root / lib / utils / __init__.py @ adc523ab
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1 | 2f31098c | Iustin Pop | #
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2 | a8083063 | Iustin Pop | #
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3 | a8083063 | Iustin Pop | |
4 | 4fd029cf | Michael Hanselmann | # Copyright (C) 2006, 2007, 2010, 2011 Google Inc.
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5 | a8083063 | Iustin Pop | #
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6 | a8083063 | Iustin Pop | # This program is free software; you can redistribute it and/or modify
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7 | a8083063 | Iustin Pop | # it under the terms of the GNU General Public License as published by
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8 | a8083063 | Iustin Pop | # the Free Software Foundation; either version 2 of the License, or
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9 | a8083063 | Iustin Pop | # (at your option) any later version.
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10 | a8083063 | Iustin Pop | #
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11 | a8083063 | Iustin Pop | # This program is distributed in the hope that it will be useful, but
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12 | a8083063 | Iustin Pop | # WITHOUT ANY WARRANTY; without even the implied warranty of
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13 | a8083063 | Iustin Pop | # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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14 | a8083063 | Iustin Pop | # General Public License for more details.
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15 | a8083063 | Iustin Pop | #
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16 | a8083063 | Iustin Pop | # You should have received a copy of the GNU General Public License
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17 | a8083063 | Iustin Pop | # along with this program; if not, write to the Free Software
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18 | a8083063 | Iustin Pop | # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
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19 | a8083063 | Iustin Pop | # 02110-1301, USA.
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20 | a8083063 | Iustin Pop | |
21 | a8083063 | Iustin Pop | |
22 | 58885d79 | Iustin Pop | """Ganeti utility module.
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23 | 58885d79 | Iustin Pop |
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24 | 58885d79 | Iustin Pop | This module holds functions that can be used in both daemons (all) and
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25 | 58885d79 | Iustin Pop | the command line scripts.
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26 | 899d2a81 | Michael Hanselmann |
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27 | a8083063 | Iustin Pop | """
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28 | a8083063 | Iustin Pop | |
29 | 63fc4229 | Michael Hanselmann | # Allow wildcard import in pylint: disable-msg=W0401
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30 | a8083063 | Iustin Pop | |
31 | a8083063 | Iustin Pop | import os |
32 | a8083063 | Iustin Pop | import re |
33 | 4ca1b175 | Alexander Schreiber | import errno |
34 | 2f8b60b3 | Iustin Pop | import pwd |
35 | 78feb6fb | Guido Trotter | import itertools |
36 | 9c233417 | Iustin Pop | import select |
37 | bb698c1f | Iustin Pop | import logging |
38 | de499029 | Michael Hanselmann | import signal |
39 | a8083063 | Iustin Pop | |
40 | a8083063 | Iustin Pop | from ganeti import errors |
41 | 3aecd2c7 | Iustin Pop | from ganeti import constants |
42 | 716a32cb | Guido Trotter | from ganeti import compat |
43 | a8083063 | Iustin Pop | |
44 | 63fc4229 | Michael Hanselmann | from ganeti.utils.algo import * |
45 | 63fc4229 | Michael Hanselmann | from ganeti.utils.filelock import * |
46 | 63fc4229 | Michael Hanselmann | from ganeti.utils.hash import * |
47 | 63fc4229 | Michael Hanselmann | from ganeti.utils.io import * |
48 | 63fc4229 | Michael Hanselmann | from ganeti.utils.log import * |
49 | 63fc4229 | Michael Hanselmann | from ganeti.utils.mlock import * |
50 | 63fc4229 | Michael Hanselmann | from ganeti.utils.nodesetup import * |
51 | 63fc4229 | Michael Hanselmann | from ganeti.utils.process import * |
52 | 63fc4229 | Michael Hanselmann | from ganeti.utils.retry import * |
53 | 63fc4229 | Michael Hanselmann | from ganeti.utils.text import * |
54 | 63fc4229 | Michael Hanselmann | from ganeti.utils.wrapper import * |
55 | 63fc4229 | Michael Hanselmann | from ganeti.utils.x509 import * |
56 | 16abfbc2 | Alexander Schreiber | |
57 | 58885d79 | Iustin Pop | |
58 | 28f34048 | Michael Hanselmann | _VALID_SERVICE_NAME_RE = re.compile("^[-_.a-zA-Z0-9]{1,128}$")
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59 | 28f34048 | Michael Hanselmann | |
60 | 05636402 | Guido Trotter | UUID_RE = re.compile('^[a-f0-9]{8}-[a-f0-9]{4}-[a-f0-9]{4}-'
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61 | 05636402 | Guido Trotter | '[a-f0-9]{4}-[a-f0-9]{12}$')
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62 | 05636402 | Guido Trotter | |
63 | 7c0d6283 | Michael Hanselmann | |
64 | a5728081 | Guido Trotter | def ForceDictType(target, key_types, allowed_values=None): |
65 | a5728081 | Guido Trotter | """Force the values of a dict to have certain types.
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66 | a5728081 | Guido Trotter |
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67 | a5728081 | Guido Trotter | @type target: dict
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68 | a5728081 | Guido Trotter | @param target: the dict to update
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69 | a5728081 | Guido Trotter | @type key_types: dict
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70 | a5728081 | Guido Trotter | @param key_types: dict mapping target dict keys to types
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71 | a5728081 | Guido Trotter | in constants.ENFORCEABLE_TYPES
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72 | a5728081 | Guido Trotter | @type allowed_values: list
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73 | a5728081 | Guido Trotter | @keyword allowed_values: list of specially allowed values
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74 | a5728081 | Guido Trotter |
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75 | a5728081 | Guido Trotter | """
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76 | a5728081 | Guido Trotter | if allowed_values is None: |
77 | a5728081 | Guido Trotter | allowed_values = [] |
78 | a5728081 | Guido Trotter | |
79 | 8b46606c | Guido Trotter | if not isinstance(target, dict): |
80 | 8b46606c | Guido Trotter | msg = "Expected dictionary, got '%s'" % target
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81 | 8b46606c | Guido Trotter | raise errors.TypeEnforcementError(msg)
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82 | 8b46606c | Guido Trotter | |
83 | a5728081 | Guido Trotter | for key in target: |
84 | a5728081 | Guido Trotter | if key not in key_types: |
85 | 58a59652 | Iustin Pop | msg = "Unknown parameter '%s'" % key
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86 | a5728081 | Guido Trotter | raise errors.TypeEnforcementError(msg)
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87 | a5728081 | Guido Trotter | |
88 | a5728081 | Guido Trotter | if target[key] in allowed_values: |
89 | a5728081 | Guido Trotter | continue
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90 | a5728081 | Guido Trotter | |
91 | 29921401 | Iustin Pop | ktype = key_types[key] |
92 | 29921401 | Iustin Pop | if ktype not in constants.ENFORCEABLE_TYPES: |
93 | 29921401 | Iustin Pop | msg = "'%s' has non-enforceable type %s" % (key, ktype)
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94 | a5728081 | Guido Trotter | raise errors.ProgrammerError(msg)
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95 | a5728081 | Guido Trotter | |
96 | 59525e1f | Michael Hanselmann | if ktype in (constants.VTYPE_STRING, constants.VTYPE_MAYBE_STRING): |
97 | 59525e1f | Michael Hanselmann | if target[key] is None and ktype == constants.VTYPE_MAYBE_STRING: |
98 | 59525e1f | Michael Hanselmann | pass
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99 | 59525e1f | Michael Hanselmann | elif not isinstance(target[key], basestring): |
100 | a5728081 | Guido Trotter | if isinstance(target[key], bool) and not target[key]: |
101 | a5728081 | Guido Trotter | target[key] = ''
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102 | a5728081 | Guido Trotter | else:
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103 | a5728081 | Guido Trotter | msg = "'%s' (value %s) is not a valid string" % (key, target[key])
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104 | a5728081 | Guido Trotter | raise errors.TypeEnforcementError(msg)
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105 | 29921401 | Iustin Pop | elif ktype == constants.VTYPE_BOOL:
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106 | a5728081 | Guido Trotter | if isinstance(target[key], basestring) and target[key]: |
107 | a5728081 | Guido Trotter | if target[key].lower() == constants.VALUE_FALSE:
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108 | a5728081 | Guido Trotter | target[key] = False
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109 | a5728081 | Guido Trotter | elif target[key].lower() == constants.VALUE_TRUE:
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110 | a5728081 | Guido Trotter | target[key] = True
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111 | a5728081 | Guido Trotter | else:
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112 | a5728081 | Guido Trotter | msg = "'%s' (value %s) is not a valid boolean" % (key, target[key])
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113 | a5728081 | Guido Trotter | raise errors.TypeEnforcementError(msg)
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114 | a5728081 | Guido Trotter | elif target[key]:
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115 | a5728081 | Guido Trotter | target[key] = True
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116 | a5728081 | Guido Trotter | else:
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117 | a5728081 | Guido Trotter | target[key] = False
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118 | 29921401 | Iustin Pop | elif ktype == constants.VTYPE_SIZE:
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119 | a5728081 | Guido Trotter | try:
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120 | a5728081 | Guido Trotter | target[key] = ParseUnit(target[key]) |
121 | a5728081 | Guido Trotter | except errors.UnitParseError, err:
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122 | a5728081 | Guido Trotter | msg = "'%s' (value %s) is not a valid size. error: %s" % \
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123 | a5728081 | Guido Trotter | (key, target[key], err) |
124 | a5728081 | Guido Trotter | raise errors.TypeEnforcementError(msg)
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125 | 29921401 | Iustin Pop | elif ktype == constants.VTYPE_INT:
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126 | a5728081 | Guido Trotter | try:
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127 | a5728081 | Guido Trotter | target[key] = int(target[key])
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128 | a5728081 | Guido Trotter | except (ValueError, TypeError): |
129 | a5728081 | Guido Trotter | msg = "'%s' (value %s) is not a valid integer" % (key, target[key])
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130 | a5728081 | Guido Trotter | raise errors.TypeEnforcementError(msg)
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131 | a5728081 | Guido Trotter | |
132 | a5728081 | Guido Trotter | |
133 | 28f34048 | Michael Hanselmann | def ValidateServiceName(name): |
134 | 28f34048 | Michael Hanselmann | """Validate the given service name.
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135 | 28f34048 | Michael Hanselmann |
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136 | 28f34048 | Michael Hanselmann | @type name: number or string
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137 | 28f34048 | Michael Hanselmann | @param name: Service name or port specification
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138 | 28f34048 | Michael Hanselmann |
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139 | 28f34048 | Michael Hanselmann | """
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140 | 28f34048 | Michael Hanselmann | try:
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141 | 28f34048 | Michael Hanselmann | numport = int(name)
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142 | 28f34048 | Michael Hanselmann | except (ValueError, TypeError): |
143 | 28f34048 | Michael Hanselmann | # Non-numeric service name
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144 | 28f34048 | Michael Hanselmann | valid = _VALID_SERVICE_NAME_RE.match(name) |
145 | 28f34048 | Michael Hanselmann | else:
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146 | 28f34048 | Michael Hanselmann | # Numeric port (protocols other than TCP or UDP might need adjustments
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147 | 28f34048 | Michael Hanselmann | # here)
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148 | 28f34048 | Michael Hanselmann | valid = (numport >= 0 and numport < (1 << 16)) |
149 | 28f34048 | Michael Hanselmann | |
150 | 28f34048 | Michael Hanselmann | if not valid: |
151 | 28f34048 | Michael Hanselmann | raise errors.OpPrereqError("Invalid service name '%s'" % name, |
152 | 28f34048 | Michael Hanselmann | errors.ECODE_INVAL) |
153 | 28f34048 | Michael Hanselmann | |
154 | 28f34048 | Michael Hanselmann | return name
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155 | 28f34048 | Michael Hanselmann | |
156 | 28f34048 | Michael Hanselmann | |
157 | a8083063 | Iustin Pop | def ListVolumeGroups(): |
158 | a8083063 | Iustin Pop | """List volume groups and their size
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159 | a8083063 | Iustin Pop |
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160 | 58885d79 | Iustin Pop | @rtype: dict
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161 | 58885d79 | Iustin Pop | @return:
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162 | 58885d79 | Iustin Pop | Dictionary with keys volume name and values
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163 | 58885d79 | Iustin Pop | the size of the volume
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164 | a8083063 | Iustin Pop |
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165 | a8083063 | Iustin Pop | """
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166 | a8083063 | Iustin Pop | command = "vgs --noheadings --units m --nosuffix -o name,size"
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167 | a8083063 | Iustin Pop | result = RunCmd(command) |
168 | a8083063 | Iustin Pop | retval = {} |
169 | a8083063 | Iustin Pop | if result.failed:
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170 | a8083063 | Iustin Pop | return retval
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171 | a8083063 | Iustin Pop | |
172 | a8083063 | Iustin Pop | for line in result.stdout.splitlines(): |
173 | a8083063 | Iustin Pop | try:
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174 | a8083063 | Iustin Pop | name, size = line.split() |
175 | a8083063 | Iustin Pop | size = int(float(size)) |
176 | a8083063 | Iustin Pop | except (IndexError, ValueError), err: |
177 | bb698c1f | Iustin Pop | logging.error("Invalid output from vgs (%s): %s", err, line)
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178 | a8083063 | Iustin Pop | continue
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179 | a8083063 | Iustin Pop | |
180 | a8083063 | Iustin Pop | retval[name] = size |
181 | a8083063 | Iustin Pop | |
182 | a8083063 | Iustin Pop | return retval
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183 | a8083063 | Iustin Pop | |
184 | a8083063 | Iustin Pop | |
185 | a8083063 | Iustin Pop | def BridgeExists(bridge): |
186 | a8083063 | Iustin Pop | """Check whether the given bridge exists in the system
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187 | a8083063 | Iustin Pop |
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188 | 58885d79 | Iustin Pop | @type bridge: str
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189 | 58885d79 | Iustin Pop | @param bridge: the bridge name to check
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190 | 58885d79 | Iustin Pop | @rtype: boolean
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191 | 58885d79 | Iustin Pop | @return: True if it does
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192 | a8083063 | Iustin Pop |
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193 | a8083063 | Iustin Pop | """
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194 | a8083063 | Iustin Pop | return os.path.isdir("/sys/class/net/%s/bridge" % bridge) |
195 | a8083063 | Iustin Pop | |
196 | a8083063 | Iustin Pop | |
197 | a8083063 | Iustin Pop | def TryConvert(fn, val): |
198 | a8083063 | Iustin Pop | """Try to convert a value ignoring errors.
