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 * 4. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 static char sccsid
[] = "@(#)ar_subs.c 8.2 (Berkeley) 4/18/94";
40 #include <sys/types.h>
54 static void wr_archive(ARCHD
*, int is_app
);
55 static int get_arc(void);
56 static int next_head(ARCHD
*);
57 extern sigset_t s_mask
;
60 * Routines which control the overall operation modes of pax as specified by
61 * the user: list, append, read ...
64 static char hdbuf
[BLKMULT
]; /* space for archive header on read */
65 u_long flcnt
; /* number of files processed */
69 * list the contents of an archive which match user supplied pattern(s)
70 * (no pattern matches all).
83 * figure out archive type; pass any format specific options to the
84 * archive option processing routine; call the format init routine. We
85 * also save current time for ls_list() so we do not make a system
86 * call for each file we need to print. If verbose (vflag) start up
87 * the name and group caches.
89 if ((get_arc() < 0) || ((*frmt
->options
)() < 0) ||
90 ((*frmt
->st_rd
)() < 0))
93 if (vflag
&& ((uidtb_start() < 0) || (gidtb_start() < 0)))
99 * step through the archive until the format says it is done
101 while (next_head(arcn
) == 0) {
103 * check for pattern, and user specified options match.
104 * When all patterns are matched we are done.
106 if ((res
= pat_match(arcn
)) < 0)
109 if ((res
== 0) && (sel_chk(arcn
) == 0)) {
111 * pattern resulted in a selected file
113 if (pat_sel(arcn
) < 0)
117 * modify the name as requested by the user if name
118 * survives modification, do a listing of the file
120 if ((res
= mod_name(arcn
)) < 0)
123 ls_list(arcn
, now
, stdout
);
127 * skip to next archive format header using values calculated
128 * by the format header read routine
130 if (rd_skip(arcn
->skip
+ arcn
->pad
) == 1)
135 * all done, let format have a chance to cleanup, and make sure that
136 * the patterns supplied by the user were all matched
138 (void)(*frmt
->end_rd
)();
139 (void)sigprocmask(SIG_BLOCK
, &s_mask
, NULL
);
146 * extract the member(s) of an archive as specified by user supplied
147 * pattern(s) (no patterns extracts all members)
163 * figure out archive type; pass any format specific options to the
164 * archive option processing routine; call the format init routine;
165 * start up the directory modification time and access mode database
167 if ((get_arc() < 0) || ((*frmt
->options
)() < 0) ||
168 ((*frmt
->st_rd
)() < 0) || (dir_start() < 0))
172 * When we are doing interactive rename, we store the mapping of names
173 * so we can fix up hard links files later in the archive.
175 if (iflag
&& (name_start() < 0))
181 * step through each entry on the archive until the format read routine
184 while (next_head(arcn
) == 0) {
187 * check for pattern, and user specified options match. When
188 * all the patterns are matched we are done
190 if ((res
= pat_match(arcn
)) < 0)
193 if ((res
> 0) || (sel_chk(arcn
) != 0)) {
195 * file is not selected. skip past any file data and
196 * padding and go back for the next archive member
198 (void)rd_skip(arcn
->skip
+ arcn
->pad
);
203 * with -u or -D only extract when the archive member is newer
204 * than the file with the same name in the file system (nos
205 * test of being the same type is required).
206 * NOTE: this test is done BEFORE name modifications as
207 * specified by pax. this operation can be confusing to the
208 * user who might expect the test to be done on an existing
209 * file AFTER the name mod. In honesty the pax spec is probably
210 * flawed in this respect.
212 if ((uflag
|| Dflag
) && ((lstat(arcn
->name
, &sb
) == 0))) {
213 if (uflag
&& Dflag
) {
214 if ((arcn
->sb
.st_mtime
<= sb
.st_mtime
) &&
215 (arcn
->sb
.st_ctime
<= sb
.st_ctime
)) {
216 (void)rd_skip(arcn
->skip
+ arcn
->pad
);
220 if (arcn
->sb
.st_ctime
<= sb
.st_ctime
) {
221 (void)rd_skip(arcn
->skip
+ arcn
->pad
);
224 } else if (arcn
->sb
.st_mtime
<= sb
.st_mtime
) {
225 (void)rd_skip(arcn
->skip
+ arcn
->pad
);
231 * this archive member is now been selected. modify the name.
