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1 | 3865ca48 | Michael Hanselmann | #
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2 | 3865ca48 | Michael Hanselmann | #
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3 | 3865ca48 | Michael Hanselmann | |
4 | 5ae4945a | Iustin Pop | # Copyright (C) 2006, 2007, 2010, 2011, 2012 Google Inc.
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5 | 3865ca48 | Michael Hanselmann | #
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6 | 3865ca48 | Michael Hanselmann | # This program is free software; you can redistribute it and/or modify
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7 | 3865ca48 | Michael Hanselmann | # it under the terms of the GNU General Public License as published by
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8 | 3865ca48 | Michael Hanselmann | # the Free Software Foundation; either version 2 of the License, or
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9 | 3865ca48 | Michael Hanselmann | # (at your option) any later version.
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10 | 3865ca48 | Michael Hanselmann | #
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11 | 3865ca48 | Michael Hanselmann | # This program is distributed in the hope that it will be useful, but
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12 | 3865ca48 | Michael Hanselmann | # WITHOUT ANY WARRANTY; without even the implied warranty of
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13 | 3865ca48 | Michael Hanselmann | # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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14 | 3865ca48 | Michael Hanselmann | # General Public License for more details.
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15 | 3865ca48 | Michael Hanselmann | #
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16 | 3865ca48 | Michael Hanselmann | # You should have received a copy of the GNU General Public License
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17 | 3865ca48 | Michael Hanselmann | # along with this program; if not, write to the Free Software
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18 | 3865ca48 | Michael Hanselmann | # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
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19 | 3865ca48 | Michael Hanselmann | # 02110-1301, USA.
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20 | 3865ca48 | Michael Hanselmann | |
21 | 3865ca48 | Michael Hanselmann | """Utility functions for I/O.
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22 | 3865ca48 | Michael Hanselmann |
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23 | 3865ca48 | Michael Hanselmann | """
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24 | 3865ca48 | Michael Hanselmann | |
25 | 3865ca48 | Michael Hanselmann | import os |
26 | 3865ca48 | Michael Hanselmann | import logging |
27 | 3865ca48 | Michael Hanselmann | import shutil |
28 | 3865ca48 | Michael Hanselmann | import tempfile |
29 | 3865ca48 | Michael Hanselmann | import errno |
30 | 3865ca48 | Michael Hanselmann | import time |
31 | b81b3c96 | René Nussbaumer | import stat |
32 | 3865ca48 | Michael Hanselmann | |
33 | 3865ca48 | Michael Hanselmann | from ganeti import errors |
34 | 3865ca48 | Michael Hanselmann | from ganeti import constants |
35 | 3865ca48 | Michael Hanselmann | from ganeti.utils import filelock |
36 | 3865ca48 | Michael Hanselmann | |
37 | 3865ca48 | Michael Hanselmann | |
38 | 90e234a6 | Michael Hanselmann | #: Path generating random UUID
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39 | 90e234a6 | Michael Hanselmann | _RANDOM_UUID_FILE = "/proc/sys/kernel/random/uuid"
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40 | 90e234a6 | Michael Hanselmann | |
41 | 2dbc6857 | Michael Hanselmann | #: Directory used by fsck(8) to store recovered data, usually at a file
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42 | 2dbc6857 | Michael Hanselmann | #: system's root directory
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43 | 2dbc6857 | Michael Hanselmann | _LOST_AND_FOUND = "lost+found"
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44 | 2dbc6857 | Michael Hanselmann | |
45 | c47eddb8 | Bernardo Dal Seno | # Possible values for keep_perms in WriteFile()
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46 | c47eddb8 | Bernardo Dal Seno | KP_NEVER = 0
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47 | c47eddb8 | Bernardo Dal Seno | KP_ALWAYS = 1
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48 | c47eddb8 | Bernardo Dal Seno | KP_IF_EXISTS = 2
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49 | c47eddb8 | Bernardo Dal Seno | |
50 | c47eddb8 | Bernardo Dal Seno | KEEP_PERMS_VALUES = [ |
51 | c47eddb8 | Bernardo Dal Seno | KP_NEVER, |
52 | c47eddb8 | Bernardo Dal Seno | KP_ALWAYS, |
53 | c47eddb8 | Bernardo Dal Seno | KP_IF_EXISTS, |
54 | c47eddb8 | Bernardo Dal Seno | ] |
55 | c47eddb8 | Bernardo Dal Seno | |
56 | 90e234a6 | Michael Hanselmann | |
57 | eb93b673 | Guido Trotter | def ErrnoOrStr(err): |
58 | eb93b673 | Guido Trotter | """Format an EnvironmentError exception.
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59 | eb93b673 | Guido Trotter |
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60 | eb93b673 | Guido Trotter | If the L{err} argument has an errno attribute, it will be looked up
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61 | eb93b673 | Guido Trotter | and converted into a textual C{E...} description. Otherwise the
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62 | eb93b673 | Guido Trotter | string representation of the error will be returned.
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63 | eb93b673 | Guido Trotter |
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64 | eb93b673 | Guido Trotter | @type err: L{EnvironmentError}
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65 | eb93b673 | Guido Trotter | @param err: the exception to format
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66 | eb93b673 | Guido Trotter |
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67 | eb93b673 | Guido Trotter | """
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68 | eb93b673 | Guido Trotter | if hasattr(err, "errno"): |
69 | eb93b673 | Guido Trotter | detail = errno.errorcode[err.errno] |
70 | eb93b673 | Guido Trotter | else:
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71 | eb93b673 | Guido Trotter | detail = str(err)
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72 | eb93b673 | Guido Trotter | return detail
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73 | eb93b673 | Guido Trotter | |
74 | eb93b673 | Guido Trotter | |
75 | 2635bb04 | Michael Hanselmann | class FileStatHelper: |
76 | 2635bb04 | Michael Hanselmann | """Helper to store file handle's C{fstat}.
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77 | 2635bb04 | Michael Hanselmann |
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78 | 2635bb04 | Michael Hanselmann | Useful in combination with L{ReadFile}'s C{preread} parameter.
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79 | 2635bb04 | Michael Hanselmann |
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80 | 2635bb04 | Michael Hanselmann | """
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81 | 2635bb04 | Michael Hanselmann | def __init__(self): |
82 | 2635bb04 | Michael Hanselmann | """Initializes this class.
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83 | 2635bb04 | Michael Hanselmann |
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84 | 2635bb04 | Michael Hanselmann | """
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85 | 2635bb04 | Michael Hanselmann | self.st = None |
86 | 2635bb04 | Michael Hanselmann | |
87 | 2635bb04 | Michael Hanselmann | def __call__(self, fh): |
88 | 2635bb04 | Michael Hanselmann | """Calls C{fstat} on file handle.
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89 | 2635bb04 | Michael Hanselmann |
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90 | 2635bb04 | Michael Hanselmann | """
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91 | 2635bb04 | Michael Hanselmann | self.st = os.fstat(fh.fileno())
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92 | 2635bb04 | Michael Hanselmann | |
93 | 2635bb04 | Michael Hanselmann | |
94 | 0e5084ee | Michael Hanselmann | def ReadFile(file_name, size=-1, preread=None): |
95 | 3865ca48 | Michael Hanselmann | """Reads a file.
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96 | 3865ca48 | Michael Hanselmann |
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97 | 3865ca48 | Michael Hanselmann | @type size: int
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98 | 3865ca48 | Michael Hanselmann | @param size: Read at most size bytes (if negative, entire file)
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99 | 0e5084ee | Michael Hanselmann | @type preread: callable receiving file handle as single parameter
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100 | 0e5084ee | Michael Hanselmann | @param preread: Function called before file is read
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101 | 3865ca48 | Michael Hanselmann | @rtype: str
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102 | 3865ca48 | Michael Hanselmann | @return: the (possibly partial) content of the file
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103 | 3865ca48 | Michael Hanselmann |
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104 | 3865ca48 | Michael Hanselmann | """
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105 | 3865ca48 | Michael Hanselmann | f = open(file_name, "r") |
106 | 3865ca48 | Michael Hanselmann | try:
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107 | 0e5084ee | Michael Hanselmann | if preread:
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108 | 0e5084ee | Michael Hanselmann | preread(f) |
109 | 0e5084ee | Michael Hanselmann | |
110 | 3865ca48 | Michael Hanselmann | return f.read(size)
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111 | 3865ca48 | Michael Hanselmann | finally:
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112 | 3865ca48 | Michael Hanselmann | f.close() |
113 | 3865ca48 | Michael Hanselmann | |
114 | 3865ca48 | Michael Hanselmann | |
115 | 3865ca48 | Michael Hanselmann | def WriteFile(file_name, fn=None, data=None, |
116 | 3865ca48 | Michael Hanselmann | mode=None, uid=-1, gid=-1, |
117 | 3865ca48 | Michael Hanselmann | atime=None, mtime=None, close=True, |
118 | 3865ca48 | Michael Hanselmann | dry_run=False, backup=False, |
119 | c47eddb8 | Bernardo Dal Seno | prewrite=None, postwrite=None, keep_perms=KP_NEVER): |
120 | 3865ca48 | Michael Hanselmann | """(Over)write a file atomically.
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121 | 3865ca48 | Michael Hanselmann |
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122 | 3865ca48 | Michael Hanselmann | The file_name and either fn (a function taking one argument, the
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123 | 3865ca48 | Michael Hanselmann | file descriptor, and which should write the data to it) or data (the
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124 | 3865ca48 | Michael Hanselmann | contents of the file) must be passed. The other arguments are
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125 | 3865ca48 | Michael Hanselmann | optional and allow setting the file mode, owner and group, and the
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126 | 3865ca48 | Michael Hanselmann | mtime/atime of the file.
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127 | 3865ca48 | Michael Hanselmann |
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128 | 3865ca48 | Michael Hanselmann | If the function doesn't raise an exception, it has succeeded and the
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129 | 3865ca48 | Michael Hanselmann | target file has the new contents. If the function has raised an
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130 | 3865ca48 | Michael Hanselmann | exception, an existing target file should be unmodified and the
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131 | 3865ca48 | Michael Hanselmann | temporary file should be removed.
