3 * block.c -- tape block handling functions
5 * Kern Sibbald, March MMI
6 * added BB02 format October MMII
12 Copyright (C) 2000-2003 Kern Sibbald and John Walker
14 This program is free software; you can redistribute it and/or
15 modify it under the terms of the GNU General Public License as
16 published by the Free Software Foundation; either version 2 of
17 the License, or (at your option) any later version.
19 This program is distributed in the hope that it will be useful,
20 but WITHOUT ANY WARRANTY; without even the implied warranty of
21 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
22 General Public License for more details.
24 You should have received a copy of the GNU General Public
25 License along with this program; if not, write to the Free
26 Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
35 extern int debug_level;
38 * Dump the block header, then walk through
39 * the block printing out the record headers.
41 void dump_block(DEV_BLOCK *b, char *msg)
45 char Id[BLKHDR_ID_LENGTH+1];
46 uint32_t CheckSum, BlockCheckSum;
49 uint32_t VolSessionId, VolSessionTime, data_len;
54 unser_begin(b->buf, BLKHDR1_LENGTH);
55 unser_uint32(CheckSum);
56 unser_uint32(block_len);
57 unser_uint32(BlockNumber);
58 unser_bytes(Id, BLKHDR_ID_LENGTH);
59 ASSERT(unser_length(b->buf) == BLKHDR1_LENGTH);
60 Id[BLKHDR_ID_LENGTH] = 0;
62 unser_uint32(VolSessionId);
63 unser_uint32(VolSessionTime);
67 VolSessionId = VolSessionTime = 0;
72 if (block_len > 100000) {
73 Dmsg3(20, "Dump block %s 0x%x blocksize too big %u\n", msg, b, block_len);
77 BlockCheckSum = bcrc32((uint8_t *)b->buf+BLKHDR_CS_LENGTH,
78 block_len-BLKHDR_CS_LENGTH);
79 Pmsg6(000, "Dump block %s %x: size=%d BlkNum=%d\n\
80 Hdrcksum=%x cksum=%x\n",
81 msg, b, block_len, BlockNumber, CheckSum, BlockCheckSum);
83 while (p < (b->buf + block_len+WRITE_RECHDR_LENGTH)) {
84 unser_begin(p, WRITE_RECHDR_LENGTH);
85 if (rhl == RECHDR1_LENGTH) {
86 unser_uint32(VolSessionId);
87 unser_uint32(VolSessionTime);
89 unser_int32(FileIndex);
91 unser_uint32(data_len);
92 Pmsg6(000, " Rec: VId=%u VT=%u FI=%s Strm=%s len=%d p=%x\n",
93 VolSessionId, VolSessionTime, FI_to_ascii(FileIndex),
94 stream_to_ascii(Stream, FileIndex), data_len, p);
100 * Create a new block structure.
101 * We pass device so that the block can inherit the
102 * min and max block sizes.
104 DEV_BLOCK *new_block(DEVICE *dev)
106 DEV_BLOCK *block = (DEV_BLOCK *)get_memory(sizeof(DEV_BLOCK));
108 memset(block, 0, sizeof(DEV_BLOCK));
110 /* If the user has specified a max_block_size, use it as the default */
111 if (dev->max_block_size == 0) {
112 block->buf_len = DEFAULT_BLOCK_SIZE;
114 block->buf_len = dev->max_block_size;
117 block->block_len = block->buf_len; /* default block size */
118 block->buf = get_memory(block->buf_len);
119 if (block->buf == NULL) {
120 Mmsg0(&dev->errmsg, _("Unable to malloc block buffer.\n"));
121 Emsg0(M_FATAL, 0, dev->errmsg);
125 block->BlockVer = BLOCK_VER; /* default write version */
126 Dmsg1(90, "Returning new block=%x\n", block);
131 * Only the first block checksum error was reported.
132 * If there are more, report it now.
