Remove not needed void casts.
[dragonfly.git] / bin / pax / tables.c
CommitLineData
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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.
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36 *
37 * @(#)tables.c 8.1 (Berkeley) 5/31/93
38 * $FreeBSD: src/bin/pax/tables.c,v 1.13.2.1 2001/08/01 05:03:12 obrien Exp $
57fed2af 39 * $DragonFly: src/bin/pax/tables.c,v 1.6 2004/11/07 20:54:51 eirikn Exp $
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40 */
41
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42#include <sys/types.h>
43#include <sys/time.h>
44#include <sys/stat.h>
45#include <sys/fcntl.h>
46#include <errno.h>
47#include <stdio.h>
48#include <stdlib.h>
49#include <string.h>
50#include <unistd.h>
51#include "pax.h"
52#include "tables.h"
53#include "extern.h"
54
55/*
56 * Routines for controlling the contents of all the different databases pax
57 * keeps. Tables are dynamically created only when they are needed. The
58 * goal was speed and the ability to work with HUGE archives. The databases
59 * were kept simple, but do have complex rules for when the contents change.
60 * As of this writing, the POSIX library functions were more complex than
61 * needed for this application (pax databases have very short lifetimes and
62 * do not survive after pax is finished). Pax is required to handle very
63 * large archives. These database routines carefully combine memory usage and
64 * temporary file storage in ways which will not significantly impact runtime
65 * performance while allowing the largest possible archives to be handled.
66 * Trying to force the fit to the POSIX databases routines was not considered
67 * time well spent.
68 */
69
70static HRDLNK **ltab = NULL; /* hard link table for detecting hard links */
71static FTM **ftab = NULL; /* file time table for updating arch */
72static NAMT **ntab = NULL; /* interactive rename storage table */
73static DEVT **dtab = NULL; /* device/inode mapping tables */
74static ATDIR **atab = NULL; /* file tree directory time reset table */
75static int dirfd = -1; /* storage for setting created dir time/mode */
76static u_long dircnt; /* entries in dir time/mode storage */
77static int ffd = -1; /* tmp file for file time table name storage */
78
9dbf638f 79static DEVT *chk_dev (dev_t, int);
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80
81/*
82 * hard link table routines
83 *
84 * The hard link table tries to detect hard links to files using the device and
85 * inode values. We do this when writing an archive, so we can tell the format
86 * write routine that this file is a hard link to another file. The format
87 * write routine then can store this file in whatever way it wants (as a hard
88 * link if the format supports that like tar, or ignore this info like cpio).
89 * (Actually a field in the format driver table tells us if the format wants
90 * hard link info. if not, we do not waste time looking for them). We also use
91 * the same table when reading an archive. In that situation, this table is
92 * used by the format read routine to detect hard links from stored dev and
93 * inode numbers (like cpio). This will allow pax to create a link when one
94 * can be detected by the archive format.
95 */
96
97/*
98 * lnk_start
99 * Creates the hard link table.
100 * Return:
101 * 0 if created, -1 if failure
102 */
103
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104int
105lnk_start(void)
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106{
107 if (ltab != NULL)
108 return(0);
109 if ((ltab = (HRDLNK **)calloc(L_TAB_SZ, sizeof(HRDLNK *))) == NULL) {
110 paxwarn(1, "Cannot allocate memory for hard link table");
111 return(-1);
112 }
113 return(0);
114}
115
116/*
117 * chk_lnk()
118 * Looks up entry in hard link hash table. If found, it copies the name
119 * of the file it is linked to (we already saw that file) into ln_name.
120 * lnkcnt is decremented and if goes to 1 the node is deleted from the
121 * database. (We have seen all the links to this file). If not found,
122 * we add the file to the database if it has the potential for having
123 * hard links to other files we may process (it has a link count > 1)
124 * Return:
125 * if found returns 1; if not found returns 0; -1 on error
126 */
127
984263bc 128int
86a586bb 129chk_lnk(ARCHD *arcn)
984263bc 130{
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131 HRDLNK *pt;
132 HRDLNK **ppt;
133 u_int indx;
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134
135 if (ltab == NULL)
136 return(-1);
137 /*
138 * ignore those nodes that cannot have hard links
139 */
140 if ((arcn->type == PAX_DIR) || (arcn->sb.st_nlink <= 1))
141 return(0);
142
143 /*
144 * hash inode number and look for this file
145 */
146 indx = ((unsigned)arcn->sb.st_ino) % L_TAB_SZ;
147 if ((pt = ltab[indx]) != NULL) {
148 /*
149 * it's hash chain in not empty, walk down looking for it
150 */
151 ppt = &(ltab[indx]);
152 while (pt != NULL) {
153 if ((pt->ino == arcn->sb.st_ino) &&
154 (pt->dev == arcn->sb.st_dev))
155 break;
156 ppt = &(pt->fow);
157 pt = pt->fow;
158 }
159
160 if (pt != NULL) {
161 /*
162 * found a link. set the node type and copy in the
163 * name of the file it is to link to. we need to
164 * handle hardlinks to regular files differently than
165 * other links.
