Import Jason Thorpe's contribution for an updated SCSI media changer

device (now, finally!).

5 files changed, 966 insertions, 0 deletions

diff --git a/bin/chio/Makefile b/bin/chio/Makefile
new file mode 100644
index 0000000..73c1aa1
--- /dev/null
+++ b/bin/chio/Makefile
@@ -0,0 +1,9 @@
+#	$Id: $
+#	@(#)Makefile	8.1 (Berkeley) 6/6/93
+
+PROG=	chio
+SRCS=	chio.c
+BINOWN=	root
+BINMODE=4555
+
+.include <bsd.prog.mk>
diff --git a/bin/chio/chio.1 b/bin/chio/chio.1
new file mode 100644
index 0000000..22696f4
--- /dev/null
+++ b/bin/chio/chio.1
@@ -0,0 +1,202 @@
+.\"	$NetBSD: $
+.\"
+.\" Copyright (c) 1996 Jason R. Thorpe <thorpej@and.com>
+.\" 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.
+.\" 3. All advertising materials mentioning features or use of this software
+.\"    must display the following acknowledgements:
+.\"	This product includes software developed by Jason R. Thorpe
+.\"	for And Communications, http://www.and.com/
+.\" 4. The name of the author may not be used to endorse or promote products
+.\"    derived from this software without specific prior written permission.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
+.\"
+.Dd April 2, 1996
+.Dt CHIO 1
+.Os
+.Sh NAME
+.Nm chio
+.Nd medium changer control utility
+.Sh SYNOPSIS
+.Nm chio
+.Op Fl f Ar changer
+.Ar command
+.Ar arg1
+.Ar arg2
+.Oo
+.Ar arg3 Oo ...
+.Oc
+.Oc
+.Sh DESCRIPTION
+.Nm Chio
+is used to control the operation of medium changers, such as those found
+in tape and optical disk jukeboxes.
+.Pp
+The options are as follows:
+.Bl -tag -width indent
+.It Fl f Ar changer
+Use the device
+.Pa changer
+rather than the default device
+.Pa /dev/ch0 .
+.El
+.Pp
+The default changer may be overridden by setting the environment variable
+.Nm CHANGER
+to the desired changer device.
+.Pp
+A medium changer apparatus is made up of
+.Pa elements .
+There are four element types:
+.Pa picker
+(medium transport),
+.Pa slot
+(storage),
+.Pa portal
+(import/export), and
+.Pa drive
+(data transfer).  In this command description, the shorthand
+.Nm ET
+will be used to represent an element type, and
+.Nm EU
+will be used to represent an element unit.  For example, to represent
+the first robotic arm in the changer, the ET would be
+.Dq picker
+and the EU would be
+.Dq 0 .
+.Pp
+.Sh SUPPORTED COMMANDS
+.Nm chio move
+.Ar <from ET> <from EU> <to ET> <to EU>
+.Op Ar inv
+.Pp
+Moves the media unit from
+.Pa <from ET/EU>
+to
+.Pa <to ET/EU> .
+If the optional modifier
+.Pa inv
+is specified, the media unit will be inverted before insertion.
+.Pp
+.Nm chio exchange
+.Ar <src ET> <src EU> <dst1 ET> <dst1 EU>
+.Op Ar <dst2 ET> <dst2 ET>
+.Op Ar inv1
+.Op Ar inv2
+.Pp
+Performs a media unit exchange operation.  The media unit in
+.Pa <src ET/EU>
+is moved to
+.Pa <dst1 ET/EU>
+and the media unit previously in
+.Pa <dst1 ET/EU>
+is moved to
+.Pa <dst2 ET/EU> .
+In the case of a simple exchange,
+.Pa <dst2 ET/EU>
+is omitted and the values
+.Pa <src ET/EU>
+are used in their place.
+The optional modifiers
+.Pa inv1
+and
+.Pa inv2
+specify whether the media units are to be inverted before insertion into
+.Pa <dst1 ET/EU>
+and
+.Pa <dst2 ET/EU>
+respecitively.
+.Pp
+Note that not all medium changers support the
+.Nm exchange
+operation; The changer must have multiple free pickers or emulate
+multiple free pickers with transient storage.
+.Pp
+.Nm chio position
+.Ar <to ET> <to EU>
+.Op Ar inv
+.Pp
+Position the picker in front of the element described by
+.Pa <to ET/EU> .
