1/*	$OpenBSD: pat_rep.c,v 1.30 2005/08/05 08:30:10 djm Exp $	*/
2/*	$NetBSD: pat_rep.c,v 1.4 1995/03/21 09:07:33 cgd Exp $	*/
3
4/*-
5 * Copyright (c) 1992 Keith Muller.
6 * Copyright (c) 1992, 1993
7 *	The Regents of the University of California.  All rights reserved.
8 *
9 * This code is derived from software contributed to Berkeley by
10 * Keith Muller of the University of California, San Diego.
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 *    notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 *    notice, this list of conditions and the following disclaimer in the
19 *    documentation and/or other materials provided with the distribution.
20 * 3. Neither the name of the University nor the names of its contributors
21 *    may be used to endorse or promote products derived from this software
22 *    without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 */
36
37#ifndef lint
38#if 0
39static const char sccsid[] = "@(#)pat_rep.c	8.2 (Berkeley) 4/18/94";
40#else
41static const char rcsid[] = "$OpenBSD: pat_rep.c,v 1.30 2005/08/05 08:30:10 djm Exp $";
42#endif
43#endif /* not lint */
44
45#include <sys/types.h>
46#include <sys/time.h>
47#include <sys/stat.h>
48#include <sys/param.h>
49#include <stdio.h>
50#include <string.h>
51#include <unistd.h>
52#include <stdlib.h>
53#include <errno.h>
54#include <regex.h>
55#include "pax.h"
56#include "pat_rep.h"
57#include "extern.h"
58
59/*
60 * routines to handle pattern matching, name modification (regular expression
61 * substitution and interactive renames), and destination name modification for
62 * copy (-rw). Both file name and link names are adjusted as required in these
63 * routines.
64 */
65
66#define MAXSUBEXP	10		/* max subexpressions, DO NOT CHANGE */
67static PATTERN *pathead = NULL;		/* file pattern match list head */
68static PATTERN *pattail = NULL;		/* file pattern match list tail */
69static REPLACE *rephead = NULL;		/* replacement string list head */
70static REPLACE *reptail = NULL;		/* replacement string list tail */
71
72static int rep_name(char *, size_t, int *, int);
73int tty_rename(ARCHD *);
74static int fix_path(char *, int *, char *, int);
75static int fn_match(char *, char *, char **);
76static char * range_match(char *, int);
77static int resub(regex_t *, regmatch_t *, char *, char *, char *, char *);
78
79/*
80 * rep_add()
81 *	parses the -s replacement string; compiles the regular expression
82 *	and stores the compiled value and it's replacement string together in
83 *	replacement string list. Input to this function is of the form:
84 *		/old/new/pg
85 *	The first char in the string specifies the delimiter used by this
86 *	replacement string. "Old" is a regular expression in "ed" format which
87 *	is compiled by regcomp() and is applied to filenames. "new" is the
88 *	substitution string; p and g are options flags for printing and global
89 *	replacement (over the single filename)
90 * Return:
91 *	0 if a proper replacement string and regular expression was added to
92 *	the list of replacement patterns; -1 otherwise.
