1/*
2 * Copyright (C) 2003 Greg Kroah-Hartman <greg@kroah.com>
3 * Copyright (C) 2004-2005 Kay Sievers <kay.sievers@vrfy.org>
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
21#include <stdlib.h>
22#include <stdio.h>
23#include <string.h>
24#include <stddef.h>
25#include <unistd.h>
26#include <fcntl.h>
27#include <string.h>
28#include <errno.h>
29#include <dirent.h>
30#include <sys/stat.h>
31#include <sys/types.h>
32
33#include "udev.h"
34
35
36static size_t devpath_to_db_path(const char *devpath, char *filename, size_t len)
37{
38	size_t start;
39
40	/* add location of db files */
41	strlcpy(filename, udev_root, len);
42	start = strlcat(filename, "/"DB_DIR"/", len);
43	strlcat(filename, devpath, len);
44	return path_encode(&filename[start], len - start);
45}
46
47/* reverse mapping from the device file name to the devpath */
48static int name_index(const char *devpath, const char *name, int add)
49{
50	char device[PATH_SIZE];
51	char filename[PATH_SIZE * 2];
52	size_t start;
53	int fd;
54
55	/* directory with device name */
56	strlcpy(filename, udev_root, sizeof(filename));
57	start = strlcat(filename, "/"DB_NAME_INDEX_DIR"/", sizeof(filename));
58	strlcat(filename, name, sizeof(filename));
59	path_encode(&filename[start], sizeof(filename) - start);
60	/* entry with the devpath */
61	strlcpy(device, devpath, sizeof(device));
62	path_encode(device, sizeof(device));
63	strlcat(filename, "/", sizeof(filename));
64	strlcat(filename, device, sizeof(filename));
65
66	if (add) {
67		info("creating index: '%s'", filename);
68		create_path(filename);
69		fd = open(filename, O_WRONLY|O_TRUNC|O_CREAT, 0644);
70		if (fd > 0)
71			close(fd);
72	} else {
73		info("removing index: '%s'", filename);
74		unlink(filename);
75		delete_path(filename);
76	}
77	return 0;
78}
79
80int udev_db_get_devices_by_name(const char *name, struct list_head *name_list)
81{
82	char dirname[PATH_MAX];
83	size_t start;
84	DIR *dir;
85	int rc = 0;
86
87	strlcpy(dirname, udev_root, sizeof(dirname));
88	start = strlcat(dirname, "/"DB_NAME_INDEX_DIR"/", sizeof(dirname));
89	strlcat(dirname, name, sizeof(dirname));
90	path_encode(&dirname[start], sizeof(dirname) - start);
91
92	dir = opendir(dirname);
93	if (dir == NULL) {
94		info("no index directory '%s': %s", dirname, strerror(errno));
95		rc = -1;
96		goto out;
97	}
98
99	info("found index directory '%s'", dirname);
100	while (1) {
101		struct dirent *ent;
102		char device[PATH_SIZE];
103
104		ent = readdir(dir);
105		if (ent == NULL || ent->d_name[0] == '\0')
106			break;
107		if (ent->d_name[0] == '.')
108			continue;
109
110		strlcpy(device, ent->d_name, sizeof(device));
111		path_decode(device);
112		name_list_add(name_list, device, 0);
113		rc++;
114	}
115	closedir(dir);
116out:
117	return rc;
118}
119
120int udev_db_add_device(struct udevice *udev)
121{
122	char filename[PATH_SIZE];
123
124	if (udev->test_run)
125		return 0;
126
127	devpath_to_db_path(udev->dev->devpath, filename, sizeof(filename));
128	create_path(filename);
129	unlink(filename);
130
131	/*
132	 * don't waste tmpfs memory pages, if we don't have any data to store
133	 * create fake db-file; store the node-name in a symlink target
134	 */
135	if (list_empty(&udev->symlink_list) && list_empty(&udev->env_list) &&
136	    !udev->partitions && !udev->ignore_remove) {
137		dbg("nothing interesting to store, create symlink");
138		if (symlink(udev->name, filename) != 0) {
139			err("unable to create db link '%s': %s", filename, strerror(errno));
140			return -1;
141		}
142	} else {
143		FILE *f;
144		struct name_entry *name_loop;
145
146		f = fopen(filename, "w");
147		if (f == NULL) {
148			err("unable to create db file '%s': %s", filename, strerror(errno));
149			return -1;
150		}
151		dbg("storing data for device '%s' in '%s'", udev->dev->devpath, filename);
152
153		fprintf(f, "N:%s\n", udev->name);
154		list_for_each_entry(name_loop, &udev->symlink_list, node) {
155			fprintf(f, "S:%s\n", name_loop->name);
156			/* add symlink-name to index */
157			name_index(udev->dev->devpath, name_loop->name, 1);
158		}
159		fprintf(f, "M:%u:%u\n", major(udev->devt), minor(udev->devt));
160		if (udev->link_priority != 0)
161			fprintf(f, "L:%u\n", udev->link_priority);
162		if (udev->partitions != 0)
163			fprintf(f, "A:%u\n", udev->partitions);
164		if (udev->ignore_remove)
165			fprintf(f, "R:%u\n", udev->ignore_remove);
