1 /*	$OpenBSD: ftree.c,v 1.29 2009/10/27 23:59:22 deraadt Exp $	*/
2 /*	$NetBSD: ftree.c,v 1.4 1995/03/21 09:07:21 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 #include <sys/param.h>
38 #include <sys/time.h>
39 #include <sys/stat.h>
40 #include <unistd.h>
41 #include <string.h>
42 #include <stdio.h>
43 #include <errno.h>
44 #include <stdlib.h>
45 #include <fts.h>
46 #include <time.h>
47 #include "pax.h"
48 #include "ftree.h"
49 #include "extern.h"
50 
51 __RCSID("$MirOS: src/bin/pax/ftree.c,v 1.6 2012/05/20 16:13:17 tg Exp $");
52 
53 /*
54  * routines to interface with the fts library function.
55  *
56  * file args supplied to pax are stored on a single linked list (of type FTREE)
57  * and given to fts to be processed one at a time. pax "selects" files from
58  * the expansion of each arg into the corresponding file tree (if the arg is a
59  * directory, otherwise the node itself is just passed to pax). The selection
60  * is modified by the -n and -u flags. The user is informed when a specific
61  * file arg does not generate any selected files. -n keeps expanding the file
62  * tree arg until one of its files is selected, then skips to the next file
63  * arg. when the user does not supply the file trees as command line args to
64  * pax, they are read from stdin
65  */
66 
67 static FTS *ftsp = NULL;		/* current FTS handle */
68 static int ftsopts;			/* options to be used on fts_open */
69 static char *farray[2];			/* array for passing each arg to fts */
70 static FTREE *fthead = NULL;		/* head of linked list of file args */
71 static FTREE *fttail = NULL;		/* tail of linked list of file args */
72 static FTREE *ftcur = NULL;		/* current file arg being processed */
73 static FTSENT *ftent = NULL;		/* current file tree entry */
74 static int ftree_skip;			/* when set skip to next file arg */
75 
76 static int ftree_arg(void);
77 static char *getpathname(char *, int);
78 
79 /*
80  * ftree_start()
81  *	initialise the options passed to fts_open() during this run of pax
82  *	options are based on the selection of pax options by the user
83  *	fts_start() also calls fts_arg() to open the first valid file arg. We
84  *	also attempt to reset directory access times when -t (tflag) is set.
85  * Return:
86  *	0 if there is at least one valid file arg to process, -1 otherwise
87  */
88 
89 int
ftree_start(void)90 ftree_start(void)
91 {
92 	/*
93 	 * set up the operation mode of fts, open the first file arg. We must
94 	 * use FTS_NOCHDIR, as the user may have to open multiple archives and
95 	 * if fts did a chdir off into the boondocks, we may create an archive
96 	 * volume in an place where the user did not expect to.
97 	 */
98 	ftsopts = FTS_NOCHDIR;
99 
100 	/*
101 	 * optional user flags that effect file traversal
102 	 * -H command line symlink follow only (half follow)
103 	 * -L follow sylinks (logical)
104 	 * -P do not follow sylinks (physical). This is the default.
105 	 * -X do not cross over mount points
106 	 * -t preserve access times on files read.
107 	 * -n select only the first member of a file tree when a match is found
108 	 * -d do not extract subtrees rooted at a directory arg.
109 	 */
110 	if (Lflag)
111 		ftsopts |= FTS_LOGICAL;
112 	else
113 		ftsopts |= FTS_PHYSICAL;
114 	if (Hflag)
115 		ftsopts |= FTS_COMFOLLOW;
116 	if (Xflag)
117 		ftsopts |= FTS_XDEV;
118 
119 	if ((fthead == NULL) && ((farray[0] = malloc(PAXPATHLEN+2)) == NULL)) {
120 		paxwarn(1, "Unable to allocate memory for file name buffer");
121 		return(-1);
122 	}
123 
124 	if (ftree_arg() < 0)
125 		return(-1);
126 	if (tflag && (atdir_start() < 0))
127 		return(-1);
128 	return(0);
129 }
130 
131 /*
132  * ftree_add()
133  *	add the arg to the linked list of files to process. Each will be
134  *	processed by fts one at a time
135  * Return:
136  *	0 if added to the linked list, -1 if failed
137  */
138 
139 int
ftree_add(char * str,int chflg)140 ftree_add(char *str, int chflg)
141 {
142 	FTREE *ft;
143 	int len;
144 
145 	/*
146 	 * simple check for bad args
147 	 */
148 	if ((str == NULL) || (*str == '\0')) {
149 		paxwarn(0, "Invalid file name argument");
150 		return(-1);
151 	}
152 
153 	/*
154 	 * allocate FTREE node and add to the end of the linked list (args are
155 	 * processed in the same order they were passed to pax). Get rid of any
156 	 * trailing / the user may pass us. (watch out for / by itself).
