1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
|
/*
rdev.c - query/set root device.
-------------------------------------------------------------------------
Date: Sun, 27 Dec 1992 15:55:31 +0000
Subject: Re: rdev
From: almesber@nessie.cs.id.ethz.ch (Werner Almesberger)
To: Rik Faith <faith@cs.unc.edu>
There are quite a few versions of rdev:
- the original rootdev that only printed the current root device, by
Linus.
- rdev that does what rootdev did and that also allows you to change
the root (and swap) device, by me.
- rdev got renamed to setroot and I think even to rootdev on various
distributions.
- Peter MacDonald added video mode and RAM disk setting and included
this version on SLS, called rdev again. I've attached his rdev.c to
this mail.
-------------------------------------------------------------------------
Date: 11 Mar 92 21:37:37 GMT
Subject: rdev - query/set root device
From: almesber@nessie.cs.id.ethz.ch (Werner Almesberger)
Organization: Swiss Federal Institute of Technology (ETH), Zurich, CH
With all that socket, X11, disk driver and FS hacking going on, apparently
nobody has found time to address one of the minor nuisances of life: set-
ting the root FS device is still somewhat cumbersome. I've written a little
utility which can read and set the root device in boot images:
rdev accepts an optional offset argument, just in case the address should
ever move from 508. If called without arguments, rdev outputs an mtab line
for the current root FS, just like /etc/rootdev does.
ramsize sets the size of the ramdisk. If size is zero, no ramdisk is used.
vidmode sets the default video mode at bootup time. -1 uses default video
mode, -2 uses menu.
-------------------------------------------------------------------------
Sun Dec 27 10:42:16 1992: Minor usage changes, faith@cs.unc.edu.
Tue Mar 30 09:31:52 1993: rdev -Rn to set root readonly flag, sct@dcs.ed.ac.uk
Wed Jun 22 21:12:29 1994: Applied patches from Dave
(gentzel@nova.enet.dec.com) to prevent dereferencing
the NULL pointer, faith@cs.unc.edu
1999-02-22 Arkadiusz Mi¶kiewicz <misiek@misiek.eu.org>
- added Native Language Support
-------------------------------------------------------------------------
*/
#include <stdio.h>
#include "nls.h"
/* rdev.c - query/set root device. */
static void
usage(void) {
puts(_("usage: rdev [ -rsv ] [ -o OFFSET ] [ IMAGE [ VALUE [ OFFSET ] ] ]"));
puts(_(" rdev /dev/fd0 (or rdev /linux, etc.) displays the current ROOT device"));
puts(_(" rdev /dev/fd0 /dev/hda2 sets ROOT to /dev/hda2"));
puts(_(" rdev -R /dev/fd0 1 set the ROOTFLAGS (readonly status)"));
puts(_(" rdev -s /dev/fd0 /dev/hda2 set the SWAP device"));
puts(_(" rdev -r /dev/fd0 627 set the RAMDISK size"));
puts(_(" rdev -v /dev/fd0 1 set the bootup VIDEOMODE"));
puts(_(" rdev -o N ... use the byte offset N"));
puts(_(" rootflags ... same as rdev -R"));
puts(_(" swapdev ... same as rdev -s"));
puts(_(" ramsize ... same as rdev -r"));
puts(_(" vidmode ... same as rdev -v"));
puts(_("Note: video modes are: -3=Ask, -2=Extended, -1=NormalVga, 1=key1, 2=key2,..."));
