diff options
| -rw-r--r-- | udev.h | 1 | ||||
| -rw-r--r-- | udev_sysfs.c | 82 |
2 files changed, 37 insertions, 46 deletions
@@ -113,6 +113,7 @@ extern struct sysfs_device *sysfs_device_get(const char *devpath); extern struct sysfs_device *sysfs_device_get_parent(struct sysfs_device *dev); extern struct sysfs_device *sysfs_device_get_parent_with_subsystem(struct sysfs_device *dev, const char *subsystem); extern char *sysfs_attr_get_value(const char *devpath, const char *attr_name); +extern int sysfs_resolve_link(char *path, size_t size); /* udev_node.c */ extern int udev_node_mknod(struct udevice *udev, const char *file, dev_t devt, mode_t mode, uid_t uid, gid_t gid); diff --git a/udev_sysfs.c b/udev_sysfs.c index 0b7561f0..0e448894 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); |