2 * Copyright (c) 1992 Keith Muller.
3 * Copyright (c) 1992, 1993
4 * The Regents of the University of California. All rights reserved.
6 * This code is derived from software contributed to Berkeley by
7 * Keith Muller of the University of California, San Diego.
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
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.
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
40 static char sccsid[] = "@(#)tables.c 8.1 (Berkeley) 5/31/93";
42 static const char rcsid[] =
43 "$FreeBSD: src/bin/pax/tables.c,v 1.13.2.1 2001/08/01 05:03:12 obrien Exp $";
46 #include <sys/types.h>
49 #include <sys/fcntl.h>
60 * Routines for controlling the contents of all the different databases pax
61 * keeps. Tables are dynamically created only when they are needed. The
62 * goal was speed and the ability to work with HUGE archives. The databases
63 * were kept simple, but do have complex rules for when the contents change.
64 * As of this writing, the POSIX library functions were more complex than
65 * needed for this application (pax databases have very short lifetimes and
66 * do not survive after pax is finished). Pax is required to handle very
67 * large archives. These database routines carefully combine memory usage and
68 * temporary file storage in ways which will not significantly impact runtime
69 * performance while allowing the largest possible archives to be handled.
70 * Trying to force the fit to the POSIX databases routines was not considered
74 static HRDLNK **ltab = NULL; /* hard link table for detecting hard links */
75 static FTM **ftab = NULL; /* file time table for updating arch */
76 static NAMT **ntab = NULL; /* interactive rename storage table */
77 static DEVT **dtab = NULL; /* device/inode mapping tables */
78 static ATDIR **atab = NULL; /* file tree directory time reset table */
79 static int dirfd = -1; /* storage for setting created dir time/mode */
80 static u_long dircnt; /* entries in dir time/mode storage */
81 static int ffd = -1; /* tmp file for file time table name storage */
83 static DEVT *chk_dev __P((dev_t, int));
86 * hard link table routines
88 * The hard link table tries to detect hard links to files using the device and
89 * inode values. We do this when writing an archive, so we can tell the format
90 * write routine that this file is a hard link to another file. The format
91 * write routine then can store this file in whatever way it wants (as a hard
92 * link if the format supports that like tar, or ignore this info like cpio).
93 * (Actually a field in the format driver table tells us if the format wants
94 * hard link info. if not, we do not waste time looking for them). We also use
95 * the same table when reading an archive. In that situation, this table is
96 * used by the format read routine to detect hard links from stored dev and
97 * inode numbers (like cpio). This will allow pax to create a link when one
98 * can be detected by the archive format.
103 * Creates the hard link table.
105 * 0 if created, -1 if failure
118 if ((ltab = (HRDLNK **)calloc(L_TAB_SZ, sizeof(HRDLNK *))) == NULL) {
119 paxwarn(1, "Cannot allocate memory for hard link table");
127 * Looks up entry in hard link hash table. If found, it copies the name
128 * of the file it is linked to (we already saw that file) into ln_name.
129 * lnkcnt is decremented and if goes to 1 the node is deleted from the
130 * database. (We have seen all the links to this file). If not found,
131 * we add the file to the database if it has the potential for having
132 * hard links to other files we may process (it has a link count > 1)
134 * if found returns 1; if not found returns 0; -1 on error
139 chk_lnk(register ARCHD *arcn)
143 register ARCHD *arcn;
147 register HRDLNK **ppt;
153 * ignore those nodes that cannot have hard links
155 if ((arcn->type == PAX_DIR) || (arcn->sb.st_nlink <= 1))
159 * hash inode number and look for this file
161 indx = ((unsigned)arcn->sb.st_ino) % L_TAB_SZ;
162 if ((pt = ltab[indx]) != NULL) {
164 * it's hash chain in not empty, walk down looking for it
168 if ((pt->ino == arcn->sb.st_ino) &&
169 (pt->dev == arcn->sb.st_dev))
177 * found a link. set the node type and copy in the
178 * name of the file it is to link to. we need to
179 * handle hardlinks to regular files differently than
182 arcn->ln_nlen = l_strncpy(arcn->ln_name, pt->name,
183 sizeof(arcn->ln_name) - 1);
184 arcn->ln_name[arcn->ln_nlen] = '\0';
185 if (arcn->type == PAX_REG)
186 arcn->type = PAX_HRG;
188 arcn->type = PAX_HLK;
191 * if we have found all the links to this file, remove
192 * it from the database
194 if (--pt->nlink <= 1) {
196 (void)free((char *)pt->name);
197 (void)free((char *)pt);
204 * we never saw this file before. It has links so we add it to the
205 * front of this hash chain
207 if ((pt = (HRDLNK *)malloc(sizeof(HRDLNK))) != NULL) {
208 if ((pt->name = strdup(arcn->name)) != NULL) {
209 pt->dev = arcn->sb.st_dev;
210 pt->ino = arcn->sb.st_ino;
211 pt->nlink = arcn->sb.st_nlink;
212 pt->fow = ltab[indx];
216 (void)free((char *)pt);
219 paxwarn(1, "Hard link table out of memory");
225 * remove reference for a file that we may have added to the data base as
226 * a potential source for hard links. We ended up not using the file, so
227 * we do not want to accidently point another file at it later on.
