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Diffstat (limited to 'udev_sysfs.c')
-rw-r--r--udev_sysfs.c82
1 files changed, 36 insertions, 46 deletions
diff --git a/udev_sysfs.c b/udev_sysfs.c
index 0b7561f0eb..0e448894fe 100644
--- a/udev_sysfs.c
+++ b/udev_sysfs.c
@@ -112,6 +112,38 @@ void sysfs_device_set_values(struct sysfs_device *dev, const char *devpath,
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];
@@ -144,27 +176,8 @@ struct sysfs_device *sysfs_device_get(const char *devpath)
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) {
@@ -247,12 +260,7 @@ struct sysfs_device *sysfs_device_get(const char *devpath)
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);
@@ -298,28 +306,10 @@ struct sysfs_device *sysfs_device_get_parent(struct sysfs_device *dev)
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);