Remove not needed void casts.
[dragonfly.git] / bin / pax / ar_io.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 * @(#)ar_io.c 8.2 (Berkeley) 4/18/94
38 * $FreeBSD: src/bin/pax/ar_io.c,v 1.12.2.1 2001/08/01 05:03:11 obrien Exp $
57fed2af 39 * $DragonFly: src/bin/pax/ar_io.c,v 1.9 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/ioctl.h>
44#include <sys/mtio.h>
45#include <sys/stat.h>
46#include <sys/wait.h>
47#include <err.h>
48#include <errno.h>
49#include <fcntl.h>
50#include <signal.h>
51#include <stdio.h>
52#include <string.h>
53#include <stdlib.h>
54#include <unistd.h>
55#include "pax.h"
56#include "options.h"
57#include "extern.h"
58
59/*
60 * Routines which deal directly with the archive I/O device/file.
61 */
62
63#define DMOD 0666 /* default mode of created archives */
64#define EXT_MODE O_RDONLY /* open mode for list/extract */
65#define AR_MODE (O_WRONLY | O_CREAT | O_TRUNC) /* mode for archive */
66#define APP_MODE O_RDWR /* mode for append */
67#define STDO "<STDOUT>" /* pseudo name for stdout */
68#define STDN "<STDIN>" /* pseudo name for stdin */
69static int arfd = -1; /* archive file descriptor */
70static int artyp = ISREG; /* archive type: file/FIFO/tape */
71static int arvol = 1; /* archive volume number */
72static int lstrval = -1; /* return value from last i/o */
73static int io_ok; /* i/o worked on volume after resync */
74static int did_io; /* did i/o ever occur on volume? */
75static int done; /* set via tty termination */
76static struct stat arsb; /* stat of archive device at open */
77static int invld_rec; /* tape has out of spec record size */
78static int wr_trail = 1; /* trailer was rewritten in append */
79static int can_unlnk = 0; /* do we unlink null archives? */
80char *arcname; /* printable name of archive */
81const char *gzip_program; /* name of gzip program */
82static pid_t zpid = -1; /* pid of child process */
83
9dbf638f 84static int get_phys (void);
984263bc 85extern sigset_t s_mask;
9dbf638f 86static void ar_start_gzip (int, const char *, int);
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87
88/*
89 * ar_open()
90 * Opens the next archive volume. Determines the type of the device and
91 * sets up block sizes as required by the archive device and the format.
92 * Note: we may be called with name == NULL on the first open only.
93 * Return:
94 * -1 on failure, 0 otherwise
95 */
96
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97int
98ar_open(char *name)
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99{
100 struct mtget mb;
101
102 if (arfd != -1)
57fed2af 103 close(arfd);
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104 arfd = -1;
105 can_unlnk = did_io = io_ok = invld_rec = 0;
106 artyp = ISREG;
107 flcnt = 0;
108
109 /*
110 * open based on overall operation mode
111 */
112 switch (act) {
113 case LIST:
114 case EXTRACT:
115 if (name == NULL) {
116 arfd = STDIN_FILENO;
117 arcname = STDN;
118 } else if ((arfd = open(name, EXT_MODE, DMOD)) < 0)
119 syswarn(0, errno, "Failed open to read on %s", name);
120 if (arfd != -1 && gzip_program != NULL)
121 ar_start_gzip(arfd, gzip_program, 0);
122 break;
123 case ARCHIVE:
124 if (name == NULL) {
125 arfd = STDOUT_FILENO;
126 arcname = STDO;
127 } else if ((arfd = open(name, AR_MODE, DMOD)) < 0)
128 syswarn(0, errno, "Failed open to write on %s", name);
129 else
130 can_unlnk = 1;
131 if (arfd != -1 && gzip_program != NULL)
132 ar_start_gzip(arfd, gzip_program, 1);
133 break;
134 case APPND:
135 if (name == NULL) {
136 arfd = STDOUT_FILENO;
137 arcname = STDO;
138 } else if ((arfd = open(name, APP_MODE, DMOD)) < 0)
139 syswarn(0, errno, "Failed open to read/write on %s",
140 name);
141 break;
142 case COPY:
143 /*
144 * arfd not used in COPY mode
145 */
146 arcname = "<NONE>";
147 lstrval = 1;
148 return(0);
149 }
150 if (arfd < 0)
151 return(-1);
152
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153 if (chdname != NULL) {
154 if (chdir(chdname) != 0) {
984263bc 155 syswarn(1, errno, "Failed chdir to %s", chdname);
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156 return(-1);
157 }
158 }
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159 /*
160 * set up is based on device type
161 */
162 if (fstat(arfd, &arsb) < 0) {
163 syswarn(0, errno, "Failed stat on %s", arcname);
57fed2af 164 close(arfd);
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165 arfd = -1;
166 can_unlnk = 0;
167 return(-1);
168 }
169 if (S_ISDIR(arsb.st_mode)) {
170 paxwarn(0, "Cannot write an archive on top of a directory %s",
171 arcname);
57fed2af 172 close(arfd);
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173 arfd = -1;
174 can_unlnk = 0;
175 return(-1);
176 }
177
178 if (S_ISCHR(arsb.st_mode))
179 artyp = ioctl(arfd, MTIOCGET, &mb) ? ISCHR : ISTAPE;
180 else if (S_ISBLK(arsb.st_mode))
181 artyp = ISBLK;
182 else if ((lseek(arfd, (off_t)0L, SEEK_CUR) == -1) && (errno == ESPIPE))
183 artyp = ISPIPE;
184 else
185 artyp = ISREG;
186
187 /*
188 * make sure we beyond any doubt that we only can unlink regular files
189 * we created
190 */
191 if (artyp != ISREG)
192 can_unlnk = 0;
193 /*
194 * if we are writing, we are done
195 */
196 if (act == ARCHIVE) {
197 blksz = rdblksz = wrblksz;
198 lstrval = 1;
199 return(0);
200 }
201
202 /*
203 * set default blksz on read. APPNDs writes rdblksz on the last volume
204 * On all new archive volumes, we shift to wrblksz (if the user
205 * specified one, otherwize we will continue to use rdblksz). We
206 * must to set blocksize based on what kind of device the archive is
207 * stored.
