src/udev/udevadm-util.c

   1 /*
   2  * Copyright (C) 2008-2009 Kay Sievers <kay@vrfy.org>
   3  *
   4  * This program is free software: you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation, either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 #include "udevadm-util.h"
  19
  20 struct udev_device *find_device(struct udev *udev,
  21                                 const char *id,
  22                                 const char *prefix) {
  23
  24         assert(udev);
  25         assert(id);
  26
  27         if (prefix && !startswith(id, prefix))
  28                 id = strappenda(prefix, id);
  29
  30         if (startswith(id, "/dev/")) {
  31                 struct stat statbuf;
  32                 char type;
  33
  34                 if (stat(id, &statbuf) < 0)
  35                         return NULL;
  36
  37                 if (S_ISBLK(statbuf.st_mode))
  38                         type = 'b';
  39                 else if (S_ISCHR(statbuf.st_mode))
  40                         type = 'c';
  41                 else
  42                         return NULL;
  43
  44                 return udev_device_new_from_devnum(udev, type, statbuf.st_rdev);
  45         } else if (startswith(id, "/sys/"))
  46                 return udev_device_new_from_syspath(udev, id);
  47         else
  48                 return NULL;
  49 }