166 */
167 arcn->ln_nlen = l_strncpy(arcn->ln_name, pt->name,
168 sizeof(arcn->ln_name) - 1);
169 arcn->ln_name[arcn->ln_nlen] = '\0';
170 if (arcn->type == PAX_REG)
171 arcn->type = PAX_HRG;
172 else
173 arcn->type = PAX_HLK;
174
175 /*
176 * if we have found all the links to this file, remove
177 * it from the database
178 */
179 if (--pt->nlink <= 1) {
180 *ppt = pt->fow;
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181 free((char *)pt->name);
182 free((char *)pt);
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183 }
184 return(1);
185 }
186 }
187
188 /*
189 * we never saw this file before. It has links so we add it to the
190 * front of this hash chain
191 */
192 if ((pt = (HRDLNK *)malloc(sizeof(HRDLNK))) != NULL) {
193 if ((pt->name = strdup(arcn->name)) != NULL) {
194 pt->dev = arcn->sb.st_dev;
195 pt->ino = arcn->sb.st_ino;
196 pt->nlink = arcn->sb.st_nlink;
197 pt->fow = ltab[indx];
198 ltab[indx] = pt;
199 return(0);
200 }
57fed2af 201 free((char *)pt);
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202 }
203
204 paxwarn(1, "Hard link table out of memory");
205 return(-1);
206}
207
208/*
209 * purg_lnk
210 * remove reference for a file that we may have added to the data base as
211 * a potential source for hard links. We ended up not using the file, so
212 * we do not want to accidently point another file at it later on.
213 */
214
984263bc 215void
86a586bb 216purg_lnk(ARCHD *arcn)
984263bc 217{
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218 HRDLNK *pt;
219 HRDLNK **ppt;
220 u_int indx;
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221
222 if (ltab == NULL)
223 return;
224 /*
225 * do not bother to look if it could not be in the database
226 */
227 if ((arcn->sb.st_nlink <= 1) || (arcn->type == PAX_DIR) ||
228 (arcn->type == PAX_HLK) || (arcn->type == PAX_HRG))
229 return;
230
231 /*
232 * find the hash chain for this inode value, if empty return
233 */
234 indx = ((unsigned)arcn->sb.st_ino) % L_TAB_SZ;
235 if ((pt = ltab[indx]) == NULL)
236 return;
237
238 /*
239 * walk down the list looking for the inode/dev pair, unlink and
240 * free if found
241 */
242 ppt = &(ltab[indx]);
243 while (pt != NULL) {
244 if ((pt->ino == arcn->sb.st_ino) &&
245 (pt->dev == arcn->sb.st_dev))
246 break;
247 ppt = &(pt->fow);
248 pt = pt->fow;
249 }
250 if (pt == NULL)
251 return;
252
253 /*
254 * remove and free it
255 */
256 *ppt = pt->fow;
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257 free((char *)pt->name);
258 free((char *)pt);
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259}
260
261/*
262 * lnk_end()
263 * pull apart a existing link table so we can reuse it. We do this between
264 * read and write phases of append with update. (The format may have
265 * used the link table, and we need to start with a fresh table for the
266 * write phase
267 */
268
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269void
270lnk_end(void)
984263bc 271{
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272 int i;
273 HRDLNK *pt;
274 HRDLNK *ppt;
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275
276 if (ltab == NULL)
277 return;
278
279 for (i = 0; i < L_TAB_SZ; ++i) {
280 if (ltab[i] == NULL)
281 continue;
282 pt = ltab[i];
283 ltab[i] = NULL;
284
285 /*
286 * free up each entry on this chain
287 */
288 while (pt != NULL) {
289 ppt = pt;
290 pt = ppt->fow;
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291 free((char *)ppt->name);
292 free((char *)ppt);
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293 }
294 }
295 return;
296}
297
298/*
299 * modification time table routines
300 *
301 * The modification time table keeps track of last modification times for all
302 * files stored in an archive during a write phase when -u is set. We only
303 * add a file to the archive if it is newer than a file with the same name
304 * already stored on the archive (if there is no other file with the same
305 * name on the archive it is added). This applies to writes and appends.
306 * An append with an -u must read the archive and store the modification time
307 * for every file on that archive before starting the write phase. It is clear
308 * that this is one HUGE database. To save memory space, the actual file names
309 * are stored in a scatch file and indexed by an in memory hash table. The
310 * hash table is indexed by hashing the file path. The nodes in the table store
311 * the length of the filename and the lseek offset within the scratch file
312 * where the actual name is stored. Since there are never any deletions to this
313 * table, fragmentation of the scratch file is never a issue. Lookups seem to
314 * not exhibit any locality at all (files in the database are rarely
315 * looked up more than once...). So caching is just a waste of memory. The
316 * only limitation is the amount of scatch file space available to store the
317 * path names.
318 */
319
320/*
321 * ftime_start()
322 * create the file time hash table and open for read/write the scratch
323 * file. (after created it is unlinked, so when we exit we leave
324 * no witnesses).
