xref: /freebsd/stand/userboot/userboot/devicename.c (revision d5b0e70f7e04d971691517ce1304d86a1e367e2e)
1 /*-
2  * Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <stand.h>
31 #include <string.h>
32 
33 #include "bootstrap.h"
34 #include "disk.h"
35 #include "libuserboot.h"
36 
37 #if defined(USERBOOT_ZFS_SUPPORT)
38 #include "libzfs.h"
39 #endif
40 
41 static int userboot_parsedev(struct disk_devdesc **dev, const char *devspec,
42     const char **path);
43 
44 /*
45  * Point (dev) at an allocated device specifier for the device matching the
46  * path in (devspec). If it contains an explicit device specification,
47  * use that.  If not, use the default device.
48  */
49 int
50 userboot_getdev(void **vdev, const char *devspec, const char **path)
51 {
52 	struct disk_devdesc **dev = (struct disk_devdesc **)vdev;
53 	int rv;
54 
55 	/*
56 	 * If it looks like this is just a path and no
57 	 * device, go with the current device.
58 	 */
59 	if ((devspec == NULL) ||
60 	    (devspec[0] == '/') ||
61 	    (strchr(devspec, ':') == NULL)) {
62 
63 		rv = userboot_parsedev(dev, getenv("currdev"), NULL);
64 		if (rv == 0 && path != NULL)
65 			*path = devspec;
66 		return (rv);
67 	}
68 
69 	/*
70 	 * Try to parse the device name off the beginning of the devspec
71 	 */
72 	return (userboot_parsedev(dev, devspec, path));
73 }
74 
75 /*
76  * Point (dev) at an allocated device specifier matching the string version
77  * at the beginning of (devspec).  Return a pointer to the remaining
78  * text in (path).
79  *
80  * In all cases, the beginning of (devspec) is compared to the names
81  * of known devices in the device switch, and then any following text
82  * is parsed according to the rules applied to the device type.
83  *
84  * For disk-type devices, the syntax is:
85  *
86  * disk<unit>[s<slice>][<partition>]:
87  *
88  */
89 static int
90 userboot_parsedev(struct disk_devdesc **dev, const char *devspec,
91     const char **path)
92 {
93 	struct disk_devdesc *idev;
94 	struct devsw *dv;
95 	int i, unit, err;
96 	const char *cp;
97 	const char *np;
98 
99 	/* minimum length check */
100 	if (strlen(devspec) < 2)
101 		return (EINVAL);
102 
103 	/* look for a device that matches */
104 	for (i = 0, dv = NULL; devsw[i] != NULL; i++) {
105 		if (strncmp(devspec, devsw[i]->dv_name,
106 		    strlen(devsw[i]->dv_name)) == 0) {
107 			dv = devsw[i];
108 			break;
109 		}
110 	}
111 	if (dv == NULL)
112 		return (ENOENT);
113 	idev = malloc(sizeof(struct disk_devdesc));
114 	err = 0;
115 	np = (devspec + strlen(dv->dv_name));
116 
117 	switch (dv->dv_type) {
118 	case DEVT_NONE:			/* XXX what to do here?  Do we care? */
119 		break;
120 
121 	case DEVT_DISK:
122 		err = disk_parsedev(idev, np, path);
123 		if (err != 0)
124 			goto fail;
125 		break;
126 
127 	case DEVT_CD:
128 	case DEVT_NET:
129 		unit = 0;
130 
131 		if (*np && (*np != ':')) {
132 			/* get unit number if present */
133 			unit = strtol(np, (char **)&cp, 0);
134 			if (cp == np) {
135 				err = EUNIT;
136 				goto fail;
137 			}
138 		} else {
139 			cp = np;
140 		}
141 		if (*cp && (*cp != ':')) {
142 			err = EINVAL;
143 			goto fail;
144 		}
145 
146 		idev->dd.d_unit = unit;
147 		if (path != NULL)
148 			*path = (*cp == 0) ? cp : cp + 1;
149 		break;
150 
151 	case DEVT_ZFS:
152 #if defined(USERBOOT_ZFS_SUPPORT)
153 		err = zfs_parsedev((struct zfs_devdesc *)idev, np, path);
154 		if (err != 0)
155 			goto fail;
156 		break;
157 #else
158 		/* FALLTHROUGH */
159 #endif
160 
161 	default:
162 		err = EINVAL;
163 		goto fail;
164 	}
165 	idev->dd.d_dev = dv;
166 	if (dev == NULL) {
167 		free(idev);
168 	} else {
169 		*dev = idev;
170 	}
171 	return (0);
172 
173 fail:
174 	free(idev);
175 	return (err);
176 }
177 
178 
179 /*
180  * Set currdev to suit the value being supplied in (value)
181  */
182 int
183 userboot_setcurrdev(struct env_var *ev, int flags, const void *value)
184 {
185 	struct disk_devdesc *ncurr;
186 	int rv;
187 
188 	if ((rv = userboot_parsedev(&ncurr, value, NULL)) != 0)
189 		return (rv);
190 	free(ncurr);
191 
192 	return (mount_currdev(ev, flags, value));
193 }
194