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199 | a8083063 | Iustin Pop |
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200 | 58885d79 | Iustin Pop | This function tries to apply function I{fn} to I{val}. If no
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201 | 58885d79 | Iustin Pop | C{ValueError} or C{TypeError} exceptions are raised, it will return
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202 | 58885d79 | Iustin Pop | the result, else it will return the original value. Any other
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203 | 58885d79 | Iustin Pop | exceptions are propagated to the caller.
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204 | 58885d79 | Iustin Pop |
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205 | 58885d79 | Iustin Pop | @type fn: callable
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206 | 58885d79 | Iustin Pop | @param fn: function to apply to the value
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207 | 58885d79 | Iustin Pop | @param val: the value to be converted
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208 | 58885d79 | Iustin Pop | @return: The converted value if the conversion was successful,
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209 | 58885d79 | Iustin Pop | otherwise the original value.
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210 | a8083063 | Iustin Pop |
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211 | a8083063 | Iustin Pop | """
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212 | a8083063 | Iustin Pop | try:
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213 | a8083063 | Iustin Pop | nv = fn(val) |
214 | 7c4d6c7b | Michael Hanselmann | except (ValueError, TypeError): |
215 | a8083063 | Iustin Pop | nv = val |
216 | a8083063 | Iustin Pop | return nv
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217 | a8083063 | Iustin Pop | |
218 | a8083063 | Iustin Pop | |
219 | 31155d60 | Balazs Lecz | def ParseCpuMask(cpu_mask): |
220 | 31155d60 | Balazs Lecz | """Parse a CPU mask definition and return the list of CPU IDs.
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221 | 31155d60 | Balazs Lecz |
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222 | 31155d60 | Balazs Lecz | CPU mask format: comma-separated list of CPU IDs
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223 | 31155d60 | Balazs Lecz | or dash-separated ID ranges
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224 | 31155d60 | Balazs Lecz | Example: "0-2,5" -> "0,1,2,5"
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225 | 31155d60 | Balazs Lecz |
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226 | 31155d60 | Balazs Lecz | @type cpu_mask: str
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227 | 31155d60 | Balazs Lecz | @param cpu_mask: CPU mask definition
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228 | 31155d60 | Balazs Lecz | @rtype: list of int
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229 | 31155d60 | Balazs Lecz | @return: list of CPU IDs
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230 | 31155d60 | Balazs Lecz |
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231 | 31155d60 | Balazs Lecz | """
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232 | 31155d60 | Balazs Lecz | if not cpu_mask: |
233 | 31155d60 | Balazs Lecz | return []
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234 | 31155d60 | Balazs Lecz | cpu_list = [] |
235 | 31155d60 | Balazs Lecz | for range_def in cpu_mask.split(","): |
236 | 31155d60 | Balazs Lecz | boundaries = range_def.split("-")
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237 | 31155d60 | Balazs Lecz | n_elements = len(boundaries)
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238 | 31155d60 | Balazs Lecz | if n_elements > 2: |
239 | 31155d60 | Balazs Lecz | raise errors.ParseError("Invalid CPU ID range definition" |
240 | 31155d60 | Balazs Lecz | " (only one hyphen allowed): %s" % range_def)
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241 | 31155d60 | Balazs Lecz | try:
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242 | 31155d60 | Balazs Lecz | lower = int(boundaries[0]) |
243 | 31155d60 | Balazs Lecz | except (ValueError, TypeError), err: |
244 | 31155d60 | Balazs Lecz | raise errors.ParseError("Invalid CPU ID value for lower boundary of" |
245 | 31155d60 | Balazs Lecz | " CPU ID range: %s" % str(err)) |
246 | 31155d60 | Balazs Lecz | try:
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247 | 31155d60 | Balazs Lecz | higher = int(boundaries[-1]) |
248 | 31155d60 | Balazs Lecz | except (ValueError, TypeError), err: |
249 | 31155d60 | Balazs Lecz | raise errors.ParseError("Invalid CPU ID value for higher boundary of" |
250 | 31155d60 | Balazs Lecz | " CPU ID range: %s" % str(err)) |
251 | 31155d60 | Balazs Lecz | if lower > higher:
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252 | 31155d60 | Balazs Lecz | raise errors.ParseError("Invalid CPU ID range definition" |
253 | 31155d60 | Balazs Lecz | " (%d > %d): %s" % (lower, higher, range_def))
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254 | 31155d60 | Balazs Lecz | cpu_list.extend(range(lower, higher + 1)) |
255 | 31155d60 | Balazs Lecz | return cpu_list
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256 | 31155d60 | Balazs Lecz | |
257 | 31155d60 | Balazs Lecz | |
258 | 257f4c0a | Iustin Pop | def GetHomeDir(user, default=None): |
259 | 257f4c0a | Iustin Pop | """Try to get the homedir of the given user.
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260 | 257f4c0a | Iustin Pop |
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261 | 257f4c0a | Iustin Pop | The user can be passed either as a string (denoting the name) or as
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262 | 257f4c0a | Iustin Pop | an integer (denoting the user id). If the user is not found, the
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263 | 257f4c0a | Iustin Pop | 'default' argument is returned, which defaults to None.
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264 | 2f8b60b3 | Iustin Pop |
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265 | 2f8b60b3 | Iustin Pop | """
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266 | 2f8b60b3 | Iustin Pop | try:
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267 | 257f4c0a | Iustin Pop | if isinstance(user, basestring): |
268 | 257f4c0a | Iustin Pop | result = pwd.getpwnam(user) |
269 | 257f4c0a | Iustin Pop | elif isinstance(user, (int, long)): |
270 | 257f4c0a | Iustin Pop | result = pwd.getpwuid(user) |
271 | 257f4c0a | Iustin Pop | else:
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272 | 257f4c0a | Iustin Pop | raise errors.ProgrammerError("Invalid type passed to GetHomeDir (%s)" % |
273 | 257f4c0a | Iustin Pop | type(user))
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274 | 2f8b60b3 | Iustin Pop | except KeyError: |
275 | 2f8b60b3 | Iustin Pop | return default
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276 | 2f8b60b3 | Iustin Pop | return result.pw_dir
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277 | 59072e7e | Michael Hanselmann | |
278 | 59072e7e | Michael Hanselmann | |
279 | 7b4126b7 | Iustin Pop | def FirstFree(seq, base=0): |
280 | 7b4126b7 | Iustin Pop | """Returns the first non-existing integer from seq.
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281 | 7b4126b7 | Iustin Pop |
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282 | 7b4126b7 | Iustin Pop | The seq argument should be a sorted list of positive integers. The
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283 | 7b4126b7 | Iustin Pop | first time the index of an element is smaller than the element
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284 | 7b4126b7 | Iustin Pop | value, the index will be returned.