93 */
94
95int
96rep_add(char *str)
97{
98	char *pt1;
99	char *pt2;
100	REPLACE *rep;
101	int res;
102	char rebuf[BUFSIZ];
103
104	/*
105	 * throw out the bad parameters
106	 */
107	if ((str == NULL) || (*str == '\0')) {
108		paxwarn(1, "Empty replacement string");
109		return(-1);
110	}
111
112	/*
113	 * first character in the string specifies what the delimiter is for
114	 * this expression
115	 */
116	for (pt1 = str+1; *pt1; pt1++) {
117		if (*pt1 == '\\') {
118			pt1++;
119			continue;
120		}
121		if (*pt1 == *str)
122			break;
123	}
124	if (*pt1 == '\0') {
125		paxwarn(1, "Invalid replacement string %s", str);
126		return(-1);
127	}
128
129	/*
130	 * allocate space for the node that handles this replacement pattern
131	 * and split out the regular expression and try to compile it
132	 */
133	if ((rep = (REPLACE *)malloc(sizeof(REPLACE))) == NULL) {
134		paxwarn(1, "Unable to allocate memory for replacement string");
135		return(-1);
136	}
137
138	*pt1 = '\0';
139	if ((res = regcomp(&(rep->rcmp), str+1, 0)) != 0) {
140		regerror(res, &(rep->rcmp), rebuf, sizeof(rebuf));
141		paxwarn(1, "%s while compiling regular expression %s", rebuf, str);
142		(void)free((char *)rep);
143		return(-1);
144	}
145
146	/*
147	 * put the delimiter back in case we need an error message and
148	 * locate the delimiter at the end of the replacement string
149	 * we then point the node at the new substitution string
150	 */
151	*pt1++ = *str;
152	for (pt2 = pt1; *pt2; pt2++) {
153		if (*pt2 == '\\') {
154			pt2++;
155			continue;
156		}
157		if (*pt2 == *str)
158			break;
159	}
160	if (*pt2 == '\0') {
161		regfree(&(rep->rcmp));
162		(void)free((char *)rep);
163		paxwarn(1, "Invalid replacement string %s", str);
164		return(-1);
165	}
166
167	*pt2 = '\0';
168	rep->nstr = pt1;
169	pt1 = pt2++;
170	rep->flgs = 0;
171
172	/*
173	 * set the options if any
174	 */
175	while (*pt2 != '\0') {
176		switch (*pt2) {
177		case 'g':
178		case 'G':
179			rep->flgs  |= GLOB;
180			break;
181		case 'p':
182		case 'P':
183			rep->flgs  |= PRNT;
184			break;
185		default:
186			regfree(&(rep->rcmp));
187			(void)free((char *)rep);
188			*pt1 = *str;
189			paxwarn(1, "Invalid replacement string option %s", str);
190			return(-1);
191		}
192		++pt2;
193	}
194
195	/*
196	 * all done, link it in at the end
197	 */
198	rep->fow = NULL;
199	if (rephead == NULL) {
200		reptail = rephead = rep;
201		return(0);
202	}
203	reptail->fow = rep;
204	reptail = rep;
205	return(0);
206}
207
208/*
209 * pat_add()
210 *	add a pattern match to the pattern match list. Pattern matches are used
211 *	to select which archive members are extracted. (They appear as
212 *	arguments to pax in the list and read modes). If no patterns are
213 *	supplied to pax, all members in the archive will be selected (and the
214 *	pattern match list is empty).
215 * Return:
216 *	0 if the pattern was added to the list, -1 otherwise
217 */
218
219int
220pat_add(char *str, char *chdname)
221{
222	PATTERN *pt;
223
224	/*
225	 * throw out the junk
226	 */
227	if ((str == NULL) || (*str == '\0')) {
228		paxwarn(1, "Empty pattern string");
229		return(-1);
230	}
231
232	/*
233	 * allocate space for the pattern and store the pattern. the pattern is
234	 * part of argv so do not bother to copy it, just point at it. Add the
235	 * node to the end of the pattern list
236	 */
237	if ((pt = (PATTERN *)malloc(sizeof(PATTERN))) == NULL) {
238		paxwarn(1, "Unable to allocate memory for pattern string");
239		return(-1);
240	}
241
242	pt->pstr = str;
243	pt->pend = NULL;
244	pt->plen = strlen(str);
245	pt->fow = NULL;
246	pt->flgs = 0;
247	pt->chdname = chdname;
248
249	if (pathead == NULL) {
250		pattail = pathead = pt;
251		return(0);
252	}
253	pattail->fow = pt;
254	pattail = pt;
255	return(0);
256}
257
258/*
259 * pat_chk()
260 *	complain if any the user supplied pattern did not result in a match to
261 *	a selected archive member.