233 if ((pat_sel(arcn
) < 0) || ((res
= mod_name(arcn
)) < 0))
237 * a bad name mod, skip and purge name from link table
240 (void)rd_skip(arcn
->skip
+ arcn
->pad
);
245 * Non standard -Y and -Z flag. When the existing file is
246 * same age or newer skip
248 if ((Yflag
|| Zflag
) && ((lstat(arcn
->name
, &sb
) == 0))) {
249 if (Yflag
&& Zflag
) {
250 if ((arcn
->sb
.st_mtime
<= sb
.st_mtime
) &&
251 (arcn
->sb
.st_ctime
<= sb
.st_ctime
)) {
252 (void)rd_skip(arcn
->skip
+ arcn
->pad
);
256 if (arcn
->sb
.st_ctime
<= sb
.st_ctime
) {
257 (void)rd_skip(arcn
->skip
+ arcn
->pad
);
260 } else if (arcn
->sb
.st_mtime
<= sb
.st_mtime
) {
261 (void)rd_skip(arcn
->skip
+ arcn
->pad
);
268 ls_list(arcn
, now
, listf
);
270 (void)fputs(arcn
->name
, listf
);
276 * if required, chdir around.
278 if ((arcn
->pat
!= NULL
) && (arcn
->pat
->chdname
!= NULL
))
279 if (chdir(arcn
->pat
->chdname
) != 0)
280 syswarn(1, errno
, "Cannot chdir to %s",
284 * all ok, extract this member based on type
286 if ((arcn
->type
!= PAX_REG
) && (arcn
->type
!= PAX_CTG
)) {
288 * process archive members that are not regular files.
289 * throw out padding and any data that might follow the
290 * header (as determined by the format).
292 if ((arcn
->type
== PAX_HLK
) || (arcn
->type
== PAX_HRG
))
293 res
= lnk_creat(arcn
);
295 res
= node_creat(arcn
);
297 (void)rd_skip(arcn
->skip
+ arcn
->pad
);
301 if (vflag
&& vfpart
) {
302 (void)putc('\n', listf
);
308 * we have a file with data here. If we can not create it, skip
309 * over the data and purge the name from hard link table
311 if ((fd
= file_creat(arcn
)) < 0) {
312 (void)rd_skip(arcn
->skip
+ arcn
->pad
);
317 * extract the file from the archive and skip over padding and
318 * any unprocessed data
320 res
= (*frmt
->rd_data
)(arcn
, fd
, &cnt
);
321 file_close(arcn
, fd
);
322 if (vflag
&& vfpart
) {
323 (void)putc('\n', listf
);
327 (void)rd_skip(cnt
+ arcn
->pad
);
330 * if required, chdir around.
332 if ((arcn
->pat
!= NULL
) && (arcn
->pat
->chdname
!= NULL
))
333 if (fchdir(cwdfd
) != 0)
335 "Can't fchdir to starting directory");
339 * all done, restore directory modes and times as required; make sure
340 * all patterns supplied by the user were matched; block off signals
341 * to avoid chance for multiple entry into the cleanup code.
343 (void)(*frmt
->end_rd
)();
344 (void)sigprocmask(SIG_BLOCK
, &s_mask
, NULL
);
352 * Write an archive. used in both creating a new archive and appends on
353 * previously written archive.
357 wr_archive(ARCHD
*arcn
, int is_app
)
368 * if this format supports hard link storage, start up the database
371 if (((hlk
= frmt
->hlk
) == 1) && (lnk_start() < 0))
375 * start up the file traversal code and format specific write
377 if ((ftree_start() < 0) || ((*frmt
->st_wr
)() < 0))
382 * When we are doing interactive rename, we store the mapping of names
383 * so we can fix up hard links files later in the archive.
385 if (iflag
&& (name_start() < 0))
389 * if this not append, and there are no files, we do no write a trailer
396 * while there are files to archive, process them one at at time
398 while (next_file(arcn
) == 0) {
400 * check if this file meets user specified options match.
