xref: /dragonfly/bin/pax/pax.c (revision c03f08f3)
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  * @(#) Copyright (c) 1992, 1993 The Regents of the University of California.  All rights reserved.
38  * @(#)pax.c	8.2 (Berkeley) 4/18/94
39  * $FreeBSD: src/bin/pax/pax.c,v 1.13.2.4 2002/11/07 15:29:53 imp Exp $
40  * $DragonFly: src/bin/pax/pax.c,v 1.6 2006/09/27 21:58:08 pavalos Exp $
41  */
42 
43 #include <sys/types.h>
44 #include <sys/stat.h>
45 #include <sys/time.h>
46 #include <sys/resource.h>
47 #include <err.h>
48 #include <errno.h>
49 #include <fcntl.h>
50 #include <locale.h>
51 #include <paths.h>
52 #include <signal.h>
53 #include <stdio.h>
54 #include <stdlib.h>
55 #include <string.h>
56 #include <unistd.h>
57 #include "pax.h"
58 #include "extern.h"
59 static int gen_init (void);
60 
61 /*
62  * PAX main routines, general globals and some simple start up routines
63  */
64 
65 /*
66  * Variables that can be accessed by any routine within pax
67  */
68 int	act = DEFOP;		/* read/write/append/copy */
69 FSUB	*frmt = NULL;		/* archive format type */
70 int	cflag;			/* match all EXCEPT pattern/file */
71 int	cwdfd;			/* starting cwd */
72 int	dflag;			/* directory member match only  */
73 int	iflag;			/* interactive file/archive rename */
74 int	kflag;			/* do not overwrite existing files */
75 int	lflag;			/* use hard links when possible */
76 int	nflag;			/* select first archive member match */
77 int	tflag;			/* restore access time after read */
78 int	uflag;			/* ignore older modification time files */
79 int	vflag;			/* produce verbose output */
80 int	Dflag;			/* same as uflag except inode change time */
81 int	Hflag;			/* follow command line symlinks (write only) */
82 int	Lflag;			/* follow symlinks when writing */
83 int	Xflag;			/* archive files with same device id only */
84 int	Yflag;			/* same as Dflag except after name mode */
85 int	Zflag;			/* same as uflag except after name mode */
86 int	vfpart;			/* is partial verbose output in progress */
87 int	patime = 1;		/* preserve file access time */
88 int	pmtime = 1;		/* preserve file modification times */
89 int	nodirs;			/* do not create directories as needed */
90 int	pmode;			/* preserve file mode bits */
91 int	pids;			/* preserve file uid/gid */
92 int	rmleadslash = 0;	/* remove leading '/' from pathnames */
93 int	exit_val;		/* exit value */
94 int	docrc;			/* check/create file crc */
95 char	*dirptr;		/* destination dir in a copy */
96 char	*argv0;			/* root of argv[0] */
97 sigset_t s_mask;		/* signal mask for cleanup critical sect */
98 FILE	*listf;			/* file pointer to print file list to */
99 char	*tempfile;		/* tempfile to use for mkstemp(3) */
100 char	*tempbase;		/* basename of tempfile to use for mkstemp(3) */
101 
102 /*
103  *	PAX - Portable Archive Interchange
104  *
105  * 	A utility to read, write, and write lists of the members of archive
106  *	files and copy directory hierarchies. A variety of archive formats
107  *	are supported (some are described in POSIX 1003.1 10.1):
108  *
109  *		ustar - 10.1.1 extended tar interchange format
110  *		cpio  - 10.1.2 extended cpio interchange format
111  *		tar - old BSD 4.3 tar format
112  *		binary cpio - old cpio with binary header format
113  *		sysVR4 cpio -  with and without CRC
114  *
115  * This version is a superset of IEEE Std 1003.2b-d3
116  *
117  * Summary of Extensions to the IEEE Standard:
118  *
119  * 1	READ ENHANCEMENTS
120  * 1.1	Operations which read archives will continue to operate even when
121  *	processing archives which may be damaged, truncated, or fail to meet
122  *	format specs in several different ways. Damaged sections of archives
123  *	are detected and avoided if possible. Attempts will be made to resync
124  *	archive read operations even with badly damaged media.
