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ar_io.c
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/* $NetBSD: ar_io.c,v 1.12 2010/03/21 16:35:01 joerg Exp $ */
/*-
* Copyright (c) 1992 Keith Muller.
* Copyright (c) 1992, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Keith Muller of the University of California, San Diego.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#if HAVE_CONFIG_H
#include "config.h"
#endif
#if HAVE_NBTOOL_CONFIG_H
#include "nbtool_config.h"
#endif
#include <nbcompat.h>
#if HAVE_SYS_CDEFS_H
#include <sys/cdefs.h>
#endif
#if !defined(lint)
#if 0
static char sccsid[] = "@(#)ar_io.c 8.2 (Berkeley) 4/18/94";
#else
__RCSID("$NetBSD: ar_io.c,v 1.12 2010/03/21 16:35:01 joerg Exp $");
#endif
#endif /* not lint */
#if HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#if HAVE_SYS_PARAM_H
#include <sys/param.h>
#endif
#if HAVE_SYS_TIME_H
#include <sys/time.h>
#endif
#if HAVE_SYS_STAT_H
#include <sys/stat.h>
#endif
#if HAVE_SYS_IOCTL_H
#include <sys/ioctl.h>
#endif
#if HAVE_SYS_MTIO_H
#include <sys/mtio.h>
#elif HAVE_SYS_TAPE_H
#include <sys/tape.h>
#include "tape_h_fixup.h"
#endif
#if HAVE_SYS_WAIT_H
#include <sys/wait.h>
#endif
#if HAVE_SIGNAL_H
#include <signal.h>
#endif
#if HAVE_STRING_H
#include <string.h>
#endif
#if HAVE_FCNTL_H
#include <fcntl.h>
#endif
#if HAVE_UNISTD_H
#include <unistd.h>
#endif
#if HAVE_STDIO_H
#include <stdio.h>
#endif
#if HAVE_CTYPE_H
#include <ctype.h>
#endif
#if HAVE_ERRNO_H
#include <errno.h>
#endif
#if HAVE_STDLIB_H
#include <stdlib.h>
#endif
#ifdef SUPPORT_RMT
#define __RMTLIB_PRIVATE
#if HAVE_RMT_H
#include <rmt.h>
#endif
#endif /* SUPPORT_RMT */
#include "pax.h"
#include "options.h"
#include "extern.h"
/*
* Routines which deal directly with the archive I/O device/file.
*/
#define DMOD 0666 /* default mode of created archives */
#define EXT_MODE O_RDONLY /* open mode for list/extract */
#define AR_MODE (O_WRONLY | O_CREAT | O_TRUNC) /* mode for archive */
#define APP_MODE O_RDWR /* mode for append */
static char STDO[] = "<STDOUT>"; /* pseudo name for stdout */
static char STDN[] = "<STDIN>"; /* pseudo name for stdin */
static char NONE[] = "<NONE>"; /* pseudo name for none */
static int arfd = -1; /* archive file descriptor */
static int artyp = ISREG; /* archive type: file/FIFO/tape */
static int arvol = 1; /* archive volume number */
static int lstrval = -1; /* return value from last i/o */
static int io_ok; /* i/o worked on volume after resync */
static int did_io; /* did i/o ever occur on volume? */
static int done; /* set via tty termination */
static struct stat arsb; /* stat of archive device at open */
static int invld_rec; /* tape has out of spec record size */
static int wr_trail = 1; /* trailer was rewritten in append */
static int can_unlnk = 0; /* do we unlink null archives? */
const char *arcname; /* printable name of archive */
const char *gzip_program; /* name of gzip program */
static pid_t zpid = -1; /* pid of child process */
time_t starttime; /* time the run started */
int force_one_volume; /* 1 if we ignore volume changes */
#ifdef SUPPORT_TAPE
static int get_phys(void);
#endif /* SUPPORT_TAPE */
extern sigset_t s_mask;
static void ar_start_gzip(int, const char *, int);
static const char *timefmt(char *, size_t, off_t, time_t, const char *);
static const char *sizefmt(char *, size_t, off_t);
#ifdef SUPPORT_RMT
#ifdef SYS_NO_RESTART
static int rmtread_with_restart(int, void *, int);
static int rmtwrite_with_restart(int, void *, int);
#else
#define rmtread_with_restart(a, b, c) rmtread((a), (b), (c))
#define rmtwrite_with_restart(a, b, c) rmtwrite((a), (b), (c))
#endif
#endif /* SUPPORT_RMT */
/*
* ar_open()
* Opens the next archive volume. Determines the type of the device and
* sets up block sizes as required by the archive device and the format.
