xref: /original-bsd/bin/pax/pax.c (revision 612877e1)
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  * %sccs.include.redist.c%
10  */
11 
12 #ifndef lint
13 static char copyright[] =
14 "@(#) Copyright (c) 1992, 1993\n\
15 	The Regents of the University of California.  All rights reserved.\n";
16 #endif /* not lint */
17 
18 #ifndef lint
19 static char sccsid[] = "@(#)pax.c	8.2 (Berkeley) 04/18/94";
20 #endif /* not lint */
21 
22 #include <stdio.h>
23 #include <sys/types.h>
24 #include <sys/param.h>
25 #include <sys/stat.h>
26 #include <sys/time.h>
27 #include <sys/resource.h>
28 #include <signal.h>
29 #include <unistd.h>
30 #include <stdlib.h>
31 #include <errno.h>
32 #include "pax.h"
33 #include "extern.h"
34 static int gen_init __P((void));
35 
36 /*
37  * PAX main routines, general globals and some simple start up routines
38  */
39 
40 /*
41  * Variables that can be accessed by any routine within pax
42  */
43 int	act = DEFOP;		/* read/write/append/copy */
44 FSUB	*frmt = NULL;		/* archive format type */
45 int	cflag;			/* match all EXCEPT pattern/file */
46 int	dflag;			/* directory member match only  */
47 int	iflag;			/* interactive file/archive rename */
48 int	kflag;			/* do not overwrite existing files */
49 int	lflag;			/* use hard links when possible */
50 int	nflag;			/* select first archive member match */
51 int	tflag;			/* restore access time after read */
52 int	uflag;			/* ignore older modification time files */
53 int	vflag;			/* produce verbose output */
54 int	Dflag;			/* same as uflag except inode change time */
55 int	Hflag;			/* follow command line symlinks (write only) */
56 int	Lflag;			/* follow symlinks when writing */
57 int	Xflag;			/* archive files with same device id only */
58 int	Yflag;			/* same as Dflg except after name mode */
59 int	Zflag;			/* same as uflg except after name mode */
60 int	vfpart;			/* is partial verbose output in progress */
61 int	patime = 1;		/* preserve file access time */
62 int	pmtime = 1;		/* preserve file modification times */
63 int	pmode;			/* preserve file mode bits */
64 int	pids;			/* preserve file uid/gid */
65 int	exit_val;		/* exit value */
66 int	docrc;			/* check/create file crc */
67 char	*dirptr;		/* destination dir in a copy */
68 char	*ltmfrmt;		/* -v locale time format (if any) */
69 char	*argv0;			/* root of argv[0] */
70 sigset_t s_mask;		/* signal mask for cleanup critical sect */
71 
72 /*
73  *	PAX - Portable Archive Interchange
74  *
75  * 	A utility to read, write, and write lists of the members of archive
76  *	files and copy directory hierarchies. A variety of archive formats
77  *	are supported (some are described in POSIX 1003.1 10.1):
78  *
79  *		ustar - 10.1.1 extended tar interchange format
80  *		cpio  - 10.1.2 extended cpio interchange format
81  *		tar - old BSD 4.3 tar format
82  *		binary cpio - old cpio with binary header format
83  *		sysVR4 cpio -  with and without CRC
84  *
85  * This version is a superset of IEEE Std 1003.2b-d3
86  *
87  * Summary of Extensions to the IEEE Standard:
88  *
89  * 1	READ ENHANCEMENTS
90  * 1.1	Operations which read archives will continue to operate even when
91  *	processing archives which may be damaged, truncated, or fail to meet
92  *	format specs in several different ways. Damaged sections of archives
93  *	are detected and avoided if possible. Attempts will be made to resync
94  *	archive read operations even with badly damaged media.
95  * 1.2	Blocksize requirements are not strictly enforced on archive read.
96  *	Tapes which have variable sized records can be read without errors.
97  * 1.3	The user can specify via the non-standard option flag -E if error
98  *	resync operation should stop on a media error, try a specified number
99  *	of times to correct, or try to correct forever.
100  * 1.4	Sparse files (lseek holes) stored on the archive (but stored with blocks
101  *	of all zeros will be restored with holes appropriate for the target
102  *	filesystem
103  * 1.5	The user is notified whenever something is found during archive
104  *	read operations which violates spec (but the read will continue).
105  * 1.6	Multiple archive volumes can be read and may span over different
106  *	archive devices
107  * 1.7	Rigidly restores all file attributes exactly as they are stored on the
108  *	archive.
109  * 1.8	Modification change time ranges can be specified via multiple -T
110  *	options. These allow a user to select files whose modification time
111  *	lies within a specific time range.
112  * 1.9	Files can be selected based on owner (user name or uid) via one or more
113  *	-U options.
114  * 1.10	Files can be selected based on group (group name or gid) via one o
115  *	more -G options.
116  * 1.11	File modification time can be checked against exisiting file after
117  *	name modification (-Z)
118  *
119  * 2	WRITE ENHANCEMENTS
120  * 2.1	Write operation will stop instead of allowing a user to create a flawed
121  *	flawed archive (due to any problem).