232 purg_lnk(register ARCHD *arcn)
236 register ARCHD *arcn;
240 register HRDLNK **ppt;
246 * do not bother to look if it could not be in the database
248 if ((arcn->sb.st_nlink <= 1) || (arcn->type == PAX_DIR) ||
249 (arcn->type == PAX_HLK) || (arcn->type == PAX_HRG))
253 * find the hash chain for this inode value, if empty return
255 indx = ((unsigned)arcn->sb.st_ino) % L_TAB_SZ;
256 if ((pt = ltab[indx]) == NULL)
260 * walk down the list looking for the inode/dev pair, unlink and
265 if ((pt->ino == arcn->sb.st_ino) &&
266 (pt->dev == arcn->sb.st_dev))
278 (void)free((char *)pt->name);
279 (void)free((char *)pt);
284 * pull apart a existing link table so we can reuse it. We do this between
285 * read and write phases of append with update. (The format may have
286 * used the link table, and we need to start with a fresh table for the
300 register HRDLNK *ppt;
305 for (i = 0; i < L_TAB_SZ; ++i) {
312 * free up each entry on this chain
317 (void)free((char *)ppt->name);
318 (void)free((char *)ppt);
325 * modification time table routines
327 * The modification time table keeps track of last modification times for all
328 * files stored in an archive during a write phase when -u is set. We only
329 * add a file to the archive if it is newer than a file with the same name
330 * already stored on the archive (if there is no other file with the same
331 * name on the archive it is added). This applies to writes and appends.
332 * An append with an -u must read the archive and store the modification time
333 * for every file on that archive before starting the write phase. It is clear
334 * that this is one HUGE database. To save memory space, the actual file names
335 * are stored in a scatch file and indexed by an in memory hash table. The
336 * hash table is indexed by hashing the file path. The nodes in the table store
337 * the length of the filename and the lseek offset within the scratch file
338 * where the actual name is stored. Since there are never any deletions to this
339 * table, fragmentation of the scratch file is never a issue. Lookups seem to
340 * not exhibit any locality at all (files in the database are rarely
341 * looked up more than once...). So caching is just a waste of memory. The
342 * only limitation is the amount of scatch file space available to store the
348 * create the file time hash table and open for read/write the scratch
349 * file. (after created it is unlinked, so when we exit we leave
352 * 0 if the table and file was created ok, -1 otherwise
366 if ((ftab = (FTM **)calloc(F_TAB_SZ, sizeof(FTM *))) == NULL) {
367 paxwarn(1, "Cannot allocate memory for file time table");
372 * get random name and create temporary scratch file, unlink name
373 * so it will get removed on exit
375 memcpy(tempbase, _TFILE_BASE, sizeof(_TFILE_BASE));
376 if ((ffd = mkstemp(tempfile)) < 0) {
377 syswarn(1, errno, "Unable to create temporary file: %s",
381 (void)unlink(tempfile);
388 * looks up entry in file time hash table. If not found, the file is
389 * added to the hash table and the file named stored in the scratch file.
390 * If a file with the same name is found, the file times are compared and
391 * the most recent file time is retained. If the new file was younger (or
392 * was not in the database) the new file is selected for storage.
