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. 36 */ 37 38 #ifndef lint 39 #if 0 40 static char sccsid[] = "@(#)ar_io.c 8.2 (Berkeley) 4/18/94"; 41 #endif 42 static const char rcsid[] = 43 "$FreeBSD: src/bin/pax/ar_io.c,v 1.12.2.1 2001/08/01 05:03:11 obrien Exp $"; 44 #endif /* not lint */ 45 46 #include <sys/types.h> 47 #include <sys/ioctl.h> 48 #include <sys/mtio.h> 49 #include <sys/stat.h> 50 #include <sys/wait.h> 51 #include <err.h> 52 #include <errno.h> 53 #include <fcntl.h> 54 #include <signal.h> 55 #include <stdio.h> 56 #include <string.h> 57 #include <stdlib.h> 58 #include <unistd.h> 59 #include "pax.h" 60 #include "options.h" 61 #include "extern.h" 62 63 /* 64 * Routines which deal directly with the archive I/O device/file. 65 */ 66 67 #define DMOD 0666 /* default mode of created archives */ 68 #define EXT_MODE O_RDONLY /* open mode for list/extract */ 69 #define AR_MODE (O_WRONLY | O_CREAT | O_TRUNC) /* mode for archive */ 70 #define APP_MODE O_RDWR /* mode for append */ 71 #define STDO "<STDOUT>" /* pseudo name for stdout */ 72 #define STDN "<STDIN>" /* pseudo name for stdin */ 73 static int arfd = -1; /* archive file descriptor */ 74 static int artyp = ISREG; /* archive type: file/FIFO/tape */ 75 static int arvol = 1; /* archive volume number */ 76 static int lstrval = -1; /* return value from last i/o */ 77 static int io_ok; /* i/o worked on volume after resync */ 78 static int did_io; /* did i/o ever occur on volume? */ 79 static int done; /* set via tty termination */ 80 static struct stat arsb; /* stat of archive device at open */ 81 static int invld_rec; /* tape has out of spec record size */ 82 static int wr_trail = 1; /* trailer was rewritten in append */ 83 static int can_unlnk = 0; /* do we unlink null archives? */ 84 char *arcname; /* printable name of archive */ 85 const char *gzip_program; /* name of gzip program */ 86 static pid_t zpid = -1; /* pid of child process */ 87 88 static int get_phys __P((void)); 89 extern sigset_t s_mask; 90 static void ar_start_gzip __P((int, const char *, int)); 91 92 /* 93 * ar_open() 94 * Opens the next archive volume. Determines the type of the device and 95 * sets up block sizes as required by the archive device and the format. 96 * Note: we may be called with name == NULL on the first open only. 97 * Return: 98 * -1 on failure, 0 otherwise 99 */ 100 101 #ifdef __STDC__ 102 int 103 ar_open(char *name) 104 #else 105 int 106 ar_open(name) 107 char *name; 108 #endif 109 { 110 struct mtget mb; 111 112 if (arfd != -1) 113 (void)close(arfd); 114 arfd = -1; 115 can_unlnk = did_io = io_ok = invld_rec = 0; 116 artyp = ISREG; 117 flcnt = 0; 118 119 /* 120 * open based on overall operation mode 121 */ 122 switch (act) { 123 case LIST: 124 case EXTRACT: 125 if (name == NULL) { 126 arfd = STDIN_FILENO; 127 arcname = STDN; 128 } else if ((arfd = open(name, EXT_MODE, DMOD)) < 0) 129 syswarn(0, errno, "Failed open to read on %s", name); 130 if (arfd != -1 && gzip_program != NULL) 131 ar_start_gzip(arfd, gzip_program, 0); 132 break; 133 case ARCHIVE: 134 if (name == NULL) { 135 arfd = STDOUT_FILENO; 136 arcname = STDO; 137 } else if ((arfd = open(name, AR_MODE, DMOD)) < 0) 138 syswarn(0, errno, "Failed open to write on %s", name); 139 else 140 can_unlnk = 1; 141 if (arfd != -1 && gzip_program != NULL) 142 ar_start_gzip(arfd, gzip_program, 1); 143 break; 144 case APPND: 145 if (name == NULL) { 146 arfd = STDOUT_FILENO; 147 arcname = STDO; 148 } else if ((arfd = open(name, APP_MODE, DMOD)) < 0) 149 syswarn(0, errno, "Failed open to read/write on %s", 150 name); 151 break; 152 case COPY: 153 /* 154 * arfd not used in COPY mode 155 */ 156 arcname = "<NONE>"; 157 lstrval = 1; 158 return(0); 159 } 160 if (arfd < 0) 161 return(-1); 162 163 if (chdname != NULL) 164 if (chdir(chdname) != 0) 165 syswarn(1, errno, "Failed chdir to %s", chdname); 166 /* 167 * set up is based on device type 168 */ 169 if (fstat(arfd, &arsb) < 0) { 170 syswarn(0, errno, "Failed stat on %s", arcname); 171 (void)close(arfd); 172 arfd = -1; 173 can_unlnk = 0; 174 return(-1); 175 } 176 if (S_ISDIR(arsb.st_mode)) { 177 paxwarn(0, "Cannot write an archive on top of a directory %s", 178 arcname); 179 (void)close(arfd); 180 arfd = -1; 181 can_unlnk = 0; 182 return(-1); 183 } 184 185 if (S_ISCHR(arsb.st_mode)) 186 artyp = ioctl(arfd, MTIOCGET, &mb) ? ISCHR : ISTAPE; 187 else if (S_ISBLK(arsb.st_mode)) 188 artyp = ISBLK; 189 else if ((lseek(arfd, (off_t)0L, SEEK_CUR) == -1) && (errno == ESPIPE)) 190 artyp = ISPIPE; 191 else 192 artyp = ISREG; 193 194 /* 195 * make sure we beyond any doubt that we only can unlink regular files 196 * we created 197 */ 198 if (artyp != ISREG) 199 can_unlnk = 0; 200 /* 201 * if we are writing, we are done 202 */ 203 if (act == ARCHIVE) { 204 blksz = rdblksz = wrblksz; 205 lstrval = 1; 206 return(0); 207 } 208 209 /* 210 * set default blksz on read. APPNDs writes rdblksz on the last volume 211 * On all new archive volumes, we shift to wrblksz (if the user 212 * specified one, otherwize we will continue to use rdblksz). We 213 * must to set blocksize based on what kind of device the archive is 214 * stored. 215 */ 216 switch(artyp) { 217 case ISTAPE: 218 /* 219 * Tape drives come in at least two flavors. Those that support 220 * variable sized records and those that have fixed sized 221 * records. They must be treated differently. For tape drives 222 * that support variable sized records, we must make large 223 * reads to make sure we get the entire record, otherwise we 224 * will just get the first part of the record (up to size we 225 * asked). Tapes with fixed sized records may or may not return 226 * multiple records in a single read. We really do not care 227 * what the physical record size is UNLESS we are going to 228 * append. (We will need the physical block size to rewrite 229 * the trailer). Only when we are appending do we go to the 230 * effort to figure out the true PHYSICAL record size. 231 */ 232 blksz = rdblksz = MAXBLK; 233 break; 234 case ISPIPE: 235 case ISBLK: 236 case ISCHR: 237 /* 238 * Blocksize is not a major issue with these devices (but must 239 * be kept a multiple of 512). If the user specified a write 240 * block size, we use that to read. Under append, we must 241 * always keep blksz == rdblksz. Otherwise we go ahead and use 242 * the device optimal blocksize as (and if) returned by stat 243 * and if it is within pax specs. 244 */ 245 if ((act == APPND) && wrblksz) { 246 blksz = rdblksz = wrblksz; 247 break; 248 } 249 250 if ((arsb.st_blksize > 0) && (arsb.st_blksize < MAXBLK) && 251 ((arsb.st_blksize % BLKMULT) == 0)) 252 rdblksz = arsb.st_blksize; 253 else 254 rdblksz = DEVBLK; 255 /* 256 * For performance go for large reads when we can without harm 257 */ 258 if ((act == APPND) || (artyp == ISCHR)) 259 blksz = rdblksz; 260 else 261 blksz = MAXBLK; 262 break; 263 case ISREG: 264 /* 265 * if the user specified wrblksz works, use it. Under appends 266 * we must always keep blksz == rdblksz 267 */ 268 if ((act == APPND) && wrblksz && ((arsb.st_size%wrblksz)==0)){ 269 blksz = rdblksz = wrblksz; 270 break; 271 } 272 /* 273 * See if we can find the blocking factor from the file size 274 */ 275 for (rdblksz = MAXBLK; rdblksz > 0; rdblksz -= BLKMULT) 276 if ((arsb.st_size % rdblksz) == 0) 277 break; 278 /* 279 * When we cannot find a match, we may have a flawed archive. 280 */ 281 if (rdblksz <= 0) 282 rdblksz = FILEBLK; 283 /* 284 * for performance go for large reads when we can 285 */ 286 if (act == APPND) 287 blksz = rdblksz; 288 else 289 blksz = MAXBLK; 290 break; 291 default: 292 /* 293 * should never happen, worse case, slow... 294 */ 295 blksz = rdblksz = BLKMULT; 296 break; 297 } 298 lstrval = 1; 299 return(0); 300 } 301 302 /* 303 * ar_close() 304 * closes archive device, increments volume number, and prints i/o summary 305 */ 306 #ifdef __STDC__ 307 void 308 ar_close(void) 309 #else 310 void 311 ar_close() 312 #endif 313 { 314 315 if (arfd < 0) { 316 did_io = io_ok = flcnt = 0; 317 return; 318 } 319 320 /* 321 * Close archive file. This may take a LONG while on tapes (we may be 322 * forced to wait for the rewind to complete) so tell the user what is 323 * going on (this avoids the user hitting control-c thinking pax is 324 * broken). 325 */ 326 if (vflag && (artyp == ISTAPE)) { 327 if (vfpart) 328 (void)putc('\n', listf); 329 (void)fprintf(listf, 330 "%s: Waiting for tape drive close to complete...", 331 argv0); 332 (void)fflush(listf); 333 } 334 335 /* 336 * if nothing was written to the archive (and we created it), we remove 337 * it 338 */ 339 if (can_unlnk && (fstat(arfd, &arsb) == 0) && (S_ISREG(arsb.st_mode)) && 340 (arsb.st_size == 0)) { 341 (void)unlink(arcname); 342 can_unlnk = 0; 343 } 344 345 /* 346 * for a quick extract/list, pax frequently exits before the child 347 * process is done 348 */ 349 if ((act == LIST || act == EXTRACT) && nflag && zpid > 0) { 350 int status; 351 kill(zpid, SIGINT); 352 waitpid(zpid, &status, 0); 353 } 354 355 (void)close(arfd); 356 357 if (vflag && (artyp == ISTAPE)) { 358 (void)fputs("done.