208 */
209 switch(artyp) {
210 case ISTAPE:
211 /*
212 * Tape drives come in at least two flavors. Those that support
213 * variable sized records and those that have fixed sized
214 * records. They must be treated differently. For tape drives
215 * that support variable sized records, we must make large
216 * reads to make sure we get the entire record, otherwise we
217 * will just get the first part of the record (up to size we
218 * asked). Tapes with fixed sized records may or may not return
219 * multiple records in a single read. We really do not care
220 * what the physical record size is UNLESS we are going to
221 * append. (We will need the physical block size to rewrite
222 * the trailer). Only when we are appending do we go to the
223 * effort to figure out the true PHYSICAL record size.
224 */
225 blksz = rdblksz = MAXBLK;
226 break;
227 case ISPIPE:
228 case ISBLK:
229 case ISCHR:
230 /*
231 * Blocksize is not a major issue with these devices (but must
232 * be kept a multiple of 512). If the user specified a write
233 * block size, we use that to read. Under append, we must
234 * always keep blksz == rdblksz. Otherwise we go ahead and use
235 * the device optimal blocksize as (and if) returned by stat
236 * and if it is within pax specs.
237 */
238 if ((act == APPND) && wrblksz) {
239 blksz = rdblksz = wrblksz;
240 break;
241 }
242
243 if ((arsb.st_blksize > 0) && (arsb.st_blksize < MAXBLK) &&
244 ((arsb.st_blksize % BLKMULT) == 0))
245 rdblksz = arsb.st_blksize;
246 else
247 rdblksz = DEVBLK;
248 /*
249 * For performance go for large reads when we can without harm
250 */
251 if ((act == APPND) || (artyp == ISCHR))
252 blksz = rdblksz;
253 else
254 blksz = MAXBLK;
255 break;
256 case ISREG:
257 /*
258 * if the user specified wrblksz works, use it. Under appends
259 * we must always keep blksz == rdblksz
260 */
261 if ((act == APPND) && wrblksz && ((arsb.st_size%wrblksz)==0)){
262 blksz = rdblksz = wrblksz;
263 break;
264 }
265 /*
266 * See if we can find the blocking factor from the file size
267 */
268 for (rdblksz = MAXBLK; rdblksz > 0; rdblksz -= BLKMULT)
269 if ((arsb.st_size % rdblksz) == 0)
270 break;
271 /*
272 * When we cannot find a match, we may have a flawed archive.
273 */
274 if (rdblksz <= 0)
275 rdblksz = FILEBLK;
276 /*
277 * for performance go for large reads when we can
278 */
279 if (act == APPND)
280 blksz = rdblksz;
281 else
282 blksz = MAXBLK;
283 break;
284 default:
285 /*
286 * should never happen, worse case, slow...
287 */
288 blksz = rdblksz = BLKMULT;
289 break;
290 }
291 lstrval = 1;
292 return(0);
293}
294
295/*
296 * ar_close()
297 * closes archive device, increments volume number, and prints i/o summary
298 */
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299void
300ar_close(void)
984263bc 301{
75b7852c 302 int status;
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303
304 if (arfd < 0) {
305 did_io = io_ok = flcnt = 0;
306 return;
307 }
308
309 /*
310 * Close archive file. This may take a LONG while on tapes (we may be
311 * forced to wait for the rewind to complete) so tell the user what is
312 * going on (this avoids the user hitting control-c thinking pax is
313 * broken).
