chiark / gitweb /
Fix libsysfs issue with relying on the detach_state file to be
[elogind.git] / udevstart.c
1 /*
2  * udevstart.c
3  *
4  * Copyright (C) 2004 Greg Kroah-Hartman <greg@kroah.com>
5  * 
6  * Quick and dirty way to populate a /dev with udev if your system
7  * does not have access to a shell.  Based originally on a patch to udev 
8  * from Harald Hoyer <harald@redhat.com>
9  *
10  *      This program is free software; you can redistribute it and/or modify it
11  *      under the terms of the GNU General Public License as published by the
12  *      Free Software Foundation version 2 of the License.
13  * 
14  *      This program is distributed in the hope that it will be useful, but
15  *      WITHOUT ANY WARRANTY; without even the implied warranty of
16  *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17  *      General Public License for more details.
18  * 
19  *      You should have received a copy of the GNU General Public License along
20  *      with this program; if not, write to the Free Software Foundation, Inc.,
21  *      675 Mass Ave, Cambridge, MA 02139, USA.
22  *
23  */
24
25 #include <stdlib.h>
26 #include <stddef.h>
27 #include <string.h>
28 #include <stdio.h>
29 #include <unistd.h>
30 #include <errno.h>
31 #include <ctype.h>
32 #include <dirent.h>
33 #include <signal.h>
34 #include <sys/wait.h>
35 #include <sys/stat.h>
36 #include <sys/types.h>
37
38 #include "libsysfs/sysfs/libsysfs.h"
39 #include "udev_libc_wrapper.h"
40 #include "udev.h"
41 #include "udev_version.h"
42 #include "logging.h"
43 #include "udev_rules.h"
44 #include "udev_utils.h"
45 #include "list.h"
46
47 #ifdef USE_LOG
48 void log_message(int priority, const char *format, ...)
49 {
50         va_list args;
51
52         if (priority > udev_log_priority)
53                 return;
54
55         va_start(args, format);
56         vsyslog(priority, format, args);
57         va_end(args);
58 }
59 #endif
60
61 struct device {
62         struct list_head node;
63         char path[PATH_SIZE];
64         char subsys[NAME_SIZE];
65 };
66
67 /* sort files in lexical order */
68 static int device_list_insert(const char *path, char *subsystem, struct list_head *device_list)
69 {
70         struct device *loop_device;
71         struct device *new_device;
72
73         dbg("insert: '%s'\n", path);
74
75         list_for_each_entry(loop_device, device_list, node) {
76                 if (strcmp(loop_device->path, path) > 0) {
77                         break;
78                 }
79         }
80
81         new_device = malloc(sizeof(struct device));
82         if (new_device == NULL) {
83                 dbg("error malloc");
84                 return -ENOMEM;
85         }
86
87         strlcpy(new_device->path, path, sizeof(new_device->path));
88         strlcpy(new_device->subsys, subsystem, sizeof(new_device->subsys));
89         list_add_tail(&new_device->node, &loop_device->node);
90         dbg("add '%s' from subsys '%s'", new_device->path, new_device->subsys);
91         return 0;
92 }
93
94 /* list of devices that we should run last due to any one of a number of reasons */
95 static char *last_list[] = {
96         "/block/dm",    /* on here because dm wants to have the block devices around before it */
97         NULL,
98 };
99
100 /* list of devices that we should run first due to any one of a number of reasons */
101 static char *first_list[] = {
102         "/class/mem",   /* people tend to like their memory devices around first... */
103         NULL,
104 };
105
106 static int add_device(const char *path, const char *subsystem)
107 {
108         struct udevice udev;
109         struct sysfs_class_device *class_dev;
110         const char *devpath;
111
112         devpath = &path[strlen(sysfs_path)];
113
114         /* set environment for callouts and dev.d/ */
115         setenv("DEVPATH", devpath, 1);
116         setenv("SUBSYSTEM", subsystem, 1);
117
118         dbg("exec: '%s' (%s)\n", devpath, path);
119
120         class_dev = sysfs_open_class_device_path(path);
121         if (class_dev == NULL) {
122                 dbg ("sysfs_open_class_device_path failed");
123                 return -ENODEV;
124         }
125
126         udev_init_device(&udev, devpath, subsystem, "add");
127         udev_add_device(&udev, class_dev);
128
129         if (udev.devname[0] != '\0')
130                 setenv("DEVNAME", udev.devname, 1);
