4 * System utility functions for libsysfs
6 * Copyright (C) IBM Corp. 2003
8 * This library is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
13 * This library is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with this library; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
30 * sysfs_get_mnt_path: Gets the mount point for specified filesystem.
31 * @fs_type: filesystem type to retrieve mount point
32 * @mnt_path: place to put the retrieved mount path
33 * @len: size of mnt_path
34 * returns 0 with success and -1 with error.
36 static int sysfs_get_fs_mnt_path(const unsigned char *fs_type,
37 unsigned char *mnt_path, size_t len)
40 strcpy(mnt_path, "/sys");
44 struct mntent *mntent;
49 if (fs_type == NULL || mnt_path == NULL) {
54 if ((mnt = setmntent(SYSFS_PROC_MNTS, "r")) == NULL) {
55 dprintf("Error getting mount information\n");
58 while (ret == 0 && dirlen == 0 && (mntent = getmntent(mnt)) != NULL) {
59 if (strcmp(mntent->mnt_type, fs_type) == 0) {
60 dirlen = strlen(mntent->mnt_dir);
61 if (dirlen <= (len - 1)) {
62 strcpy(mnt_path, mntent->mnt_dir);
64 dprintf("Error - mount path too long\n");
70 if (dirlen == 0 && ret == 0) {
71 dprintf("Filesystem %s not found!\n", fs_type);
80 * sysfs_trailing_slash: checks if there's a trailing slash to path
81 * @path: path to check
82 * returns 1 if true and 0 if not
84 int sysfs_trailing_slash(unsigned char *path)
86 unsigned char *s = NULL;
90 s = &path[strlen(path)-1];
91 if (strncmp(s, "/", 1) == 0)
97 * sysfs_get_mnt_path: Gets the sysfs mount point.
98 * @mnt_path: place to put "sysfs" mount point
99 * @len: size of mnt_path
100 * returns 0 with success and -1 with error.
102 int sysfs_get_mnt_path(unsigned char *mnt_path, size_t len)
104 char *sysfs_path = NULL;
107 if (mnt_path == NULL) {
111 sysfs_path = getenv(SYSFS_PATH_ENV);
112 if (sysfs_path != NULL)
113 strncpy(mnt_path, sysfs_path, len);
115 ret = sysfs_get_fs_mnt_path(SYSFS_FSTYPE_NAME, mnt_path, len);
121 * sysfs_get_name_from_path: returns last name from a "/" delimited path
122 * @path: path to get name from
123 * @name: where to put name
126 int sysfs_get_name_from_path(const unsigned char *path, unsigned char *name,
129 unsigned char tmp[SYSFS_PATH_MAX];
130 unsigned char *n = NULL;
132 if (path == NULL || name == NULL) {
136 memset(tmp, 0, SYSFS_PATH_MAX);
138 n = strrchr(tmp, '/');
143 if (*(n+1) == '\0') {
145 n = strrchr(tmp, '/');
152 strncpy(name, n, len);
157 * sysfs_get_link: returns link source
158 * @path: symbolic link's path
159 * @target: where to put name
162 int sysfs_get_link(const unsigned char *path, unsigned char *target, size_t len)
164 unsigned char devdir[SYSFS_PATH_MAX];
165 unsigned char linkpath[SYSFS_PATH_MAX];
166 unsigned char *d = NULL, *s = NULL;
167 int slashes = 0, count = 0;
169 if (path == NULL || target == NULL) {
174 memset(devdir, 0, SYSFS_PATH_MAX);
175 memset(linkpath, 0, SYSFS_PATH_MAX);
176 strncpy(devdir, path, SYSFS_PATH_MAX);
178 if ((readlink(path, linkpath, SYSFS_PATH_MAX)) < 0) {
184 /* getting rid of leading "../.." */
185 while (*d == '/' || *d == '.') {
193 s = &devdir[strlen(devdir)-1];
194 while (s != NULL && count != (slashes+1)) {
200 strncpy(s, d, (SYSFS_PATH_MAX-strlen(devdir)));
201 strncpy(target, devdir, len);
208 * sysfs_del_name: free function for sysfs_open_subsystem_list
209 * @name: memory area to be freed
211 static void sysfs_del_name(void *name)
218 * sysfs_close_list: generic list free routine
219 * @list: dlist to free
222 void sysfs_close_list(struct dlist *list)
229 * sysfs_open_subsystem_list: gets a list of all supported "name" subsystem
230 * details from the system
231 * @name: name of the subsystem, eg., "bus", "class", "devices"
232 * Returns a dlist of supported names or NULL if subsystem not supported
234 struct dlist *sysfs_open_subsystem_list(unsigned char *name)
236 unsigned char sysfs_path[SYSFS_PATH_MAX], *subsys_name = NULL;
237 unsigned char *c = NULL;
238 struct sysfs_directory *dir = NULL, *cur = NULL;
239 struct dlist *list = NULL;
244 if (sysfs_get_mnt_path(sysfs_path, SYSFS_PATH_MAX) != 0) {
245 dprintf("Error getting sysfs mount point\n");
248 if (sysfs_trailing_slash(sysfs_path) == 0)
249 strcat(sysfs_path, "/");
250 strcat(sysfs_path, name);
251 dir = sysfs_open_directory(sysfs_path);
253 dprintf("Error opening sysfs_directory at %s\n", sysfs_path);
257 if ((sysfs_read_dir_subdirs(dir)) != 0) {
258 dprintf("Error reading sysfs_directory at %s\n", sysfs_path);
259 sysfs_close_directory(dir);
263 if (dir->subdirs != NULL) {
264 list = dlist_new_with_delete(SYSFS_NAME_LEN,
267 dprintf("Error creating list\n");
268 sysfs_close_directory(dir);
272 dlist_for_each_data(dir->subdirs, cur,
273 struct sysfs_directory) {
274 subsys_name = (char *)calloc(1, SYSFS_NAME_LEN);
275 strcpy(subsys_name, cur->name);
276 dlist_unshift(list, subsys_name);
279 sysfs_close_directory(dir);
281 * We are now considering "block" as a "class". Hence, if the subsys
282 * name requested here is "class", verify if "block" is supported on
283 * this system and return the same.
