Date: Thu, 29 Apr 1999 11:08:24 -0500 (CDT) From: dkelly@hiwaay.net To: FreeBSD-gnats-submit@freebsd.org Subject: bin/11386: some small tcopy enhancements Message-ID: <199904291608.LAA53852@nospam.hiwaay.net>
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>Number: 11386
>Category: bin
>Synopsis: counter sizes and file rewind
>Confidential: no
>Severity: non-critical
>Priority: medium
>Responsible: freebsd-bugs
>State: open
>Quarter:
>Keywords:
>Date-Required:
>Class: change-request
>Submitter-Id: current-users
>Arrival-Date: Thu Apr 29 09:10:01 PDT 1999
>Closed-Date:
>Last-Modified:
>Originator: David Kelly
>Release: FreeBSD 3.1-STABLE i386
>Organization:
n/a
>Environment:
FreeBSD nospam.hiwaay.net 3.1-STABLE FreeBSD 3.1-STABLE #8: Wed Apr 14 20:36:28 CDT 1999 dkelly@nospam.hiwaay.net:/usr/src/sys/compile/REEBOK i386
>Description:
Tcopy uses 32 bit unsigned to accumulate a count of bytes read/written.
That doesn't work well for tapes over 4G.
I use tcopy a lot to write images of a tape to tape as tape to tape
copying is terribly slow. Slower than it should be. Quickly found out
tcopy can not rewind a file when doing copy/verify.
>How-To-Repeat:
Tcopy a tape larger than 4g.
tcopy -c file1 file2 --> this will produce an ioctl() error on rewind.
>Fix:
The following diffs correct the source and manpage:
% diff -ruN tcopy.c.orig tcopy.c
--- tcopy.c.orig Sun Mar 8 07:36:24 1998
+++ tcopy.c Mon Apr 5 16:37:45 1999
@@ -65,7 +65,7 @@
#define NOCOUNT (-2)
int filen, guesslen, maxblk = MAXREC;
-u_long lastrec, record, size, tsize;
+u_int64_t lastrec, record, size, tsize;
FILE *msg = stdout;
void *getspace __P((int));
@@ -73,6 +73,7 @@
static void usage __P((void));
void verify __P((int, int, char *));
void writeop __P((int, int));
+void rewind_tape(int);
int
main(argc, argv)
@@ -156,16 +157,16 @@
if (nread >= 0)
goto r1;
}
- err(1, "read error, file %d, record %ld", filen, record);
+ err(1, "read error, file %d, record %qu", filen, record);
} else if (nread != lastnread) {
if (lastnread != 0 && lastnread != NOCOUNT) {
if (lastrec == 0 && nread == 0)
- fprintf(msg, "%ld records\n", record);
+ fprintf(msg, "%qu records\n", record);
else if (record - lastrec > 1)
- fprintf(msg, "records %ld to %ld\n",
+ fprintf(msg, "records %qu to %qu\n",
lastrec, record);
else
- fprintf(msg, "record %ld\n", lastrec);
+ fprintf(msg, "record %qu\n", lastrec);
}
if (nread != 0)
fprintf(msg, "file %d: block size %d: ",
@@ -183,9 +184,9 @@
nw = write(outp, buff, nread);
if (nw != nread) {
if (nw == -1) {
- warn("write error, file %d, record %ld", filen, record);
+ warn("write error, file %d, record %qu", filen, record);
} else {
- warnx("write error, file %d, record %ld", filen, record);
+ warnx("write error, file %d, record %qu", filen, record);
warnx("write (%d) != read (%d)", nw, nread);
}
errx(5, "copy aborted");
@@ -199,7 +200,7 @@
break;
}
fprintf(msg,
- "file %d: eof after %lu records: %lu bytes\n",
+ "file %d: eof after %qu records: %qu bytes\n",
filen, record, size);
needeof = 1;
filen++;
@@ -209,14 +210,14 @@
}
lastnread = nread;
}
- fprintf(msg, "total length: %lu bytes\n", tsize);
+ fprintf(msg, "total length: %qu bytes\n", tsize);
(void)signal(SIGINT, oldsig);
if (op == COPY || op == COPYVERIFY) {
writeop(outp, MTWEOF);
writeop(outp, MTWEOF);
if (op == COPYVERIFY) {
- writeop(outp, MTREW);
- writeop(inp, MTREW);
+ rewind_tape(outp);
+ rewind_tape(inp);
verify(inp, outp, buff);
}
}
@@ -283,10 +284,10 @@
{
if (record)
if (record - lastrec > 1)
- fprintf(msg, "records %ld to %ld\n", lastrec, record);
+ fprintf(msg, "records %qu to %qu\n", lastrec, record);
else
- fprintf(msg, "record %ld\n", lastrec);
- fprintf(msg, "interrupt at file %d: record %ld\n", filen, record);
+ fprintf(msg, "record %qu\n", lastrec);
+ fprintf(msg, "interrupt at file %d: record %qu\n", filen, record);
fprintf(msg, "total length: %ld bytes\n", tsize + size);
exit(1);
}
@@ -319,4 +320,23 @@
{
fprintf(stderr, "usage: tcopy [-cvx] [-s maxblk] [src [dest]]\n");
exit(1);
+}
+
+void
+rewind_tape(int fd)
+{
+ struct stat sp;
+
+ if(fstat(fd, &sp))
+ errx(12, "fstat in rewind");
+
+ /*
+ * don't want to do tape ioctl on regular files:
+ */
+ if( S_ISREG(sp.st_mode) ) {
+ if( lseek(fd, 0, SEEK_SET) == -1 )
+ errx(13, "lseek");
+ } else
+ /* assume its a tape */
+ writeop(fd, MTREW);
}
% diff -ruN tcopy.1.orig tcopy.1
--- tcopy.1.orig Fri Feb 12 15:26:42 1999
+++ tcopy.1 Thu Apr 29 09:54:17 1999
@@ -87,3 +87,19 @@
.Nm
command appeared in
.Bx 4.3 .
+.Sh BUGS
+Writting an image of a tape to a file does not preserve much more than
+the raw data. Block size(s) and tape EOF marks are lost which would
+otherwise be preserved in a tape-to-tape copy.
+
+EOD is determined by two sequential EOF marks with no data between.
+There are old systems which typically wrote three EOF's between tape
+files.
+.Xr tcopy 1
+will erroneously stop copying early in this case.
+
+When using the copy/verify option \-c
+.Xr tcopy 1
+does not rewind the tapes prior to start. A rewind is performed
+after writing prior to the verification stage. If one doesn't start
+at BOT then the comparison may not be of the intended data.
>Release-Note:
>Audit-Trail:
>Unformatted:
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