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
|
/*
* udev-add.c
*
* Userspace devfs
*
* Copyright (C) 2003 Greg Kroah-Hartman <greg@kroah.com>
*
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation version 2 of the License.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 675 Mass Ave, Cambridge, MA 02139, USA.
*
*/
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <fcntl.h>
#include <unistd.h>
#include <errno.h>
#include "udev.h"
#include "udev_version.h"
#include "namedev.h"
#include "libsysfs/libsysfs.h"
static char sysfs_path[SYSFS_PATH_MAX];
/*
* Right now the major/minor of a device is stored in a file called
* "dev" in sysfs.
* The number is stored as:
* MMmm
* MM is the major
* mm is the minor
* The value is in hex.
* Yes, this will probably change when we go to a bigger major/minor
* range, and will have to be changed at that time.
*/
static int get_major_minor(struct sysfs_class_device *class_dev, int *major, int *minor)
{
int retval = -ENODEV;
char *dev;
dev = sysfs_get_value_from_attributes(class_dev->directory->attributes, "dev");
if (dev == NULL)
goto exit;
dbg("dev = %s", dev);
if (sscanf(dev, "%u:%u", major, minor) != 2)
goto exit;
dbg("found major = %d, minor = %d", *major, *minor);
retval = 0;
exit:
return retval;
}
/*
* We also want to add some permissions here, and possibly some symlinks
*/
static int create_node(char *name, char type, int major, int minor, int mode)
{
char *argv[7];
char mode_string[100];
char type_string[3];
char major_string[20];
char minor_string[20];
char filename[255];
int retval = 0;
strncpy(filename, UDEV_ROOT, sizeof(filename));
strncat(filename, name, sizeof(filename));
snprintf(mode_string, sizeof(mode_string), "--mode=%#o", mode);
snprintf(type_string, sizeof(type_string), "%c", type);
snprintf(major_string, sizeof(major_string), "%d", major);
snprintf(minor_string, sizeof(minor_string), "%d", minor);
argv[0] = MKNOD;
argv[1] = mode_string;
argv[2] = filename;
argv[3] = type_string;
argv[4] = major_string;
argv[5] = minor_string;
argv[6] = NULL;
dbg ("executing %s %s %s %s %s %s",
argv[0], argv[1], argv[2], argv[3], argv[4], argv[5]);
switch (fork()) {
case 0:
/* we are the child, so lets run the program */
execv (MKNOD, argv);
exit(0);
break;
case (-1):
dbg ("fork failed.");
retval = -EFAULT;
break;
default:
break;
}
return retval;
}
struct sysfs_class_device *get_class_dev(char *device_name)
{
char dev_path[SYSFS_PATH_MAX];
struct sysfs_class_device *class_dev;
strcpy(dev_path, sysfs_path);
strcat(dev_path, device_name);
dbg("looking at %s", dev_path);
/* open up the sysfs class device for this thing... */
class_dev = sysfs_open_class_device(dev_path);
if (class_dev == NULL) {
dbg ("sysfs_open_class_device failed");
return NULL;
}
dbg("class_dev->name = %s", class_dev->name);
return class_dev;
}
static int udev_init(void)
{
int retval;
retval = sysfs_get_mnt_path(sysfs_path, SYSFS_PATH_MAX);
dbg("sysfs_path = %s", sysfs_path);
return retval;
}
int udev_add_device(char *device, char *subsystem)
{
struct sysfs_class_device *class_dev;
struct device_attr attr;
//char *name;
int major;
int minor;
char type;
//int mode;
int retval = -EINVAL;
/* sleep for a second or two to give the kernel a chance to
* create the dev file
*/
sleep(1);
udev_init();
/* for now, the block layer is the only place where block devices are */
if (strcmp(subsystem, "block") == 0)
type = 'b';
else
type = 'c';
class_dev = get_class_dev(device);
if (class_dev == NULL)
goto exit;
retval = namedev_name_device(class_dev, &attr);
if (retval)
return retval;
retval = get_major_minor(class_dev, &major, &minor);
if (retval) {
dbg ("get_major_minor failed");
goto exit;
}
sysfs_close_class_device(class_dev);
return create_node(attr.name, type, major, minor, attr.mode);
exit:
return retval;
}
|
