chiark / gitweb /
libudev: device - add devtype support
[elogind.git] / udev / lib / libudev-device.c
1 /*
2  * libudev - interface to udev device information
3  *
4  * Copyright (C) 2008 Kay Sievers <kay.sievers@vrfy.org>
5  *
6  * This program is free software: you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation, either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
18  */
19
20 #include <stdio.h>
21 #include <stdlib.h>
22 #include <stddef.h>
23 #include <unistd.h>
24 #include <errno.h>
25 #include <string.h>
26 #include <dirent.h>
27 #include <fcntl.h>
28 #include <ctype.h>
29 #include <sys/stat.h>
30
31 #include "libudev.h"
32 #include "libudev-private.h"
33
34 struct udev_device {
35         struct udev *udev;
36         struct udev_device *parent_device;
37         char *syspath;
38         const char *devpath;
39         char *sysname;
40         const char *sysnum;
41         char *devnode;
42         char *subsystem;
43         char *devtype;
44         char *driver;
45         char *action;
46         char *devpath_old;
47         char *physdevpath;
48         char **envp;
49         char *monitor_buf;
50         size_t monitor_buf_len;
51         struct udev_list_node devlinks_list;
52         struct udev_list_node properties_list;
53         struct udev_list_node sysattr_list;
54         unsigned long long int seqnum;
55         int event_timeout;
56         int timeout;
57         int num_fake_partitions;
58         int devlink_priority;
59         int refcount;
60         dev_t devnum;
61         unsigned int parent_set:1;
62         unsigned int subsystem_set:1;
63         unsigned int devtype_set:1;
64         unsigned int devlinks_uptodate:1;
65         unsigned int envp_uptodate:1;
66         unsigned int driver_set:1;
67         unsigned int info_loaded:1;
68         unsigned int ignore_remove:1;
69 };
70
71 static size_t devpath_to_db_path(struct udev *udev, const char *devpath, char *filename, size_t len)
72 {
73         size_t start;
74
75         /* translate to location of db file */
76         util_strlcpy(filename, udev_get_dev_path(udev), len);
77         start = util_strlcat(filename, "/.udev/db/", len);
78         util_strlcat(filename, devpath, len);
79         return util_path_encode(&filename[start], len - start);
80 }
81
82 int udev_device_read_db(struct udev_device *udev_device)
83 {
84         struct stat stats;
85         char filename[UTIL_PATH_SIZE];
86         char line[UTIL_LINE_SIZE];
87         FILE *f;
88
89         devpath_to_db_path(udev_device->udev, udev_device->devpath, filename, sizeof(filename));
90
91         if (lstat(filename, &stats) != 0) {
92                 dbg(udev_device->udev, "no db file to read %s: %m\n", filename);
93                 return -1;
94         }
95         if ((stats.st_mode & S_IFMT) == S_IFLNK) {
96                 char target[UTIL_PATH_SIZE];
97                 char devnode[UTIL_PATH_SIZE];
98                 int target_len;
99                 char *next;
100
101                 target_len = readlink(filename, target, sizeof(target));
102                 if (target_len > 0)
103                         target[target_len] = '\0';
104                 else {
105                         dbg(udev_device->udev, "error reading db link %s: %m\n", filename);
106                         return -1;
107                 }
108
109                 next = strchr(target, ' ');
110                 if (next != NULL) {
111                         next[0] = '\0';
112                         next = &next[1];
113                 }
114                 util_strlcpy(devnode, udev_get_dev_path(udev_device->udev), sizeof(devnode));
115                 util_strlcat(devnode, "/", sizeof(devnode));
116                 util_strlcat(devnode, target, sizeof(devnode));
117                 udev_device_set_devnode(udev_device, devnode);
118                 while (next != NULL) {
119                         char devlink[UTIL_PATH_SIZE];
120                         const char *lnk;
121
122                         lnk = next;
123                         next = strchr(next, ' ');
124                         if (next != NULL) {
125                                 next[0] = '\0';
126                                 next = &next[1];
127                         }
128                         util_strlcpy(devlink, udev_get_dev_path(udev_device->udev), sizeof(devlink));
129                         util_strlcat(devlink, "/", sizeof(devlink));
130                         util_strlcat(devlink, lnk, sizeof(devlink));
131                         udev_device_add_devlink(udev_device, devlink);
132                 }
133                 info(udev_device->udev, "device %p filled with db symlink data '%s'\n", udev_device, udev_device->devnode);
134                 return 0;
135         }
136
137         f = fopen(filename, "r");
138         if (f == NULL) {
139                 dbg(udev_device->udev, "error reading db file %s: %m\n", filename);
140                 return -1;
141         }
142         while (fgets(line, sizeof(line), f)) {
143                 ssize_t len;
144                 const char *val;
145
146                 len = strlen(line);
147                 if (len < 4)
148                         break;
149                 line[len-1] = '\0';
150                 val = &line[2];
151                 switch(line[0]) {
152                 case 'N':
153                         util_strlcpy(filename, udev_get_dev_path(udev_device->udev), sizeof(filename));
154                         util_strlcat(filename, "/", sizeof(filename));
155                         util_strlcat(filename, val, sizeof(filename));
156                         udev_device_set_devnode(udev_device, filename);
157                         break;
158                 case 'S':
159                         util_strlcpy(filename, udev_get_dev_path(udev_device->udev), sizeof(filename));
160                         util_strlcat(filename, "/", sizeof(filename));
161                         util_strlcat(filename, val, sizeof(filename));
162                         udev_device_add_devlink(udev_device, filename);
163                         break;
164                 case 'L':
165                         udev_device_set_devlink_priority(udev_device, atoi(val));
166                         break;
167                 case 'T':
168                         udev_device_set_event_timeout(udev_device, atoi(val));
169                         break;
170                 case 'A':
171                         udev_device_set_num_fake_partitions(udev_device, atoi(val));