325 * Return:
326 * 0 if the table and file was created ok, -1 otherwise
327 */
328
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329int
330ftime_start(void)
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331{
332
333 if (ftab != NULL)
334 return(0);
335 if ((ftab = (FTM **)calloc(F_TAB_SZ, sizeof(FTM *))) == NULL) {
336 paxwarn(1, "Cannot allocate memory for file time table");
337 return(-1);
338 }
339
340 /*
341 * get random name and create temporary scratch file, unlink name
342 * so it will get removed on exit
343 */
344 memcpy(tempbase, _TFILE_BASE, sizeof(_TFILE_BASE));
345 if ((ffd = mkstemp(tempfile)) < 0) {
346 syswarn(1, errno, "Unable to create temporary file: %s",
347 tempfile);
348 return(-1);
349 }
57fed2af 350 unlink(tempfile);
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351
352 return(0);
353}
354
355/*
356 * chk_ftime()
357 * looks up entry in file time hash table. If not found, the file is
358 * added to the hash table and the file named stored in the scratch file.
359 * If a file with the same name is found, the file times are compared and
360 * the most recent file time is retained. If the new file was younger (or
361 * was not in the database) the new file is selected for storage.
362 * Return:
363 * 0 if file should be added to the archive, 1 if it should be skipped,
364 * -1 on error
365 */
366
984263bc 367int
86a586bb 368chk_ftime(ARCHD *arcn)
984263bc 369{
86a586bb
LF
370 FTM *pt;
371 int namelen;
372 u_int indx;
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373 char ckname[PAXPATHLEN+1];
374
375 /*
376 * no info, go ahead and add to archive
377 */
378 if (ftab == NULL)
379 return(0);
380
381 /*
382 * hash the pathname and look up in table
383 */
384 namelen = arcn->nlen;
385 indx = st_hash(arcn->name, namelen, F_TAB_SZ);
386 if ((pt = ftab[indx]) != NULL) {
387 /*
388 * the hash chain is not empty, walk down looking for match
389 * only read up the path names if the lengths match, speeds
390 * up the search a lot
391 */
392 while (pt != NULL) {
393 if (pt->namelen == namelen) {
394 /*
395 * potential match, have to read the name
396 * from the scratch file.
397 */
398 if (lseek(ffd,pt->seek,SEEK_SET) != pt->seek) {
399 syswarn(1, errno,
400 "Failed ftime table seek");
401 return(-1);
402 }
403 if (read(ffd, ckname, namelen) != namelen) {
404 syswarn(1, errno,
405 "Failed ftime table read");
406 return(-1);
407 }
408
409 /*
410 * if the names match, we are done
411 */
412 if (!strncmp(ckname, arcn->name, namelen))
413 break;
414 }
415
416 /*
417 * try the next entry on the chain
418 */
419 pt = pt->fow;
420 }
421
422 if (pt != NULL) {
423 /*
424 * found the file, compare the times, save the newer
425 */
426 if (arcn->sb.st_mtime > pt->mtime) {
427 /*
428 * file is newer
429 */
430 pt->mtime = arcn->sb.st_mtime;
431 return(0);
432 }
433 /*
434 * file is older
435 */
436 return(1);
437 }
438 }
439
440 /*
441 * not in table, add it
442 */
443 if ((pt = (FTM *)malloc(sizeof(FTM))) != NULL) {
444 /*
445 * add the name at the end of the scratch file, saving the
446 * offset. add the file to the head of the hash chain
447 */
448 if ((pt->seek = lseek(ffd, (off_t)0, SEEK_END)) >= 0) {
449 if (write(ffd, arcn->name, namelen) == namelen) {
450 pt->mtime = arcn->sb.st_mtime;
451 pt->namelen = namelen;
452 pt->fow = ftab[indx];
453 ftab[indx] = pt;
454 return(0);
455 }
456 syswarn(1, errno, "Failed write to file time table");
457 } else
458 syswarn(1, errno, "Failed seek on file time table");
459 } else
460 paxwarn(1, "File time table ran out of memory");
461
462 if (pt != NULL)
57fed2af 463 free((char *)pt);
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464 return(-1);
465}
466
467/*
468 * Interactive rename table routines
469 *
470 * The interactive rename table keeps track of the new names that the user
471 * assigns to files from tty input. Since this map is unique for each file
472 * we must store it in case there is a reference to the file later in archive
473 * (a link). Otherwise we will be unable to find the file we know was
474 * extracted. The remapping of these files is stored in a memory based hash
475 * table (it is assumed since input must come from /dev/tty, it is unlikely to
476 * be a very large table).
477 */
478
479/*
480 * name_start()
481 * create the interactive rename table
482 * Return:
483 * 0 if successful, -1 otherwise
484 */
485
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486int
487name_start(void)
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488{
489 if (ntab != NULL)
490 return(0);
491 if ((ntab = (NAMT **)calloc(N_TAB_SZ, sizeof(NAMT *))) == NULL) {
492 paxwarn(1, "Cannot allocate memory for interactive rename table");
493 return(-1);
494 }
495 return(0);
496}
497
498/*
499 * add_name()
500 * add the new name to old name mapping just created by the user.
501 * If an old name mapping is found (there may be duplicate names on an
502 * archive) only the most recent is kept.