314 */
315 if (vflag && (artyp == ISTAPE)) {
316 if (vfpart)
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317 putc('\n', listf);
318 fprintf(listf,
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319 "%s: Waiting for tape drive close to complete...",
320 argv0);
57fed2af 321 fflush(listf);
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322 }
323
324 /*
325 * if nothing was written to the archive (and we created it), we remove
326 * it
327 */
328 if (can_unlnk && (fstat(arfd, &arsb) == 0) && (S_ISREG(arsb.st_mode)) &&
329 (arsb.st_size == 0)) {
57fed2af 330 unlink(arcname);
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331 can_unlnk = 0;
332 }
333
334 /*
335 * for a quick extract/list, pax frequently exits before the child
336 * process is done
337 */
75b7852c 338 if ((act == LIST || act == EXTRACT) && nflag && zpid > 0)
984263bc 339 kill(zpid, SIGINT);
984263bc 340
57fed2af 341 close(arfd);
984263bc 342
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343 /* Do not exit before child to ensure data integrity */
344 if (zpid > 0)
345 waitpid(zpid, &status, 0);
346
984263bc 347 if (vflag && (artyp == ISTAPE)) {
57fed2af 348 fputs("done.\n", listf);
984263bc 349 vfpart = 0;
57fed2af 350 fflush(listf);
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351 }
352 arfd = -1;
353
354 if (!io_ok && !did_io) {
355 flcnt = 0;
356 return;
357 }
358 did_io = io_ok = 0;
359
360 /*
361 * The volume number is only increased when the last device has data
362 * and we have already determined the archive format.
363 */
364 if (frmt != NULL)
365 ++arvol;
366
367 if (!vflag) {
368 flcnt = 0;
369 return;
370 }
371
372 /*
373 * Print out a summary of I/O for this archive volume.
374 */
375 if (vfpart) {
57fed2af 376 putc('\n', listf);
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377 vfpart = 0;
378 }
379
380 /*
381 * If we have not determined the format yet, we just say how many bytes
382 * we have skipped over looking for a header to id. there is no way we
383 * could have written anything yet.
384 */
385 if (frmt == NULL) {
386# ifdef NET2_STAT
57fed2af 387 fprintf(listf, "%s: unknown format, %lu bytes skipped.\n",
984263bc 388# else
57fed2af 389 fprintf(listf, "%s: unknown format, %qu bytes skipped.\n",
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390# endif
391 argv0, rdcnt);
57fed2af 392 fflush(listf);
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393 flcnt = 0;
394 return;
395 }
396
397 if (strcmp(NM_CPIO, argv0) == 0)
57fed2af 398 fprintf(listf, "%qu blocks\n", (rdcnt ? rdcnt : wrcnt) / 5120);
984263bc 399 else if (strcmp(NM_TAR, argv0) != 0)
57fed2af 400 fprintf(listf,
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401# ifdef NET2_STAT
402 "%s: %s vol %d, %lu files, %lu bytes read, %lu bytes written.\n",
403# else
404 "%s: %s vol %d, %lu files, %qu bytes read, %qu bytes written.\n",
405# endif
406 argv0, frmt->name, arvol-1, flcnt, rdcnt, wrcnt);
57fed2af 407 fflush(listf);
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408 flcnt = 0;
409}
410
411/*
412 * ar_drain()
413 * drain any archive format independent padding from an archive read
414 * from a socket or a pipe. This is to prevent the process on the
415 * other side of the pipe from getting a SIGPIPE (pax will stop
416 * reading an archive once a format dependent trailer is detected).
417 */
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418void
419ar_drain(void)
984263bc 420{
86a586bb 421 int res;
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422 char drbuf[MAXBLK];
423
424 /*
425 * we only drain from a pipe/socket. Other devices can be closed
426 * without reading up to end of file. We sure hope that pipe is closed
427 * on the other side so we will get an EOF.
428 */
429 if ((artyp != ISPIPE) || (lstrval <= 0))
430 return;
431
432 /*
433 * keep reading until pipe is drained
434 */
435 while ((res = read(arfd, drbuf, sizeof(drbuf))) > 0)
436 ;
437 lstrval = res;
438}
439
440/*
441 * ar_set_wr()
442 * Set up device right before switching from read to write in an append.
443 * device dependent code (if required) to do this should be added here.
444 * For all archive devices we are already positioned at the place we want
445 * to start writing when this routine is called.
446 * Return:
447 * 0 if all ready to write, -1 otherwise
448 */
449
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450int
451ar_set_wr(void)
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452{
453 off_t cpos;
454
455 /*
456 * we must make sure the trailer is rewritten on append, ar_next()
457 * will stop us if the archive containing the trailer was not written
458 */
459 wr_trail = 0;
460
461 /*
462 * Add any device dependent code as required here
463 */
464 if (artyp != ISREG)
465 return(0);
466 /*
467 * Ok we have an archive in a regular file. If we were rewriting a
468 * file, we must get rid of all the stuff after the current offset
469 * (it was not written by pax).
470 */
471 if (((cpos = lseek(arfd, (off_t)0L, SEEK_CUR)) < 0) ||
472 (ftruncate(arfd, cpos) < 0)) {
473 syswarn(1, errno, "Unable to truncate archive file");
474 return(-1);
475 }
476 return(0);
477}
478
479/*
480 * ar_app_ok()
481 * check if the last volume in the archive allows appends. We cannot check
482 * this until we are ready to write since there is no spec that says all
483 * volumes in a single archive have to be of the same type...
484 * Return:
485 * 0 if we can append, -1 otherwise.
