static void
findtapeblksize(void)
{
long i;
for (i = 0; i < ntrec; i++)
((struct s_spcl *)&tapebuf[i * TP_BSIZE])->c_magic = 0;
blkcnt = 0;
#ifdef RRESTORE
if (host)
i = rmtread(tapebuf, ntrec * TP_BSIZE);
else
#endif
i = read(mt, tapebuf, ntrec * TP_BSIZE);
if (i <= 0) {
fprintf(stderr, "tape read error: %s\n", strerror(errno));
done(1);
}
if (i % TP_BSIZE != 0) {
fprintf(stderr, "Tape block size (%ld) %s (%d)\n",
i, "is not a multiple of dump block size", TP_BSIZE);
done(1);
}
ntrec = i / TP_BSIZE;
numtrec = ntrec;
vprintf(stdout, "Tape block size is %ld\n", ntrec);
}
static void
findtapeblksize(void)
{
long i;
for (i = 0; i < ntrec; i++)
((struct s_spcl *)&tapebuf[i * TP_BSIZE])->c_magic = 0;
blkcnt = 0;
#ifdef RRESTORE
if (host)
i = rmtread(tapebuf, ntrec * TP_BSIZE);
else
#endif
i = read(mt, tapebuf, ntrec * TP_BSIZE);
if (i <= 0)
err(1, "tape read error");
if (i % TP_BSIZE != 0) {
errx(1,
"Tape block size (%ld) is not a multiple of dump block size (%d)",
i, TP_BSIZE);
}
ntrec = i / TP_BSIZE;
numtrec = ntrec;
Vprintf(stdout, "Tape block size is %ld\n", ntrec);
}
/*
* 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;
}
/*
* Read TP_BSIZE blocks from the input.
* Handle read errors, and end of media.
*/
static void
readtape(char *buf)
{
long rd, newvol, i, oldnumtrec;
int cnt, seek_failed;
if (blkcnt + (byteslide > 0) < numtrec) {
memmove(buf, &tapebuf[(blkcnt++ * TP_BSIZE) + byteslide], (long)TP_BSIZE);
blksread++;
tapeaddr++;
return;
}
if (numtrec > 0)
memmove(&tapebuf[-TP_BSIZE],
&tapebuf[(numtrec-1) * TP_BSIZE], (long)TP_BSIZE);
oldnumtrec = numtrec;
for (i = 0; i < ntrec; i++)
((struct s_spcl *)&tapebuf[i * TP_BSIZE])->c_magic = 0;
if (numtrec == 0)
numtrec = ntrec;
cnt = ntrec * TP_BSIZE;
rd = 0;
getmore:
#ifdef RRESTORE
if (host)
i = rmtread(&tapebuf[rd], cnt);
else
#endif
i = read(mt, &tapebuf[rd], cnt);
/*
* Check for mid-tape short read error.
* If found, skip rest of buffer and start with the next.
*/
if (!pipein && !pipecmdin && numtrec < ntrec && i > 0) {
dprintf(stdout, "mid-media short read error.\n");
numtrec = ntrec;
}
/*
* Handle partial block read.
*/
if ((pipein || pipecmdin) && i == 0 && rd > 0)
i = rd;
else if (i > 0 && i != ntrec * TP_BSIZE) {
if (pipein || pipecmdin) {
rd += i;
cnt -= i;
if (cnt > 0)
goto getmore;
i = rd;
} else {
/*
* Short read. Process the blocks read.
*/
if (i % TP_BSIZE != 0)
vprintf(stdout,
"partial block read: %ld should be %ld\n",
i, ntrec * TP_BSIZE);
numtrec = i / TP_BSIZE;
}
}
/*
* Handle read error.
*/
if (i < 0) {
fprintf(stderr, "Tape read error while ");
switch (curfile.action) {
default:
fprintf(stderr, "trying to set up tape\n");
break;
case UNKNOWN:
fprintf(stderr, "trying to resynchronize\n");
break;
case USING:
fprintf(stderr, "restoring %s\n", curfile.name);
break;
case SKIP:
fprintf(stderr, "skipping over inode %ju\n",
(uintmax_t)curfile.ino);
break;
}
if (!yflag && !reply("continue"))
done(1);
i = ntrec * TP_BSIZE;
memset(tapebuf, 0, i);
#ifdef RRESTORE
if (host)
seek_failed = (rmtseek(i, 1) < 0);
else
#endif
seek_failed = (lseek(mt, i, SEEK_CUR) == (off_t)-1);
if (seek_failed) {
fprintf(stderr,
"continuation failed: %s\n", strerror(errno));
done(1);
}
}
/*
* Handle end of tape.
