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 = &tmp[strlen(tmp)-1];
139 if (strncmp(n, "/", 1) == 0)
141 n = strrchr(tmp, '/');
147 strncpy(name, n, len);
153 * sysfs_get_link: returns link source
154 * @path: symbolic link's path
155 * @target: where to put name
158 int sysfs_get_link(const unsigned char *path, unsigned char *target, size_t len)
160 unsigned char devdir[SYSFS_PATH_MAX];
161 unsigned char linkpath[SYSFS_PATH_MAX];
162 unsigned char *d = NULL, *s = NULL;
163 int slashes = 0, count = 0;
165 if (path == NULL || target == NULL) {
170 memset(devdir, 0, SYSFS_PATH_MAX);
171 memset(linkpath, 0, SYSFS_PATH_MAX);
172 strncpy(devdir, path, SYSFS_PATH_MAX);
174 if ((readlink(path, linkpath, SYSFS_PATH_MAX)) < 0) {
180 /* getting rid of leading "../.." */
181 while (*d == '/' || *d == '.') {
189 s = &devdir[strlen(devdir)-1];
190 while (s != NULL && count != (slashes+1)) {
196 strncpy(s, d, (SYSFS_PATH_MAX-strlen(devdir)));
197 strncpy(target, devdir, len);
204 * sysfs_del_name: free function for sysfs_open_subsystem_list
205 * @name: memory area to be freed
207 static void sysfs_del_name(void *name)
214 * sysfs_close_list: generic list free routine
215 * @list: dlist to free
218 void sysfs_close_list(struct dlist *list)
225 * sysfs_open_subsystem_list: gets a list of all supported "name" subsystem
226 * details from the system
227 * @name: name of the subsystem, eg., "bus", "class", "devices"
228 * Returns a dlist of supported names or NULL if subsystem not supported
230 struct dlist *sysfs_open_subsystem_list(unsigned char *name)
232 unsigned char sysfs_path[SYSFS_PATH_MAX], *subsys_name = NULL;
233 unsigned char *c = NULL;
234 struct sysfs_directory *dir = NULL, *cur = NULL;
235 struct dlist *list = NULL;
241 if (sysfs_get_mnt_path(sysfs_path, SYSFS_PATH_MAX) != 0) {
242 dprintf("Error getting sysfs mount point\n");
246 if (sysfs_trailing_slash(sysfs_path) == 0)
247 strcat(sysfs_path, "/");
248 strcat(sysfs_path, name);
249 dir = sysfs_open_directory(sysfs_path);
251 dprintf("Error opening sysfs_directory at %s\n", sysfs_path);
255 if (sysfs_read_directory(dir) != 0) {
256 dprintf("Error reading sysfs_directory at %s\n", sysfs_path);
257 sysfs_close_directory(dir);
261 if (dir->subdirs != NULL) {
262 list = dlist_new_with_delete(SYSFS_NAME_LEN,
265 dprintf("Error creating list\n");
266 sysfs_close_directory(dir);
270 dlist_for_each_data(dir->subdirs, cur,
271 struct sysfs_directory) {
272 subsys_name = (char *)calloc(1, SYSFS_NAME_LEN);
273 strcpy(subsys_name, cur->name);
274 dlist_unshift(list, subsys_name);
277 sysfs_close_directory(dir);
279 * We are now considering "block" as a "class". Hence, if the subsys
280 * name requested here is "class", verify if "block" is supported on
281 * this system and return the same.
283 if (strcmp(name, SYSFS_CLASS_DIR) == 0) {
284 c = strstr(sysfs_path, SYSFS_CLASS_NAME);
287 strcpy(c, SYSFS_BLOCK_NAME);
288 if ((lstat(sysfs_path, &astats)) != 0) {
289 dprintf("stat() failed\n");
292 if (S_ISDIR(astats.st_mode)) {
293 subsys_name = (char *)calloc(1, SYSFS_NAME_LEN);
294 strcpy(subsys_name, SYSFS_BLOCK_NAME);
295 dlist_unshift(list, subsys_name);
304 * sysfs_open_bus_devices_list: gets a list of all devices on "name" bus
305 * @name: name of the subsystem, eg., "pci", "scsi", "usb"
306 * Returns a dlist of supported names or NULL if subsystem not supported
308 struct dlist *sysfs_open_bus_devices_list(unsigned char *name)
310 unsigned char sysfs_path[SYSFS_PATH_MAX], *device_name = NULL;
311 struct sysfs_directory *dir = NULL;
312 struct sysfs_link *cur = NULL;
313 struct dlist *list = NULL;
318 if (sysfs_get_mnt_path(sysfs_path, SYSFS_PATH_MAX) != 0) {
319 dprintf("Error getting sysfs mount point\n");
323 if (sysfs_trailing_slash(sysfs_path) == 0)
324 strcat(sysfs_path, "/");
325 strcat(sysfs_path, SYSFS_BUS_NAME);
326 strcat(sysfs_path, "/");
327 strcat(sysfs_path, name);
328 strcat(sysfs_path, SYSFS_DEVICES_DIR);
329 dir = sysfs_open_directory(sysfs_path);
331 dprintf("Error opening sysfs_directory at %s\n", sysfs_path);
335 if (sysfs_read_directory(dir) != 0) {
336 dprintf("Error reading sysfs_directory at %s\n", sysfs_path);
337 sysfs_close_directory(dir);
341 if (dir->links != NULL) {
342 list = dlist_new_with_delete(SYSFS_NAME_LEN,
345 dprintf("Error creating list\n");
346 sysfs_close_directory(dir);
350 dlist_for_each_data(dir->links, cur,
352 device_name = (char *)calloc(1, SYSFS_NAME_LEN);
353 strcpy(device_name, cur->name);
354 dlist_unshift(list, device_name);
357 sysfs_close_directory(dir);