131
132         if (udev_run && !list_empty(&udev.run_list)) {
133                 struct name_entry *name_loop;
134
135                 dbg("executing run list");
136                 list_for_each_entry(name_loop, &udev.run_list, node)
137                         execute_command(name_loop->name, udev.subsystem);
138         }
139
140         /* run dev.d/ scripts if we created a node or changed a netif name */
141         if (udev_dev_d && udev.devname[0] != '\0')
142                 udev_multiplex_directory(&udev, DEVD_DIR, DEVD_SUFFIX);
143
144         sysfs_close_class_device(class_dev);
145         udev_cleanup_device(&udev);
146
147         return 0;
148 }
149
150 static void exec_list(struct list_head *device_list)
151 {
152         struct device *loop_device;
153         struct device *tmp_device;
154         int i;
155
156         /* handle the "first" type devices first */
157         list_for_each_entry_safe(loop_device, tmp_device, device_list, node) {
158                 for (i = 0; first_list[i] != NULL; i++) {
159                         if (strncmp(loop_device->path, first_list[i], strlen(first_list[i])) == 0) {
160                                 add_device(loop_device->path, loop_device->subsys);
161                                 list_del(&loop_device->node);
162                                 free(loop_device);
163                                 break;
164                         }
165                 }
166         }
167
168         /* handle the devices we are allowed to, excluding the "last" type devices */
169         list_for_each_entry_safe(loop_device, tmp_device, device_list, node) {
170                 int found = 0;
171                 for (i = 0; last_list[i] != NULL; i++) {
172                         if (strncmp(loop_device->path, last_list[i], strlen(last_list[i])) == 0) {
173                                 found = 1;
174                                 break;
175                         }
176                 }
177                 if (found)
178                         continue;
179
180                 add_device(loop_device->path, loop_device->subsys);
181                 list_del(&loop_device->node);
182                 free(loop_device);
183         }
184
185         /* handle the rest of the devices left over, if any */
186         list_for_each_entry_safe(loop_device, tmp_device, device_list, node) {
187                 add_device(loop_device->path, loop_device->subsys);
188                 list_del(&loop_device->node);
189                 free(loop_device);
190         }
191 }
192
193 static int has_devt(const char *directory)
194 {
195         char filename[PATH_SIZE];
196         struct stat statbuf;
197
198         snprintf(filename, sizeof(filename), "%s/dev", directory);
199         filename[sizeof(filename)-1] = '\0';
200
201         if (stat(filename, &statbuf) == 0)
202                 return 1;
203
204         return 0;
205 }
206
207 static void udev_scan_block(void)
208 {
209         char base[PATH_SIZE];
210         DIR *dir;
211         struct dirent *dent;
212         LIST_HEAD(device_list);
213
214         snprintf(base, sizeof(base), "%s/block", sysfs_path);
215         base[sizeof(base)-1] = '\0';
216
217         dir = opendir(base);
218         if (dir != NULL) {
219                 for (dent = readdir(dir); dent != NULL; dent = readdir(dir)) {
220                         char dirname[PATH_SIZE];
221                         DIR *dir2;
222                         struct dirent *dent2;
223
224                         if (dent->d_name[0] == '.')
225                                 continue;
226
227                         snprintf(dirname, sizeof(dirname), "%s/%s", base, dent->d_name);
228                         dirname[sizeof(dirname)-1] = '\0';
229                         if (has_devt(dirname))
230                                 device_list_insert(dirname, "block", &device_list);
231                         else
232                                 continue;
233
234                         /* look for partitions */
235                         dir2 = opendir(dirname);
236                         if (dir2 != NULL) {
237                                 for (dent2 = readdir(dir2); dent2 != NULL; dent2 = readdir(dir2)) {
238                                         char dirname2[PATH_SIZE];
239
240                                         if (dent2->d_name[0] == '.')