\n", listf); 359 vfpart = 0; 360 (void)fflush(listf); 361 } 362 arfd = -1; 363 364 if (!io_ok && !did_io) { 365 flcnt = 0; 366 return; 367 } 368 did_io = io_ok = 0; 369 370 /* 371 * The volume number is only increased when the last device has data 372 * and we have already determined the archive format. 373 */ 374 if (frmt != NULL) 375 ++arvol; 376 377 if (!vflag) { 378 flcnt = 0; 379 return; 380 } 381 382 /* 383 * Print out a summary of I/O for this archive volume. 384 */ 385 if (vfpart) { 386 (void)putc('\n', listf); 387 vfpart = 0; 388 } 389 390 /* 391 * If we have not determined the format yet, we just say how many bytes 392 * we have skipped over looking for a header to id. there is no way we 393 * could have written anything yet. 394 */ 395 if (frmt == NULL) { 396 # ifdef NET2_STAT 397 (void)fprintf(listf, "%s: unknown format, %lu bytes skipped.\n", 398 # else 399 (void)fprintf(listf, "%s: unknown format, %qu bytes skipped.\n", 400 # endif 401 argv0, rdcnt); 402 (void)fflush(listf); 403 flcnt = 0; 404 return; 405 } 406 407 if (strcmp(NM_CPIO, argv0) == 0) 408 (void)fprintf(listf, "%qu blocks\n", (rdcnt ? rdcnt : wrcnt) / 5120); 409 else if (strcmp(NM_TAR, argv0) != 0) 410 (void)fprintf(listf, 411 # ifdef NET2_STAT 412 "%s: %s vol %d, %lu files, %lu bytes read, %lu bytes written.\n", 413 # else 414 "%s: %s vol %d, %lu files, %qu bytes read, %qu bytes written.\n", 415 # endif 416 argv0, frmt->name, arvol-1, flcnt, rdcnt, wrcnt); 417 (void)fflush(listf); 418 flcnt = 0; 419 } 420 421 /* 422 * ar_drain() 423 * drain any archive format independent padding from an archive read 424 * from a socket or a pipe. This is to prevent the process on the 425 * other side of the pipe from getting a SIGPIPE (pax will stop 426 * reading an archive once a format dependent trailer is detected). 427 */ 428 #ifdef __STDC__ 429 void 430 ar_drain(void) 431 #else 432 void 433 ar_drain() 434 #endif 435 { 436 register int res; 437 char drbuf[MAXBLK]; 438 439 /* 440 * we only drain from a pipe/socket. Other devices can be closed 441 * without reading up to end of file. We sure hope that pipe is closed 442 * on the other side so we will get an EOF. 443 */ 444 if ((artyp != ISPIPE) || (lstrval <= 0)) 445 return; 446 447 /* 448 * keep reading until pipe is drained 449 */ 450 while ((res = read(arfd, drbuf, sizeof(drbuf))) > 0) 451 ; 452 lstrval = res; 453 } 454 455 /* 456 * ar_set_wr() 457 * Set up device right before switching from read to write in an append. 458 * device dependent code (if required) to do this should be added here. 459 * For all archive devices we are already positioned at the place we want 460 * to start writing when this routine is called. 461 * Return: 462 * 0 if all ready to write, -1 otherwise 463 */ 464 465 #ifdef __STDC__ 466 int 467 ar_set_wr(void) 468 #else 469 int 470 ar_set_wr() 471 #endif 472 { 473 off_t cpos; 474 475 /* 476 * we must make sure the trailer is rewritten on append, ar_next() 477 * will stop us if the archive containing the trailer was not written 478 */ 479 wr_trail = 0; 480 481 /* 482 * Add any device dependent code as required here 483 */ 484 if (artyp != ISREG) 485 return(0); 486 /* 487 * Ok we have an archive in a regular file. If we were rewriting a 488 * file, we must get rid of all the stuff after the current offset 489 * (it was not written by pax). 490 */ 491 if (((cpos = lseek(arfd, (off_t)0L, SEEK_CUR)) < 0) || 492 (ftruncate(arfd, cpos) < 0)) { 493 syswarn(1, errno, "Unable to truncate archive file"); 494 return(-1); 495 } 496 return(0); 497 } 498 499 /* 500 * ar_app_ok() 501 * check if the last volume in the archive allows appends. We cannot check 502 * this until we are ready to write since there is no spec that says all 503 * volumes in a single archive have to be of the same type... 504 * Return: 505 * 0 if we can append, -1 otherwise. 