ceph/src/ceph-volume/ceph_volume/util/system.py

   1 import errno
   2 import os
   3 import pwd
   4 import platform
   5 import uuid
   6 from ceph_volume import process
   7 from . import as_string
   8
   9
  10 # TODO: get these out of here and into a common area for others to consume
  11 if platform.system() == 'FreeBSD':
  12     FREEBSD = True
  13     DEFAULT_FS_TYPE = 'zfs'
  14     PROCDIR = '/compat/linux/proc'
  15     # FreeBSD does not have blockdevices any more
  16     BLOCKDIR = '/dev'
  17     ROOTGROUP = 'wheel'
  18 else:
  19     FREEBSD = False
  20     DEFAULT_FS_TYPE = 'xfs'
  21     PROCDIR = '/proc'
  22     BLOCKDIR = '/sys/block'
  23     ROOTGROUP = 'root'
  24
  25
  26 def generate_uuid():
  27     return str(uuid.uuid4())
  28
  29
  30 def get_ceph_user_ids():
  31     """
  32     Return the id and gid of the ceph user
  33     """
  34     try:
  35         user = pwd.getpwnam('ceph')
  36     except KeyError:
  37         # is this even possible?
  38         raise RuntimeError('"ceph" user is not available in the current system')
  39     return user[2], user[3]
  40
  41
  42 def mkdir_p(path, chown=True):
  43     """
  44     A `mkdir -p` that defaults to chown the path to the ceph user
  45     """
  46     try:
  47         os.mkdir(path)
  48     except OSError as e:
  49         if e.errno == errno.EEXIST:
  50             pass
  51         else:
  52             raise
  53     if chown:
  54         uid, gid = get_ceph_user_ids()
  55         os.chown(path, uid, gid)
  56
  57
  58 def chown(path, recursive=True):
  59     """
  60     ``chown`` a path to the ceph user (uid and guid fetched at runtime)
  61     """
  62     uid, gid = get_ceph_user_ids()
  63     if os.path.islink(path):
  64         path = os.path.realpath(path)
  65     if recursive:
  66         process.run(['chown', '-R', 'ceph:ceph', path])
  67     else:
  68         os.chown(path, uid, gid)
  69
  70
  71 def is_mounted(source, destination=None):
  72     """
  73     Check if the given device is mounted, optionally validating destination.
  74     This relies on absolute path devices, it will ignore non-absolute
  75     entries like::
  76
  77         tmpfs /run tmpfs rw,seclabel,nosuid,nodev,mode=755 0 0
  78
  79     But will parse paths that are absolute like::
  80
  81         /dev/sdc2 /boot xfs rw,attr2,inode64,noquota 0 0
  82
  83     When destination is passed in, it will check that the entry where the
  84     source appears is mounted to where destination defines. This is useful so
  85     that an error message can report that a source is not mounted at an
  86     expected destination.
  87     """
  88     dev = os.path.realpath(source)
  89     with open(PROCDIR + '/mounts', 'rb') as proc_mounts:
  90         for line in proc_mounts:
  91             fields = line.split()
  92             if len(fields) < 3:
  93                 continue
  94             mounted_device = fields[0]
  95             mounted_path = fields[1]
  96             if os.path.isabs(mounted_device) and os.path.exists(mounted_device):
  97                 mounted_device = os.path.realpath(mounted_device)
  98                 if as_string(mounted_device) == dev:
  99                     if destination:
 100                         destination = os.path.realpath(destination)
 101                         return destination == as_string(os.path.realpath(mounted_path))
 102                     else:
 103                         return True
 104     return False