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132 | 3865ca48 | Michael Hanselmann |
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133 | 3865ca48 | Michael Hanselmann | @type file_name: str
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134 | 3865ca48 | Michael Hanselmann | @param file_name: the target filename
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135 | 3865ca48 | Michael Hanselmann | @type fn: callable
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136 | 3865ca48 | Michael Hanselmann | @param fn: content writing function, called with
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137 | 3865ca48 | Michael Hanselmann | file descriptor as parameter
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138 | 3865ca48 | Michael Hanselmann | @type data: str
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139 | 3865ca48 | Michael Hanselmann | @param data: contents of the file
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140 | 3865ca48 | Michael Hanselmann | @type mode: int
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141 | 3865ca48 | Michael Hanselmann | @param mode: file mode
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142 | 3865ca48 | Michael Hanselmann | @type uid: int
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143 | 3865ca48 | Michael Hanselmann | @param uid: the owner of the file
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144 | 3865ca48 | Michael Hanselmann | @type gid: int
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145 | 3865ca48 | Michael Hanselmann | @param gid: the group of the file
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146 | 3865ca48 | Michael Hanselmann | @type atime: int
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147 | 3865ca48 | Michael Hanselmann | @param atime: a custom access time to be set on the file
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148 | 3865ca48 | Michael Hanselmann | @type mtime: int
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149 | 3865ca48 | Michael Hanselmann | @param mtime: a custom modification time to be set on the file
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150 | 3865ca48 | Michael Hanselmann | @type close: boolean
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151 | 3865ca48 | Michael Hanselmann | @param close: whether to close file after writing it
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152 | 3865ca48 | Michael Hanselmann | @type prewrite: callable
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153 | 3865ca48 | Michael Hanselmann | @param prewrite: function to be called before writing content
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154 | 3865ca48 | Michael Hanselmann | @type postwrite: callable
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155 | 3865ca48 | Michael Hanselmann | @param postwrite: function to be called after writing content
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156 | c47eddb8 | Bernardo Dal Seno | @type keep_perms: members of L{KEEP_PERMS_VALUES}
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157 | c47eddb8 | Bernardo Dal Seno | @param keep_perms: if L{KP_NEVER} (default), owner, group, and mode are
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158 | c47eddb8 | Bernardo Dal Seno | taken from the other parameters; if L{KP_ALWAYS}, owner, group, and
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159 | c47eddb8 | Bernardo Dal Seno | mode are copied from the existing file; if L{KP_IF_EXISTS}, owner,
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160 | c47eddb8 | Bernardo Dal Seno | group, and mode are taken from the file, and if the file doesn't
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161 | c47eddb8 | Bernardo Dal Seno | exist, they are taken from the other parameters. It is an error to
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162 | c47eddb8 | Bernardo Dal Seno | pass L{KP_ALWAYS} when the file doesn't exist or when C{uid}, C{gid},
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163 | c47eddb8 | Bernardo Dal Seno | or C{mode} are set to non-default values.
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164 | 3865ca48 | Michael Hanselmann |
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165 | 3865ca48 | Michael Hanselmann | @rtype: None or int
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166 | 3865ca48 | Michael Hanselmann | @return: None if the 'close' parameter evaluates to True,
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167 | 3865ca48 | Michael Hanselmann | otherwise the file descriptor
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168 | 3865ca48 | Michael Hanselmann |
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169 | 3865ca48 | Michael Hanselmann | @raise errors.ProgrammerError: if any of the arguments are not valid
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170 | 3865ca48 | Michael Hanselmann |
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171 | 3865ca48 | Michael Hanselmann | """
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172 | 3865ca48 | Michael Hanselmann | if not os.path.isabs(file_name): |
173 | 3865ca48 | Michael Hanselmann | raise errors.ProgrammerError("Path passed to WriteFile is not" |
174 | 3865ca48 | Michael Hanselmann | " absolute: '%s'" % file_name)
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175 | 3865ca48 | Michael Hanselmann | |
176 | 3865ca48 | Michael Hanselmann | if [fn, data].count(None) != 1: |
177 | 3865ca48 | Michael Hanselmann | raise errors.ProgrammerError("fn or data required") |
178 | 3865ca48 | Michael Hanselmann | |
179 | 3865ca48 | Michael Hanselmann | if [atime, mtime].count(None) == 1: |
180 | 3865ca48 | Michael Hanselmann | raise errors.ProgrammerError("Both atime and mtime must be either" |
181 | 3865ca48 | Michael Hanselmann | " set or None")
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182 | 3865ca48 | Michael Hanselmann | |
183 | c47eddb8 | Bernardo Dal Seno | if not keep_perms in KEEP_PERMS_VALUES: |
184 | c47eddb8 | Bernardo Dal Seno | raise errors.ProgrammerError("Invalid value for keep_perms: %s" % |
185 | c47eddb8 | Bernardo Dal Seno | keep_perms) |
186 | c47eddb8 | Bernardo Dal Seno | if keep_perms == KP_ALWAYS and (uid != -1 or gid != -1 or mode is not None): |
187 | c47eddb8 | Bernardo Dal Seno | raise errors.ProgrammerError("When keep_perms==KP_ALWAYS, 'uid', 'gid'," |
188 | c47eddb8 | Bernardo Dal Seno | " and 'mode' cannot be set")
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189 | c47eddb8 | Bernardo Dal Seno | |
190 | 3865ca48 | Michael Hanselmann | if backup and not dry_run and os.path.isfile(file_name): |
191 | 3865ca48 | Michael Hanselmann | CreateBackup(file_name) |
192 | 3865ca48 | Michael Hanselmann | |
193 | c47eddb8 | Bernardo Dal Seno | if keep_perms == KP_ALWAYS or keep_perms == KP_IF_EXISTS: |
194 | c47eddb8 | Bernardo Dal Seno | # os.stat() raises an exception if the file doesn't exist
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195 | c47eddb8 | Bernardo Dal Seno | try:
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196 | c47eddb8 | Bernardo Dal Seno | file_stat = os.stat(file_name) |
197 | c47eddb8 | Bernardo Dal Seno | mode = stat.S_IMODE(file_stat.st_mode) |
198 | c47eddb8 | Bernardo Dal Seno | uid = file_stat.st_uid |
199 | c47eddb8 | Bernardo Dal Seno | gid = file_stat.st_gid |
200 | c47eddb8 | Bernardo Dal Seno | except OSError: |
201 | c47eddb8 | Bernardo Dal Seno | if keep_perms == KP_ALWAYS:
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202 | c47eddb8 | Bernardo Dal Seno | raise
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203 | c47eddb8 | Bernardo Dal Seno | # else: if keeep_perms == KP_IF_EXISTS it's ok if the file doesn't exist
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204 | c47eddb8 | Bernardo Dal Seno | |
205 | a9d68e40 | Michael Hanselmann | # Whether temporary file needs to be removed (e.g. if any error occurs)
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206 | 3865ca48 | Michael Hanselmann | do_remove = True
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207 | a9d68e40 | Michael Hanselmann | |
208 | a9d68e40 | Michael Hanselmann | # Function result
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209 | a9d68e40 | Michael Hanselmann | result = None
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210 | a9d68e40 | Michael Hanselmann | |
211 | a9d68e40 | Michael Hanselmann | (dir_name, base_name) = os.path.split(file_name) |
212 | a9d68e40 | Michael Hanselmann | (fd, new_name) = tempfile.mkstemp(suffix=".new", prefix=base_name,
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213 | a9d68e40 | Michael Hanselmann | dir=dir_name) |
214 | 3865ca48 | Michael Hanselmann | try:
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215 | a9d68e40 | Michael Hanselmann | try:
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216 | a9d68e40 | Michael Hanselmann | if uid != -1 or gid != -1: |
217 | a9d68e40 | Michael Hanselmann | os.chown(new_name, uid, gid) |
218 | a9d68e40 | Michael Hanselmann | if mode:
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219 | a9d68e40 | Michael Hanselmann | os.chmod(new_name, mode) |
220 | a9d68e40 | Michael Hanselmann | if callable(prewrite): |
221 | a9d68e40 | Michael Hanselmann | prewrite(fd) |
222 | a9d68e40 | Michael Hanselmann | if data is not None: |
223 | 1d39e245 | Iustin Pop | if isinstance(data, unicode): |
224 | 1d39e245 | Iustin Pop | data = data.encode() |
225 | 1d39e245 | Iustin Pop | assert isinstance(data, str) |
226 | 437c3e77 | Iustin Pop | to_write = len(data)
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227 | 437c3e77 | Iustin Pop | offset = 0
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228 | 437c3e77 | Iustin Pop | while offset < to_write:
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229 | 437c3e77 | Iustin Pop | written = os.write(fd, buffer(data, offset))
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230 | 437c3e77 | Iustin Pop | assert written >= 0 |
231 | 1d39e245 | Iustin Pop | assert written <= to_write - offset
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232 | 437c3e77 | Iustin Pop | offset += written |
233 | 437c3e77 | Iustin Pop | assert offset == to_write
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234 | a9d68e40 | Michael Hanselmann | else:
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235 | a9d68e40 | Michael Hanselmann | fn(fd) |
236 | a9d68e40 | Michael Hanselmann | if callable(postwrite): |
237 | a9d68e40 | Michael Hanselmann | postwrite(fd) |
238 | a9d68e40 | Michael Hanselmann | os.fsync(fd) |
239 | a9d68e40 | Michael Hanselmann | if atime is not None and mtime is not None: |
240 | a9d68e40 | Michael Hanselmann | os.utime(new_name, (atime, mtime)) |
241 | a9d68e40 | Michael Hanselmann | finally:
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242 | a9d68e40 | Michael Hanselmann | # Close file unless the file descriptor should be returned
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243 | a9d68e40 | Michael Hanselmann | if close:
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244 | a9d68e40 | Michael Hanselmann | os.close(fd) |
245 | a9d68e40 | Michael Hanselmann | else:
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246 | a9d68e40 | Michael Hanselmann | result = fd |
247 | a9d68e40 | Michael Hanselmann | |
248 | a9d68e40 | Michael Hanselmann | # Rename file to destination name
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249 | 3865ca48 | Michael Hanselmann | if not dry_run: |
250 | 3865ca48 | Michael Hanselmann | os.rename(new_name, file_name) |
251 | a9d68e40 | Michael Hanselmann | # Successful, no need to remove anymore
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252 | 3865ca48 | Michael Hanselmann | do_remove = False
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253 | 3865ca48 | Michael Hanselmann | finally:
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254 | 3865ca48 | Michael Hanselmann | if do_remove:
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255 | 3865ca48 | Michael Hanselmann | RemoveFile(new_name) |
256 | 3865ca48 | Michael Hanselmann | |
257 | 3865ca48 | Michael Hanselmann | return result
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258 | 3865ca48 | Michael Hanselmann | |
259 | 3865ca48 | Michael Hanselmann | |
260 | 3865ca48 | Michael Hanselmann | def GetFileID(path=None, fd=None): |
261 | 3865ca48 | Michael Hanselmann | """Returns the file 'id', i.e. the dev/inode and mtime information.