172                         break;
173                 case 'R':
174                         udev_device_set_ignore_remove(udev_device, atoi(val));
175                         break;
176                 case 'E':
177                         udev_device_add_property_from_string(udev_device, val);
178                         break;
179                 }
180         }
181         fclose(f);
182
183         info(udev_device->udev, "device %p filled with db file data\n", udev_device);
184         return 0;
185 }
186
187 int udev_device_read_uevent_file(struct udev_device *udev_device)
188 {
189         char filename[UTIL_PATH_SIZE];
190         FILE *f;
191         char line[UTIL_LINE_SIZE];
192         int maj = 0;
193         int min = 0;
194
195         util_strlcpy(filename, udev_device->syspath, sizeof(filename));
196         util_strlcat(filename, "/uevent", sizeof(filename));
197         f = fopen(filename, "r");
198         if (f == NULL)
199                 return -1;
200
201         while (fgets(line, sizeof(line), f)) {
202                 char *pos;
203
204                 pos = strchr(line, '\n');
205                 if (pos == NULL)
206                         continue;
207                 pos[0] = '\0';
208
209                 if (strncmp(line, "DEVTYPE=", 8) == 0)
210                         udev_device_set_devtype(udev_device, &line[8]);
211                 else if (strncmp(line, "MAJOR=", 6) == 0)
212                         maj = strtoull(&line[6], NULL, 10);
213                 else if (strncmp(line, "MINOR=", 6) == 0)
214                         min = strtoull(&line[6], NULL, 10);
215
216                 udev_device_add_property_from_string(udev_device, line);
217         }
218
219         udev_device->devnum = makedev(maj, min);
220
221         fclose(f);
222         return 0;
223 }
224
225 static void device_load_info(struct udev_device *device)
226 {
227         device->info_loaded = 1;
228         udev_device_read_uevent_file(device);
229         udev_device_read_db(device);
230 }
231
232 void udev_device_set_info_loaded(struct udev_device *device)
233 {
234         device->info_loaded = 1;
235 }
236
237 struct udev_device *device_new(struct udev *udev)
238 {
239         struct udev_device *udev_device;
240         struct udev_list_entry *list_entry;
241
242         if (udev == NULL)
243                 return NULL;
244
245         udev_device = calloc(1, sizeof(struct udev_device));
246         if (udev_device == NULL)
247                 return NULL;
248         udev_device->refcount = 1;
249         udev_device->udev = udev;
250         udev_list_init(&udev_device->devlinks_list);
251         udev_list_init(&udev_device->properties_list);
252         udev_list_init(&udev_device->sysattr_list);
253         udev_device->event_timeout = -1;
254         /* copy global properties */
255         udev_list_entry_foreach(list_entry, udev_get_properties_list_entry(udev))
256                 udev_device_add_property(udev_device,
257                                          udev_list_entry_get_name(list_entry),
258                                          udev_list_entry_get_value(list_entry));
259         dbg(udev_device->udev, "udev_device: %p created\n", udev_device);
260         return udev_device;
261 }
262
263 /**
264  * udev_device_new_from_syspath:
265  * @udev: udev library context
266  * @syspath: sys device path including sys directory
267  *
268  * Create new udev device, and fill in information from the sys
269  * device and the udev database entry. The sypath is the absolute
270  * path to the device, including the sys mount point.
271  *
272  * The initial refcount is 1, and needs to be decremented to
273  * release the resources of the udev device.
274  *
275  * Returns: a new udev device, or #NULL, if it does not exist
276  **/
277 struct udev_device *udev_device_new_from_syspath(struct udev *udev, const char *syspath)
278 {
279         size_t len;
280         const char *subdir;
281         char path[UTIL_PATH_SIZE];
282         char *pos;
283         struct stat statbuf;
284         struct udev_device *udev_device;
285
286         if (udev == NULL)
287                 return NULL;
288         if (syspath == NULL)
289                 return NULL;
290
291         /* path starts in sys */
292         len = strlen(udev_get_sys_path(udev));
293         if (strncmp(syspath, udev_get_sys_path(udev), len) != 0) {
294                 info(udev, "not in sys :%s\n", syspath);
295                 return NULL;
296         }
297
298         /* path is not a root directory */
299         subdir = &syspath[len+1];
300         pos = strrchr(subdir, '/');
301         if (pos == NULL || pos < &subdir[2]) {
302                 dbg(udev, "not a subdir :%s\n", syspath);
303                 return NULL;
304         }
305
306         /* resolve possible symlink to real path */
307         util_strlcpy(path, syspath, sizeof(path));
308         util_resolve_sys_link(udev, path, sizeof(path));
309
310         /* try to resolve the silly block layout if needed */
311         if (strncmp(&path[len], "/block/", 7) == 0) {
312                 char block[UTIL_PATH_SIZE];
313                 char part[UTIL_PATH_SIZE];
314
315                 util_strlcpy(block, path, sizeof(block));
316                 pos = strrchr(block, '/');
317                 if (pos == NULL)
318                         return NULL;
319                 util_strlcpy(part, pos, sizeof(part));
320                 pos[0] = '\0';
321                 if (util_resolve_sys_link(udev, block, sizeof(block)) == 0) {
322                         util_strlcpy(path, block, sizeof(path));
323                         util_strlcat(path, part, sizeof(path));
324                 }
325         }
326
327         /* path exists in sys */
328         if (strncmp(&syspath[len], "/devices/", 9) == 0 ||
329             strncmp(&syspath[len], "/class/", 7) == 0 ||
330             strncmp(&syspath[len], "/block/", 7) == 0) {
331                 char file[UTIL_PATH_SIZE];
332
333                 /* all "devices" require a "uevent" file */
334                 util_strlcpy(file, path, sizeof(file));
335                 util_strlcat(file, "/uevent", sizeof(file));
336                 if (stat(file, &statbuf) != 0) {
337                         dbg(udev, "not a device: %s\n", syspath);
338                         return NULL;
339                 }
340         } else {
341                 /* everything else just needs to be a directory */