285 if (strcmp(name, SYSFS_CLASS_NAME) == 0) {
286 c = strstr(sysfs_path, SYSFS_CLASS_NAME);
289 strcpy(c, SYSFS_BLOCK_NAME);
290 if ((sysfs_path_is_dir(sysfs_path)) == 0) {
291 subsys_name = (char *)calloc(1, SYSFS_NAME_LEN);
292 strcpy(subsys_name, SYSFS_BLOCK_NAME);
293 dlist_unshift(list, subsys_name);
302 * sysfs_open_bus_devices_list: gets a list of all devices on "name" bus
303 * @name: name of the subsystem, eg., "pci", "scsi", "usb"
304 * Returns a dlist of supported names or NULL if subsystem not supported
306 struct dlist *sysfs_open_bus_devices_list(unsigned char *name)
308 unsigned char sysfs_path[SYSFS_PATH_MAX], *device_name = NULL;
309 struct sysfs_directory *dir = NULL;
310 struct sysfs_link *cur = NULL;
311 struct dlist *list = NULL;
316 if (sysfs_get_mnt_path(sysfs_path, SYSFS_PATH_MAX) != 0) {
317 dprintf("Error getting sysfs mount point\n");
321 if (sysfs_trailing_slash(sysfs_path) == 0)
322 strcat(sysfs_path, "/");
323 strcat(sysfs_path, SYSFS_BUS_NAME);
324 strcat(sysfs_path, "/");
325 strcat(sysfs_path, name);
326 strcat(sysfs_path, "/");
327 strcat(sysfs_path, SYSFS_DEVICES_NAME);
328 dir = sysfs_open_directory(sysfs_path);
330 dprintf("Error opening sysfs_directory at %s\n", sysfs_path);
334 if ((sysfs_read_dir_links(dir)) != 0) {
335 dprintf("Error reading sysfs_directory at %s\n", sysfs_path);
336 sysfs_close_directory(dir);
340 if (dir->links != NULL) {
341 list = dlist_new_with_delete(SYSFS_NAME_LEN,
344 dprintf("Error creating list\n");
345 sysfs_close_directory(dir);
349 dlist_for_each_data(dir->links, cur,
351 device_name = (char *)calloc(1, SYSFS_NAME_LEN);
352 strcpy(device_name, cur->name);
353 dlist_unshift(list, device_name);
356 sysfs_close_directory(dir);
361 * sysfs_path_is_dir: Check if the path supplied points to a directory
362 * @path: path to validate
363 * Returns 0 if path points to dir, 1 otherwise
365 int sysfs_path_is_dir(const unsigned char *path)
373 if ((lstat(path, &astats)) != 0) {
374 dprintf("stat() failed\n");
377 if (S_ISDIR(astats.st_mode))
384 * sysfs_path_is_link: Check if the path supplied points to a link
385 * @path: path to validate
386 * Returns 0 if path points to link, 1 otherwise
388 int sysfs_path_is_link(const unsigned char *path)
396 if ((lstat(path, &astats)) != 0) {
397 dprintf("stat() failed\n");
400 if (S_ISLNK(astats.st_mode))
407 * sysfs_path_is_file: Check if the path supplied points to a file
408 * @path: path to validate
409 * Returns 0 if path points to file, 1 otherwise
411 int sysfs_path_is_file(const unsigned char *path)
419 if ((lstat(path, &astats)) != 0) {
420 dprintf("stat() failed\n");
423 if (S_ISREG(astats.st_mode))