+If the optional modifier
+.Pa inv
+is specified, the media unit will be inverted before insertion.
+.Pp
+Note that not all changers behave as expected when issued this command.
+.Pp
+.Nm chio params
+.Pp
+Report the number of slots, drives, pickers, and portals in the changer,
+and which picker unit the changer is currently configured to use.
+.Pp
+.Nm chio getpicker
+.Pp
+Report which picker unit the changer is currently configured to use.
+.Pp
+.Nm chio setpicker
+.Ar <unit>
+.Pp
+Configure the changer to use picker
+.Pa <unit> .
+.Pp
+.Nm chio status
+.Op Ar <type>
+.Pp
+Report the status of all elements in the changer.  If
+.Pa <type>
+is specified, report the status of all elements of type
+.Pa <type> .
+.Pp
+The status bits are defined as follows:
+.Bl -tag -width indent
+.It Nm FULL
+Element contains a media unit.
+.It Nm IMPEXP
+Media was deposited into element by an outside human operator.
+.It Nm EXCEPT
+Element is in an abnormal state.
+.It Nm ACCESS
+Media in this element is accessible by a picker.
+.It Nm EXENAB
+Element supports passing media (exporting) to an outsite human operator.
+.It Nm INENAB
+Element supports receiving media (importing) from an outside human operator.
+.El
+.Pp
+.Sh EXAMPLES
+.Nm chio move slot 3 drive 0
+.Pp
+Moves the media in slot 3 (fourth slot) to drive 0 (first drive).
+.Pp
+.Nm chio setpicker 2
+Configures the changer to use picker 2 (third picker) for operations.
+.Pp
+.Sh FILES
+/dev/ch0 - default changer device
+.Sh SEE ALSO
+.Xr mt 1 ,
+.Xr mount 8 .
+.Sh AUTHOR
+The
+.Nm chio
+program and SCSI changer driver were written by Jason R. Thorpe
+<thorpej@and.com> for And Communications, http://www.and.com/
diff --git a/bin/chio/chio.c b/bin/chio/chio.c
new file mode 100644
index 0000000..51a84e9
--- /dev/null
+++ b/bin/chio/chio.c
@@ -0,0 +1,663 @@
+/*	$Id: $	*/
+
+/*
+ * Copyright (c) 1996 Jason R. Thorpe <thorpej@and.com>
+ * 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.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgements:
+ *	This product includes software developed by Jason R. Thorpe
+ *	for And Communications, http://www.and.com/
+ * 4. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
+ */
+
+#include <sys/param.h>
+#include <sys/ioctl.h>
+#include <sys/chio.h> 
+#include <err.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "defs.h"
+#include "pathnames.h"
+
+extern	char *__progname;	/* from crt0.o */
+
+static	void usage __P((void));
+static	void cleanup __P((void));
+static	int parse_element_type __P((char *));
+static	int parse_element_unit __P((char *));
+static	int parse_special __P((char *));
+static	int is_special __P((char *));
+static	char *bits_to_string __P((int, const char *));
+
+static	int do_move __P((char *, int, char **));
+static	int do_exchange __P((char *, int, char **));
+static	int do_position __P((char *, int, char **));
+static	int do_params __P((char *, int, char **));
+static	int do_getpicker __P((char *, int, char **));
+static	int do_setpicker __P((char *, int, char **));
+static	int do_status __P((char *, int, char **));
+
+/* Valid changer element types. */
+const struct element_type elements[] = {
+	{ "picker",		CHET_MT },
+	{ "slot",		CHET_ST },
+	{ "portal",		CHET_IE },
+	{ "drive",		CHET_DT },
+	{ NULL,			0 },
+};
+
+/* Valid commands. */
+const struct changer_command commands[] = {
+	{ "move",		do_move },
+	{ "exchange",		do_exchange },
+	{ "position",		do_position },
+	{ "params",		do_params },
+	{ "getpicker",		do_getpicker },
+	{ "setpicker",		do_setpicker },
+	{ "status",		do_status },
+	{ NULL,			0 },
+};
+
+/* Valid special words. */
