xref: /openbsd-src/sbin/fdisk/disk.c (revision a28daedfc357b214be5c701aa8ba8adb29a7f1c2)
1 /*	$OpenBSD: disk.c,v 1.29 2009/02/08 18:03:18 krw Exp $	*/
2 
3 /*
4  * Copyright (c) 1997, 2001 Tobias Weingartner
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  */
27 
28 #include <err.h>
29 #include <util.h>
30 #include <stdio.h>
31 #include <stdlib.h>
32 #include <unistd.h>
33 #include <sys/fcntl.h>
34 #include <sys/ioctl.h>
35 #include <sys/types.h>
36 #include <sys/stat.h>
37 #include <sys/disklabel.h>
38 #include <sys/param.h>
39 #include "disk.h"
40 #include "misc.h"
41 
42 DISK_metrics *DISK_getlabelmetrics(char *name);
43 
44 int
45 DISK_open(char *disk, int mode)
46 {
47 	int fd;
48 	struct stat st;
49 
50 	fd = opendev(disk, mode, OPENDEV_PART, NULL);
51 	if (fd == -1)
52 		err(1, "%s", disk);
53 	if (fstat(fd, &st) == -1)
54 		err(1, "%s", disk);
55 	if (!S_ISCHR(st.st_mode) && !S_ISREG(st.st_mode))
56 		err(1, "%s is not a character device or a regular file", disk);
57 	return (fd);
58 }
59 
60 /* Routine to go after the disklabel for geometry
61  * information.  This should work everywhere, but
62  * in the land of PC, things are not always what
63  * they seem.
64  */
65 DISK_metrics *
66 DISK_getlabelmetrics(char *name)
67 {
68 	DISK_metrics *lm = NULL;
69 	struct disklabel dl;
70 	int fd;
71 
72 	/* Get label metrics */
73 	if ((fd = DISK_open(name, O_RDONLY)) != -1) {
74 		lm = malloc(sizeof(DISK_metrics));
75 		if (lm == NULL)
76 			err(1, NULL);
77 
78 		if (ioctl(fd, DIOCGPDINFO, &dl) == -1 &&
79 		    ioctl(fd, DIOCGDINFO, &dl) == -1) {
80 			warn("DIOCGDINFO");
81 			free(lm);
82 			lm = NULL;
83 		} else {
84 			lm->cylinders = dl.d_ncylinders;
85 			lm->heads = dl.d_ntracks;
86 			lm->sectors = dl.d_nsectors;
87 			lm->size = dl.d_secperunit;
88 			unit_types[SECTORS].conversion = dl.d_secsize;
89 		}
90 		close(fd);
91 	}
92 
93 	return (lm);
94 }
95 
96 /* This is ugly, and convoluted.  All the magic
97  * for disk geo/size happens here.  Basically,
98  * the real size is the one we will use in the
99  * rest of the program, the label size is what we
100  * got from the disklabel.  If the disklabel fails,
101  * we assume we are working with a normal file,
102  * and should request the user to specify the
103  * geometry he/she wishes to use.
104  */
105 int
106 DISK_getmetrics(disk_t *disk, DISK_metrics *user)
107 {
108 
109 	disk->label = DISK_getlabelmetrics(disk->name);
110 
111 	/* If user supplied, use that */
112 	if (user) {
113 		disk->real = user;
114 		return (0);
115 	}
116 
117 	/* If we have a label, use that */
118 	if (disk->label) {
119 		disk->real = disk->label;
120 		return (0);
121 	}
122 
123 	/* Can not get geometry, punt */
124 	disk->real = NULL;
125 	return (1);
126 }
127 
128 /*
129  * Print the disk geometry information. Take an optional modifier
130  * to indicate the units that should be used for display.
131  */
132 int
133 DISK_printmetrics(disk_t *disk, char *units)
134 {
135 	const int secsize = unit_types[SECTORS].conversion;
136 	double size;
137 	int i;
138 
139 	i = unit_lookup(units);
140 	size = ((double)disk->real->size * secsize) / unit_types[i].conversion;
141 	printf("Disk: %s\t", disk->name);
142 	if (disk->real) {
143 		printf("geometry: %d/%d/%d [%.0f ",
144 		    disk->real->cylinders, disk->real->heads,
145 		    disk->real->sectors, size);
146 		if (i == SECTORS && secsize != DEV_BSIZE)
147 			printf("%d-byte ", secsize);
148 		printf("%s]\n", unit_types[i].lname);
149 	} else
150 		printf("geometry: <none>\n");
151 
152 	return (0);
153 }
154 
155