486 */
487
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488int
489ar_app_ok(void)
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490{
491 if (artyp == ISPIPE) {
492 paxwarn(1, "Cannot append to an archive obtained from a pipe.");
493 return(-1);
494 }
495
496 if (!invld_rec)
497 return(0);
498 paxwarn(1,"Cannot append, device record size %d does not support %s spec",
499 rdblksz, argv0);
500 return(-1);
501}
502
503/*
504 * ar_read()
505 * read up to a specified number of bytes from the archive into the
506 * supplied buffer. When dealing with tapes we may not always be able to
507 * read what we want.
508 * Return:
509 * Number of bytes in buffer. 0 for end of file, -1 for a read error.
510 */
511
984263bc 512int
86a586bb 513ar_read(char *buf, int cnt)
984263bc 514{
86a586bb 515 int res = 0;
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516
517 /*
518 * if last i/o was in error, no more reads until reset or new volume
519 */
520 if (lstrval <= 0)
521 return(lstrval);
522
523 /*
524 * how we read must be based on device type
525 */
526 switch (artyp) {
527 case ISTAPE:
528 if ((res = read(arfd, buf, cnt)) > 0) {
529 /*
530 * CAUTION: tape systems may not always return the same
531 * sized records so we leave blksz == MAXBLK. The
532 * physical record size that a tape drive supports is
533 * very hard to determine in a uniform and portable
534 * manner.
535 */
536 io_ok = 1;
537 if (res != rdblksz) {
538 /*
539 * Record size changed. If this is happens on
540 * any record after the first, we probably have
541 * a tape drive which has a fixed record size
542 * we are getting multiple records in a single
543 * read). Watch out for record blocking that
544 * violates pax spec (must be a multiple of
545 * BLKMULT).
546 */
547 rdblksz = res;
548 if (rdblksz % BLKMULT)
549 invld_rec = 1;
550 }
551 return(res);
552 }
553 break;
554 case ISREG:
555 case ISBLK:
556 case ISCHR:
557 case ISPIPE:
558 default:
559 /*
560 * Files are so easy to deal with. These other things cannot
561 * be trusted at all. So when we are dealing with character
562 * devices and pipes we just take what they have ready for us
563 * and return. Trying to do anything else with them runs the
564 * risk of failure.
565 */
566 if ((res = read(arfd, buf, cnt)) > 0) {
567 io_ok = 1;
568 return(res);
569 }
570 break;
571 }
572
573 /*
574 * We are in trouble at this point, something is broken...
575 */
576 lstrval = res;
577 if (res < 0)
578 syswarn(1, errno, "Failed read on archive volume %d", arvol);
579 else
580 paxwarn(0, "End of archive volume %d reached", arvol);
581 return(res);
582}
583
584/*
585 * ar_write()
586 * Write a specified number of bytes in supplied buffer to the archive
587 * device so it appears as a single "block". Deals with errors and tries
588 * to recover when faced with short writes.
589 * Return:
590 * Number of bytes written. 0 indicates end of volume reached and with no
591 * flaws (as best that can be detected). A -1 indicates an unrecoverable
592 * error in the archive occured.
593 */
594
984263bc 595int
86a586bb 596ar_write(char *buf, int bsz)
984263bc 597{
86a586bb 598 int res;
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599 off_t cpos;
600
601 /*
602 * do not allow pax to create a "bad" archive. Once a write fails on
603 * an archive volume prevent further writes to it.
604 */
605 if (lstrval <= 0)
606 return(lstrval);
607
608 if ((res = write(arfd, buf, bsz)) == bsz) {
609 wr_trail = 1;
610 io_ok = 1;
611 return(bsz);
612 }
613 /*
614 * write broke, see what we can do with it. We try to send any partial
615 * writes that may violate pax spec to the next archive volume.
616 */
617 if (res < 0)
618 lstrval = res;
619 else
620 lstrval = 0;
621
622 switch (artyp) {
623 case ISREG:
624 if ((res > 0) && (res % BLKMULT)) {
625 /*
626 * try to fix up partial writes which are not BLKMULT
627 * in size by forcing the runt record to next archive
628 * volume
629 */
630 if ((cpos = lseek(arfd, (off_t)0L, SEEK_CUR)) < 0)
631 break;
632 cpos -= (off_t)res;
633 if (ftruncate(arfd, cpos) < 0)
634 break;
635 res = lstrval = 0;
636 break;
637 }
638 if (res >= 0)
639 break;
640 /*
641 * if file is out of space, handle it like a return of 0
642 */
643 if ((errno == ENOSPC) || (errno == EFBIG) || (errno == EDQUOT))
644 res = lstrval = 0;
645 break;
646 case ISTAPE:
647 case ISCHR:
648 case ISBLK:
649 if (res >= 0)
650 break;
651 if (errno == EACCES) {
652 paxwarn(0, "Write failed, archive is write protected.");
653 res = lstrval = 0;
654 return(0);
655 }
656 /*
657 * see if we reached the end of media, if so force a change to
658 * the next volume
659 */
660 if ((errno == ENOSPC) || (errno == EIO) || (errno == ENXIO))
661 res = lstrval = 0;
662 break;
663 case ISPIPE:
664 default:
665 /*
666 * we cannot fix errors to these devices
667 */
668 break;
669 }
670
671 /*
672 * Better tell the user the bad news...