134 void print_block_errors(JCR *jcr, DEV_BLOCK *block)
136 if (block->checksum_errors > 1) {
137 Jmsg(jcr, M_ERROR, 0, _("%d block checksum errors ignored.\n"),
138 block->checksum_errors);
145 void free_block(DEV_BLOCK *block)
147 Dmsg1(199, "free_block buffer %x\n", block->buf);
148 free_memory(block->buf);
149 Dmsg1(199, "free_block block %x\n", block);
150 free_memory((POOLMEM *)block);
153 /* Empty the block -- for writing */
154 void empty_block(DEV_BLOCK *block)
156 block->binbuf = WRITE_BLKHDR_LENGTH;
157 block->bufp = block->buf + block->binbuf;
159 block->write_failed = false;
160 block->block_read = false;
161 block->FirstIndex = block->LastIndex = 0;
165 * Create block header just before write. The space
166 * in the buffer should have already been reserved by
169 static void ser_block_header(DEV_BLOCK *block)
172 uint32_t CheckSum = 0;
173 uint32_t block_len = block->binbuf;
175 Dmsg1(190, "ser_block_header: block_len=%d\n", block_len);
176 ser_begin(block->buf, BLKHDR2_LENGTH);
177 ser_uint32(CheckSum);
178 ser_uint32(block_len);
179 ser_uint32(block->BlockNumber);
180 ser_bytes(WRITE_BLKHDR_ID, BLKHDR_ID_LENGTH);
181 if (BLOCK_VER >= 2) {
182 ser_uint32(block->VolSessionId);
183 ser_uint32(block->VolSessionTime);
186 /* Checksum whole block except for the checksum */
187 CheckSum = bcrc32((uint8_t *)block->buf+BLKHDR_CS_LENGTH,
188 block_len-BLKHDR_CS_LENGTH);
189 Dmsg1(190, "ser_bloc_header: checksum=%x\n", CheckSum);
190 ser_begin(block->buf, BLKHDR2_LENGTH);
191 ser_uint32(CheckSum); /* now add checksum to block header */
195 * Unserialize the block header for reading block.
196 * This includes setting all the buffer pointers correctly.
198 * Returns: 0 on failure (not a block)
201 static int unser_block_header(JCR *jcr, DEVICE *dev, DEV_BLOCK *block)
204 char Id[BLKHDR_ID_LENGTH+1];
205 uint32_t CheckSum, BlockCheckSum;
208 uint32_t BlockNumber;
211 unser_begin(block->buf, BLKHDR_LENGTH);
212 unser_uint32(CheckSum);
213 unser_uint32(block_len);
214 unser_uint32(BlockNumber);
215 unser_bytes(Id, BLKHDR_ID_LENGTH);
216 ASSERT(unser_length(block->buf) == BLKHDR1_LENGTH);
218 Id[BLKHDR_ID_LENGTH] = 0;
220 bhl = BLKHDR1_LENGTH;
222 block->bufp = block->buf + bhl;
223 if (strncmp(Id, BLKHDR1_ID, BLKHDR_ID_LENGTH) != 0) {
224 Mmsg2(&dev->errmsg, _("Buffer ID error. Wanted: %s, got %s. Buffer discarded.\n"),
226 Emsg0(M_ERROR, 0, dev->errmsg);
229 } else if (Id[3] == '2') {
230 unser_uint32(block->VolSessionId);
231 unser_uint32(block->VolSessionTime);
232 bhl = BLKHDR2_LENGTH;
234 block->bufp = block->buf + bhl;
235 if (strncmp(Id, BLKHDR2_ID, BLKHDR_ID_LENGTH) != 0) {
236 Mmsg2(&dev->errmsg, _("Buffer ID error. Wanted: %s, got %s. Buffer discarded.\n"),
238 Emsg0(M_ERROR, 0, dev->errmsg);
242 Mmsg1(&dev->errmsg, _("Expected block-id BB01 or BB02, got %s. Buffer discarded.\n"), Id);
243 Emsg0(M_ERROR, 0, dev->errmsg);
248 if (block_len > MAX_BLOCK_LENGTH) {
249 Mmsg1(&dev->errmsg, _("Block length %u is insane (too large), probably due to a bad archive.\n"),
251 Emsg0(M_ERROR, 0, dev->errmsg);
255 Dmsg1(190, "unser_block_header block_len=%d\n", block_len);
256 /* Find end of block or end of buffer whichever is smaller */
257 if (block_len > block->read_len) {
258 block_end = block->read_len;
260 block_end = block_len;
262 block->binbuf = block_end - bhl;
263 block->block_len = block_len;
264 block->BlockNumber = BlockNumber;
265 Dmsg3(190, "Read binbuf = %d %d block_len=%d\n", block->binbuf,
267 if (block_len <= block->read_len) {
268 BlockCheckSum = bcrc32((uint8_t *)block->buf+BLKHDR_CS_LENGTH,
269 block_len-BLKHDR_CS_LENGTH);
270 if (BlockCheckSum != CheckSum) {
271 Dmsg2(00, "Block checksum mismatch: calc=%x blk=%x\n", BlockCheckSum,
273 Mmsg3(&dev->errmsg, _("Block checksum mismatch in block %u: calc=%x blk=%x\n"),
274 (unsigned)BlockNumber, BlockCheckSum, CheckSum);
275 if (block->checksum_errors == 0) {
276 Jmsg(jcr, M_ERROR, 0, "%s", dev->errmsg);
278 block->checksum_errors++;
285 * Write a block to the device, with locking and unlocking
287 * Returns: 1 on success
291 int write_block_to_device(JCR *jcr, DEVICE *dev, DEV_BLOCK *block)
297 * If a new volume has been mounted since our last write
298 * Create a JobMedia record for the previous volume written,
299 * and set new parameters to write this volume
300 * The saem applies for if we are in a new file.