122  * 2.2	Archives writtens by pax are forced to strictly conform to both the
123  *	archive and pax the spceific format specifications.
124  * 2.3	Blocking size and format is rigidly enforced on writes.
125  * 2.4	Formats which may exhibit header overflow problems (they have fields
126  *	too small for large file systems, such as inode number storage), use
127  *	routines designed to repair this problem. These techniques still
128  *	conform to both pax and format specifications, but no longer truncate
129  *	these fields. This removes any restrictions on using these archive
130  *	formats on large file systems.
131  * 2.5	Multiple archive volumes can be written and may span over different
132  *	archive devices
133  * 2.6	A archive volume record limit allows the user to specify the number
134  *	of bytes stored on an archive volume. When reached the user is
135  *	prompted for the next archive volume. This is specified with the
136  *	non-standard -B flag. THe limit is rounded up to the next blocksize.
137  * 2.7	All archive padding during write use zero filled sections. This makes
138  *	it much easier to pull data out of flawed archive during read
139  *	operations.
140  * 2.8	Access time reset with the -t applies to all file nodes (including
141  *	directories).
142  * 2.9	Symbolic links can be followed with -L (optional in the spec).
143  * 2.10	Modification or inode change time ranges can be specified via
144  *	multiple -T options. These allow a user to select files whose
145  *	modification or inode change time lies within a specific time range.
146  * 2.11	Files can be selected based on owner (user name or uid) via one or more
147  *	-U options.
148  * 2.12	Files can be selected based on group (group name or gid) via one o
149  *	more -G options.
150  * 2.13	Symlinks which appear on the command line can be followed (without
151  *	following other symlinks; -H flag)
152  *
153  * 3	COPY ENHANCEMENTS
154  * 3.1	Sparse files (lseek holes) can be copied without expanding the holes
155  *	into zero filled blocks. The file copy is created with holes which are
156  *	appropriate for the target filesystem
157  * 3.2	Access time as well as modification time on copied file trees can be
158  *	preserved with the appropriate -p options.
159  * 3.3	Access time reset with the -t applies to all file nodes (including
160  *	directories).
161  * 3.4	Symbolic links can be followed with -L (optional in the spec).
162  * 3.5	Modification or inode change time ranges can be specified via
163  *	multiple -T options. These allow a user to select files whose
164  *	modification or inode change time lies within a specific time range.
165  * 3.6	Files can be selected based on owner (user name or uid) via one or more
166  *	-U options.
167  * 3.7	Files can be selected based on group (group name or gid) via one o
168  *	more -G options.
169  * 3.8	Symlinks which appear on the command line can be followed (without
170  *	following other symlinks; -H flag)
171  * 3.9  File inode change time can be checked against exisiting file before
172  *	name modification (-D)
173  * 3.10 File inode change time can be checked against exisiting file after
174  *	name modification (-Y)
175  * 3.11	File modification time can be checked against exisiting file after
176  *	name modification (-Z)
177  *
178  * 4	GENERAL ENHANCEMENTS
179  * 4.1	Internal structure is designed to isolate format dependent and
180  *	independent functions. Formats are selected via a format driver table.
181  *	This encourages the addition of new archive formats by only having to
182  *	write those routines which id, read and write the archive header.
183  */
184 
185 /*
186  * main()
187  *	parse options, set up and operate as specified by the user.
188  *	any operational flaw will set exit_val to non-zero
189  * Return: 0 if ok, 1 otherwise
190  */
191 
192 #if __STDC__
193 int
194 main(int argc, char **argv)
195 #else
196 int
197 main(argc, argv)
198 	int argc;
199 	char **argv;
200 #endif
201 {
202 	/*
203 	 * parse options, determine operational mode, general init
204 	 */
205 	options(argc, argv);
206         if ((gen_init() < 0) || (tty_init() < 0))
207 		return(exit_val);
208 
209 	/*
210 	 * select a primary operation mode
211 	 */
212 	switch(act) {
213 	case EXTRACT:
214 		extract();
215 		break;
216 	case ARCHIVE:
217 		archive();
218 		break;
219 	case APPND:
220 		append();
221 		break;
222 	case COPY:
223 		copy();
224 		break;
225 	default:
226 	case LIST:
227 		list();
228 		break;
229 	}
230 	return(exit_val);
231 }
232 
233 /*
234  * sig_cleanup()
235  *	when interrupted we try to do whatever delayed processing we can.
236  *	This is not critical, but we really ought to limit our damage when we
237  *	are aborted by the user.
238  * Return:
239  *	never....
240  */
241 
242 #if __STDC__
243 void
244 sig_cleanup(int which_sig)
245 #else
246 void
247 sig_cleanup(which_sig)
248 	int which_sig;
249 #endif
250 {
251 	/*
252 	 * restore modes and times for any dirs we may have created
253 	 * or any dirs we may have read. Set vflag and vfpart so the user
254 	 * will clearly see the message on a line by itself.