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285 | 7b4126b7 | Iustin Pop |
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286 | 7b4126b7 | Iustin Pop | The base argument is used to start at a different offset,
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287 | 58885d79 | Iustin Pop | i.e. C{[3, 4, 6]} with I{offset=3} will return 5.
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288 | 58885d79 | Iustin Pop |
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289 | 58885d79 | Iustin Pop | Example: C{[0, 1, 3]} will return I{2}.
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290 | 7b4126b7 | Iustin Pop |
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291 | 58885d79 | Iustin Pop | @type seq: sequence
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292 | 58885d79 | Iustin Pop | @param seq: the sequence to be analyzed.
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293 | 58885d79 | Iustin Pop | @type base: int
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294 | 58885d79 | Iustin Pop | @param base: use this value as the base index of the sequence
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295 | 58885d79 | Iustin Pop | @rtype: int
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296 | 58885d79 | Iustin Pop | @return: the first non-used index in the sequence
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297 | 7b4126b7 | Iustin Pop |
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298 | 7b4126b7 | Iustin Pop | """
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299 | 7b4126b7 | Iustin Pop | for idx, elem in enumerate(seq): |
300 | 7b4126b7 | Iustin Pop | assert elem >= base, "Passed element is higher than base offset" |
301 | 7b4126b7 | Iustin Pop | if elem > idx + base:
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302 | 7b4126b7 | Iustin Pop | # idx is not used
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303 | 7b4126b7 | Iustin Pop | return idx + base
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304 | 7b4126b7 | Iustin Pop | return None |
305 | 7b4126b7 | Iustin Pop | |
306 | 7b4126b7 | Iustin Pop | |
307 | dfdc4060 | Guido Trotter | def SingleWaitForFdCondition(fdobj, event, timeout): |
308 | dcd511c8 | Guido Trotter | """Waits for a condition to occur on the socket.
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309 | dcd511c8 | Guido Trotter |
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310 | dfdc4060 | Guido Trotter | Immediately returns at the first interruption.
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311 | dfdc4060 | Guido Trotter |
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312 | dfdc4060 | Guido Trotter | @type fdobj: integer or object supporting a fileno() method
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313 | dfdc4060 | Guido Trotter | @param fdobj: entity to wait for events on
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314 | dfdc4060 | Guido Trotter | @type event: integer
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315 | dcd511c8 | Guido Trotter | @param event: ORed condition (see select module)
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316 | dcd511c8 | Guido Trotter | @type timeout: float or None
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317 | dcd511c8 | Guido Trotter | @param timeout: Timeout in seconds
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318 | dcd511c8 | Guido Trotter | @rtype: int or None
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319 | dcd511c8 | Guido Trotter | @return: None for timeout, otherwise occured conditions
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320 | dcd511c8 | Guido Trotter |
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321 | dcd511c8 | Guido Trotter | """
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322 | dcd511c8 | Guido Trotter | check = (event | select.POLLPRI | |
323 | dcd511c8 | Guido Trotter | select.POLLNVAL | select.POLLHUP | select.POLLERR) |
324 | dcd511c8 | Guido Trotter | |
325 | dcd511c8 | Guido Trotter | if timeout is not None: |
326 | dcd511c8 | Guido Trotter | # Poller object expects milliseconds
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327 | dcd511c8 | Guido Trotter | timeout *= 1000
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328 | dcd511c8 | Guido Trotter | |
329 | dcd511c8 | Guido Trotter | poller = select.poll() |
330 | dfdc4060 | Guido Trotter | poller.register(fdobj, event) |
331 | dcd511c8 | Guido Trotter | try:
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332 | dfdc4060 | Guido Trotter | # TODO: If the main thread receives a signal and we have no timeout, we
|
333 | dfdc4060 | Guido Trotter | # could wait forever. This should check a global "quit" flag or something
|
334 | dfdc4060 | Guido Trotter | # every so often.
|
335 | dfdc4060 | Guido Trotter | io_events = poller.poll(timeout) |
336 | dfdc4060 | Guido Trotter | except select.error, err:
|
337 | dfdc4060 | Guido Trotter | if err[0] != errno.EINTR: |
338 | dfdc4060 | Guido Trotter | raise
|
339 | dfdc4060 | Guido Trotter | io_events = [] |
340 | dfdc4060 | Guido Trotter | if io_events and io_events[0][1] & check: |
341 | dfdc4060 | Guido Trotter | return io_events[0][1] |
342 | dfdc4060 | Guido Trotter | else:
|
343 | dfdc4060 | Guido Trotter | return None |
344 | dfdc4060 | Guido Trotter | |
345 | dfdc4060 | Guido Trotter | |
346 | dfdc4060 | Guido Trotter | class FdConditionWaiterHelper(object): |
347 | dfdc4060 | Guido Trotter | """Retry helper for WaitForFdCondition.
|
348 | dfdc4060 | Guido Trotter |
|
349 | dfdc4060 | Guido Trotter | This class contains the retried and wait functions that make sure
|
350 | dfdc4060 | Guido Trotter | WaitForFdCondition can continue waiting until the timeout is actually
|
351 | dfdc4060 | Guido Trotter | expired.
|
352 | dfdc4060 | Guido Trotter |
|
353 | dfdc4060 | Guido Trotter | """
|
354 | dfdc4060 | Guido Trotter | |
355 | dfdc4060 | Guido Trotter | def __init__(self, timeout): |
356 | dfdc4060 | Guido Trotter | self.timeout = timeout
|
357 | dfdc4060 | Guido Trotter | |
358 | dfdc4060 | Guido Trotter | def Poll(self, fdobj, event): |
359 | dfdc4060 | Guido Trotter | result = SingleWaitForFdCondition(fdobj, event, self.timeout)
|
360 | dfdc4060 | Guido Trotter | if result is None: |
361 | dfdc4060 | Guido Trotter | raise RetryAgain()
|
362 | dfdc4060 | Guido Trotter | else:
|
363 | dfdc4060 | Guido Trotter | return result
|
364 | dfdc4060 | Guido Trotter | |
365 | dfdc4060 | Guido Trotter | def UpdateTimeout(self, timeout): |
366 | dfdc4060 | Guido Trotter | self.timeout = timeout
|
367 | dfdc4060 | Guido Trotter | |
368 | dfdc4060 | Guido Trotter | |
369 | dfdc4060 | Guido Trotter | def WaitForFdCondition(fdobj, event, timeout): |
370 | dfdc4060 | Guido Trotter | """Waits for a condition to occur on the socket.
|
371 | dfdc4060 | Guido Trotter |
|
372 | dfdc4060 | Guido Trotter | Retries until the timeout is expired, even if interrupted.
