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Diffstat (limited to 'Lib/bsddb/__init__.py')
| -rw-r--r-- | Lib/bsddb/__init__.py | 237 |
1 files changed, 237 insertions, 0 deletions
diff --git a/Lib/bsddb/__init__.py b/Lib/bsddb/__init__.py new file mode 100644 index 0000000..a2d820c --- /dev/null +++ b/Lib/bsddb/__init__.py @@ -0,0 +1,237 @@ +#---------------------------------------------------------------------- +# Copyright (c) 1999-2001, Digital Creations, Fredericksburg, VA, USA +# and Andrew Kuchling. All rights reserved. +# +# Redistribution and use in source and binary forms, with or without +# modification, are permitted provided that the following conditions are +# met: +# +# o Redistributions of source code must retain the above copyright +# notice, this list of conditions, and the disclaimer that follows. +# +# o Redistributions in binary form must reproduce the above copyright +# notice, this list of conditions, and the following disclaimer in +# the documentation and/or other materials provided with the +# distribution. +# +# o Neither the name of Digital Creations nor the names of its +# contributors may be used to endorse or promote products derived +# from this software without specific prior written permission. +# +# THIS SOFTWARE IS PROVIDED BY DIGITAL CREATIONS AND CONTRIBUTORS *AS +# IS* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED +# TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A +# PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL DIGITAL +# CREATIONS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, +# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, +# BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS +# OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND +# ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR +# TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE +# USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH +# DAMAGE. +#---------------------------------------------------------------------- + + +""" +This package initialization module provides a compatibility interface +that should enable bsddb3 to be a near drop-in replacement for the original +old bsddb module. The functions and classes provided here are all +wrappers around the new functionality provided in the bsddb3.db module. + +People interested in the more advanced capabilites of Berkeley DB 3.x +should use the bsddb3.db module directly. +""" + +import _bsddb +# bsddb3 calls it _db +_db = _bsddb +__version__ = _db.__version__ + +error = _db.DBError # So bsddb3.error will mean something... + +#---------------------------------------------------------------------- + + +class _DBWithCursor: + """ + A simple wrapper around DB that makes it look like the bsddbobject in + the old module. It uses a cursor as needed to provide DB traversal. + """ + def __init__(self, db): + self.db = db + self.dbc = None + self.db.set_get_returns_none(0) + + def __del__(self): + self.close() + + def _checkCursor(self): + if self.dbc is None: + self.dbc = self.db.cursor() + + def _checkOpen(self): + if self.db is None: + raise error, "BSDDB object has already been closed" + + def isOpen(self): + return self.db is not None + + def __len__(self): + self._checkOpen() + return len(self.db) + + def __getitem__(self, key): + self._checkOpen() + return self.db[key] + + def __setitem__(self, key, value): + self._checkOpen() + self.db[key] = value + + def __delitem__(self, key): + self._checkOpen() + del self.db[key] + + def close(self): + if self.dbc is not None: + self.dbc.close() + v = 0 + if self.db is not None: + v = self.db.close() + self.dbc = None + self.db = None + return v + + def keys(self): + self._checkOpen() + return self.db.keys() + + def has_key(self, key): + self._checkOpen() + return self.db.has_key(key) + + def set_location(self, key): + self._checkOpen() + self._checkCursor() + return self.dbc.set(key) + + def next(self): + self._checkOpen() + self._checkCursor() + rv = self.dbc.next() + return rv + + def previous(self): + self._checkOpen() + self._checkCursor() + rv = self.dbc.prev() + return rv + + def first(self): + self._checkOpen() + self._checkCursor() + rv = self.dbc.first() + return rv + + def last(self): + self._checkOpen() + self._checkCursor() + rv = self.dbc.last() + return rv + + def sync(self): + self._checkOpen() + return self.db.sync() + + +#---------------------------------------------------------------------- +# Compatibility object factory functions + +def hashopen(file, flag='c', mode=0666, pgsize=None, ffactor=None, nelem=None, + cachesize=None, lorder=None, hflags=0): + + flags = _checkflag(flag) + d = _db.DB() + d.set_flags(hflags) + if cachesize is not None: d.set_cachesize(0, cachesize) + if pgsize is not None: d.set_pagesize(pgsize) + if lorder is not None: d.set_lorder(lorder) + if ffactor is not None: d.set_h_ffactor(ffactor) + if nelem is not None: d.set_h_nelem(nelem) + d.open(file, _db.DB_HASH, flags, mode) + return _DBWithCursor(d) + +#---------------------------------------------------------------------- + +def btopen(file, flag='c', mode=0666, + btflags=0, cachesize=None, maxkeypage=None, minkeypage=None, + pgsize=None, lorder=None): + + flags = _checkflag(flag) + d = _db.DB() + if cachesize is not None: d.set_cachesize(0, cachesize) + if pgsize is not None: d.set_pagesize(pgsize) + if lorder is not None: d.set_lorder(lorder) + d.set_flags(btflags) + if minkeypage is not None: d.set_bt_minkey(minkeypage) + if maxkeypage is not None: d.set_bt_maxkey(maxkeypage) + d.open(file, _db.DB_BTREE, flags, mode) + return _DBWithCursor(d) + +#---------------------------------------------------------------------- + + +def rnopen(file, flag='c', mode=0666, + rnflags=0, cachesize=None, pgsize=None, lorder=None, + rlen=None, delim=None, source=None, pad=None): + + flags = _checkflag(flag) + d = _db.DB() + if cachesize is not None: d.set_cachesize(0, cachesize) + if pgsize is not None: d.set_pagesize(pgsize) + if lorder is not None: d.set_lorder(lorder) + d.set_flags(rnflags) + if delim is not None: d.set_re_delim(delim) + if rlen is not None: d.set_re_len(rlen) + if source is not None: d.set_re_source(source) + if pad is not None: d.set_re_pad(pad) + d.open(file, _db.DB_RECNO, flags, mode) + return _DBWithCursor(d) + +#---------------------------------------------------------------------- + + +def _checkflag(flag): + if flag == 'r': + flags = _db.DB_RDONLY + elif flag == 'rw': + flags = 0 + elif flag == 'w': + flags = _db.DB_CREATE + elif flag == 'c': + flags = _db.DB_CREATE + elif flag == 'n': + flags = _db.DB_CREATE | _db.DB_TRUNCATE + else: + raise error, "flags should be one of 'r', 'w', 'c' or 'n'" + return flags | _db.DB_THREAD + +#---------------------------------------------------------------------- + + +# This is a silly little hack that allows apps to continue to use the +# DB_THREAD flag even on systems without threads without freaking out +# BerkeleyDB. +# +# This assumes that if Python was built with thread support then +# BerkeleyDB was too. + +try: + import thread + del thread +except ImportError: + _db.DB_THREAD = 0 + + +#---------------------------------------------------------------------- |