source/tdb/swig/Tdb.py

   1 """Provide a more Pythonic and object-oriented interface to tdb."""
   2
   3 #
   4 # Swig interface to Samba
   5 #
   6 # Copyright (C) Tim Potter 2006
   7 #
   8 # This program is free software; you can redistribute it and/or modify
   9 # it under the terms of the GNU General Public License as published by
  10 # the Free Software Foundation; either version 2 of the License, or
  11 # (at your option) any later version.
  12 #
  13 # This program is distributed in the hope that it will be useful,
  14 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 # GNU General Public License for more details.
  17 #
  18 # You should have received a copy of the GNU General Public License
  19 # along with this program; if not, write to the Free Software
  20 # Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  21 #
  22
  23 import os
  24 from tdb import *
  25
  26 # Open flags
  27
  28 DEFAULT        = TDB_DEFAULT
  29 CLEAR_IF_FIRST = TDB_CLEAR_IF_FIRST
  30 INTERNAL       = TDB_INTERNAL
  31 NOLOCK         = TDB_NOLOCK
  32 NOMMAP         = TDB_NOMMAP
  33
  34 # Class representing a TDB file
  35
  36 class Tdb:
  37
  38     # Create and destroy Tdb objects
  39
  40     def __init__(self, name, hash_size = 0, flags = TDB_DEFAULT,
  41                  open_flags = os.O_RDWR | os.O_CREAT, mode = 0600):
  42         self.tdb = tdb_open(name, hash_size, flags, open_flags, mode)
  43         if self.tdb is None:
  44             raise IOError, tdb_errorstr(self.tdb)
  45
  46     def __del__(self):
  47         self.close()
  48
  49     def close(self):
  50         if hasattr(self, 'tdb') and self.tdb is not None:
  51             if tdb_close(self.tdb) == -1:
  52                 raise IOError, tdb_errorstr(self.tdb)
  53             self.tdb = None
  54
  55     # Random access to keys, values
  56
  57     def __getitem__(self, key):
  58         result = tdb_fetch(self.tdb, key)
  59         if result is None:
  60             raise KeyError, '%s: %s' % (key, tdb_errorstr(self.tdb))
  61         return result
  62
  63     def __setitem__(self, key, item):
  64         if tdb_store(self.tdb, key, item) == -1:
  65             raise IOError, tdb_errorstr(self.tdb)
  66
  67     def __delitem__(self, key):
  68         if not tdb_exists(self.tdb, key):
  69             raise KeyError, '%s: %s' % (key, tdb_errorstr(self.tdb))
  70         tdb_delete(self.tdb, key)
  71
  72     def has_key(self, key):
  73         return tdb_exists(self.tdb, key)
  74
  75     # Tdb iterator
  76
  77     class TdbIterator:
  78         def __init__(self, tdb):
  79             self.tdb = tdb
  80             self.key = None
  81
  82         def __iter__(self):
  83             return self
  84
  85         def next(self):
  86             if self.key is None:
  87                 self.key = tdb_firstkey(self.tdb)
  88                 if self.key is None:
  89                     raise StopIteration
  90                 return self.key
  91             else:
  92                 self.key = tdb_nextkey(self.tdb, self.key)
  93                 if self.key is None:
  94                     raise StopIteration
  95                 return self.key
  96
  97     def __iter__(self):
  98         return Tdb.TdbIterator(self.tdb)
  99
 100     # Implement other dict functions using TdbIterator
 101
 102     def keys(self):
 103         return [k for k in iter(self)]
 104
 105     def values(self):
 106         return [self[k] for k in iter(self)]
 107
 108     def items(self):
 109         return [(k, self[k]) for k in iter(self)]
 110
 111     def __len__(self):
 112         return len(self.keys())
 113
 114     def clear(self):
 115         for k in iter(self):
 116             del(self[k])