503 * Return:
504 * 0 if added, -1 otherwise
505 */
506
984263bc 507int
86a586bb 508add_name(char *oname, int onamelen, char *nname)
984263bc 509{
86a586bb
LF
510 NAMT *pt;
511 u_int indx;
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512
513 if (ntab == NULL) {
514 /*
515 * should never happen
516 */
517 paxwarn(0, "No interactive rename table, links may fail\n");
518 return(0);
519 }
520
521 /*
522 * look to see if we have already mapped this file, if so we
523 * will update it
524 */
525 indx = st_hash(oname, onamelen, N_TAB_SZ);
526 if ((pt = ntab[indx]) != NULL) {
527 /*
528 * look down the has chain for the file
529 */
530 while ((pt != NULL) && (strcmp(oname, pt->oname) != 0))
531 pt = pt->fow;
532
533 if (pt != NULL) {
534 /*
535 * found an old mapping, replace it with the new one
536 * the user just input (if it is different)
537 */
538 if (strcmp(nname, pt->nname) == 0)
539 return(0);
540
57fed2af 541 free((char *)pt->nname);
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542 if ((pt->nname = strdup(nname)) == NULL) {
543 paxwarn(1, "Cannot update rename table");
544 return(-1);
545 }
546 return(0);
547 }
548 }
549
550 /*
551 * this is a new mapping, add it to the table
552 */
553 if ((pt = (NAMT *)malloc(sizeof(NAMT))) != NULL) {
554 if ((pt->oname = strdup(oname)) != NULL) {
555 if ((pt->nname = strdup(nname)) != NULL) {
556 pt->fow = ntab[indx];
557 ntab[indx] = pt;
558 return(0);
559 }
57fed2af 560 free((char *)pt->oname);
984263bc 561 }
57fed2af 562 free((char *)pt);
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563 }
564 paxwarn(1, "Interactive rename table out of memory");
565 return(-1);
566}
567
568/*
569 * sub_name()
570 * look up a link name to see if it points at a file that has been
571 * remapped by the user. If found, the link is adjusted to contain the
572 * new name (oname is the link to name)
573 */
574
984263bc 575void
86a586bb 576sub_name(char *oname, int *onamelen, size_t onamesize)
984263bc 577{
86a586bb
LF
578 NAMT *pt;
579 u_int indx;
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580
581 if (ntab == NULL)
582 return;
583 /*
584 * look the name up in the hash table
585 */
586 indx = st_hash(oname, *onamelen, N_TAB_SZ);
587 if ((pt = ntab[indx]) == NULL)
588 return;
589
590 while (pt != NULL) {
591 /*
592 * walk down the hash chain looking for a match
593 */
594 if (strcmp(oname, pt->oname) == 0) {
595 /*
596 * found it, replace it with the new name
597 * and return (we know that oname has enough space)
598 */
599 *onamelen = l_strncpy(oname, pt->nname, onamesize - 1);
600 oname[*onamelen] = '\0';
601 return;
602 }
603 pt = pt->fow;
604 }
605
606 /*
607 * no match, just return
608 */
609 return;
610}
611
612/*
613 * device/inode mapping table routines
614 * (used with formats that store device and inodes fields)
615 *
616 * device/inode mapping tables remap the device field in a archive header. The
617 * device/inode fields are used to determine when files are hard links to each
618 * other. However these values have very little meaning outside of that. This
619 * database is used to solve one of two different problems.
620 *
621 * 1) when files are appended to an archive, while the new files may have hard
622 * links to each other, you cannot determine if they have hard links to any
623 * file already stored on the archive from a prior run of pax. We must assume
624 * that these inode/device pairs are unique only within a SINGLE run of pax
625 * (which adds a set of files to an archive). So we have to make sure the
626 * inode/dev pairs we add each time are always unique. We do this by observing
627 * while the inode field is very dense, the use of the dev field is fairly
628 * sparse. Within each run of pax, we remap any device number of a new archive
629 * member that has a device number used in a prior run and already stored in a
630 * file on the archive. During the read phase of the append, we store the
631 * device numbers used and mark them to not be used by any file during the
632 * write phase. If during write we go to use one of those old device numbers,
633 * we remap it to a new value.
634 *
635 * 2) Often the fields in the archive header used to store these values are
636 * too small to store the entire value. The result is an inode or device value
637 * which can be truncated. This really can foul up an archive. With truncation
638 * we end up creating links between files that are really not links (after
639 * truncation the inodes are the same value). We address that by detecting
640 * truncation and forcing a remap of the device field to split truncated
641 * inodes away from each other. Each truncation creates a pattern of bits that
642 * are removed. We use this pattern of truncated bits to partition the inodes
643 * on a single device to many different devices (each one represented by the
644 * truncated bit pattern). All inodes on the same device that have the same
645 * truncation pattern are mapped to the same new device. Two inodes that
646 * truncate to the same value clearly will always have different truncation
647 * bit patterns, so they will be split from away each other. When we spot
648 * device truncation we remap the device number to a non truncated value.
649 * (for more info see table.h for the data structures involved).
650 */
651
652/*
653 * dev_start()
654 * create the device mapping table
655 * Return:
656 * 0 if successful, -1 otherwise
657 */
658
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659int
660dev_start(void)
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661{
662 if (dtab != NULL)
663 return(0);
664 if ((dtab = (DEVT **)calloc(D_TAB_SZ, sizeof(DEVT *))) == NULL) {
665 paxwarn(1, "Cannot allocate memory for device mapping table");
666 return(-1);
667 }
668 return(0);
669}
670
671/*
672 * add_dev()
673 * add a device number to the table. this will force the device to be
674 * remapped to a new value if it be used during a write phase. This
675 * function is called during the read phase of an append to prohibit the
676 * use of any device number already in the archive.