* Note: we may be called with name == NULL on the first open only.
* Return:
* -1 on failure, 0 otherwise
*/
int
ar_open(const char *name)
{
#ifdef SUPPORT_TAPE
struct mtget mb;
#endif /* SUPPORT_TAPE */
if (arfd != -1)
(void)close(arfd);
arfd = -1;
can_unlnk = did_io = io_ok = invld_rec = 0;
artyp = ISREG;
flcnt = 0;
#ifdef SUPPORT_RMT
if (name && strchr(name, ':') != NULL && !forcelocal) {
artyp = ISRMT;
if ((arfd = rmtopen(name, O_RDWR, DMOD)) == -1) {
syswarn(0, errno, "Failed open on %s", name);
return -1;
}
blksz = rdblksz = 8192;
lstrval = 1;
return 0;
}
#endif /* SUPPORT_RMT */
/*
* open based on overall operation mode
*/
switch (act) {
case LIST:
case EXTRACT:
if (name == NULL) {
arfd = STDIN_FILENO;
arcname = STDN;
} else if ((arfd = open(name, EXT_MODE, DMOD)) < 0)
syswarn(0, errno, "Failed open to read on %s", name);
if (arfd != -1 && gzip_program != NULL)
ar_start_gzip(arfd, gzip_program, 0);
break;
case ARCHIVE:
if (name == NULL) {
arfd = STDOUT_FILENO;
arcname = STDO;
} else if ((arfd = open(name, AR_MODE, DMOD)) < 0)
syswarn(0, errno, "Failed open to write on %s", name);
else
can_unlnk = 1;
if (arfd != -1 && gzip_program != NULL)
ar_start_gzip(arfd, gzip_program, 1);
break;
case APPND:
if (name == NULL) {
arfd = STDOUT_FILENO;
arcname = STDO;
} else if ((arfd = open(name, APP_MODE, DMOD)) < 0)
syswarn(0, errno, "Failed open to read/write on %s",
name);
break;
case COPY:
/*
* arfd not used in COPY mode
*/
arcname = NONE;
lstrval = 1;
return 0;
}
if (arfd < 0)
return -1;
if (chdname != NULL)
if (dochdir(chdname) == -1)
return -1;
/*
* set up is based on device type
*/
if (fstat(arfd, &arsb) < 0) {
syswarn(0, errno, "Failed stat on %s", arcname);
(void)close(arfd);
arfd = -1;
can_unlnk = 0;
return -1;
}
if (S_ISDIR(arsb.st_mode)) {
tty_warn(0, "Cannot write an archive on top of a directory %s",
arcname);
(void)close(arfd);
arfd = -1;
can_unlnk = 0;
return -1;
}
if (S_ISCHR(arsb.st_mode)) {
#ifdef SUPPORT_TAPE
artyp = ioctl(arfd, MTIOCGET, &mb) ? ISCHR : ISTAPE;
#else
tty_warn(1, "System does not have tape support");
artyp = ISREG;
#endif /* SUPPORT_TAPE */
} else if (S_ISBLK(arsb.st_mode))
artyp = ISBLK;
else if ((lseek(arfd, (off_t)0L, SEEK_CUR) == -1) && (errno == ESPIPE))
artyp = ISPIPE;
else
artyp = ISREG;
/*
* Special handling for empty files.
*/
if (artyp == ISREG && arsb.st_size == 0) {
switch (act) {
case LIST:
case EXTRACT:
return -1;
case APPND:
act = -ARCHIVE;
return -1;
case ARCHIVE:
break;
}
}
/*
* make sure we beyond any doubt that we only can unlink regular files
* we created
*/
if (artyp != ISREG)
can_unlnk = 0;
/*
* if we are writing, we are done
*/
if (act == ARCHIVE) {
blksz = rdblksz = wrblksz;
lstrval = 1;
return 0;
}
/*
* set default blksz on read. APPNDs writes rdblksz on the last volume
* On all new archive volumes, we shift to wrblksz (if the user
* specified one, otherwize we will continue to use rdblksz). We
* must set blocksize based on what kind of device the archive is
* stored.
