libbb/ubi.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Utility routines.
   4  *
   5  * Copyright (C) 2016 Denys Vlasenko
   6  *
   7  * Licensed under GPLv2, see file LICENSE in this source tree.
   8  */
   9 //kbuild:lib-y += ubi.o
  10
  11 #include "libbb.h"
  12
  13 // from ubi-media.h
  14 #define UBI_MAX_VOLUME_NAME 127
  15 #define UBI_MAX_VOLUMES     128
  16
  17 unsigned FAST_FUNC ubi_devnum_from_devname(const char *str)
  18 {
  19         unsigned ubi_devnum;
  20
  21         if (sscanf(str, "/dev/ubi%u", &ubi_devnum) != 1)
  22                 bb_error_msg_and_die("not an UBI device: '%s'", str);
  23         return ubi_devnum;
  24 }
  25
  26 int FAST_FUNC ubi_get_volid_by_name(unsigned ubi_devnum, const char *vol_name)
  27 {
  28         unsigned i;
  29
  30         for (i = 0; i < UBI_MAX_VOLUMES; i++) {
  31                 char buf[UBI_MAX_VOLUME_NAME + 1];
  32                 char fname[sizeof("/sys/class/ubi/ubi%u_%u/name") + 2 * sizeof(int)*3];
  33
  34                 sprintf(fname, "/sys/class/ubi/ubi%u_%u/name", ubi_devnum, i);
  35                 if (open_read_close(fname, buf, sizeof(buf)) <= 0)
  36                         continue;
  37
  38                 buf[UBI_MAX_VOLUME_NAME] = '\0';
  39                 strchrnul(buf, '\n')[0] = '\0';
  40                 if (strcmp(vol_name, buf) == 0)
  41                         return i;
  42         }
  43         bb_error_msg_and_die("volume '%s' not found", vol_name);
  44 }