2 * libudev - interface to udev device information
4 * Copyright (C) 2008 Kay Sievers <kay.sievers@vrfy.org>
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
23 #include "libudev-private.h"
25 static int devices_sort(struct udev_enumerate *udev_enumerate);
28 * SECTION:libudev-enumerate
29 * @short_description: lookup and sort sys devices
31 * Lookup devices in the sys filesystem, filter devices by properties,
32 * and return a sorted list of devices.
38 * Opaque object representing one device lookup/sort context.
40 struct udev_enumerate {
43 struct udev_list_node sysattr_match_list;
44 struct udev_list_node sysattr_nomatch_list;
45 struct udev_list_node subsystem_match_list;
46 struct udev_list_node subsystem_nomatch_list;
47 struct udev_list_node properties_match_list;
48 struct udev_list_node devices_list;
54 * @udev: udev library context
56 * Returns: an enumeration context
58 struct udev_enumerate *udev_enumerate_new(struct udev *udev)
60 struct udev_enumerate *udev_enumerate;
62 udev_enumerate = calloc(1, sizeof(struct udev_enumerate));
63 if (udev_enumerate == NULL)
65 udev_enumerate->refcount = 1;
66 udev_enumerate->udev = udev;
67 udev_list_init(&udev_enumerate->devices_list);
68 udev_list_init(&udev_enumerate->sysattr_match_list);
69 udev_list_init(&udev_enumerate->sysattr_nomatch_list);
70 udev_list_init(&udev_enumerate->subsystem_match_list);
71 udev_list_init(&udev_enumerate->subsystem_nomatch_list);
72 udev_list_init(&udev_enumerate->properties_match_list);
73 return udev_enumerate;
78 * @udev_enumerate: context
80 * Take a reference of a enumeration context.
82 * Returns: the passed enumeration context
84 struct udev_enumerate *udev_enumerate_ref(struct udev_enumerate *udev_enumerate)
86 if (udev_enumerate == NULL)
88 udev_enumerate->refcount++;
89 return udev_enumerate;
93 * udev_enumerate_unref:
94 * @udev_enumerate: context
96 * Drop a reference of an enumeration context. If the refcount reaches zero,
97 * all resources of the enumeration context will be released.
99 void udev_enumerate_unref(struct udev_enumerate *udev_enumerate)
101 if (udev_enumerate == NULL)
103 udev_enumerate->refcount--;
104 if (udev_enumerate->refcount > 0)
106 udev_list_cleanup_entries(udev_enumerate->udev, &udev_enumerate->devices_list);
107 udev_list_cleanup_entries(udev_enumerate->udev, &udev_enumerate->sysattr_match_list);
108 udev_list_cleanup_entries(udev_enumerate->udev, &udev_enumerate->sysattr_nomatch_list);
109 udev_list_cleanup_entries(udev_enumerate->udev, &udev_enumerate->subsystem_match_list);
110 udev_list_cleanup_entries(udev_enumerate->udev, &udev_enumerate->subsystem_nomatch_list);
111 udev_list_cleanup_entries(udev_enumerate->udev, &udev_enumerate->properties_match_list);
112 free(udev_enumerate);
116 * udev_enumerate_get_udev:
117 * @udev_enumerate: context
119 * Returns: the udev library context.
121 struct udev *udev_enumerate_get_udev(struct udev_enumerate *udev_enumerate)
123 if (udev_enumerate == NULL)
125 return udev_enumerate->udev;
129 * udev_enumerate_get_list_entry:
130 * @udev_enumerate: context
132 * Returns: the first entry of the sorted list of device paths.
134 struct udev_list_entry *udev_enumerate_get_list_entry(struct udev_enumerate *udev_enumerate)
136 if (udev_enumerate == NULL)
138 if (!udev_enumerate->devices_sorted)
139 devices_sort(udev_enumerate);
140 return udev_list_get_entry(&udev_enumerate->devices_list);
144 * udev_enumerate_add_match_subsystem:
145 * @udev_enumerate: context
146 * @subsystem: filter for a subsystem of the device to include in the list
148 * Returns: 0 on success, otherwise a negative error value.