262 */
263
264void
265pat_chk(void)
266{
267	PATTERN *pt;
268	int wban = 0;
269
270	/*
271	 * walk down the list checking the flags to make sure MTCH was set,
272	 * if not complain
273	 */
274	for (pt = pathead; pt != NULL; pt = pt->fow) {
275		if (pt->flgs & MTCH)
276			continue;
277		if (!wban) {
278			paxwarn(1, "WARNING! These patterns were not matched:");
279			++wban;
280		}
281		(void)fprintf(stderr, "%s\n", pt->pstr);
282	}
283}
284
285/*
286 * pat_sel()
287 *	the archive member which matches a pattern was selected. Mark the
288 *	pattern as having selected an archive member. arcn->pat points at the
289 *	pattern that was matched. arcn->pat is set in pat_match()
290 *
291 *	NOTE: When the -c option is used, we are called when there was no match
292 *	by pat_match() (that means we did match before the inverted sense of
293 *	the logic). Now this seems really strange at first, but with -c we
294 *	need to keep track of those patterns that cause an archive member to NOT
295 *	be selected (it found an archive member with a specified pattern)
296 * Return:
297 *	0 if the pattern pointed at by arcn->pat was tagged as creating a
298 *	match, -1 otherwise.
299 */
300
301int
302pat_sel(ARCHD *arcn)
303{
304	PATTERN *pt;
305	PATTERN **ppt;
306	int len;
307
308	/*
309	 * if no patterns just return
310	 */
311	if ((pathead == NULL) || ((pt = arcn->pat) == NULL))
312		return(0);
313
314	/*
315	 * when we are NOT limited to a single match per pattern mark the
316	 * pattern and return
317	 */
318	if (!nflag) {
319		pt->flgs |= MTCH;
320		return(0);
321	}
322
323	/*
324	 * we reach this point only when we allow a single selected match per
325	 * pattern, if the pattern matches a directory and we do not have -d
326	 * (dflag) we are done with this pattern. We may also be handed a file
327	 * in the subtree of a directory. in that case when we are operating
328	 * with -d, this pattern was already selected and we are done
329	 */
330	if (pt->flgs & DIR_MTCH)
331		return(0);
332
333	if (!dflag && ((pt->pend != NULL) || (arcn->type == PAX_DIR))) {
334		/*
335		 * ok we matched a directory and we are allowing
336		 * subtree matches but because of the -n only its children will
337		 * match. This is tagged as a DIR_MTCH type.
338		 * WATCH IT, the code assumes that pt->pend points
339		 * into arcn->name and arcn->name has not been modified.
340		 * If not we will have a big mess. Yup this is another kludge
341		 */
342
343		/*
344		 * if this was a prefix match, remove trailing part of path
345		 * so we can copy it. Future matches will be exact prefix match
346		 */
347		if (pt->pend != NULL)
348			*pt->pend = '\0';
349
350		if ((pt->pstr = strdup(arcn->name)) == NULL) {
351			paxwarn(1, "Pattern select out of memory");
352			if (pt->pend != NULL)
353				*pt->pend = '/';
354			pt->pend = NULL;
355			return(-1);
356		}
357
358		/*
359		 * put the trailing / back in the source string
360		 */
361		if (pt->pend != NULL) {
362			*pt->pend = '/';
363			pt->pend = NULL;
364		}
365		pt->plen = strlen(pt->pstr);
366
367		/*
368		 * strip off any trailing /, this should really never happen
369		 */
370		len = pt->plen - 1;
371		if (*(pt->pstr + len) == '/') {
372			*(pt->pstr + len) = '\0';
373			pt->plen = len;
374		}
375		pt->flgs = DIR_MTCH | MTCH;
376		arcn->pat = pt;
377		return(0);
378	}
379
380	/*
381	 * we are then done with this pattern, so we delete it from the list
382	 * because it can never be used for another match.
383	 * Seems kind of strange to do for a -c, but the pax spec is really
384	 * vague on the interaction of -c, -n and -d. We assume that when -c
385	 * and the pattern rejects a member (i.e. it matched it) it is done.
386	 * In effect we place the order of the flags as having -c last.
387	 */
388	pt = pathead;
389	ppt = &pathead;
390	while ((pt != NULL) && (pt != arcn->pat)) {
391		ppt = &(pt->fow);
392		pt = pt->fow;
393	}
394
395	if (pt == NULL) {
396		/*
397		 * should never happen....