342                 if (stat(path, &statbuf) != 0 || !S_ISDIR(statbuf.st_mode)) {
343                         dbg(udev, "directory not found: %s\n", syspath);
344                         return NULL;
345                 }
346         }
347
348         udev_device = device_new(udev);
349         if (udev_device == NULL)
350                 return NULL;
351
352         udev_device_set_syspath(udev_device, path);
353         info(udev, "device %p has devpath '%s'\n", udev_device, udev_device_get_devpath(udev_device));
354
355         return udev_device;
356 }
357
358 struct udev_device *udev_device_new_from_devnum(struct udev *udev, char type, dev_t devnum)
359 {
360         char path[UTIL_PATH_SIZE];
361         const char *type_str;
362         struct udev_enumerate *udev_enumerate;
363         struct udev_list_entry *list_entry;
364         struct udev_device *device = NULL;
365
366         if (type == 'b')
367                 type_str = "block";
368         else if (type == 'c')
369                 type_str = "char";
370         else
371                 return NULL;
372
373         /* /sys/dev/{block,char}/<maj>:<min> link */
374         snprintf(path, sizeof(path), "%s/dev/%s/%u:%u", udev_get_sys_path(udev),
375                  type_str, major(devnum), minor(devnum));
376         if (util_resolve_sys_link(udev, path, sizeof(path)) == 0)
377                 return udev_device_new_from_syspath(udev, path);
378
379         udev_enumerate = udev_enumerate_new(udev);
380         if (udev_enumerate == NULL)
381                 return NULL;
382
383         /* fallback to search sys devices for the major/minor */
384         if (type == 'b')
385                 udev_enumerate_add_match_subsystem(udev_enumerate, "block");
386         else if (type == 'c')
387                 udev_enumerate_add_nomatch_subsystem(udev_enumerate, "block");
388         udev_enumerate_scan_devices(udev_enumerate);
389         udev_list_entry_foreach(list_entry, udev_enumerate_get_list_entry(udev_enumerate)) {
390                 struct udev_device *device_loop;
391
392                 device_loop = udev_device_new_from_syspath(udev, udev_list_entry_get_name(list_entry));
393                 if (device_loop != NULL) {
394                         if (udev_device_get_devnum(device_loop) == devnum) {
395                                 if (type == 'b' && strcmp(udev_device_get_subsystem(device_loop), "block") != 0)
396                                         continue;
397                                 if (type == 'c' && strcmp(udev_device_get_subsystem(device_loop), "block") == 0)
398                                         continue;
399                                 device = device_loop;
400                                 break;
401                         }
402                         udev_device_unref(device_loop);
403                 }
404         }
405         udev_enumerate_unref(udev_enumerate);
406         return device;
407 }
408
409 struct udev_device *udev_device_new_from_subsystem_sysname(struct udev *udev, const char *subsystem, const char *sysname)
410 {
411         size_t sys_path_len;
412         char path_full[UTIL_PATH_SIZE];
413         char *path;
414         struct stat statbuf;
415
416         sys_path_len = util_strlcpy(path_full, udev_get_sys_path(udev), sizeof(path_full));
417         path = &path_full[sys_path_len];
418
419         if (strcmp(subsystem, "subsystem") == 0) {
420                 util_strlcpy(path, "/subsystem/", sizeof(path_full) - sys_path_len);
421                 util_strlcat(path, sysname, sizeof(path_full) - sys_path_len);
422                 if (stat(path_full, &statbuf) == 0)
423                         goto found;
424
425                 util_strlcpy(path, "/bus/", sizeof(path_full) - sys_path_len);
426                 util_strlcat(path, sysname, sizeof(path_full) - sys_path_len);
427                 if (stat(path_full, &statbuf) == 0)
428                         goto found;
429
430                 util_strlcpy(path, "/class/", sizeof(path_full) - sys_path_len);
431                 util_strlcat(path, sysname, sizeof(path_full) - sys_path_len);
432                 if (stat(path_full, &statbuf) == 0)
433                         goto found;
434                 goto out;
435         }
436
437         if (strcmp(subsystem, "module") == 0) {
438                 util_strlcpy(path, "/module/", sizeof(path_full) - sys_path_len);
439                 util_strlcat(path, sysname, sizeof(path_full) - sys_path_len);
440                 if (stat(path_full, &statbuf) == 0)
441                         goto found;
442                 goto out;
443         }
444
445         if (strcmp(subsystem, "drivers") == 0) {
446                 char subsys[UTIL_NAME_SIZE];
447                 char *driver;
448
449                 util_strlcpy(subsys, sysname, sizeof(subsys));
450                 driver = strchr(subsys, ':');
451                 if (driver != NULL) {
452                         driver[0] = '\0';
453                         driver = &driver[1];
454                         util_strlcpy(path, "/subsystem/", sizeof(path_full) - sys_path_len);
455                         util_strlcat(path, subsys, sizeof(path_full) - sys_path_len);
456                         util_strlcat(path, "/drivers/", sizeof(path_full) - sys_path_len);
457                         util_strlcat(path, driver, sizeof(path_full) - sys_path_len);
458                         if (stat(path_full, &statbuf) == 0)
459                                 goto found;
460
461                         util_strlcpy(path, "/bus/", sizeof(path_full) - sys_path_len);
462                         util_strlcat(path, subsys, sizeof(path_full) - sys_path_len);
463                         util_strlcat(path, "/drivers/", sizeof(path_full) - sys_path_len);
464                         util_strlcat(path, driver, sizeof(path_full) - sys_path_len);
465                         if (stat(path_full, &statbuf) == 0)
466                                 goto found;
467                 }
468                 goto out;
469         }
470
471         util_strlcpy(path, "/subsystem/", sizeof(path_full) - sys_path_len);
472         util_strlcat(path, subsystem, sizeof(path_full) - sys_path_len);
473         util_strlcat(path, "/devices/", sizeof(path_full) - sys_path_len);
474         util_strlcat(path, sysname, sizeof(path_full) - sys_path_len);
475         if (stat(path_full, &statbuf) == 0)
476                 goto found;
477
478         util_strlcpy(path, "/bus/", sizeof(path_full) - sys_path_len);
479         util_strlcat(path, subsystem, sizeof(path_full) - sys_path_len);