673 * if this is a block aligned archive format, we may have a bad archive
674 * if the format wants the header to start at a BLKMULT boundary. While
675 * we can deal with the mis-aligned data, it violates spec and other
676 * archive readers will likely fail. if the format is not block
677 * aligned, the user may be lucky (and the archive is ok).
678 */
679 if (res >= 0) {
680 if (res > 0)
681 wr_trail = 1;
682 io_ok = 1;
683 }
684
685 /*
686 * If we were trying to rewrite the trailer and it didn't work, we
687 * must quit right away.
688 */
689 if (!wr_trail && (res <= 0)) {
690 paxwarn(1,"Unable to append, trailer re-write failed. Quitting.");
691 return(res);
692 }
693
694 if (res == 0)
695 paxwarn(0, "End of archive volume %d reached", arvol);
696 else if (res < 0)
697 syswarn(1, errno, "Failed write to archive volume: %d", arvol);
698 else if (!frmt->blkalgn || ((res % frmt->blkalgn) == 0))
699 paxwarn(0,"WARNING: partial archive write. Archive MAY BE FLAWED");
700 else
701 paxwarn(1,"WARNING: partial archive write. Archive IS FLAWED");
702 return(res);
703}
704
705/*
706 * ar_rdsync()
707 * Try to move past a bad spot on a flawed archive as needed to continue
708 * I/O. Clears error flags to allow I/O to continue.
709 * Return:
710 * 0 when ok to try i/o again, -1 otherwise.
711 */
712
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713int
714ar_rdsync(void)
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715{
716 long fsbz;
717 off_t cpos;
718 off_t mpos;
719 struct mtop mb;
720
721 /*
722 * Fail resync attempts at user request (done) or this is going to be
723 * an update/append to a existing archive. if last i/o hit media end,
724 * we need to go to the next volume not try a resync
725 */
726 if ((done > 0) || (lstrval == 0))
727 return(-1);
728
729 if ((act == APPND) || (act == ARCHIVE)) {
730 paxwarn(1, "Cannot allow updates to an archive with flaws.");
731 return(-1);
732 }
733 if (io_ok)
734 did_io = 1;
735
736 switch(artyp) {
737 case ISTAPE:
738 /*
739 * if the last i/o was a successful data transfer, we assume
740 * the fault is just a bad record on the tape that we are now
741 * past. If we did not get any data since the last resync try
742 * to move the tape forward one PHYSICAL record past any
743 * damaged tape section. Some tape drives are stubborn and need
744 * to be pushed.
745 */
746 if (io_ok) {
747 io_ok = 0;
748 lstrval = 1;
749 break;
750 }
751 mb.mt_op = MTFSR;
752 mb.mt_count = 1;
753 if (ioctl(arfd, MTIOCTOP, &mb) < 0)
754 break;
755 lstrval = 1;
756 break;
757 case ISREG:
758 case ISCHR:
759 case ISBLK:
760 /*
761 * try to step over the bad part of the device.
762 */
763 io_ok = 0;
764 if (((fsbz = arsb.st_blksize) <= 0) || (artyp != ISREG))
765 fsbz = BLKMULT;
766 if ((cpos = lseek(arfd, (off_t)0L, SEEK_CUR)) < 0)
767 break;
768 mpos = fsbz - (cpos % (off_t)fsbz);
769 if (lseek(arfd, mpos, SEEK_CUR) < 0)
770 break;
771 lstrval = 1;
772 break;
773 case ISPIPE:
774 default:
775 /*
776 * cannot recover on these archive device types
777 */
778 io_ok = 0;
779 break;
780 }
781 if (lstrval <= 0) {
782 paxwarn(1, "Unable to recover from an archive read failure.");
783 return(-1);
784 }
785 paxwarn(0, "Attempting to recover from an archive read failure.");
786 return(0);
787}
788
789/*
790 * ar_fow()
791 * Move the I/O position within the archive foward the specified number of
792 * bytes as supported by the device. If we cannot move the requested
793 * number of bytes, return the actual number of bytes moved in skipped.
794 * Return:
795 * 0 if moved the requested distance, -1 on complete failure, 1 on
796 * partial move (the amount moved is in skipped)
797 */
798
984263bc
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799int
800ar_fow(off_t sksz, off_t *skipped)
984263bc
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801{
802 off_t cpos;
803 off_t mpos;
804
805 *skipped = 0;
806 if (sksz <= 0)
807 return(0);
808
809 /*
810 * we cannot move foward at EOF or error
811 */
812 if (lstrval <= 0)
813 return(lstrval);
814
815 /*
816 * Safer to read forward on devices where it is hard to find the end of
817 * the media without reading to it. With tapes we cannot be sure of the
818 * number of physical blocks to skip (we do not know physical block
819 * size at this point), so we must only read foward on tapes!
