mirror of
https://github.com/Mikaela/Limnoria.git
synced 2024-12-25 20:22:45 +01:00
472 lines
14 KiB
Python
472 lines
14 KiB
Python
###
|
|
# Copyright (c) 2002-2004, Jeremiah Fincher
|
|
# All rights reserved.
|
|
#
|
|
# Redistribution and use in source and binary forms, with or without
|
|
# modification, are permitted provided that the following conditions are met:
|
|
#
|
|
# * Redistributions of source code must retain the above copyright notice,
|
|
# this list of conditions, and the following disclaimer.
|
|
# * 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.
|
|
# * Neither the name of the author of this software nor the name of
|
|
# contributors to this software may be used to endorse or promote products
|
|
# derived from this software without specific prior written consent.
|
|
#
|
|
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 THE COPYRIGHT OWNER 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.
|
|
###
|
|
|
|
"""
|
|
Database module, similar to dbhash. Uses a format similar to (if not entirely
|
|
the same as) DJB's CDB <http://cr.yp.to/cdb.html>.
|
|
"""
|
|
|
|
__revision__ = "$Id$"
|
|
|
|
import supybot.fix as fix
|
|
|
|
import os
|
|
import sys
|
|
import sets
|
|
import struct
|
|
import os.path
|
|
import cPickle as pickle
|
|
|
|
import supybot.utils as utils
|
|
|
|
def hash(s):
|
|
"""DJB's hash function for CDB."""
|
|
h = 5381
|
|
for c in s:
|
|
h = ((h + (h << 5)) ^ ord(c)) & 0xFFFFFFFFL
|
|
return h
|
|
|
|
def unpack2Ints(s):
|
|
"""Returns two ints unpacked from the binary string s."""
|
|
return struct.unpack('<LL', s)
|
|
|
|
def pack2Ints(i, j):
|
|
"""Returns a packed binary string from the two ints."""
|
|
return struct.pack('<LL', i, j)
|
|
|
|
def dump(map, fd=sys.stdout):
|
|
"""Dumps a dictionary-structure in CDB format."""
|
|
for (key, value) in map.iteritems():
|
|
fd.write('+%s,%s:%s->%s\n' % (len(key), len(value), key, value))
|
|
|
|
def open(filename, mode='r'):
|
|
"""Opens a database; used for compatibility with other database modules."""
|
|
if mode == 'r':
|
|
return Reader(filename)
|
|
elif mode == 'w':
|
|
return ReaderWriter(filename)
|
|
elif mode == 'c':
|
|
if os.path.exists(filename):
|
|
return ReaderWriter(filename)
|
|
else:
|
|
maker = Maker(filename)
|
|
maker.finish()
|
|
return ReaderWriter(filename)
|
|
elif mode == 'n':
|
|
maker = Maker(filename)
|
|
maker.finish()
|
|
return ReaderWriter(filename)
|
|
else:
|
|
raise ValueError, 'Invalid flag: %s' % mode
|
|
|
|
def shelf(filename, *args, **kwargs):
|
|
"""Opens a new shelf database object."""
|
|
if os.path.exists(filename):
|
|
return Shelf(filename, *args, **kwargs)
|
|
else:
|
|
maker = Maker(filename)
|
|
maker.finish()
|
|
return Shelf(filename, *args, **kwargs)
|
|
|
|
def _readKeyValue(fd):
|
|
klen = 0
|
|
dlen = 0
|
|
s = initchar = fd.read(1)
|
|
if s == '':
|
|
return (None, None, None)
|
|
s = fd.read(1)
|
|
while s != ',':
|
|
klen = 10 * klen + int(s)
|
|
s = fd.read(1)
|
|
s = fd.read(1)
|
|
while s != ':':
|
|
dlen = 10 * dlen + int(s)
|
|
s = fd.read(1)
|
|
key = fd.read(klen)
|
|
assert fd.read(2) == '->'
|
|
value = fd.read(dlen)
|
|
assert fd.read(1) == '\n'
|
|
return (initchar, key, value)
|
|
|
|
def make(dbFilename, readFilename=None):
|
|
"""Makes a database from the filename, otherwise uses stdin."""