255 	 */
256 	vflag = vfpart = 1;
257 	if (which_sig == SIGXCPU)
258 		warn(0, "Cpu time limit reached, cleaning up.");
259 	else
260 		warn(0, "Signal caught, cleaning up.");
261 
262 	ar_close();
263 	proc_dir();
264 	if (tflag)
265 		atdir_end();
266 	exit(1);
267 }
268 
269 /*
270  * gen_init()
271  *	general setup routines. Not all are required, but they really help
272  *	when dealing with a medium to large sized archives.
273  */
274 
275 #if __STDC__
276 static int
277 gen_init(void)
278 #else
279 static int
280 gen_init()
281 #endif
282 {
283 	struct rlimit reslimit;
284 	struct sigaction n_hand;
285 	struct sigaction o_hand;
286 
287 	/*
288 	 * Really needed to handle large archives. We can run out of memory for
289 	 * internal tables really fast when we have a whole lot of files...
290 	 */
291 	if (getrlimit(RLIMIT_DATA , &reslimit) == 0){
292 		reslimit.rlim_cur = reslimit.rlim_max;
293 		(void)setrlimit(RLIMIT_DATA , &reslimit);
294 	}
295 
296 	/*
297 	 * should file size limits be waived? if the os limits us, this is
298 	 * needed if we want to write a large archive
299 	 */
300 	if (getrlimit(RLIMIT_FSIZE , &reslimit) == 0){
301 		reslimit.rlim_cur = reslimit.rlim_max;
302 		(void)setrlimit(RLIMIT_FSIZE , &reslimit);
303 	}
304 
305 	/*
306 	 * increase the size the stack can grow to
307 	 */
308 	if (getrlimit(RLIMIT_STACK , &reslimit) == 0){
309 		reslimit.rlim_cur = reslimit.rlim_max;
310 		(void)setrlimit(RLIMIT_STACK , &reslimit);
311 	}
312 
313 	/*
314 	 * not really needed, but doesn't hurt
315 	 */
316 	if (getrlimit(RLIMIT_RSS , &reslimit) == 0){
317 		reslimit.rlim_cur = reslimit.rlim_max;
318 		(void)setrlimit(RLIMIT_RSS , &reslimit);
319 	}
320 
321 	/*
322 	 * Handle posix locale
323 	 *
324 	 * set user defines time printing format for -v option
325 	 */
326 	ltmfrmt = getenv("LC_TIME");
327 
328 	/*
329 	 * signal handling to reset stored directory times and modes. Since
330 	 * we deal with broken pipes via failed writes we ignore it. We also
331 	 * deal with any file size limit thorugh failed writes. Cpu time
332 	 * limits are caught and a cleanup is forced.
333 	 */
334 	if ((sigemptyset(&s_mask) < 0) || (sigaddset(&s_mask, SIGTERM) < 0) ||
335 	    (sigaddset(&s_mask,SIGINT) < 0)||(sigaddset(&s_mask,SIGHUP) < 0) ||
336 	    (sigaddset(&s_mask,SIGPIPE) < 0)||(sigaddset(&s_mask,SIGQUIT)<0) ||
337 	    (sigaddset(&s_mask,SIGXCPU) < 0)||(sigaddset(&s_mask,SIGXFSZ)<0)) {
338 		warn(1, "Unable to set up signal mask");
339 		return(-1);
340 	}
341 	n_hand.sa_mask = s_mask;
342 	n_hand.sa_flags = 0;
343 	n_hand.sa_handler = sig_cleanup;
344 
345 	if ((sigaction(SIGHUP, &n_hand, &o_hand) < 0) &&
346 	    (o_hand.sa_handler == SIG_IGN) &&
347 	    (sigaction(SIGHUP, &o_hand, &o_hand) < 0))
348 		goto out;
349 
350 	if ((sigaction(SIGTERM, &n_hand, &o_hand) < 0) &&
351 	    (o_hand.sa_handler == SIG_IGN) &&
352 	    (sigaction(SIGTERM, &o_hand, &o_hand) < 0))
353 		goto out;
354 
355 	if ((sigaction(SIGINT, &n_hand, &o_hand) < 0) &&
356 	    (o_hand.sa_handler == SIG_IGN) &&
357 	    (sigaction(SIGINT, &o_hand, &o_hand) < 0))
358 		goto out;
359 
360 	if ((sigaction(SIGQUIT, &n_hand, &o_hand) < 0) &&
361 	    (o_hand.sa_handler == SIG_IGN) &&
362 	    (sigaction(SIGQUIT, &o_hand, &o_hand) < 0))
363 		goto out;
364 
365 	if ((sigaction(SIGXCPU, &n_hand, &o_hand) < 0) &&
366 	    (o_hand.sa_handler == SIG_IGN) &&
367 	    (sigaction(SIGXCPU, &o_hand, &o_hand) < 0))
368 		goto out;
369 
370 	n_hand.sa_handler = SIG_IGN;
371 	if ((sigaction(SIGPIPE, &n_hand, &o_hand) < 0) ||
372 	    (sigaction(SIGXFSZ, &n_hand, &o_hand) < 0))
373 		goto out;
374 	return(0);
375 
376     out:
377 	syswarn(1, errno, "Unable to set up signal handler");
378 	return(-1);
379 }
380