devicename.c

/*
 * Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
 * 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 AUTHOR AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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/cdefs.h>

#include <stand.h>
#include <string.h>
#include <sys/param.h>
#include "bootstrap.h"
#include "disk.h"
#include "libi386.h"
#include "libzfs.h"

static int i386_parsedev(struct i386_devdesc **, const char *, const char **);

/*
 * Point dev at an allocated device specifier for the device matching the
 * path in devspec. If it contains an explicit device specification,
 * use that.  If not, use the default device.
 */
int
i386_getdev(void **vdev, const char *devspec, const char **path)
{
	struct i386_devdesc **dev = (struct i386_devdesc **)vdev;
	int rv;

	/*
	 * If it looks like this is just a path and no
	 * device, go with the current device.
	 */
	if ((devspec == NULL) ||
	    (devspec[0] == '/') || (strchr(devspec, ':') == NULL)) {

		rv = i386_parsedev(dev, getenv("currdev"), NULL);
		if (rv == 0 && path != NULL)
			*path = devspec;
		return (rv);
	}

	/*
	 * Try to parse the device name off the beginning of the devspec
	 */
	return (i386_parsedev(dev, devspec, path));
}

/*
 * Point (dev) at an allocated device specifier matching the string version
 * at the beginning of (devspec).  Return a pointer to the remaining
 * text in (path).
 *
 * In all cases, the beginning of (devspec) is compared to the names
 * of known devices in the device switch, and then any following text
 * is parsed according to the rules applied to the device type.
 *
 * For disk-type devices, the syntax is:
 *
 * disk<unit>[s<slice>][<partition>]:
 *
 */
static int
i386_parsedev(struct i386_devdesc **dev, const char *devspec, const char **path)
{
	struct i386_devdesc *idev;
	struct devsw *dv;
	int i, unit, err;
	char *cp;
	const char *np;

	/* minimum length check */
	if (strlen(devspec) < 2)
		return (EINVAL);

	/* look for a device that matches */
	for (i = 0, dv = NULL; devsw[i] != NULL; i++) {
		dv = devsw[i];
		if (strncmp(devspec, dv->dv_name, strlen(dv->dv_name)) == 0)
			break;
	}
	if (devsw[i] == NULL)
		return (ENOENT);

	np = devspec + strlen(dv->dv_name);
	idev = NULL;
	err = 0;

	switch (dv->dv_type) {
	case DEVT_NONE:
		break;

	case DEVT_DISK:
		idev = malloc(sizeof (struct i386_devdesc));
		if (idev == NULL)
			return (ENOMEM);

		err = disk_parsedev((struct disk_devdesc *)idev, np, path);
		if (err != 0)
			goto fail;
		break;

	case DEVT_ZFS:
		idev = malloc(sizeof (struct zfs_devdesc));
		if (idev == NULL)
			return (ENOMEM);

		err = zfs_parsedev((struct zfs_devdesc *)idev, np, path);
		if (err != 0)
			goto fail;
		break;

	default:
		idev = malloc(sizeof (struct devdesc));
		if (idev == NULL)
			return (ENOMEM);

		unit = 0;
		cp = (char *)np;

		if (*np && (*np != ':')) {
			/* get unit number if present */
			unit = strtol(np, &cp, 0);
			if (cp == np) {
				err = EUNIT;
				goto fail;
			}
		}
		if (*cp && (*cp != ':')) {
			err = EINVAL;
			goto fail;
		}

		idev->dd.d_unit = unit;
		if (path != NULL)
			*path = (*cp == '\0') ? cp : cp + 1;
		break;
	}

	idev->dd.d_dev = dv;

	if (dev != NULL)
		*dev = idev;
	else
		free(idev);
	return (0);

fail:
	free(idev);
	return (err);
}


char *
i386_fmtdev(void *vdev)
{
	struct i386_devdesc *dev = (struct i386_devdesc *)vdev;
	static char buf[SPECNAMELEN + 1];

	switch (dev->dd.d_dev->dv_type) {
	case DEVT_NONE:
		strlcpy(buf, "(no device)", sizeof (buf));
		break;

	case DEVT_DISK:
		return (disk_fmtdev(vdev));

	case DEVT_ZFS:
		return (zfs_fmtdev(vdev));

	default:
		snprintf(buf, sizeof (buf), "%s%d:", dev->dd.d_dev->dv_name,
		    dev->dd.d_unit);
		break;
	}
	return (buf);
}


/*
 * Set currdev to suit the value being supplied in (value)
 */
int
i386_setcurrdev(struct env_var *ev, int flags, const void *value)
{
	struct i386_devdesc *ncurr;
	int rv;

	if ((rv = i386_parsedev(&ncurr, value, NULL)) != 0)
		return (rv);

	free(ncurr);
	env_setenv(ev->ev_name, flags | EV_NOHOOK, value, NULL, NULL);
	return (0);
}