394 * 0 if file should be added to the archive, 1 if it should be skipped,
400 chk_ftime(register ARCHD *arcn)
404 register ARCHD *arcn;
408 register int namelen;
410 char ckname[PAXPATHLEN+1];
413 * no info, go ahead and add to archive
419 * hash the pathname and look up in table
421 namelen = arcn->nlen;
422 indx = st_hash(arcn->name, namelen, F_TAB_SZ);
423 if ((pt = ftab[indx]) != NULL) {
425 * the hash chain is not empty, walk down looking for match
426 * only read up the path names if the lengths match, speeds
427 * up the search a lot
430 if (pt->namelen == namelen) {
432 * potential match, have to read the name
433 * from the scratch file.
435 if (lseek(ffd,pt->seek,SEEK_SET) != pt->seek) {
437 "Failed ftime table seek");
440 if (read(ffd, ckname, namelen) != namelen) {
442 "Failed ftime table read");
447 * if the names match, we are done
449 if (!strncmp(ckname, arcn->name, namelen))
454 * try the next entry on the chain
461 * found the file, compare the times, save the newer
463 if (arcn->sb.st_mtime > pt->mtime) {
467 pt->mtime = arcn->sb.st_mtime;
478 * not in table, add it
480 if ((pt = (FTM *)malloc(sizeof(FTM))) != NULL) {
482 * add the name at the end of the scratch file, saving the
483 * offset. add the file to the head of the hash chain
485 if ((pt->seek = lseek(ffd, (off_t)0, SEEK_END)) >= 0) {
486 if (write(ffd, arcn->name, namelen) == namelen) {
487 pt->mtime = arcn->sb.st_mtime;
488 pt->namelen = namelen;
489 pt->fow = ftab[indx];
493 syswarn(1, errno, "Failed write to file time table");
495 syswarn(1, errno, "Failed seek on file time table");
497 paxwarn(1, "File time table ran out of memory");
500 (void)free((char *)pt);
505 * Interactive rename table routines
507 * The interactive rename table keeps track of the new names that the user
508 * assigns to files from tty input. Since this map is unique for each file
509 * we must store it in case there is a reference to the file later in archive
510 * (a link). Otherwise we will be unable to find the file we know was
511 * extracted. The remapping of these files is stored in a memory based hash
512 * table (it is assumed since input must come from /dev/tty, it is unlikely to
513 * be a very large table).
518 * create the interactive rename table
520 * 0 if successful, -1 otherwise
533 if ((ntab = (NAMT **)calloc(N_TAB_SZ, sizeof(NAMT *))) == NULL) {
534 paxwarn(1, "Cannot allocate memory for interactive rename table");
542 * add the new name to old name mapping just created by the user.
543 * If an old name mapping is found (there may be duplicate names on an
544 * archive) only the most recent is kept.
546 * 0 if added, -1 otherwise
551 add_name(register char *oname, int onamelen, char *nname)
554 add_name(oname, onamelen, nname)
555 register char *oname;
565 * should never happen
567 paxwarn(0, "No interactive rename table, links may fail\n");
572 * look to see if we have already mapped this file, if so we
575 indx = st_hash(oname, onamelen, N_TAB_SZ);
576 if ((pt = ntab[indx]) != NULL) {
578 * look down the has chain for the file
580 while ((pt != NULL) && (strcmp(oname, pt->oname) != 0))
585 * found an old mapping, replace it with the new one
586 * the user just input (if it is different)
588 if (strcmp(nname, pt->nname) == 0)
591 (void)free((char *)pt->nname);
592 if ((pt->nname = strdup(nname)) == NULL) {
593 paxwarn(1, "Cannot update rename table");
601 * this is a new mapping, add it to the table
603 if ((pt = (NAMT *)malloc(sizeof(NAMT))) != NULL) {
604 if ((pt->oname = strdup(oname)) != NULL) {
605 if ((pt->nname = strdup(nname)) != NULL) {
606 pt->fow = ntab[indx];
610 (void)free((char *)pt->oname);
612 (void)free((char *)pt);
614 paxwarn(1, "Interactive rename table out of memory");
620 * look up a link name to see if it points at a file that has been
621 * remapped by the user. If found, the link is adjusted to contain the
622 * new name (oname is the link to name)
627 sub_name(register char *oname, int *onamelen, size_t onamesize)
630 sub_name(oname, onamelen, onamesize)
631 register char *oname;
642 * look the name up in the hash table
644 indx = st_hash(oname, *onamelen, N_TAB_SZ);
645 if ((pt = ntab[indx]) == NULL)
650 * walk down the hash chain looking for a match
652 if (strcmp(oname, pt->oname) == 0) {
654 * found it, replace it with the new name
655 * and return (we know that oname has enough space)
657 *onamelen = l_strncpy(oname, pt->nname, onamesize - 1);
658 oname[*onamelen] = '\0';
665 * no match, just return
671 * device/inode mapping table routines
672 * (used with formats that store device and inodes fields)
674 * device/inode mapping tables remap the device field in a archive header. The
675 * device/inode fields are used to determine when files are hard links to each
676 * other. However these values have very little meaning outside of that. This
677 * database is used to solve one of two different problems.