506 */ 507 508 #ifdef __STDC__ 509 int 510 ar_app_ok(void) 511 #else 512 int 513 ar_app_ok() 514 #endif 515 { 516 if (artyp == ISPIPE) { 517 paxwarn(1, "Cannot append to an archive obtained from a pipe."); 518 return(-1); 519 } 520 521 if (!invld_rec) 522 return(0); 523 paxwarn(1,"Cannot append, device record size %d does not support %s spec", 524 rdblksz, argv0); 525 return(-1); 526 } 527 528 /* 529 * ar_read() 530 * read up to a specified number of bytes from the archive into the 531 * supplied buffer. When dealing with tapes we may not always be able to 532 * read what we want. 533 * Return: 534 * Number of bytes in buffer. 0 for end of file, -1 for a read error. 535 */ 536 537 #ifdef __STDC__ 538 int 539 ar_read(register char *buf, register int cnt) 540 #else 541 int 542 ar_read(buf, cnt) 543 register char *buf; 544 register int cnt; 545 #endif 546 { 547 register int res = 0; 548 549 /* 550 * if last i/o was in error, no more reads until reset or new volume 551 */ 552 if (lstrval <= 0) 553 return(lstrval); 554 555 /* 556 * how we read must be based on device type 557 */ 558 switch (artyp) { 559 case ISTAPE: 560 if ((res = read(arfd, buf, cnt)) > 0) { 561 /* 562 * CAUTION: tape systems may not always return the same 563 * sized records so we leave blksz == MAXBLK. The 564 * physical record size that a tape drive supports is 565 * very hard to determine in a uniform and portable 566 * manner. 567 */ 568 io_ok = 1; 569 if (res != rdblksz) { 570 /* 571 * Record size changed. If this is happens on 572 * any record after the first, we probably have 573 * a tape drive which has a fixed record size 574 * we are getting multiple records in a single 575 * read). Watch out for record blocking that 576 * violates pax spec (must be a multiple of 577 * BLKMULT). 578 */ 579 rdblksz = res; 580 if (rdblksz % BLKMULT) 581 invld_rec = 1; 582 } 583 return(res); 584 } 585 break; 586 case ISREG: 587 case ISBLK: 588 case ISCHR: 589 case ISPIPE: 590 default: 591 /* 592 * Files are so easy to deal with. These other things cannot 593 * be trusted at all. So when we are dealing with character 594 * devices and pipes we just take what they have ready for us 595 * and return. Trying to do anything else with them runs the 596 * risk of failure. 597 */ 598 if ((res = read(arfd, buf, cnt)) > 0) { 599 io_ok = 1; 600 return(res); 601 } 602 break; 603 } 604 605 /* 606 * We are in trouble at this point, something is broken... 607 */ 608 lstrval = res; 609 if (res < 0) 610 syswarn(1, errno, "Failed read on archive volume %d", arvol); 611 else 612 paxwarn(0, "End of archive volume %d reached", arvol); 613 return(res); 614 } 615 616 /* 617 * ar_write() 618 * Write a specified number of bytes in supplied buffer to the archive 619 * device so it appears as a single "block". Deals with errors and tries 620 * to recover when faced with short writes. 621 * Return: 622 * Number of bytes written. 0 indicates end of volume reached and with no 623 * flaws (as best that can be detected). A -1 indicates an unrecoverable 624 * error in the archive occured. 625 */ 626 627 #ifdef __STDC__ 628 int 629 ar_write(register char *buf, register int bsz) 630 #else 631 int 632 ar_write(buf, bsz) 633 register char *buf; 634 register int bsz; 635 #endif 636 { 637 register int res; 638 off_t cpos; 639 640 /* 641 * do not allow pax to create a "bad" archive. Once a write fails on 642 * an archive volume prevent further writes to it. 643 */ 644 if (lstrval <= 0) 645 return(lstrval); 646 647 if ((res = write(arfd, buf, bsz)) == bsz) { 648 wr_trail = 1; 649 io_ok = 1; 650 return(bsz); 651 } 652 /* 653 * write broke, see what we can do with it. We try to send any partial 654 * writes that may violate pax spec to the next archive volume. 655 */ 656 if (res < 0) 657 lstrval = res; 658 else 659 lstrval = 0; 660 661 switch (artyp) { 662 case ISREG: 663 if ((res > 0) && (res % BLKMULT)) { 664 /* 665 * try to fix up partial writes which are not BLKMULT 666 * in size by forcing the runt record to next archive 667 * volume 668 */ 669 if ((cpos = lseek(arfd, (off_t)0L, SEEK_CUR)) < 0) 670 break; 671 cpos -= (off_t)res; 672 if (ftruncate(arfd, cpos) < 0) 673 break; 674 res = lstrval = 0; 675 break; 676 } 677 if (res >= 0) 678 break; 679 /* 680 * if file is out of space, handle it like a return of 0 681 */ 682 if ((errno == ENOSPC) || (errno == EFBIG) || (errno == EDQUOT)) 683 res = lstrval = 0; 684 break; 685 case ISTAPE: 686 case ISCHR: 687 case ISBLK: 688 if (res >= 0) 689 break; 