/*
- * udev_sysfs.c - sysfs access
- *
- * Copyright (C) 2005 Kay Sievers <kay.sievers@vrfy.org>
+ * Copyright (C) 2005-2006 Kay Sievers <kay.sievers@vrfy.org>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
- * 675 Mass Ave, Cambridge, MA 02139, USA.
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
*/
if (pos == NULL)
return;
- strlcpy(dev->kernel_name, &pos[1], sizeof(dev->kernel_name));
- dbg("kernel_name='%s'", dev->kernel_name);
+ strlcpy(dev->kernel, &pos[1], sizeof(dev->kernel));
+ dbg("kernel='%s'", dev->kernel);
/* some devices have '!' in their name, change that to '/' */
- pos = dev->kernel_name;
+ pos = dev->kernel;
while (pos[0] != '\0') {
if (pos[0] == '!')
pos[0] = '/';
}
/* get kernel number */
- pos = &dev->kernel_name[strlen(dev->kernel_name)];
+ pos = &dev->kernel[strlen(dev->kernel)];
while (isdigit(pos[-1]))
pos--;
strlcpy(dev->kernel_number, pos, sizeof(dev->kernel_number));
dbg("kernel_number='%s'", dev->kernel_number);
}
+int sysfs_resolve_link(char *devpath, size_t size)
+{
+ char link_path[PATH_SIZE];
+ char link_target[PATH_SIZE];
+ int len;
+ int i;
+ int back;
+
+ strlcpy(link_path, sysfs_path, sizeof(link_path));
+ strlcat(link_path, devpath, sizeof(link_path));
+ len = readlink(link_path, link_target, sizeof(link_target));
+ if (len <= 0)
+ return -1;
+ link_target[len] = '\0';
+ dbg("path link '%s' points to '%s'", devpath, link_target);
+
+ for (back = 0; strncmp(&link_target[back * 3], "../", 3) == 0; back++)
+ ;
+ dbg("base '%s', tail '%s', back %i", devpath, &link_target[back * 3], back);
+ for (i = 0; i <= back; i++) {
+ char *pos = strrchr(devpath, '/');
+
+ if (pos == NULL)
+ return -1;
+ pos[0] = '\0';
+ }
+ dbg("after moving back '%s'", devpath);
+ strlcat(devpath, "/", size);
+ strlcat(devpath, &link_target[back * 3], size);
+ return 0;
+}
+
struct sysfs_device *sysfs_device_get(const char *devpath)
{
char path[PATH_SIZE];
return NULL;
}
if (S_ISLNK(statbuf.st_mode)) {
- int i;
- int back;
-
- len = readlink(path, link_target, sizeof(link_target));
- if (len <= 0)
+ if (sysfs_resolve_link(devpath_real, sizeof(devpath_real)) != 0)
return NULL;
- link_target[len] = '\0';
- dbg("devpath link '%s' points to '%s'", path, link_target);
-
- for (back = 0; strncmp(&link_target[back * 3], "../", 3) == 0; back++)
- ;
- dbg("base '%s', tail '%s', back %i", devpath_real, &link_target[back * 3], back);
- for (i = 0; i <= back; i++) {
- pos = strrchr(devpath_real, '/');
- if (pos == NULL)
- return NULL;
- pos[0] = '\0';
- }
- dbg("after moving back '%s'", devpath_real);
- strlcat(devpath_real, "/", sizeof(devpath_real));
- strlcat(devpath_real, &link_target[back * 3], sizeof(devpath_real));
/* now look for device in cache after path translation */
list_for_each_entry(dev_loop, &dev_list, node) {
sysfs_device_set_values(dev, devpath_real, NULL, NULL);
- /* get subsystem */
- if (strncmp(dev->devpath, "/class/", 7) == 0) {
+ /* get subsystem name */
+ strlcpy(link_path, sysfs_path, sizeof(link_path));
+ strlcat(link_path, dev->devpath, sizeof(link_path));
+ strlcat(link_path, "/subsystem", sizeof(link_path));
+ len = readlink(link_path, link_target, sizeof(link_target));
+ if (len > 0) {
+ /* get subsystem from "subsystem" link */