679 * 1) when files are appended to an archive, while the new files may have hard
680 * links to each other, you cannot determine if they have hard links to any
681 * file already stored on the archive from a prior run of pax. We must assume
682 * that these inode/device pairs are unique only within a SINGLE run of pax
683 * (which adds a set of files to an archive). So we have to make sure the
684 * inode/dev pairs we add each time are always unique. We do this by observing
685 * while the inode field is very dense, the use of the dev field is fairly
686 * sparse. Within each run of pax, we remap any device number of a new archive
687 * member that has a device number used in a prior run and already stored in a
688 * file on the archive. During the read phase of the append, we store the
689 * device numbers used and mark them to not be used by any file during the
690 * write phase. If during write we go to use one of those old device numbers,
691 * we remap it to a new value.
693 * 2) Often the fields in the archive header used to store these values are
694 * too small to store the entire value. The result is an inode or device value
695 * which can be truncated. This really can foul up an archive. With truncation
696 * we end up creating links between files that are really not links (after
697 * truncation the inodes are the same value). We address that by detecting
698 * truncation and forcing a remap of the device field to split truncated
699 * inodes away from each other. Each truncation creates a pattern of bits that
700 * are removed. We use this pattern of truncated bits to partition the inodes
701 * on a single device to many different devices (each one represented by the
702 * truncated bit pattern). All inodes on the same device that have the same
703 * truncation pattern are mapped to the same new device. Two inodes that
704 * truncate to the same value clearly will always have different truncation
705 * bit patterns, so they will be split from away each other. When we spot
706 * device truncation we remap the device number to a non truncated value.
707 * (for more info see table.h for the data structures involved).
712 * create the device mapping table
714 * 0 if successful, -1 otherwise
727 if ((dtab = (DEVT **)calloc(D_TAB_SZ, sizeof(DEVT *))) == NULL) {
728 paxwarn(1, "Cannot allocate memory for device mapping table");
736 * add a device number to the table. this will force the device to be
737 * remapped to a new value if it be used during a write phase. This
738 * function is called during the read phase of an append to prohibit the
739 * use of any device number already in the archive.
741 * 0 if added ok, -1 otherwise
746 add_dev(register ARCHD *arcn)
750 register ARCHD *arcn;
753 if (chk_dev(arcn->sb.st_dev, 1) == NULL)
760 * check for a device value in the device table. If not found and the add
761 * flag is set, it is added. This does NOT assign any mapping values, just
762 * adds the device number as one that need to be remapped. If this device
763 * is already mapped, just return with a pointer to that entry.
765 * pointer to the entry for this device in the device map table. Null
766 * if the add flag is not set and the device is not in the table (it is
767 * not been seen yet). If add is set and the device cannot be added, null
768 * is returned (indicates an error).
773 chk_dev(dev_t dev, int add)
787 * look to see if this device is already in the table
789 indx = ((unsigned)dev) % D_TAB_SZ;
790 if ((pt = dtab[indx]) != NULL) {
791 while ((pt != NULL) && (pt->dev != dev))
795 * found it, return a pointer to it
802 * not in table, we add it only if told to as this may just be a check
803 * to see if a device number is being used.
809 * allocate a node for this device and add it to the front of the hash
810 * chain. Note we do not assign remaps values here, so the pt->list
813 if ((pt = (DEVT *)malloc(sizeof(DEVT))) == NULL) {
814 paxwarn(1, "Device map table out of memory");
819 pt->fow = dtab[indx];
825 * given an inode and device storage mask (the mask has a 1 for each bit
826 * the archive format is able to store in a header), we check for inode
827 * and device truncation and remap the device as required. Device mapping
828 * can also occur when during the read phase of append a device number was
829 * seen (and was marked as do not use during the write phase). WE ASSUME
830 * that unsigned longs are the same size or bigger than the fields used
831 * for ino_t and dev_t. If not the types will have to be changed.