398		 */
399		paxwarn(1, "Pattern list inconsistent");
400		return(-1);
401	}
402	*ppt = pt->fow;
403	(void)free((char *)pt);
404	arcn->pat = NULL;
405	return(0);
406}
407
408/*
409 * pat_match()
410 *	see if this archive member matches any supplied pattern, if a match
411 *	is found, arcn->pat is set to point at the potential pattern. Later if
412 *	this archive member is "selected" we process and mark the pattern as
413 *	one which matched a selected archive member (see pat_sel())
414 * Return:
415 *	0 if this archive member should be processed, 1 if it should be
416 *	skipped and -1 if we are done with all patterns (and pax should quit
417 *	looking for more members)
418 */
419
420int
421pat_match(ARCHD *arcn)
422{
423	PATTERN *pt;
424
425	arcn->pat = NULL;
426
427	/*
428	 * if there are no more patterns and we have -n (and not -c) we are
429	 * done. otherwise with no patterns to match, matches all
430	 */
431	if (pathead == NULL) {
432		if (nflag && !cflag)
433			return(-1);
434		return(0);
435	}
436
437	/*
438	 * have to search down the list one at a time looking for a match.
439	 */
440	pt = pathead;
441	while (pt != NULL) {
442		/*
443		 * check for a file name match unless we have DIR_MTCH set in
444		 * this pattern then we want a prefix match
445		 */
446		if (pt->flgs & DIR_MTCH) {
447			/*
448			 * this pattern was matched before to a directory
449			 * as we must have -n set for this (but not -d). We can
450			 * only match CHILDREN of that directory so we must use
451			 * an exact prefix match (no wildcards).
452			 */
453			if ((arcn->name[pt->plen] == '/') &&
454			    (strncmp(pt->pstr, arcn->name, pt->plen) == 0))
455				break;
456		} else if (fn_match(pt->pstr, arcn->name, &pt->pend) == 0)
457			break;
458		pt = pt->fow;
459	}
460
461	/*
462	 * return the result, remember that cflag (-c) inverts the sense of a
463	 * match
464	 */
465	if (pt == NULL)
466		return(cflag ? 0 : 1);
467
468	/*
469	 * we had a match, now when we invert the sense (-c) we reject this
470	 * member. However we have to tag the pattern a being successful, (in a
471	 * match, not in selecting an archive member) so we call pat_sel() here.
472	 */
473	arcn->pat = pt;
474	if (!cflag)
475		return(0);
476
477	if (pat_sel(arcn) < 0)
478		return(-1);
479	arcn->pat = NULL;
480	return(1);
481}
482
483/*
484 * fn_match()
485 * Return:
486 *	0 if this archive member should be processed, 1 if it should be
487 *	skipped and -1 if we are done with all patterns (and pax should quit
488 *	looking for more members)
489 *	Note: *pend may be changed to show where the prefix ends.
490 */
491
492static int
493fn_match(char *pattern, char *string, char **pend)
494{
495	char c;
496	char test;
497
498	*pend = NULL;
499	for (;;) {
500		switch (c = *pattern++) {
501		case '\0':
502			/*
503			 * Ok we found an exact match
504			 */
505			if (*string == '\0')
506				return(0);
507
508			/*
509			 * Check if it is a prefix match
510			 */
511			if ((dflag == 1) || (*string != '/'))
512				return(-1);
513
514			/*
515			 * It is a prefix match, remember where the trailing
516			 * / is located
517			 */
518			*pend = string;
519			return(0);
520		case '?':
521			if ((*string++) == '\0')
522				return (-1);
523			break;
524		case '*':
525			c = *pattern;
526			/*
527			 * Collapse multiple *'s.
528			 */
529			while (c == '*')
530				c = *++pattern;
531
532			/*
533			 * Optimized hack for pattern with a * at the end
534			 */
535			if (c == '\0')
536				return (0);
537
538			/*
539			 * General case, use recursion.