480         util_strlcat(path, "/devices/", sizeof(path_full) - sys_path_len);
481         util_strlcat(path, sysname, sizeof(path_full) - sys_path_len);
482         if (stat(path_full, &statbuf) == 0)
483                 goto found;
484
485         util_strlcpy(path, "/class/", sizeof(path_full) - sys_path_len);
486         util_strlcat(path, subsystem, sizeof(path_full) - sys_path_len);
487         util_strlcat(path, "/", sizeof(path_full) - sys_path_len);
488         util_strlcat(path, sysname, sizeof(path_full) - sys_path_len);
489         if (stat(path_full, &statbuf) == 0)
490                 goto found;
491 out:
492         return NULL;
493 found:
494         return udev_device_new_from_syspath(udev, path_full);
495 }
496
497 static struct udev_device *device_new_from_parent(struct udev_device *udev_device)
498 {
499         struct udev_device *udev_device_parent = NULL;
500         char path[UTIL_PATH_SIZE];
501         const char *subdir;
502
503         /* follow "device" link in deprecated sys layout */
504         if (strncmp(udev_device->devpath, "/class/", 7) == 0 ||
505             strncmp(udev_device->devpath, "/block/", 7) == 0) {
506                 util_strlcpy(path, udev_device->syspath, sizeof(path));
507                 util_strlcat(path, "/device", sizeof(path));
508                 if (util_resolve_sys_link(udev_device->udev, path, sizeof(path)) == 0) {
509                         udev_device_parent = udev_device_new_from_syspath(udev_device->udev, path);
510                         if (udev_device_parent != NULL)
511                                 return udev_device_parent;
512                 }
513         }
514
515         util_strlcpy(path, udev_device->syspath, sizeof(path));
516         subdir = &path[strlen(udev_get_sys_path(udev_device->udev))+1];
517         while (1) {
518                 char *pos;
519
520                 pos = strrchr(subdir, '/');
521                 if (pos == NULL || pos < &subdir[2])
522                         break;
523                 pos[0] = '\0';
524                 udev_device_parent = udev_device_new_from_syspath(udev_device->udev, path);
525                 if (udev_device_parent != NULL)
526                         return udev_device_parent;
527         }
528         return NULL;
529 }
530
531 struct udev_device *udev_device_get_parent(struct udev_device *udev_device)
532 {
533         if (udev_device == NULL)
534                 return NULL;
535         if (!udev_device->parent_set) {
536                 udev_device->parent_set = 1;
537                 udev_device->parent_device = device_new_from_parent(udev_device);
538         }
539         if (udev_device->parent_device != NULL)
540                 dbg(udev_device->udev, "returning existing parent %p\n", udev_device->parent_device);
541         return udev_device->parent_device;
542 }
543
544 struct udev_device *udev_device_get_parent_with_subsystem(struct udev_device *udev_device, const char *subsystem)
545 {
546         struct udev_device *parent;
547
548         parent = udev_device_get_parent(udev_device);
549         while (parent != NULL) {
550                 const char *parent_subsystem;
551
552                 parent_subsystem = udev_device_get_subsystem(parent);
553                 if (parent_subsystem != NULL && strcmp(parent_subsystem, subsystem) == 0)
554                         break;
555                 parent = udev_device_get_parent(parent);
556         }
557         return parent;
558 }
559
560 struct udev_device *udev_device_get_parent_with_devtype(struct udev_device *udev_device, const char *devtype)
561 {
562         struct udev_device *parent;
563
564         parent = udev_device_get_parent(udev_device);
565         while (parent != NULL) {
566                 const char *parent_devtype;
567
568                 parent_devtype = udev_device_get_devtype(parent);
569                 if (parent_devtype != NULL && strcmp(parent_devtype, devtype) == 0)
570                         break;
571                 parent = udev_device_get_parent(parent);
572         }
573         return parent;
574 }
575
576 /**
577  * udev_device_get_udev:
578  * @udev_device: udev device
579  *
580  * Retrieve the udev library context the device was created with.
581  *
582  * Returns: the udev library context
583  **/
584 struct udev *udev_device_get_udev(struct udev_device *udev_device)
585 {
586         if (udev_device == NULL)
587                 return NULL;
588         return udev_device->udev;
589 }
590
591 /**
592  * udev_device_ref:
593  * @udev_device: udev device
594  *
595  * Take a reference of a udev device.
596  *
597  * Returns: the passed udev device
598  **/
599 struct udev_device *udev_device_ref(struct udev_device *udev_device)
600 {
601         if (udev_device == NULL)
602                 return NULL;
603         udev_device->refcount++;
604         return udev_device;
605 }
606
607 /**
608  * udev_device_unref:
609  * @udev_device: udev device
610  *
611  * Drop a reference of a udev device. If the refcount reaches zero,
612  * the resources of the device will be released.
613  *
614  **/
615 void udev_device_unref(struct udev_device *udev_device)
616 {
617         if (udev_device == NULL)
618                 return;
619         udev_device->refcount--;
620         if (udev_device->refcount > 0)
621                 return;
622         if (udev_device->parent_device != NULL)
623                 udev_device_unref(udev_device->parent_device);
624         free(udev_device->syspath);
625         free(udev_device->sysname);
626         free(udev_device->devnode);
627         free(udev_device->subsystem);
628         free(udev_device->devtype);
629         udev_list_cleanup_entries(udev_device->udev, &udev_device->devlinks_list);
630         udev_list_cleanup_entries(udev_device->udev, &udev_device->properties_list);
631         free(udev_device->action);
632         free(udev_device->driver);
633         free(udev_device->devpath_old);
634         free(udev_device->physdevpath);
635         udev_list_cleanup_entries(udev_device->udev, &udev_device->sysattr_list);
636         free(udev_device->envp);
637         free(udev_device->monitor_buf);
638         dbg(udev_device->udev, "udev_device: %p released\n", udev_device);
639         free(udev_device);
640 }
641
642 /**
643  * udev_device_get_devpath:
644  * @udev_device: udev device
645  *
646  * Retrieve the kernel devpath value of the udev device. The path
647  * does not contain the sys mount point, and starts with a '/'.