+ link_target[len] = '\0';
+ dbg("subsystem link '%s' points to '%s'", link_path, link_target);
+ pos = strrchr(link_target, '/');
+ if (pos != NULL)
+ strlcpy(dev->subsystem, &pos[1], sizeof(dev->subsystem));
+ } else if (strncmp(dev->devpath, "/class/", 7) == 0) {
+ /* get subsystem from class dir */
strlcpy(dev->subsystem, &dev->devpath[7], sizeof(dev->subsystem));
pos = strchr(dev->subsystem, '/');
if (pos != NULL)
pos = strrchr(link_target, '/');
if (pos != NULL)
strlcpy(dev->subsystem, &pos[1], sizeof(dev->subsystem));
- } else {
- /* get subsystem from "subsystem" link */
- strlcpy(link_path, sysfs_path, sizeof(link_path));
- strlcat(link_path, dev->devpath, sizeof(link_path));
- strlcat(link_path, "/subsystem", sizeof(link_path));
- len = readlink(link_path, link_target, sizeof(link_target));
- if (len > 0) {
- link_target[len] = '\0';
- dbg("subsystem link '%s' points to '%s'", link_path, link_target);
- pos = strrchr(link_target, '/');
- if (pos != NULL)
- strlcpy(dev->subsystem, &pos[1], sizeof(dev->subsystem));
- }
}
- /* get driver name */
- strlcpy(link_path, sysfs_path, sizeof(link_path));
- strlcat(link_path, dev->devpath, sizeof(link_path));
- strlcat(link_path, "/driver", sizeof(link_path));
- len = readlink(link_path, link_target, sizeof(link_target));
- if (len > 0) {
- link_target[len] = '\0';
- dbg("driver link '%s' points to '%s'", link_path, link_target);
- pos = strrchr(link_target, '/');
- if (pos != NULL)
- strlcpy(dev->driver, &pos[1], sizeof(dev->driver));
- }
- } else if (strncmp(dev->devpath, "/bus/", 5) == 0 && strstr(dev->devpath, "/drivers/")) {
+ } else if (strstr(dev->devpath, "/drivers/") != NULL) {
strlcpy(dev->subsystem, "drivers", sizeof(dev->subsystem));
} else if (strncmp(dev->devpath, "/module/", 8) == 0) {
strlcpy(dev->subsystem, "module", sizeof(dev->subsystem));
}
+ /* get driver name */
+ strlcpy(link_path, sysfs_path, sizeof(link_path));
+ strlcat(link_path, dev->devpath, sizeof(link_path));
+ strlcat(link_path, "/driver", sizeof(link_path));
+ len = readlink(link_path, link_target, sizeof(link_target));
+ if (len > 0) {
+ link_target[len] = '\0';
+ dbg("driver link '%s' points to '%s'", link_path, link_target);
+ pos = strrchr(link_target, '/');
+ if (pos != NULL)
+ strlcpy(dev->driver, &pos[1], sizeof(dev->driver));
+ }
+
dbg("add to cache 'devpath=%s', subsystem='%s', driver='%s'", dev->devpath, dev->subsystem, dev->driver);
list_add(&dev->node, &dev_list);
struct sysfs_device *sysfs_device_get_parent(struct sysfs_device *dev)
{
char parent_devpath[PATH_SIZE];
- char device_link[PATH_SIZE];
- char device_link_target[PATH_SIZE];
char *pos;
- int i;
- int len;
- int back;
dbg("open '%s'", dev->devpath);
/* requesting a parent is only valid for devices */
if ((strncmp(dev->devpath, "/devices/", 9) != 0) &&
+ (strncmp(dev->devpath, "/subsystem/", 11) != 0) &&
(strncmp(dev->devpath, "/class/", 7) != 0) &&
(strncmp(dev->devpath, "/block/", 7) != 0))
return NULL;
return NULL;
}
- /* at the top level of class/block we want to follow the "device" link */
- if (strcmp(parent_devpath, "/block") == 0) {
- dbg("/block top level, look for device link");
- goto device_link;