690 if (errno == EACCES) { 691 paxwarn(0, "Write failed, archive is write protected."); 692 res = lstrval = 0; 693 return(0); 694 } 695 /* 696 * see if we reached the end of media, if so force a change to 697 * the next volume 698 */ 699 if ((errno == ENOSPC) || (errno == EIO) || (errno == ENXIO)) 700 res = lstrval = 0; 701 break; 702 case ISPIPE: 703 default: 704 /* 705 * we cannot fix errors to these devices 706 */ 707 break; 708 } 709 710 /* 711 * Better tell the user the bad news... 712 * if this is a block aligned archive format, we may have a bad archive 713 * if the format wants the header to start at a BLKMULT boundary. While 714 * we can deal with the mis-aligned data, it violates spec and other 715 * archive readers will likely fail. if the format is not block 716 * aligned, the user may be lucky (and the archive is ok). 717 */ 718 if (res >= 0) { 719 if (res > 0) 720 wr_trail = 1; 721 io_ok = 1; 722 } 723 724 /* 725 * If we were trying to rewrite the trailer and it didn't work, we 726 * must quit right away. 727 */ 728 if (!wr_trail && (res <= 0)) { 729 paxwarn(1,"Unable to append, trailer re-write failed. Quitting."); 730 return(res); 731 } 732 733 if (res == 0) 734 paxwarn(0, "End of archive volume %d reached", arvol); 735 else if (res < 0) 736 syswarn(1, errno, "Failed write to archive volume: %d", arvol); 737 else if (!frmt->blkalgn || ((res % frmt->blkalgn) == 0)) 738 paxwarn(0,"WARNING: partial archive write. Archive MAY BE FLAWED"); 739 else 740 paxwarn(1,"WARNING: partial archive write. Archive IS FLAWED"); 741 return(res); 742 } 743 744 /* 745 * ar_rdsync() 746 * Try to move past a bad spot on a flawed archive as needed to continue 747 * I/O. Clears error flags to allow I/O to continue. 748 * Return: 749 * 0 when ok to try i/o again, -1 otherwise. 750 */ 751 752 #ifdef __STDC__ 753 int 754 ar_rdsync(void) 755 #else 756 int 757 ar_rdsync() 758 #endif 759 { 760 long fsbz; 761 off_t cpos; 762 off_t mpos; 763 struct mtop mb; 764 765 /* 766 * Fail resync attempts at user request (done) or this is going to be 767 * an update/append to a existing archive. if last i/o hit media end, 768 * we need to go to the next volume not try a resync 769 */ 770 if ((done > 0) || (lstrval == 0)) 771 return(-1); 772 773 if ((act == APPND) || (act == ARCHIVE)) { 774 paxwarn(1, "Cannot allow updates to an archive with flaws."); 775 return(-1); 776 } 777 if (io_ok) 778 did_io = 1; 779 780 switch(artyp) { 781 case ISTAPE: 782 /* 783 * if the last i/o was a successful data transfer, we assume 784 * the fault is just a bad record on the tape that we are now 785 * past. If we did not get any data since the last resync try 786 * to move the tape forward one PHYSICAL record past any 787 * damaged tape section. Some tape drives are stubborn and need 788 * to be pushed. 789 */ 790 if (io_ok) { 791 io_ok = 0; 792 lstrval = 1; 793 break; 794 } 795 mb.mt_op = MTFSR; 796 mb.mt_count = 1; 797 if (ioctl(arfd, MTIOCTOP, &mb) < 0) 798 break; 799 lstrval = 1; 800 break; 801 case ISREG: 802 case ISCHR: 803 case ISBLK: 804 /* 805 * try to step over the bad part of the device. 806 */ 807 io_ok = 0; 808 if (((fsbz = arsb.st_blksize) <= 0) || (artyp != ISREG)) 809 fsbz = BLKMULT; 810 if ((cpos = lseek(arfd, (off_t)0L, SEEK_CUR)) < 0) 811 break; 812 mpos = fsbz - (cpos % (off_t)fsbz); 813 if (lseek(arfd, mpos, SEEK_CUR) < 0) 814 break; 815 lstrval = 1; 816 break; 817 case ISPIPE: 818 default: 819 /* 820 * cannot recover on these archive device types 821 */ 822 io_ok = 0; 823 break; 824 } 825 if (lstrval <= 0) { 826 paxwarn(1, "Unable to recover from an archive read failure."); 827 return(-1); 828 } 829 paxwarn(0, "Attempting to recover from an archive read failure."); 830 return(0); 831 } 832 833 /* 834 * ar_fow() 835 * Move the I/O position within the archive foward the specified number of 836 * bytes as supported by the device. If we cannot move the requested 837 * number of bytes, return the actual number of bytes moved in skipped. 