648  *
649  * Returns: the devpath of the udev device
650  **/
651 const char *udev_device_get_devpath(struct udev_device *udev_device)
652 {
653         if (udev_device == NULL)
654                 return NULL;
655         return udev_device->devpath;
656 }
657
658 /**
659  * udev_device_get_syspath:
660  * @udev_device: udev device
661  *
662  * Retrieve the sys path of the udev device. The path is an
663  * absolute path and starts with the sys mount point.
664  *
665  * Returns: the sys path of the udev device
666  **/
667 const char *udev_device_get_syspath(struct udev_device *udev_device)
668 {
669         if (udev_device == NULL)
670                 return NULL;
671         return udev_device->syspath;
672 }
673
674 const char *udev_device_get_sysname(struct udev_device *udev_device)
675 {
676         if (udev_device == NULL)
677                 return NULL;
678         return udev_device->sysname;
679 }
680
681 const char *udev_device_get_sysnum(struct udev_device *udev_device)
682 {
683         if (udev_device == NULL)
684                 return NULL;
685         return udev_device->sysnum;
686 }
687
688 /**
689  * udev_device_get_devnode:
690  * @udev_device: udev device
691  *
692  * Retrieve the device node file name belonging to the udev device.
693  * The path is an absolute path, and starts with the device directory.
694  *
695  * Returns: the device node file name of the udev device, or #NULL if no device node exists
696  **/
697 const char *udev_device_get_devnode(struct udev_device *udev_device)
698 {
699         if (udev_device == NULL)
700                 return NULL;
701         if (!udev_device->info_loaded)
702                 device_load_info(udev_device);
703         return udev_device->devnode;
704 }
705
706 /**
707  * udev_device_get_subsystem:
708  * @udev_device: udev device
709  *
710  * Retrieve the subsystem string of the udev device. The string does not
711  * contain any "/".
712  *
713  * Returns: the subsystem name of the udev device, or #NULL if it can not be determined
714  **/
715 const char *udev_device_get_subsystem(struct udev_device *udev_device)
716 {
717         char subsystem[UTIL_NAME_SIZE];
718
719         if (udev_device == NULL)
720                 return NULL;
721         if (!udev_device->subsystem_set) {
722                 udev_device->subsystem_set = 1;
723                 /* read "subsytem" link */
724                 if (util_get_sys_subsystem(udev_device->udev, udev_device->syspath, subsystem, sizeof(subsystem)) > 0) {
725                         udev_device_set_subsystem(udev_device, subsystem);
726                         return udev_device->subsystem;
727                 }
728                 /* implicit names */
729                 if (strncmp(udev_device->devpath, "/module/", 8) == 0) {
730                         udev_device_set_subsystem(udev_device, "module");
731                         return udev_device->subsystem;
732                 }
733                 if (strstr(udev_device->devpath, "/drivers/") != NULL) {
734                         udev_device_set_subsystem(udev_device, "drivers");
735                         return udev_device->subsystem;
736                 }
737                 if (strncmp(udev_device->devpath, "/subsystem/", 11) == 0 ||
738                     strncmp(udev_device->devpath, "/class/", 7) == 0 ||
739                     strncmp(udev_device->devpath, "/bus/", 5) == 0) {
740                         udev_device_set_subsystem(udev_device, "subsystem");
741                         return udev_device->subsystem;
742                 }
743         }
744         return udev_device->subsystem;
745 }
746
747 /**
748  * udev_device_get_devtype:
749  * @udev_device: udev device
750  *
751  * Retrieve the devtype string of the udev device.
752  *
753  * Returns: the devtype name of the udev device, or #NULL if it can not be determined
754  **/
755 const char *udev_device_get_devtype(struct udev_device *udev_device)
756 {
757         if (udev_device == NULL)
758                 return NULL;
759         if (!udev_device->devtype_set) {
760                 udev_device->devtype_set = 1;
761                 udev_device_read_uevent_file(udev_device);
762         }
763         return udev_device->devtype;
764 }
765
766 /**
767  * udev_device_get_devlinks_list_entry:
768  * @udev_device: udev device
769  *
770  * Retrieve the list of device links pointing to the device file of
771  * the udev device. The next list entry can be retrieved with
772  * udev_list_entry_next(), which returns #NULL if no more entries exist.
773  * The devlink path can be retrieved from the list entry by
774  * udev_list_entry_get_name(). The path is an absolute path, and starts with
775  * the device directory.
776  *
777  * Returns: the first entry of the device node link list
778  **/
779 struct udev_list_entry *udev_device_get_devlinks_list_entry(struct udev_device *udev_device)
780 {
781         if (udev_device == NULL)
782                 return NULL;
783         if (!udev_device->info_loaded)
784                 device_load_info(udev_device);
785         return udev_list_get_entry(&udev_device->devlinks_list);
786 }
787
788 void udev_device_cleanup_devlinks_list(struct udev_device *udev_device)
789 {
790         udev_device->devlinks_uptodate = 0;
791         udev_list_cleanup_entries(udev_device->udev, &udev_device->devlinks_list);
792 }
793
794 /**
795  * udev_device_get_properties_list_entry:
796  * @udev_device: udev device
797  *
798  * Retrieve the list of key/value device properties of the udev
799  * device. The next list entry can be retrieved with udev_list_entry_next(),
800  * which returns #NULL if no more entries exist. The property name
801  * can be retrieved from the list entry by udev_list_get_name(),
802  * the property value by udev_list_get_value().
