Initial import of fdread(1), a logical counterpart to fdwrite(1).

Its main purpose is to adapt automatically to the floppy parameters
(in particular the track size for efficient reading), and to allow a
simple error recovery for CRC-errored sectors.  Requires the newly
added fdc(4) options.

3 files changed, 497 insertions, 0 deletions

diff --git a/usr.sbin/fdread/Makefile b/usr.sbin/fdread/Makefile
new file mode 100644
index 0000000..8d62a43
--- /dev/null
+++ b/usr.sbin/fdread/Makefile
@@ -0,0 +1,6 @@
+# $FreeBSD$
+
+PROG=	fdread
+CFLAGS+=-Wall
+
+.include <bsd.prog.mk>
diff --git a/usr.sbin/fdread/fdread.1 b/usr.sbin/fdread/fdread.1
new file mode 100644
index 0000000..7e21404
--- /dev/null
+++ b/usr.sbin/fdread/fdread.1
@@ -0,0 +1,184 @@
+.\"
+.\" Copyright (c) 2001 Joerg Wunsch
+.\"
+.\" All rights reserved.
+.\"
+.\" 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.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``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 DEVELOPERS 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.
+.\"
+.\" $FreeBSD$
+.\"
+.\"
+.Dd May 14, 2001
+.Os FreeBSD
+.Dt FDREAD 1
+.Sh NAME
+.Nm fdread
+.Nd read floppy disks
+.Sh SYNOPSIS
+.Nm
+.Op Fl q
+.Op Fl r
+.Op Fl d Ar device
+.Op Fl f Ar fillbyte
+.Op Fl o Ar file
+.Sh DESCRIPTION
+.Nm Fdread
+reads floppy disks.  Effective read blocking based on the track
+size is performed, and floppy-specific error recovery of otherwise
+bad blocks can be enabled.
+.Pp
+.Nm Fdread
+will always read an entire floppy medium, and write its contents to
+the respective output file.  Unlike other tools like
+.Xr dd 1 ,
+.Nm
+automatically uses a read block size that is more efficient than
+reading single blocks (usually one track of data at a time), but
+falls back to reading single floppy sectors in case of an input/output
+error occurred, in order to obtain as much valid data as possible.
+While
+.Nm
+is working, kernel error reporting for floppy errors is turned off, so
+the console and/or syslog are not flooded with kernel error messages.
+.Sh Options
+The options are as follows:
+.Bl -tag -width XXXX -offset indent
+.It Fl q
+Turn on quiet mode.  By default, the medium parameters of the device
+are being written to standard error output, progress will be indicated
+by the approximate number of kilobytes read so far, and errors will be
+printed out in detail, including the information about the location of
+recovered data in the output.  In quiet mode, none of these messages
+will be generated.
+.It Fl r
+Enable error recovery.  By default,
+.Nm
+stops after the first unrecovered read error, much like
+.Xr dd 1
+does.  In recovery mode, however, one of two recovery actions will be
+taken:
+.Bl -bullet -offset indent
+.It
+If the error was a CRC error in the data field, the
+kernel is told to ignore the error, and data are transferred to the
+output file anyway.
+.Em Note that this will cause the erroneous data
+.Em to be included in the output file !
+Still, this is the best recovery action that can be taken at all.
+.It
+All other errors are really fatal (usually, the FDC didn't find the
+sector ID fields), thus a dummy block with fill
+bytes will be included in the output file.
+.El
+.Pp
+Unless operating in quiet mode, the action taken and the location of
+the error in the output file will be displayed.
+.It Fl d Ar device
+Specify the input floppy device, defaulting to
+.Pa /dev/fd0 .
+The parameter
+.Ar device
+must be a valid floppy disk device.
+.It Fl f Ar fillbyte
+Value of the fill byte used for dummy blocks in the output file in
+recovery mode.  Defaults to
+.Ql 0xf0 .
+(Mnemonic:
+.Dq foo . )
+The value can be specified using the usual C language notation of
+the number base.
+.It Fl o Ar file
+Specify the output file to be
+.Ar file .
+By default, the data will be written to standard output.