+const struct special_word specials[] = {
+	{ "inv",		SW_INVERT },
+	{ "inv1",		SW_INVERT1 },
+	{ "inv2",		SW_INVERT2 },
+	{ NULL,			0 },
+};
+
+static	int changer_fd;
+static	char *changer_name;
+
+int
+main(argc, argv)
+	int argc;
+	char **argv;
+{
+	int ch, i;
+	char *cp;
+
+	while ((ch = getopt(argc, argv, "f:")) != -1) {
+		switch (ch) {
+		case 'f':
+			changer_name = optarg;
+			break;
+
+		default:
+			usage();
+		}
+	}
+	argc -= optind;
+	argv += optind;
+
+	if (argc == 0)
+		usage();
+
+	/* Get the default changer if not already specified. */
+	if (changer_name == NULL)
+		if ((changer_name = getenv(CHANGER_ENV_VAR)) == NULL)
+			changer_name = _PATH_CH;
+
+	/* Open the changer device. */
+	if ((changer_fd = open(changer_name, O_RDWR, 0600)) == -1)
+		err(1, "%s: open", changer_name);
+
+	/* Register cleanup function. */
+	if (atexit(cleanup))
+		err(1, "can't register cleanup function");
+
+	/* Find the specified command. */
+	for (i = 0; commands[i].cc_name != NULL; ++i)
+		if (strcmp(*argv, commands[i].cc_name) == 0)
+			break;
+	if (commands[i].cc_name == NULL)
+		errx(1, "unknown command: %s", *argv);
+
+	/* Skip over the command name and call handler. */
+	++argv; --argc;
+	exit ((*commands[i].cc_handler)(commands[i].cc_name, argc, argv));
+}
+
+static int
+do_move(cname, argc, argv)
+	char *cname;
+	int argc;
+	char **argv;
+{
+	struct changer_move cmd;
+	int val;
+
+	/*
+	 * On a move command, we expect the following:
+	 *
+	 * <from ET> <from EU> <to ET> <to EU> [inv]
+	 *
+	 * where ET == element type and EU == element unit.
+	 */
+	if (argc < 4) {
+		warnx("%s: too few arguments", cname);
+		goto usage;
+	} else if (argc > 5) {
+		warnx("%s: too many arguments", cname);
+		goto usage;
+	}
+	bzero(&cmd, sizeof(cmd));
+
+	/* <from ET>  */
+	cmd.cm_fromtype = parse_element_type(*argv);
+	++argv; --argc;
+
+	/* <from EU> */
+	cmd.cm_fromunit = parse_element_unit(*argv);
+	++argv; --argc;
+
+	/* <to ET> */
+	cmd.cm_totype = parse_element_type(*argv);
+	++argv; --argc;
+
+	/* <to EU> */
+	cmd.cm_tounit = parse_element_unit(*argv);
+	++argv; --argc;
+
+	/* Deal with optional command modifier. */
+	if (argc) {
+		val = parse_special(*argv);
+		switch (val) {
+		case SW_INVERT:
+			cmd.cm_flags |= CM_INVERT;
+			break;
+
+		default:
+			errx(1, "%s: inappropriate modifier `%s'",
+			    cname, *argv);
+			/* NOTREACHED */
+		}
+	}
+
+	/* Send command to changer. */
+	if (ioctl(changer_fd, CHIOMOVE, (char *)&cmd))
+		err(1, "%s: CHIOMOVE", changer_name);
+
+	return (0);
+
+ usage:
+	fprintf(stderr, "usage: %s %s "
+	    "<from ET> <from EU> <to ET> <to EU> [inv]\n", __progname, cname);
+	return (1);
+}
+
+static int
+do_exchange(cname, argc, argv)
+	char *cname;
+	int argc;
+	char **argv;
+{
+	struct changer_exchange cmd;
+	int val;
+
+	/*
+	 * On an exchange command, we expect the following:
+	 *
+  * <src ET> <src EU> <dst1 ET> <dst1 EU> [<dst2 ET> <dst2 EU>] [inv1] [inv2]
+	 *
+	 * where ET == element type and EU == element unit.
+	 */
+	if (argc < 4) {
+		warnx("%s: too few arguments", cname);
+		goto usage;
+	} else if (argc > 8) {
+		warnx("%s: too many arguments", cname);
+		goto usage;
+	}
+	bzero(&cmd, sizeof(cmd));
+
+	/* <src ET>  */
+	cmd.ce_srctype = parse_element_type(*argv);
+	++argv; --argc;
+
+	/* <src EU> */
+	cmd.ce_srcunit = parse_element_unit(*argv);
+	++argv; --argc;
+
+	/* <dst1 ET> */
+	cmd.ce_fdsttype = parse_element_type(*argv);
+	++argv; --argc;
+
+	/* <dst1 EU> */
+	cmd.ce_fdstunit = parse_element_unit(*argv);
+	++argv; --argc;
+
+	/*
+	 * If the next token is a special word or there are no more
+	 * arguments, then this is a case of simple exchange.