820 */
821 if (artyp != ISREG)
822 return(0);
823
824 /*
825 * figure out where we are in the archive
826 */
827 if ((cpos = lseek(arfd, (off_t)0L, SEEK_CUR)) >= 0) {
828 /*
829 * we can be asked to move farther than there are bytes in this
830 * volume, if so, just go to file end and let normal buf_fill()
831 * deal with the end of file (it will go to next volume by
832 * itself)
833 */
834 if ((mpos = cpos + sksz) > arsb.st_size) {
835 *skipped = arsb.st_size - cpos;
836 mpos = arsb.st_size;
837 } else
838 *skipped = sksz;
839 if (lseek(arfd, mpos, SEEK_SET) >= 0)
840 return(0);
841 }
842 syswarn(1, errno, "Forward positioning operation on archive failed");
843 lstrval = -1;
844 return(-1);
845}
846
847/*
848 * ar_rev()
849 * move the i/o position within the archive backwards the specified byte
850 * count as supported by the device. With tapes drives we RESET rdblksz to
851 * the PHYSICAL blocksize.
852 * NOTE: We should only be called to move backwards so we can rewrite the
853 * last records (the trailer) of an archive (APPEND).
854 * Return:
855 * 0 if moved the requested distance, -1 on complete failure
856 */
857
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858int
859ar_rev(off_t sksz)
984263bc
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860{
861 off_t cpos;
862 struct mtop mb;
86a586bb 863 int phyblk;
984263bc
MD
864
865 /*
866 * make sure we do not have try to reverse on a flawed archive
867 */
868 if (lstrval < 0)
869 return(lstrval);
870
871 switch(artyp) {
872 case ISPIPE:
873 if (sksz <= 0)
874 break;
875 /*
876 * cannot go backwards on these critters
877 */
878 paxwarn(1, "Reverse positioning on pipes is not supported.");
879 lstrval = -1;
880 return(-1);
881 case ISREG:
882 case ISBLK:
883 case ISCHR:
884 default:
885 if (sksz <= 0)
886 break;
887
888 /*
889 * For things other than files, backwards movement has a very
890 * high probability of failure as we really do not know the
891 * true attributes of the device we are talking to (the device
892 * may not even have the ability to lseek() in any direction).
893 * First we figure out where we are in the archive.
894 */
895 if ((cpos = lseek(arfd, (off_t)0L, SEEK_CUR)) < 0) {
896 syswarn(1, errno,
897 "Unable to obtain current archive byte offset");
898 lstrval = -1;
899 return(-1);
900 }
901
902 /*
903 * we may try to go backwards past the start when the archive
904 * is only a single record. If this hapens and we are on a
905 * multi volume archive, we need to go to the end of the
906 * previous volume and continue our movement backwards from
907 * there.
908 */
909 if ((cpos -= sksz) < (off_t)0L) {
910 if (arvol > 1) {
911 /*
912 * this should never happen
913 */
914 paxwarn(1,"Reverse position on previous volume.");
915 lstrval = -1;
916 return(-1);
917 }
918 cpos = (off_t)0L;
919 }
920 if (lseek(arfd, cpos, SEEK_SET) < 0) {
921 syswarn(1, errno, "Unable to seek archive backwards");
922 lstrval = -1;
923 return(-1);
924 }
925 break;
926 case ISTAPE:
927 /*
928 * Calculate and move the proper number of PHYSICAL tape
929 * blocks. If the sksz is not an even multiple of the physical
930 * tape size, we cannot do the move (this should never happen).
931 * (We also cannot handler trailers spread over two vols).
932 * get_phys() also makes sure we are in front of the filemark.
933 */
934 if ((phyblk = get_phys()) <= 0) {
935 lstrval = -1;
936 return(-1);
937 }
938
939 /*
940 * make sure future tape reads only go by physical tape block
941 * size (set rdblksz to the real size).
942 */
943 rdblksz = phyblk;
944
945 /*
946 * if no movement is required, just return (we must be after
947 * get_phys() so the physical blocksize is properly set)
948 */
949 if (sksz <= 0)
950 break;
951
952 /*
953 * ok we have to move. Make sure the tape drive can do it.
954 */
955 if (sksz % phyblk) {
956 paxwarn(1,
957 "Tape drive unable to backspace requested amount");
958 lstrval = -1;
959 return(-1);
960 }
961
962 /*
963 * move backwards the requested number of bytes
964 */
965 mb.mt_op = MTBSR;
966 mb.mt_count = sksz/phyblk;
967 if (ioctl(arfd, MTIOCTOP, &mb) < 0) {
968 syswarn(1,errno, "Unable to backspace tape %d blocks.",
969 mb.mt_count);
970 lstrval = -1;
971 return(-1);
972 }
973 break;
974 }
975 lstrval = 1;
976 return(0);
977}
978
979/*
980 * get_phys()
981 * Determine the physical block size on a tape drive. We need the physical
982 * block size so we know how many bytes we skip over when we move with
983 * mtio commands. We also make sure we are BEFORE THE TAPE FILEMARK when
984 * return.
985 * This is one really SLOW routine...