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262 | 3865ca48 | Michael Hanselmann |
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263 | 3865ca48 | Michael Hanselmann | Either the path to the file or the fd must be given.
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264 | 3865ca48 | Michael Hanselmann |
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265 | 3865ca48 | Michael Hanselmann | @param path: the file path
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266 | 3865ca48 | Michael Hanselmann | @param fd: a file descriptor
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267 | 3865ca48 | Michael Hanselmann | @return: a tuple of (device number, inode number, mtime)
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268 | 3865ca48 | Michael Hanselmann |
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269 | 3865ca48 | Michael Hanselmann | """
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270 | 3865ca48 | Michael Hanselmann | if [path, fd].count(None) != 1: |
271 | 3865ca48 | Michael Hanselmann | raise errors.ProgrammerError("One and only one of fd/path must be given") |
272 | 3865ca48 | Michael Hanselmann | |
273 | 3865ca48 | Michael Hanselmann | if fd is None: |
274 | 3865ca48 | Michael Hanselmann | st = os.stat(path) |
275 | 3865ca48 | Michael Hanselmann | else:
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276 | 3865ca48 | Michael Hanselmann | st = os.fstat(fd) |
277 | 3865ca48 | Michael Hanselmann | |
278 | 3865ca48 | Michael Hanselmann | return (st.st_dev, st.st_ino, st.st_mtime)
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279 | 3865ca48 | Michael Hanselmann | |
280 | 3865ca48 | Michael Hanselmann | |
281 | 3865ca48 | Michael Hanselmann | def VerifyFileID(fi_disk, fi_ours): |
282 | 3865ca48 | Michael Hanselmann | """Verifies that two file IDs are matching.
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283 | 3865ca48 | Michael Hanselmann |
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284 | 3865ca48 | Michael Hanselmann | Differences in the inode/device are not accepted, but and older
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285 | 3865ca48 | Michael Hanselmann | timestamp for fi_disk is accepted.
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286 | 3865ca48 | Michael Hanselmann |
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287 | 3865ca48 | Michael Hanselmann | @param fi_disk: tuple (dev, inode, mtime) representing the actual
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288 | 3865ca48 | Michael Hanselmann | file data
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289 | 3865ca48 | Michael Hanselmann | @param fi_ours: tuple (dev, inode, mtime) representing the last
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290 | 3865ca48 | Michael Hanselmann | written file data
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291 | 3865ca48 | Michael Hanselmann | @rtype: boolean
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292 | 3865ca48 | Michael Hanselmann |
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293 | 3865ca48 | Michael Hanselmann | """
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294 | 3865ca48 | Michael Hanselmann | (d1, i1, m1) = fi_disk |
295 | 3865ca48 | Michael Hanselmann | (d2, i2, m2) = fi_ours |
296 | 3865ca48 | Michael Hanselmann | |
297 | 3865ca48 | Michael Hanselmann | return (d1, i1) == (d2, i2) and m1 <= m2 |
298 | 3865ca48 | Michael Hanselmann | |
299 | 3865ca48 | Michael Hanselmann | |
300 | 3865ca48 | Michael Hanselmann | def SafeWriteFile(file_name, file_id, **kwargs): |
301 | 3865ca48 | Michael Hanselmann | """Wraper over L{WriteFile} that locks the target file.
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302 | 3865ca48 | Michael Hanselmann |
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303 | 3865ca48 | Michael Hanselmann | By keeping the target file locked during WriteFile, we ensure that
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304 | 3865ca48 | Michael Hanselmann | cooperating writers will safely serialise access to the file.
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305 | 3865ca48 | Michael Hanselmann |
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306 | 3865ca48 | Michael Hanselmann | @type file_name: str
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307 | 3865ca48 | Michael Hanselmann | @param file_name: the target filename
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308 | 3865ca48 | Michael Hanselmann | @type file_id: tuple
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309 | 3865ca48 | Michael Hanselmann | @param file_id: a result from L{GetFileID}
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310 | 3865ca48 | Michael Hanselmann |
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311 | 3865ca48 | Michael Hanselmann | """
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312 | 3865ca48 | Michael Hanselmann | fd = os.open(file_name, os.O_RDONLY | os.O_CREAT) |
313 | 3865ca48 | Michael Hanselmann | try:
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314 | 3865ca48 | Michael Hanselmann | filelock.LockFile(fd) |
315 | 3865ca48 | Michael Hanselmann | if file_id is not None: |
316 | 3865ca48 | Michael Hanselmann | disk_id = GetFileID(fd=fd) |
317 | 3865ca48 | Michael Hanselmann | if not VerifyFileID(disk_id, file_id): |
318 | 3865ca48 | Michael Hanselmann | raise errors.LockError("Cannot overwrite file %s, it has been modified" |
319 | 3865ca48 | Michael Hanselmann | " since last written" % file_name)
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320 | 3865ca48 | Michael Hanselmann | return WriteFile(file_name, **kwargs)
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321 | 3865ca48 | Michael Hanselmann | finally:
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322 | 3865ca48 | Michael Hanselmann | os.close(fd) |
323 | 3865ca48 | Michael Hanselmann | |
324 | 3865ca48 | Michael Hanselmann | |
325 | 3865ca48 | Michael Hanselmann | def ReadOneLineFile(file_name, strict=False): |
326 | 3865ca48 | Michael Hanselmann | """Return the first non-empty line from a file.
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327 | 3865ca48 | Michael Hanselmann |
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328 | 3865ca48 | Michael Hanselmann | @type strict: boolean
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329 | 3865ca48 | Michael Hanselmann | @param strict: if True, abort if the file has more than one
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330 | 3865ca48 | Michael Hanselmann | non-empty line
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331 | 3865ca48 | Michael Hanselmann |
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332 | 3865ca48 | Michael Hanselmann | """
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333 | 3865ca48 | Michael Hanselmann | file_lines = ReadFile(file_name).splitlines() |
334 | 3865ca48 | Michael Hanselmann | full_lines = filter(bool, file_lines) |
335 | 3865ca48 | Michael Hanselmann | if not file_lines or not full_lines: |
336 | 3865ca48 | Michael Hanselmann | raise errors.GenericError("No data in one-liner file %s" % file_name) |
337 | 3865ca48 | Michael Hanselmann | elif strict and len(full_lines) > 1: |
338 | 3865ca48 | Michael Hanselmann | raise errors.GenericError("Too many lines in one-liner file %s" % |
339 | 3865ca48 | Michael Hanselmann | file_name) |
340 | 3865ca48 | Michael Hanselmann | return full_lines[0] |
341 | 3865ca48 | Michael Hanselmann | |
342 | 3865ca48 | Michael Hanselmann | |
343 | 3865ca48 | Michael Hanselmann | def RemoveFile(filename): |
344 | 3865ca48 | Michael Hanselmann | """Remove a file ignoring some errors.
|
345 | 3865ca48 | Michael Hanselmann |
|
346 | 3865ca48 | Michael Hanselmann | Remove a file, ignoring non-existing ones or directories. Other
|
347 | 3865ca48 | Michael Hanselmann | errors are passed.
|
348 | 3865ca48 | Michael Hanselmann |
|
349 | 3865ca48 | Michael Hanselmann | @type filename: str
|
350 | 3865ca48 | Michael Hanselmann | @param filename: the file to be removed
|
351 | 3865ca48 | Michael Hanselmann |
|
352 | 3865ca48 | Michael Hanselmann | """
|
353 | 3865ca48 | Michael Hanselmann | try:
|
354 | 3865ca48 | Michael Hanselmann | os.unlink(filename) |
355 | 3865ca48 | Michael Hanselmann | except OSError, err: |
356 | 3865ca48 | Michael Hanselmann | if err.errno not in (errno.ENOENT, errno.EISDIR): |
357 | 3865ca48 | Michael Hanselmann | raise
|
358 | 3865ca48 | Michael Hanselmann | |
359 | 3865ca48 | Michael Hanselmann | |
360 | 3865ca48 | Michael Hanselmann | def RemoveDir(dirname): |
361 | 3865ca48 | Michael Hanselmann | """Remove an empty directory.
|
362 | 3865ca48 | Michael Hanselmann |
|
363 | 3865ca48 | Michael Hanselmann | Remove a directory, ignoring non-existing ones.
|
364 | 3865ca48 | Michael Hanselmann | Other errors are passed. This includes the case,
|
365 | 3865ca48 | Michael Hanselmann | where the directory is not empty, so it can't be removed.
|
366 | 3865ca48 | Michael Hanselmann |
|
367 | 3865ca48 | Michael Hanselmann | @type dirname: str
|
368 | 3865ca48 | Michael Hanselmann | @param dirname: the empty directory to be removed
|
369 | 3865ca48 | Michael Hanselmann |
|
370 | 3865ca48 | Michael Hanselmann | """
|
371 | 3865ca48 | Michael Hanselmann | try:
|
372 | 3865ca48 | Michael Hanselmann | os.rmdir(dirname) |
373 | 3865ca48 | Michael Hanselmann | except OSError, err: |
374 | 3865ca48 | Michael Hanselmann | if err.errno != errno.ENOENT:
|
375 | 3865ca48 | Michael Hanselmann | raise
|
376 | 3865ca48 | Michael Hanselmann | |
377 | 3865ca48 | Michael Hanselmann | |
378 | 8e5a705d | René Nussbaumer | def RenameFile(old, new, mkdir=False, mkdir_mode=0750, dir_uid=None, |
379 | 8e5a705d | René Nussbaumer | dir_gid=None):
|
380 | 3865ca48 | Michael Hanselmann | """Renames a file.
|
381 | 3865ca48 | Michael Hanselmann |
|
382 | 9c2b3a70 | René Nussbaumer | This just creates the very least directory if it does not exist and C{mkdir}
|
383 | 9c2b3a70 | René Nussbaumer | is set to true.