|
|
if readFilename is None:
|
|
readfd = sys.stdin
|
|
else:
|
|
readfd = file(readFilename, 'r')
|
|
maker = Maker(dbFilename)
|
|
while 1:
|
|
(initchar, key, value) = _readKeyValue(readfd)
|
|
if initchar is None:
|
|
break
|
|
assert initchar == '+'
|
|
maker.add(key, value)
|
|
readfd.close()
|
|
maker.finish()
|
|
|
|
|
|
class Maker(object):
|
|
"""Class for making CDB databases."""
|
|
def __init__(self, filename):
|
|
self.fd = utils.transactionalFile(filename)
|
|
self.filename = filename
|
|
self.fd.seek(2048)
|
|
self.hashPointers = [(0, 0)] * 256
|
|
#self.hashes = [[]] * 256 # Can't use this, [] stays the same...
|
|
self.hashes = []
|
|
for _ in xrange(256):
|
|
self.hashes.append([])
|
|
|
|
def add(self, key, data):
|
|
"""Adds a key->value pair to the database."""
|
|
h = hash(key)
|
|
hashPointer = h % 256
|
|
startPosition = self.fd.tell()
|
|
self.fd.write(pack2Ints(len(key), len(data)))
|
|
self.fd.write(key)
|
|
self.fd.write(data)
|
|
self.hashes[hashPointer].append((h, startPosition))
|
|
|
|
def finish(self):
|
|
"""Finishes the current Maker object.
|
|
|
|
Writes the remainder of the database to disk.
|
|
"""
|
|
for i in xrange(256):
|
|
hash = self.hashes[i]
|
|
self.hashPointers[i] = (self.fd.tell(), self._serializeHash(hash))
|
|
self._serializeHashPointers()
|
|
self.fd.flush()
|
|
self.fd.close()
|
|
|
|
def _serializeHash(self, hash):
|
|
hashLen = len(hash) * 2
|
|
a = [(0, 0)] * hashLen
|
|
for (h, pos) in hash:
|
|
i = (h / 256) % hashLen
|
|
while a[i] != (0, 0):
|
|
i = (i + 1) % hashLen
|
|
a[i] = (h, pos)
|
|
for (h, pos) in a:
|
|
self.fd.write(pack2Ints(h, pos))
|
|
return hashLen
|
|
|
|
def _serializeHashPointers(self):
|
|
self.fd.seek(0)
|
|
for (hashPos, hashLen) in self.hashPointers:
|
|
self.fd.write(pack2Ints(hashPos, hashLen))
|
|
|
|
|
|
class Reader(utils.IterableMap):
|
|
"""Class for reading from a CDB database."""
|
|
def __init__(self, filename):
|
|
self.filename = filename
|
|
self.fd = file(filename, 'r')
|
|
self.loop = 0
|
|
self.khash = 0
|
|
self.kpos = 0
|
|
self.hpos = 0
|
|
self.hslots = 0
|
|
self.dpos = 0
|
|
self.dlen = 0
|
|
|
|
def close(self):
|
|
self.fd.close()
|
|
|
|
def _read(self, len, pos):
|
|
self.fd.seek(pos)
|
|
return self.fd.read(len)
|
|
|
|
def _match(self, key, pos):
|
|
return self._read(len(key), pos) == key
|
|
|
|
def iteritems(self):
