing file before
211  *	name modification (-D)
212  * 3.10 File inode change time can be checked against existing file after
213  *	name modification (-Y)
214  * 3.11	File modification time can be checked against existing file after
215  *	name modification (-Z)
216  *
217  * 4	GENERAL ENHANCEMENTS
218  * 4.1	Internal structure is designed to isolate format dependent and
219  *	independent functions. Formats are selected via a format driver table.
220  *	This encourages the addition of new archive formats by only having to
221  *	write those routines which id, read and write the archive header.
222  */
223 
224 /*
225  * main()
226  *	parse options, set up and operate as specified by the user.
227  *	any operational flaw will set exit_val to non-zero
228  * Return: 0 if ok, 1 otherwise
229  */
230 
231 #ifdef __STDC__
232 int
233 main(int argc, char **argv)
234 #else
235 int
236 main(argc, argv)
237 	int argc;
238 	char **argv;
239 #endif
240 {
241 	char *tmpdir;
242 	size_t tdlen;
243 
244 	(void) setlocale(LC_ALL, "");
245 	listf = stderr;
246 	/*
247 	 * Keep a reference to cwd, so we can always come back home.
248 	 */
249 	cwdfd = open(".", O_RDONLY);
250 	if (cwdfd < 0) {
251 		syswarn(0, errno, "Can't open current working directory.");
252 		return(exit_val);
253 	}
254 
255 	/*
256 	 * Where should we put temporary files?
257 	 */
258 	if ((tmpdir = getenv("TMPDIR")) == NULL || *tmpdir == '\0')
259 		tmpdir = _PATH_TMP;
260 	tdlen = strlen(tmpdir);
261 	while(tdlen > 0 && tmpdir[tdlen - 1] == '/')
262 		tdlen--;
263 	tempfile = malloc(tdlen + 1 + sizeof(_TFILE_BASE));
264 	if (tempfile == NULL) {
265 		paxwarn(1, "Cannot allocate memory for temp file name.");
266 		return(exit_val);
267 	}
268 	if (tdlen)
269 		memcpy(tempfile, tmpdir, tdlen);
270 	tempbase = tempfile + tdlen;
271 	*tempbase++ = '/';
272 
273 	/*
274 	 * parse options, determine operational mode, general init
275 	 */
276 	options(argc, argv);
277 	if ((gen_init() < 0) || (tty_init() < 0))
278 		return(exit_val);
279 
280 	/*
281 	 * select a primary operation mode
282 	 */
283 	switch(act) {
284 	case EXTRACT:
285 		extract();
286 		break;
287 	case ARCHIVE:
288 		archive();
289 		break;
290 	case APPND:
291 		if (gzip_program != NULL)
292 			err(1, "can not gzip while appending");
293 		append();
294 		break;
295 	case COPY:
296 		copy();
297 		break;
298 	default:
299 	case LIST:
300 		list();
301 		break;
302 	}
303 	return(exit_val);
304 }
305 
306 /*
307  * sig_cleanup()
308  *	when interrupted we try to do whatever delayed processing we can.
309  *	This is not critical, but we really ought to limit our damage when we
310  *	are aborted by the user.
311  * Return:
312  *	never....
313  */
314 
315 #ifdef __STDC__
316 void
317 sig_cleanup(int which_sig)
318 #else
319 void
320 sig_cleanup(which_sig)
321 	int which_sig;
322 #endif
323 {
324 	/*
325 	 * restore modes and times for any dirs we may have created
326 	 * or any dirs we may have read. Set vflag and vfpart so the user
327 	 * will clearly see the message on a line by itself.
328 	 */
329 	vflag = vfpart = 1;
330 	if (which_sig == SIGXCPU)
331 		paxwarn(0, "Cpu time limit reached, cleaning up.");
332 	else
333 		paxwarn(0, "Signal caught, cleaning up.");
334 
335 	ar_close();
336 	proc_dir();
337 	if (tflag)
338 		atdir_end();
339 	exit(1);
340 }
341 
342 /*
343  * gen_init()
344  *	general setup routines. Not all are required, but they really help
345  *	when dealing with a medium to large sized archives.
346  */
347 
348 #ifdef __STDC__
349 static int
350 gen_init(void)
351 #else
352 static int
353 gen_init()
354 #endif
355 {
356 	struct rlimit reslimit;
357 	struct sigaction n_hand;
358 	struct sigaction o_hand;
359 
360 	/*
361 	 * Really needed to handle large archives. We can run out of memory for
362 	 * internal tables really fast when we have a whole lot of files...