|
384 | 9c2b3a70 | René Nussbaumer |
|
385 | 3865ca48 | Michael Hanselmann | @type old: string
|
386 | 3865ca48 | Michael Hanselmann | @param old: Original path
|
387 | 3865ca48 | Michael Hanselmann | @type new: string
|
388 | 3865ca48 | Michael Hanselmann | @param new: New path
|
389 | 3865ca48 | Michael Hanselmann | @type mkdir: bool
|
390 | 3865ca48 | Michael Hanselmann | @param mkdir: Whether to create target directory if it doesn't exist
|
391 | 3865ca48 | Michael Hanselmann | @type mkdir_mode: int
|
392 | 3865ca48 | Michael Hanselmann | @param mkdir_mode: Mode for newly created directories
|
393 | 8e5a705d | René Nussbaumer | @type dir_uid: int
|
394 | 8e5a705d | René Nussbaumer | @param dir_uid: The uid for the (if fresh created) dir
|
395 | 8e5a705d | René Nussbaumer | @type dir_gid: int
|
396 | 8e5a705d | René Nussbaumer | @param dir_gid: The gid for the (if fresh created) dir
|
397 | 3865ca48 | Michael Hanselmann |
|
398 | 3865ca48 | Michael Hanselmann | """
|
399 | 3865ca48 | Michael Hanselmann | try:
|
400 | 3865ca48 | Michael Hanselmann | return os.rename(old, new)
|
401 | 3865ca48 | Michael Hanselmann | except OSError, err: |
402 | 3865ca48 | Michael Hanselmann | # In at least one use case of this function, the job queue, directory
|
403 | 3865ca48 | Michael Hanselmann | # creation is very rare. Checking for the directory before renaming is not
|
404 | 3865ca48 | Michael Hanselmann | # as efficient.
|
405 | 3865ca48 | Michael Hanselmann | if mkdir and err.errno == errno.ENOENT: |
406 | 3865ca48 | Michael Hanselmann | # Create directory and try again
|
407 | 8e5a705d | René Nussbaumer | dir_path = os.path.dirname(new) |
408 | 9c2b3a70 | René Nussbaumer | MakeDirWithPerm(dir_path, mkdir_mode, dir_uid, dir_gid) |
409 | 3865ca48 | Michael Hanselmann | |
410 | 3865ca48 | Michael Hanselmann | return os.rename(old, new)
|
411 | 3865ca48 | Michael Hanselmann | |
412 | 3865ca48 | Michael Hanselmann | raise
|
413 | 3865ca48 | Michael Hanselmann | |
414 | 3865ca48 | Michael Hanselmann | |
415 | 9c2b3a70 | René Nussbaumer | def EnforcePermission(path, mode, uid=None, gid=None, must_exist=True, |
416 | b81b3c96 | René Nussbaumer | _chmod_fn=os.chmod, _chown_fn=os.chown, _stat_fn=os.stat): |
417 | b81b3c96 | René Nussbaumer | """Enforces that given path has given permissions.
|
418 | b81b3c96 | René Nussbaumer |
|
419 | b81b3c96 | René Nussbaumer | @param path: The path to the file
|
420 | b81b3c96 | René Nussbaumer | @param mode: The mode of the file
|
421 | b81b3c96 | René Nussbaumer | @param uid: The uid of the owner of this file
|
422 | b81b3c96 | René Nussbaumer | @param gid: The gid of the owner of this file
|
423 | b81b3c96 | René Nussbaumer | @param must_exist: Specifies if non-existance of path will be an error
|
424 | b81b3c96 | René Nussbaumer | @param _chmod_fn: chmod function to use (unittest only)
|
425 | b81b3c96 | René Nussbaumer | @param _chown_fn: chown function to use (unittest only)
|
426 | b81b3c96 | René Nussbaumer |
|
427 | b81b3c96 | René Nussbaumer | """
|
428 | b81b3c96 | René Nussbaumer | logging.debug("Checking %s", path)
|
429 | 9c2b3a70 | René Nussbaumer | |
430 | 9c2b3a70 | René Nussbaumer | # chown takes -1 if you want to keep one part of the ownership, however
|
431 | 9c2b3a70 | René Nussbaumer | # None is Python standard for that. So we remap them here.
|
432 | 9c2b3a70 | René Nussbaumer | if uid is None: |
433 | 9c2b3a70 | René Nussbaumer | uid = -1
|
434 | 9c2b3a70 | René Nussbaumer | if gid is None: |
435 | 9c2b3a70 | René Nussbaumer | gid = -1
|
436 | 9c2b3a70 | René Nussbaumer | |
437 | b81b3c96 | René Nussbaumer | try:
|
438 | b81b3c96 | René Nussbaumer | st = _stat_fn(path) |
439 | b81b3c96 | René Nussbaumer | |
440 | b81b3c96 | René Nussbaumer | fmode = stat.S_IMODE(st[stat.ST_MODE]) |
441 | b81b3c96 | René Nussbaumer | if fmode != mode:
|
442 | b81b3c96 | René Nussbaumer | logging.debug("Changing mode of %s from %#o to %#o", path, fmode, mode)
|
443 | b81b3c96 | René Nussbaumer | _chmod_fn(path, mode) |
444 | b81b3c96 | René Nussbaumer | |
445 | b81b3c96 | René Nussbaumer | if max(uid, gid) > -1: |
446 | b81b3c96 | René Nussbaumer | fuid = st[stat.ST_UID] |
447 | b81b3c96 | René Nussbaumer | fgid = st[stat.ST_GID] |
448 | b81b3c96 | René Nussbaumer | if fuid != uid or fgid != gid: |
449 | b81b3c96 | René Nussbaumer | logging.debug("Changing owner of %s from UID %s/GID %s to"
|
450 | b81b3c96 | René Nussbaumer | " UID %s/GID %s", path, fuid, fgid, uid, gid)
|
451 | b81b3c96 | René Nussbaumer | _chown_fn(path, uid, gid) |
452 | b81b3c96 | René Nussbaumer | except EnvironmentError, err: |
453 | b81b3c96 | René Nussbaumer | if err.errno == errno.ENOENT:
|
454 | b81b3c96 | René Nussbaumer | if must_exist:
|
455 | b81b3c96 | René Nussbaumer | raise errors.GenericError("Path %s should exist, but does not" % path) |
456 | b81b3c96 | René Nussbaumer | else:
|
457 | b81b3c96 | René Nussbaumer | raise errors.GenericError("Error while changing permissions on %s: %s" % |
458 | b81b3c96 | René Nussbaumer | (path, err)) |
459 | b81b3c96 | René Nussbaumer | |
460 | b81b3c96 | René Nussbaumer | |
461 | b81b3c96 | René Nussbaumer | def MakeDirWithPerm(path, mode, uid, gid, _lstat_fn=os.lstat, |
462 | b81b3c96 | René Nussbaumer | _mkdir_fn=os.mkdir, _perm_fn=EnforcePermission): |
463 | b81b3c96 | René Nussbaumer | """Enforces that given path is a dir and has given mode, uid and gid set.
|
464 | b81b3c96 | René Nussbaumer |
|
465 | b81b3c96 | René Nussbaumer | @param path: The path to the file
|
466 | b81b3c96 | René Nussbaumer | @param mode: The mode of the file
|
467 | b81b3c96 | René Nussbaumer | @param uid: The uid of the owner of this file
|
468 | b81b3c96 | René Nussbaumer | @param gid: The gid of the owner of this file
|
469 | b81b3c96 | René Nussbaumer | @param _lstat_fn: Stat function to use (unittest only)
|
470 | b81b3c96 | René Nussbaumer | @param _mkdir_fn: mkdir function to use (unittest only)
|
471 | b81b3c96 | René Nussbaumer | @param _perm_fn: permission setter function to use (unittest only)
|
472 | b81b3c96 | René Nussbaumer |
|
473 | b81b3c96 | René Nussbaumer | """
|
474 | b81b3c96 | René Nussbaumer | logging.debug("Checking directory %s", path)
|
475 | b81b3c96 | René Nussbaumer | try:
|
476 | b81b3c96 | René Nussbaumer | # We don't want to follow symlinks
|
477 | b81b3c96 | René Nussbaumer | st = _lstat_fn(path) |
478 | b81b3c96 | René Nussbaumer | except EnvironmentError, err: |
479 | b81b3c96 | René Nussbaumer | if err.errno != errno.ENOENT:
|
480 | b81b3c96 | René Nussbaumer | raise errors.GenericError("stat(2) on %s failed: %s" % (path, err)) |
481 | b81b3c96 | René Nussbaumer | _mkdir_fn(path) |
482 | b81b3c96 | René Nussbaumer | else:
|
483 | b81b3c96 | René Nussbaumer | if not stat.S_ISDIR(st[stat.ST_MODE]): |
484 | b81b3c96 | René Nussbaumer | raise errors.GenericError(("Path %s is expected to be a directory, but " |
485 | b81b3c96 | René Nussbaumer | "isn't") % path)
|
486 | b81b3c96 | René Nussbaumer | |
487 | b81b3c96 | René Nussbaumer | _perm_fn(path, mode, uid=uid, gid=gid) |
488 | b81b3c96 | René Nussbaumer | |
489 | b81b3c96 | René Nussbaumer | |
490 | 3865ca48 | Michael Hanselmann | def Makedirs(path, mode=0750): |
491 | 3865ca48 | Michael Hanselmann | """Super-mkdir; create a leaf directory and all intermediate ones.
|
492 | 3865ca48 | Michael Hanselmann |
|
493 | 3865ca48 | Michael Hanselmann | This is a wrapper around C{os.makedirs} adding error handling not implemented
|
494 | 3865ca48 | Michael Hanselmann | before Python 2.5.
|
495 | 3865ca48 | Michael Hanselmann |
|
496 | 3865ca48 | Michael Hanselmann | """
|
497 | 3865ca48 | Michael Hanselmann | try:
|
498 | 3865ca48 | Michael Hanselmann | os.makedirs(path, mode) |
499 | 3865ca48 | Michael Hanselmann | except OSError, err: |
500 | 3865ca48 | Michael Hanselmann | # Ignore EEXIST. This is only handled in os.makedirs as included in
|
501 | 3865ca48 | Michael Hanselmann | # Python 2.5 and above.
|
502 | 3865ca48 | Michael Hanselmann | if err.errno != errno.EEXIST or not os.path.exists(path): |
503 | 3865ca48 | Michael Hanselmann | raise
|
504 | 3865ca48 | Michael Hanselmann | |
505 | 3865ca48 | Michael Hanselmann | |
506 | 3865ca48 | Michael Hanselmann | def TimestampForFilename(): |
507 | 3865ca48 | Michael Hanselmann | """Returns the current time formatted for filenames.