*/
switch(artyp) {
#ifdef SUPPORT_TAPE
case ISTAPE:
/*
* Tape drives come in at least two flavors. Those that support
* variable sized records and those that have fixed sized
* records. They must be treated differently. For tape drives
* that support variable sized records, we must make large
* reads to make sure we get the entire record, otherwise we
* will just get the first part of the record (up to size we
* asked). Tapes with fixed sized records may or may not return
* multiple records in a single read. We really do not care
* what the physical record size is UNLESS we are going to
* append. (We will need the physical block size to rewrite
* the trailer). Only when we are appending do we go to the
* effort to figure out the true PHYSICAL record size.
*/
blksz = rdblksz = MAXBLK;
break;
#endif /* SUPPORT_TAPE */
case ISPIPE:
case ISBLK:
case ISCHR:
/*
* Blocksize is not a major issue with these devices (but must
* be kept a multiple of 512). If the user specified a write
* block size, we use that to read. Under append, we must
* always keep blksz == rdblksz. Otherwise we go ahead and use
* the device optimal blocksize as (and if) returned by stat
* and if it is within pax specs.
*/
if ((act == APPND) && wrblksz) {
blksz = rdblksz = wrblksz;
break;
}
if ((arsb.st_blksize > 0) && (arsb.st_blksize < MAXBLK) &&
((arsb.st_blksize % BLKMULT) == 0))
rdblksz = arsb.st_blksize;
else
rdblksz = DEVBLK;
/*
* For performance go for large reads when we can without harm
*/
if ((act == APPND) || (artyp == ISCHR))
blksz = rdblksz;
else
blksz = MAXBLK;
break;
case ISREG:
/*
* if the user specified wrblksz works, use it. Under appends
* we must always keep blksz == rdblksz
*/
if ((act == APPND) && wrblksz && ((arsb.st_size%wrblksz)==0)){
blksz = rdblksz = wrblksz;
break;
}
/*
* See if we can find the blocking factor from the file size
*/
for (rdblksz = MAXBLK; rdblksz > 0; rdblksz -= BLKMULT)
if ((arsb.st_size % rdblksz) == 0)
break;
/*
* When we cannot find a match, we may have a flawed archive.
*/
if (rdblksz <= 0)
rdblksz = FILEBLK;
/*
* for performance go for large reads when we can
*/
if (act == APPND)
blksz = rdblksz;
else
blksz = MAXBLK;
break;
default:
/*
* should never happen, worst case, slow...
*/
blksz = rdblksz = BLKMULT;
break;
}
lstrval = 1;
return 0;
}
/*
* ar_close()
* closes archive device, increments volume number, and prints i/o summary
*/
void
ar_close(void)
{
int status;
if (arfd < 0) {
did_io = io_ok = flcnt = 0;
return;
}
#ifdef SUPPORT_TAPE
/*
* Close archive file. This may take a LONG while on tapes (we may be
* forced to wait for the rewind to complete) so tell the user what is
* going on (this avoids the user hitting control-c thinking pax is
* broken).
*/
if (vflag && (artyp == ISTAPE)) {
if (vfpart)
(void)putc('\n', listf);
(void)fprintf(listf,
"%s: Waiting for tape drive close to complete...",
argv0);
(void)fflush(listf);
}
#endif /* SUPPORT_TAPE */
/*
* if nothing was written to the archive (and we created it), we remove
* it
*/
if (can_unlnk && (fstat(arfd, &arsb) == 0) && (S_ISREG(arsb.st_mode)) &&
(arsb.st_size == 0)) {
(void)unlink(arcname);
can_unlnk = 0;
}
/*
* for a quick extract/list, pax frequently exits before the child
* process is done
*/
if ((act == LIST || act == EXTRACT) && nflag && zpid > 0)
kill(zpid, SIGINT);
#ifdef SUPPORT_RMT
if (artyp == ISRMT)
(void)rmtclose(arfd);
else
#endif /* SUPPORT_RMT */
(void)close(arfd);
/* Do not exit before child to ensure data integrity */
if (zpid > 0)
waitpid(zpid, &status, 0);
#ifdef SUPPORT_TAPE
if (vflag && (artyp == ISTAPE)) {
(void)fputs("done.\n", listf);
vfpart = 0;
(void)fflush(listf);
}
#endif /* SUPPORT_TAPE */
arfd = -1;
if (!io_ok && !did_io) {
flcnt = 0;
return;
}
did_io = io_ok = 0;
/*
* The volume number is only increased when the last device has data
* and we have already determined the archive format.