540			 */
541			while ((*string) != '\0') {
542				if (!fn_match(pattern, string, pend))
543					return (0);
544				++string;
545			}
546			return (-1);
547		case '[':
548			/*
549			 * range match
550			 */
551			if (((test = *string++) == '\0') ||
552			    ((pattern = range_match(pattern, test)) == NULL))
553				return (-1);
554			break;
555		case '\\':
556		default:
557			if (c != *string++)
558				return (-1);
559			break;
560		}
561	}
562	/* NOTREACHED */
563}
564
565static char *
566range_match(char *pattern, int test)
567{
568	char c;
569	char c2;
570	int negate;
571	int ok = 0;
572
573	if ((negate = (*pattern == '!')) != 0)
574		++pattern;
575
576	while ((c = *pattern++) != ']') {
577		/*
578		 * Illegal pattern
579		 */
580		if (c == '\0')
581			return (NULL);
582
583		if ((*pattern == '-') && ((c2 = pattern[1]) != '\0') &&
584		    (c2 != ']')) {
585			if ((c <= test) && (test <= c2))
586				ok = 1;
587			pattern += 2;
588		} else if (c == test)
589			ok = 1;
590	}
591	return (ok == negate ? NULL : pattern);
592}
593
594/*
595 * mod_name()
596 *	modify a selected file name. first attempt to apply replacement string
597 *	expressions, then apply interactive file rename. We apply replacement
598 *	string expressions to both filenames and file links (if we didn't the
599 *	links would point to the wrong place, and we could never be able to
600 *	move an archive that has a file link in it). When we rename files
601 *	interactively, we store that mapping (old name to user input name) so
602 *	if we spot any file links to the old file name in the future, we will
603 *	know exactly how to fix the file link.
604 * Return:
605 *	0 continue to  process file, 1 skip this file, -1 pax is finished
606 */
607
608int
609mod_name(ARCHD *arcn)
610{
611	int res = 0;
612
613	/*
614	 * Strip off leading '/' if appropriate.
615	 * Currently, this option is only set for the tar format.
616	 */
617	while (rmleadslash && arcn->name[0] == '/') {
618		if (arcn->name[1] == '\0') {
619			arcn->name[0] = '.';
620		} else {
621			(void)memmove(arcn->name, &arcn->name[1],
622			    strlen(arcn->name));
623			arcn->nlen--;
624		}
625		if (rmleadslash < 2) {
626			rmleadslash = 2;
627			paxwarn(0, "Removing leading / from absolute path names in the archive");
628		}
629	}
630	while (rmleadslash && arcn->ln_name[0] == '/' &&
631	    (arcn->type == PAX_HLK || arcn->type == PAX_HRG)) {
632		if (arcn->ln_name[1] == '\0') {
633			arcn->ln_name[0] = '.';
634		} else {
635			(void)memmove(arcn->ln_name, &arcn->ln_name[1],
636			    strlen(arcn->ln_name));
637			arcn->ln_nlen--;
638		}
639		if (rmleadslash < 2) {
640			rmleadslash = 2;
641			paxwarn(0, "Removing leading / from absolute path names in the archive");
642		}
643	}
644
645	/*
646	 * IMPORTANT: We have a problem. what do we do with symlinks?
647	 * Modifying a hard link name makes sense, as we know the file it
648	 * points at should have been seen already in the archive (and if it
649	 * wasn't seen because of a read error or a bad archive, we lose
650	 * anyway). But there are no such requirements for symlinks. On one
651	 * hand the symlink that refers to a file in the archive will have to
652	 * be modified to so it will still work at its new location in the
653	 * file system. On the other hand a symlink that points elsewhere (and
654	 * should continue to do so) should not be modified. There is clearly
655	 * no perfect solution here. So we handle them like hardlinks. Clearly
656	 * a replacement made by the interactive rename mapping is very likely
657	 * to be correct since it applies to a single file and is an exact
658	 * match. The regular expression replacements are a little harder to
659	 * justify though. We claim that the symlink name is only likely
660	 * to be replaced when it points within the file tree being moved and
661	 * in that case it should be modified. what we really need to do is to
662	 * call an oracle here. :)
663	 */
664	if (rephead != NULL) {
665		/*
666		 * we have replacement strings, modify the name and the link
667		 * name if any.