402 if (sel_chk(arcn
) != 0) {
409 * only archive if this file is newer than a file with
410 * the same name that is already stored on the archive
412 if ((res
= chk_ftime(arcn
)) < 0)
419 * this file is considered selected now. see if this is a hard
420 * link to a file already stored
423 if (hlk
&& (chk_lnk(arcn
) < 0))
426 if ((arcn
->type
== PAX_REG
) || (arcn
->type
== PAX_HRG
) ||
427 (arcn
->type
== PAX_CTG
)) {
429 * we will have to read this file. by opening it now we
430 * can avoid writing a header to the archive for a file
431 * we were later unable to read (we also purge it from
434 if ((fd
= open(arcn
->org_name
, O_RDONLY
, 0)) < 0) {
435 syswarn(1,errno
, "Unable to open %s to read",
443 * Now modify the name as requested by the user
445 if ((res
= mod_name(arcn
)) < 0) {
447 * name modification says to skip this file, close the
448 * file and purge link table entry
450 rdfile_close(arcn
, &fd
);
455 if ((res
> 0) || (docrc
&& (set_crc(arcn
, fd
) < 0))) {
457 * unable to obtain the crc we need, close the file,
458 * purge link table entry
460 rdfile_close(arcn
, &fd
);
467 ls_list(arcn
, now
, listf
);
469 (void)fputs(arcn
->name
, listf
);
476 * looks safe to store the file, have the format specific
477 * routine write routine store the file header on the archive
479 if ((res
= (*wrf
)(arcn
)) < 0) {
480 rdfile_close(arcn
, &fd
);
486 * format write says no file data needs to be stored
487 * so we are done messing with this file
489 if (vflag
&& vfpart
) {
490 (void)putc('\n', listf
);
493 rdfile_close(arcn
, &fd
);
498 * Add file data to the archive, quit on write error. if we
499 * cannot write the entire file contents to the archive we
500 * must pad the archive to replace the missing file data
501 * (otherwise during an extract the file header for the file
502 * which FOLLOWS this one will not be where we expect it to
505 res
= (*frmt
->wr_data
)(arcn
, fd
, &cnt
);
506 rdfile_close(arcn
, &fd
);
507 if (vflag
&& vfpart
) {
508 (void)putc('\n', listf
);
515 * pad as required, cnt is number of bytes not written
517 if (((cnt
> 0) && (wr_skip(cnt
) < 0)) ||
518 ((arcn
->pad
> 0) && (wr_skip(arcn
->pad
) < 0)))
523 * tell format to write trailer; pad to block boundary; reset directory
524 * mode/access times, and check if all patterns supplied by the user
525 * were matched. block off signals to avoid chance for multiple entry
526 * into the cleanup code
532 (void)sigprocmask(SIG_BLOCK
, &s_mask
, NULL
);
541 * Add file to previously written archive. Archive format specified by the
542 * user must agree with archive. The archive is read first to collect
543 * modification times (if -u) and locate the archive trailer. The archive
544 * is positioned in front of the record with the trailer and wr_archive()
545 * is called to add the new members.
546 * PAX IMPLEMENTATION DETAIL NOTE:
547 * -u is implemented by adding the new members to the end of the archive.
548 * Care is taken so that these do not end up as links to the older
549 * version of the same file already stored in the archive. It is expected
550 * when extraction occurs these newer versions will over-write the older
551 * ones stored "earlier" in the archive (this may be a bad assumption as
552 * it depends on the implementation of the program doing the extraction).
553 * It is really difficult to splice in members without either re-writing
554 * the entire archive (from the point were the old version was), or having
555 * assistance of the format specification in terms of a special update
556 * header that invalidates a previous archive record. The POSIX spec left
557 * the method used to implement -u unspecified. This pax is able to
558 * over write existing files that it creates.
575 * Do not allow an append operation if the actual archive is of a
576 * different format than the user specified format.
580 if ((orgfrmt
!= NULL
) && (orgfrmt
!= frmt
)) {
581 paxwarn(1, "Cannot mix current archive format %s with %s",
582 frmt
->name
, orgfrmt
->name
);
587 * pass the format any options and start up format
589 if (((*frmt
->options
)() < 0) || ((*frmt
->st_rd
)() < 0))
593 * if we only are adding members that are newer, we need to save the
594 * mod times for all files we see.
596 if (uflag
&& (ftime_start() < 0))
600 * some archive formats encode hard links by recording the device and
601 * file serial number (inode) but copy the file anyway (multiple times)
602 * to the archive. When we append, we run the risk that newly added
603 * files may have the same device and inode numbers as those recorded
604 * on the archive but during a previous run. If this happens, when the
605 * archive is extracted we get INCORRECT hard links. We avoid this by
606 * remapping the device numbers so that newly added files will never
607 * use the same device number as one found on the archive. remapping
608 * allows new members to safely have links among themselves. remapping
609 * also avoids problems with file inode (serial number) truncations
610 * when the inode number is larger than storage space in the archive
611 * header. See the remap routines for more details.