*/
if (frmt != NULL)
++arvol;
if (!vflag) {
flcnt = 0;
return;
}
/*
* Print out a summary of I/O for this archive volume.
*/
if (vfpart) {
(void)putc('\n', listf);
vfpart = 0;
}
/*
* If we have not determined the format yet, we just say how many bytes
* we have skipped over looking for a header to id. there is no way we
* could have written anything yet.
*/
if (frmt == NULL) {
(void)fprintf(listf, "%s: unknown format, " OFFT_F
" bytes skipped.\n", argv0, rdcnt);
(void)fflush(listf);
flcnt = 0;
return;
}
if (strcmp(NM_CPIO, argv0) == 0) {
(void)fprintf(listf, OFFT_F " blocks\n",
(rdcnt ? rdcnt : wrcnt) / 5120);
}
ar_summary(0);
(void)fflush(listf);
flcnt = 0;
}
/*
* ar_drain()
* drain any archive format independent padding from an archive read
* from a socket or a pipe. This is to prevent the process on the
* other side of the pipe from getting a SIGPIPE (pax will stop
* reading an archive once a format dependent trailer is detected).
*/
void
ar_drain(void)
{
int res;
char drbuf[MAXBLK];
/*
* we only drain from a pipe/socket. Other devices can be closed
* without reading up to end of file. We sure hope that pipe is closed
* on the other side so we will get an EOF.
*/
if ((artyp != ISPIPE) || (lstrval <= 0))
return;
/*
* keep reading until pipe is drained
*/
#ifdef SUPPORT_RMT
if (artyp == ISRMT) {
while ((res = rmtread_with_restart(arfd,
drbuf, sizeof(drbuf))) > 0)
continue;
} else {
#endif /* SUPPORT_RMT */
while ((res = read_with_restart(arfd,
drbuf, sizeof(drbuf))) > 0)
continue;
#ifdef SUPPORT_RMT
}
#endif /* SUPPORT_RMT */
lstrval = res;
}
/*
* ar_set_wr()
* Set up device right before switching from read to write in an append.
* device dependent code (if required) to do this should be added here.
* For all archive devices we are already positioned at the place we want
* to start writing when this routine is called.
* Return:
* 0 if all ready to write, -1 otherwise
*/
int
ar_set_wr(void)
{
off_t cpos;
/*
* we must make sure the trailer is rewritten on append, ar_next()
* will stop us if the archive containing the trailer was not written
*/
wr_trail = 0;
/*
* Add any device dependent code as required here
*/
if (artyp != ISREG)
return 0;
/*
* Ok we have an archive in a regular file. If we were rewriting a
* file, we must get rid of all the stuff after the current offset
* (it was not written by pax).
*/
if (((cpos = lseek(arfd, (off_t)0L, SEEK_CUR)) < 0) ||
(ftruncate(arfd, cpos) < 0)) {
syswarn(1, errno, "Unable to truncate archive file");
return -1;
}
return 0;
}
/*
* ar_app_ok()
* check if the last volume in the archive allows appends. We cannot check
* this until we are ready to write since there is no spec that says all
* volumes in a single archive have to be of the same type...
* Return:
* 0 if we can append, -1 otherwise.
*/
int
ar_app_ok(void)
{
if (artyp == ISPIPE) {
tty_warn(1,
"Cannot append to an archive obtained from a pipe.");
return -1;
}
if (!invld_rec)
return 0;
tty_warn(1,
"Cannot append, device record size %d does not support %s spec",
rdblksz, argv0);
return -1;
}
#ifdef SYS_NO_RESTART
/*
* read_with_restart()
* Equivalent to read() but does retry on signals.
* This function is not needed on 4.2BSD and later.
* Return:
* Number of bytes written. -1 indicates an error.
*/
int
read_with_restart(int fd, void *buf, int bsz)
{
int r;
while (((r = read(fd, buf, bsz)) < 0) && errno == EINTR)
continue;
return(r);
}
/*
* rmtread_with_restart()
* Equivalent to rmtread() but does retry on signals.