302 if (jcr->NewVol || jcr->NewFile) {
303 /* Create a jobmedia record for this job */
304 if (!dir_create_jobmedia_record(jcr)) {
305 Jmsg(jcr, M_ERROR, 0, _("Could not create JobMedia record for Volume=\"%s\" Job=%s\n"),
306 jcr->VolCatInfo.VolCatName, jcr->Job);
307 set_new_volume_parameters(jcr, dev);
312 /* Note, setting a new volume also handles any pending new file */
313 set_new_volume_parameters(jcr, dev);
314 jcr->NewFile = false; /* this handled for new file too */
316 set_new_file_parameters(jcr, dev);
320 if (!write_block_to_dev(jcr, dev, block)) {
321 stat = fixup_device_block_write_error(jcr, dev, block);
329 * Write a block to the device
331 * Returns: 1 on success or EOT
334 int write_block_to_dev(JCR *jcr, DEVICE *dev, DEV_BLOCK *block)
337 uint32_t wlen; /* length to write */
338 int hit_max1, hit_max2;
341 #ifdef NO_TAPE_WRITE_TEST
345 ASSERT(block->binbuf == ((uint32_t) (block->bufp - block->buf)));
347 /* dump_block(block, "before write"); */
348 if (dev->state & ST_WEOT) {
349 Dmsg0(100, "return write_block_to_dev with ST_WEOT\n");
350 Jmsg(jcr, M_FATAL, 0, _("Cannot write block. Device at EOM.\n"));
353 wlen = block->binbuf;
354 if (wlen <= WRITE_BLKHDR_LENGTH) { /* Does block have data in it? */
355 Dmsg0(100, "return write_block_to_dev no data to write\n");
359 * Clear to the end of the buffer if it is not full,
360 * and on tape devices, apply min and fixed blocking.
362 if (wlen != block->buf_len) {
363 uint32_t blen; /* current buffer length */
365 Dmsg2(200, "binbuf=%d buf_len=%d\n", block->binbuf, block->buf_len);
368 /* Adjust write size to min/max for tapes only */
369 if (dev->state & ST_TAPE) {
370 if (wlen < dev->min_block_size) {
371 wlen = ((dev->min_block_size + TAPE_BSIZE - 1) / TAPE_BSIZE) * TAPE_BSIZE;
373 /* check for fixed block size */
374 if (dev->min_block_size == dev->max_block_size) {
375 wlen = block->buf_len; /* fixed block size already rounded */
379 memset(block->bufp, 0, wlen-blen); /* clear garbage */
383 ser_block_header(block);
385 /* Limit maximum Volume size to value specified by user */
386 hit_max1 = (dev->max_volume_size > 0) &&
387 ((dev->VolCatInfo.VolCatBytes + block->binbuf)) >= dev->max_volume_size;
388 hit_max2 = (dev->VolCatInfo.VolCatMaxBytes > 0) &&
389 ((dev->VolCatInfo.VolCatBytes + block->binbuf)) >= dev->VolCatInfo.VolCatMaxBytes;
390 if (hit_max1 || hit_max2) {
393 Dmsg0(10, "==== Output bytes Triggered medium max capacity.\n");
395 max_cap = dev->max_volume_size;
397 max_cap = dev->VolCatInfo.VolCatMaxBytes;
399 Jmsg(jcr, M_INFO, 0, _("User defined maximum volume capacity %s exceeded on device %s.\n"),
400 edit_uint64(max_cap, ed1), dev->dev_name);
401 block->write_failed = true;
402 weof_dev(dev, 1); /* end the tape */
404 dev->state |= (ST_EOF | ST_EOT | ST_WEOT);
408 /* Limit maximum File size on volume to user specified value */
409 if (dev->state & ST_TAPE) {
410 if ((dev->max_file_size > 0) &&
411 (dev->file_addr+block->binbuf) >= dev->max_file_size) {
414 if (weof_dev(dev, 1) != 0) { /* write eof */
415 Jmsg(jcr, M_ERROR, 0, "%s", dev->errmsg);
416 block->write_failed = true;
417 dev->state |= (ST_EOF | ST_EOT | ST_WEOT);
421 /* Do bookkeeping to handle EOF just written */