838 * Return: 839 * 0 if moved the requested distance, -1 on complete failure, 1 on 840 * partial move (the amount moved is in skipped) 841 */ 842 843 #ifdef __STDC__ 844 int 845 ar_fow(off_t sksz, off_t *skipped) 846 #else 847 int 848 ar_fow(sksz, skipped) 849 off_t sksz; 850 off_t *skipped; 851 #endif 852 { 853 off_t cpos; 854 off_t mpos; 855 856 *skipped = 0; 857 if (sksz <= 0) 858 return(0); 859 860 /* 861 * we cannot move foward at EOF or error 862 */ 863 if (lstrval <= 0) 864 return(lstrval); 865 866 /* 867 * Safer to read forward on devices where it is hard to find the end of 868 * the media without reading to it. With tapes we cannot be sure of the 869 * number of physical blocks to skip (we do not know physical block 870 * size at this point), so we must only read foward on tapes! 871 */ 872 if (artyp != ISREG) 873 return(0); 874 875 /* 876 * figure out where we are in the archive 877 */ 878 if ((cpos = lseek(arfd, (off_t)0L, SEEK_CUR)) >= 0) { 879 /* 880 * we can be asked to move farther than there are bytes in this 881 * volume, if so, just go to file end and let normal buf_fill() 882 * deal with the end of file (it will go to next volume by 883 * itself) 884 */ 885 if ((mpos = cpos + sksz) > arsb.st_size) { 886 *skipped = arsb.st_size - cpos; 887 mpos = arsb.st_size; 888 } else 889 *skipped = sksz; 890 if (lseek(arfd, mpos, SEEK_SET) >= 0) 891 return(0); 892 } 893 syswarn(1, errno, "Forward positioning operation on archive failed"); 894 lstrval = -1; 895 return(-1); 896 } 897 898 /* 899 * ar_rev() 900 * move the i/o position within the archive backwards the specified byte 901 * count as supported by the device. With tapes drives we RESET rdblksz to 902 * the PHYSICAL blocksize. 903 * NOTE: We should only be called to move backwards so we can rewrite the 904 * last records (the trailer) of an archive (APPEND). 905 * Return: 906 * 0 if moved the requested distance, -1 on complete failure 907 */ 908 909 #ifdef __STDC__ 910 int 911 ar_rev(off_t sksz) 912 #else 913 int 914 ar_rev(sksz) 915 off_t sksz; 916 #endif 917 { 918 off_t cpos; 919 struct mtop mb; 920 register int phyblk; 921 922 /* 923 * make sure we do not have try to reverse on a flawed archive 924 */ 925 if (lstrval < 0) 926 return(lstrval); 927 928 switch(artyp) { 929 case ISPIPE: 930 if (sksz <= 0) 931 break; 932 /* 933 * cannot go backwards on these critters 934 */ 935 paxwarn(1, "Reverse positioning on pipes is not supported."); 936 lstrval = -1; 937 return(-1); 938 case ISREG: 939 case ISBLK: 940 case ISCHR: 941 default: 942 if (sksz <= 0) 943 break; 944 945 /* 946 * For things other than files, backwards movement has a very 947 * high probability of failure as we really do not know the 948 * true attributes of the device we are talking to (the device 949 * may not even have the ability to lseek() in any direction). 950 * First we figure out where we are in the archive. 951 */ 952 if ((cpos = lseek(arfd, (off_t)0L, SEEK_CUR)) < 0) { 953 syswarn(1, errno, 954 "Unable to obtain current archive byte offset"); 955 lstrval = -1; 956 return(-1); 957 } 958 959 /* 960 * we may try to go backwards past the start when the archive 961 * is only a single record. If this hapens and we are on a 962 * multi volume archive, we need to go to the end of the 963 * previous volume and continue our movement backwards from 964 * there. 965 */ 966 if ((cpos -= sksz) < (off_t)0L) { 967 if (arvol > 1) { 968 /* 969 * this should never happen 970 */ 971 paxwarn(1,"Reverse position on previous volume."); 972 lstrval = -1; 973 return(-1); 974 } 975 cpos = (off_t)0L; 976 } 977 if (lseek(arfd, cpos, SEEK_SET) < 0) { 978 syswarn(1, errno, "Unable to seek archive backwards"); 979 lstrval = -1; 980 return(-1); 981 } 982 break; 983 case ISTAPE: 984 /* 985 * Calculate and move the proper number of PHYSICAL tape 986 * blocks. If the sksz is not an even multiple of the physical 987 * tape size, we cannot do the move (this should never happen). 988 * (We also cannot handler trailers spread over two vols). 989 * get_phys() also makes sure we are in front of the filemark. 990 */ 991 if ((phyblk = get_phys()) <= 0) { 992 lstrval = -1; 993 return(-1); 994 } 995 996 /* 997 * make sure future tape reads only go by physical tape block 998 * size (set rdblksz to the real size). 