803  *
804  * Returns: the first entry of the property list
805  **/
806 struct udev_list_entry *udev_device_get_properties_list_entry(struct udev_device *udev_device)
807 {
808         if (udev_device == NULL)
809                 return NULL;
810         if (!udev_device->info_loaded)
811                 device_load_info(udev_device);
812         if (!udev_device->devlinks_uptodate) {
813                 char symlinks[UTIL_PATH_SIZE];
814                 struct udev_list_entry *list_entry;
815
816                 udev_device->devlinks_uptodate = 1;
817                 list_entry = udev_device_get_devlinks_list_entry(udev_device);
818                 if (list_entry != NULL) {
819                         util_strlcpy(symlinks, udev_list_entry_get_name(list_entry), sizeof(symlinks));
820                         udev_list_entry_foreach(list_entry, udev_list_entry_get_next(list_entry)) {
821                                 util_strlcat(symlinks, " ", sizeof(symlinks));
822                                 util_strlcat(symlinks, udev_list_entry_get_name(list_entry), sizeof(symlinks));
823                         }
824                         udev_device_add_property(udev_device, "DEVLINKS", symlinks);
825                 }
826         }
827         return udev_list_get_entry(&udev_device->properties_list);
828 }
829
830 const char *udev_device_get_driver(struct udev_device *udev_device)
831 {
832         char driver[UTIL_NAME_SIZE];
833
834         if (udev_device == NULL)
835                 return NULL;
836         if (!udev_device->driver_set) {
837                 udev_device->driver_set = 1;
838                 if (util_get_sys_driver(udev_device->udev, udev_device->syspath, driver, sizeof(driver)) > 0)
839                         udev_device->driver = strdup(driver);
840         }
841         return udev_device->driver;
842 }
843
844 dev_t udev_device_get_devnum(struct udev_device *udev_device)
845 {
846         if (udev_device == NULL)
847                 return makedev(0, 0);
848         if (!udev_device->info_loaded)
849                 device_load_info(udev_device);
850         return udev_device->devnum;
851 }
852
853 const char *udev_device_get_action(struct udev_device *udev_device)
854 {
855         if (udev_device == NULL)
856                 return NULL;
857         return udev_device->action;
858 }
859
860 unsigned long long int udev_device_get_seqnum(struct udev_device *udev_device)
861 {
862         if (udev_device == NULL)
863                 return 0;
864         return udev_device->seqnum;
865 }
866
867 const char *udev_device_get_sysattr_value(struct udev_device *udev_device, const char *sysattr)
868 {
869         struct udev_list_entry *list_entry;
870         char path[UTIL_PATH_SIZE];
871         char value[UTIL_NAME_SIZE];
872         struct stat statbuf;
873         int fd;
874         ssize_t size;
875         const char *val = NULL;
876
877         if (udev_device == NULL)
878                 return NULL;
879         if (sysattr == NULL)
880                 return NULL;
881
882         /* look for possibly already cached result */
883         udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_device->sysattr_list)) {
884                 if (strcmp(udev_list_entry_get_name(list_entry), sysattr) == 0) {
885                         dbg(udev_device->udev, "got '%s' (%s) from cache\n",
886                             sysattr, udev_list_entry_get_value(list_entry));
887                         return udev_list_entry_get_value(list_entry);
888                 }
889         }
890
891         util_strlcpy(path, udev_device_get_syspath(udev_device), sizeof(path));
892         util_strlcat(path, "/", sizeof(path));
893         util_strlcat(path, sysattr, sizeof(path));
894
895         if (lstat(path, &statbuf) != 0) {
896                 dbg(udev_device->udev, "no attribute '%s', keep negative entry\n", path);
897                 udev_list_entry_add(udev_device->udev, &udev_device->sysattr_list, sysattr, NULL, 0, 0);
898                 goto out;
899         }
900
901         if (S_ISLNK(statbuf.st_mode)) {
902                 char target[UTIL_NAME_SIZE];
903                 int len;
904                 char *pos;
905
906                 /* some core links return the last element of the target path */
907                 if (strcmp(sysattr, "driver") != 0 &&
908                     strcmp(sysattr, "subsystem") != 0 &&
909                     strcmp(sysattr, "module") != 0)
910                         goto out;
911
912                 len = readlink(path, target, sizeof(target));
913                 if (len > 0) {
914                         target[len] = '\0';
915                         pos = strrchr(target, '/');
916                         if (pos != NULL) {
917                                 pos = &pos[1];
918                                 dbg(udev_device->udev, "cache '%s' with link value '%s'\n", sysattr, pos);
919                                 list_entry = udev_list_entry_add(udev_device->udev, &udev_device->sysattr_list, sysattr, pos, 0, 0);
920                                 val = udev_list_entry_get_value(list_entry);
921                         }
922                 }
923                 goto out;
924         }
925
926         /* skip directories */
927         if (S_ISDIR(statbuf.st_mode))
928                 goto out;
929
930         /* skip non-readable files */
931         if ((statbuf.st_mode & S_IRUSR) == 0)
932                 goto out;
933
934         /* read attribute value */
935         fd = open(path, O_RDONLY);
936         if (fd < 0) {
937                 dbg(udev_device->udev, "attribute '%s' can not be opened\n", path);
938                 goto out;
939         }
940         size = read(fd, value, sizeof(value));
941         close(fd);
942         if (size < 0)
943                 goto out;
944         if (size == sizeof(value))
945                 goto out;
946
947         /* got a valid value, store it in cache and return it */
948         value[size] = '\0';
949         util_remove_trailing_chars(value, '\n');
950         dbg(udev_device->udev, "'%s' has attribute value '%s'\n", path, value);
951         list_entry = udev_list_entry_add(udev_device->udev, &udev_device->sysattr_list, sysattr, value, 0, 0);
952         val = udev_list_entry_get_value(list_entry);
953 out:
954         return val;
955 }
956
957 int udev_device_set_syspath(struct udev_device *udev_device, const char *syspath)
958 {
959         const char *pos;
960         size_t len;
961
962         free(udev_device->syspath);
963         udev_device->syspath = strdup(syspath);
964         if (udev_device->syspath ==  NULL)
965                 return -ENOMEM;
966         udev_device->devpath = &udev_device->syspath[strlen(udev_get_sys_path(udev_device->udev))];
967         udev_device_add_property(udev_device, "DEVPATH", udev_device->devpath);
968
969         pos = strrchr(udev_device->syspath, '/');
970         if (pos == NULL)
971                 return -EINVAL;
972         udev_device->sysname = strdup(&pos[1]);
973         if (udev_device->sysname == NULL)
974                 return -ENOMEM;
975
976         /* some devices have '!' in their name, change that to '/' */
977         len = 0;
978         while (udev_device->sysname[len] != '\0') {
979                 if (udev_device->sysname[len] == '!')