|
373 | dfdc4060 | Guido Trotter |
|
374 | dfdc4060 | Guido Trotter | @type fdobj: integer or object supporting a fileno() method
|
375 | dfdc4060 | Guido Trotter | @param fdobj: entity to wait for events on
|
376 | dfdc4060 | Guido Trotter | @type event: integer
|
377 | dfdc4060 | Guido Trotter | @param event: ORed condition (see select module)
|
378 | dfdc4060 | Guido Trotter | @type timeout: float or None
|
379 | dfdc4060 | Guido Trotter | @param timeout: Timeout in seconds
|
380 | dfdc4060 | Guido Trotter | @rtype: int or None
|
381 | dfdc4060 | Guido Trotter | @return: None for timeout, otherwise occured conditions
|
382 | dfdc4060 | Guido Trotter |
|
383 | dfdc4060 | Guido Trotter | """
|
384 | dfdc4060 | Guido Trotter | if timeout is not None: |
385 | dfdc4060 | Guido Trotter | retrywaiter = FdConditionWaiterHelper(timeout) |
386 | 1b429e2a | Iustin Pop | try:
|
387 | 1b429e2a | Iustin Pop | result = Retry(retrywaiter.Poll, RETRY_REMAINING_TIME, timeout, |
388 | 1b429e2a | Iustin Pop | args=(fdobj, event), wait_fn=retrywaiter.UpdateTimeout) |
389 | 1b429e2a | Iustin Pop | except RetryTimeout:
|
390 | 1b429e2a | Iustin Pop | result = None
|
391 | dfdc4060 | Guido Trotter | else:
|
392 | dfdc4060 | Guido Trotter | result = None
|
393 | dfdc4060 | Guido Trotter | while result is None: |
394 | dfdc4060 | Guido Trotter | result = SingleWaitForFdCondition(fdobj, event, timeout) |
395 | dfdc4060 | Guido Trotter | return result
|
396 | 2de64672 | Iustin Pop | |
397 | 2de64672 | Iustin Pop | |
398 | 2826b361 | Guido Trotter | def EnsureDaemon(name): |
399 | 2826b361 | Guido Trotter | """Check for and start daemon if not alive.
|
400 | 2826b361 | Guido Trotter |
|
401 | 2826b361 | Guido Trotter | """
|
402 | 2826b361 | Guido Trotter | result = RunCmd([constants.DAEMON_UTIL, "check-and-start", name])
|
403 | 2826b361 | Guido Trotter | if result.failed:
|
404 | 2826b361 | Guido Trotter | logging.error("Can't start daemon '%s', failure %s, output: %s",
|
405 | 2826b361 | Guido Trotter | name, result.fail_reason, result.output) |
406 | 2826b361 | Guido Trotter | return False |
407 | 2826b361 | Guido Trotter | |
408 | 2826b361 | Guido Trotter | return True |
409 | b330ac0b | Guido Trotter | |
410 | b330ac0b | Guido Trotter | |
411 | db147305 | Tom Limoncelli | def StopDaemon(name): |
412 | db147305 | Tom Limoncelli | """Stop daemon
|
413 | db147305 | Tom Limoncelli |
|
414 | db147305 | Tom Limoncelli | """
|
415 | db147305 | Tom Limoncelli | result = RunCmd([constants.DAEMON_UTIL, "stop", name])
|
416 | db147305 | Tom Limoncelli | if result.failed:
|
417 | db147305 | Tom Limoncelli | logging.error("Can't stop daemon '%s', failure %s, output: %s",
|
418 | db147305 | Tom Limoncelli | name, result.fail_reason, result.output) |
419 | db147305 | Tom Limoncelli | return False |
420 | db147305 | Tom Limoncelli | |
421 | db147305 | Tom Limoncelli | return True |
422 | db147305 | Tom Limoncelli | |
423 | db147305 | Tom Limoncelli | |
424 | 8d1a2a64 | Michael Hanselmann | def CheckVolumeGroupSize(vglist, vgname, minsize): |
425 | 8d1a2a64 | Michael Hanselmann | """Checks if the volume group list is valid.
|
426 | 8d1a2a64 | Michael Hanselmann |
|
427 | 58885d79 | Iustin Pop | The function will check if a given volume group is in the list of
|
428 | 58885d79 | Iustin Pop | volume groups and has a minimum size.
|
429 | 58885d79 | Iustin Pop |
|
430 | 58885d79 | Iustin Pop | @type vglist: dict
|
431 | 58885d79 | Iustin Pop | @param vglist: dictionary of volume group names and their size
|
432 | 58885d79 | Iustin Pop | @type vgname: str
|
433 | 58885d79 | Iustin Pop | @param vgname: the volume group we should check
|
434 | 58885d79 | Iustin Pop | @type minsize: int
|
435 | 58885d79 | Iustin Pop | @param minsize: the minimum size we accept
|
436 | 58885d79 | Iustin Pop | @rtype: None or str
|
437 | 58885d79 | Iustin Pop | @return: None for success, otherwise the error message
|
438 | 8d1a2a64 | Michael Hanselmann |
|
439 | 8d1a2a64 | Michael Hanselmann | """
|
440 | 8d1a2a64 | Michael Hanselmann | vgsize = vglist.get(vgname, None)
|
441 | 8d1a2a64 | Michael Hanselmann | if vgsize is None: |
442 | 8d1a2a64 | Michael Hanselmann | return "volume group '%s' missing" % vgname |
443 | 8d1a2a64 | Michael Hanselmann | elif vgsize < minsize:
|
444 | 8d1a2a64 | Michael Hanselmann | return ("volume group '%s' too small (%s MiB required, %d MiB found)" % |
445 | 8d1a2a64 | Michael Hanselmann | (vgname, minsize, vgsize)) |
446 | 8d1a2a64 | Michael Hanselmann | return None |
447 | 7996a135 | Iustin Pop | |
448 | 7996a135 | Iustin Pop | |
449 | 45bc5e4a | Michael Hanselmann | def SplitTime(value): |
450 | 739be818 | Michael Hanselmann | """Splits time as floating point number into a tuple.
|
451 | 739be818 | Michael Hanselmann |
|
452 | 45bc5e4a | Michael Hanselmann | @param value: Time in seconds
|
453 | 45bc5e4a | Michael Hanselmann | @type value: int or float
|
454 | 45bc5e4a | Michael Hanselmann | @return: Tuple containing (seconds, microseconds)
|
455 | 739be818 | Michael Hanselmann |
|
456 | 739be818 | Michael Hanselmann | """
|
457 | 45bc5e4a | Michael Hanselmann | (seconds, microseconds) = divmod(int(value * 1000000), 1000000) |
458 | 45bc5e4a | Michael Hanselmann | |
459 | 45bc5e4a | Michael Hanselmann | assert 0 <= seconds, \ |
460 | 45bc5e4a | Michael Hanselmann | "Seconds must be larger than or equal to 0, but are %s" % seconds
|
461 | 45bc5e4a | Michael Hanselmann | assert 0 <= microseconds <= 999999, \ |
462 | 45bc5e4a | Michael Hanselmann | "Microseconds must be 0-999999, but are %s" % microseconds
|
463 | 45bc5e4a | Michael Hanselmann | |
464 | 45bc5e4a | Michael Hanselmann | return (int(seconds), int(microseconds)) |
465 | 739be818 | Michael Hanselmann | |
466 | 739be818 | Michael Hanselmann | |
467 | 739be818 | Michael Hanselmann | def MergeTime(timetuple): |
468 | 739be818 | Michael Hanselmann | """Merges a tuple into time as a floating point number.