125  * 1.2	Blocksize requirements are not strictly enforced on archive read.
126  *	Tapes which have variable sized records can be read without errors.
127  * 1.3	The user can specify via the non-standard option flag -E if error
128  *	resync operation should stop on a media error, try a specified number
129  *	of times to correct, or try to correct forever.
130  * 1.4	Sparse files (lseek holes) stored on the archive (but stored with blocks
131  *	of all zeros will be restored with holes appropriate for the target
132  *	filesystem
133  * 1.5	The user is notified whenever something is found during archive
134  *	read operations which violates spec (but the read will continue).
135  * 1.6	Multiple archive volumes can be read and may span over different
136  *	archive devices
137  * 1.7	Rigidly restores all file attributes exactly as they are stored on the
138  *	archive.
139  * 1.8	Modification change time ranges can be specified via multiple -T
140  *	options. These allow a user to select files whose modification time
141  *	lies within a specific time range.
142  * 1.9	Files can be selected based on owner (user name or uid) via one or more
143  *	-U options.
144  * 1.10	Files can be selected based on group (group name or gid) via one o
145  *	more -G options.
146  * 1.11	File modification time can be checked against existing file after
147  *	name modification (-Z)
148  *
149  * 2	WRITE ENHANCEMENTS
150  * 2.1	Write operation will stop instead of allowing a user to create a flawed
151  *	flawed archive (due to any problem).
152  * 2.2	Archives written by pax are forced to strictly conform to both the
153  *	archive and pax the specific format specifications.
154  * 2.3	Blocking size and format is rigidly enforced on writes.
155  * 2.4	Formats which may exhibit header overflow problems (they have fields
156  *	too small for large file systems, such as inode number storage), use
157  *	routines designed to repair this problem. These techniques still
158  *	conform to both pax and format specifications, but no longer truncate
159  *	these fields. This removes any restrictions on using these archive
160  *	formats on large file systems.
161  * 2.5	Multiple archive volumes can be written and may span over different
162  *	archive devices
163  * 2.6	A archive volume record limit allows the user to specify the number
164  *	of bytes stored on an archive volume. When reached the user is
165  *	prompted for the next archive volume. This is specified with the
166  *	non-standard -B flag. The limit is rounded up to the next blocksize.
167  * 2.7	All archive padding during write use zero filled sections. This makes
168  *	it much easier to pull data out of flawed archive during read
169  *	operations.
170  * 2.8	Access time reset with the -t applies to all file nodes (including
171  *	directories).
172  * 2.9	Symbolic links can be followed with -L (optional in the spec).
173  * 2.10	Modification or inode change time ranges can be specified via
174  *	multiple -T options. These allow a user to select files whose
175  *	modification or inode change time lies within a specific time range.
176  * 2.11	Files can be selected based on owner (user name or uid) via one or more
177  *	-U options.
178  * 2.12	Files can be selected based on group (group name or gid) via one o
179  *	more -G options.
180  * 2.13	Symlinks which appear on the command line can be followed (without
181  *	following other symlinks; -H flag)
182  *
183  * 3	COPY ENHANCEMENTS
184  * 3.1	Sparse files (lseek holes) can be copied without expanding the holes
185  *	into zero filled blocks. The file copy is created with holes which are
186  *	appropriate for the target filesystem
187  * 3.2	Access time as well as modification time on copied file trees can be
188  *	preserved with the appropriate -p options.
189  * 3.3	Access time reset with the -t applies to all file nodes (including
190  *	directories).
191  * 3.4	Symbolic links can be followed with -L (optional in the spec).
192  * 3.5	Modification or inode change time ranges can be specified via
193  *	multiple -T options. These allow a user to select files whose
194  *	modification or inode change time lies within a specific time range.
195  * 3.6	Files can be selected based on owner (user name or uid) via one or more
196  *	-U options.
197  * 3.7	Files can be selected based on group (group name or gid) via one o
198  *	more -G options.