999 */ 1000 rdblksz = phyblk; 1001 1002 /* 1003 * if no movement is required, just return (we must be after 1004 * get_phys() so the physical blocksize is properly set) 1005 */ 1006 if (sksz <= 0) 1007 break; 1008 1009 /* 1010 * ok we have to move. Make sure the tape drive can do it. 1011 */ 1012 if (sksz % phyblk) { 1013 paxwarn(1, 1014 "Tape drive unable to backspace requested amount"); 1015 lstrval = -1; 1016 return(-1); 1017 } 1018 1019 /* 1020 * move backwards the requested number of bytes 1021 */ 1022 mb.mt_op = MTBSR; 1023 mb.mt_count = sksz/phyblk; 1024 if (ioctl(arfd, MTIOCTOP, &mb) < 0) { 1025 syswarn(1,errno, "Unable to backspace tape %d blocks.", 1026 mb.mt_count); 1027 lstrval = -1; 1028 return(-1); 1029 } 1030 break; 1031 } 1032 lstrval = 1; 1033 return(0); 1034 } 1035 1036 /* 1037 * get_phys() 1038 * Determine the physical block size on a tape drive. We need the physical 1039 * block size so we know how many bytes we skip over when we move with 1040 * mtio commands. We also make sure we are BEFORE THE TAPE FILEMARK when 1041 * return. 1042 * This is one really SLOW routine... 1043 * Return: 1044 * physical block size if ok (ok > 0), -1 otherwise 1045 */ 1046 1047 #ifdef __STDC__ 1048 static int 1049 get_phys(void) 1050 #else 1051 static int 1052 get_phys() 1053 #endif 1054 { 1055 register int padsz = 0; 1056 register int res; 1057 register int phyblk; 1058 struct mtop mb; 1059 char scbuf[MAXBLK]; 1060 1061 /* 1062 * move to the file mark, and then back up one record and read it. 1063 * this should tell us the physical record size the tape is using. 1064 */ 1065 if (lstrval == 1) { 1066 /* 1067 * we know we are at file mark when we get back a 0 from 1068 * read() 1069 */ 1070 while ((res = read(arfd, scbuf, sizeof(scbuf))) > 0) 1071 padsz += res; 1072 if (res < 0) { 1073 syswarn(1, errno, "Unable to locate tape filemark."); 1074 return(-1); 1075 } 1076 } 1077 1078 /* 1079 * move backwards over the file mark so we are at the end of the 1080 * last record. 1081 */ 1082 mb.mt_op = MTBSF; 1083 mb.mt_count = 1; 1084 if (ioctl(arfd, MTIOCTOP, &mb) < 0) { 1085 syswarn(1, errno, "Unable to backspace over tape filemark."); 1086 return(-1); 1087 } 1088 1089 /* 1090 * move backwards so we are in front of the last record and read it to 1091 * get physical tape blocksize. 1092 */ 1093 mb.mt_op = MTBSR; 1094 mb.mt_count = 1; 1095 if (ioctl(arfd, MTIOCTOP, &mb) < 0) { 1096 syswarn(1, errno, "Unable to backspace over last tape block."); 1097 return(-1); 1098 } 1099 if ((phyblk = read(arfd, scbuf, sizeof(scbuf))) <= 0) { 1100 syswarn(1, errno, "Cannot determine archive tape blocksize."); 1101 return(-1); 1102 } 1103 1104 /* 1105 * read foward to the file mark, then back up in front of the filemark 1106 * (this is a bit paranoid, but should be safe to do). 1107 */ 1108 while ((res = read(arfd, scbuf, sizeof(scbuf))) > 0) 1109 ; 1110 if (res < 0) { 1111 syswarn(1, errno, "Unable to locate tape filemark."); 1112 return(-1); 1113 } 1114 mb.mt_op = MTBSF; 1115 mb.mt_count = 1; 1116 if (ioctl(arfd, MTIOCTOP, &mb) < 0) { 1117 syswarn(1, errno, "Unable to backspace over tape filemark."); 1118 return(-1); 1119 } 1120 1121 /* 1122 * set lstrval so we know that the filemark has not been seen 1123 */ 1124 lstrval = 1; 1125 1126 /* 1127 * return if there was no padding 1128 */ 1129 if (padsz == 0) 1130 return(phyblk); 1131 1132 /* 1133 * make sure we can move backwards over the padding. (this should 1134 * never fail). 1135 */ 1136 if (padsz % phyblk) { 1137 paxwarn(1, "Tape drive unable to backspace requested amount"); 1138 return(-1); 1139 } 1140 1141 /* 1142 * move backwards over the padding so the head is where it was when 1143 * we were first called (if required). 1144 */ 1145 mb.mt_op = MTBSR; 1146 mb.mt_count = padsz/phyblk; 1147 if (ioctl(arfd, MTIOCTOP, &mb) < 0) { 1148 syswarn(1,errno,"Unable to backspace tape over %d pad blocks", 1149 mb.mt_count); 1150 return(-1); 1151 } 1152 return(phyblk); 1153 } 1154 1155 /* 1156 * ar_next() 1157 * prompts the user for the next volume in this archive. For some devices 1158 * we may allow the media to be changed. Otherwise a new archive is 1159 * prompted for. By pax spec, if there is no controlling tty or an eof is 1160 * read on tty input, we must quit pax. 1161 * Return: 1162 * 0 when ready to continue, -1 when all done 1163 */ 1164 1165 #ifdef __STDC__ 1166 int 1167 ar_next(void) 1168 #else 1169 int 1170 ar_next() 1171 #endif 1172 { 1173 char buf[PAXPATHLEN+2]; 1174 static int freeit = 0; 1175 sigset_t o_mask; 1176 1177 /* 1178 * WE MUST CLOSE THE DEVICE. A lot of devices must see last close, (so 1179 * things like writing EOF etc will be done) (Watch out ar_close() can 1180 * also be called via a signal handler, so we must prevent a race. 1181 */ 1182 if (sigprocmask(SIG_BLOCK, &s_mask, &o_mask) < 0) 1183 syswarn(0, errno, "Unable to set signal mask"); 1184 ar_close(); 1185 if (sigprocmask(SIG_SETMASK, &o_mask, NULL) < 0) 1186 syswarn(0, errno, "Unable to restore signal mask"); 1187 1188 if (done || !wr_trail || strcmp(NM_TAR, argv0) == 0) 1189 return(-1); 1190 1191 tty_prnt("\nATTENTION! %s archive volume change required.