150 int udev_enumerate_add_match_subsystem(struct udev_enumerate *udev_enumerate, const char *subsystem)
152 if (udev_enumerate == NULL)
154 if (subsystem == NULL)
156 if (udev_list_entry_add(udev_enumerate_get_udev(udev_enumerate),
157 &udev_enumerate->subsystem_match_list, subsystem, NULL, 1, 0) == NULL)
163 * udev_enumerate_add_nomatch_subsystem:
164 * @udev_enumerate: context
165 * @subsystem: filter for a subsystem of the device to exclude from the list
167 * Returns: 0 on success, otherwise a negative error value.
169 int udev_enumerate_add_nomatch_subsystem(struct udev_enumerate *udev_enumerate, const char *subsystem)
171 if (udev_enumerate == NULL)
173 if (subsystem == NULL)
175 if (udev_list_entry_add(udev_enumerate_get_udev(udev_enumerate),
176 &udev_enumerate->subsystem_nomatch_list, subsystem, NULL, 1, 0) == NULL)
182 * udev_enumerate_add_match_sysattr:
183 * @udev_enumerate: context
184 * @sysattr: filter for a sys attribute at the device to include in the list
185 * @value: optional value of the sys attribute
187 * Returns: 0 on success, otherwise a negative error value.
189 int udev_enumerate_add_match_sysattr(struct udev_enumerate *udev_enumerate, const char *sysattr, const char *value)
191 if (udev_enumerate == NULL)
195 if (udev_list_entry_add(udev_enumerate_get_udev(udev_enumerate),
196 &udev_enumerate->sysattr_match_list, sysattr, value, 0, 0) == NULL)
202 * udev_enumerate_add_nomatch_sysattr:
203 * @udev_enumerate: context
204 * @sysattr: filter for a sys attribute at the device to exclude from the list
205 * @value: optional value of the sys attribute
207 * Returns: 0 on success, otherwise a negative error value.
209 int udev_enumerate_add_nomatch_sysattr(struct udev_enumerate *udev_enumerate, const char *sysattr, const char *value)
211 if (udev_enumerate == NULL)
215 if (udev_list_entry_add(udev_enumerate_get_udev(udev_enumerate),
216 &udev_enumerate->sysattr_nomatch_list, sysattr, value, 0, 0) == NULL)
221 static int match_sysattr_value(struct udev *udev, const char *syspath, const char *sysattr, const char *match_val)
223 struct udev_device *device;
224 const char *val = NULL;
227 device = udev_device_new_from_syspath(udev, syspath);
230 val = udev_device_get_sysattr_value(device, sysattr);
233 if (match_val == NULL) {
237 if (fnmatch(match_val, val, 0) == 0) {
242 udev_device_unref(device);
247 * udev_enumerate_add_match_property:
248 * @udev_enumerate: context
249 * @property: filter for a property of the device to include in the list
250 * @value: value of the property
252 * Returns: 0 on success, otherwise a negative error value.
254 int udev_enumerate_add_match_property(struct udev_enumerate *udev_enumerate, const char *property, const char *value)
256 if (udev_enumerate == NULL)
258 if (property == NULL)
260 if (udev_list_entry_add(udev_enumerate_get_udev(udev_enumerate),
261 &udev_enumerate->properties_match_list, property, value, 0, 0) == NULL)
266 static int match_sysattr(struct udev_enumerate *udev_enumerate, const char *syspath)
268 struct udev *udev = udev_enumerate_get_udev(udev_enumerate);
269 struct udev_list_entry *list_entry;
272 udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_enumerate->sysattr_nomatch_list)) {
273 if (match_sysattr_value(udev, syspath,
274 udev_list_entry_get_name(list_entry),
275 udev_list_entry_get_value(list_entry)))
279 if (udev_list_get_entry(&udev_enumerate->sysattr_match_list) != NULL) {
280 udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_enumerate->sysattr_match_list)) {
281 /* anything that does not match, will make it FALSE */
282 if (!match_sysattr_value(udev, syspath,
283 udev_list_entry_get_name(list_entry),
284 udev_list_entry_get_value(list_entry)))
292 static int match_property(struct udev_enumerate *udev_enumerate, const char *syspath)
294 struct udev_device *dev;
295 struct udev_list_entry *list_entry;
298 /* no match always matches */
299 if (udev_list_get_entry(&udev_enumerate->properties_match_list) == NULL)
302 /* no device does not match */
303 dev = udev_device_new_from_syspath(udev_enumerate->udev, syspath);
307 /* loop over matches */
308 udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_enumerate->properties_match_list)) {
309 const char *match_key = udev_list_entry_get_name(list_entry);