|
469 | 739be818 | Michael Hanselmann |
|
470 | 45bc5e4a | Michael Hanselmann | @param timetuple: Time as tuple, (seconds, microseconds)
|
471 | 739be818 | Michael Hanselmann | @type timetuple: tuple
|
472 | 739be818 | Michael Hanselmann | @return: Time as a floating point number expressed in seconds
|
473 | 739be818 | Michael Hanselmann |
|
474 | 739be818 | Michael Hanselmann | """
|
475 | 45bc5e4a | Michael Hanselmann | (seconds, microseconds) = timetuple |
476 | 739be818 | Michael Hanselmann | |
477 | 45bc5e4a | Michael Hanselmann | assert 0 <= seconds, \ |
478 | 45bc5e4a | Michael Hanselmann | "Seconds must be larger than or equal to 0, but are %s" % seconds
|
479 | 45bc5e4a | Michael Hanselmann | assert 0 <= microseconds <= 999999, \ |
480 | 45bc5e4a | Michael Hanselmann | "Microseconds must be 0-999999, but are %s" % microseconds
|
481 | 739be818 | Michael Hanselmann | |
482 | 45bc5e4a | Michael Hanselmann | return float(seconds) + (float(microseconds) * 0.000001) |
483 | 739be818 | Michael Hanselmann | |
484 | 739be818 | Michael Hanselmann | |
485 | 691c81b7 | Michael Hanselmann | def FindMatch(data, name): |
486 | 691c81b7 | Michael Hanselmann | """Tries to find an item in a dictionary matching a name.
|
487 | 691c81b7 | Michael Hanselmann |
|
488 | 691c81b7 | Michael Hanselmann | Callers have to ensure the data names aren't contradictory (e.g. a regexp
|
489 | 691c81b7 | Michael Hanselmann | that matches a string). If the name isn't a direct key, all regular
|
490 | 691c81b7 | Michael Hanselmann | expression objects in the dictionary are matched against it.
|
491 | 691c81b7 | Michael Hanselmann |
|
492 | 691c81b7 | Michael Hanselmann | @type data: dict
|
493 | 691c81b7 | Michael Hanselmann | @param data: Dictionary containing data
|
494 | 691c81b7 | Michael Hanselmann | @type name: string
|
495 | 691c81b7 | Michael Hanselmann | @param name: Name to look for
|
496 | 691c81b7 | Michael Hanselmann | @rtype: tuple; (value in dictionary, matched groups as list)
|
497 | 691c81b7 | Michael Hanselmann |
|
498 | 691c81b7 | Michael Hanselmann | """
|
499 | 691c81b7 | Michael Hanselmann | if name in data: |
500 | 691c81b7 | Michael Hanselmann | return (data[name], [])
|
501 | 691c81b7 | Michael Hanselmann | |
502 | 691c81b7 | Michael Hanselmann | for key, value in data.items(): |
503 | 691c81b7 | Michael Hanselmann | # Regex objects
|
504 | 691c81b7 | Michael Hanselmann | if hasattr(key, "match"): |
505 | 691c81b7 | Michael Hanselmann | m = key.match(name) |
506 | 691c81b7 | Michael Hanselmann | if m:
|
507 | 691c81b7 | Michael Hanselmann | return (value, list(m.groups())) |
508 | 691c81b7 | Michael Hanselmann | |
509 | 691c81b7 | Michael Hanselmann | return None |
510 | 691c81b7 | Michael Hanselmann | |
511 | 691c81b7 | Michael Hanselmann | |
512 | 1b045f5d | Balazs Lecz | def GetMounts(filename=constants.PROC_MOUNTS): |
513 | 1b045f5d | Balazs Lecz | """Returns the list of mounted filesystems.
|
514 | 1b045f5d | Balazs Lecz |
|
515 | 1b045f5d | Balazs Lecz | This function is Linux-specific.
|
516 | 1b045f5d | Balazs Lecz |
|
517 | 1b045f5d | Balazs Lecz | @param filename: path of mounts file (/proc/mounts by default)
|
518 | 1b045f5d | Balazs Lecz | @rtype: list of tuples
|
519 | 1b045f5d | Balazs Lecz | @return: list of mount entries (device, mountpoint, fstype, options)
|
520 | 1b045f5d | Balazs Lecz |
|
521 | 1b045f5d | Balazs Lecz | """
|
522 | 1b045f5d | Balazs Lecz | # TODO(iustin): investigate non-Linux options (e.g. via mount output)
|
523 | 1b045f5d | Balazs Lecz | data = [] |
524 | 1b045f5d | Balazs Lecz | mountlines = ReadFile(filename).splitlines() |
525 | 1b045f5d | Balazs Lecz | for line in mountlines: |
526 | 1b045f5d | Balazs Lecz | device, mountpoint, fstype, options, _ = line.split(None, 4) |
527 | 1b045f5d | Balazs Lecz | data.append((device, mountpoint, fstype, options)) |
528 | 1b045f5d | Balazs Lecz | |
529 | 1b045f5d | Balazs Lecz | return data
|
530 | 1b045f5d | Balazs Lecz | |
531 | 1b045f5d | Balazs Lecz | |
532 | 451575de | Guido Trotter | def SignalHandled(signums): |
533 | 451575de | Guido Trotter | """Signal Handled decoration.
|
534 | 451575de | Guido Trotter |
|
535 | 451575de | Guido Trotter | This special decorator installs a signal handler and then calls the target
|
536 | 451575de | Guido Trotter | function. The function must accept a 'signal_handlers' keyword argument,
|
537 | 451575de | Guido Trotter | which will contain a dict indexed by signal number, with SignalHandler
|
538 | 451575de | Guido Trotter | objects as values.
|
539 | 451575de | Guido Trotter |
|
540 | 451575de | Guido Trotter | The decorator can be safely stacked with iself, to handle multiple signals
|
541 | 451575de | Guido Trotter | with different handlers.