980                         udev_device->sysname[len] = '/';
981                 len++;
982         }
983
984         /* trailing number */
985         while (len > 0 && isdigit(udev_device->sysname[--len]))
986                 udev_device->sysnum = &udev_device->sysname[len];
987
988         /* sysname is completely numeric */
989         if (len == 0)
990                 udev_device->sysnum = NULL;
991
992         return 0;
993 }
994
995 int udev_device_set_subsystem(struct udev_device *udev_device, const char *subsystem)
996 {
997         free(udev_device->subsystem);
998         udev_device->subsystem = strdup(subsystem);
999         if (udev_device->subsystem == NULL)
1000                 return -ENOMEM;
1001         udev_device->subsystem_set = 1;
1002         udev_device_add_property(udev_device, "SUBSYSTEM", udev_device->subsystem);
1003         return 0;
1004 }
1005
1006 int udev_device_set_devtype(struct udev_device *udev_device, const char *devtype)
1007 {
1008         free(udev_device->devtype);
1009         udev_device->devtype = strdup(devtype);
1010         if (udev_device->devtype == NULL)
1011                 return -ENOMEM;
1012         udev_device->devtype_set = 1;
1013         udev_device_add_property(udev_device, "DEVTYPE", udev_device->devtype);
1014         return 0;
1015 }
1016
1017 int udev_device_set_devnode(struct udev_device *udev_device, const char *devnode)
1018 {
1019         free(udev_device->devnode);
1020         udev_device->devnode = strdup(devnode);
1021         if (devnode == NULL)
1022                 return 0;
1023         if (udev_device->devnode == NULL)
1024                 return -ENOMEM;
1025         udev_device_add_property(udev_device, "DEVNAME", udev_device->devnode);
1026         return 0;
1027 }
1028
1029 int udev_device_add_devlink(struct udev_device *udev_device, const char *devlink)
1030 {
1031         udev_device->devlinks_uptodate = 0;
1032         if (udev_list_entry_add(udev_device->udev, &udev_device->devlinks_list, devlink, NULL, 1, 0) == NULL)
1033                 return -ENOMEM;
1034         return 0;
1035 }
1036
1037 struct udev_list_entry *udev_device_add_property(struct udev_device *udev_device, const char *key, const char *value)
1038 {
1039         udev_device->envp_uptodate = 0;
1040         if (value == NULL) {
1041                 struct udev_list_entry *list_entry;
1042
1043                 list_entry = udev_device_get_properties_list_entry(udev_device);
1044                 list_entry = udev_list_entry_get_by_name(list_entry, key);
1045                 if (list_entry != NULL)
1046                         udev_list_entry_delete(list_entry);
1047                 return NULL;
1048         }
1049         return udev_list_entry_add(udev_device->udev, &udev_device->properties_list, key, value, 1, 0);
1050 }
1051
1052 struct udev_list_entry *udev_device_add_property_from_string(struct udev_device *udev_device, const char *property)
1053 {
1054         char name[UTIL_PATH_SIZE];
1055         char *val;
1056
1057         util_strlcpy(name, property, sizeof(name));
1058         val = strchr(name, '=');
1059         if (val == NULL)
1060                 return NULL;
1061         val[0] = '\0';
1062         val = &val[1];
1063         if (val[0] == '\0')
1064                 val = NULL;
1065         return udev_device_add_property(udev_device, name, val);
1066 }
1067
1068 #define ENVP_SIZE                       128
1069 #define MONITOR_BUF_SIZE                4096
1070 static int update_envp_monitor_buf(struct udev_device *udev_device)
1071 {
1072         const char *action;
1073         struct udev_list_entry *list_entry;
1074         size_t bufpos;
1075         size_t len;
1076         unsigned int i;
1077
1078         /* monitor buffer of property strings */
1079         free(udev_device->monitor_buf);
1080         udev_device->monitor_buf_len = 0;
1081         udev_device->monitor_buf = malloc(MONITOR_BUF_SIZE);
1082         if (udev_device->monitor_buf == NULL)
1083                 return -ENOMEM;
1084
1085         /* envp array, strings will point into monitor buffer */
1086         if (udev_device->envp == NULL)
1087                 udev_device->envp = malloc(sizeof(char *) * ENVP_SIZE);
1088         if (udev_device->envp == NULL)
1089                 return -ENOMEM;
1090
1091         /* header <action>@<devpath> */
1092         action = udev_device_get_action(udev_device);
1093         if (action == NULL)
1094                 return -EINVAL;
1095         bufpos = util_strlcpy(udev_device->monitor_buf, action, MONITOR_BUF_SIZE);
1096         len = util_strlcpy(&udev_device->monitor_buf[bufpos], "@", MONITOR_BUF_SIZE-bufpos);
1097         if (len >= MONITOR_BUF_SIZE-bufpos)
1098                 return -EINVAL;
1099         bufpos += len;
1100         len = util_strlcpy(&udev_device->monitor_buf[bufpos],
1101                            udev_device_get_devpath(udev_device),
1102                            MONITOR_BUF_SIZE-bufpos);
1103         if (len+1 >= MONITOR_BUF_SIZE-bufpos)
1104                 return -EINVAL;
1105         bufpos += len+1;
1106
1107         i = 0;
1108         udev_list_entry_foreach(list_entry, udev_device_get_properties_list_entry(udev_device)) {
1109                 /* add string to envp array */
1110                 udev_device->envp[i++] = &udev_device->monitor_buf[bufpos];
1111                 if (i+1 >= ENVP_SIZE)
1112                         return -EINVAL;
1113
1114                 /* add property string to monitor buffer */
1115                 len = util_strlcpy(&udev_device->monitor_buf[bufpos],
1116                                    udev_list_entry_get_name(list_entry), MONITOR_BUF_SIZE-bufpos);
1117                 if (len >= MONITOR_BUF_SIZE-bufpos)
1118                         return -EINVAL;
1119                 bufpos += len;
1120                 len = util_strlcpy(&udev_device->monitor_buf[bufpos], "=", MONITOR_BUF_SIZE-bufpos);