668		 */
669		if ((res = rep_name(arcn->name, sizeof(arcn->name), &(arcn->nlen), 1)) != 0)
670			return(res);
671
672		if (((arcn->type == PAX_SLK) || (arcn->type == PAX_HLK) ||
673		    (arcn->type == PAX_HRG)) &&
674		    ((res = rep_name(arcn->ln_name, sizeof(arcn->ln_name), &(arcn->ln_nlen), 0)) != 0))
675			return(res);
676	}
677
678	if (iflag) {
679		/*
680		 * perform interactive file rename, then map the link if any
681		 */
682		if ((res = tty_rename(arcn)) != 0)
683			return(res);
684		if ((arcn->type == PAX_SLK) || (arcn->type == PAX_HLK) ||
685		    (arcn->type == PAX_HRG))
686			sub_name(arcn->ln_name, &(arcn->ln_nlen), sizeof(arcn->ln_name));
687	}
688	return(res);
689}
690
691/*
692 * tty_rename()
693 *	Prompt the user for a replacement file name. A "." keeps the old name,
694 *	a empty line skips the file, and an EOF on reading the tty, will cause
695 *	pax to stop processing and exit. Otherwise the file name input, replaces
696 *	the old one.
697 * Return:
698 *	0 process this file, 1 skip this file, -1 we need to exit pax
699 */
700
701int
702tty_rename(ARCHD *arcn)
703{
704	char tmpname[PAXPATHLEN+2];
705	int res;
706
707	/*
708	 * prompt user for the replacement name for a file, keep trying until
709	 * we get some reasonable input. Archives may have more than one file
710	 * on them with the same name (from updates etc). We print verbose info
711	 * on the file so the user knows what is up.
712	 */
713	tty_prnt("\nATTENTION: %s interactive file rename operation.\n", argv0);
714
715	for (;;) {
716		ls_tty(arcn);
717		tty_prnt("Input new name, or a \".\" to keep the old name, ");
718		tty_prnt("or a \"return\" to skip this file.\n");
719		tty_prnt("Input > ");
720		if (tty_read(tmpname, sizeof(tmpname)) < 0)
721			return(-1);
722		if (strcmp(tmpname, "..") == 0) {
723			tty_prnt("Try again, illegal file name: ..\n");
724			continue;
725		}
726		if (strlen(tmpname) > PAXPATHLEN) {
727			tty_prnt("Try again, file name too long\n");
728			continue;
729		}
730		break;
731	}
732
733	/*
734	 * empty file name, skips this file. a "." leaves it alone
735	 */
736	if (tmpname[0] == '\0') {
737		tty_prnt("Skipping file.\n");
738		return(1);
739	}
740	if ((tmpname[0] == '.') && (tmpname[1] == '\0')) {
741		tty_prnt("Processing continues, name unchanged.\n");
742		return(0);
743	}
744
745	/*
746	 * ok the name changed. We may run into links that point at this
747	 * file later. we have to remember where the user sent the file
748	 * in order to repair any links.
749	 */
750	tty_prnt("Processing continues, name changed to: %s\n", tmpname);
751	res = add_name(arcn->name, arcn->nlen, tmpname);
752	arcn->nlen = strlcpy(arcn->name, tmpname, sizeof(arcn->name));
753	if (arcn->nlen >= sizeof(arcn->name))
754		arcn->nlen = sizeof(arcn->name) - 1; /* XXX truncate? */
755	if (res < 0)
756		return(-1);
757	return(0);
758}
759
760/*
761 * set_dest()
762 *	fix up the file name and the link name (if any) so this file will land
763 *	in the destination directory (used during copy() -rw).
764 * Return:
765 *	0 if ok, -1 if failure (name too long)
766 */
767
768int
769set_dest(ARCHD *arcn, char *dest_dir, int dir_len)
770{
771	if (fix_path(arcn->name, &(arcn->nlen), dest_dir, dir_len) < 0)
772		return(-1);
773
774	/*
775	 * It is really hard to deal with symlinks here, we cannot be sure
776	 * if the name they point was moved (or will be moved). It is best to
777	 * leave them alone.
778	 */
779	if ((arcn->type != PAX_HLK) && (arcn->type != PAX_HRG))
780		return(0);
781
782	if (fix_path(arcn->ln_name, &(arcn->ln_nlen), dest_dir, dir_len) < 0)
783		return(-1);
784	return(0);
785}
786
787/*
788 * fix_path
789 *	concatenate dir_name and or_name and store the result in or_name (if
790 *	it fits). This is one ugly function.