|
542 | 451575de | Guido Trotter |
|
543 | 451575de | Guido Trotter | @type signums: list
|
544 | 451575de | Guido Trotter | @param signums: signals to intercept
|
545 | 451575de | Guido Trotter |
|
546 | 451575de | Guido Trotter | """
|
547 | 451575de | Guido Trotter | def wrap(fn): |
548 | 451575de | Guido Trotter | def sig_function(*args, **kwargs): |
549 | 451575de | Guido Trotter | assert 'signal_handlers' not in kwargs or \ |
550 | 451575de | Guido Trotter | kwargs['signal_handlers'] is None or \ |
551 | 451575de | Guido Trotter | isinstance(kwargs['signal_handlers'], dict), \ |
552 | 451575de | Guido Trotter | "Wrong signal_handlers parameter in original function call"
|
553 | 451575de | Guido Trotter | if 'signal_handlers' in kwargs and kwargs['signal_handlers'] is not None: |
554 | 451575de | Guido Trotter | signal_handlers = kwargs['signal_handlers']
|
555 | 451575de | Guido Trotter | else:
|
556 | 451575de | Guido Trotter | signal_handlers = {} |
557 | 451575de | Guido Trotter | kwargs['signal_handlers'] = signal_handlers
|
558 | 451575de | Guido Trotter | sighandler = SignalHandler(signums) |
559 | 451575de | Guido Trotter | try:
|
560 | 451575de | Guido Trotter | for sig in signums: |
561 | 451575de | Guido Trotter | signal_handlers[sig] = sighandler |
562 | 451575de | Guido Trotter | return fn(*args, **kwargs)
|
563 | 451575de | Guido Trotter | finally:
|
564 | 451575de | Guido Trotter | sighandler.Reset() |
565 | 451575de | Guido Trotter | return sig_function
|
566 | 451575de | Guido Trotter | return wrap
|
567 | 451575de | Guido Trotter | |
568 | 451575de | Guido Trotter | |
569 | b9768937 | Michael Hanselmann | class SignalWakeupFd(object): |
570 | b9768937 | Michael Hanselmann | try:
|
571 | b9768937 | Michael Hanselmann | # This is only supported in Python 2.5 and above (some distributions
|
572 | b9768937 | Michael Hanselmann | # backported it to Python 2.4)
|
573 | b9768937 | Michael Hanselmann | _set_wakeup_fd_fn = signal.set_wakeup_fd |
574 | b9768937 | Michael Hanselmann | except AttributeError: |
575 | b9768937 | Michael Hanselmann | # Not supported
|
576 | b9768937 | Michael Hanselmann | def _SetWakeupFd(self, _): # pylint: disable-msg=R0201 |
577 | b9768937 | Michael Hanselmann | return -1 |
578 | b9768937 | Michael Hanselmann | else:
|
579 | b9768937 | Michael Hanselmann | def _SetWakeupFd(self, fd): |
580 | b9768937 | Michael Hanselmann | return self._set_wakeup_fd_fn(fd) |
581 | b9768937 | Michael Hanselmann | |
582 | b9768937 | Michael Hanselmann | def __init__(self): |
583 | b9768937 | Michael Hanselmann | """Initializes this class.
|
584 | b9768937 | Michael Hanselmann |
|
585 | b9768937 | Michael Hanselmann | """
|
586 | b9768937 | Michael Hanselmann | (read_fd, write_fd) = os.pipe() |
587 | b9768937 | Michael Hanselmann | |
588 | b9768937 | Michael Hanselmann | # Once these succeeded, the file descriptors will be closed automatically.
|
589 | b9768937 | Michael Hanselmann | # Buffer size 0 is important, otherwise .read() with a specified length
|
590 | b9768937 | Michael Hanselmann | # might buffer data and the file descriptors won't be marked readable.
|
591 | b9768937 | Michael Hanselmann | self._read_fh = os.fdopen(read_fd, "r", 0) |
592 | b9768937 | Michael Hanselmann | self._write_fh = os.fdopen(write_fd, "w", 0) |
593 | b9768937 | Michael Hanselmann | |
594 | b9768937 | Michael Hanselmann | self._previous = self._SetWakeupFd(self._write_fh.fileno()) |
595 | b9768937 | Michael Hanselmann | |
596 | b9768937 | Michael Hanselmann | # Utility functions
|
597 | b9768937 | Michael Hanselmann | self.fileno = self._read_fh.fileno |
598 | b9768937 | Michael Hanselmann | self.read = self._read_fh.read |
599 | b9768937 | Michael Hanselmann | |
600 | b9768937 | Michael Hanselmann | def Reset(self): |
601 | b9768937 | Michael Hanselmann | """Restores the previous wakeup file descriptor.
|
602 | b9768937 | Michael Hanselmann |
|
603 | b9768937 | Michael Hanselmann | """
|
604 | b9768937 | Michael Hanselmann | if hasattr(self, "_previous") and self._previous is not None: |
605 | b9768937 | Michael Hanselmann | self._SetWakeupFd(self._previous) |
606 | b9768937 | Michael Hanselmann | self._previous = None |
607 | b9768937 | Michael Hanselmann | |
608 | b9768937 | Michael Hanselmann | def Notify(self): |
609 | b9768937 | Michael Hanselmann | """Notifies the wakeup file descriptor.
|
610 | b9768937 | Michael Hanselmann |
|
611 | b9768937 | Michael Hanselmann | """
|
612 | b9768937 | Michael Hanselmann | self._write_fh.write("\0") |
613 | b9768937 | Michael Hanselmann | |
614 | b9768937 | Michael Hanselmann | def __del__(self): |
615 | b9768937 | Michael Hanselmann | """Called before object deletion.
|
616 | b9768937 | Michael Hanselmann |
|
617 | b9768937 | Michael Hanselmann | """
|
618 | b9768937 | Michael Hanselmann | self.Reset()
|
619 | b9768937 | Michael Hanselmann | |
620 | b9768937 | Michael Hanselmann | |
621 | de499029 | Michael Hanselmann | class SignalHandler(object): |
622 | de499029 | Michael Hanselmann | """Generic signal handler class.
|
623 | de499029 | Michael Hanselmann |
|
624 | 58885d79 | Iustin Pop | It automatically restores the original handler when deconstructed or
|
625 | 58885d79 | Iustin Pop | when L{Reset} is called. You can either pass your own handler
|
626 | 58885d79 | Iustin Pop | function in or query the L{called} attribute to detect whether the
|
627 | 58885d79 | Iustin Pop | signal was sent.
|
628 | 58885d79 | Iustin Pop |
|
629 | 58885d79 | Iustin Pop | @type signum: list
|
630 | 58885d79 | Iustin Pop | @ivar signum: the signals we handle
|
631 | 58885d79 | Iustin Pop | @type called: boolean
|
632 | 58885d79 | Iustin Pop | @ivar called: tracks whether any of the signals have been raised
|
633 | de499029 | Michael Hanselmann |
|
634 | de499029 | Michael Hanselmann | """
|
635 | b9768937 | Michael Hanselmann | def __init__(self, signum, handler_fn=None, wakeup=None): |
636 | de499029 | Michael Hanselmann | """Constructs a new SignalHandler instance.