|
508 | 3865ca48 | Michael Hanselmann |
|
509 | 3865ca48 | Michael Hanselmann | The format doesn't contain colons as some shells and applications treat them
|
510 | 3865ca48 | Michael Hanselmann | as separators. Uses the local timezone.
|
511 | 3865ca48 | Michael Hanselmann |
|
512 | 3865ca48 | Michael Hanselmann | """
|
513 | 3865ca48 | Michael Hanselmann | return time.strftime("%Y-%m-%d_%H_%M_%S") |
514 | 3865ca48 | Michael Hanselmann | |
515 | 3865ca48 | Michael Hanselmann | |
516 | 3865ca48 | Michael Hanselmann | def CreateBackup(file_name): |
517 | 3865ca48 | Michael Hanselmann | """Creates a backup of a file.
|
518 | 3865ca48 | Michael Hanselmann |
|
519 | 3865ca48 | Michael Hanselmann | @type file_name: str
|
520 | 3865ca48 | Michael Hanselmann | @param file_name: file to be backed up
|
521 | 3865ca48 | Michael Hanselmann | @rtype: str
|
522 | 3865ca48 | Michael Hanselmann | @return: the path to the newly created backup
|
523 | 3865ca48 | Michael Hanselmann | @raise errors.ProgrammerError: for invalid file names
|
524 | 3865ca48 | Michael Hanselmann |
|
525 | 3865ca48 | Michael Hanselmann | """
|
526 | 3865ca48 | Michael Hanselmann | if not os.path.isfile(file_name): |
527 | 3865ca48 | Michael Hanselmann | raise errors.ProgrammerError("Can't make a backup of a non-file '%s'" % |
528 | 5ae4945a | Iustin Pop | file_name) |
529 | 3865ca48 | Michael Hanselmann | |
530 | 3865ca48 | Michael Hanselmann | prefix = ("%s.backup-%s." %
|
531 | 3865ca48 | Michael Hanselmann | (os.path.basename(file_name), TimestampForFilename())) |
532 | 3865ca48 | Michael Hanselmann | dir_name = os.path.dirname(file_name) |
533 | 3865ca48 | Michael Hanselmann | |
534 | d0c8c01d | Iustin Pop | fsrc = open(file_name, "rb") |
535 | 3865ca48 | Michael Hanselmann | try:
|
536 | 3865ca48 | Michael Hanselmann | (fd, backup_name) = tempfile.mkstemp(prefix=prefix, dir=dir_name) |
537 | d0c8c01d | Iustin Pop | fdst = os.fdopen(fd, "wb")
|
538 | 3865ca48 | Michael Hanselmann | try:
|
539 | 3865ca48 | Michael Hanselmann | logging.debug("Backing up %s at %s", file_name, backup_name)
|
540 | 3865ca48 | Michael Hanselmann | shutil.copyfileobj(fsrc, fdst) |
541 | 3865ca48 | Michael Hanselmann | finally:
|
542 | 3865ca48 | Michael Hanselmann | fdst.close() |
543 | 3865ca48 | Michael Hanselmann | finally:
|
544 | 3865ca48 | Michael Hanselmann | fsrc.close() |
545 | 3865ca48 | Michael Hanselmann | |
546 | 3865ca48 | Michael Hanselmann | return backup_name
|
547 | 3865ca48 | Michael Hanselmann | |
548 | 3865ca48 | Michael Hanselmann | |
549 | 2dbc6857 | Michael Hanselmann | def ListVisibleFiles(path, _is_mountpoint=os.path.ismount): |
550 | 3865ca48 | Michael Hanselmann | """Returns a list of visible files in a directory.
|
551 | 3865ca48 | Michael Hanselmann |
|
552 | 3865ca48 | Michael Hanselmann | @type path: str
|
553 | 3865ca48 | Michael Hanselmann | @param path: the directory to enumerate
|
554 | 3865ca48 | Michael Hanselmann | @rtype: list
|
555 | 3865ca48 | Michael Hanselmann | @return: the list of all files not starting with a dot
|
556 | 3865ca48 | Michael Hanselmann | @raise ProgrammerError: if L{path} is not an absolue and normalized path
|
557 | 3865ca48 | Michael Hanselmann |
|
558 | 3865ca48 | Michael Hanselmann | """
|
559 | 3865ca48 | Michael Hanselmann | if not IsNormAbsPath(path): |
560 | 3865ca48 | Michael Hanselmann | raise errors.ProgrammerError("Path passed to ListVisibleFiles is not" |
561 | 3865ca48 | Michael Hanselmann | " absolute/normalized: '%s'" % path)
|
562 | 2dbc6857 | Michael Hanselmann | |
563 | 2dbc6857 | Michael Hanselmann | mountpoint = _is_mountpoint(path) |
564 | 2dbc6857 | Michael Hanselmann | |
565 | 2dbc6857 | Michael Hanselmann | def fn(name): |
566 | 2dbc6857 | Michael Hanselmann | """File name filter.
|
567 | 2dbc6857 | Michael Hanselmann |
|
568 | 2dbc6857 | Michael Hanselmann | Ignores files starting with a dot (".") as by Unix convention they're
|
569 | 2dbc6857 | Michael Hanselmann | considered hidden. The "lost+found" directory found at the root of some
|
570 | 2dbc6857 | Michael Hanselmann | filesystems is also hidden.
|
571 | 2dbc6857 | Michael Hanselmann |
|
572 | 2dbc6857 | Michael Hanselmann | """
|
573 | 2dbc6857 | Michael Hanselmann | return not (name.startswith(".") or |
574 | 2dbc6857 | Michael Hanselmann | (mountpoint and name == _LOST_AND_FOUND and |
575 | 2dbc6857 | Michael Hanselmann | os.path.isdir(os.path.join(path, name)))) |
576 | 2dbc6857 | Michael Hanselmann | |
577 | 2dbc6857 | Michael Hanselmann | return filter(fn, os.listdir(path)) |
578 | 3865ca48 | Michael Hanselmann | |
579 | 3865ca48 | Michael Hanselmann | |
580 | 3865ca48 | Michael Hanselmann | def EnsureDirs(dirs): |
581 | 3865ca48 | Michael Hanselmann | """Make required directories, if they don't exist.
|
582 | 3865ca48 | Michael Hanselmann |
|
583 | 3865ca48 | Michael Hanselmann | @param dirs: list of tuples (dir_name, dir_mode)
|
584 | 3865ca48 | Michael Hanselmann | @type dirs: list of (string, integer)
|
585 | 3865ca48 | Michael Hanselmann |
|
586 | 3865ca48 | Michael Hanselmann | """
|
587 | 3865ca48 | Michael Hanselmann | for dir_name, dir_mode in dirs: |
588 | 3865ca48 | Michael Hanselmann | try:
|
589 | 3865ca48 | Michael Hanselmann | os.mkdir(dir_name, dir_mode) |
590 | 3865ca48 | Michael Hanselmann | except EnvironmentError, err: |
591 | 3865ca48 | Michael Hanselmann | if err.errno != errno.EEXIST:
|
592 | 3865ca48 | Michael Hanselmann | raise errors.GenericError("Cannot create needed directory" |
593 | 3865ca48 | Michael Hanselmann | " '%s': %s" % (dir_name, err))
|
594 | 3865ca48 | Michael Hanselmann | try:
|
595 | 3865ca48 | Michael Hanselmann | os.chmod(dir_name, dir_mode) |
596 | 3865ca48 | Michael Hanselmann | except EnvironmentError, err: |
597 | 3865ca48 | Michael Hanselmann | raise errors.GenericError("Cannot change directory permissions on" |
598 | 3865ca48 | Michael Hanselmann | " '%s': %s" % (dir_name, err))
|
599 | 3865ca48 | Michael Hanselmann | if not os.path.isdir(dir_name): |
600 | 3865ca48 | Michael Hanselmann | raise errors.GenericError("%s is not a directory" % dir_name) |
601 | 3865ca48 | Michael Hanselmann | |
602 | 3865ca48 | Michael Hanselmann | |
603 | 3865ca48 | Michael Hanselmann | def FindFile(name, search_path, test=os.path.exists): |
604 | 3865ca48 | Michael Hanselmann | """Look for a filesystem object in a given path.
|
605 | 3865ca48 | Michael Hanselmann |
|
606 | 3865ca48 | Michael Hanselmann | This is an abstract method to search for filesystem object (files,
|
607 | 3865ca48 | Michael Hanselmann | dirs) under a given search path.
|
608 | 3865ca48 | Michael Hanselmann |
|
609 | 3865ca48 | Michael Hanselmann | @type name: str
|
610 | 3865ca48 | Michael Hanselmann | @param name: the name to look for
|
611 | 3865ca48 | Michael Hanselmann | @type search_path: str
|
612 | 3865ca48 | Michael Hanselmann | @param search_path: location to start at
|
613 | 3865ca48 | Michael Hanselmann | @type test: callable
|
614 | 3865ca48 | Michael Hanselmann | @param test: a function taking one argument that should return True
|
615 | 3865ca48 | Michael Hanselmann | if the a given object is valid; the default value is
|
616 | 3865ca48 | Michael Hanselmann | os.path.exists, causing only existing files to be returned
|
617 | 3865ca48 | Michael Hanselmann | @rtype: str or None
|
618 | 3865ca48 | Michael Hanselmann | @return: full path to the object if found, None otherwise
|
619 | 3865ca48 | Michael Hanselmann |
|
620 | 3865ca48 | Michael Hanselmann | """
|
621 | 3865ca48 | Michael Hanselmann | # validate the filename mask
|
622 | 3865ca48 | Michael Hanselmann | if constants.EXT_PLUGIN_MASK.match(name) is None: |
623 | 3865ca48 | Michael Hanselmann | logging.critical("Invalid value passed for external script name: '%s'",
|
624 | 3865ca48 | Michael Hanselmann | name) |
625 | 3865ca48 | Michael Hanselmann | return None |
626 | 3865ca48 | Michael Hanselmann | |
627 | 3865ca48 | Michael Hanselmann | for dir_name in search_path: |
628 | 3865ca48 | Michael Hanselmann | # FIXME: investigate switch to PathJoin
|
629 | 3865ca48 | Michael Hanselmann | item_name = os.path.sep.join([dir_name, name]) |
630 | 3865ca48 | Michael Hanselmann | # check the user test and that we're indeed resolving to the given
|
631 | 3865ca48 | Michael Hanselmann | # basename
|
632 | 3865ca48 | Michael Hanselmann | if test(item_name) and os.path.basename(item_name) == name: |
633 | 3865ca48 | Michael Hanselmann | return item_name
|
634 | 3865ca48 | Michael Hanselmann | return None |
635 | 3865ca48 | Michael Hanselmann | |
636 | 3865ca48 | Michael Hanselmann | |
637 | 3865ca48 | Michael Hanselmann | def IsNormAbsPath(path): |
638 | 3865ca48 | Michael Hanselmann | """Check whether a path is absolute and also normalized
|
639 | 3865ca48 | Michael Hanselmann |
|
640 | 3865ca48 | Michael Hanselmann | This avoids things like /dir/../../other/path to be valid.