791 * Return:
792 *	0 if ok, -1 if the final name is too long
793 */
794
795static int
796fix_path(char *or_name, int *or_len, char *dir_name, int dir_len)
797{
798	char *src;
799	char *dest;
800	char *start;
801	int len;
802
803	/*
804	 * we shift the or_name to the right enough to tack in the dir_name
805	 * at the front. We make sure we have enough space for it all before
806	 * we start. since dest always ends in a slash, we skip of or_name
807	 * if it also starts with one.
808	 */
809	start = or_name;
810	src = start + *or_len;
811	dest = src + dir_len;
812	if (*start == '/') {
813		++start;
814		--dest;
815	}
816	if ((len = dest - or_name) > PAXPATHLEN) {
817		paxwarn(1, "File name %s/%s, too long", dir_name, start);
818		return(-1);
819	}
820	*or_len = len;
821
822	/*
823	 * enough space, shift
824	 */
825	while (src >= start)
826		*dest-- = *src--;
827	src = dir_name + dir_len - 1;
828
829	/*
830	 * splice in the destination directory name
831	 */
832	while (src >= dir_name)
833		*dest-- = *src--;
834
835	*(or_name + len) = '\0';
836	return(0);
837}
838
839/*
840 * rep_name()
841 *	walk down the list of replacement strings applying each one in order.
842 *	when we find one with a successful substitution, we modify the name
843 *	as specified. if required, we print the results. if the resulting name
844 *	is empty, we will skip this archive member. We use the regexp(3)
845 *	routines (regexp() ought to win a prize as having the most cryptic
846 *	library function manual page).
847 *	--Parameters--
848 *	name is the file name we are going to apply the regular expressions to
849 *	(and may be modified)
850 *	nsize is the size of the name buffer.
851 *	nlen is the length of this name (and is modified to hold the length of
852 *	the final string).
853 *	prnt is a flag that says whether to print the final result.
854 * Return:
855 *	0 if substitution was successful, 1 if we are to skip the file (the name
856 *	ended up empty)
857 */
858
859static int
860rep_name(char *name, size_t nsize, int *nlen, int prnt)
861{
862	REPLACE *pt;
863	char *inpt;
864	char *outpt;
865	char *endpt;
866	char *rpt;
867	int found = 0;
868	int res;
869	regmatch_t pm[MAXSUBEXP];
870	char nname[PAXPATHLEN+1];	/* final result of all replacements */
871	char buf1[PAXPATHLEN+1];	/* where we work on the name */
872
873	/*
874	 * copy the name into buf1, where we will work on it. We need to keep
875	 * the orig string around so we can print out the result of the final
876	 * replacement. We build up the final result in nname. inpt points at
877	 * the string we apply the regular expression to. prnt is used to
878	 * suppress printing when we handle replacements on the link field
879	 * (the user already saw that substitution go by)
880	 */
881	pt = rephead;
882	(void)strlcpy(buf1, name, sizeof(buf1));
883	inpt = buf1;
884	outpt = nname;
885	endpt = outpt + PAXPATHLEN;
886
887	/*
888	 * try each replacement string in order
889	 */
890	while (pt != NULL) {
891		do {
892			char *oinpt = inpt;
893			/*
894			 * check for a successful substitution, if not go to
895			 * the next pattern, or cleanup if we were global
896			 */
897			if (regexec(&(pt->rcmp), inpt, MAXSUBEXP, pm, 0) != 0)
898				break;
899
900			/*
901			 * ok we found one. We have three parts, the prefix
902			 * which did not match, the section that did and the
903			 * tail (that also did not match). Copy the prefix to
904			 * the final output buffer (watching to make sure we
905			 * do not create a string too long).
906			 */
907			found = 1;
908			rpt = inpt + pm[0].rm_so;
909
910			while ((inpt < rpt) && (outpt < endpt))
911				*outpt++ = *inpt++;
912			if (outpt == endpt)
913				break;
914
915			/*
916			 * for the second part (which matched the regular
917			 * expression) apply the substitution using the
918			 * replacement string and place it the prefix in the
919			 * final output. If we have problems, skip it.