157 	 */
158 	if ((ft = (FTREE *)malloc(sizeof(FTREE))) == NULL) {
159 		paxwarn(0, "Unable to allocate memory for filename");
160 		return(-1);
161 	}
162 
163 	if (((len = strlen(str) - 1) > 0) && (str[len] == '/'))
164 		str[len] = '\0';
165 	ft->fname = str;
166 	ft->refcnt = 0;
167 	ft->newercnt = 0;
168 	ft->chflg = chflg;
169 	ft->fow = NULL;
170 	if (fthead == NULL) {
171 		fttail = fthead = ft;
172 		return(0);
173 	}
174 	fttail->fow = ft;
175 	fttail = ft;
176 	return(0);
177 }
178 
179 /*
180  * ftree_sel()
181  *	this entry has been selected by pax. bump up reference count and handle
182  *	-n and -d processing.
183  */
184 
185 void
ftree_sel(ARCHD * arcn)186 ftree_sel(ARCHD *arcn)
187 {
188 	/*
189 	 * set reference bit for this pattern. This linked list is only used
190 	 * when file trees are supplied pax as args. The list is not used when
191 	 * the trees are read from stdin.
192 	 */
193 	if (ftcur != NULL)
194 		ftcur->refcnt = 1;
195 
196 	/*
197 	 * if -n we are done with this arg, force a skip to the next arg when
198 	 * pax asks for the next file in next_file().
199 	 * if -d we tell fts only to match the directory (if the arg is a dir)
200 	 * and not the entire file tree rooted at that point.
201 	 */
202 	if (nflag)
203 		ftree_skip = 1;
204 
205 	if (!dflag || (arcn->type != PAX_DIR))
206 		return;
207 
208 	if (ftent != NULL)
209 		(void)fts_set(ftsp, ftent, FTS_SKIP);
210 }
211 
212 /*
213  * ftree_skipped_newer()
214  *	file has been skipped because a newer file exists and -u/-D given
215  */
216 
217 void
ftree_skipped_newer(void)218 ftree_skipped_newer(void)
219 {
220 	/* skipped due to -u/-D, mark accordingly */
221 	if (ftcur != NULL)
222 		ftcur->newercnt = 1;
223 }
224 
225 /*
226  * ftree_chk()
227  *	called at end on pax execution. Prints all those file args that did not
228  *	have a selected member (reference count still 0)
229  */
230 
231 void
ftree_chk(void)232 ftree_chk(void)
233 {
234 	FTREE *ft;
235 	int wban = 0;
236 
237 	/*
238 	 * make sure all dir access times were reset.
239 	 */
240 	if (tflag)
241 		atdir_end();
242 
243 	/*
244 	 * walk down list and check reference count. Print out those members
245 	 * that never had a match
246 	 */
247 	for (ft = fthead; ft != NULL; ft = ft->fow) {
248 		if ((ft->refcnt > 0) || ft->newercnt > 0 || ft->chflg)
249 			continue;
250 		if (wban == 0) {
251 			paxwarn(1,"WARNING! These file names were not selected:");
252 			++wban;
253 		}
254 		(void)fprintf(stderr, "%s\n", ft->fname);
255 	}
256 }
257 
258 /*
259  * ftree_arg()
260  *	Get the next file arg for fts to process. Can be from either the linked
261  *	list or read from stdin when the user did not them as args to pax. Each
262  *	arg is processed until the first successful fts_open().
263  * Return:
264  *	0 when the next arg is ready to go, -1 if out of file args (or EOF on
265  *	stdin).