613 if ((udev
= frmt
->udev
) && (dev_start() < 0))
617 * reading the archive may take a long time. If verbose tell the user
621 "%s: Reading archive to position at the end...", argv0
);
626 * step through the archive until the format says it is done
628 while (next_head(arcn
) == 0) {
630 * check if this file meets user specified options.
632 if (sel_chk(arcn
) != 0) {
633 if (rd_skip(arcn
->skip
+ arcn
->pad
) == 1)
640 * see if this is the newest version of this file has
641 * already been seen, if so skip.
643 if ((res
= chk_ftime(arcn
)) < 0)
646 if (rd_skip(arcn
->skip
+ arcn
->pad
) == 1)
653 * Store this device number. Device numbers seen during the
654 * read phase of append will cause newly appended files with a
655 * device number seen in the old part of the archive to be
656 * remapped to an unused device number.
658 if ((udev
&& (add_dev(arcn
) < 0)) ||
659 (rd_skip(arcn
->skip
+ arcn
->pad
) == 1))
664 * done, finish up read and get the number of bytes to back up so we
665 * can add new members. The format might have used the hard link table,
668 tlen
= (*frmt
->end_rd
)();
672 * try to position for write, if this fails quit. if any error occurs,
673 * we will refuse to write
675 if (appnd_start(tlen
) < 0)
679 * tell the user we are done reading.
681 if (vflag
&& vfpart
) {
682 (void)fputs("done.\n", listf
);
687 * go to the writing phase to add the new members
694 * write a new archive
703 * if we only are adding members that are newer, we need to save the
704 * mod times for all files; set up for writing; pass the format any
705 * options write the archive
707 if ((uflag
&& (ftime_start() < 0)) || (wr_start() < 0))
709 if ((*frmt
->options
)() < 0)
712 wr_archive(&archd
, 0);
717 * copy files from one part of the file system to another. this does not
718 * use any archive storage. The EFFECT OF THE COPY IS THE SAME as if an
719 * archive was written and then extracted in the destination directory
720 * (except the files are forced to be under the destination directory).
735 char dirbuf
[PAXPATHLEN
+1];
739 * set up the destination dir path and make sure it is a directory. We
740 * make sure we have a trailing / on the destination
742 dlen
= l_strncpy(dirbuf
, dirptr
, sizeof(dirbuf
) - 1);
743 dest_pt
= dirbuf
+ dlen
;
744 if (*(dest_pt
-1) != '/') {
749 drem
= PAXPATHLEN
- dlen
;
751 if (stat(dirptr
, &sb
) < 0) {
752 syswarn(1, errno
, "Cannot access destination directory %s",
756 if (!S_ISDIR(sb
.st_mode
)) {
757 paxwarn(1, "Destination is not a directory %s", dirptr
);
762 * start up the hard link table; file traversal routines and the
763 * modification time and access mode database
765 if ((lnk_start() < 0) || (ftree_start() < 0) || (dir_start() < 0))
769 * When we are doing interactive rename, we store the mapping of names
770 * so we can fix up hard links files later in the archive.
772 if (iflag
&& (name_start() < 0))
776 * set up to cp file trees
781 * while there are files to archive, process them
783 while (next_file(arcn
) == 0) {
787 * check if this file meets user specified options
789 if (sel_chk(arcn
) != 0) {
795 * if there is already a file in the destination directory with
796 * the same name and it is newer, skip the one stored on the
798 * NOTE: this test is done BEFORE name modifications as
799 * specified by pax. this can be confusing to the user who
800 * might expect the test to be done on an existing file AFTER
801 * the name mod. In honesty the pax spec is probably flawed in
804 if (uflag
|| Dflag
) {
806 * create the destination name
808 if (*(arcn
->name
) == '/')
812 if ((arcn
->nlen
- res
) > drem
) {
813 paxwarn(1, "Destination pathname too long %s",
817 (void)strncpy(dest_pt
, arcn
->name
+ res
, drem
);
818 dirbuf
[PAXPATHLEN
] = '\0';
821 * if existing file is same age or newer skip
823 res
= lstat(dirbuf
, &sb
);
827 if (uflag
&& Dflag
) {
828 if ((arcn
->sb
.st_mtime
<=sb
.st_mtime
) &&
829 (arcn
->sb
.st_ctime
<=sb
.st_ctime
))
832 if (arcn
->sb
.st_ctime
<= sb
.st_ctime
)
834 } else if (arcn
->sb
.st_mtime
<= sb
.st_mtime
)
840 * this file is considered selected. See if this is a hard link
841 * to a previous file; modify the name as requested by the
842 * user; set the final destination.