422 if (!dir_create_jobmedia_record(jcr)) {
423 Jmsg(jcr, M_ERROR, 0, _("Could not create JobMedia record for Volume=\"%s\" Job=%s\n"),
424 jcr->VolCatInfo.VolCatName, jcr->Job);
428 * Walk through all attached jcrs indicating the file has changed
430 Dmsg1(100, "Walk attached jcrs. Volume=%s\n", dev->VolCatInfo.VolCatName);
431 for (JCR *mjcr=NULL; (mjcr=next_attached_jcr(dev, mjcr)); ) {
432 if (mjcr->JobId == 0) {
433 continue; /* ignore console */
435 mjcr->NewFile = true;
437 set_new_file_parameters(jcr, dev);
441 dev->VolCatInfo.VolCatWrites++;
442 Dmsg1(300, "Write block of %u bytes\n", wlen);
443 stat = write(dev->fd, block->buf, (size_t)wlen);
444 if (stat != (ssize_t)wlen) {
445 /* We should check for errno == ENOSPC, BUT many
446 * devices simply report EIO when the volume is full.
447 * With a little more thought we may be able to check
448 * capacity and distinguish real errors and EOT
449 * conditions. In any case, we probably want to
450 * simulate an End of Medium.
453 /* I have added the ifdefing here because it appears on
454 * FreeBSD where MTIOCERRSTAT is defined, this not only
455 * clears the error but clears the residual unwritten
456 * buffers -> data loss. As a consequence, on those
457 * systems (FreeBSD like), do the clrerror() only after
458 * the weof_dev() call.
460 clrerror_dev(dev, -1);
461 if (dev->dev_errno == 0) {
462 dev->dev_errno = ENOSPC; /* out of space */
464 Jmsg(jcr, M_ERROR, 0, _("Write error on device %s. ERR=%s.\n"),
465 dev->dev_name, strerror(dev->dev_errno));
467 dev->dev_errno = ENOSPC; /* out of space */
468 Jmsg3(jcr, M_INFO, 0, _("End of medium on device %s. Write of %u bytes got %d.\n"),
469 dev->dev_name, wlen, stat);
472 Dmsg6(100, "=== Write error. size=%u rtn=%d dev_blk=%d blk_blk=%d errno=%d: ERR=%s\n",
473 wlen, stat, dev->block_num, block->BlockNumber, dev->dev_errno, strerror(dev->dev_errno));
475 block->write_failed = true;
477 if (weof_dev(dev, 1) != 0) { /* end the tape */
478 Jmsg(jcr, M_ERROR, 0, "%s", dev->errmsg);
480 dev->state |= (ST_EOF | ST_EOT | ST_WEOT);
483 #define CHECK_LAST_BLOCK
484 #ifdef CHECK_LAST_BLOCK
486 * If the device is a tape and it supports backspace record,
487 * we backspace over two eof marks and over the last record,
488 * then re-read it and verify that the block number is
491 if (dev->state & ST_TAPE && dev_cap(dev, CAP_BSR)) {
493 /* Now back up over what we wrote and read the last block */
494 if (bsf_dev(dev, 1) != 0 || bsf_dev(dev, 1) != 0) {
496 Jmsg(jcr, M_ERROR, 0, _("Backspace file at EOT failed. ERR=%s\n"), strerror(dev->dev_errno));
498 /* Backspace over record */
499 if (ok && bsr_dev(dev, 1) != 0) {
501 Jmsg(jcr, M_ERROR, 0, _("Backspace record at EOT failed. ERR=%s\n"), strerror(dev->dev_errno));
503 * On FreeBSD systems, if the user got here, it is likely that his/her
504 * tape drive is "frozen". The correct thing to do is a
505 * rewind(), but if we do that, higher levels in cleaning up, will
506 * most likely write the EOS record over the beginning of the
507 * tape. The rewind *is* done later in mount.c when another
508 * tape is requested. Note, the clrerror_dev() call in bsr_dev()
509 * calls ioctl(MTCERRSTAT), which *should* fix the problem.