199  * 3.8	Symlinks which appear on the command line can be followed (without
200  *	following other symlinks; -H flag)
201  * 3.9  File inode change time can be checked against existing file before
202  *	name modification (-D)
203  * 3.10 File inode change time can be checked against existing file after
204  *	name modification (-Y)
205  * 3.11	File modification time can be checked against existing file after
206  *	name modification (-Z)
207  *
208  * 4	GENERAL ENHANCEMENTS
209  * 4.1	Internal structure is designed to isolate format dependent and
210  *	independent functions. Formats are selected via a format driver table.
211  *	This encourages the addition of new archive formats by only having to
212  *	write those routines which id, read and write the archive header.
213  */
214 
215 /*
216  * main()
217  *	parse options, set up and operate as specified by the user.
218  *	any operational flaw will set exit_val to non-zero
219  * Return: 0 if ok, 1 otherwise
220  */
221 
222 int
223 main(int argc, char **argv)
224 {
225 	char *tmpdir;
226 	size_t tdlen;
227 
228 	setlocale(LC_ALL, "");
229 	listf = stderr;
230 	/*
231 	 * Keep a reference to cwd, so we can always come back home.
232 	 */
233 	cwdfd = open(".", O_RDONLY);
234 	if (cwdfd < 0) {
235 		syswarn(0, errno, "Can't open current working directory.");
236 		return(exit_val);
237 	}
238 
239 	/*
240 	 * Where should we put temporary files?
241 	 */
242 	if ((tmpdir = getenv("TMPDIR")) == NULL || *tmpdir == '\0')
243 		tmpdir = _PATH_TMP;
244 	tdlen = strlen(tmpdir);
245 	while(tdlen > 0 && tmpdir[tdlen - 1] == '/')
246 		tdlen--;
247 	tempfile = malloc(tdlen + 1 + sizeof(_TFILE_BASE));
248 	if (tempfile == NULL) {
249 		paxwarn(1, "Cannot allocate memory for temp file name.");
250 		return(exit_val);
251 	}
252 	if (tdlen)
253 		memcpy(tempfile, tmpdir, tdlen);
254 	tempbase = tempfile + tdlen;
255 	*tempbase++ = '/';
256 
257 	/*
258 	 * parse options, determine operational mode, general init
259 	 */
260 	options(argc, argv);
261 	if ((gen_init() < 0) || (tty_init() < 0))
262 		return(exit_val);
263 
264 	/*
265 	 * select a primary operation mode
266 	 */
267 	switch(act) {
268 	case EXTRACT:
269 		extract();
270 		break;
271 	case ARCHIVE:
272 		archive();
273 		break;
274 	case APPND:
275 		if (gzip_program != NULL)
276 			err(1, "can not gzip while appending");
277 		append();
278 		break;
279 	case COPY:
280 		copy();
281 		break;
282 	default:
283 	case LIST:
284 		list();
285 		break;
286 	}
287 	return(exit_val);
288 }
289 
290 /*
291  * sig_cleanup()
292  *	when interrupted we try to do whatever delayed processing we can.
293  *	This is not critical, but we really ought to limit our damage when we
294  *	are aborted by the user.
295  * Return:
296  *	never....
297  */
298 
299 void
300 sig_cleanup(int which_sig)
301 {
302 	/*
303 	 * restore modes and times for any dirs we may have created
304 	 * or any dirs we may have read. Set vflag and vfpart so the user
305 	 * will clearly see the message on a line by itself.
306 	 */
307 	vflag = vfpart = 1;
308 	if (which_sig == SIGXCPU)
309 		paxwarn(0, "Cpu time limit reached, cleaning up.");
310 	else
311 		paxwarn(0, "Signal caught, cleaning up.");
312 
313 	ar_close();
314 	proc_dir();
315 	if (tflag)
316 		atdir_end();
317 	exit(1);
318 }
319 
320 /*
321  * gen_init()
322  *	general setup routines. Not all are required, but they really help
323  *	when dealing with a medium to large sized archives.
324  */
325 
326 static int
327 gen_init(void)
328 {
329 	struct rlimit reslimit;
330 	struct sigaction n_hand;
331 	struct sigaction o_hand;
332 
333 	/*
334 	 * Really needed to handle large archives. We can run out of memory for
335 	 * internal tables really fast when we have a whole lot of files...