845 if ((chk_lnk(arcn
) < 0) || ((res
= mod_name(arcn
)) < 0))
847 if ((res
> 0) || (set_dest(arcn
, dirbuf
, dlen
) < 0)) {
849 * skip file, purge from link table
856 * Non standard -Y and -Z flag. When the exisiting file is
857 * same age or newer skip
859 if ((Yflag
|| Zflag
) && ((lstat(arcn
->name
, &sb
) == 0))) {
860 if (Yflag
&& Zflag
) {
861 if ((arcn
->sb
.st_mtime
<= sb
.st_mtime
) &&
862 (arcn
->sb
.st_ctime
<= sb
.st_ctime
))
865 if (arcn
->sb
.st_ctime
<= sb
.st_ctime
)
867 } else if (arcn
->sb
.st_mtime
<= sb
.st_mtime
)
872 (void)fputs(arcn
->name
, listf
);
878 * try to create a hard link to the src file if requested
879 * but make sure we are not trying to overwrite ourselves.
882 res
= cross_lnk(arcn
);
884 res
= chk_same(arcn
);
886 if (vflag
&& vfpart
) {
887 (void)putc('\n', listf
);
894 * have to create a new file
896 if ((arcn
->type
!= PAX_REG
) && (arcn
->type
!= PAX_CTG
)) {
898 * create a link or special file
900 if ((arcn
->type
== PAX_HLK
) || (arcn
->type
== PAX_HRG
))
901 res
= lnk_creat(arcn
);
903 res
= node_creat(arcn
);
906 if (vflag
&& vfpart
) {
907 (void)putc('\n', listf
);
914 * have to copy a regular file to the destination directory.
915 * first open source file and then create the destination file
917 if ((fdsrc
= open(arcn
->org_name
, O_RDONLY
, 0)) < 0) {
918 syswarn(1, errno
, "Unable to open %s to read",
923 if ((fddest
= file_creat(arcn
)) < 0) {
924 rdfile_close(arcn
, &fdsrc
);
930 * copy source file data to the destination file
932 cp_file(arcn
, fdsrc
, fddest
);
933 file_close(arcn
, fddest
);
934 rdfile_close(arcn
, &fdsrc
);
936 if (vflag
&& vfpart
) {
937 (void)putc('\n', listf
);
943 * restore directory modes and times as required; make sure all
944 * patterns were selected block off signals to avoid chance for
945 * multiple entry into the cleanup code.
947 (void)sigprocmask(SIG_BLOCK
, &s_mask
, NULL
);
955 * try to find a valid header in the archive. Uses format specific
956 * routines to extract the header and id the trailer. Trailers may be
957 * located within a valid header or in an invalid header (the location
958 * is format specific. The inhead field from the option table tells us
959 * where to look for the trailer).
960 * We keep reading (and resyncing) until we get enough contiguous data
961 * to check for a header. If we cannot find one, we shift by a byte
962 * add a new byte from the archive to the end of the buffer and try again.
963 * If we get a read error, we throw out what we have (as we must have
964 * contiguous data) and start over again.
965 * ASSUMED: headers fit within a BLKMULT header.
967 * 0 if we got a header, -1 if we are unable to ever find another one
968 * (we reached the end of input, or we reached the limit on retries. see
969 * the specs for rd_wrbuf() for more details)
973 next_head(ARCHD
*arcn
)
980 int in_resync
= 0; /* set when we are in resync mode */
981 int cnt
= 0; /* counter for trailer function */
982 int first
= 1; /* on 1st read, EOF isn't premature. */
985 * set up initial conditions, we want a whole frmt->hsz block as we
988 res
= hsz
= frmt
->hsz
;
993 * keep looping until we get a contiguous FULL buffer
994 * (frmt->hsz is the proper size)
997 if ((ret
= rd_wrbuf(hdend
, res
)) == res
)
1001 * If we read 0 bytes (EOF) from an archive when we
1002 * expect to find a header, we have stepped upon
1003 * an archive without the customary block of zeroes
1004 * end marker. It's just stupid to error out on
1005 * them, so exit gracefully.
1007 if (first
&& ret
== 0)
1012 * some kind of archive read problem, try to resync the
1013 * storage device, better give the user the bad news.
