/*
* read the current tape position
*/
static int
GetTapePos(long long *pos)
{
int err = 0;
#ifdef RDUMP
if (host) {
*pos = (long long) rmtseek((off_t)0, (int)LSEEK_GET_TAPEPOS);
err = *pos < 0;
}
else
#endif
{
if (magtapeout) {
long mtpos;
*pos = 0;
err = (ioctl(tapefd, MTIOCPOS, &mtpos) < 0);
*pos = (long long)mtpos;
}
else {
*pos = lseek(tapefd, 0, SEEK_CUR);
err = (*pos < 0);
}
}
if (err) {
err = errno;
msg("[%ld] error: %d (getting tapepos: %lld)\n", getpid(),
err, *pos);
return err;
}
return err;
}
/*
* 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++;
}