+	 * dst2 == src.
+	 */
+	if ((argc == 0) || is_special(*argv)) {
+		cmd.ce_sdsttype = cmd.ce_srctype;
+		cmd.ce_sdstunit = cmd.ce_srcunit;
+		goto do_special;
+	}
+
+	/* <dst2 ET> */
+	cmd.ce_sdsttype = parse_element_type(*argv);
+	++argv; --argc;
+
+	/* <dst2 EU> */
+	cmd.ce_sdstunit = parse_element_unit(*argv);
+	++argv; --argc;
+
+ do_special:
+	/* Deal with optional command modifiers. */
+	while (argc) {
+		val = parse_special(*argv);
+		++argv; --argc;
+		switch (val) {
+		case SW_INVERT1:
+			cmd.ce_flags |= CE_INVERT1;
+			break;
+
+		case SW_INVERT2:
+			cmd.ce_flags |= CE_INVERT2;
+			break;
+
+		default:
+			errx(1, "%s: inappropriate modifier `%s'",
+			    cname, *argv);
+			/* NOTREACHED */
+		}
+	}
+
+	/* Send command to changer. */
+	if (ioctl(changer_fd, CHIOEXCHANGE, (char *)&cmd))
+		err(1, "%s: CHIOEXCHANGE", changer_name);
+
+	return (0);
+
+ usage:
+	fprintf(stderr, "usage: %s %s <src ET> <src EU> <dst1 ET> <dst1 EU>\n"
+	    "       [<dst2 ET> <dst2 EU>] [inv1] [inv2]\n",
+	    __progname, cname);
+	return (1);
+}
+
+static int
+do_position(cname, argc, argv)
+	char *cname;
+	int argc;
+	char **argv;
+{
+	struct changer_position cmd;
+	int val;
+
+	/*
+	 * On a position command, we expect the following:
+	 *
+	 * <to ET> <to EU> [inv]
+	 *
+	 * where ET == element type and EU == element unit.
+	 */
+	if (argc < 2) {
+		warnx("%s: too few arguments", cname);
+		goto usage;
+	} else if (argc > 3) {
+		warnx("%s: too many arguments", cname);
+		goto usage;
+	}
+	bzero(&cmd, sizeof(cmd));
+
+	/* <to ET>  */
+	cmd.cp_type = parse_element_type(*argv);
+	++argv; --argc;
+
+	/* <to EU> */
+	cmd.cp_unit = parse_element_unit(*argv);
+	++argv; --argc;
+
+	/* Deal with optional command modifier. */
+	if (argc) {
+		val = parse_special(*argv);
+		switch (val) {
+		case SW_INVERT:
+			cmd.cp_flags |= CP_INVERT;
+			break;
+
+		default:
+			errx(1, "%s: inappropriate modifier `%s'",
+			    cname, *argv);
+			/* NOTREACHED */
+		}
+	}
+
+	/* Send command to changer. */
+	if (ioctl(changer_fd, CHIOPOSITION, (char *)&cmd))
+		err(1, "%s: CHIOPOSITION", changer_name);
+
+	return (0);
+
+ usage:
+	fprintf(stderr, "usage: %s %s <to ET> <to EU> [inv]\n",
+	    __progname, cname);
+	return (1);
+}
+
+static int
+do_params(cname, argc, argv)
+	char *cname;
+	int argc;
+	char **argv;
+{
+	struct changer_params data;
+
+	/* No arguments to this command. */
+	if (argc) {
+		warnx("%s: no arguements expected", cname);
+		goto usage;
+	}
+
+	/* Get params from changer and display them. */
+	bzero(&data, sizeof(data));
+	if (ioctl(changer_fd, CHIOGPARAMS, (char *)&data))
+		err(1, "%s: CHIOGPARAMS", changer_name);
+
+	printf("%s: %d slot%s, %d drive%s, %d picker%s",
+	    changer_name,
+	    data.cp_nslots, (data.cp_nslots > 1) ? "s" : "",
+	    data.cp_ndrives, (data.cp_ndrives > 1) ? "s" : "",
+	    data.cp_npickers, (data.cp_npickers > 1) ? "s" : "");
+	if (data.cp_nportals)
+		printf(", %d portal%s", data.cp_nportals,
+		    (data.cp_nportals > 1) ? "s" : "");
+	printf("\n%s: current picker: %d\n", changer_name, data.cp_curpicker);
+
+	return (0);
+
+ usage:
+	fprintf(stderr, "usage: %s %s\n", __progname, cname);
+	return (1);
+}
+
+static int
