+ if (strcmp(subsystem, "drivers") == 0) {
+ char subsys[UTIL_NAME_SIZE];
+ char *driver;
+
+ util_strlcpy(subsys, sysname, sizeof(subsys));
+ driver = strchr(subsys, ':');
+ if (driver != NULL) {
+ driver[0] = '\0';
+ driver = &driver[1];
+ util_strlcpy(path, "/subsystem/", sizeof(path_full) - sys_path_len);
+ util_strlcat(path, subsys, sizeof(path_full) - sys_path_len);
+ util_strlcat(path, "/drivers/", sizeof(path_full) - sys_path_len);
+ util_strlcat(path, driver, sizeof(path_full) - sys_path_len);
+ if (stat(path_full, &statbuf) == 0)
+ goto found;
+
+ util_strlcpy(path, "/bus/", sizeof(path_full) - sys_path_len);
+ util_strlcat(path, subsys, sizeof(path_full) - sys_path_len);
+ util_strlcat(path, "/drivers/", sizeof(path_full) - sys_path_len);
+ util_strlcat(path, driver, sizeof(path_full) - sys_path_len);
+ if (stat(path_full, &statbuf) == 0)
+ goto found;
+ }
+ goto out;
+ }
+
+ util_strlcpy(path, "/subsystem/", sizeof(path_full) - sys_path_len);
+ util_strlcat(path, subsystem, sizeof(path_full) - sys_path_len);
+ util_strlcat(path, "/devices/", sizeof(path_full) - sys_path_len);
+ util_strlcat(path, sysname, sizeof(path_full) - sys_path_len);
+ if (stat(path_full, &statbuf) == 0)
+ goto found;
+
+ util_strlcpy(path, "/bus/", sizeof(path_full) - sys_path_len);
+ util_strlcat(path, subsystem, sizeof(path_full) - sys_path_len);
+ util_strlcat(path, "/devices/", sizeof(path_full) - sys_path_len);
+ util_strlcat(path, sysname, sizeof(path_full) - sys_path_len);
+ if (stat(path_full, &statbuf) == 0)
+ goto found;
+
+ util_strlcpy(path, "/class/", sizeof(path_full) - sys_path_len);
+ util_strlcat(path, subsystem, sizeof(path_full) - sys_path_len);
+ util_strlcat(path, "/", sizeof(path_full) - sys_path_len);
+ util_strlcat(path, sysname, sizeof(path_full) - sys_path_len);
+ if (stat(path_full, &statbuf) == 0)
+ goto found;
+out:
+ return NULL;
+found:
+ return udev_device_new_from_syspath(udev, path_full);
+}
+
+static struct udev_device *device_new_from_parent(struct udev_device *udev_device)
+{
+ struct udev_device *udev_device_parent = NULL;
+ char path[UTIL_PATH_SIZE];
+ const char *subdir;
+
+ /* follow "device" link in deprecated sys layout */
+ if (strncmp(udev_device->devpath, "/class/", 7) == 0 ||
+ strncmp(udev_device->devpath, "/block/", 7) == 0) {
+ util_strlcpy(path, udev_device->syspath, sizeof(path));
+ util_strlcat(path, "/device", sizeof(path));
+ if (util_resolve_sys_link(udev_device->udev, path, sizeof(path)) == 0)
+ udev_device_parent = udev_device_new_from_syspath(udev_device->udev, path);
+ return udev_device_parent;
+ }
+
+ util_strlcpy(path, udev_device->syspath, sizeof(path));
+ subdir = &path[strlen(udev_get_sys_path(udev_device->udev))+1];
+ while (1) {
+ char *pos;
+
+ pos = strrchr(subdir, '/');
+ if (pos == NULL || pos < &subdir[2])
+ break;
+ pos[0] = '\0';
+ udev_device_parent = udev_device_new_from_syspath(udev_device->udev, path);
+ if (udev_device_parent != NULL)
+ return udev_device_parent;
+ }
+ return NULL;
+}
+
+struct udev_device *udev_device_get_parent(struct udev_device *udev_device)
+{
+ if (udev_device == NULL)
+ return NULL;
+
+ if (udev_device->parent_device != NULL) {
+ info(udev_device->udev, "returning existing parent %p\n", udev_device->parent_device);
+ return udev_device->parent_device;
+ }
+ udev_device->parent_device = device_new_from_parent(udev_device);
+ return udev_device->parent_device;
+}
+
+struct udev_device *udev_device_get_parent_with_subsystem(struct udev_device *udev_device, const char *subsystem)
+{
+ struct udev_device *parent;
+
+ parent = udev_device_get_parent(udev_device);
+ while (parent != NULL) {
+ const char *parent_subsystem;
+
+ parent_subsystem = udev_device_get_subsystem(parent);
+ if (parent_subsystem != NULL && strcmp(parent_subsystem, subsystem) == 0)
+ break;
+ parent = udev_device_get_parent(parent);
+ }
+ return parent;