920			 */
921			if ((res = resub(&(pt->rcmp),pm,pt->nstr,oinpt,outpt,endpt))
922			    < 0) {
923				if (prnt)
924					paxwarn(1, "Replacement name error %s",
925					    name);
926				return(1);
927			}
928			outpt += res;
929
930			/*
931			 * we set up to look again starting at the first
932			 * character in the tail (of the input string right
933			 * after the last character matched by the regular
934			 * expression (inpt always points at the first char in
935			 * the string to process). If we are not doing a global
936			 * substitution, we will use inpt to copy the tail to
937			 * the final result. Make sure we do not overrun the
938			 * output buffer
939			 */
940			inpt += pm[0].rm_eo - pm[0].rm_so;
941
942			if ((outpt == endpt) || (*inpt == '\0'))
943				break;
944
945			/*
946			 * if the user wants global we keep trying to
947			 * substitute until it fails, then we are done.
948			 */
949		} while (pt->flgs & GLOB);
950
951		if (found)
952			break;
953
954		/*
955		 * a successful substitution did NOT occur, try the next one
956		 */
957		pt = pt->fow;
958	}
959
960	if (found) {
961		/*
962		 * we had a substitution, copy the last tail piece (if there is
963		 * room) to the final result
964		 */
965		while ((outpt < endpt) && (*inpt != '\0'))
966			*outpt++ = *inpt++;
967
968		*outpt = '\0';
969		if ((outpt == endpt) && (*inpt != '\0')) {
970			if (prnt)
971				paxwarn(1,"Replacement name too long %s >> %s",
972				    name, nname);
973			return(1);
974		}
975
976		/*
977		 * inform the user of the result if wanted
978		 */
979		if (prnt && (pt->flgs & PRNT)) {
980			if (*nname == '\0')
981				(void)fprintf(stderr,"%s >> <empty string>\n",
982				    name);
983			else
984				(void)fprintf(stderr,"%s >> %s\n", name, nname);
985		}
986
987		/*
988		 * if empty inform the caller this file is to be skipped
989		 * otherwise copy the new name over the orig name and return
990		 */
991		if (*nname == '\0')
992			return(1);
993		*nlen = strlcpy(name, nname, nsize);
994	}
995	return(0);
996}
997
998/*
999 * resub()
1000 *	apply the replacement to the matched expression. expand out the old
1001 *	style ed(1) subexpression expansion.
1002 * Return:
1003 *	-1 if error, or the number of characters added to the destination.
1004 */
1005
1006static int
1007resub(regex_t *rp, regmatch_t *pm, char *src, char *inpt, char *dest,
1008	char *destend)
1009{
1010	char *spt;
1011	char *dpt;
1012	char c;
1013	regmatch_t *pmpt;
1014	int len;
1015	int subexcnt;
1016
1017	spt =  src;
1018	dpt = dest;
1019	subexcnt = rp->re_nsub;
1020	while ((dpt < destend) && ((c = *spt++) != '\0')) {
1021		/*
1022		 * see if we just have an ordinary replacement character
1023		 * or we refer to a subexpression.
1024		 */
1025		if (c == '&') {
1026			pmpt = pm;
1027		} else if ((c == '\\') && (*spt >= '0') && (*spt <= '9')) {
1028			/*
1029			 * make sure there is a subexpression as specified
1030			 */
1031			if ((len = *spt++ - '0') > subexcnt)
1032				return(-1);
1033			pmpt = pm + len;
1034		} else {
1035			/*
1036			 * Ordinary character, just copy it
1037			 */
1038			if ((c == '\\') && (*spt != '\0'))
1039				c = *spt++;
1040			*dpt++ = c;
1041			continue;
1042		}
1043
1044		/*
1045		 * continue if the subexpression is bogus
1046		 */
1047		if ((pmpt->rm_so < 0) || (pmpt->rm_eo < 0) ||
1048		    ((len = (int)(pmpt->rm_eo - pmpt->rm_so)) <= 0))
1049			continue;
1050
1051		/*
1052		 * copy the subexpression to the destination.
1053		 * fail if we run out of space or the match string is damaged
1054		 */
1055		if (len > (destend - dpt))
1056			len = destend - dpt;
1057		strncpy(dpt, inpt + pmpt->rm_so, len);
1058		dpt += len;
1059	}
1060	return(dpt - dest);
1061}
1062