|
|
# uses loop/hslots in a strange, non-re-entrant manner.
|
|
(self.loop,) = struct.unpack('<i', self._read(4, 0))
|
|
self.hslots = 2048
|
|
while self.hslots < self.loop:
|
|
(klen, dlen) = unpack2Ints(self._read(8, self.hslots))
|
|
dpos = self.hslots + 8 + klen
|
|
ret = (self._read(klen, self.hslots+8), self._read(dlen, dpos))
|
|
self.hslots = dpos + dlen
|
|
yield ret
|
|
self.loop = 0
|
|
self.hslots = 0
|
|
|
|
def _findnext(self, key):
|
|
if not self.loop:
|
|
self.khash = hash(key)
|
|
(self.hpos, self.hslots) = unpack2Ints(self._read(8,
|
|
(self.khash * 8) & 2047))
|
|
if not self.hslots:
|
|
return False
|
|
self.kpos = self.hpos + (((self.khash / 256) % self.hslots) * 8)
|
|
while self.loop < self.hslots:
|
|
(h, p) = unpack2Ints(self._read(8, self.kpos))
|
|
if p == 0:
|
|
return False
|
|
self.loop += 1
|
|
self.kpos += 8
|
|
if self.kpos == self.hpos + (self.hslots * 8):
|
|
self.kpos = self.hpos
|
|
if h == self.khash:
|
|
(u, self.dlen) = unpack2Ints(self._read(8, p))
|
|
if u == len(key):
|
|
if self._match(key, p+8):
|
|
self.dpos = p + 8 + u
|
|
return True
|
|
return False
|
|
|
|
def _find(self, key, loop=0):
|
|
self.loop = loop
|
|
return self._findnext(key)
|
|
|
|
def _getCurrentData(self):
|
|
return self._read(self.dlen, self.dpos)
|
|
|
|
def find(self, key, loop=0):
|
|
if self._find(key, loop=loop):
|
|
return self._getCurrentData()
|
|
else:
|
|
try:
|
|
return self.default
|
|
except AttributeError:
|
|
raise KeyError, key
|
|
|
|
def findall(self, key):
|
|
ret = []
|
|
while self._findnext(key):
|
|
ret.append(self._getCurrentData())
|
|
return ret
|
|
|
|
def get(self, key, default=None):
|
|
try:
|
|
return self[key]
|
|
except KeyError:
|
|
return default
|
|
|
|
def __len__(self):
|
|
(start,) = struct.unpack('<i', self._read(4, 0))
|
|
self.fd.seek(0, 2)
|
|
return ((self.fd.tell() - start) / 16)
|
|
|
|
has_key = _find
|
|
__contains__ = has_key
|
|
__getitem__ = find
|
|
|
|
|
|
class ReaderWriter(utils.IterableMap):
|
|
"""Uses a journal to pretend that a CDB is writable database."""
|
|
def __init__(self, filename, journalName=None, maxmods=0):
|
|
if journalName is None:
|
|
journalName = filename + '.journal'
|
|
self.journalName = journalName
|
|
self.maxmods = maxmods
|
|
self.mods = 0
|
|
self.filename = filename
|
|
self._readJournal()
|
|
self._openFiles()
|
|
self.adds = {}
|
|
self.removals = sets.Set()
|
|
|
|
def _openFiles(self):
|
|
self.cdb = Reader(self.filename)
|
|
self.journal = file(self.journalName, 'w')
|
|
|
|
def _closeFiles(self):
|
|
self.cdb.close()
|
|
self.journal.close()
|
|
|
|
def _journalRemoveKey(self, key):
|
|
s = '-%s,%s:%s->%s\n' % (len(key), 0, key, '')
|
|
self.journal.write(s)
|
|
self.journal.flush()
|
|
|
|
def _journalAddKey(self, key, value):
|
|
s = '+%s,%s:%s->%s\n' % (len(key), len(value), key, value)
|
|
self.journal.write(s)
|
|
self.journal.flush()
|
|
|
|
def _readJournal(self):
|
|
removals = sets.Set()
|
|
adds = {}
|
|
try:
|
|
fd = file(self.journalName, 'r')
|
|
while 1:
|
|
(initchar, key, value) = _readKeyValue(fd)
|
|
if initchar is None:
|
|
break
|
|
elif initchar == '+':
|
|
if key in removals:
|
|
removals.remove(key)
|
|
adds[key] = value
|
|
elif initchar == '-':
|
|
if key in adds:
|
|
del adds[key]
|
|
removals.add(key)
|
|
fd.close()
|
|
except IOError:
|
|
pass
|
|
if removals or adds:
|
|
tempfilename = utils.mktemp('.db')
|
|
maker = Maker(tempfilename)
|
|
cdb = Reader(self.filename)
|
|
for (key, value) in cdb.iteritems():
|
|
if key in removals:
|
|
continue
|
|
elif key in adds:
|
|
value = adds[key]
|
|
if value is not None:
|
|
maker.add(key, value)
|
|
adds[key] = None
|
|
else:
|
|
maker.add(key, value)
|
|
for (key, value) in adds.iteritems():
|
|
if value is not None:
|
|
maker.add(key, value)
|
|
cdb.close()
|
|
maker.finish()
|
|
os.rename(tempfilename, self.filename)
|
|
if os.path.exists(self.journalName):
|
|
os.remove(self.journalName)
|
|
|
|
def close(self):
|
|
self.flush()
|
|
self._closeFiles()
|
|
|
|
def flush(self):
|
|
self._closeFiles()
|
|
self._readJournal()
|
|
self._openFiles()
|
|
|
|
def _flushIfOverLimit(self):
|
|
if self.maxmods:
|
|
if self.mods > self.maxmods:
|
|
self.flush()
|
|
self.mods = 0
|
|
|
|
def __getitem__(self, key):
|
|
if key in self.removals:
|
|
raise KeyError, key
|
|
else:
|
|
try:
|
|
return self.adds[key]
|
|
except KeyError:
|
|
return self.cdb[key] # If this raises KeyError, we lack key.