|
637 | de499029 | Michael Hanselmann |
|
638 | 58885d79 | Iustin Pop | @type signum: int or list of ints
|
639 | de499029 | Michael Hanselmann | @param signum: Single signal number or set of signal numbers
|
640 | 92b61ec7 | Michael Hanselmann | @type handler_fn: callable
|
641 | 92b61ec7 | Michael Hanselmann | @param handler_fn: Signal handling function
|
642 | de499029 | Michael Hanselmann |
|
643 | de499029 | Michael Hanselmann | """
|
644 | 92b61ec7 | Michael Hanselmann | assert handler_fn is None or callable(handler_fn) |
645 | 92b61ec7 | Michael Hanselmann | |
646 | 6c52849e | Guido Trotter | self.signum = set(signum) |
647 | de499029 | Michael Hanselmann | self.called = False |
648 | de499029 | Michael Hanselmann | |
649 | 92b61ec7 | Michael Hanselmann | self._handler_fn = handler_fn
|
650 | b9768937 | Michael Hanselmann | self._wakeup = wakeup
|
651 | 92b61ec7 | Michael Hanselmann | |
652 | de499029 | Michael Hanselmann | self._previous = {}
|
653 | de499029 | Michael Hanselmann | try:
|
654 | de499029 | Michael Hanselmann | for signum in self.signum: |
655 | de499029 | Michael Hanselmann | # Setup handler
|
656 | de499029 | Michael Hanselmann | prev_handler = signal.signal(signum, self._HandleSignal)
|
657 | de499029 | Michael Hanselmann | try:
|
658 | de499029 | Michael Hanselmann | self._previous[signum] = prev_handler
|
659 | de499029 | Michael Hanselmann | except:
|
660 | de499029 | Michael Hanselmann | # Restore previous handler
|
661 | de499029 | Michael Hanselmann | signal.signal(signum, prev_handler) |
662 | de499029 | Michael Hanselmann | raise
|
663 | de499029 | Michael Hanselmann | except:
|
664 | de499029 | Michael Hanselmann | # Reset all handlers
|
665 | de499029 | Michael Hanselmann | self.Reset()
|
666 | de499029 | Michael Hanselmann | # Here we have a race condition: a handler may have already been called,
|
667 | de499029 | Michael Hanselmann | # but there's not much we can do about it at this point.
|
668 | de499029 | Michael Hanselmann | raise
|
669 | de499029 | Michael Hanselmann | |
670 | de499029 | Michael Hanselmann | def __del__(self): |
671 | de499029 | Michael Hanselmann | self.Reset()
|
672 | de499029 | Michael Hanselmann | |
673 | de499029 | Michael Hanselmann | def Reset(self): |
674 | de499029 | Michael Hanselmann | """Restore previous handler.
|
675 | de499029 | Michael Hanselmann |
|
676 | 58885d79 | Iustin Pop | This will reset all the signals to their previous handlers.
|
677 | 58885d79 | Iustin Pop |
|
678 | de499029 | Michael Hanselmann | """
|
679 | de499029 | Michael Hanselmann | for signum, prev_handler in self._previous.items(): |
680 | de499029 | Michael Hanselmann | signal.signal(signum, prev_handler) |
681 | de499029 | Michael Hanselmann | # If successful, remove from dict
|
682 | de499029 | Michael Hanselmann | del self._previous[signum] |
683 | de499029 | Michael Hanselmann | |
684 | de499029 | Michael Hanselmann | def Clear(self): |
685 | 58885d79 | Iustin Pop | """Unsets the L{called} flag.
|
686 | de499029 | Michael Hanselmann |
|
687 | de499029 | Michael Hanselmann | This function can be used in case a signal may arrive several times.
|
688 | de499029 | Michael Hanselmann |
|
689 | de499029 | Michael Hanselmann | """
|
690 | de499029 | Michael Hanselmann | self.called = False |
691 | de499029 | Michael Hanselmann | |
692 | 92b61ec7 | Michael Hanselmann | def _HandleSignal(self, signum, frame): |
693 | de499029 | Michael Hanselmann | """Actual signal handling function.
|
694 | de499029 | Michael Hanselmann |
|
695 | de499029 | Michael Hanselmann | """
|
696 | de499029 | Michael Hanselmann | # This is not nice and not absolutely atomic, but it appears to be the only
|
697 | de499029 | Michael Hanselmann | # solution in Python -- there are no atomic types.
|
698 | de499029 | Michael Hanselmann | self.called = True |
699 | a2d2e1a7 | Iustin Pop | |
700 | b9768937 | Michael Hanselmann | if self._wakeup: |
701 | b9768937 | Michael Hanselmann | # Notify whoever is interested in signals
|
702 | b9768937 | Michael Hanselmann | self._wakeup.Notify()
|
703 | b9768937 | Michael Hanselmann | |
704 | 92b61ec7 | Michael Hanselmann | if self._handler_fn: |
705 | 92b61ec7 | Michael Hanselmann | self._handler_fn(signum, frame)
|
706 | 92b61ec7 | Michael Hanselmann | |
707 | a2d2e1a7 | Iustin Pop | |
708 | a2d2e1a7 | Iustin Pop | class FieldSet(object): |
709 | a2d2e1a7 | Iustin Pop | """A simple field set.
|
710 | a2d2e1a7 | Iustin Pop |
|
711 | a2d2e1a7 | Iustin Pop | Among the features are:
|
712 | a2d2e1a7 | Iustin Pop | - checking if a string is among a list of static string or regex objects
|
713 | a2d2e1a7 | Iustin Pop | - checking if a whole list of string matches
|
714 | a2d2e1a7 | Iustin Pop | - returning the matching groups from a regex match
|
715 | a2d2e1a7 | Iustin Pop |
|
716 | a2d2e1a7 | Iustin Pop | Internally, all fields are held as regular expression objects.
|
717 | a2d2e1a7 | Iustin Pop |
|
718 | a2d2e1a7 | Iustin Pop | """
|
719 | a2d2e1a7 | Iustin Pop | def __init__(self, *items): |
720 | a2d2e1a7 | Iustin Pop | self.items = [re.compile("^%s$" % value) for value in items] |
721 | a2d2e1a7 | Iustin Pop | |
722 | a2d2e1a7 | Iustin Pop | def Extend(self, other_set): |
723 | a2d2e1a7 | Iustin Pop | """Extend the field set with the items from another one"""
|
724 | a2d2e1a7 | Iustin Pop | self.items.extend(other_set.items)
|
725 | a2d2e1a7 | Iustin Pop | |
726 | a2d2e1a7 | Iustin Pop | def Matches(self, field): |
727 | a2d2e1a7 | Iustin Pop | """Checks if a field matches the current set
|
728 | a2d2e1a7 | Iustin Pop |
|
729 | a2d2e1a7 | Iustin Pop | @type field: str
|
730 | a2d2e1a7 | Iustin Pop | @param field: the string to match
|
731 | 6c881c52 | Iustin Pop | @return: either None or a regular expression match object
|
732 | a2d2e1a7 | Iustin Pop |
|
733 | a2d2e1a7 | Iustin Pop | """
|
734 | a2d2e1a7 | Iustin Pop | for m in itertools.ifilter(None, (val.match(field) for val in self.items)): |
735 | a2d2e1a7 | Iustin Pop | return m
|
736 | 6c881c52 | Iustin Pop | return None |
737 | a2d2e1a7 | Iustin Pop | |
738 | a2d2e1a7 | Iustin Pop | def NonMatching(self, items): |
739 | a2d2e1a7 | Iustin Pop | """Returns the list of fields not matching the current set
|
740 | a2d2e1a7 | Iustin Pop |
|
741 | a2d2e1a7 | Iustin Pop | @type items: list
|
742 | a2d2e1a7 | Iustin Pop | @param items: the list of fields to check
|
743 | a2d2e1a7 | Iustin Pop | @rtype: list
|
744 | a2d2e1a7 | Iustin Pop | @return: list of non-matching fields
|
745 | a2d2e1a7 | Iustin Pop |
|
746 | a2d2e1a7 | Iustin Pop | """
|
747 | a2d2e1a7 | Iustin Pop | return [val for val in items if not self.Matches(val)] |