*/
if (i == 0) {
vprintf(stdout, "End-of-tape encountered\n");
if (!pipein) {
newvol = volno + 1;
volno = 0;
numtrec = 0;
getvol(newvol);
readtape(buf);
return;
}
if (rd % TP_BSIZE != 0)
panic("partial block read: %ld should be %ld\n",
rd, ntrec * TP_BSIZE);
terminateinput();
memmove(&tapebuf[rd], &endoftapemark, (long)TP_BSIZE);
}
if (oldnumtrec == 0)
blkcnt = 0;
else
blkcnt -= oldnumtrec;
memmove(buf,
&tapebuf[(blkcnt++ * TP_BSIZE) + byteslide], (long)TP_BSIZE);
blksread++;
tapeaddr++;
}
/* Set ARCHIVE for uncompressing, then reading an archive. */
pid_t
sys_child_open_for_uncompress (void)
{
int parent_pipe[2];
int child_pipe[2];
pid_t grandchild_pid;
pid_t child_pid;
xpipe (parent_pipe);
child_pid = xfork ();
if (child_pid > 0)
{
/* The parent tar is still here! Just clean up. */
archive = parent_pipe[PREAD];
xclose (parent_pipe[PWRITE]);
return child_pid;
}
/* The newborn child tar is here! */
set_program_name (_("tar (child)"));
signal (SIGPIPE, SIG_DFL);
xdup2 (parent_pipe[PWRITE], STDOUT_FILENO);
xclose (parent_pipe[PREAD]);
/* Check if we need a grandchild tar. This happens only if either:
a) we're reading stdin: to force unblocking;
b) the file is to be accessed by rmt: compressor doesn't know how;
c) the file is not a plain file. */
if (strcmp (archive_name_array[0], "-") != 0
&& !_remdev (archive_name_array[0])
&& is_regular_file (archive_name_array[0]))
{
/* We don't need a grandchild tar. Open the archive and lauch the
uncompressor. */
archive = open (archive_name_array[0], O_RDONLY | O_BINARY, MODE_RW);
if (archive < 0)
open_fatal (archive_name_array[0]);
xdup2 (archive, STDIN_FILENO);
execlp (use_compress_program_option, use_compress_program_option,
"-d", (char *) 0);
exec_fatal (use_compress_program_option);
}
/* We do need a grandchild tar. */
xpipe (child_pipe);
grandchild_pid = xfork ();
if (grandchild_pid == 0)
{
/* The newborn grandchild tar is here! Launch the uncompressor. */
set_program_name (_("tar (grandchild)"));
xdup2 (child_pipe[PREAD], STDIN_FILENO);
xclose (child_pipe[PWRITE]);
execlp (use_compress_program_option, use_compress_program_option,
"-d", (char *) 0);
exec_fatal (use_compress_program_option);
}
/* The child tar is still here! */
/* Prepare for unblocking the data from the archive into the
uncompressor. */
xdup2 (child_pipe[PWRITE], STDOUT_FILENO);
xclose (child_pipe[PREAD]);
if (strcmp (archive_name_array[0], "-") == 0)
archive = STDIN_FILENO;
else
archive = rmtopen (archive_name_array[0], O_RDONLY | O_BINARY,
MODE_RW, rsh_command_option);
if (archive < 0)
open_fatal (archive_name_array[0]);
/* Let's read the archive and pipe it into stdout. */
while (1)
{
char *cursor;
size_t maximum;
size_t count;
size_t status;
clear_read_error_count ();
error_loop:
status = rmtread (archive, record_start->buffer, record_size);
if (status == SAFE_READ_ERROR)
{
archive_read_error ();
goto error_loop;
}
if (status == 0)
break;
cursor = record_start->buffer;
maximum = status;
while (maximum)
{
count = maximum < BLOCKSIZE ? maximum : BLOCKSIZE;
if (full_write (STDOUT_FILENO, cursor, count) != count)
write_error (use_compress_program_option);
cursor += count;
maximum -= count;
}
}
xclose (STDOUT_FILENO);
wait_for_grandchild (grandchild_pid);
}