363 	 */
364 	if (getrlimit(RLIMIT_DATA , &reslimit) == 0){
365 		reslimit.rlim_cur = reslimit.rlim_max;
366 		(void)setrlimit(RLIMIT_DATA , &reslimit);
367 	}
368 
369 	/*
370 	 * should file size limits be waived? if the os limits us, this is
371 	 * needed if we want to write a large archive
372 	 */
373 	if (getrlimit(RLIMIT_FSIZE , &reslimit) == 0){
374 		reslimit.rlim_cur = reslimit.rlim_max;
375 		(void)setrlimit(RLIMIT_FSIZE , &reslimit);
376 	}
377 
378 	/*
379 	 * increase the size the stack can grow to
380 	 */
381 	if (getrlimit(RLIMIT_STACK , &reslimit) == 0){
382 		reslimit.rlim_cur = reslimit.rlim_max;
383 		(void)setrlimit(RLIMIT_STACK , &reslimit);
384 	}
385 
386 	/*
387 	 * not really needed, but doesn't hurt
388 	 */
389 	if (getrlimit(RLIMIT_RSS , &reslimit) == 0){
390 		reslimit.rlim_cur = reslimit.rlim_max;
391 		(void)setrlimit(RLIMIT_RSS , &reslimit);
392 	}
393 
394 	/*
395 	 * signal handling to reset stored directory times and modes. Since
396 	 * we deal with broken pipes via failed writes we ignore it. We also
397 	 * deal with any file size limit thorugh failed writes. Cpu time
398 	 * limits are caught and a cleanup is forced.
399 	 */
400 	if ((sigemptyset(&s_mask) < 0) || (sigaddset(&s_mask, SIGTERM) < 0) ||
401 	    (sigaddset(&s_mask,SIGINT) < 0)||(sigaddset(&s_mask,SIGHUP) < 0) ||
402 	    (sigaddset(&s_mask,SIGPIPE) < 0)||(sigaddset(&s_mask,SIGQUIT)<0) ||
403 	    (sigaddset(&s_mask,SIGXCPU) < 0)||(sigaddset(&s_mask,SIGXFSZ)<0)) {
404 		paxwarn(1, "Unable to set up signal mask");
405 		return(-1);
406 	}
407 	memset(&n_hand, 0, sizeof n_hand);
408 	n_hand.sa_mask = s_mask;
409 	n_hand.sa_flags = 0;
410 	n_hand.sa_handler = sig_cleanup;
411 
412 	if ((sigaction(SIGHUP, &n_hand, &o_hand) < 0) &&
413 	    (o_hand.sa_handler == SIG_IGN) &&
414 	    (sigaction(SIGHUP, &o_hand, &o_hand) < 0))
415 		goto out;
416 
417 	if ((sigaction(SIGTERM, &n_hand, &o_hand) < 0) &&
418 	    (o_hand.sa_handler == SIG_IGN) &&
419 	    (sigaction(SIGTERM, &o_hand, &o_hand) < 0))
420 		goto out;
421 
422 	if ((sigaction(SIGINT, &n_hand, &o_hand) < 0) &&
423 	    (o_hand.sa_handler == SIG_IGN) &&
424 	    (sigaction(SIGINT, &o_hand, &o_hand) < 0))
425 		goto out;
426 
427 	if ((sigaction(SIGQUIT, &n_hand, &o_hand) < 0) &&
428 	    (o_hand.sa_handler == SIG_IGN) &&
429 	    (sigaction(SIGQUIT, &o_hand, &o_hand) < 0))
430 		goto out;
431 
432 	if ((sigaction(SIGXCPU, &n_hand, &o_hand) < 0) &&
433 	    (o_hand.sa_handler == SIG_IGN) &&
434 	    (sigaction(SIGXCPU, &o_hand, &o_hand) < 0))
435 		goto out;
436 
437 	n_hand.sa_handler = SIG_IGN;
438 	if ((sigaction(SIGPIPE, &n_hand, &o_hand) < 0) ||
439 	    (sigaction(SIGXFSZ, &n_hand, &o_hand) < 0))
440 		goto out;
441 	return(0);
442 
443     out:
444 	syswarn(1, errno, "Unable to set up signal handler");
445 	return(-1);
446 }
447