677 * Return:
678 * 0 if added ok, -1 otherwise
679 */
680
984263bc 681int
86a586bb 682add_dev(ARCHD *arcn)
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MD
683{
684 if (chk_dev(arcn->sb.st_dev, 1) == NULL)
685 return(-1);
686 return(0);
687}
688
689/*
690 * chk_dev()
691 * check for a device value in the device table. If not found and the add
692 * flag is set, it is added. This does NOT assign any mapping values, just
693 * adds the device number as one that need to be remapped. If this device
694 * is already mapped, just return with a pointer to that entry.
695 * Return:
696 * pointer to the entry for this device in the device map table. Null
697 * if the add flag is not set and the device is not in the table (it is
698 * not been seen yet). If add is set and the device cannot be added, null
699 * is returned (indicates an error).
700 */
701
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702static DEVT *
703chk_dev(dev_t dev, int add)
984263bc 704{
86a586bb
LF
705 DEVT *pt;
706 u_int indx;
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707
708 if (dtab == NULL)
709 return(NULL);
710 /*
711 * look to see if this device is already in the table
712 */
713 indx = ((unsigned)dev) % D_TAB_SZ;
714 if ((pt = dtab[indx]) != NULL) {
715 while ((pt != NULL) && (pt->dev != dev))
716 pt = pt->fow;
717
718 /*
719 * found it, return a pointer to it
720 */
721 if (pt != NULL)
722 return(pt);
723 }
724
725 /*
726 * not in table, we add it only if told to as this may just be a check
727 * to see if a device number is being used.
728 */
729 if (add == 0)
730 return(NULL);
731
732 /*
733 * allocate a node for this device and add it to the front of the hash
734 * chain. Note we do not assign remaps values here, so the pt->list
735 * list must be NULL.
736 */
737 if ((pt = (DEVT *)malloc(sizeof(DEVT))) == NULL) {
738 paxwarn(1, "Device map table out of memory");
739 return(NULL);
740 }
741 pt->dev = dev;
742 pt->list = NULL;
743 pt->fow = dtab[indx];
744 dtab[indx] = pt;
745 return(pt);
746}
747/*
748 * map_dev()
749 * given an inode and device storage mask (the mask has a 1 for each bit
750 * the archive format is able to store in a header), we check for inode
751 * and device truncation and remap the device as required. Device mapping
752 * can also occur when during the read phase of append a device number was
753 * seen (and was marked as do not use during the write phase). WE ASSUME
754 * that unsigned longs are the same size or bigger than the fields used
755 * for ino_t and dev_t. If not the types will have to be changed.
756 * Return:
757 * 0 if all ok, -1 otherwise.
758 */
759
984263bc 760int
86a586bb 761map_dev(ARCHD *arcn, u_long dev_mask, u_long ino_mask)
984263bc 762{
86a586bb
LF
763 DEVT *pt;
764 DLIST *dpt;
984263bc
MD
765 static dev_t lastdev = 0; /* next device number to try */
766 int trc_ino = 0;
767 int trc_dev = 0;
768 ino_t trunc_bits = 0;
769 ino_t nino;
770
771 if (dtab == NULL)
772 return(0);
773 /*
774 * check for device and inode truncation, and extract the truncated
775 * bit pattern.
776 */
777 if ((arcn->sb.st_dev & (dev_t)dev_mask) != arcn->sb.st_dev)
778 ++trc_dev;
779 if ((nino = arcn->sb.st_ino & (ino_t)ino_mask) != arcn->sb.st_ino) {
780 ++trc_ino;
781 trunc_bits = arcn->sb.st_ino & (ino_t)(~ino_mask);
782 }
783
784 /*
785 * see if this device is already being mapped, look up the device
786 * then find the truncation bit pattern which applies
787 */
788 if ((pt = chk_dev(arcn->sb.st_dev, 0)) != NULL) {
789 /*
790 * this device is already marked to be remapped
791 */
792 for (dpt = pt->list; dpt != NULL; dpt = dpt->fow)
793 if (dpt->trunc_bits == trunc_bits)
794 break;
795
796 if (dpt != NULL) {
797 /*
798 * we are being remapped for this device and pattern
799 * change the device number to be stored and return
800 */
801 arcn->sb.st_dev = dpt->dev;
802 arcn->sb.st_ino = nino;
803 return(0);
804 }
805 } else {
806 /*
807 * this device is not being remapped YET. if we do not have any
808 * form of truncation, we do not need a remap
809 */
810 if (!trc_ino && !trc_dev)
811 return(0);
812
813 /*
814 * we have truncation, have to add this as a device to remap
815 */
816 if ((pt = chk_dev(arcn->sb.st_dev, 1)) == NULL)
817 goto bad;
818
819 /*
820 * if we just have a truncated inode, we have to make sure that
821 * all future inodes that do not truncate (they have the
822 * truncation pattern of all 0's) continue to map to the same
823 * device number. We probably have already written inodes with
824 * this device number to the archive with the truncation
825 * pattern of all 0's. So we add the mapping for all 0's to the
826 * same device number.