+ /* at the subsystems top level we want to follow the old-style "device" link */
+ if (strncmp(parent_devpath, "/subsystem", 10) == 0) {
+ pos = strrchr(parent_devpath, '/');
+ if (pos == &parent_devpath[10] || pos == parent_devpath || strcmp(pos, "/devices") == 0) {
+ dbg("/subsystem top level, look for device link");
+ goto device_link;
+ }
}
if (strncmp(parent_devpath, "/class", 6) == 0) {
pos = strrchr(parent_devpath, '/');
goto device_link;
}
}
+ if (strcmp(parent_devpath, "/block") == 0) {
+ dbg("/block top level, look for device link");
+ goto device_link;
+ }
+
/* get parent and remember it */
dev->parent = sysfs_device_get(parent_devpath);
return dev->parent;
device_link:
- strlcpy(device_link, sysfs_path, sizeof(device_link));
- strlcat(device_link, dev->devpath, sizeof(device_link));
- strlcat(device_link, "/device", sizeof(device_link));
- len = readlink(device_link, device_link_target, sizeof(device_link_target));
- if (len < 0)
- return NULL;
- device_link_target[len] = '\0';
- dbg("device link '%s' points to '%s'", device_link, device_link_target);
-
- for (back = 0; strncmp(&device_link_target[back * 3], "../", 3) == 0; back++)
- ;
strlcpy(parent_devpath, dev->devpath, sizeof(parent_devpath));
- dbg("base='%s', tail='%s', back=%i", parent_devpath, &device_link_target[back * 3], back);
- for (i = 0; i < back; i++) {
- pos = strrchr(parent_devpath, '/');
- if (pos == NULL)
- return NULL;
- pos[0] = '\0';
- }
- dbg("after moving back '%s'", parent_devpath);
- strlcat(parent_devpath, "/", sizeof(parent_devpath));
- strlcat(parent_devpath, &device_link_target[back * 3], sizeof(parent_devpath));
+ strlcat(parent_devpath, "/device", sizeof(parent_devpath));
+ if (sysfs_resolve_link(parent_devpath, sizeof(parent_devpath)) != 0)
+ return NULL;
/* get parent and remember it */
dev->parent = sysfs_device_get(parent_devpath);
char value[NAME_SIZE];
struct sysfs_attr *attr_loop;
struct sysfs_attr *attr;
+ struct stat statbuf;
int fd;
ssize_t size;
size_t sysfs_len;
dbg("add to cache '%s'", path_full);
list_add(&attr->node, &attr_list);
+ if (lstat(path_full, &statbuf) != 0) {
+ dbg("stat '%s' failed: %s", path_full, strerror(errno));
+ goto out;
+ }
+
+ if (S_ISLNK(statbuf.st_mode)) {
+ /* links return the last element of the target path */
+ char link_target[PATH_SIZE];
+ int len;
+ const char *pos;
+
+ len = readlink(path_full, link_target, sizeof(link_target));
+ if (len > 0) {
+ link_target[len] = '\0';
+ pos = strrchr(link_target, '/');
+ if (pos != NULL) {
+ dbg("cache '%s' with link value '%s'", path_full, value);
+ strlcpy(attr->value_local, &pos[1], sizeof(attr->value_local));
+ attr->value = attr->value_local;
+ }
+ }
+ goto out;
+ }
+
+ /* skip directories */
+ if (S_ISDIR(statbuf.st_mode))
+ goto out;
+
+ /* skip non-readable files */
+ if ((statbuf.st_mode & S_IRUSR) == 0)
+ goto out;
+
/* read attribute value */
fd = open(path_full, O_RDONLY);
if (fd < 0) {
/* got a valid value, store and return it */
value[size] = '\0';
remove_trailing_chars(value, '\n');
- dbg("cache '%s' with value '%s'", path_full, value);
+ dbg("cache '%s' with attribute value '%s'", path_full, value);
strlcpy(attr->value_local, value, sizeof(attr->value_local));
attr->value = attr->value_local;