1121                 if (len >= MONITOR_BUF_SIZE-bufpos)
1122                         return -EINVAL;
1123                 bufpos += len;
1124                 len = util_strlcpy(&udev_device->monitor_buf[bufpos], udev_list_entry_get_value(list_entry),
1125                                    MONITOR_BUF_SIZE-bufpos);
1126                 if (len+1 >= MONITOR_BUF_SIZE-bufpos)
1127                         return -EINVAL;
1128                 bufpos += len+1;
1129         }
1130         udev_device->envp[i] = NULL;
1131         udev_device->monitor_buf_len = bufpos;
1132         udev_device->envp_uptodate = 1;
1133         dbg(udev_device->udev, "filled envp/monitor buffer, %u properties, %zu bytes\n", i, bufpos);
1134         return 0;
1135 }
1136
1137 char **udev_device_get_properties_envp(struct udev_device *udev_device)
1138 {
1139         if (!udev_device->envp_uptodate)
1140                 if (update_envp_monitor_buf(udev_device) != 0)
1141                         return NULL;
1142         return udev_device->envp;
1143 }
1144
1145 ssize_t udev_device_get_properties_monitor_buf(struct udev_device *udev_device, const char **buf)
1146 {
1147         if (!udev_device->envp_uptodate)
1148                 if (update_envp_monitor_buf(udev_device) != 0)
1149                         return -EINVAL;
1150         *buf = udev_device->monitor_buf;
1151         return udev_device->monitor_buf_len;
1152 }
1153
1154 int udev_device_set_action(struct udev_device *udev_device, const char *action)
1155 {
1156         free(udev_device->action);
1157         udev_device->action = strdup(action);
1158         if (udev_device->action == NULL)
1159                 return -ENOMEM;
1160         udev_device_add_property(udev_device, "ACTION", udev_device->action);
1161         return 0;
1162 }
1163
1164 int udev_device_set_driver(struct udev_device *udev_device, const char *driver)
1165 {
1166         free(udev_device->driver);
1167         udev_device->driver = strdup(driver);
1168         if (udev_device->driver == NULL)
1169                 return -ENOMEM;
1170         udev_device->driver_set = 1;
1171         udev_device_add_property(udev_device, "DRIVER", udev_device->driver);
1172         return 0;
1173 }
1174
1175 const char *udev_device_get_devpath_old(struct udev_device *udev_device)
1176 {
1177         return udev_device->devpath_old;
1178 }
1179
1180 int udev_device_set_devpath_old(struct udev_device *udev_device, const char *devpath_old)
1181 {
1182         udev_device->devpath_old = strdup(devpath_old);
1183         if (udev_device->devpath_old == NULL)
1184                 return -ENOMEM;
1185         udev_device_add_property(udev_device, "DEVPATH_OLD", udev_device->devpath_old);
1186         return 0;
1187 }
1188
1189 const char *udev_device_get_physdevpath(struct udev_device *udev_device)
1190 {
1191         return udev_device->physdevpath;
1192 }
1193
1194 int udev_device_set_physdevpath(struct udev_device *udev_device, const char *physdevpath)
1195 {
1196         udev_device->physdevpath = strdup(physdevpath);
1197         if (udev_device->physdevpath == NULL)
1198                 return -ENOMEM;
1199         return 0;
1200 }
1201
1202 int udev_device_get_timeout(struct udev_device *udev_device)
1203 {
1204         return udev_device->timeout;
1205 }
1206
1207 int udev_device_set_timeout(struct udev_device *udev_device, int timeout)
1208 {
1209         udev_device->timeout = timeout;
1210         return 0;
1211 }
1212 int udev_device_get_event_timeout(struct udev_device *udev_device)
1213 {
1214         if (!udev_device->info_loaded)
1215                 device_load_info(udev_device);
1216         return udev_device->event_timeout;
1217 }
1218
1219 int udev_device_set_event_timeout(struct udev_device *udev_device, int event_timeout)
1220 {
1221         udev_device->event_timeout = event_timeout;
1222         return 0;
1223 }
1224
1225 int udev_device_set_seqnum(struct udev_device *udev_device, unsigned long long int seqnum)
1226 {
1227         char num[32];
1228
1229         udev_device->seqnum = seqnum;
1230         snprintf(num, sizeof(num), "%llu", seqnum);
1231         udev_device_add_property(udev_device, "SEQNUM", num);
1232         return 0;
1233 }
1234
1235 int udev_device_set_devnum(struct udev_device *udev_device, dev_t devnum)
1236 {
1237         char num[32];
1238
1239         udev_device->devnum = devnum;
1240
1241         snprintf(num, sizeof(num), "%u", major(devnum));
1242         udev_device_add_property(udev_device, "MAJOR", num);
1243         snprintf(num, sizeof(num), "%u", minor(devnum));
1244         udev_device_add_property(udev_device, "MINOR", num);
1245         return 0;
1246 }
1247
1248 int udev_device_get_num_fake_partitions(struct udev_device *udev_device)
1249 {
1250         if (!udev_device->info_loaded)
1251                 device_load_info(udev_device);
1252         return udev_device->num_fake_partitions;
1253 }
1254
1255 int udev_device_set_num_fake_partitions(struct udev_device *udev_device, int num)
1256 {
1257         udev_device->num_fake_partitions = num;
1258         return 0;
1259 }
1260
1261 int udev_device_get_devlink_priority(struct udev_device *udev_device)
1262 {
1263         if (!udev_device->info_loaded)
1264                 device_load_info(udev_device);
1265         return udev_device->devlink_priority;
1266 }
1267
1268 int udev_device_set_devlink_priority(struct udev_device *udev_device, int prio)
1269 {
1270          udev_device->devlink_priority = prio;
1271         return 0;
1272 }
1273
1274 int udev_device_get_ignore_remove(struct udev_device *udev_device)
1275 {
1276         if (!udev_device->info_loaded)
1277                 device_load_info(udev_device);
1278         return udev_device->ignore_remove;
1279 }
1280
1281 int udev_device_set_ignore_remove(struct udev_device *udev_device, int ignore)
1282 {
1283         udev_device->ignore_remove = ignore;
1284         return 0;
1285 }