* This function is not needed on 4.2BSD and later.
* Return:
* Number of bytes written. -1 indicates an error.
*/
static int
rmtread_with_restart(int fd, void *buf, int bsz)
{
int r;
while (((r = rmtread(fd, buf, bsz)) < 0) && errno == EINTR)
continue;
return(r);
}
#endif
/*
* xread()
* Equivalent to read() but does retry on partial read, which may occur
* on signals.
* Return:
* Number of bytes read. 0 for end of file, -1 for an error.
*/
int
xread(int fd, void *buf, int bsz)
{
char *b = buf;
int nread = 0;
int r;
do {
#ifdef SUPPORT_RMT
if ((r = rmtread_with_restart(fd, b, bsz)) <= 0)
break;
#else
if ((r = read_with_restart(fd, b, bsz)) <= 0)
break;
#endif /* SUPPORT_RMT */
b += r;
bsz -= r;
nread += r;
} while (bsz > 0);
return(nread ? nread : r);
}
#ifdef SYS_NO_RESTART
/*
* write_with_restart()
* Equivalent to write() but does retry on signals.
* This function is not needed on 4.2BSD and later.
* Return:
* Number of bytes written. -1 indicates an error.
*/
int
write_with_restart(int fd, void *buf, int bsz)
{
int r;
while (((r = write(fd, buf, bsz)) < 0) && errno == EINTR)
;
return(r);
}
/*
* rmtwrite_with_restart()
* Equivalent to write() but does retry on signals.
* This function is not needed on 4.2BSD and later.
* Return:
* Number of bytes written. -1 indicates an error.
*/
static int
rmtwrite_with_restart(int fd, void *buf, int bsz)
{
int r;
while (((r = rmtwrite(fd, buf, bsz)) < 0) && errno == EINTR)
;
return(r);
}
#endif
/*
* xwrite()
* Equivalent to write() but does retry on partial write, which may occur
* on signals.
* Return:
* Number of bytes written. -1 indicates an error.
*/
int
xwrite(int fd, void *buf, int bsz)
{
char *b = buf;
int written = 0;
int r;
do {
#ifdef SUPPORT_RMT
if ((r = rmtwrite_with_restart(fd, b, bsz)) <= 0)
break;
#else
if ((r = write_with_restart(fd, b, bsz)) <= 0)
break;
#endif /* SUPPORT_RMT */
b += r;
bsz -= r;
written += r;
} while (bsz > 0);
return(written ? written : r);
}
/*
* ar_read()
* read up to a specified number of bytes from the archive into the
* supplied buffer. When dealing with tapes we may not always be able to
* read what we want.
* Return:
* Number of bytes in buffer. 0 for end of file, -1 for a read error.
*/
int
ar_read(char *buf, int cnt)
{
int res = 0;
/*
* if last i/o was in error, no more reads until reset or new volume
*/
if (lstrval <= 0)
return(lstrval);
/*
* how we read must be based on device type
*/
switch (artyp) {
#ifdef SUPPORT_RMT
case ISRMT:
if ((res = rmtread_with_restart(arfd, buf, cnt)) > 0) {
io_ok = 1;
return res;
}
break;
#endif /* SUPPORT_RMT */
#ifdef SUPPORT_TAPE
case ISTAPE:
if ((res = read_with_restart(arfd, buf, cnt)) > 0) {
/*
* CAUTION: tape systems may not always return the same
* sized records so we leave blksz == MAXBLK. The
* physical record size that a tape drive supports is
* very hard to determine in a uniform and portable
* manner.
*/
io_ok = 1;
if (res != rdblksz) {
/*
* Record size changed. If this happens on
* any record after the first, we probably have
* a tape drive which has a fixed record size
* (we are getting multiple records in a single
* read). Watch out for record blocking that
* violates pax spec (must be a multiple of
* BLKMULT).
*/
rdblksz = res;
if (rdblksz % BLKMULT)
invld_rec = 1;
}
return(res);
}
break;
#endif /* SUPPORT_TAPE */
case ISREG:
case ISBLK:
case ISCHR:
case ISPIPE:
default:
/*
* Files are so easy to deal with. These other things cannot
* be trusted at all. So when we are dealing with character
* devices and pipes we just take what they have ready for us
* and return. Trying to do anything else with them runs the
* risk of failure.
