src/libsystemd/sd-device/device-util.c

   1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
   2
   3 #include "device-private.h"
   4 #include "device-util.h"
   5 #include "devnum-util.h"
   6 #include "fd-util.h"
   7 #include "string-util.h"
   8
   9 int devname_from_devnum(mode_t mode, dev_t devnum, char **ret) {
  10         _cleanup_(sd_device_unrefp) sd_device *dev = NULL;
  11         _cleanup_free_ char *s = NULL;
  12         const char *devname;
  13         int r;
  14
  15         assert(ret);
  16
  17         if (major(devnum) == 0 && minor(devnum) == 0)
  18                 return device_path_make_inaccessible(mode, ret);
  19
  20         r = device_new_from_mode_and_devnum(&dev, mode, devnum);
  21         if (r < 0)
  22                 return r;
  23
  24         r = sd_device_get_devname(dev, &devname);
  25         if (r < 0)
  26                 return r;
  27
  28         s = strdup(devname);
  29         if (!s)
  30                 return -ENOMEM;
  31
  32         *ret = TAKE_PTR(s);
  33         return 0;
  34 }
  35
  36 int device_open_from_devnum(mode_t mode, dev_t devnum, int flags, char **ret) {
  37         _cleanup_(sd_device_unrefp) sd_device *dev = NULL;
  38         _cleanup_close_ int fd = -EBADF;
  39         int r;
  40
  41         r = device_new_from_mode_and_devnum(&dev, mode, devnum);
  42         if (r < 0)
  43                 return r;
  44
  45         fd = sd_device_open(dev, flags);
  46         if (fd < 0)
  47                 return fd;
  48
  49         if (ret) {
  50                 const char *devname;
  51                 char *s;
  52
  53                 r = sd_device_get_devname(dev, &devname);
  54                 if (r < 0)
  55                         return r;
  56
  57                 s = strdup(devname);
  58                 if (!s)
  59                         return -ENOMEM;
  60
  61                 *ret = s;
  62         }
  63
  64         return TAKE_FD(fd);
  65 }