241                                                 continue;
242
243                                         snprintf(dirname2, sizeof(dirname2), "%s/%s", dirname, dent2->d_name);
244                                         dirname2[sizeof(dirname2)-1] = '\0';
245
246                                         if (has_devt(dirname2))
247                                                 device_list_insert(dirname2, "block", &device_list);
248                                 }
249                                 closedir(dir2);
250                         }
251                 }
252                 closedir(dir);
253         }
254         exec_list(&device_list);
255 }
256
257 static void udev_scan_class(void)
258 {
259         char base[PATH_SIZE];
260         DIR *dir;
261         struct dirent *dent;
262         LIST_HEAD(device_list);
263
264         snprintf(base, sizeof(base), "%s/class", sysfs_path);
265         base[sizeof(base)-1] = '\0';
266
267         dir = opendir(base);
268         if (dir != NULL) {
269                 for (dent = readdir(dir); dent != NULL; dent = readdir(dir)) {
270                         char dirname[PATH_SIZE];
271                         DIR *dir2;
272                         struct dirent *dent2;
273
274                         if (dent->d_name[0] == '.')
275                                 continue;
276
277                         snprintf(dirname, sizeof(dirname), "%s/%s", base, dent->d_name);
278                         dirname[sizeof(dirname)-1] = '\0';
279
280                         dir2 = opendir(dirname);
281                         if (dir2 != NULL) {
282                                 for (dent2 = readdir(dir2); dent2 != NULL; dent2 = readdir(dir2)) {
283                                         char dirname2[PATH_SIZE];
284
285                                         if (dent2->d_name[0] == '.')
286                                                 continue;
287
288                                         snprintf(dirname2, sizeof(dirname2), "%s/%s", dirname, dent2->d_name);
289                                         dirname2[sizeof(dirname2)-1] = '\0';
290
291                                         /* pass the net class as it is */
292                                         if (strcmp(dent->d_name, "net") == 0)
293                                                 device_list_insert(dirname2, "net", &device_list);
294                                         else if (has_devt(dirname2))
295                                                 device_list_insert(dirname2, dent->d_name, &device_list);
296                                 }
297                                 closedir(dir2);
298                         }
299                 }
300                 closedir(dir);
301         }
302         exec_list(&device_list);
303 }
304
305 static void asmlinkage sig_handler(int signum)
306 {
307         switch (signum) {
308                 case SIGALRM:
309                         exit(1);
310                 case SIGINT:
311                 case SIGTERM:
312                         exit(20 + signum);
313         }
314 }
315
316 int main(int argc, char *argv[], char *envp[])
317 {
318         struct sigaction act;
319
320         logging_init("udev");
321         udev_init_config();
322         /* disable all logging if not explicitely requested */
323         if (getenv("UDEV_LOG") == NULL)
324                 udev_log_priority = 0;
325         dbg("version %s", UDEV_VERSION);
326
327         /* set signal handlers */
328         memset(&act, 0x00, sizeof(act));
329         act.sa_handler = (void (*) (int))sig_handler;
330         sigemptyset (&act.sa_mask);
331         act.sa_flags = 0;
332         sigaction(SIGALRM, &act, NULL);
333         sigaction(SIGINT, &act, NULL);
334         sigaction(SIGTERM, &act, NULL);
335
336         /* trigger timeout to prevent hanging processes */
337         alarm(ALARM_TIMEOUT);
338
339         /* set environment for executed programs */
340         setenv("ACTION", "add", 1);
341         setenv("UDEV_START", "1", 1);
342
343         udev_rules_init();
344
345         udev_scan_block();
346         udev_scan_class();
347
348         logging_close();
349         return 0;
350 }