166		list_for_each_entry(name_loop, &udev->env_list, node)
167			fprintf(f, "E:%s\n", name_loop->name);
168		fclose(f);
169	}
170
171	/* add name to index */
172	name_index(udev->dev->devpath, udev->name, 1);
173
174	return 0;
175}
176
177int udev_db_get_device(struct udevice *udev, const char *devpath)
178{
179	struct stat stats;
180	char filename[PATH_SIZE];
181	char line[PATH_SIZE];
182	unsigned int maj, min;
183	char *bufline;
184	char *buf;
185	size_t bufsize;
186	size_t cur;
187	size_t count;
188
189	sysfs_device_set_values(udev->dev, devpath, NULL, NULL);
190	devpath_to_db_path(devpath, filename, sizeof(filename));
191
192	if (lstat(filename, &stats) != 0) {
193		info("no db file to read %s: %s", filename, strerror(errno));
194		return -1;
195	}
196	if ((stats.st_mode & S_IFMT) == S_IFLNK) {
197		char target[NAME_SIZE];
198		int target_len;
199
200		info("found a symlink as db file");
201		target_len = readlink(filename, target, sizeof(target));
202		if (target_len > 0)
203			target[target_len] = '\0';
204		else {
205			info("error reading db link %s: %s", filename, strerror(errno));
206			return -1;
207		}
208		dbg("db link points to '%s'", target);
209		strlcpy(udev->name, target, sizeof(udev->name));
210		return 0;
211	}
212
213	if (file_map(filename, &buf, &bufsize) != 0) {
214		info("error reading db file %s: %s", filename, strerror(errno));
215		return -1;
216	}
217
218	cur = 0;
219	while (cur < bufsize) {
220		count = buf_get_line(buf, bufsize, cur);
221		bufline = &buf[cur];
222		cur += count+1;
223
224		switch(bufline[0]) {
225		case 'N':
226			if (count > sizeof(udev->name))
227				count = sizeof(udev->name);
228			memcpy(udev->name, &bufline[2], count-2);
229			udev->name[count-2] = '\0';
230			break;
231		case 'M':
232			if (count > sizeof(line))
233				count = sizeof(line);
234			memcpy(line, &bufline[2], count-2);
235			line[count-2] = '\0';
236			sscanf(line, "%u:%u", &maj, &min);
237			udev->devt = makedev(maj, min);
238			break;
239		case 'S':
240			if (count > sizeof(line))
241				count =  sizeof(line);
242			memcpy(line, &bufline[2], count-2);
243			line[count-2] = '\0';
244			name_list_add(&udev->symlink_list, line, 0);
245			break;
246		case 'L':
247			if (count > sizeof(line))
248				count =  sizeof(line);
249			memcpy(line, &bufline[2], count-2);
250			line[count-2] = '\0';
251			udev->link_priority = atoi(line);
252			break;
253		case 'A':
254			if (count > sizeof(line))
255				count =  sizeof(line);
256			memcpy(line, &bufline[2], count-2);
257			line[count-2] = '\0';
258			udev->partitions = atoi(line);
259			break;
260		case 'R':
261			if (count > sizeof(line))
262				count =  sizeof(line);
263			memcpy(line, &bufline[2], count-2);
264			line[count-2] = '\0';
265			udev->ignore_remove = atoi(line);
266			break;
267		case 'E':
268			if (count > sizeof(line))
269				count =  sizeof(line);
270			memcpy(line, &bufline[2], count-2);
271			line[count-2] = '\0';
272			name_list_add(&udev->env_list, line, 0);
273			break;
274		}
275	}
276	file_unmap(buf, bufsize);
277
278	if (udev->name[0] == '\0')
279		return -1;
280
281	return 0;
282}
283
284int udev_db_delete_device(struct udevice *udev)
285{
286	char filename[PATH_SIZE];
287	struct name_entry *name_loop;
288
289	if (udev->test_run)
290		return 0;
291
292	devpath_to_db_path(udev->dev->devpath, filename, sizeof(filename));
293	unlink(filename);
294
295	name_index(udev->dev->devpath, udev->name, 0);
296	list_for_each_entry(name_loop, &udev->symlink_list, node)
297		name_index(udev->dev->devpath, name_loop->name, 0);
298
299	return 0;
300}
301
302int udev_db_get_all_entries(struct list_head *name_list)
303{
304	char dbpath[PATH_MAX];
305	DIR *dir;
306
307	strlcpy(dbpath, udev_root, sizeof(dbpath));
308	strlcat(dbpath, "/"DB_DIR, sizeof(dbpath));
309	dir = opendir(dbpath);
310	if (dir == NULL) {
311		info("no udev_db available '%s': %s", dbpath, strerror(errno));
312		return -1;
313	}
314
315	while (1) {
316		struct dirent *ent;
317		char device[PATH_SIZE];
318
319		ent = readdir(dir);
320		if (ent == NULL || ent->d_name[0] == '\0')
321			break;
322		if (ent->d_name[0] == '.')
323			continue;
324
325		strlcpy(device, ent->d_name, sizeof(device));
326		path_decode(device);
327		name_list_add(name_list, device, 1);
328		dbg("added '%s'", device);
329	}
330
331	closedir(dir);
332	return 0;
333}
334