827 */
828 if (!trc_dev && (trunc_bits != 0)) {
829 if ((dpt = (DLIST *)malloc(sizeof(DLIST))) == NULL)
830 goto bad;
831 dpt->trunc_bits = 0;
832 dpt->dev = arcn->sb.st_dev;
833 dpt->fow = pt->list;
834 pt->list = dpt;
835 }
836 }
837
838 /*
839 * look for a device number not being used. We must watch for wrap
840 * around on lastdev (so we do not get stuck looking forever!)
841 */
842 while (++lastdev > 0) {
843 if (chk_dev(lastdev, 0) != NULL)
844 continue;
845 /*
846 * found an unused value. If we have reached truncation point
847 * for this format we are hosed, so we give up. Otherwise we
848 * mark it as being used.
849 */
850 if (((lastdev & ((dev_t)dev_mask)) != lastdev) ||
851 (chk_dev(lastdev, 1) == NULL))
852 goto bad;
853 break;
854 }
855
856 if ((lastdev <= 0) || ((dpt = (DLIST *)malloc(sizeof(DLIST))) == NULL))
857 goto bad;
858
859 /*
860 * got a new device number, store it under this truncation pattern.
861 * change the device number this file is being stored with.
862 */
863 dpt->trunc_bits = trunc_bits;
864 dpt->dev = lastdev;
865 dpt->fow = pt->list;
866 pt->list = dpt;
867 arcn->sb.st_dev = lastdev;
868 arcn->sb.st_ino = nino;
869 return(0);
870
871 bad:
872 paxwarn(1, "Unable to fix truncated inode/device field when storing %s",
873 arcn->name);
874 paxwarn(0, "Archive may create improper hard links when extracted");
875 return(0);
876}
877
878/*
879 * directory access/mod time reset table routines (for directories READ by pax)
880 *
881 * The pax -t flag requires that access times of archive files to be the same
882 * before being read by pax. For regular files, access time is restored after
883 * the file has been copied. This database provides the same functionality for
884 * directories read during file tree traversal. Restoring directory access time
885 * is more complex than files since directories may be read several times until
886 * all the descendants in their subtree are visited by fts. Directory access
887 * and modification times are stored during the fts pre-order visit (done
888 * before any descendants in the subtree is visited) and restored after the
889 * fts post-order visit (after all the descendants have been visited). In the
890 * case of premature exit from a subtree (like from the effects of -n), any
891 * directory entries left in this database are reset during final cleanup
892 * operations of pax. Entries are hashed by inode number for fast lookup.
893 */
894
895/*
896 * atdir_start()
897 * create the directory access time database for directories READ by pax.
898 * Return:
899 * 0 is created ok, -1 otherwise.
900 */
901
984263bc
MD
902int
903atdir_start(void)
984263bc
MD
904{
905 if (atab != NULL)
906 return(0);
907 if ((atab = (ATDIR **)calloc(A_TAB_SZ, sizeof(ATDIR *))) == NULL) {
908 paxwarn(1,"Cannot allocate space for directory access time table");
909 return(-1);
910 }
911 return(0);
912}
913
914
915/*
916 * atdir_end()
917 * walk through the directory access time table and reset the access time
918 * of any directory who still has an entry left in the database. These
919 * entries are for directories READ by pax
920 */
921
984263bc
MD
922void
923atdir_end(void)
984263bc 924{
86a586bb
LF
925 ATDIR *pt;
926 int i;
984263bc
MD
927
928 if (atab == NULL)
929 return;
930 /*
931 * for each non-empty hash table entry reset all the directories
932 * chained there.
933 */
934 for (i = 0; i < A_TAB_SZ; ++i) {
935 if ((pt = atab[i]) == NULL)
936 continue;
937 /*
938 * remember to force the times, set_ftime() looks at pmtime
939 * and patime, which only applies to things CREATED by pax,
940 * not read by pax. Read time reset is controlled by -t.
941 */
942 for (; pt != NULL; pt = pt->fow)
943 set_ftime(pt->name, pt->mtime, pt->atime, 1);
944 }
945}
946
947/*
948 * add_atdir()
949 * add a directory to the directory access time table. Table is hashed
950 * and chained by inode number. This is for directories READ by pax
951 */
952
984263bc
MD
953void
954add_atdir(char *fname, dev_t dev, ino_t ino, time_t mtime, time_t atime)
984263bc 955{
86a586bb
LF
956 ATDIR *pt;
957 u_int indx;
984263bc
MD
958
959 if (atab == NULL)
960 return;
961
962 /*
963 * make sure this directory is not already in the table, if so just
964 * return (the older entry always has the correct time). The only
965 * way this will happen is when the same subtree can be traversed by
966 * different args to pax and the -n option is aborting fts out of a
967 * subtree before all the post-order visits have been made).
968 */
969 indx = ((unsigned)ino) % A_TAB_SZ;
970 if ((pt = atab[indx]) != NULL) {
971 while (pt != NULL) {
972 if ((pt->ino == ino) && (pt->dev == dev))
973 break;
974 pt = pt->fow;
975 }
976
977 /*
978 * oops, already there. Leave it alone.
