+#ifdef UBIFS_EXTROOT
+static int find_ubi_vol(libubi_t libubi, char *name, int *dev_num, int *vol_id)
+{
+ int dev = 0;
+
+ while (ubi_dev_present(libubi, dev))
+ {
+ struct ubi_dev_info dev_info;
+ struct ubi_vol_info vol_info;
+
+ if (ubi_get_dev_info1(libubi, dev++, &dev_info))
+ continue;
+ if (ubi_get_vol_info1_nm(libubi, dev_info.dev_num, name, &vol_info))
+ continue;
+
+ *dev_num = dev_info.dev_num;
+ *vol_id = vol_info.vol_id;
+
+ return 0;
+ }
+
+ return -1;
+}
+
+static int find_block_ubi(libubi_t libubi, char *name, char *part, int plen)
+{
+ int dev_num;
+ int vol_id;
+ int err = -1;
+
+ err = find_ubi_vol(libubi, name, &dev_num, &vol_id);
+ if (!err)
+ snprintf(part, plen, "/dev/ubi%d_%d", dev_num, vol_id);
+
+ return err;
+}
+
+static int find_block_ubi_RO(libubi_t libubi, char *name, char *part, int plen)
+{
+ int dev_num;
+ int vol_id;
+ int err = -1;
+
+ err = find_ubi_vol(libubi, name, &dev_num, &vol_id);
+ if (!err)
+ snprintf(part, plen, "/dev/ubiblock%d_%d", dev_num, vol_id);
+
+ return err;
+}
+#endif
+
+static int find_root_dev(char *buf, int len)
+{
+ DIR *d;
+ dev_t root;
+ struct stat s;
+ struct dirent *e;
+
+ if (stat("/", &s))
+ return -1;
+
+ if (!(d = opendir("/dev")))
+ return -1;
+
+ root = s.st_dev;
+
+ while ((e = readdir(d)) != NULL) {
+ snprintf(buf, len, "/dev/%s", e->d_name);
+
+ if (stat(buf, &s) || s.st_rdev != root)
+ continue;
+
+ closedir(d);
+ return 0;
+ }
+
+ closedir(d);
+ return -1;
+}
+
+static int test_fs_support(const char *name)
+{
+ char line[128], *p;
+ int rv = -1;
+ FILE *f;
+
+ if ((f = fopen("/proc/filesystems", "r")) != NULL) {
+ while (fgets(line, sizeof(line), f)) {
+ p = strtok(line, "\t\n");
+
+ if (p && !strcmp(p, "nodev"))
+ p = strtok(NULL, "\t\n");
+
+ if (p && !strcmp(p, name)) {
+ rv = 0;
+ break;
+ }
+ }
+ fclose(f);
+ }
+
+ return rv;
+}
+