+.El
+.Sh FILES
+.Bl -tag -width XXXXXXXX -offset indent
+.It Pa /dev/fd0
+Default device to read from.
+.Sh DIAGNOSTICS
+.Nm Fdread
+sets the exit value according to
+.Xr sysexits 3 .
+In recovery mode, the exit value will be set to
+.Sy EX_IOERR
+if any error occurred during processing (even in quiet mode).
+.Pp
+Unless running in quiet mode, upon encountering an error, the status
+of the floppy disc controller (FDC) will be printed out, both in
+hexadecimal form, followed by a textual description that translates
+those values into a human-readable form for the most common error
+cases that can happen in a PC environment.
+.Pp
+The FDC error status includes the three FDC status registers
+.Ql ST0 ,
+.Ql ST1 ,
+and
+.Ql ST2 ,
+as well as the location of the error (physical cylinder, head, and sector
+number, plus the
+.Dq sector shift value ,
+respectively).  See the manual for the NE765 or compatible for details
+about the status register contents.
+.Pp
+The FDC's status is then examined to determine whether the error is
+deemed to be recoverable.  If error recovery was requested, the
+location of the bad block in the output file is indicated by its
+(hexadecimal) bounds.  Also, a summary line indicating the total number
+of transfer errors will be printed before exiting.
+.Sh SEE ALSO
+.Xr dd 1 ,
+.Xr fdc 4 ,
+.Xr fdcontrol 8 ,
+.Xr fdwrite 1 ,
+.Xr sysexits 3
+.Sh HISTORY
+.Nm Fdread
+was written mainly to provide a means of recovering at least some of
+the data on bad media, and to obviate the need to invoke
+.Xr dd 1
+with too many hard to memorize options that might be useful to handle
+a floppy.
+.Pp
+The command appeared in
+.Fx 5.0 .
+.Sh AUTHORS
+Program and man page by
+.ie t J\(:org Wunsch.
+.el Joerg Wunsch.
+.Sh BUGS
+Concurrent traffic on the second floppy drive located at the same FDC
+will make error recovery attempts pointless, since the FDC status
+obtained after a read error occurred cannot be guaranteed to actually
+belong to the erroneous transfer.  Thus using option
+.Fl r
+is only reliable if
+.Ar device
+is the only active drive on that controller.
+.Pp
+No attempt beyond the floppy error retry mechanism of
+.Xr fdc 4
+is made in order to see whether bad sectors could still be read
+without errors by trying multiple times.
+.Pp
+Bits that are (no longer) available on the floppy medium cannot be
+guessed by
+.Nm fdread .
diff --git a/usr.sbin/fdread/fdread.c b/usr.sbin/fdread/fdread.c
new file mode 100644
index 0000000..bb75841
--- /dev/null
+++ b/usr.sbin/fdread/fdread.c
@@ -0,0 +1,307 @@
+/*
+ * Copyright (c) 2001 Joerg Wunsch
+ *
+ * All rights reserved.
+ *
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``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 DEVELOPERS 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.