986 * Return:
987 * physical block size if ok (ok > 0), -1 otherwise
988 */
989
984263bc
MD
990static int
991get_phys(void)
984263bc 992{
86a586bb
LF
993 int padsz = 0;
994 int res;
995 int phyblk;
984263bc
MD
996 struct mtop mb;
997 char scbuf[MAXBLK];
998
999 /*
1000 * move to the file mark, and then back up one record and read it.
1001 * this should tell us the physical record size the tape is using.
1002 */
1003 if (lstrval == 1) {
1004 /*
1005 * we know we are at file mark when we get back a 0 from
1006 * read()
1007 */
1008 while ((res = read(arfd, scbuf, sizeof(scbuf))) > 0)
1009 padsz += res;
1010 if (res < 0) {
1011 syswarn(1, errno, "Unable to locate tape filemark.");
1012 return(-1);
1013 }
1014 }
1015
1016 /*
1017 * move backwards over the file mark so we are at the end of the
1018 * last record.
1019 */
1020 mb.mt_op = MTBSF;
1021 mb.mt_count = 1;
1022 if (ioctl(arfd, MTIOCTOP, &mb) < 0) {
1023 syswarn(1, errno, "Unable to backspace over tape filemark.");
1024 return(-1);
1025 }
1026
1027 /*
1028 * move backwards so we are in front of the last record and read it to
1029 * get physical tape blocksize.
1030 */
1031 mb.mt_op = MTBSR;
1032 mb.mt_count = 1;
1033 if (ioctl(arfd, MTIOCTOP, &mb) < 0) {
1034 syswarn(1, errno, "Unable to backspace over last tape block.");
1035 return(-1);
1036 }
1037 if ((phyblk = read(arfd, scbuf, sizeof(scbuf))) <= 0) {
1038 syswarn(1, errno, "Cannot determine archive tape blocksize.");
1039 return(-1);
1040 }
1041
1042 /*
1043 * read foward to the file mark, then back up in front of the filemark
1044 * (this is a bit paranoid, but should be safe to do).
1045 */
1046 while ((res = read(arfd, scbuf, sizeof(scbuf))) > 0)
1047 ;
1048 if (res < 0) {
1049 syswarn(1, errno, "Unable to locate tape filemark.");
1050 return(-1);
1051 }
1052 mb.mt_op = MTBSF;
1053 mb.mt_count = 1;
1054 if (ioctl(arfd, MTIOCTOP, &mb) < 0) {
1055 syswarn(1, errno, "Unable to backspace over tape filemark.");
1056 return(-1);
1057 }
1058
1059 /*
1060 * set lstrval so we know that the filemark has not been seen
1061 */
1062 lstrval = 1;
1063
1064 /*
1065 * return if there was no padding
1066 */
1067 if (padsz == 0)
1068 return(phyblk);
1069
1070 /*
1071 * make sure we can move backwards over the padding. (this should
1072 * never fail).
1073 */
1074 if (padsz % phyblk) {
1075 paxwarn(1, "Tape drive unable to backspace requested amount");
1076 return(-1);
1077 }
1078
1079 /*
1080 * move backwards over the padding so the head is where it was when
1081 * we were first called (if required).
1082 */
1083 mb.mt_op = MTBSR;
1084 mb.mt_count = padsz/phyblk;
1085 if (ioctl(arfd, MTIOCTOP, &mb) < 0) {
1086 syswarn(1,errno,"Unable to backspace tape over %d pad blocks",
1087 mb.mt_count);
1088 return(-1);
1089 }
1090 return(phyblk);
1091}
1092
1093/*
1094 * ar_next()
1095 * prompts the user for the next volume in this archive. For some devices
1096 * we may allow the media to be changed. Otherwise a new archive is
1097 * prompted for. By pax spec, if there is no controlling tty or an eof is
1098 * read on tty input, we must quit pax.
1099 * Return:
1100 * 0 when ready to continue, -1 when all done
1101 */
1102
984263bc
MD
1103int
1104ar_next(void)
984263bc
MD
1105{
1106 char buf[PAXPATHLEN+2];
1107 static int freeit = 0;
1108 sigset_t o_mask;
1109
1110 /*
1111 * WE MUST CLOSE THE DEVICE. A lot of devices must see last close, (so
1112 * things like writing EOF etc will be done) (Watch out ar_close() can
1113 * also be called via a signal handler, so we must prevent a race.
1114 */
1115 if (sigprocmask(SIG_BLOCK, &s_mask, &o_mask) < 0)
1116 syswarn(0, errno, "Unable to set signal mask");
1117 ar_close();
1118 if (sigprocmask(SIG_SETMASK, &o_mask, NULL) < 0)
1119 syswarn(0, errno, "Unable to restore signal mask");
1120
1121 if (done || !wr_trail || strcmp(NM_TAR, argv0) == 0)
1122 return(-1);
1123
1124 tty_prnt("\nATTENTION! %s archive volume change required.\n", argv0);
1125
1126 /*
1127 * if i/o is on stdin or stdout, we cannot reopen it (we do not know
1128 * the name), the user will be forced to type it in.