1015 if ((ret
== 0) || (rd_sync() < 0)) {
1016 paxwarn(1,"Premature end of file on archive read");
1022 "Archive I/O error, cannot continue");
1025 paxwarn(1,"Archive I/O error. Trying to recover.");
1030 * oh well, throw it all out and start over
1037 * ok we have a contiguous buffer of the right size. Call the
1038 * format read routine. If this was not a valid header and this
1039 * format stores trailers outside of the header, call the
1040 * format specific trailer routine to check for a trailer. We
1041 * have to watch out that we do not mis-identify file data or
1042 * block padding as a header or trailer. Format specific
1043 * trailer functions must NOT check for the trailer while we
1044 * are running in resync mode. Some trailer functions may tell
1045 * us that this block cannot contain a valid header either, so
1046 * we then throw out the entire block and start over.
1048 if ((*frmt
->rd
)(arcn
, hdbuf
) == 0)
1051 if (!frmt
->inhead
) {
1053 * this format has trailers outside of valid headers
1055 if ((ret
= (*frmt
->trail_tar
)(hdbuf
,in_resync
,&cnt
)) == 0){
1057 * valid trailer found, drain input as required
1065 * we are in resync and we were told to throw
1066 * the whole block out because none of the
1067 * bytes in this block can be used to form a
1077 * Brute force section.
1078 * not a valid header. We may be able to find a header yet. So
1079 * we shift over by one byte, and set up to read one byte at a
1080 * time from the archive and place it at the end of the buffer.
1081 * We will keep moving byte at a time until we find a header or
1082 * get a read error and have to start over.
1086 paxwarn(1,"Unable to append, archive header flaw");
1089 paxwarn(1,"Invalid header, starting valid header search.");
1092 memmove(hdbuf
, hdbuf
+1, shftsz
);
1094 hdend
= hdbuf
+ shftsz
;
1098 * ok got a valid header, check for trailer if format encodes it in the
1101 if (frmt
->inhead
&& ((*frmt
->trail_cpio
)(arcn
) == 0)) {
1103 * valid trailer found, drain input as required
1115 * Figure out what format an archive is. Handles archive with flaws by
1116 * brute force searches for a legal header in any supported format. The
1117 * format id routines have to be careful to NOT mis-identify a format.
1118 * ASSUMED: headers fit within a BLKMULT header.
1120 * 0 if archive found -1 otherwise
1129 int minhd
= BLKMULT
;
1134 * find the smallest header size in all archive formats and then set up
1135 * to read the archive.
1137 for (i
= 0; ford
[i
] >= 0; ++i
) {
1138 if (fsub
[ford
[i
]].hsz
< minhd
)
1139 minhd
= fsub
[ford
[i
]].hsz
;
1149 * fill the buffer with at least the smallest header
1151 i
= rd_wrbuf(hdend
, res
);
1158 * if we cannot recover from a read error quit
1160 if ((i
== 0) || (rd_sync() < 0))
1164 * when we get an error none of the data we already
1165 * have can be used to create a legal header (we just
1166 * got an error in the middle), so we throw it all out
1167 * and refill the buffer with fresh data.
1175 paxwarn(1,"Cannot identify format. Searching...");
1181 * we have at least the size of the smallest header in any
1182 * archive format. Look to see if we have a match. The array
1183 * ford[] is used to specify the header id order to reduce the
1184 * chance of incorrectly id'ing a valid header (some formats
1185 * may be subsets of each other and the order would then be
1188 for (i
= 0; ford
[i
] >= 0; ++i
) {
1189 if ((*fsub
[ford
[i
]].id
)(hdbuf
, hdsz
) < 0)
1191 frmt
= &(fsub
[ford
[i
]]);
1193 * yuck, to avoid slow special case code in the extract
1194 * routines, just push this header back as if it was
1195 * not seen. We have left extra space at start of the
1196 * buffer for this purpose. This is a bit ugly, but
1197 * adding all the special case code is far worse.
1204 * We have a flawed archive, no match. we start searching, but
1205 * we never allow additions to flawed archives
1210 paxwarn(1, "Cannot identify format. Searching...");
1215 * brute force search for a header that we can id.
1216 * we shift through byte at a time. this is slow, but we cannot
1217 * determine the nature of the flaw in the archive in a
1221 memmove(hdbuf
, hdbuf
+1, hdsz
);
1222 res
= BLKMULT
- hdsz
;
1223 hdend
= hdbuf
+ hdsz
;
1233 * we cannot find a header, bow, apologize and quit
1235 paxwarn(1, "Sorry, unable to determine archive format.");