513 DEV_BLOCK *lblock = new_block(dev);
514 /* Note, this can destroy dev->errmsg */
515 if (!read_block_from_dev(jcr, dev, lblock, NO_BLOCK_NUMBER_CHECK)) {
516 Jmsg(jcr, M_ERROR, 0, _("Re-read last block at EOT failed. ERR=%s"), dev->errmsg);
518 if (lblock->BlockNumber+1 == block->BlockNumber) {
519 Jmsg(jcr, M_INFO, 0, _("Re-read of last block succeeded.\n"));
521 Jmsg(jcr, M_ERROR, 0, _(
522 "Re-read of last block failed. Last block=%u Current block=%u.\n"),
523 lblock->BlockNumber, block->BlockNumber);
533 /* We successfully wrote the block, now do housekeeping */
535 dev->VolCatInfo.VolCatBytes += block->binbuf;
536 dev->VolCatInfo.VolCatBlocks++;
537 dev->file_addr += wlen;
538 dev->EndBlock = dev->block_num;
539 dev->EndFile = dev->file;
541 block->BlockNumber++;
543 /* Update jcr values */
544 if (dev->state & ST_TAPE) {
545 jcr->EndBlock = dev->EndBlock;
546 jcr->EndFile = dev->EndFile;
548 jcr->EndBlock = (uint32_t)dev->file_addr;
549 jcr->EndFile = (uint32_t)(dev->file_addr >> 32);
551 if (jcr->VolFirstIndex == 0 && block->FirstIndex > 0) {
552 jcr->VolFirstIndex = block->FirstIndex;
554 if (block->LastIndex > 0) {
555 jcr->VolLastIndex = block->LastIndex;
557 jcr->WroteVol = true;
559 Dmsg2(190, "write_block: wrote block %d bytes=%d\n", dev->block_num,
566 * Read block with locking
569 int read_block_from_device(JCR *jcr, DEVICE *dev, DEV_BLOCK *block, bool check_block_numbers)
572 Dmsg0(90, "Enter read_block_from_device\n");
574 stat = read_block_from_dev(jcr, dev, block, check_block_numbers);
576 Dmsg0(90, "Leave read_block_from_device\n");
581 * Read the next block into the block structure and unserialize
582 * the block header. For a file, the block may be partially
583 * or completely in the current buffer.
585 int read_block_from_dev(JCR *jcr, DEVICE *dev, DEV_BLOCK *block, bool check_block_numbers)
589 uint32_t BlockNumber;
592 if (dev_state(dev, ST_EOT)) {
596 Dmsg1(100, "Full read() in read_block_from_device() len=%d\n",
600 Mmsg1(&dev->errmsg, _("Block buffer size looping problem on device %s\n"),
602 Jmsg(jcr, M_ERROR, 0, "%s", dev->errmsg);
608 stat = read(dev->fd, block->buf, (size_t)block->buf_len);
610 dev->VolCatInfo.VolCatErrors++;
612 } while (stat == -1 && (errno == EINTR || errno == EIO) && retry++ < 11);
613 // Dmsg1(000, "read stat = %d\n", stat);
615 Dmsg1(90, "Read device got: ERR=%s\n", strerror(errno));
616 clrerror_dev(dev, -1);
618 Mmsg2(&dev->errmsg, _("Read error on device %s. ERR=%s.\n"),
619 dev->dev_name, strerror(dev->dev_errno));
620 Jmsg(jcr, M_ERROR, 0, "%s", dev->errmsg);
621 if (dev->state & ST_EOF) { /* EOF just seen? */
622 dev->state |= ST_EOT; /* yes, error => EOT */
626 Dmsg1(90, "Read device got %d bytes\n", stat);
627 if (stat == 0) { /* Got EOF ! */
628 dev->block_num = block->read_len = 0;
629 Mmsg1(&dev->errmsg, _("Read zero bytes on device %s.\n"), dev->dev_name);
630 if (dev->state & ST_EOF) { /* EOF already read? */
631 dev->state |= ST_EOT; /* yes, 2 EOFs => EOT */
635 dev->file++; /* increment file */
636 dev->state |= ST_EOF; /* set EOF read */
638 return 0; /* return eof */
640 /* Continue here for successful read */
641 block->read_len = stat; /* save length read */
642 if (block->read_len < BLKHDR2_LENGTH) {
643 Mmsg2(&dev->errmsg, _("Very short block of %d bytes on device %s discarded.\n"),
644 block->read_len, dev->dev_name);
645 Jmsg(jcr, M_ERROR, 0, "%s", dev->errmsg);
646 dev->state |= ST_SHORT; /* set short block */