+do_getpicker(cname, argc, argv)
+	char *cname;
+	int argc;
+	char **argv;
+{
+	int picker;
+
+	/* No arguments to this command. */
+	if (argc) {
+		warnx("%s: no arguments expected", cname);
+		goto usage;
+	}
+
+	/* Get current picker from changer and display it. */
+	if (ioctl(changer_fd, CHIOGPICKER, (char *)&picker))
+		err(1, "%s: CHIOGPICKER", changer_name);
+
+	printf("%s: current picker: %d\n", changer_name, picker);
+
+	return (0);
+
+ usage:
+	fprintf(stderr, "usage: %s %s\n", __progname, cname);
+	return (1);
+}
+
+static int
+do_setpicker(cname, argc, argv)
+	char *cname;
+	int argc;
+	char **argv;
+{
+	int picker;
+
+	if (argc < 1) {
+		warnx("%s: too few arguments", cname);
+		goto usage;
+	} else if (argc > 1) {
+		warnx("%s: too many arguments", cname);
+		goto usage;
+	}
+
+	picker = parse_element_unit(*argv);
+
+	/* Set the changer picker. */
+	if (ioctl(changer_fd, CHIOSPICKER, (char *)&picker))
+		err(1, "%s: CHIOSPICKER", changer_name);
+
+	return (0);
+
+ usage:
+	fprintf(stderr, "usage: %s %s <picker>\n", __progname, cname);
+	return (1);
+}
+
+static int
+do_status(cname, argc, argv)
+	char *cname;
+	int argc;
+	char **argv;
+{
+	struct changer_element_status cmd;
+	struct changer_params data;
+	u_int8_t *statusp;
+	int i, count, chet, schet, echet;
+	char *cmdname, *description;
+
+	/*
+	 * On a status command, we expect the following:
+	 *
+	 * [<ET>]
+	 *
+	 * where ET == element type.
+	 *
+	 * If we get no arguments, we get the status of all
+	 * known element types.
+	 */
+	if (argc > 1) {
+		warnx("%s: too many arguments", cname);
+		goto usage;
+	}
+
+	/*
+	 * Get params from changer.  Specifically, we need the element
+	 * counts.
+	 */
+	bzero(&data, sizeof(data));
+	if (ioctl(changer_fd, CHIOGPARAMS, (char *)&data))
+		err(1, "%s: CHIOGPARAMS", changer_name);
+
+	if (argc)
+		schet = echet = parse_element_type(*argv);
+	else {
+		schet = CHET_MT;
+		echet = CHET_DT;
+	}
+
+	for (chet = schet; chet <= echet; ++chet) {
+		switch (chet) {
+		case CHET_MT:
+			count = data.cp_npickers;
+			description = "picker";
+			break;
+
+		case CHET_ST:
+			count = data.cp_nslots;
+			description = "slot";
+			break;
+
+		case CHET_IE:
+			count = data.cp_nportals;
+			description = "portal";
+			break;
+
+		case CHET_DT:
+			count = data.cp_ndrives;
+			description = "drive";
+			break;
+		}
+
+		if (count == 0) {
+			if (argc == 0)
+				continue;
+			else {
+				printf("%s: no %s elements\n",
+				    changer_name, description);
+				return (0);
+			}
+		}
+
+		/* Allocate storage for the status bytes. */
+		if ((statusp = (u_int8_t *)malloc(count)) == NULL)
+			errx(1, "can't allocate status storage");
+
+		bzero(statusp, count);
+		bzero(&cmd, sizeof(cmd));
+
+		cmd.ces_type = chet;
+		cmd.ces_data = statusp;
+
+		if (ioctl(changer_fd, CHIOGSTATUS, (char *)&cmd)) {
+			free(statusp);
+			err(1, "%s: CHIOGSTATUS", changer_name);
+		}
+
+		/* Dump the status for each element of this type. */
+		for (i = 0; i < count; ++i) {
+			printf("%s %d: %s\n", description, i,
+			    bits_to_string(statusp[i], CESTATUS_BITS));
+		}
+
+		free(statusp);
+	}
+
+	return (0);
+
+ usage:
+	fprintf(stderr, "usage: %s %s [<element type>]\n", __progname,
