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_get_mnt_path: Gets the sysfs mount point.
81 * @mnt_path: place to put "sysfs" mount point
82 * @len: size of mnt_path
83 * returns 0 with success and -1 with error.
85 int sysfs_get_mnt_path(unsigned char *mnt_path, size_t len)
87 char *sysfs_path = NULL;
90 if (mnt_path == NULL) {
94 sysfs_path = getenv(SYSFS_PATH_ENV);
95 if (sysfs_path != NULL)
96 strncpy(mnt_path, sysfs_path, len);
98 ret = sysfs_get_fs_mnt_path(SYSFS_FSTYPE_NAME, mnt_path, len);
104 * sysfs_get_name_from_path: returns last name from a "/" delimited path
105 * @path: path to get name from
106 * @name: where to put name
109 int sysfs_get_name_from_path(const unsigned char *path, unsigned char *name,
112 unsigned char tmp[SYSFS_PATH_MAX];
113 unsigned char *n = NULL;
115 if (path == NULL || name == NULL) {
119 memset(tmp, 0, SYSFS_PATH_MAX);
121 n = &tmp[strlen(tmp)-1];
122 if (strncmp(n, "/", 1) == 0)
124 n = strrchr(tmp, '/');
130 strncpy(name, n, len);
136 * sysfs_get_link: returns link source
137 * @path: symbolic link's path
138 * @target: where to put name
141 int sysfs_get_link(const unsigned char *path, unsigned char *target, size_t len)
143 unsigned char devdir[SYSFS_PATH_MAX];
144 unsigned char linkpath[SYSFS_PATH_MAX];
145 unsigned char *d = NULL, *s = NULL;
146 int slashes = 0, count = 0;
148 if (path == NULL || target == NULL) {
153 memset(devdir, 0, SYSFS_PATH_MAX);
154 memset(linkpath, 0, SYSFS_PATH_MAX);
155 strncpy(devdir, path, SYSFS_PATH_MAX);
157 if ((readlink(path, linkpath, SYSFS_PATH_MAX)) < 0) {
163 /* getting rid of leading "../.." */
164 while (*d == '/' || *d == '.') {
172 s = &devdir[strlen(devdir)-1];
173 while (s != NULL && count != (slashes+1)) {
179 strncpy(s, d, (SYSFS_PATH_MAX-strlen(devdir)));
180 strncpy(target, devdir, len);
187 * sysfs_del_name: free function for sysfs_open_subsystem_list
188 * @name: memory area to be freed
190 static void sysfs_del_name(void *name)
197 * sysfs_close_list: generic list free routine
198 * @list: dlist to free
201 void sysfs_close_list(struct dlist *list)
208 * sysfs_open_subsystem_list: gets a list of all supported "name" subsystem
209 * details from the system
210 * @name: name of the subsystem, eg., "bus", "class", "devices"
211 * Returns a dlist of supported names or NULL if subsystem not supported
213 struct dlist *sysfs_open_subsystem_list(unsigned char *name)
215 unsigned char sysfs_path[SYSFS_PATH_MAX], *subsys_name = NULL;
216 unsigned char *c = NULL;
217 struct sysfs_directory *dir = NULL, *cur = NULL;
218 struct dlist *list = NULL;
224 if (sysfs_get_mnt_path(sysfs_path, SYSFS_PATH_MAX) != 0) {
225 dprintf("Error getting sysfs mount point\n");
229 strcat(sysfs_path, name);
230 dir = sysfs_open_directory(sysfs_path);
232 dprintf("Error opening sysfs_directory at %s\n", sysfs_path);
236 if (sysfs_read_directory(dir) != 0) {
237 dprintf("Error reading sysfs_directory at %s\n", sysfs_path);
238 sysfs_close_directory(dir);
242 if (dir->subdirs != NULL) {
243 list = dlist_new_with_delete(SYSFS_NAME_LEN,
246 dprintf("Error creating list\n");
247 sysfs_close_directory(dir);
251 dlist_for_each_data(dir->subdirs, cur,
252 struct sysfs_directory) {
253 subsys_name = (char *)calloc(1, SYSFS_NAME_LEN);
254 strcpy(subsys_name, cur->name);
255 dlist_unshift(list, subsys_name);
258 sysfs_close_directory(dir);
260 * We are now considering "block" as a "class". Hence, if the subsys
261 * name requested here is "class", verify if "block" is supported on
262 * this system and return the same.
264 if (strcmp(name, SYSFS_CLASS_DIR) == 0) {
265 c = strstr(sysfs_path, SYSFS_CLASS_NAME);
268 strcpy(c, SYSFS_BLOCK_NAME);
269 if ((lstat(sysfs_path, &astats)) != 0) {
270 dprintf("stat() failed\n");
273 if (S_ISDIR(astats.st_mode)) {
274 subsys_name = (char *)calloc(1, SYSFS_NAME_LEN);
275 strcpy(subsys_name, SYSFS_BLOCK_NAME);
276 dlist_unshift(list, subsys_name);
285 * sysfs_open_bus_devices_list: gets a list of all devices on "name" bus
286 * @name: name of the subsystem, eg., "pci", "scsi", "usb"
287 * Returns a dlist of supported names or NULL if subsystem not supported
289 struct dlist *sysfs_open_bus_devices_list(unsigned char *name)
291 unsigned char sysfs_path[SYSFS_PATH_MAX], *device_name = NULL;
292 struct sysfs_directory *dir = NULL;
293 struct sysfs_link *cur = NULL;
294 struct dlist *list = NULL;
299 if (sysfs_get_mnt_path(sysfs_path, SYSFS_PATH_MAX) != 0) {
300 dprintf("Error getting sysfs mount point\n");
304 strcat(sysfs_path, SYSFS_BUS_DIR);
305 strcat(sysfs_path, "/");
306 strcat(sysfs_path, name);
307 strcat(sysfs_path, SYSFS_DEVICES_DIR);
308 dir = sysfs_open_directory(sysfs_path);
310 dprintf("Error opening sysfs_directory at %s\n", sysfs_path);
314 if (sysfs_read_directory(dir) != 0) {
315 dprintf("Error reading sysfs_directory at %s\n", sysfs_path);
316 sysfs_close_directory(dir);
320 if (dir->links != NULL) {
321 list = dlist_new_with_delete(SYSFS_NAME_LEN,
324 dprintf("Error creating list\n");
325 sysfs_close_directory(dir);
329 dlist_for_each_data(dir->links, cur,
331 device_name = (char *)calloc(1, SYSFS_NAME_LEN);
332 strcpy(device_name, cur->name);
333 dlist_unshift(list, device_name);
336 sysfs_close_directory(dir);