xref: /freebsd/bin/pax/pax.c (revision 5ebc7e6281887681c3a348a5a4c902e262ccd656)
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  *	$Id: pax.c,v 1.2 1994/09/24 02:56:27 davidg Exp $
38  */
39 
40 #ifndef lint
41 static char copyright[] =
42 "@(#) Copyright (c) 1992, 1993\n\
43 	The Regents of the University of California.  All rights reserved.\n";
44 #endif /* not lint */
45 
46 #ifndef lint
47 static char sccsid[] = "@(#)pax.c	8.2 (Berkeley) 4/18/94";
48 #endif /* not lint */
49 
50 #include <stdio.h>
51 #include <sys/types.h>
52 #include <sys/param.h>
53 #include <sys/stat.h>
54 #include <sys/time.h>
55 #include <sys/resource.h>
56 #include <signal.h>
57 #include <unistd.h>
58 #include <stdlib.h>
59 #include <errno.h>
60 #include "pax.h"
61 #include "extern.h"
62 static int gen_init __P((void));
63 
64 /*
65  * PAX main routines, general globals and some simple start up routines
66  */
67 
68 /*
69  * Variables that can be accessed by any routine within pax
70  */
71 int	act = DEFOP;		/* read/write/append/copy */
72 FSUB	*frmt = NULL;		/* archive format type */
73 int	cflag;			/* match all EXCEPT pattern/file */
74 int	dflag;			/* directory member match only  */
75 int	iflag;			/* interactive file/archive rename */
76 int	kflag;			/* do not overwrite existing files */
77 int	lflag;			/* use hard links when possible */
78 int	nflag;			/* select first archive member match */
79 int	tflag;			/* restore access time after read */
80 int	uflag;			/* ignore older modification time files */
81 int	vflag;			/* produce verbose output */
82 int	Dflag;			/* same as uflag except inode change time */
83 int	Hflag;			/* follow command line symlinks (write only) */
84 int	Lflag;			/* follow symlinks when writing */
85 int	Xflag;			/* archive files with same device id only */
86 int	Yflag;			/* same as Dflg except after name mode */
87 int	Zflag;			/* same as uflg except after name mode */
88 int	vfpart;			/* is partial verbose output in progress */
89 int	patime = 1;		/* preserve file access time */
90 int	pmtime = 1;		/* preserve file modification times */
91 int	pmode;			/* preserve file mode bits */
92 int	pids;			/* preserve file uid/gid */
93 int	exit_val;		/* exit value */
94 int	docrc;			/* check/create file crc */
95 char	*dirptr;		/* destination dir in a copy */
96 char	*ltmfrmt;		/* -v locale time format (if any) */
97 char	*argv0;			/* root of argv[0] */
98 sigset_t s_mask;		/* signal mask for cleanup critical sect */
99 
100 /*
101  *	PAX - Portable Archive Interchange
102  *
103  * 	A utility to read, write, and write lists of the members of archive
104  *	files and copy directory hierarchies. A variety of archive formats
105  *	are supported (some are described in POSIX 1003.1 10.1):
106  *
107  *		ustar - 10.1.1 extended tar interchange format
108  *		cpio  - 10.1.2 extended cpio interchange format
109  *		tar - old BSD 4.3 tar format
110  *		binary cpio - old cpio with binary header format
111  *		sysVR4 cpio -  with and without CRC
112  *
113  * This version is a superset of IEEE Std 1003.2b-d3
114  *
115  * Summary of Extensions to the IEEE Standard:
116  *
117  * 1	READ ENHANCEMENTS
118  * 1.1	Operations which read archives will continue to operate even when
119  *	processing archives which may be damaged, truncated, or fail to meet
120  *	format specs in several different ways. Damaged sections of archives
121  *	are detected and avoided if possible. Attempts will be made to resync
122  *	archive read operations even with badly damaged media.