+	    cname);
+	return (1);
+}
+
+static int
+parse_element_type(cp)
+	char *cp;
+{
+	int i;
+
+	for (i = 0; elements[i].et_name != NULL; ++i)
+		if (strcmp(elements[i].et_name, cp) == 0)
+			return (elements[i].et_type);
+
+	errx(1, "invalid element type `%s'", cp);
+}
+
+static int
+parse_element_unit(cp)
+	char *cp;
+{
+	int i;
+	char *p;
+
+	i = (int)strtol(cp, &p, 10);
+	if ((i < 0) || (*p != '\0'))
+		errx(1, "invalid unit number `%s'", cp);
+
+	return (i);
+}
+
+static int
+parse_special(cp)
+	char *cp;
+{
+	int val;
+
+	val = is_special(cp);
+	if (val)
+		return (val);
+
+	errx(1, "invalid modifier `%s'", cp);
+}
+
+static int
+is_special(cp)
+	char *cp;
+{
+	int i;
+
+	for (i = 0; specials[i].sw_name != NULL; ++i)
+		if (strcmp(specials[i].sw_name, cp) == 0)
+			return (specials[i].sw_value);
+
+	return (0);
+}
+
+static char *
+bits_to_string(v, cp)
+	int v;
+	const char *cp;
+{
+	const char *np;
+	char f, sep, *bp;
+	static char buf[128];
+
+	bp = buf;
+	bzero(buf, sizeof(buf));
+
+	for (sep = '<'; (f = *cp++) != 0; cp = np) {
+		for (np = cp; *np >= ' ';)
+			np++;
+		if ((v & (1 << (f - 1))) == 0)
+			continue;
+		bp += sprintf(bp, "%c%.*s", sep, np - cp, cp);
+		sep = ',';
+	}
+	if (sep != '<')
+		*bp = '>';
+
+	return (buf);
+}
+
+static void
+cleanup()
+{
+
+	/* Simple enough... */
+	(void)close(changer_fd);
+}
+
+static void
+usage()
+{
+
+	fprintf(stderr, "usage: %s command arg1 arg2 ...\n", __progname);
+	exit(1);
+}
diff --git a/bin/chio/defs.h b/bin/chio/defs.h
new file mode 100644
index 0000000..5bab57e
--- /dev/null
+++ b/bin/chio/defs.h
@@ -0,0 +1,57 @@
+/*	$Id: $	*/
+
+/*
+ * Copyright (c) 1996 Jason R. Thorpe <thorpej@and.com>
+ * 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.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgements:
+ *	This product includes software developed by Jason R. Thorpe
+ *	for And Communications, http://www.and.com/
+ * 4. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
+ */
+
+struct element_type {
+	char	*et_name;	/* name; i.e. "picker, "slot", etc. */
+	int	et_type;	/* type number */
+};
+
+struct changer_command {
+	char	*cc_name;	/* command name */
+				/* command handler */
+	int	(*cc_handler) __P((char *, int, char **));
+};
+
+struct special_word {
+	char	*sw_name;	/* special word */
+	int	sw_value;	/* token value */
+};
+
+/* sw_value */
+#define SW_INVERT	1	/* set "invert media" flag */
+#define SW_INVERT1	2	/* set "invert media 1" flag */
+#define SW_INVERT2	3	/* set "invert media 2" flag */
+
+/* Environment variable to check for default changer. */
+#define CHANGER_ENV_VAR		"CHANGER"
diff --git a/bin/chio/pathnames.h b/bin/chio/pathnames.h
new file mode 100644
index 0000000..cdd67fa
--- /dev/null
+++ b/bin/chio/pathnames.h
@@ -0,0 +1,35 @@
+/*	$Id: $	*/
+
+/*
+ * Copyright (c) 1996 Jason R. Thorpe <thorpej@and.com>
+ * 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.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgements:
+ *	This product includes software developed by Jason R. Thorpe
+ *	for And Communications, http://www.and.com/
+ * 4. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
+ */
+
+#define _PATH_CH	"/dev/ch0"