1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
|
#!/usr/bin/env python
# -*- coding: utf-8 -*-
# Copyright 2014-2015 Canonical Limited.
#
# This file is part of charm-helpers.
#
# charm-helpers is free software: you can redistribute it and/or modify
# it under the terms of the GNU Lesser General Public License version 3 as
# published by the Free Software Foundation.
#
# charm-helpers is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with charm-helpers. If not, see <http://www.gnu.org/licenses/>.
import io
import os
__author__ = 'Jorge Niedbalski R. <jorge.niedbalski@canonical.com>'
class Fstab(io.FileIO):
"""This class extends file in order to implement a file reader/writer
for file `/etc/fstab`
"""
class Entry(object):
"""Entry class represents a non-comment line on the `/etc/fstab` file
"""
def __init__(self, device, mountpoint, filesystem,
options, d=0, p=0):
self.device = device
self.mountpoint = mountpoint
self.filesystem = filesystem
if not options:
options = "defaults"
self.options = options
self.d = int(d)
self.p = int(p)
def __eq__(self, o):
return str(self) == str(o)
def __str__(self):
return "{} {} {} {} {} {}".format(self.device,
self.mountpoint,
self.filesystem,
self.options,
self.d,
self.p)
DEFAULT_PATH = os.path.join(os.path.sep, 'etc', 'fstab')
def __init__(self, path=None):
if path:
self._path = path
else:
self._path = self.DEFAULT_PATH
super(Fstab, self).__init__(self._path, 'rb+')
def _hydrate_entry(self, line):
# NOTE: use split with no arguments to split on any
# whitespace including tabs
return Fstab.Entry(*filter(
lambda x: x not in ('', None),
line.strip("\n").split()))
@property
def entries(self):
self.seek(0)
for line in self.readlines():
line = line.decode('us-ascii')
try:
if line.strip() and not line.strip().startswith("#"):
yield self._hydrate_entry(line)
except ValueError:
pass
def get_entry_by_attr(self, attr, value):
for entry in self.entries:
e_attr = getattr(entry, attr)
if e_attr == value:
return entry
return None
def add_entry(self, entry):
if self.get_entry_by_attr('device', entry.device):
return False
self.write((str(entry) + '\n').encode('us-ascii'))
self.truncate()
return entry
def remove_entry(self, entry):
self.seek(0)
lines = [l.decode('us-ascii') for l in self.readlines()]
found = False
for index, line in enumerate(lines):
if line.strip() and not line.strip().startswith("#"):
if self._hydrate_entry(line) == entry:
found = True
break
if not found:
return False
lines.remove(line)
self.seek(0)
self.write(''.join(lines).encode('us-ascii'))
self.truncate()
return True
@classmethod
def remove_by_mountpoint(cls, mountpoint, path=None):
fstab = cls(path=path)
entry = fstab.get_entry_by_attr('mountpoint', mountpoint)
if entry:
return fstab.remove_entry(entry)
return False
@classmethod
def add(cls, device, mountpoint, filesystem, options=None, path=None):
return cls(path=path).add_entry(Fstab.Entry(device,
mountpoint, filesystem,
options=options))
|
