1/*
2 * Copyright (C) 2004-2006 Kay Sievers <kay@vrfy.org>
3 * Copyright (C) 2006 Hannes Reinecke <hare@suse.de>
4 *
5 *	This program is free software; you can redistribute it and/or modify it
6 *	under the terms of the GNU General Public License as published by the
7 *	Free Software Foundation version 2 of the License.
8 *
9 *	This program is distributed in the hope that it will be useful, but
10 *	WITHOUT ANY WARRANTY; without even the implied warranty of
11 *	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12 *	General Public License for more details.
13 *
14 *	You should have received a copy of the GNU General Public License along
15 *	with this program; if not, write to the Free Software Foundation, Inc.,
16 *	51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
17 *
18 */
19
20#include <stdlib.h>
21#include <stddef.h>
22#include <stdarg.h>
23#include <string.h>
24#include <stdio.h>
25#include <unistd.h>
26#include <getopt.h>
27#include <errno.h>
28#include <dirent.h>
29#include <fcntl.h>
30#include <syslog.h>
31#include <sys/stat.h>
32#include <sys/types.h>
33
34#define PATH_SIZE 512
35
36static int verbose;
37static int dry_run;
38
39void log_message(int priority, const char *format, ...)
40{
41	va_list args;
42
43	va_start(args, format);
44	vsyslog(priority, format, args);
45	va_end(args);
46}
47
48#undef err
49#define err(format, arg...)                         \
50    do {                                    \
51        log_message(LOG_ERR ,"%s: " format ,__FUNCTION__ ,## arg);  \
52    } while (0)
53
54#undef info
55#define info(format, arg...)                            \
56    do {                                    \
57        log_message(LOG_INFO ,"%s: " format ,__FUNCTION__ ,## arg); \
58    } while (0)
59
60#ifdef DEBUG
61#undef dbg
62#define dbg(format, arg...)                         \
63    do {                                    \
64        log_message(LOG_DEBUG ,"%s: " format ,__FUNCTION__ ,## arg);    \
65    } while (0)
66#else
67#define dbg(...) do {} while(0)
68#endif
69
70
71static void trigger_uevent(const char *devpath)
72{
73	char filename[PATH_SIZE];
74	int fd;
75
76	strlcpy(filename, "/sys", sizeof(filename));
77	strlcat(filename, devpath, sizeof(filename));
78	strlcat(filename, "/uevent", sizeof(filename));
79
80	if (verbose)
81		printf("%s\n", devpath);
82
83	if (dry_run)
84		return;
85
86	fd = open(filename, O_WRONLY);
87	if (fd < 0) {
88		dbg("error on opening %s: %s\n", filename, strerror(errno));
89		return;
90	}
91
92	if (write(fd, "add", 3) < 0)
93		info("error on triggering %s: %s\n", filename, strerror(errno));
94
95	close(fd);
96}
97
98static int sysfs_resolve_link(char *devpath, size_t size)
99{
100	char link_path[PATH_SIZE];
101	char link_target[PATH_SIZE];
102	int len;
103	int i;
104	int back;
105
106	strlcpy(link_path, "/sys", sizeof(link_path));
107	strlcat(link_path, devpath, sizeof(link_path));
108	len = readlink(link_path, link_target, sizeof(link_target));
109	if (len <= 0)
110		return -1;
111	link_target[len] = '\0';
112	dbg("path link '%s' points to '%s'", devpath, link_target);
113
114	for (back = 0; strncmp(&link_target[back * 3], "../", 3) == 0; back++)
115		;
116	dbg("base '%s', tail '%s', back %i", devpath, &link_target[back * 3], back);
117	for (i = 0; i <= back; i++) {
118		char *pos = strrchr(devpath, '/');
119
120		if (pos == NULL)
121			return -1;
122		pos[0] = '\0';
123	}
124	dbg("after moving back '%s'", devpath);
125	strlcat(devpath, "/", size);
126	strlcat(devpath, &link_target[back * 3], size);
127	return 0;
128}
129
130
131static int device_list_insert(const char *path)
132{
133	char filename[PATH_SIZE];
134	char devpath[PATH_SIZE];
135	struct stat statbuf;
136
137	dbg("add '%s'" , path);
138
139	/* we only have a device, if we have an uevent file */
140	strlcpy(filename, path, sizeof(filename));
141	strlcat(filename, "/uevent", sizeof(filename));
142	if (stat(filename, &statbuf) < 0)
143		return -1;
144	if (!(statbuf.st_mode & S_IWUSR))
145		return -1;
146
147	strlcpy(devpath, &path[4], sizeof(devpath));
148
149	/* resolve possible link to real target */
150	if (lstat(path, &statbuf) < 0)
151		return -1;
152	if (S_ISLNK(statbuf.st_mode))
153		if (sysfs_resolve_link(devpath, sizeof(devpath)) != 0)
154			return -1;
155
156	trigger_uevent(devpath);
157	return 0;
158}
159
160
161static void scan_subsystem(const char *subsys)
162{
163	char base[PATH_SIZE];
164	DIR *dir;
165	struct dirent *dent;
166
167	strlcpy(base, "/sys/", sizeof(base));
168	strlcat(base, subsys, sizeof(base));
169
170	dir = opendir(base);
171	if (dir != NULL) {
172		for (dent = readdir(dir); dent != NULL; dent = readdir(dir)) {
173			char dirname[PATH_SIZE];
174			DIR *dir2;
175			struct dirent *dent2;
176
177			if (dent->d_name[0] == '.')