|
641 | 3865ca48 | Michael Hanselmann |
|
642 | 3865ca48 | Michael Hanselmann | """
|
643 | 3865ca48 | Michael Hanselmann | return os.path.normpath(path) == path and os.path.isabs(path) |
644 | 3865ca48 | Michael Hanselmann | |
645 | 3865ca48 | Michael Hanselmann | |
646 | fb17bebd | René Nussbaumer | def IsBelowDir(root, other_path): |
647 | fb17bebd | René Nussbaumer | """Check whether a path is below a root dir.
|
648 | fb17bebd | René Nussbaumer |
|
649 | fb17bebd | René Nussbaumer | This works around the nasty byte-byte comparisation of commonprefix.
|
650 | fb17bebd | René Nussbaumer |
|
651 | fb17bebd | René Nussbaumer | """
|
652 | fb17bebd | René Nussbaumer | if not (os.path.isabs(root) and os.path.isabs(other_path)): |
653 | fb17bebd | René Nussbaumer | raise ValueError("Provided paths '%s' and '%s' are not absolute" % |
654 | fb17bebd | René Nussbaumer | (root, other_path)) |
655 | fb17bebd | René Nussbaumer | prepared_root = "%s%s" % (os.path.normpath(root), os.sep)
|
656 | fb17bebd | René Nussbaumer | return os.path.commonprefix([prepared_root,
|
657 | fb17bebd | René Nussbaumer | os.path.normpath(other_path)]) == prepared_root |
658 | fb17bebd | René Nussbaumer | |
659 | fb17bebd | René Nussbaumer | |
660 | 3865ca48 | Michael Hanselmann | def PathJoin(*args): |
661 | 3865ca48 | Michael Hanselmann | """Safe-join a list of path components.
|
662 | 3865ca48 | Michael Hanselmann |
|
663 | 3865ca48 | Michael Hanselmann | Requirements:
|
664 | 3865ca48 | Michael Hanselmann | - the first argument must be an absolute path
|
665 | 3865ca48 | Michael Hanselmann | - no component in the path must have backtracking (e.g. /../),
|
666 | 3865ca48 | Michael Hanselmann | since we check for normalization at the end
|
667 | 3865ca48 | Michael Hanselmann |
|
668 | 3865ca48 | Michael Hanselmann | @param args: the path components to be joined
|
669 | 3865ca48 | Michael Hanselmann | @raise ValueError: for invalid paths
|
670 | 3865ca48 | Michael Hanselmann |
|
671 | 3865ca48 | Michael Hanselmann | """
|
672 | 3865ca48 | Michael Hanselmann | # ensure we're having at least one path passed in
|
673 | 3865ca48 | Michael Hanselmann | assert args
|
674 | 3865ca48 | Michael Hanselmann | # ensure the first component is an absolute and normalized path name
|
675 | 3865ca48 | Michael Hanselmann | root = args[0]
|
676 | 3865ca48 | Michael Hanselmann | if not IsNormAbsPath(root): |
677 | 3865ca48 | Michael Hanselmann | raise ValueError("Invalid parameter to PathJoin: '%s'" % str(args[0])) |
678 | 3865ca48 | Michael Hanselmann | result = os.path.join(*args) |
679 | 3865ca48 | Michael Hanselmann | # ensure that the whole path is normalized
|
680 | 3865ca48 | Michael Hanselmann | if not IsNormAbsPath(result): |
681 | 3865ca48 | Michael Hanselmann | raise ValueError("Invalid parameters to PathJoin: '%s'" % str(args)) |
682 | 3865ca48 | Michael Hanselmann | # check that we're still under the original prefix
|
683 | cf00dba0 | René Nussbaumer | if not IsBelowDir(root, result): |
684 | 3865ca48 | Michael Hanselmann | raise ValueError("Error: path joining resulted in different prefix" |
685 | cf00dba0 | René Nussbaumer | " (%s != %s)" % (result, root))
|
686 | 3865ca48 | Michael Hanselmann | return result
|
687 | 3865ca48 | Michael Hanselmann | |
688 | 3865ca48 | Michael Hanselmann | |
689 | 3865ca48 | Michael Hanselmann | def TailFile(fname, lines=20): |
690 | 3865ca48 | Michael Hanselmann | """Return the last lines from a file.
|
691 | 3865ca48 | Michael Hanselmann |
|
692 | 3865ca48 | Michael Hanselmann | @note: this function will only read and parse the last 4KB of
|
693 | 3865ca48 | Michael Hanselmann | the file; if the lines are very long, it could be that less
|
694 | 3865ca48 | Michael Hanselmann | than the requested number of lines are returned
|
695 | 3865ca48 | Michael Hanselmann |
|
696 | 3865ca48 | Michael Hanselmann | @param fname: the file name
|
697 | 3865ca48 | Michael Hanselmann | @type lines: int
|
698 | 3865ca48 | Michael Hanselmann | @param lines: the (maximum) number of lines to return
|
699 | 3865ca48 | Michael Hanselmann |
|
700 | 3865ca48 | Michael Hanselmann | """
|
701 | 3865ca48 | Michael Hanselmann | fd = open(fname, "r") |
702 | 3865ca48 | Michael Hanselmann | try:
|
703 | 3865ca48 | Michael Hanselmann | fd.seek(0, 2) |
704 | 3865ca48 | Michael Hanselmann | pos = fd.tell() |
705 | e687ec01 | Michael Hanselmann | pos = max(0, pos - 4096) |
706 | 3865ca48 | Michael Hanselmann | fd.seek(pos, 0)
|
707 | 3865ca48 | Michael Hanselmann | raw_data = fd.read() |
708 | 3865ca48 | Michael Hanselmann | finally:
|
709 | 3865ca48 | Michael Hanselmann | fd.close() |
710 | 3865ca48 | Michael Hanselmann | |
711 | 3865ca48 | Michael Hanselmann | rows = raw_data.splitlines() |
712 | 3865ca48 | Michael Hanselmann | return rows[-lines:]
|
713 | 3865ca48 | Michael Hanselmann | |
714 | 3865ca48 | Michael Hanselmann | |
715 | 3865ca48 | Michael Hanselmann | def BytesToMebibyte(value): |
716 | 3865ca48 | Michael Hanselmann | """Converts bytes to mebibytes.
|
717 | 3865ca48 | Michael Hanselmann |
|
718 | 3865ca48 | Michael Hanselmann | @type value: int
|
719 | 3865ca48 | Michael Hanselmann | @param value: Value in bytes
|
720 | 3865ca48 | Michael Hanselmann | @rtype: int
|
721 | 3865ca48 | Michael Hanselmann | @return: Value in mebibytes
|
722 | 3865ca48 | Michael Hanselmann |
|
723 | 3865ca48 | Michael Hanselmann | """
|
724 | 3865ca48 | Michael Hanselmann | return int(round(value / (1024.0 * 1024.0), 0)) |
725 | 3865ca48 | Michael Hanselmann | |
726 | 3865ca48 | Michael Hanselmann | |
727 | 3865ca48 | Michael Hanselmann | def CalculateDirectorySize(path): |
728 | 3865ca48 | Michael Hanselmann | """Calculates the size of a directory recursively.
|
729 | 3865ca48 | Michael Hanselmann |
|
730 | 3865ca48 | Michael Hanselmann | @type path: string
|
731 | 3865ca48 | Michael Hanselmann | @param path: Path to directory
|
732 | 3865ca48 | Michael Hanselmann | @rtype: int
|
733 | 3865ca48 | Michael Hanselmann | @return: Size in mebibytes
|
734 | 3865ca48 | Michael Hanselmann |
|
735 | 3865ca48 | Michael Hanselmann | """
|
736 | 3865ca48 | Michael Hanselmann | size = 0
|
737 | 3865ca48 | Michael Hanselmann | |
738 | 3865ca48 | Michael Hanselmann | for (curpath, _, files) in os.walk(path): |
739 | 3865ca48 | Michael Hanselmann | for filename in files: |
740 | 3865ca48 | Michael Hanselmann | st = os.lstat(PathJoin(curpath, filename)) |
741 | 3865ca48 | Michael Hanselmann | size += st.st_size |
742 | 3865ca48 | Michael Hanselmann | |
743 | 3865ca48 | Michael Hanselmann | return BytesToMebibyte(size)
|
744 | 3865ca48 | Michael Hanselmann | |
745 | 3865ca48 | Michael Hanselmann | |
746 | 3865ca48 | Michael Hanselmann | def GetFilesystemStats(path): |
747 | 3865ca48 | Michael Hanselmann | """Returns the total and free space on a filesystem.
|
748 | 3865ca48 | Michael Hanselmann |
|
749 | 3865ca48 | Michael Hanselmann | @type path: string
|
750 | 3865ca48 | Michael Hanselmann | @param path: Path on filesystem to be examined
|
751 | 3865ca48 | Michael Hanselmann | @rtype: int
|
752 | 3865ca48 | Michael Hanselmann | @return: tuple of (Total space, Free space) in mebibytes
|
753 | 3865ca48 | Michael Hanselmann |
|
754 | 3865ca48 | Michael Hanselmann | """
|
755 | 3865ca48 | Michael Hanselmann | st = os.statvfs(path) |
756 | 3865ca48 | Michael Hanselmann | |
757 | 3865ca48 | Michael Hanselmann | fsize = BytesToMebibyte(st.f_bavail * st.f_frsize) |
758 | 3865ca48 | Michael Hanselmann | tsize = BytesToMebibyte(st.f_blocks * st.f_frsize) |
759 | 3865ca48 | Michael Hanselmann | return (tsize, fsize)
|
760 | 3865ca48 | Michael Hanselmann | |
761 | 3865ca48 | Michael Hanselmann | |
762 | 3865ca48 | Michael Hanselmann | def ReadPidFile(pidfile): |
763 | 3865ca48 | Michael Hanselmann | """Read a pid from a file.