puts(_(" use -R 1 to mount root readonly, -R 0 for read/write."));
exit(-1);
}
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <dirent.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#define DEFAULT_OFFSET 508
static void die(char *msg)
{
perror(msg);
exit(1);
}
static char *find_dev(int number)
{
DIR *dp;
struct dirent *dir;
static char name[PATH_MAX+1];
struct stat s;
if (!number) return "Boot device";
if ((dp = opendir("/dev")) == NULL) die("opendir /dev");
strcpy(name,"/dev/");
while ((dir = readdir(dp)) != NULL) {
strcpy(name+5,dir->d_name);
if (stat(name,&s) < 0)
continue;
if ((s.st_mode & S_IFMT) == S_IFBLK && s.st_rdev == number)
return name;
}
sprintf(name,"0x%04x",number);
return name;
}
/* enum { RDEV, SDEV, RAMSIZE, VIDMODE }; */
enum { RDEV, VIDMODE, RAMSIZE, SDEV, __syssize__, ROOTFLAGS };
char *cmdnames[6] = { "rdev", "vidmode", "ramsize", "swapdev",
"", "rootflags"};
char *desc[6] = { "Root device", "Video mode", "Ramsize", "Swap device",
"", "Root flags"};
#define shift(n) argv+=n,argc-=n
int main(int argc,char **argv)
{
int image,offset,dev_nr, i, newoffset=-1;
char *device, *ptr;
struct stat s;
int cmd = 0;
setlocale(LC_ALL, "");
bindtextdomain(PACKAGE, LOCALEDIR);
textdomain(PACKAGE);
device = NULL;
if ((ptr = strrchr(argv[0],'/')) != NULL)
ptr++;
else
ptr = argv[0];
for (i=0; i<=5; i++)
if (!strcmp(ptr,cmdnames[i]))
break;
cmd = i;
if (cmd>5)
cmd=RDEV;
offset = DEFAULT_OFFSET-cmd*2;
while (argc > 1)
{
if (argv[1][0] != '-')
break;
else
switch (argv[1][1])
{
case 'R':
cmd=ROOTFLAGS;
offset = DEFAULT_OFFSET-cmd*2;
shift(1);
break;
case 'r':
cmd=RAMSIZE;
offset = DEFAULT_OFFSET-cmd*2;
shift(1);
break;
case 'v':
cmd=VIDMODE;
offset = DEFAULT_OFFSET-cmd*2;
shift(1);
break;
case 's':
cmd=SDEV;
offset = DEFAULT_OFFSET-cmd*2;
shift(1);
break;
case 'o':
if (argv[1][2])
{
newoffset=atoi(argv[1]+2);
shift(1);
break;
} else if (argc > 2) {
newoffset=atoi(argv[2]);
shift(2);
break;
}
/* Fall through. . . */
default:
usage();
}
}
if (newoffset >= 0)
offset = newoffset;
if ((cmd==RDEV) && (argc == 1 || argc > 4)) {
if (stat("/",&s) < 0) die("/");
printf("%s /\n",find_dev(s.st_dev));
exit(0);
} else if ((cmd != RDEV) && (argc == 1 || argc > 4)) usage();
if ((cmd==RDEV) || (cmd==SDEV))
{
if (argc == 4) {
device = argv[2];
offset = atoi(argv[3]);
}
else {
if (argc == 3) {
if (isdigit(*argv[2])) offset = atoi(argv[2]);
else device = argv[2];
}
}
}
else
{
if (argc>=3)
device = argv[2];
if (argc==4)
offset = atoi(argv[3]);
}
if (device) {
if ((cmd==SDEV) || (cmd==RDEV))
{ if (stat(device,&s) < 0) die(device);
} else
s.st_rdev=atoi(device);
if ((image = open(argv[1],O_WRONLY)) < 0) die(argv[1]);
if (lseek(image,offset,0) < 0) die("lseek");
if (write(image,(char *)&s.st_rdev,2) != 2) die(argv[1]);
if (close(image) < 0) die("close");
}
else {
if ((image = open(argv[1],O_RDONLY)) < 0) die(argv[1]);
if (lseek(image,offset,0) < 0) die("lseek");
dev_nr = 0;
if (read(image,(char *)&dev_nr,2) != 2) die(argv[1]);
if (close(image) < 0) die("close");
printf(desc[cmd]);
if ((cmd==SDEV) || (cmd==RDEV))
printf(" %s\n", find_dev(dev_nr));
else
printf(" %d\n", dev_nr);
}
return 0;
}
|
