src/udev/udevadm-util.c

   1 /* SPDX-License-Identifier: GPL-2.0+ */
   2
   3 #include "path-util.h"
   4 #include "string-util.h"
   5 #include "udevadm-util.h"
   6
   7 struct udev_device *find_device(struct udev *udev,
   8                                 const char *id,
   9                                 const char *prefix) {
  10
  11         assert(id);
  12
  13         if (prefix && !startswith(id, prefix))
  14                 id = strjoina(prefix, id);
  15
  16         if (path_startswith(id, "/dev/")) {
  17                 struct stat statbuf;
  18                 char type;
  19
  20                 if (stat(id, &statbuf) < 0)
  21                         return NULL;
  22
  23                 if (S_ISBLK(statbuf.st_mode))
  24                         type = 'b';
  25                 else if (S_ISCHR(statbuf.st_mode))
  26                         type = 'c';
  27                 else
  28                         return NULL;
  29
  30                 return udev_device_new_from_devnum(udev, type, statbuf.st_rdev);
  31         } else if (path_startswith(id, "/sys/"))
  32                 return udev_device_new_from_syspath(udev, id);
  33         else
  34                 return NULL;
  35 }