123  * 1.2	Blocksize requirements are not strictly enforced on archive read.
124  *	Tapes which have variable sized records can be read without errors.
125  * 1.3	The user can specify via the non-standard option flag -E if error
126  *	resync operation should stop on a media error, try a specified number
127  *	of times to correct, or try to correct forever.
128  * 1.4	Sparse files (lseek holes) stored on the archive (but stored with blocks
129  *	of all zeros will be restored with holes appropriate for the target
130  *	filesystem
131  * 1.5	The user is notified whenever something is found during archive
132  *	read operations which violates spec (but the read will continue).
133  * 1.6	Multiple archive volumes can be read and may span over different
134  *	archive devices
135  * 1.7	Rigidly restores all file attributes exactly as they are stored on the
136  *	archive.
137  * 1.8	Modification change time ranges can be specified via multiple -T
138  *	options. These allow a user to select files whose modification time
139  *	lies within a specific time range.
140  * 1.9	Files can be selected based on owner (user name or uid) via one or more
141  *	-U options.
142  * 1.10	Files can be selected based on group (group name or gid) via one o
143  *	more -G options.
144  * 1.11	File modification time can be checked against exisiting file after
145  *	name modification (-Z)
146  *
147  * 2	WRITE ENHANCEMENTS
148  * 2.1	Write operation will stop instead of allowing a user to create a flawed
149  *	flawed archive (due to any problem).
150  * 2.2	Archives writtens by pax are forced to strictly conform to both the
151  *	archive and pax the spceific format specifications.
152  * 2.3	Blocking size and format is rigidly enforced on writes.
153  * 2.4	Formats which may exhibit header overflow problems (they have fields
154  *	too small for large file systems, such as inode number storage), use
155  *	routines designed to repair this problem. These techniques still
156  *	conform to both pax and format specifications, but no longer truncate
157  *	these fields. This removes any restrictions on using these archive
158  *	formats on large file systems.
159  * 2.5	Multiple archive volumes can be written and may span over different
160  *	archive devices
161  * 2.6	A archive volume record limit allows the user to specify the number
162  *	of bytes stored on an archive volume. When reached the user is
163  *	prompted for the next archive volume. This is specified with the
164  *	non-standard -B flag. THe limit is rounded up to the next blocksize.
165  * 2.7	All archive padding during write use zero filled sections. This makes
166  *	it much easier to pull data out of flawed archive during read
167  *	operations.
168  * 2.8	Access time reset with the -t applies to all file nodes (including
169  *	directories).
170  * 2.9	Symbolic links can be followed with -L (optional in the spec).
171  * 2.10	Modification or inode change time ranges can be specified via
172  *	multiple -T options. These allow a user to select files whose
173  *	modification or inode change time lies within a specific time range.
174  * 2.11	Files can be selected based on owner (user name or uid) via one or more
175  *	-U options.
176  * 2.12	Files can be selected based on group (group name or gid) via one o
177  *	more -G options.
178  * 2.13	Symlinks which appear on the command line can be followed (without
179  *	following other symlinks; -H flag)
180  *
181  * 3	COPY ENHANCEMENTS
182  * 3.1	Sparse files (lseek holes) can be copied without expanding the holes
183  *	into zero filled blocks. The file copy is created with holes which are
184  *	appropriate for the target filesystem
185  * 3.2	Access time as well as modification time on copied file trees can be
186  *	preserved with the appropriate -p options.
187  * 3.3	Access time reset with the -t applies to all file nodes (including
188  *	directories).
189  * 3.4	Symbolic links can be followed with -L (optional in the spec).
190  * 3.5	Modification or inode change time ranges can be specified via
191  *	multiple -T options. These allow a user to select files whose
192  *	modification or inode change time lies within a specific time range.
193  * 3.6	Files can be selected based on owner (user name or uid) via one or more
194  *	-U options.
195  * 3.7	Files can be selected based on group (group name or gid) via one o
196  *	more -G options.