|
764 | 3865ca48 | Michael Hanselmann |
|
765 | 3865ca48 | Michael Hanselmann | @type pidfile: string
|
766 | 3865ca48 | Michael Hanselmann | @param pidfile: path to the file containing the pid
|
767 | 3865ca48 | Michael Hanselmann | @rtype: int
|
768 | 3865ca48 | Michael Hanselmann | @return: The process id, if the file exists and contains a valid PID,
|
769 | 3865ca48 | Michael Hanselmann | otherwise 0
|
770 | 3865ca48 | Michael Hanselmann |
|
771 | 3865ca48 | Michael Hanselmann | """
|
772 | 3865ca48 | Michael Hanselmann | try:
|
773 | 3865ca48 | Michael Hanselmann | raw_data = ReadOneLineFile(pidfile) |
774 | 3865ca48 | Michael Hanselmann | except EnvironmentError, err: |
775 | 3865ca48 | Michael Hanselmann | if err.errno != errno.ENOENT:
|
776 | 3865ca48 | Michael Hanselmann | logging.exception("Can't read pid file")
|
777 | 3865ca48 | Michael Hanselmann | return 0 |
778 | 3865ca48 | Michael Hanselmann | |
779 | b6522276 | Michael Hanselmann | return _ParsePidFileContents(raw_data)
|
780 | b6522276 | Michael Hanselmann | |
781 | b6522276 | Michael Hanselmann | |
782 | b6522276 | Michael Hanselmann | def _ParsePidFileContents(data): |
783 | b6522276 | Michael Hanselmann | """Tries to extract a process ID from a PID file's content.
|
784 | b6522276 | Michael Hanselmann |
|
785 | b6522276 | Michael Hanselmann | @type data: string
|
786 | b6522276 | Michael Hanselmann | @rtype: int
|
787 | b6522276 | Michael Hanselmann | @return: Zero if nothing could be read, PID otherwise
|
788 | b6522276 | Michael Hanselmann |
|
789 | b6522276 | Michael Hanselmann | """
|
790 | 3865ca48 | Michael Hanselmann | try:
|
791 | b6522276 | Michael Hanselmann | pid = int(data)
|
792 | b6522276 | Michael Hanselmann | except (TypeError, ValueError): |
793 | 3865ca48 | Michael Hanselmann | logging.info("Can't parse pid file contents", exc_info=True) |
794 | 3865ca48 | Michael Hanselmann | return 0 |
795 | b6522276 | Michael Hanselmann | else:
|
796 | b6522276 | Michael Hanselmann | return pid
|
797 | 3865ca48 | Michael Hanselmann | |
798 | 3865ca48 | Michael Hanselmann | |
799 | 3865ca48 | Michael Hanselmann | def ReadLockedPidFile(path): |
800 | 3865ca48 | Michael Hanselmann | """Reads a locked PID file.
|
801 | 3865ca48 | Michael Hanselmann |
|
802 | a4ccecf6 | Michael Hanselmann | This can be used together with L{utils.process.StartDaemon}.
|
803 | 3865ca48 | Michael Hanselmann |
|
804 | 3865ca48 | Michael Hanselmann | @type path: string
|
805 | 3865ca48 | Michael Hanselmann | @param path: Path to PID file
|
806 | 3865ca48 | Michael Hanselmann | @return: PID as integer or, if file was unlocked or couldn't be opened, None
|
807 | 3865ca48 | Michael Hanselmann |
|
808 | 3865ca48 | Michael Hanselmann | """
|
809 | 3865ca48 | Michael Hanselmann | try:
|
810 | 3865ca48 | Michael Hanselmann | fd = os.open(path, os.O_RDONLY) |
811 | 3865ca48 | Michael Hanselmann | except EnvironmentError, err: |
812 | 3865ca48 | Michael Hanselmann | if err.errno == errno.ENOENT:
|
813 | 3865ca48 | Michael Hanselmann | # PID file doesn't exist
|
814 | 3865ca48 | Michael Hanselmann | return None |
815 | 3865ca48 | Michael Hanselmann | raise
|
816 | 3865ca48 | Michael Hanselmann | |
817 | 3865ca48 | Michael Hanselmann | try:
|
818 | 3865ca48 | Michael Hanselmann | try:
|
819 | 3865ca48 | Michael Hanselmann | # Try to acquire lock
|
820 | 3865ca48 | Michael Hanselmann | filelock.LockFile(fd) |
821 | 3865ca48 | Michael Hanselmann | except errors.LockError:
|
822 | 3865ca48 | Michael Hanselmann | # Couldn't lock, daemon is running
|
823 | 3865ca48 | Michael Hanselmann | return int(os.read(fd, 100)) |
824 | 3865ca48 | Michael Hanselmann | finally:
|
825 | 3865ca48 | Michael Hanselmann | os.close(fd) |
826 | 3865ca48 | Michael Hanselmann | |
827 | 3865ca48 | Michael Hanselmann | return None |
828 | 3865ca48 | Michael Hanselmann | |
829 | 3865ca48 | Michael Hanselmann | |
830 | 3865ca48 | Michael Hanselmann | def AddAuthorizedKey(file_obj, key): |
831 | 3865ca48 | Michael Hanselmann | """Adds an SSH public key to an authorized_keys file.
|
832 | 3865ca48 | Michael Hanselmann |
|
833 | 3865ca48 | Michael Hanselmann | @type file_obj: str or file handle
|
834 | 3865ca48 | Michael Hanselmann | @param file_obj: path to authorized_keys file
|
835 | 3865ca48 | Michael Hanselmann | @type key: str
|
836 | 3865ca48 | Michael Hanselmann | @param key: string containing key
|
837 | 3865ca48 | Michael Hanselmann |
|
838 | 3865ca48 | Michael Hanselmann | """
|
839 | 3865ca48 | Michael Hanselmann | key_fields = key.split() |
840 | 3865ca48 | Michael Hanselmann | |
841 | 3865ca48 | Michael Hanselmann | if isinstance(file_obj, basestring): |
842 | d0c8c01d | Iustin Pop | f = open(file_obj, "a+") |
843 | 3865ca48 | Michael Hanselmann | else:
|
844 | 3865ca48 | Michael Hanselmann | f = file_obj |
845 | 3865ca48 | Michael Hanselmann | |
846 | 3865ca48 | Michael Hanselmann | try:
|
847 | 3865ca48 | Michael Hanselmann | nl = True
|
848 | 3865ca48 | Michael Hanselmann | for line in f: |
849 | 3865ca48 | Michael Hanselmann | # Ignore whitespace changes
|
850 | 3865ca48 | Michael Hanselmann | if line.split() == key_fields:
|
851 | 3865ca48 | Michael Hanselmann | break
|
852 | d0c8c01d | Iustin Pop | nl = line.endswith("\n")
|
853 | 3865ca48 | Michael Hanselmann | else:
|
854 | 3865ca48 | Michael Hanselmann | if not nl: |
855 | 3865ca48 | Michael Hanselmann | f.write("\n")
|
856 | d0c8c01d | Iustin Pop | f.write(key.rstrip("\r\n"))
|
857 | 3865ca48 | Michael Hanselmann | f.write("\n")
|
858 | 3865ca48 | Michael Hanselmann | f.flush() |
859 | 3865ca48 | Michael Hanselmann | finally:
|
860 | 3865ca48 | Michael Hanselmann | f.close() |
861 | 3865ca48 | Michael Hanselmann | |
862 | 3865ca48 | Michael Hanselmann | |
863 | 3865ca48 | Michael Hanselmann | def RemoveAuthorizedKey(file_name, key): |
864 | 3865ca48 | Michael Hanselmann | """Removes an SSH public key from an authorized_keys file.
|
865 | 3865ca48 | Michael Hanselmann |
|
866 | 3865ca48 | Michael Hanselmann | @type file_name: str
|
867 | 3865ca48 | Michael Hanselmann | @param file_name: path to authorized_keys file
|
868 | 3865ca48 | Michael Hanselmann | @type key: str
|
869 | 3865ca48 | Michael Hanselmann | @param key: string containing key
|
870 | 3865ca48 | Michael Hanselmann |
|
871 | 3865ca48 | Michael Hanselmann | """
|
872 | 3865ca48 | Michael Hanselmann | key_fields = key.split() |
873 | 3865ca48 | Michael Hanselmann | |
874 | 3865ca48 | Michael Hanselmann | fd, tmpname = tempfile.mkstemp(dir=os.path.dirname(file_name)) |
875 | 3865ca48 | Michael Hanselmann | try:
|
876 | d0c8c01d | Iustin Pop | out = os.fdopen(fd, "w")
|
877 | 3865ca48 | Michael Hanselmann | try:
|
878 | d0c8c01d | Iustin Pop | f = open(file_name, "r") |
879 | 3865ca48 | Michael Hanselmann | try:
|
880 | 3865ca48 | Michael Hanselmann | for line in f: |
881 | 3865ca48 | Michael Hanselmann | # Ignore whitespace changes while comparing lines
|
882 | 3865ca48 | Michael Hanselmann | if line.split() != key_fields:
|
883 | 3865ca48 | Michael Hanselmann | out.write(line) |
884 | 3865ca48 | Michael Hanselmann | |
885 | 3865ca48 | Michael Hanselmann | out.flush() |
886 | 3865ca48 | Michael Hanselmann | os.rename(tmpname, file_name) |
887 | 3865ca48 | Michael Hanselmann | finally:
|
888 | 3865ca48 | Michael Hanselmann | f.close() |
889 | 3865ca48 | Michael Hanselmann | finally:
|
890 | 3865ca48 | Michael Hanselmann | out.close() |
891 | 3865ca48 | Michael Hanselmann | except:
|
892 | 3865ca48 | Michael Hanselmann | RemoveFile(tmpname) |
893 | 3865ca48 | Michael Hanselmann | raise
|
894 | 3865ca48 | Michael Hanselmann | |
895 | 3865ca48 | Michael Hanselmann | |
896 | 3865ca48 | Michael Hanselmann | def DaemonPidFileName(name): |
897 | 3865ca48 | Michael Hanselmann | """Compute a ganeti pid file absolute path
|
898 | 3865ca48 | Michael Hanselmann |
|
899 | 3865ca48 | Michael Hanselmann | @type name: str
|
900 | 3865ca48 | Michael Hanselmann | @param name: the daemon name
|
901 | 3865ca48 | Michael Hanselmann | @rtype: str
|
902 | 3865ca48 | Michael Hanselmann | @return: the full path to the pidfile corresponding to the given
|
903 | 3865ca48 | Michael Hanselmann | daemon name
|
904 | 3865ca48 | Michael Hanselmann |
|
905 | 3865ca48 | Michael Hanselmann | """
|
906 | 3865ca48 | Michael Hanselmann | return PathJoin(constants.RUN_GANETI_DIR, "%s.pid" % name) |
907 | 3865ca48 | Michael Hanselmann | |
908 | 3865ca48 | Michael Hanselmann | |
909 | 3865ca48 | Michael Hanselmann | def WritePidFile(pidfile): |
910 | 3865ca48 | Michael Hanselmann | """Write the current process pidfile.