979 */
980 if (pt != NULL)
981 return;
982 }
983
984 /*
985 * add it to the front of the hash chain
986 */
987 if ((pt = (ATDIR *)malloc(sizeof(ATDIR))) != NULL) {
988 if ((pt->name = strdup(fname)) != NULL) {
989 pt->dev = dev;
990 pt->ino = ino;
991 pt->mtime = mtime;
992 pt->atime = atime;
993 pt->fow = atab[indx];
994 atab[indx] = pt;
995 return;
996 }
57fed2af 997 free((char *)pt);
984263bc
MD
998 }
999
1000 paxwarn(1, "Directory access time reset table ran out of memory");
1001 return;
1002}
1003
1004/*
1005 * get_atdir()
1006 * look up a directory by inode and device number to obtain the access
1007 * and modification time you want to set to. If found, the modification
1008 * and access time parameters are set and the entry is removed from the
1009 * table (as it is no longer needed). These are for directories READ by
1010 * pax
1011 * Return:
1012 * 0 if found, -1 if not found.
1013 */
1014
984263bc
MD
1015int
1016get_atdir(dev_t dev, ino_t ino, time_t *mtime, time_t *atime)
984263bc 1017{
86a586bb
LF
1018 ATDIR *pt;
1019 ATDIR **ppt;
1020 u_int indx;
984263bc
MD
1021
1022 if (atab == NULL)
1023 return(-1);
1024 /*
1025 * hash by inode and search the chain for an inode and device match
1026 */
1027 indx = ((unsigned)ino) % A_TAB_SZ;
1028 if ((pt = atab[indx]) == NULL)
1029 return(-1);
1030
1031 ppt = &(atab[indx]);
1032 while (pt != NULL) {
1033 if ((pt->ino == ino) && (pt->dev == dev))
1034 break;
1035 /*
1036 * no match, go to next one
1037 */
1038 ppt = &(pt->fow);
1039 pt = pt->fow;
1040 }
1041
1042 /*
1043 * return if we did not find it.
1044 */
1045 if (pt == NULL)
1046 return(-1);
1047
1048 /*
1049 * found it. return the times and remove the entry from the table.
1050 */
1051 *ppt = pt->fow;
1052 *mtime = pt->mtime;
1053 *atime = pt->atime;
57fed2af
EN
1054 free((char *)pt->name);
1055 free((char *)pt);
984263bc
MD
1056 return(0);
1057}
1058
1059/*
1060 * directory access mode and time storage routines (for directories CREATED
1061 * by pax).
1062 *
1063 * Pax requires that extracted directories, by default, have their access/mod
1064 * times and permissions set to the values specified in the archive. During the
1065 * actions of extracting (and creating the destination subtree during -rw copy)
1066 * directories extracted may be modified after being created. Even worse is
1067 * that these directories may have been created with file permissions which
1068 * prohibits any descendants of these directories from being extracted. When
1069 * directories are created by pax, access rights may be added to permit the
1070 * creation of files in their subtree. Every time pax creates a directory, the
1071 * times and file permissions specified by the archive are stored. After all
1072 * files have been extracted (or copied), these directories have their times
1073 * and file modes reset to the stored values. The directory info is restored in
1074 * reverse order as entries were added to the data file from root to leaf. To
1075 * restore atime properly, we must go backwards. The data file consists of
1076 * records with two parts, the file name followed by a DIRDATA trailer. The
1077 * fixed sized trailer contains the size of the name plus the off_t location in
1078 * the file. To restore we work backwards through the file reading the trailer
1079 * then the file name.
1080 */
1081
1082/*
1083 * dir_start()
1084 * set up the directory time and file mode storage for directories CREATED
1085 * by pax.
1086 * Return:
1087 * 0 if ok, -1 otherwise
1088 */
1089
984263bc
MD
1090int
1091dir_start(void)
984263bc
MD
1092{
1093
1094 if (dirfd != -1)
1095 return(0);
1096
1097 /*
1098 * unlink the file so it goes away at termination by itself
1099 */
1100 memcpy(tempbase, _TFILE_BASE, sizeof(_TFILE_BASE));
1101 if ((dirfd = mkstemp(tempfile)) >= 0) {
57fed2af 1102 unlink(tempfile);
984263bc
MD
1103 return(0);
1104 }
1105 paxwarn(1, "Unable to create temporary file for directory times: %s",
1106 tempfile);
1107 return(-1);
1108}
1109
1110/*
1111 * add_dir()
1112 * add the mode and times for a newly CREATED directory
1113 * name is name of the directory, psb the stat buffer with the data in it,
1114 * frc_mode is a flag that says whether to force the setting of the mode
1115 * (ignoring the user set values for preserving file mode). Frc_mode is
1116 * for the case where we created a file and found that the resulting
1117 * directory was not writeable and the user asked for file modes to NOT
1118 * be preserved. (we have to preserve what was created by default, so we
1119 * have to force the setting at the end. this is stated explicitly in the
1120 * pax spec)
1121 */
1122
984263bc
MD
1123void
1124add_dir(char *name, int nlen, struct stat *psb, int frc_mode)
984263bc
MD
1125{
1126 DIRDATA dblk;
1127
1128 if (dirfd < 0)
1129 return;
1130
1131 /*
1132 * get current position (where file name will start) so we can store it
1133 * in the trailer
1134 */
1135 if ((dblk.npos = lseek(dirfd, 0L, SEEK_CUR)) < 0) {
1136 paxwarn(1,"Unable to store mode and times for directory: %s",name);
1137 return;
1138 }
1139
1140 /*
1141 * write the file name followed by the trailer
1142 */
1143 dblk.nlen = nlen + 1;
1144 dblk.mode = psb->st_mode & 0xffff;
1145 dblk.mtime = psb->st_mtime;
1146 dblk.atime = psb->st_atime;
1147 dblk.frc_mode = frc_mode;
1148 if ((write(dirfd, name, dblk.nlen) == dblk.nlen) &&
1149 (write(dirfd, (char *)&dblk, sizeof(dblk)) == sizeof(dblk))) {
1150 ++dircnt;
1151 return;
1152 }
1153
1154 paxwarn(1,"Unable to store mode and times for created directory: %s",name);
1155 return;
1156}
1157
1158/*
1159 * proc_dir()
1160 * process all file modes and times stored for directories CREATED
1161 * by pax
1162 */
1163
984263bc
MD
1164void
1165proc_dir(void)
984263bc
MD
1166{
1167 char name[PAXPATHLEN+1];
1168 DIRDATA dblk;
1169 u_long cnt;
1170
1171 if (dirfd < 0)
1172 return;
1173 /*
1174 * read backwards through the file and process each directory
1175 */
1176 for (cnt = 0; cnt < dircnt; ++cnt) {
1177 /*
1178 * read the trailer, then the file name, if this fails
1179 * just give up.