197  * 3.8	Symlinks which appear on the command line can be followed (without
198  *	following other symlinks; -H flag)
199  * 3.9  File inode change time can be checked against exisiting file before
200  *	name modification (-D)
201  * 3.10 File inode change time can be checked against exisiting file after
202  *	name modification (-Y)
203  * 3.11	File modification time can be checked against exisiting file after
204  *	name modification (-Z)
205  *
206  * 4	GENERAL ENHANCEMENTS
207  * 4.1	Internal structure is designed to isolate format dependent and
208  *	independent functions. Formats are selected via a format driver table.
209  *	This encourages the addition of new archive formats by only having to
210  *	write those routines which id, read and write the archive header.
211  */
212 
213 /*
214  * main()
215  *	parse options, set up and operate as specified by the user.
216  *	any operational flaw will set exit_val to non-zero
217  * Return: 0 if ok, 1 otherwise
218  */
219 
220 #if __STDC__
221 int
222 main(int argc, char **argv)
223 #else
224 int
225 main(argc, argv)
226 	int argc;
227 	char **argv;
228 #endif
229 {
230 	/*
231 	 * parse options, determine operational mode, general init
232 	 */
233 	options(argc, argv);
234         if ((gen_init() < 0) || (tty_init() < 0))
235 		return(exit_val);
236 
237 	/*
238 	 * select a primary operation mode
239 	 */
240 	switch(act) {
241 	case EXTRACT:
242 		extract();
243 		break;
244 	case ARCHIVE:
245 		archive();
246 		break;
247 	case APPND:
248 		append();
249 		break;
250 	case COPY:
251 		copy();
252 		break;
253 	default:
254 	case LIST:
255 		list();
256 		break;
257 	}
258 	return(exit_val);
259 }
260 
261 /*
262  * sig_cleanup()
263  *	when interrupted we try to do whatever delayed processing we can.
264  *	This is not critical, but we really ought to limit our damage when we
265  *	are aborted by the user.
266  * Return:
267  *	never....
268  */
269 
270 #if __STDC__
271 void
272 sig_cleanup(int which_sig)
273 #else
274 void
275 sig_cleanup(which_sig)
276 	int which_sig;
277 #endif
278 {
279 	/*
280 	 * restore modes and times for any dirs we may have created
281 	 * or any dirs we may have read. Set vflag and vfpart so the user
282 	 * will clearly see the message on a line by itself.
283 	 */
284 	vflag = vfpart = 1;
285 	if (which_sig == SIGXCPU)
286 		warn(0, "Cpu time limit reached, cleaning up.");
287 	else
288 		warn(0, "Signal caught, cleaning up.");
289 
290 	ar_close();
291 	proc_dir();
292 	if (tflag)
293 		atdir_end();
294 	exit(1);
295 }
296 
297 /*
298  * gen_init()
299  *	general setup routines. Not all are required, but they really help
300  *	when dealing with a medium to large sized archives.
301  */
302 
303 #if __STDC__
304 static int
305 gen_init(void)
306 #else
307 static int
308 gen_init()
309 #endif
310 {
311 	struct rlimit reslimit;
312 	struct sigaction n_hand;
313 	struct sigaction o_hand;
314 
315 	/*
316 	 * Really needed to handle large archives. We can run out of memory for
317 	 * internal tables really fast when we have a whole lot of files...
