vcs.maemo.org Git - dbuscron/blob - dbuscron/parser.py

   1 # encoding: utf-8
   2 from __future__ import with_statement
   3 import os
   4 import re
   5 from dbuscron.bus import DbusBus
   6
   7 def unescape_():
   8     h = '[0-9A-Fa-f]'
   9     r = re.compile(r'\\x('+h+r'{2})|\\u('+h+'{4})')
  10
  11     def unescape(value):
  12         if not (value and
  13                 (r'\x' in value or r'\u' in value)):
  14             return value
  15
  16         return r.sub(
  17             lambda m: chr(int(m.group(1), 16))
  18                 if m.group(1) is not None else
  19                     unichr(int(m.group(2), 16))
  20                         .encode('utf-8'),\
  21             value)
  22     return unescape
  23 unescape = unescape_()
  24
  25 def product(*args):
  26     if args:
  27         head, tail = args[0], args[1:]
  28         for h in head:
  29             for t in product(*tail):
  30                 yield (h,) + t
  31
  32     else:
  33         yield ()
  34
  35 class CrontabParserError(SyntaxError):
  36     def __init__(self, message, lineno, expected=None):
  37         if expected:
  38             if isinstance(expected, (tuple, list)):
  39                 exp = ' (expected %s or %s)' % (', '.join(expected[:-1]), expected[-1])
  40         else:
  41             exp = ''
  42
  43         msg = '%s%s at line %d' % (message, exp, lineno)
  44
  45         SyntaxError.__init__(self, msg)
  46
  47 class CrontabParser(object):
  48     __fields_sep = re.compile(r'\s+')
  49     __envvar_sep = re.compile(r'\s*=\s*')
  50     __fields_chk = {
  51             'bus_'         : None,
  52             'type_'        : ('signal', 'method_call', 'method_return', 'error'),
  53             'sender_'      : None,
  54             'interface_'   : re.compile(r'^[a-zA-Z][a-zA-Z0-9_.]+$'),
  55             'path_'        : re.compile(r'^/[a-zA-Z0-9_/]+$'),
  56             'member_'      : re.compile(r'^[a-zA-Z][a-zA-Z0-9_]+$'),
  57             'destination_' : None,
  58             'args_'        : None,
  59             }
  60     __fields = [
  61             'bus_',
  62             'type_',
  63             'sender_',
  64             'interface_',
  65             'path_',
  66             'member_',
  67             'destination_',
  68             'args_',
  69             ]
  70
  71     def __init__(self, fname):
  72         self.__bus = DbusBus()
  73         self.__filename = fname
  74         self.__environ = dict()
  75
  76     @property
  77     def environ(self):
  78         return self.__environ
  79
  80     def _iterate_file(self, filename):
  81         # bus type sender interface path member destination args command
  82         lineno = 0
  83         with open(filename) as f:
  84             for line in f:
  85                 lineno += 1
  86                 line = line.strip()
  87
  88                 if not line or line.startswith('#'):
  89                     continue
  90
  91                 parts = self.__fields_sep.split(line, 8)
  92                 if len(parts) < 9:
  93                     parts = self.__envvar_sep.split(line, 1)
  94                     if len(parts) == 2:
  95                         self.__environ[parts[0]] = parts[1]
  96                         continue
  97
  98                     raise CrontabParserError('Unexpected number of records', lineno)
  99
 100                 rule = [('s', 'S'), self.__fields_chk['type_'], (None,), (None,), (None,), (None,), (None,), (None,)]
 101
 102                 for p in range(0, 8):
 103                     if parts[p] != '*':
 104                         rule[p] = parts[p].split(',')
 105
 106                 command = parts[8]
 107
 108                 for r in product(*rule):
 109                     r = list(r)
 110                     if r[0] == 'S':
 111                         r[0] = self.__bus.system
 112                     elif r[0] == 's':
 113                         r[0] = self.__bus.session
 114                     else:
 115                         raise CrontabParserError('Unexpected bus value', lineno, expected=('S', 's', '*'))
 116
 117                     if r[7]:
 118                         r[7] = map(unescape, r[7].split(';'))
 119
 120                     ruled = dict()
 121                     for i, f in enumerate(self.__fields):
 122                         if r[i] is not None and self.__fields_chk[f]:
 123                             if isinstance(self.__fields_chk[f], tuple):
 124                                 if r[i] not in self.__fields_chk[f]:
 125                                     raise CrontabParserError('Unexpected %s value' % (f.strip('_')), lineno,
 126                                             expected=self.__fields_chk[f])
 127                             else:
 128                                 if not self.__fields_chk[f].match(r[i]):
 129                                     raise CrontabParserError('Incorrect %s value' % (f.strip('_')), lineno)
 130                         ruled[f] = r[i]
 131
 132                     yield ruled, command
 133
 134     def __iter__(self):
 135         return self._iterate_file(self.__filename)
 136
 137 class DirectoryParser(CrontabParser):
 138
 139     def __init__(self, dirname, recursive=False):
 140         self.__dirname = dirname
 141         self.__recursive = recursive
 142         super(DirectoryParser, self).__init__(None)
 143
 144     def _dirwalker_plain(self):
 145         for i in os.listdir(self.__dirname):
 146             if os.path.isfile(i):
 147                 yield i
 148
 149     def _dirwalker_recursive(self):
 150         for r, d, f in os.walk(self.__dirname):
 151             for i in f:
 152                 yield i
 153
 154     def __iter__(self):
 155
 156         if self.__recursive:
 157             dirwalker = self._dirwalker_recursive
 158         else:
 159             dirwalker = self._dirwalker_plain
 160
 161         for fname in dirwalker():
 162             fullname = os.path.join(self.__dirname, fname)
 163             self.__filename = fullname
 164             for item in self._iterate_file(fullname):
 165                 yield item
 166
 167 def OptionsParser(args=None, help=u'', **opts):
 168
 169     from optparse import OptionParser
 170     import dbuscron
 171     parser = OptionParser(usage=help, version="%prog " + dbuscron.__version__)
 172     for opt, desc in opts.iteritems():
 173         names = desc.pop('names')
 174         desc['dest'] = opt
 175         parser.add_option(*names, **desc)
 176
 177     return parser.parse_args(args)[0]
 178