833 * 0 if all ok, -1 otherwise.
838 map_dev(register ARCHD *arcn, u_long dev_mask, u_long ino_mask)
841 map_dev(arcn, dev_mask, ino_mask)
842 register ARCHD *arcn;
849 static dev_t lastdev = 0; /* next device number to try */
852 ino_t trunc_bits = 0;
858 * check for device and inode truncation, and extract the truncated
861 if ((arcn->sb.st_dev & (dev_t)dev_mask) != arcn->sb.st_dev)
863 if ((nino = arcn->sb.st_ino & (ino_t)ino_mask) != arcn->sb.st_ino) {
865 trunc_bits = arcn->sb.st_ino & (ino_t)(~ino_mask);
869 * see if this device is already being mapped, look up the device
870 * then find the truncation bit pattern which applies
872 if ((pt = chk_dev(arcn->sb.st_dev, 0)) != NULL) {
874 * this device is already marked to be remapped
876 for (dpt = pt->list; dpt != NULL; dpt = dpt->fow)
877 if (dpt->trunc_bits == trunc_bits)
882 * we are being remapped for this device and pattern
883 * change the device number to be stored and return
885 arcn->sb.st_dev = dpt->dev;
886 arcn->sb.st_ino = nino;
891 * this device is not being remapped YET. if we do not have any
892 * form of truncation, we do not need a remap
894 if (!trc_ino && !trc_dev)
898 * we have truncation, have to add this as a device to remap
900 if ((pt = chk_dev(arcn->sb.st_dev, 1)) == NULL)
904 * if we just have a truncated inode, we have to make sure that
905 * all future inodes that do not truncate (they have the
906 * truncation pattern of all 0's) continue to map to the same
907 * device number. We probably have already written inodes with
908 * this device number to the archive with the truncation
909 * pattern of all 0's. So we add the mapping for all 0's to the
910 * same device number.
912 if (!trc_dev && (trunc_bits != 0)) {
913 if ((dpt = (DLIST *)malloc(sizeof(DLIST))) == NULL)
916 dpt->dev = arcn->sb.st_dev;
923 * look for a device number not being used. We must watch for wrap
924 * around on lastdev (so we do not get stuck looking forever!)
926 while (++lastdev > 0) {
927 if (chk_dev(lastdev, 0) != NULL)
930 * found an unused value. If we have reached truncation point
931 * for this format we are hosed, so we give up. Otherwise we
932 * mark it as being used.
934 if (((lastdev & ((dev_t)dev_mask)) != lastdev) ||
935 (chk_dev(lastdev, 1) == NULL))
940 if ((lastdev <= 0) || ((dpt = (DLIST *)malloc(sizeof(DLIST))) == NULL))
944 * got a new device number, store it under this truncation pattern.
945 * change the device number this file is being stored with.
947 dpt->trunc_bits = trunc_bits;
951 arcn->sb.st_dev = lastdev;
952 arcn->sb.st_ino = nino;
956 paxwarn(1, "Unable to fix truncated inode/device field when storing %s",
958 paxwarn(0, "Archive may create improper hard links when extracted");
963 * directory access/mod time reset table routines (for directories READ by pax)
965 * The pax -t flag requires that access times of archive files to be the same
966 * before being read by pax. For regular files, access time is restored after
967 * the file has been copied. This database provides the same functionality for
968 * directories read during file tree traversal. Restoring directory access time
969 * is more complex than files since directories may be read several times until
970 * all the descendants in their subtree are visited by fts. Directory access
971 * and modification times are stored during the fts pre-order visit (done
972 * before any descendants in the subtree is visited) and restored after the
973 * fts post-order visit (after all the descendants have been visited). In the
974 * case of premature exit from a subtree (like from the effects of -n), any
975 * directory entries left in this database are reset during final cleanup
976 * operations of pax. Entries are hashed by inode number for fast lookup.
981 * create the directory access time database for directories READ by pax.
983 * 0 is created ok, -1 otherwise.