|
|
|
|
def __delitem__(self, key):
|
|
if key in self.removals:
|
|
raise KeyError, key
|
|
else:
|
|
if key in self.adds and key in self.cdb:
|
|
self._journalRemoveKey(key)
|
|
del self.adds[key]
|
|
self.removals.add(key)
|
|
elif key in self.adds:
|
|
self._journalRemoveKey(key)
|
|
del self.adds[key]
|
|
elif key in self.cdb:
|
|
self._journalRemoveKey(key)
|
|
else:
|
|
raise KeyError, key
|
|
self.mods += 1
|
|
self._flushIfOverLimit()
|
|
|
|
def __setitem__(self, key, value):
|
|
if key in self.removals:
|
|
self.removals.remove(key)
|
|
self._journalAddKey(key, value)
|
|
self.adds[key] = value
|
|
self.mods += 1
|
|
self._flushIfOverLimit()
|
|
|
|
def __contains__(self, key):
|
|
if key in self.removals:
|
|
return False
|
|
else:
|
|
return key in self.adds or key in self.cdb
|
|
|
|
has_key = __contains__
|
|
|
|
def iteritems(self):
|
|
already = sets.Set()
|
|
for (key, value) in self.cdb.iteritems():
|
|
if key in self.removals or key in already:
|
|
continue
|
|
elif key in self.adds:
|
|
already.add(key)
|
|
yield (key, self.adds[key])
|
|
else:
|
|
yield (key, value)
|
|
for (key, value) in self.adds.iteritems():
|
|
if key not in already:
|
|
yield (key, value)
|
|
|
|
def setdefault(self, key, value):
|
|
try:
|
|
return self[key]
|
|
except KeyError:
|
|
self[key] = value
|
|
return value
|
|
|
|
def get(self, key, default=None):
|
|
try:
|
|
return self[key]
|
|
except KeyError:
|
|
return default
|
|
|
|
|
|
class Shelf(ReaderWriter):
|
|
"""Uses pickle to mimic the shelf module."""
|
|
def __getitem__(self, key):
|
|
return pickle.loads(ReaderWriter.__getitem__(self, key))
|
|
|
|
def __setitem__(self, key, value):
|
|
ReaderWriter.__setitem__(self, key, pickle.dumps(value, True))
|
|
|
|
def iteritems(self):
|
|
for (key, value) in ReaderWriter.iteritems(self):
|
|
yield (key, pickle.loads(value))
|
|
|
|
|
|
if __name__ == '__main__':
|
|
if sys.argv[0] == 'cdbdump':
|
|
if len(sys.argv) == 2:
|
|
fd = file(sys.argv[1], 'r')
|
|
else:
|
|
fd = sys.stdin
|
|
db = Reader(fd)
|
|
dump(db)
|
|
elif sys.argv[0] == 'cdbmake':
|
|
if len(sys.argv) == 2:
|
|
make(sys.argv[1])
|
|
else:
|
|
make(sys.argv[1], sys.argv[2])
|
|
# vim:set shiftwidth=4 tabstop=8 expandtab textwidth=78:
|