318 	 */
319 	if (getrlimit(RLIMIT_DATA , &reslimit) == 0){
320 		reslimit.rlim_cur = reslimit.rlim_max;
321 		(void)setrlimit(RLIMIT_DATA , &reslimit);
322 	}
323 
324 	/*
325 	 * should file size limits be waived? if the os limits us, this is
326 	 * needed if we want to write a large archive
327 	 */
328 	if (getrlimit(RLIMIT_FSIZE , &reslimit) == 0){
329 		reslimit.rlim_cur = reslimit.rlim_max;
330 		(void)setrlimit(RLIMIT_FSIZE , &reslimit);
331 	}
332 
333 	/*
334 	 * increase the size the stack can grow to
335 	 */
336 	if (getrlimit(RLIMIT_STACK , &reslimit) == 0){
337 		reslimit.rlim_cur = reslimit.rlim_max;
338 		(void)setrlimit(RLIMIT_STACK , &reslimit);
339 	}
340 
341 	/*
342 	 * not really needed, but doesn't hurt
343 	 */
344 	if (getrlimit(RLIMIT_RSS , &reslimit) == 0){
345 		reslimit.rlim_cur = reslimit.rlim_max;
346 		(void)setrlimit(RLIMIT_RSS , &reslimit);
347 	}
348 
349 	/*
350 	 * Handle posix locale
351 	 *
352 	 * set user defines time printing format for -v option
353 	 */
354 	ltmfrmt = getenv("LC_TIME");
355 
356 	/*
357 	 * signal handling to reset stored directory times and modes. Since
358 	 * we deal with broken pipes via failed writes we ignore it. We also
359 	 * deal with any file size limit thorugh failed writes. Cpu time
360 	 * limits are caught and a cleanup is forced.
361 	 */
362 	if ((sigemptyset(&s_mask) < 0) || (sigaddset(&s_mask, SIGTERM) < 0) ||
363 	    (sigaddset(&s_mask,SIGINT) < 0)||(sigaddset(&s_mask,SIGHUP) < 0) ||
364 	    (sigaddset(&s_mask,SIGPIPE) < 0)||(sigaddset(&s_mask,SIGQUIT)<0) ||
365 	    (sigaddset(&s_mask,SIGXCPU) < 0)||(sigaddset(&s_mask,SIGXFSZ)<0)) {
366 		warn(1, "Unable to set up signal mask");
367 		return(-1);
368 	}
369 	n_hand.sa_mask = s_mask;
370 	n_hand.sa_flags = 0;
371 	n_hand.sa_handler = sig_cleanup;
372 
373 	if ((sigaction(SIGHUP, &n_hand, &o_hand) < 0) &&
374 	    (o_hand.sa_handler == SIG_IGN) &&
375 	    (sigaction(SIGHUP, &o_hand, &o_hand) < 0))
376 		goto out;
377 
378 	if ((sigaction(SIGTERM, &n_hand, &o_hand) < 0) &&
379 	    (o_hand.sa_handler == SIG_IGN) &&
380 	    (sigaction(SIGTERM, &o_hand, &o_hand) < 0))
381 		goto out;
382 
383 	if ((sigaction(SIGINT, &n_hand, &o_hand) < 0) &&
384 	    (o_hand.sa_handler == SIG_IGN) &&
385 	    (sigaction(SIGINT, &o_hand, &o_hand) < 0))
386 		goto out;
387 
388 	if ((sigaction(SIGQUIT, &n_hand, &o_hand) < 0) &&
389 	    (o_hand.sa_handler == SIG_IGN) &&
390 	    (sigaction(SIGQUIT, &o_hand, &o_hand) < 0))
391 		goto out;
392 
393 	if ((sigaction(SIGXCPU, &n_hand, &o_hand) < 0) &&
394 	    (o_hand.sa_handler == SIG_IGN) &&
395 	    (sigaction(SIGXCPU, &o_hand, &o_hand) < 0))
396 		goto out;
397 
398 	n_hand.sa_handler = SIG_IGN;
399 	if ((sigaction(SIGPIPE, &n_hand, &o_hand) < 0) ||
400 	    (sigaction(SIGXFSZ, &n_hand, &o_hand) < 0))
401 		goto out;
402 	return(0);
403 
404     out:
405 	syswarn(1, errno, "Unable to set up signal handler");
406 	return(-1);
407 }
408