266  */
267 
268 static int
ftree_arg(void)269 ftree_arg(void)
270 {
271 
272 	/*
273 	 * close off the current file tree
274 	 */
275 	if (ftsp != NULL) {
276 		(void)fts_close(ftsp);
277 		ftsp = NULL;
278 	}
279 
280 	/*
281 	 * keep looping until we get a valid file tree to process. Stop when we
282 	 * reach the end of the list (or get an eof on stdin)
283 	 */
284 	for (;;) {
285 		if (fthead == NULL) {
286 			/*
287 			 * the user didn't supply any args, get the file trees
288 			 * to process from stdin;
289 			 */
290 			if (getpathname(farray[0], PAXPATHLEN+1) == NULL)
291 				return(-1);
292 		} else {
293 			/*
294 			 * the user supplied the file args as arguments to pax
295 			 */
296 			if (ftcur == NULL)
297 				ftcur = fthead;
298 			else if ((ftcur = ftcur->fow) == NULL)
299 				return(-1);
300 			if (ftcur->chflg) {
301 				/* First fchdir() back... */
302 				if (fchdir(cwdfd) < 0) {
303 					syswarn(1, errno,
304 					  "Can't fchdir to starting directory");
305 					return(-1);
306 				}
307 				if (chdir(ftcur->fname) < 0) {
308 					syswarn(1, errno, "Can't chdir to %s",
309 					    ftcur->fname);
310 					return(-1);
311 				}
312 				continue;
313 			} else
314 				farray[0] = ftcur->fname;
315 		}
316 
317 		/*
318 		 * watch it, fts wants the file arg stored in a array of char
319 		 * ptrs, with the last one a null. we use a two element array
320 		 * and set farray[0] to point at the buffer with the file name
321 		 * in it. We cannot pass all the file args to fts at one shot
322 		 * as we need to keep a handle on which file arg generates what
323 		 * files (the -n and -d flags need this). If the open is
324 		 * successful, return a 0.
325 		 */
326 		if ((ftsp = fts_open(farray, ftsopts, NULL)) != NULL)
327 			break;
328 	}
329 	return(0);
330 }
331 
332 /*
333  * next_file()
334  *	supplies the next file to process in the supplied archd structure.
335  * Return:
336  *	0 when contents of arcn have been set with the next file, -1 when done.
337  */
338 
339 int
next_file(ARCHD * arcn)340 next_file(ARCHD *arcn)
341 {
342 	int cnt;
343 	time_t atime;
344 	time_t mtime;
345 
346 	/*
347 	 * ftree_sel() might have set the ftree_skip flag if the user has the
348 	 * -n option and a file was selected from this file arg tree. (-n says
349 	 * only one member is matched for each pattern) ftree_skip being 1
350 	 * forces us to go to the next arg now.
351 	 */
352 	if (ftree_skip) {
353 		/*
354 		 * clear and go to next arg
355 		 */
356 		ftree_skip = 0;
357 		if (ftree_arg() < 0)
358 			return(-1);
359 	}
360 
361 	/*
362 	 * loop until we get a valid file to process
363 	 */
364 	for (;;) {
365 		if ((ftent = fts_read(ftsp)) == NULL) {
366 			if (errno)
367 				syswarn(1, errno, "next_file");
368 			/*
369 			 * out of files in this tree, go to next arg, if none
370 			 * we are done
371 			 */
372 			if (ftree_arg() < 0)
373 				return(-1);
374 			continue;
375 		}
376 
377 		/*
378 		 * handle each type of fts_read() flag
379 		 */
380 		switch (ftent->fts_info) {
381 		case FTS_D:
382 		case FTS_DEFAULT:
383 		case FTS_F:
384 		case FTS_SL:
385 		case FTS_SLNONE:
386 			/*
387 			 * these are all ok
388 			 */
389 			break;
390 		case FTS_DP:
391 			/*
392 			 * already saw this directory. If the user wants file
393 			 * access times reset, we use this to restore the
394 			 * access time for this directory since this is the
395 			 * last time we will see it in this file subtree
396 			 * remember to force the time (this is -t on a read
397 			 * directory, not a created directory).
398 			 */
399 			if (!tflag || (get_atdir(ftent->fts_statp->st_dev,
400 			    ftent->fts_statp->st_ino, &mtime, &atime) < 0))
401 				continue;
402 			set_ftime(ftent->fts_path, mtime, atime, 1);
403 			continue;
404 		case FTS_DC:
405 			/*
406 			 * fts claims a file system cycle
407 			 */
408 			paxwarn(1,"File system cycle found at %s",ftent->fts_path);
409 			continue;
410 		case FTS_DNR:
411 			syswarn(1, ftent->fts_errno,
412 			    "Unable to read directory %s", ftent->fts_path);
413 			continue;
414 		case FTS_ERR:
415 			syswarn(1, ftent->fts_errno,
416 			    "File system traversal error");
417 			continue;
418 		case FTS_NS:
419 		case FTS_NSOK:
420 			syswarn(1, ftent->fts_errno,
421 			    "Unable to access %s", ftent->fts_path);
422 			continue;
423 		}
424 
425 		/*
426 		 * ok got a file tree node to process. copy info into arcn
427 		 * structure (initialise as required)
428 		 */
429 		arcn->skip = 0;
430 		arcn->pad = 0;
431 		arcn->ln_nlen = 0;
432 		arcn->ln_name[0] = '\0';
433 		memcpy(&arcn->sb, ftent->fts_statp, sizeof(arcn->sb));
434 
435 		/*
436 		 * file type based set up and copy into the arcn struct
437 		 * SIDE NOTE:
438 		 * we try to reset the access time on all files and directories
439 		 * we may read when the -t flag is specified. files are reset
440 		 * when we close them after copying. we reset the directories
441 		 * when we are done with their file tree (we also clean up at
442 		 * end in case we cut short a file tree traversal). However
443 		 * there is no way to reset access times on symlinks.