996 if ((atab = (ATDIR **)calloc(A_TAB_SZ, sizeof(ATDIR *))) == NULL) {
997 paxwarn(1,"Cannot allocate space for directory access time table");
1006 * walk through the directory access time table and reset the access time
1007 * of any directory who still has an entry left in the database. These
1008 * entries are for directories READ by pax
1025 * for each non-empty hash table entry reset all the directories
1028 for (i = 0; i < A_TAB_SZ; ++i) {
1029 if ((pt = atab[i]) == NULL)
1032 * remember to force the times, set_ftime() looks at pmtime
1033 * and patime, which only applies to things CREATED by pax,
1034 * not read by pax. Read time reset is controlled by -t.
1036 for (; pt != NULL; pt = pt->fow)
1037 set_ftime(pt->name, pt->mtime, pt->atime, 1);
1043 * add a directory to the directory access time table. Table is hashed
1044 * and chained by inode number. This is for directories READ by pax
1049 add_atdir(char *fname, dev_t dev, ino_t ino, time_t mtime, time_t atime)
1052 add_atdir(fname, dev, ino, mtime, atime)
1061 register u_int indx;
1067 * make sure this directory is not already in the table, if so just
1068 * return (the older entry always has the correct time). The only
1069 * way this will happen is when the same subtree can be traversed by
1070 * different args to pax and the -n option is aborting fts out of a
1071 * subtree before all the post-order visits have been made).
1073 indx = ((unsigned)ino) % A_TAB_SZ;
1074 if ((pt = atab[indx]) != NULL) {
1075 while (pt != NULL) {
1076 if ((pt->ino == ino) && (pt->dev == dev))
1082 * oops, already there. Leave it alone.
1089 * add it to the front of the hash chain
1091 if ((pt = (ATDIR *)malloc(sizeof(ATDIR))) != NULL) {
1092 if ((pt->name = strdup(fname)) != NULL) {
1097 pt->fow = atab[indx];
1101 (void)free((char *)pt);
1104 paxwarn(1, "Directory access time reset table ran out of memory");
1110 * look up a directory by inode and device number to obtain the access
1111 * and modification time you want to set to. If found, the modification
1112 * and access time parameters are set and the entry is removed from the
1113 * table (as it is no longer needed). These are for directories READ by
1116 * 0 if found, -1 if not found.
1121 get_atdir(dev_t dev, ino_t ino, time_t *mtime, time_t *atime)
1124 get_atdir(dev, ino, mtime, atime)
1132 register ATDIR **ppt;
1133 register u_int indx;
1138 * hash by inode and search the chain for an inode and device match
1140 indx = ((unsigned)ino) % A_TAB_SZ;
1141 if ((pt = atab[indx]) == NULL)
1144 ppt = &(atab[indx]);
1145 while (pt != NULL) {
1146 if ((pt->ino == ino) && (pt->dev == dev))
1149 * no match, go to next one
1156 * return if we did not find it.
1162 * found it. return the times and remove the entry from the table.
1167 (void)free((char *)pt->name);
1168 (void)free((char *)pt);
1173 * directory access mode and time storage routines (for directories CREATED
1176 * Pax requires that extracted directories, by default, have their access/mod
1177 * times and permissions set to the values specified in the archive. During the
1178 * actions of extracting (and creating the destination subtree during -rw copy)
1179 * directories extracted may be modified after being created. Even worse is
1180 * that these directories may have been created with file permissions which
1181 * prohibits any descendants of these directories from being extracted. When
1182 * directories are created by pax, access rights may be added to permit the
1183 * creation of files in their subtree. Every time pax creates a directory, the
1184 * times and file permissions specified by the archive are stored. After all
1185 * files have been extracted (or copied), these directories have their times
1186 * and file modes reset to the stored values. The directory info is restored in
1187 * reverse order as entries were added to the data file from root to leaf. To
1188 * restore atime properly, we must go backwards. The data file consists of
1189 * records with two parts, the file name followed by a DIRDATA trailer. The
1190 * fixed sized trailer contains the size of the name plus the off_t location in
1191 * the file. To restore we work backwards through the file reading the trailer
1192 * then the file name.