+ *
+ * $FreeBSD$
+ */
+
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#include <machine/ioctl_fd.h>
+
+#include <err.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <paths.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sysexits.h>
+#include <unistd.h>
+
+/* XXX -- header file should probably be installed somewhere */
+#include "/sys/isa/ic/nec765.h"
+
+int	quiet, recover;
+unsigned char fillbyte = 0xf0;	/* "foo" */
+
+int	doread(int fd, FILE *of, const char *devname);
+void	printstatus(struct fdc_status *fdcsp);
+void	usage(void);
+
+void
+usage(void)
+{
+
+	errx(EX_USAGE,
+	     "usage: fdread [-qr] [-d device] [-f fillbyte] [-o file]");
+}
+
+
+int
+main(int argc, char **argv)
+{
+	int c, errs = 0;
+	const char *fname = 0, *devname = "/dev/fd0";
+	char *cp;
+	FILE *of = stdout;
+	int fd;
+	unsigned long ul;
+
+	while ((c = getopt(argc, argv, "d:f:o:qr")) != -1)
+		switch (c) {
+		case 'd':
+			devname = optarg;
+			break;
+
+		case 'f':
+			ul = strtoul(optarg, &cp, 0);
+			if (*cp != '\0') {
+				fprintf(stderr,
+			"Bad argument %s to -f option; must be numeric\n",
+					optarg);
+				usage();
+			}
+			if (ul > 0xff)
+				warnx(
+			"Warning: fillbyte %#lx too large, truncating\n",
+				      ul);
+			fillbyte = ul & 0xff;
+			break;
+
+		case 'o':
+			fname = optarg;
+			break;
+
+		case 'q':
+			quiet++;
+			break;
+
+		case 'r':
+			recover++;
+			break;
+
+		default:
+			errs++;
+		}
+	argc -= optind;
+	argv += optind;
+
+	if (argc != 0 || errs)
+		usage();
+
+	if (fname) {
+		if ((of = fopen(fname, "w")) == NULL)
+			err(EX_OSERR, "cannot create output file %s", fname);
+	}
+
+	if ((fd = open(devname, O_RDONLY)) == -1)
+		err(EX_OSERR, "cannot open device %s", devname);
+
+	return (doread(fd, of, devname));
+}
+
+int
+doread(int fd, FILE *of, const char *devname)
+{
+	char *trackbuf;
+	int rv, fdopts, recoverable, nerrs = 0;
+	unsigned int nbytes, tracksize, mediasize, secsize, n;
+	struct fdc_status fdcs;
+	struct fd_type fdt;
+
+	if (ioctl(fd, FD_GTYPE, &fdt) == -1)
+		err(EX_OSERR, "ioctl(FD_GTYPE) failed -- not a floppy?");
+	fdopts = FDOPT_NOERRLOG;
+	if (ioctl(fd, FD_SOPTS, &fdopts) == -1)
+		err(EX_OSERR, "ioctl(FD_SOPTS, FDOPT_NOERRLOG)");
+
+	secsize = 128 << fdt.secsize;
+	tracksize = fdt.sectrac * secsize;
+	mediasize = tracksize * fdt.tracks * fdt.heads;
+	if ((trackbuf = malloc(tracksize)) == 0)
+		errx(EX_TEMPFAIL, "out of memory");
+
+	if (!quiet)
+		fprintf(stderr, "Reading %d * %d * %d * %d medium at %s\n",
+			fdt.tracks, fdt.heads, fdt.sectrac, secsize, devname);
+
+	for (nbytes = 0; nbytes < mediasize;) {
+		if (lseek(fd, nbytes, SEEK_SET) != nbytes)
+			err(EX_OSERR, "cannot lseek()");
+		rv = read(fd, trackbuf, tracksize);
+		if (rv == 0) {
+			/* EOF? */
+			warnx("premature EOF after %u bytes", nbytes);
+			return (EX_OK);
+		}
+		if (rv == tracksize) {
+			nbytes += rv;
+			if (!quiet)
+				fprintf(stderr, "%5d KB\r", nbytes / 1024);
+			fwrite(trackbuf, sizeof(unsigned char), rv, of);
+			fflush(of);
+			continue;
+		}
+		if (rv < tracksize) {
+			/* should not happen */
+			nbytes += rv;
+			if (!quiet)
+				fprintf(stderr, "\nshort after %5d KB\r",
+					nbytes / 1024);
+			fwrite(trackbuf, sizeof(unsigned char), rv, of);
+			fflush(of);
+			continue;
+		}
+		if (rv == -1) {
+			/* fall back reading one sector at a time */
+			for (n = 0; n < tracksize; n += secsize) {