647 block->read_len = block->binbuf = 0;
648 return 0; /* return error */
651 BlockNumber = block->BlockNumber + 1;
652 if (!unser_block_header(jcr, dev, block)) {
653 Jmsg(jcr, M_ERROR, 0, "%s", dev->errmsg);
659 * If the block is bigger than the buffer, we reposition for
660 * re-reading the block, allocate a buffer of the correct size,
663 if (block->block_len > block->buf_len) {
664 Mmsg2(&dev->errmsg, _("Block length %u is greater than buffer %u. Attempting recovery.\n"),
665 block->block_len, block->buf_len);
666 Jmsg(jcr, M_ERROR, 0, "%s", dev->errmsg);
667 Pmsg1(000, "%s", dev->errmsg);
668 /* Attempt to reposition to re-read the block */
669 if (dev->state & ST_TAPE) {
670 Dmsg0(100, "Backspace record for reread.\n");
671 if (bsr_dev(dev, 1) != 0) {
672 Jmsg(jcr, M_ERROR, 0, "%s", dev->errmsg);
677 Dmsg0(100, "Seek to beginning of block for reread.\n");
678 off_t pos = lseek(dev->fd, (off_t)0, SEEK_CUR); /* get curr pos */
679 pos -= block->read_len;
680 lseek(dev->fd, pos, SEEK_SET);
682 Mmsg1(&dev->errmsg, _("Setting block buffer size to %u bytes.\n"), block->block_len);
683 Jmsg(jcr, M_INFO, 0, "%s", dev->errmsg);
684 Pmsg1(000, "%s", dev->errmsg);
685 /* Set new block length */
686 dev->max_block_size = block->block_len;
687 block->buf_len = block->block_len;
688 free_memory(block->buf);
689 block->buf = get_memory(block->buf_len);
692 goto reread; /* re-read block with correct block size */
695 if (block->block_len > block->read_len) {
696 Mmsg3(&dev->errmsg, _("Short block at %u of %d bytes on device %s discarded.\n"),
697 dev->block_num, block->read_len, dev->dev_name);
698 Jmsg(jcr, M_ERROR, 0, "%s", dev->errmsg);
699 dev->state |= ST_SHORT; /* set short block */
700 block->read_len = block->binbuf = 0;
701 return 0; /* return error */
704 dev->state &= ~(ST_EOF|ST_SHORT); /* clear EOF and short block */
705 dev->VolCatInfo.VolCatReads++;
706 dev->VolCatInfo.VolCatRBytes += block->read_len;
708 dev->VolCatInfo.VolCatBytes += block->block_len;
709 dev->VolCatInfo.VolCatBlocks++;
710 dev->file_addr += block->block_len;
711 dev->EndBlock = dev->block_num;
712 dev->EndFile = dev->file;
715 /* Update jcr values */
716 if (dev->state & ST_TAPE) {
717 jcr->EndBlock = dev->EndBlock;
718 jcr->EndFile = dev->EndFile;
720 jcr->EndBlock = (uint32_t)dev->file_addr;
721 jcr->EndFile = (uint32_t)(dev->file_addr >> 32);
725 * If we read a short block on disk,
726 * seek to beginning of next block. This saves us
727 * from shuffling blocks around in the buffer. Take a
728 * look at this from an efficiency stand point later, but
729 * it should only happen once at the end of each job.
731 * I've been lseek()ing negative relative to SEEK_CUR for 30
732 * years now. However, it seems that with the new off_t definition,
733 * it is not possible to seek negative amounts, so we use two
734 * lseek(). One to get the position, then the second to do an
735 * absolute positioning -- so much for efficiency. KES Sep 02.
737 Dmsg0(200, "At end of read block\n");
738 if (block->read_len > block->block_len && !(dev->state & ST_TAPE)) {
739 off_t pos = lseek(dev->fd, (off_t)0, SEEK_CUR); /* get curr pos */
740 pos -= (block->read_len - block->block_len);
741 lseek(dev->fd, pos, SEEK_SET);
742 Dmsg2(100, "Did lseek blk_size=%d rdlen=%d\n", block->block_len,
745 Dmsg2(200, "Exit read_block read_len=%d block_len=%d\n",
746 block->read_len, block->block_len);
747 block->block_read = true;