310 const char *match_value = udev_list_entry_get_value(list_entry);
311 struct udev_list_entry *property_entry;
313 /* loop over device properties */
314 udev_list_entry_foreach(property_entry, udev_device_get_properties_list_entry(dev)) {
315 const char *dev_key = udev_list_entry_get_name(property_entry);
316 const char *dev_value = udev_list_entry_get_value(property_entry);
318 if (fnmatch(match_key, dev_key, 0) != 0)
320 if (match_value == NULL && dev_value == NULL) {
324 if (match_value == NULL || dev_value == NULL)
326 if (fnmatch(match_value, dev_value, 0) == 0) {
333 udev_device_unref(dev);
337 static int scan_dir_and_add_devices(struct udev_enumerate *udev_enumerate,
338 const char *basedir, const char *subdir1, const char *subdir2)
340 struct udev *udev = udev_enumerate_get_udev(udev_enumerate);
341 char path[UTIL_PATH_SIZE];
348 l = util_strpcpyl(&s, sizeof(path), udev_get_sys_path(udev), "/", basedir, NULL);
350 l = util_strpcpyl(&s, l, "/", subdir1, NULL);
352 l = util_strpcpyl(&s, l, "/", subdir2, NULL);
356 for (dent = readdir(dir); dent != NULL; dent = readdir(dir)) {
357 char syspath[UTIL_PATH_SIZE];
358 char filename[UTIL_PATH_SIZE];
361 if (dent->d_name[0] == '.')
363 util_strscpyl(syspath, sizeof(syspath), path, "/", dent->d_name, NULL);
364 if (lstat(syspath, &statbuf) != 0)
366 if (S_ISREG(statbuf.st_mode))
368 if (S_ISLNK(statbuf.st_mode))
369 util_resolve_sys_link(udev, syspath, sizeof(syspath));
371 util_strscpyl(filename, sizeof(filename), syspath, "/uevent", NULL);
372 if (stat(filename, &statbuf) != 0)
374 if (!match_sysattr(udev_enumerate, syspath))
376 if (!match_property(udev_enumerate, syspath))
378 udev_list_entry_add(udev, &udev_enumerate->devices_list, syspath, NULL, 1, 1);
384 static int match_subsystem(struct udev_enumerate *udev_enumerate, const char *subsystem)
386 struct udev_list_entry *list_entry;
388 udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_enumerate->subsystem_nomatch_list)) {
389 if (fnmatch(udev_list_entry_get_name(list_entry), subsystem, 0) == 0)
392 if (udev_list_get_entry(&udev_enumerate->subsystem_match_list) != NULL) {
393 udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_enumerate->subsystem_match_list)) {
394 if (fnmatch(udev_list_entry_get_name(list_entry), subsystem, 0) == 0)
402 static int scan_dir(struct udev_enumerate *udev_enumerate, const char *basedir, const char *subdir, const char *subsystem)
404 struct udev *udev = udev_enumerate_get_udev(udev_enumerate);
406 char path[UTIL_PATH_SIZE];
410 util_strscpyl(path, sizeof(path), udev_get_sys_path(udev), "/", basedir, NULL);
414 for (dent = readdir(dir); dent != NULL; dent = readdir(dir)) {
415 if (dent->d_name[0] == '.')
417 if (!match_subsystem(udev_enumerate, subsystem != NULL ? subsystem : dent->d_name))
419 scan_dir_and_add_devices(udev_enumerate, basedir, dent->d_name, subdir);
425 static int devices_delay(struct udev *udev, const char *syspath)
427 static const char *delay_device_list[] = {
435 len = strlen(udev_get_sys_path(udev));
436 for (i = 0; delay_device_list[i] != NULL; i++) {
437 if (strstr(&syspath[len], delay_device_list[i]) != NULL) {
438 dbg(udev, "delaying: %s\n", syspath);
445 /* sort delayed devices to the end of the list */
446 static int devices_sort(struct udev_enumerate *udev_enumerate)
448 struct udev_list_entry *entry_loop;
449 struct udev_list_entry *entry_tmp;
450 struct udev_list_node devices_list;
452 udev_list_init(&devices_list);
453 /* move delayed to delay list */
454 udev_list_entry_foreach_safe(entry_loop, entry_tmp, udev_list_get_entry(&udev_enumerate->devices_list)) {
455 if (devices_delay(udev_enumerate->udev, udev_list_entry_get_name(entry_loop))) {
456 udev_list_entry_remove(entry_loop);
457 udev_list_entry_append(entry_loop, &devices_list);
460 /* move delayed back to end of list */
461 udev_list_entry_foreach_safe(entry_loop, entry_tmp, udev_list_get_entry(&devices_list)) {
462 udev_list_entry_remove(entry_loop);
463 udev_list_entry_append(entry_loop, &udev_enumerate->devices_list);
465 udev_enumerate->devices_sorted = 1;
470 * udev_enumerate_add_syspath:
471 * @udev_enumerate: context
472 * @syspath: path of a device
474 * Add a device to the list of devices, to retrieve it back sorted in dependency order.