336 	 */
337 	if (getrlimit(RLIMIT_DATA , &reslimit) == 0){
338 		reslimit.rlim_cur = reslimit.rlim_max;
339 		setrlimit(RLIMIT_DATA , &reslimit);
340 	}
341 
342 	/*
343 	 * should file size limits be waived? if the os limits us, this is
344 	 * needed if we want to write a large archive
345 	 */
346 	if (getrlimit(RLIMIT_FSIZE , &reslimit) == 0){
347 		reslimit.rlim_cur = reslimit.rlim_max;
348 		setrlimit(RLIMIT_FSIZE , &reslimit);
349 	}
350 
351 	/*
352 	 * increase the size the stack can grow to
353 	 */
354 	if (getrlimit(RLIMIT_STACK , &reslimit) == 0){
355 		reslimit.rlim_cur = reslimit.rlim_max;
356 		setrlimit(RLIMIT_STACK , &reslimit);
357 	}
358 
359 	/*
360 	 * not really needed, but doesn't hurt
361 	 */
362 	if (getrlimit(RLIMIT_RSS , &reslimit) == 0){
363 		reslimit.rlim_cur = reslimit.rlim_max;
364 		setrlimit(RLIMIT_RSS , &reslimit);
365 	}
366 
367 	/*
368 	 * signal handling to reset stored directory times and modes. Since
369 	 * we deal with broken pipes via failed writes we ignore it. We also
370 	 * deal with any file size limit through failed writes. Cpu time
371 	 * limits are caught and a cleanup is forced.
372 	 */
373 	if ((sigemptyset(&s_mask) < 0) || (sigaddset(&s_mask, SIGTERM) < 0) ||
374 	    (sigaddset(&s_mask,SIGINT) < 0)||(sigaddset(&s_mask,SIGHUP) < 0) ||
375 	    (sigaddset(&s_mask,SIGPIPE) < 0)||(sigaddset(&s_mask,SIGQUIT)<0) ||
376 	    (sigaddset(&s_mask,SIGXCPU) < 0)||(sigaddset(&s_mask,SIGXFSZ)<0)) {
377 		paxwarn(1, "Unable to set up signal mask");
378 		return(-1);
379 	}
380 	memset(&n_hand, 0, sizeof n_hand);
381 	n_hand.sa_mask = s_mask;
382 	n_hand.sa_flags = 0;
383 	n_hand.sa_handler = sig_cleanup;
384 
385 	if ((sigaction(SIGHUP, &n_hand, &o_hand) < 0) &&
386 	    (o_hand.sa_handler == SIG_IGN) &&
387 	    (sigaction(SIGHUP, &o_hand, &o_hand) < 0))
388 		goto out;
389 
390 	if ((sigaction(SIGTERM, &n_hand, &o_hand) < 0) &&
391 	    (o_hand.sa_handler == SIG_IGN) &&
392 	    (sigaction(SIGTERM, &o_hand, &o_hand) < 0))
393 		goto out;
394 
395 	if ((sigaction(SIGINT, &n_hand, &o_hand) < 0) &&
396 	    (o_hand.sa_handler == SIG_IGN) &&
397 	    (sigaction(SIGINT, &o_hand, &o_hand) < 0))
398 		goto out;
399 
400 	if ((sigaction(SIGQUIT, &n_hand, &o_hand) < 0) &&
401 	    (o_hand.sa_handler == SIG_IGN) &&
402 	    (sigaction(SIGQUIT, &o_hand, &o_hand) < 0))
403 		goto out;
404 
405 	if ((sigaction(SIGXCPU, &n_hand, &o_hand) < 0) &&
406 	    (o_hand.sa_handler == SIG_IGN) &&
407 	    (sigaction(SIGXCPU, &o_hand, &o_hand) < 0))
408 		goto out;
409 
410 	n_hand.sa_handler = SIG_IGN;
411 	if ((sigaction(SIGPIPE, &n_hand, &o_hand) < 0) ||
412 	    (sigaction(SIGXFSZ, &n_hand, &o_hand) < 0))
413 		goto out;
414 	return(0);
415 
416     out:
417 	syswarn(1, errno, "Unable to set up signal handler");
418 	return(-1);
419 }
420