\n", argv0); 1192 1193 /* 1194 * if i/o is on stdin or stdout, we cannot reopen it (we do not know 1195 * the name), the user will be forced to type it in. 1196 */ 1197 if (strcmp(arcname, STDO) && strcmp(arcname, STDN) && (artyp != ISREG) 1198 && (artyp != ISPIPE)) { 1199 if (artyp == ISTAPE) { 1200 tty_prnt("%s ready for archive tape volume: %d\n", 1201 arcname, arvol); 1202 tty_prnt("Load the NEXT TAPE on the tape drive"); 1203 } else { 1204 tty_prnt("%s ready for archive volume: %d\n", 1205 arcname, arvol); 1206 tty_prnt("Load the NEXT STORAGE MEDIA (if required)"); 1207 } 1208 1209 if ((act == ARCHIVE) || (act == APPND)) 1210 tty_prnt(" and make sure it is WRITE ENABLED.\n"); 1211 else 1212 tty_prnt("\n"); 1213 1214 for(;;) { 1215 tty_prnt("Type \"y\" to continue, \".\" to quit %s,", 1216 argv0); 1217 tty_prnt(" or \"s\" to switch to new device.\nIf you"); 1218 tty_prnt(" cannot change storage media, type \"s\"\n"); 1219 tty_prnt("Is the device ready and online? > "); 1220 1221 if ((tty_read(buf,sizeof(buf))<0) || !strcmp(buf,".")){ 1222 done = 1; 1223 lstrval = -1; 1224 tty_prnt("Quitting %s!\n", argv0); 1225 vfpart = 0; 1226 return(-1); 1227 } 1228 1229 if ((buf[0] == '\0') || (buf[1] != '\0')) { 1230 tty_prnt("%s unknown command, try again\n",buf); 1231 continue; 1232 } 1233 1234 switch (buf[0]) { 1235 case 'y': 1236 case 'Y': 1237 /* 1238 * we are to continue with the same device 1239 */ 1240 if (ar_open(arcname) >= 0) 1241 return(0); 1242 tty_prnt("Cannot re-open %s, try again\n", 1243 arcname); 1244 continue; 1245 case 's': 1246 case 'S': 1247 /* 1248 * user wants to open a different device 1249 */ 1250 tty_prnt("Switching to a different archive\n"); 1251 break; 1252 default: 1253 tty_prnt("%s unknown command, try again\n",buf); 1254 continue; 1255 } 1256 break; 1257 } 1258 } else 1259 tty_prnt("Ready for archive volume: %d\n", arvol); 1260 1261 /* 1262 * have to go to a different archive 1263 */ 1264 for (;;) { 1265 tty_prnt("Input archive name or \".\" to quit %s.\n", argv0); 1266 tty_prnt("Archive name > "); 1267 1268 if ((tty_read(buf, sizeof(buf)) < 0) || !strcmp(buf, ".")) { 1269 done = 1; 1270 lstrval = -1; 1271 tty_prnt("Quitting %s!\n", argv0); 1272 vfpart = 0; 1273 return(-1); 1274 } 1275 if (buf[0] == '\0') { 1276 tty_prnt("Empty file name, try again\n"); 1277 continue; 1278 } 1279 if (!strcmp(buf, "..")) { 1280 tty_prnt("Illegal file name: .. try again\n"); 1281 continue; 1282 } 1283 if (strlen(buf) > PAXPATHLEN) { 1284 tty_prnt("File name too long, try again\n"); 1285 continue; 1286 } 1287 1288 /* 1289 * try to open new archive 1290 */ 1291 if (ar_open(buf) >= 0) { 1292 if (freeit) { 1293 (void)free(arcname); 1294 freeit = 0; 1295 } 1296 if ((arcname = strdup(buf)) == NULL) { 1297 done = 1; 1298 lstrval = -1; 1299 paxwarn(0, "Cannot save archive name."); 1300 return(-1); 1301 } 1302 freeit = 1; 1303 break; 1304 } 1305 tty_prnt("Cannot open %s, try again\n", buf); 1306 continue; 1307 } 1308 return(0); 1309 } 1310 1311 /* 1312 * ar_start_gzip() 1313 * starts the gzip compression/decompression process as a child, using magic 1314 * to keep the fd the same in the calling function (parent). 1315 */ 1316 void 1317 ar_start_gzip(int fd, const char *gzip_program, int wr) 1318 { 1319 int fds[2]; 1320 char *gzip_flags; 1321 1322 if (pipe(fds) < 0) 1323 err(1, "could not pipe"); 1324 zpid = fork(); 1325 if (zpid < 0) 1326 err(1, "could not fork"); 1327 1328 /* parent */ 1329 if (zpid) { 1330 if (wr) 1331 dup2(fds[1], fd); 1332 else 1333 dup2(fds[0], fd); 1334 close(fds[0]); 1335 close(fds[1]); 1336 } else { 1337 if (wr) { 1338 dup2(fds[0], STDIN_FILENO); 1339 dup2(fd, STDOUT_FILENO); 1340 gzip_flags = "-c"; 1341 } else { 1342 dup2(fds[1], STDOUT_FILENO); 1343 dup2(fd, STDIN_FILENO); 1344 gzip_flags = "-dc"; 1345 } 1346 close(fds[0]); 1347 close(fds[1]); 1348 if (execlp(gzip_program, gzip_program, gzip_flags, 1349 (char *)NULL) < 0) 1350 err(1, "could not exec"); 1351 /* NOTREACHED */ 1352 } 1353 } 1354