1197 * set up the directory time and file mode storage for directories CREATED
1200 * 0 if ok, -1 otherwise
1216 * unlink the file so it goes away at termination by itself
1218 memcpy(tempbase, _TFILE_BASE, sizeof(_TFILE_BASE));
1219 if ((dirfd = mkstemp(tempfile)) >= 0) {
1220 (void)unlink(tempfile);
1223 paxwarn(1, "Unable to create temporary file for directory times: %s",
1230 * add the mode and times for a newly CREATED directory
1231 * name is name of the directory, psb the stat buffer with the data in it,
1232 * frc_mode is a flag that says whether to force the setting of the mode
1233 * (ignoring the user set values for preserving file mode). Frc_mode is
1234 * for the case where we created a file and found that the resulting
1235 * directory was not writeable and the user asked for file modes to NOT
1236 * be preserved. (we have to preserve what was created by default, so we
1237 * have to force the setting at the end. this is stated explicitly in the
1243 add_dir(char *name, int nlen, struct stat *psb, int frc_mode)
1246 add_dir(name, nlen, psb, frc_mode)
1259 * get current position (where file name will start) so we can store it
1262 if ((dblk.npos = lseek(dirfd, 0L, SEEK_CUR)) < 0) {
1263 paxwarn(1,"Unable to store mode and times for directory: %s",name);
1268 * write the file name followed by the trailer
1270 dblk.nlen = nlen + 1;
1271 dblk.mode = psb->st_mode & 0xffff;
1272 dblk.mtime = psb->st_mtime;
1273 dblk.atime = psb->st_atime;
1274 dblk.frc_mode = frc_mode;
1275 if ((write(dirfd, name, dblk.nlen) == dblk.nlen) &&
1276 (write(dirfd, (char *)&dblk, sizeof(dblk)) == sizeof(dblk))) {
1281 paxwarn(1,"Unable to store mode and times for created directory: %s",name);
1287 * process all file modes and times stored for directories CREATED
1299 char name[PAXPATHLEN+1];
1306 * read backwards through the file and process each directory
1308 for (cnt = 0; cnt < dircnt; ++cnt) {
1310 * read the trailer, then the file name, if this fails
1313 if (lseek(dirfd, -((off_t)sizeof(dblk)), SEEK_CUR) < 0)
1315 if (read(dirfd,(char *)&dblk, sizeof(dblk)) != sizeof(dblk))
1317 if (lseek(dirfd, dblk.npos, SEEK_SET) < 0)
1319 if (read(dirfd, name, dblk.nlen) != dblk.nlen)
1321 if (lseek(dirfd, dblk.npos, SEEK_SET) < 0)
1325 * frc_mode set, make sure we set the file modes even if
1326 * the user didn't ask for it (see file_subs.c for more info)
1328 if (pmode || dblk.frc_mode)
1329 set_pmode(name, dblk.mode);
1330 if (patime || pmtime)
1331 set_ftime(name, dblk.mtime, dblk.atime, 0);
1337 paxwarn(1,"Unable to set mode and times for created directories");
1342 * database independent routines
1347 * hashes filenames to a u_int for hashing into a table. Looks at the tail
1348 * end of file, as this provides far better distribution than any other
1349 * part of the name. For performance reasons we only care about the last
1350 * MAXKEYLEN chars (should be at LEAST large enough to pick off the file
1351 * name). Was tested on 500,000 name file tree traversal from the root
1352 * and gave almost a perfectly uniform distribution of keys when used with
1353 * prime sized tables (MAXKEYLEN was 128 in test). Hashes (sizeof int)
1354 * chars at a time and pads with 0 for last addition.
1356 * the hash value of the string MOD (%) the table size.
1361 st_hash(char *name, int len, int tabsz)
1364 st_hash(name, len, tabsz)
1371 register char *dest;
1374 register u_int key = 0;
1380 * only look at the tail up to MAXKEYLEN, we do not need to waste
1381 * time here (remember these are pathnames, the tail is what will
1382 * spread out the keys)
1384 if (len > MAXKEYLEN) {
1385 pt = &(name[len - MAXKEYLEN]);
1391 * calculate the number of u_int size steps in the string and if
1392 * there is a runt to deal with
1394 steps = len/sizeof(u_int);
1395 res = len % sizeof(u_int);
1398 * add up the value of the string in unsigned integer sized pieces
1399 * too bad we cannot have unsigned int aligned strings, then we
1400 * could avoid the expensive copy.
1402 for (i = 0; i < steps; ++i) {
1403 end = pt + sizeof(u_int);
1404 dest = (char *)&val;
1411 * add in the runt padded with zero to the right
1416 dest = (char *)&val;
1423 * return the result mod the table size
1425 return(key % tabsz);