178				continue;
179
180			strlcpy(dirname, base, sizeof(dirname));
181			strlcat(dirname, "/", sizeof(dirname));
182			strlcat(dirname, dent->d_name, sizeof(dirname));
183			strlcat(dirname, "/devices", sizeof(dirname));
184
185			/* look for devices */
186			dir2 = opendir(dirname);
187			if (dir2 != NULL) {
188				for (dent2 = readdir(dir2); dent2 != NULL; dent2 = readdir(dir2)) {
189					char dirname2[PATH_SIZE];
190
191					if (dent2->d_name[0] == '.')
192						continue;
193
194					strlcpy(dirname2, dirname, sizeof(dirname2));
195					strlcat(dirname2, "/", sizeof(dirname2));
196					strlcat(dirname2, dent2->d_name, sizeof(dirname2));
197					device_list_insert(dirname2);
198				}
199				closedir(dir2);
200			}
201		}
202		closedir(dir);
203	}
204}
205
206static void scan_block(void)
207{
208	char base[PATH_SIZE];
209	DIR *dir;
210	struct dirent *dent;
211
212	strlcpy(base, "/sys/block", sizeof(base));
213
214	dir = opendir(base);
215	if (dir != NULL) {
216		for (dent = readdir(dir); dent != NULL; dent = readdir(dir)) {
217			char dirname[PATH_SIZE];
218			DIR *dir2;
219			struct dirent *dent2;
220
221			if (dent->d_name[0] == '.')
222				continue;
223
224			strlcpy(dirname, base, sizeof(dirname));
225			strlcat(dirname, "/", sizeof(dirname));
226			strlcat(dirname, dent->d_name, sizeof(dirname));
227			if (device_list_insert(dirname) != 0)
228				continue;
229
230			/* look for partitions */
231			dir2 = opendir(dirname);
232			if (dir2 != NULL) {
233				for (dent2 = readdir(dir2); dent2 != NULL; dent2 = readdir(dir2)) {
234					char dirname2[PATH_SIZE];
235
236					if (dent2->d_name[0] == '.')
237						continue;
238
239					if (!strcmp(dent2->d_name,"device"))
240						continue;
241
242					strlcpy(dirname2, dirname, sizeof(dirname2));
243					strlcat(dirname2, "/", sizeof(dirname2));
244					strlcat(dirname2, dent2->d_name, sizeof(dirname2));
245					device_list_insert(dirname2);
246				}
247				closedir(dir2);
248			}
249		}
250		closedir(dir);
251	}
252}
253
254static void scan_class(void)
255{
256	char base[PATH_SIZE];
257	DIR *dir;
258	struct dirent *dent;
259
260	strlcpy(base, "/sys/class", sizeof(base));
261
262	dir = opendir(base);
263	if (dir != NULL) {
264		for (dent = readdir(dir); dent != NULL; dent = readdir(dir)) {
265			char dirname[PATH_SIZE];
266			DIR *dir2;
267			struct dirent *dent2;
268
269			if (dent->d_name[0] == '.')
270				continue;
271
272			strlcpy(dirname, base, sizeof(dirname));
273			strlcat(dirname, "/", sizeof(dirname));
274			strlcat(dirname, dent->d_name, sizeof(dirname));
275			dir2 = opendir(dirname);
276			if (dir2 != NULL) {
277				for (dent2 = readdir(dir2); dent2 != NULL; dent2 = readdir(dir2)) {
278					char dirname2[PATH_SIZE];
279
280					if (dent2->d_name[0] == '.')
281						continue;
282
283					if (!strcmp(dent2->d_name, "device"))
284						continue;
285
286					strlcpy(dirname2, dirname, sizeof(dirname2));
287					strlcat(dirname2, "/", sizeof(dirname2));
288					strlcat(dirname2, dent2->d_name, sizeof(dirname2));
289					device_list_insert(dirname2);
290				}
291				closedir(dir2);
292			}
293		}
294		closedir(dir);
295	}
296}
297
298int main(int argc, char *argv[], char *envp[])
299{
300	char base[PATH_SIZE];
301	struct stat statbuf;
302	int failed = 0;
303	int option;
304
305	openlog("udevtrigger", LOG_PID | LOG_CONS, LOG_DAEMON);
306
307	while (1) {
308		option = getopt(argc, argv, "vnh");
309		if (option == -1)
310			break;
311
312		switch (option) {
313		case 'v':
314			verbose = 1;
315			break;
316		case 'n':
317			dry_run = 1;
318			break;
319		case 'h':
320			printf("Usage: udevtrigger OPTIONS\n"
321			       "  -v                     print the list of devices while running\n"
322			       "  -n                     do not actually trigger the events\n"
323			       "  -h                     print this text\n"
324			       "\n");
325			goto exit;
326		default:
327			goto exit;
328		}
329	}
330
331
332	/* if we have /sys/subsystem, forget all the old stuff */
333	scan_subsystem("bus");
334	scan_class();
335
336	/* scan "block" if it isn't a "class" */
337	strlcpy(base, "/sys/class/block", sizeof(base));
338	if (stat(base, &statbuf) != 0)
339		scan_block();
340
341exit:
342
343	closelog();
344	return 0;
345}
346