+				if (lseek(fd, nbytes, SEEK_SET) != nbytes)
+					err(EX_OSERR, "cannot lseek()");
+				rv = read(fd, trackbuf, secsize);
+				if (rv == secsize) {
+					nbytes += rv;
+					if (!quiet)
+						fprintf(stderr, "%5d KB\r",
+							nbytes / 1024);
+					fwrite(trackbuf, sizeof(unsigned char),
+					       rv, of);
+					fflush(of);
+					continue;
+				}
+				if (rv == -1) {
+					if (errno != EIO) {
+						if (!quiet)
+							putc('\n', stderr);
+						perror("non-IO error");
+						return (EX_OSERR);
+					}
+					if (ioctl(fd, FD_GSTAT, &fdcs) == -1)
+						errx(EX_IOERR,
+				     "floppy IO error, but no FDC status");
+					nerrs++;
+					recoverable = fdcs.status[2] &
+						NE7_ST2_DD;
+					if (!quiet) {
+						printstatus(&fdcs);
+						fputs(" (", stderr);
+						if (!recoverable)
+							fputs("not ", stderr);
+						fputs("recoverable)", stderr);
+					}
+					if (!recover) {
+						if (!quiet)
+							putc('\n', stderr);
+						return (EX_IOERR);
+					}
+					memset(trackbuf, fillbyte, secsize);
+					if (recoverable) {
+						fdopts |= FDOPT_NOERROR;
+						if (ioctl(fd, FD_SOPTS,
+							  &fdopts) == -1)
+							err(EX_OSERR,
+				    "ioctl(fd, FD_SOPTS, FDOPT_NOERROR)");
+						rv = read(fd, trackbuf,
+							  secsize);
+						if (rv != secsize)
+							err(EX_IOERR,
+				    "read() with FDOPT_NOERROR still fails");
+						fdopts &= ~FDOPT_NOERROR;
+						(void)ioctl(fd, FD_SOPTS,
+							    &fdopts);
+					}
+					if (!quiet) {
+						if (recoverable)
+							fprintf(stderr,
+								": recovered");
+						else
+							fprintf(stderr,
+								": dummy");
+						fprintf(stderr,
+							" data @ %#x ... %#x\n",
+							nbytes,
+							nbytes + secsize - 1);
+					}
+					nbytes += secsize;
+					fwrite(trackbuf, sizeof(unsigned char),
+					       secsize, of);
+					fflush(of);
+					continue;
+				}
+				errx(EX_OSERR, "unexpected read() result: %d",
+				     rv);
+			}
+		}
+	}
+	if (!quiet) {
+		putc('\n', stderr);
+		if (nerrs)
+			fprintf(stderr, "%d error%s\n",
+				nerrs, nerrs > 1? "s": "");
+	}
+
+	return (nerrs? EX_IOERR: EX_OK);
+}
+
+void
+printstatus(struct fdc_status *fdcsp)
+{
+	char msgbuf[100];
+
+	fprintf(stderr,
+		"\nFDC status ST0=%#x ST1=%#x ST2=%#x C=%u H=%u R=%u N=%u:\n",
+		fdcsp->status[0] & 0xff,
+		fdcsp->status[1] & 0xff,
+		fdcsp->status[2] & 0xff,
+		fdcsp->status[3] & 0xff,
+		fdcsp->status[4] & 0xff,
+		fdcsp->status[5] & 0xff,
+		fdcsp->status[6] & 0xff);
+
+	if ((fdcsp->status[0] & NE7_ST0_IC_RC) != NE7_ST0_IC_AT) {
+		sprintf(msgbuf, "unexcpted interrupt code %#x",
+			fdcsp->status[0] & NE7_ST0_IC_RC);
+	} else {
+		strcpy(msgbuf, "unexpected error code in ST1/ST2");
+
+		if (fdcsp->status[1] & NE7_ST1_EN)
+			strcpy(msgbuf, "end of cylinder (wrong format)");
+		else if (fdcsp->status[1] & NE7_ST1_DE) {
+			if (fdcsp->status[2] & NE7_ST2_DD)
+				strcpy(msgbuf, "CRC error in data field");
+			else
+				strcpy(msgbuf, "CRC error in ID field");
+		} else if (fdcsp->status[1] & NE7_ST1_MA) {
+			if (fdcsp->status[2] & NE7_ST2_MD)
+				strcpy(msgbuf, "no address mark in data field");
+			else
+				strcpy(msgbuf, "no address mark in ID field");
+		} else if (fdcsp->status[2] & NE7_ST2_WC)
+			strcpy(msgbuf, "wrong cylinder (format mismatch)");
+		else if (fdcsp->status[1] & NE7_ST1_ND)
+			strcpy(msgbuf, "no data (sector not found)");
+	}
+	fputs(msgbuf, stderr);
+}