444 		 */
445 		switch (S_IFMT & arcn->sb.st_mode) {
446 		case S_IFDIR:
447 			arcn->type = PAX_DIR;
448 			if (!tflag)
449 				break;
450 			add_atdir(ftent->fts_path, arcn->sb.st_dev,
451 			    arcn->sb.st_ino, arcn->sb.st_mtime,
452 			    arcn->sb.st_atime);
453 			break;
454 		case S_IFCHR:
455 			arcn->type = PAX_CHR;
456 			break;
457 		case S_IFBLK:
458 			arcn->type = PAX_BLK;
459 			break;
460 		case S_IFREG:
461 			/*
462 			 * only regular files with have data to store on the
463 			 * archive. all others will store a zero length skip.
464 			 * the skip field is used by pax for actual data it has
465 			 * to read (or skip over).
466 			 */
467 			arcn->type = PAX_REG;
468 			arcn->skip = arcn->sb.st_size;
469 			break;
470 		case S_IFLNK:
471 			arcn->type = PAX_SLK;
472 			/*
473 			 * have to read the symlink path from the file
474 			 */
475 			if ((cnt = readlink(ftent->fts_path, arcn->ln_name,
476 			    PAXPATHLEN)) < 0) {
477 				syswarn(1, errno, "Unable to read symlink %s",
478 				    ftent->fts_path);
479 				continue;
480 			}
481 			/*
482 			 * set link name length, watch out readlink does not
483 			 * always NUL terminate the link path
484 			 */
485 			arcn->ln_name[cnt] = '\0';
486 			arcn->ln_nlen = cnt;
487 			break;
488 		case S_IFSOCK:
489 			/*
490 			 * under BSD storing a socket is senseless but we will
491 			 * let the format specific write function make the
492 			 * decision of what to do with it.
493 			 */
494 			arcn->type = PAX_SCK;
495 			break;
496 		case S_IFIFO:
497 			arcn->type = PAX_FIF;
498 			break;
499 		}
500 		break;
501 	}
502 
503 	/*
504 	 * copy file name, set file name length
505 	 */
506 	arcn->nlen = strlcpy(arcn->name, ftent->fts_path, sizeof(arcn->name));
507 	if ((size_t)arcn->nlen >= sizeof(arcn->name))
508 		arcn->nlen = sizeof(arcn->name) - 1; /* XXX truncate? */
509 	arcn->org_name = ftent->fts_path;
510 	return(0);
511 }
512 
513 /*
514  * getpathname()
515  *	Reads a pathname from stdin, handling NUL- or newline-termination.
516  * Return:
517  *	NULL at end of file, otherwise the NUL-terminated buffer.
518  */
519 
520 static char *
getpathname(char * buf,int buflen)521 getpathname(char *buf, int buflen)
522 {
523 	char *bp, *ep;
524 	int ch, term;
525 
526 	if (zeroflag) {
527 		/*
528 		 * Read a NUL-terminated pathname, being especially
529 		 * paranoid about proper termination and pathname length.
530 		 */
531 		for (bp = buf, ep = buf + buflen; bp < ep; bp++) {
532 			if ((ch = getchar()) == EOF) {
533 				if (bp != buf)
534 					paxwarn(1, "Ignoring unterminated "
535 					    "pathname at EOF");
536 				return(NULL);
537 			}
538 			if ((*bp = ch) == '\0')
539 				return(buf);
540 		}
541 		/* Too long - skip this path */
542 		*--bp = '\0';
543 		term = '\0';
544 	} else {
545 		if (fgets(buf, buflen, stdin) == NULL)
546 			return(NULL);
547 		if ((bp = strchr(buf, '\n')) != NULL || feof(stdin)) {
548 			if (bp != NULL)
549 				*bp = '\0';
550 			return(buf);
551 		}
552 		/* Too long - skip this path */
553 		term = '\n';
554 	}
555 	while ((ch = getchar()) != term && ch != EOF)
556 		;
557 	paxwarn(1, "Ignoring too-long pathname: %s", buf);
558 	return(NULL);
559 }
560