476 * Returns: 0 on success, otherwise a negative error value.
478 int udev_enumerate_add_syspath(struct udev_enumerate *udev_enumerate, const char *syspath)
480 struct udev *udev = udev_enumerate_get_udev(udev_enumerate);
481 struct udev_device *udev_device;
483 if (udev_enumerate == NULL)
487 /* resolve to real syspath */
488 udev_device = udev_device_new_from_syspath(udev_enumerate->udev, syspath);
489 if (udev_device == NULL)
491 udev_list_entry_add(udev, &udev_enumerate->devices_list,
492 udev_device_get_syspath(udev_device), NULL, 1, 1);
493 udev_device_unref(udev_device);
498 * udev_enumerate_scan_devices:
499 * @udev_enumerate: udev enumeration context
501 * Returns: 0 on success, otherwise a negative error value.
503 int udev_enumerate_scan_devices(struct udev_enumerate *udev_enumerate)
505 struct udev *udev = udev_enumerate_get_udev(udev_enumerate);
506 char base[UTIL_PATH_SIZE];
509 if (udev_enumerate == NULL)
511 util_strscpyl(base, sizeof(base), udev_get_sys_path(udev), "/subsystem", NULL);
512 if (stat(base, &statbuf) == 0) {
513 /* we have /subsystem/, forget all the old stuff */
514 dbg(udev, "searching '/subsystem/*/devices/*' dir\n");
515 scan_dir(udev_enumerate, "subsystem", "devices", NULL);
517 dbg(udev, "searching '/bus/*/devices/*' dir\n");
518 scan_dir(udev_enumerate, "bus", "devices", NULL);
519 dbg(udev, "searching '/class/*' dir\n");
520 scan_dir(udev_enumerate, "class", NULL, NULL);
521 /* if block isn't a class, scan /block/ */
522 util_strscpyl(base, sizeof(base), udev_get_sys_path(udev), "/class/block", NULL);
523 if (stat(base, &statbuf) != 0) {
524 if (match_subsystem(udev_enumerate, "block")) {
525 dbg(udev, "searching '/block/*' dir\n");
527 scan_dir_and_add_devices(udev_enumerate, "block", NULL, NULL);
528 /* scan partitions */
529 dbg(udev, "searching '/block/*/*' dir\n");
530 scan_dir(udev_enumerate, "block", NULL, "block");
538 * udev_enumerate_scan_subsystems:
539 * @udev_enumerate: udev enumeration context
541 * Returns: 0 on success, otherwise a negative error value.
543 int udev_enumerate_scan_subsystems(struct udev_enumerate *udev_enumerate)
545 struct udev *udev = udev_enumerate_get_udev(udev_enumerate);
546 char base[UTIL_PATH_SIZE];
548 const char *subsysdir;
550 if (udev_enumerate == NULL)
552 util_strscpyl(base, sizeof(base), udev_get_sys_path(udev), "/subsystem", NULL);
553 if (stat(base, &statbuf) == 0)
554 subsysdir = "subsystem";
557 if (match_subsystem(udev_enumerate, "subsystem")) {
558 dbg(udev, "searching '%s/*' dir\n", subsysdir);
559 scan_dir_and_add_devices(udev_enumerate, subsysdir, NULL, NULL);
561 if (match_subsystem(udev_enumerate, "drivers")) {
562 dbg(udev, "searching '%s/*/drivers/*' dir\n", subsysdir);
563 scan_dir(udev_enumerate, subsysdir, "drivers", "drivers");