*/
if ((res = read_with_restart(arfd, buf, cnt)) > 0) {
io_ok = 1;
return(res);
}
break;
}
/*
* We are in trouble at this point, something is broken...
*/
lstrval = res;
if (res < 0)
syswarn(1, errno, "Failed read on archive volume %d", arvol);
else
tty_warn(0, "End of archive volume %d reached", arvol);
return(res);
}
/*
* ar_write()
* Write a specified number of bytes in supplied buffer to the archive
* device so it appears as a single "block". Deals with errors and tries
* to recover when faced with short writes.
* Return:
* Number of bytes written. 0 indicates end of volume reached and with no
* flaws (as best that can be detected). A -1 indicates an unrecoverable
* error in the archive occurred.
*/
int
ar_write(char *buf, int bsz)
{
int res;
off_t cpos;
/*
* do not allow pax to create a "bad" archive. Once a write fails on
* an archive volume prevent further writes to it.
*/
if (lstrval <= 0)
return(lstrval);
if ((res = xwrite(arfd, buf, bsz)) == bsz) {
wr_trail = 1;
io_ok = 1;
return(bsz);
}
/*
* write broke, see what we can do with it. We try to send any partial
* writes that may violate pax spec to the next archive volume.
*/
if (res < 0)
lstrval = res;
else
lstrval = 0;
switch (artyp) {
case ISREG:
if ((res > 0) && (res % BLKMULT)) {
/*
* try to fix up partial writes which are not BLKMULT
* in size by forcing the runt record to next archive
* volume
*/
if ((cpos = lseek(arfd, (off_t)0L, SEEK_CUR)) < 0)
break;
cpos -= (off_t)res;
if (ftruncate(arfd, cpos) < 0)
break;
res = lstrval = 0;
break;
}
if (res >= 0)
break;
/*
* if file is out of space, handle it like a return of 0
*/
if ((errno == ENOSPC) || (errno == EFBIG))
res = lstrval = 0;
#ifdef EDQUOT
if (errno == EDQUOT)
res = lstrval = 0;
#endif
break;
#ifdef SUPPORT_TAPE
case ISTAPE:
#endif /* SUPPORT_TAPE */
case ISCHR:
case ISBLK:
#ifdef SUPPORT_RMT
case ISRMT:
#endif /* SUPPORT_RMT */
if (res >= 0)
break;
if (errno == EACCES) {
tty_warn(0,
"Write failed, archive is write protected.");
res = lstrval = 0;
return 0;
}
/*
* see if we reached the end of media, if so force a change to
* the next volume
*/
if ((errno == ENOSPC) || (errno == EIO) || (errno == ENXIO))
res = lstrval = 0;
break;
case ISPIPE:
default:
/*
* we cannot fix errors to these devices
*/
break;
}
/*
* Better tell the user the bad news...
* if this is a block aligned archive format, we may have a bad archive
* if the format wants the header to start at a BLKMULT boundary. While
* we can deal with the mis-aligned data, it violates spec and other
* archive readers will likely fail. if the format is not block
* aligned, the user may be lucky (and the archive is ok).
*/
if (res >= 0) {
if (res > 0)
wr_trail = 1;
io_ok = 1;
}
/*
* If we were trying to rewrite the trailer and it didn't work, we
* must quit right away.
*/
if (!wr_trail && (res <= 0)) {
tty_warn(1,
"Unable to append, trailer re-write failed. Quitting.");
return(res);
}
if (res == 0)
tty_warn(0, "End of archive volume %d reached", arvol);
else if (res < 0)
syswarn(1, errno, "Failed write to archive volume: %d", arvol);
else if (!frmt->blkalgn || ((res % frmt->blkalgn) == 0))
tty_warn(0,
"WARNING: partial archive write. Archive MAY BE FLAWED");
else
tty_warn(1,"WARNING: partial archive write. Archive IS FLAWED");
return(res);
}
/*
* ar_rdsync()
* Try to move past a bad spot on a flawed archive as needed to continue
* I/O. Clears error flags to allow I/O to continue.
* Return:
* 0 when ok to try i/o again, -1 otherwise.
*/
int
ar_rdsync(void)
{
long fsbz;