1129 */
1130 if (strcmp(arcname, STDO) && strcmp(arcname, STDN) && (artyp != ISREG)
1131 && (artyp != ISPIPE)) {
1132 if (artyp == ISTAPE) {
1133 tty_prnt("%s ready for archive tape volume: %d\n",
1134 arcname, arvol);
1135 tty_prnt("Load the NEXT TAPE on the tape drive");
1136 } else {
1137 tty_prnt("%s ready for archive volume: %d\n",
1138 arcname, arvol);
1139 tty_prnt("Load the NEXT STORAGE MEDIA (if required)");
1140 }
1141
1142 if ((act == ARCHIVE) || (act == APPND))
1143 tty_prnt(" and make sure it is WRITE ENABLED.\n");
1144 else
1145 tty_prnt("\n");
1146
1147 for(;;) {
1148 tty_prnt("Type \"y\" to continue, \".\" to quit %s,",
1149 argv0);
1150 tty_prnt(" or \"s\" to switch to new device.\nIf you");
1151 tty_prnt(" cannot change storage media, type \"s\"\n");
1152 tty_prnt("Is the device ready and online? > ");
1153
1154 if ((tty_read(buf,sizeof(buf))<0) || !strcmp(buf,".")){
1155 done = 1;
1156 lstrval = -1;
1157 tty_prnt("Quitting %s!\n", argv0);
1158 vfpart = 0;
1159 return(-1);
1160 }
1161
1162 if ((buf[0] == '\0') || (buf[1] != '\0')) {
1163 tty_prnt("%s unknown command, try again\n",buf);
1164 continue;
1165 }
1166
1167 switch (buf[0]) {
1168 case 'y':
1169 case 'Y':
1170 /*
1171 * we are to continue with the same device
1172 */
1173 if (ar_open(arcname) >= 0)
1174 return(0);
1175 tty_prnt("Cannot re-open %s, try again\n",
1176 arcname);
1177 continue;
1178 case 's':
1179 case 'S':
1180 /*
1181 * user wants to open a different device
1182 */
1183 tty_prnt("Switching to a different archive\n");
1184 break;
1185 default:
1186 tty_prnt("%s unknown command, try again\n",buf);
1187 continue;
1188 }
1189 break;
1190 }
1191 } else
1192 tty_prnt("Ready for archive volume: %d\n", arvol);
1193
1194 /*
1195 * have to go to a different archive
1196 */
1197 for (;;) {
1198 tty_prnt("Input archive name or \".\" to quit %s.\n", argv0);
1199 tty_prnt("Archive name > ");
1200
1201 if ((tty_read(buf, sizeof(buf)) < 0) || !strcmp(buf, ".")) {
1202 done = 1;
1203 lstrval = -1;
1204 tty_prnt("Quitting %s!\n", argv0);
1205 vfpart = 0;
1206 return(-1);
1207 }
1208 if (buf[0] == '\0') {
1209 tty_prnt("Empty file name, try again\n");
1210 continue;
1211 }
1212 if (!strcmp(buf, "..")) {
1213 tty_prnt("Illegal file name: .. try again\n");
1214 continue;
1215 }
1216 if (strlen(buf) > PAXPATHLEN) {
1217 tty_prnt("File name too long, try again\n");
1218 continue;
1219 }
1220
1221 /*
1222 * try to open new archive
1223 */
1224 if (ar_open(buf) >= 0) {
1225 if (freeit) {
57fed2af 1226 free(arcname);
984263bc
MD
1227 freeit = 0;
1228 }
1229 if ((arcname = strdup(buf)) == NULL) {
1230 done = 1;
1231 lstrval = -1;
1232 paxwarn(0, "Cannot save archive name.");
1233 return(-1);
1234 }
1235 freeit = 1;
1236 break;
1237 }
1238 tty_prnt("Cannot open %s, try again\n", buf);
1239 continue;
1240 }
1241 return(0);
1242}
1243
1244/*
1245 * ar_start_gzip()
1246 * starts the gzip compression/decompression process as a child, using magic
1247 * to keep the fd the same in the calling function (parent).
1248 */
1249void
1250ar_start_gzip(int fd, const char *gzip_program, int wr)
1251{
1252 int fds[2];
1253 char *gzip_flags;
1254
1255 if (pipe(fds) < 0)
1256 err(1, "could not pipe");
1257 zpid = fork();
1258 if (zpid < 0)
1259 err(1, "could not fork");
1260
1261 /* parent */
1262 if (zpid) {
1263 if (wr)
1264 dup2(fds[1], fd);
1265 else
1266 dup2(fds[0], fd);
1267 close(fds[0]);
1268 close(fds[1]);
1269 } else {
1270 if (wr) {
1271 dup2(fds[0], STDIN_FILENO);
1272 dup2(fd, STDOUT_FILENO);
1273 gzip_flags = "-c";
1274 } else {
1275 dup2(fds[1], STDOUT_FILENO);
1276 dup2(fd, STDIN_FILENO);
1277 gzip_flags = "-dc";
1278 }
1279 close(fds[0]);
1280 close(fds[1]);
1281 if (execlp(gzip_program, gzip_program, gzip_flags,
1282 (char *)NULL) < 0)
1283 err(1, "could not exec");
1284 /* NOTREACHED */
1285 }
1286}