|
911 | 3865ca48 | Michael Hanselmann |
|
912 | 3865ca48 | Michael Hanselmann | @type pidfile: string
|
913 | 3865ca48 | Michael Hanselmann | @param pidfile: the path to the file to be written
|
914 | 3865ca48 | Michael Hanselmann | @raise errors.LockError: if the pid file already exists and
|
915 | 3865ca48 | Michael Hanselmann | points to a live process
|
916 | 3865ca48 | Michael Hanselmann | @rtype: int
|
917 | 3865ca48 | Michael Hanselmann | @return: the file descriptor of the lock file; do not close this unless
|
918 | 3865ca48 | Michael Hanselmann | you want to unlock the pid file
|
919 | 3865ca48 | Michael Hanselmann |
|
920 | 3865ca48 | Michael Hanselmann | """
|
921 | 3865ca48 | Michael Hanselmann | # We don't rename nor truncate the file to not drop locks under
|
922 | 3865ca48 | Michael Hanselmann | # existing processes
|
923 | b6522276 | Michael Hanselmann | fd_pidfile = os.open(pidfile, os.O_RDWR | os.O_CREAT, 0600)
|
924 | 3865ca48 | Michael Hanselmann | |
925 | 3865ca48 | Michael Hanselmann | # Lock the PID file (and fail if not possible to do so). Any code
|
926 | 3865ca48 | Michael Hanselmann | # wanting to send a signal to the daemon should try to lock the PID
|
927 | 3865ca48 | Michael Hanselmann | # file before reading it. If acquiring the lock succeeds, the daemon is
|
928 | 3865ca48 | Michael Hanselmann | # no longer running and the signal should not be sent.
|
929 | b6522276 | Michael Hanselmann | try:
|
930 | b6522276 | Michael Hanselmann | filelock.LockFile(fd_pidfile) |
931 | b6522276 | Michael Hanselmann | except errors.LockError:
|
932 | b6522276 | Michael Hanselmann | msg = ["PID file '%s' is already locked by another process" % pidfile]
|
933 | b6522276 | Michael Hanselmann | # Try to read PID file
|
934 | b6522276 | Michael Hanselmann | pid = _ParsePidFileContents(os.read(fd_pidfile, 100))
|
935 | b6522276 | Michael Hanselmann | if pid > 0: |
936 | b6522276 | Michael Hanselmann | msg.append(", PID read from file is %s" % pid)
|
937 | b6522276 | Michael Hanselmann | raise errors.PidFileLockError("".join(msg)) |
938 | 3865ca48 | Michael Hanselmann | |
939 | 3865ca48 | Michael Hanselmann | os.write(fd_pidfile, "%d\n" % os.getpid())
|
940 | 3865ca48 | Michael Hanselmann | |
941 | 3865ca48 | Michael Hanselmann | return fd_pidfile
|
942 | 3865ca48 | Michael Hanselmann | |
943 | 3865ca48 | Michael Hanselmann | |
944 | 3865ca48 | Michael Hanselmann | def ReadWatcherPauseFile(filename, now=None, remove_after=3600): |
945 | 3865ca48 | Michael Hanselmann | """Reads the watcher pause file.
|
946 | 3865ca48 | Michael Hanselmann |
|
947 | 3865ca48 | Michael Hanselmann | @type filename: string
|
948 | 3865ca48 | Michael Hanselmann | @param filename: Path to watcher pause file
|
949 | 3865ca48 | Michael Hanselmann | @type now: None, float or int
|
950 | 3865ca48 | Michael Hanselmann | @param now: Current time as Unix timestamp
|
951 | 3865ca48 | Michael Hanselmann | @type remove_after: int
|
952 | 3865ca48 | Michael Hanselmann | @param remove_after: Remove watcher pause file after specified amount of
|
953 | 3865ca48 | Michael Hanselmann | seconds past the pause end time
|
954 | 3865ca48 | Michael Hanselmann |
|
955 | 3865ca48 | Michael Hanselmann | """
|
956 | 3865ca48 | Michael Hanselmann | if now is None: |
957 | 3865ca48 | Michael Hanselmann | now = time.time() |
958 | 3865ca48 | Michael Hanselmann | |
959 | 3865ca48 | Michael Hanselmann | try:
|
960 | 3865ca48 | Michael Hanselmann | value = ReadFile(filename) |
961 | 3865ca48 | Michael Hanselmann | except IOError, err: |
962 | 3865ca48 | Michael Hanselmann | if err.errno != errno.ENOENT:
|
963 | 3865ca48 | Michael Hanselmann | raise
|
964 | 3865ca48 | Michael Hanselmann | value = None
|
965 | 3865ca48 | Michael Hanselmann | |
966 | 3865ca48 | Michael Hanselmann | if value is not None: |
967 | 3865ca48 | Michael Hanselmann | try:
|
968 | 3865ca48 | Michael Hanselmann | value = int(value)
|
969 | 3865ca48 | Michael Hanselmann | except ValueError: |
970 | 3865ca48 | Michael Hanselmann | logging.warning(("Watcher pause file (%s) contains invalid value,"
|
971 | 3865ca48 | Michael Hanselmann | " removing it"), filename)
|
972 | 3865ca48 | Michael Hanselmann | RemoveFile(filename) |
973 | 3865ca48 | Michael Hanselmann | value = None
|
974 | 3865ca48 | Michael Hanselmann | |
975 | 3865ca48 | Michael Hanselmann | if value is not None: |
976 | 3865ca48 | Michael Hanselmann | # Remove file if it's outdated
|
977 | 3865ca48 | Michael Hanselmann | if now > (value + remove_after):
|
978 | 3865ca48 | Michael Hanselmann | RemoveFile(filename) |
979 | 3865ca48 | Michael Hanselmann | value = None
|
980 | 3865ca48 | Michael Hanselmann | |
981 | 3865ca48 | Michael Hanselmann | elif now > value:
|
982 | 3865ca48 | Michael Hanselmann | value = None
|
983 | 3865ca48 | Michael Hanselmann | |
984 | 3865ca48 | Michael Hanselmann | return value
|
985 | 90e234a6 | Michael Hanselmann | |
986 | 90e234a6 | Michael Hanselmann | |
987 | 90e234a6 | Michael Hanselmann | def NewUUID(): |
988 | 90e234a6 | Michael Hanselmann | """Returns a random UUID.
|
989 | 90e234a6 | Michael Hanselmann |
|
990 | 90e234a6 | Michael Hanselmann | @note: This is a Linux-specific method as it uses the /proc
|
991 | 90e234a6 | Michael Hanselmann | filesystem.
|
992 | 90e234a6 | Michael Hanselmann | @rtype: str
|
993 | 90e234a6 | Michael Hanselmann |
|
994 | 90e234a6 | Michael Hanselmann | """
|
995 | 90e234a6 | Michael Hanselmann | return ReadFile(_RANDOM_UUID_FILE, size=128).rstrip("\n") |
996 | 0c1a5b1e | Agata Murawska | |
997 | 0c1a5b1e | Agata Murawska | |
998 | 0c1a5b1e | Agata Murawska | class TemporaryFileManager(object): |
999 | 0c1a5b1e | Agata Murawska | """Stores the list of files to be deleted and removes them on demand.
|
1000 | 0c1a5b1e | Agata Murawska |
|
1001 | 0c1a5b1e | Agata Murawska | """
|
1002 | 0c1a5b1e | Agata Murawska | |
1003 | 0c1a5b1e | Agata Murawska | def __init__(self): |
1004 | 0c1a5b1e | Agata Murawska | self._files = []
|
1005 | 0c1a5b1e | Agata Murawska | |
1006 | 0c1a5b1e | Agata Murawska | def __del__(self): |
1007 | 0c1a5b1e | Agata Murawska | self.Cleanup()
|
1008 | 0c1a5b1e | Agata Murawska | |
1009 | 0c1a5b1e | Agata Murawska | def Add(self, filename): |
1010 | 0c1a5b1e | Agata Murawska | """Add file to list of files to be deleted.
|
1011 | 0c1a5b1e | Agata Murawska |
|
1012 | 0c1a5b1e | Agata Murawska | @type filename: string
|
1013 | 0c1a5b1e | Agata Murawska | @param filename: path to filename to be added
|
1014 | 0c1a5b1e | Agata Murawska |
|
1015 | 0c1a5b1e | Agata Murawska | """
|
1016 | 0c1a5b1e | Agata Murawska | self._files.append(filename)
|
1017 | 0c1a5b1e | Agata Murawska | |
1018 | 0c1a5b1e | Agata Murawska | def Remove(self, filename): |
1019 | 0c1a5b1e | Agata Murawska | """Remove file from list of files to be deleted.
|
1020 | 0c1a5b1e | Agata Murawska |
|
1021 | 0c1a5b1e | Agata Murawska | @type filename: string
|
1022 | 0c1a5b1e | Agata Murawska | @param filename: path to filename to be deleted
|
1023 | 0c1a5b1e | Agata Murawska |
|
1024 | 0c1a5b1e | Agata Murawska | """
|
1025 | 0c1a5b1e | Agata Murawska | self._files.remove(filename)
|
1026 | 0c1a5b1e | Agata Murawska | |
1027 | 0c1a5b1e | Agata Murawska | def Cleanup(self): |
1028 | 0c1a5b1e | Agata Murawska | """Delete all files marked for deletion
|
1029 | 0c1a5b1e | Agata Murawska |
|
1030 | 0c1a5b1e | Agata Murawska | """
|
1031 | 0c1a5b1e | Agata Murawska | while self._files: |
1032 | 0c1a5b1e | Agata Murawska | RemoveFile(self._files.pop()) |