1180 */
1181 if (lseek(dirfd, -((off_t)sizeof(dblk)), SEEK_CUR) < 0)
1182 break;
1183 if (read(dirfd,(char *)&dblk, sizeof(dblk)) != sizeof(dblk))
1184 break;
1185 if (lseek(dirfd, dblk.npos, SEEK_SET) < 0)
1186 break;
1187 if (read(dirfd, name, dblk.nlen) != dblk.nlen)
1188 break;
1189 if (lseek(dirfd, dblk.npos, SEEK_SET) < 0)
1190 break;
1191
1192 /*
1193 * frc_mode set, make sure we set the file modes even if
1194 * the user didn't ask for it (see file_subs.c for more info)
1195 */
1196 if (pmode || dblk.frc_mode)
1197 set_pmode(name, dblk.mode);
1198 if (patime || pmtime)
1199 set_ftime(name, dblk.mtime, dblk.atime, 0);
1200 }
1201
57fed2af 1202 close(dirfd);
984263bc
MD
1203 dirfd = -1;
1204 if (cnt != dircnt)
1205 paxwarn(1,"Unable to set mode and times for created directories");
1206 return;
1207}
1208
1209/*
1210 * database independent routines
1211 */
1212
1213/*
1214 * st_hash()
1215 * hashes filenames to a u_int for hashing into a table. Looks at the tail
1216 * end of file, as this provides far better distribution than any other
1217 * part of the name. For performance reasons we only care about the last
1218 * MAXKEYLEN chars (should be at LEAST large enough to pick off the file
1219 * name). Was tested on 500,000 name file tree traversal from the root
1220 * and gave almost a perfectly uniform distribution of keys when used with
1221 * prime sized tables (MAXKEYLEN was 128 in test). Hashes (sizeof int)
1222 * chars at a time and pads with 0 for last addition.
1223 * Return:
1224 * the hash value of the string MOD (%) the table size.
1225 */
1226
984263bc
MD
1227u_int
1228st_hash(char *name, int len, int tabsz)
984263bc 1229{
86a586bb
LF
1230 char *pt;
1231 char *dest;
1232 char *end;
1233 int i;
1234 u_int key = 0;
1235 int steps;
1236 int res;
984263bc
MD
1237 u_int val;
1238
1239 /*
1240 * only look at the tail up to MAXKEYLEN, we do not need to waste
1241 * time here (remember these are pathnames, the tail is what will
1242 * spread out the keys)
1243 */
1244 if (len > MAXKEYLEN) {
1245 pt = &(name[len - MAXKEYLEN]);
1246 len = MAXKEYLEN;
1247 } else
1248 pt = name;
1249
1250 /*
1251 * calculate the number of u_int size steps in the string and if
1252 * there is a runt to deal with
1253 */
1254 steps = len/sizeof(u_int);
1255 res = len % sizeof(u_int);
1256
1257 /*
1258 * add up the value of the string in unsigned integer sized pieces
1259 * too bad we cannot have unsigned int aligned strings, then we
1260 * could avoid the expensive copy.
1261 */
1262 for (i = 0; i < steps; ++i) {
1263 end = pt + sizeof(u_int);
1264 dest = (char *)&val;
1265 while (pt < end)
1266 *dest++ = *pt++;
1267 key += val;
1268 }
1269
1270 /*
1271 * add in the runt padded with zero to the right
1272 */
1273 if (res) {
1274 val = 0;
1275 end = pt + res;
1276 dest = (char *)&val;
1277 while (pt < end)
1278 *dest++ = *pt++;
1279 key += val;
1280 }
1281
1282 /*
1283 * return the result mod the table size
1284 */
1285 return(key % tabsz);
1286}