sqlmap/lib/core/bigarray.py
2012-06-27 20:56:43 +02:00

109 lines
3.2 KiB
Python

#!/usr/bin/env python
"""
Copyright (c) 2006-2012 sqlmap developers (http://www.sqlmap.org/)
See the file 'doc/COPYING' for copying permission
"""
import os
import pickle
import tempfile
from lib.core.settings import BIGARRAY_CHUNK_LENGTH
class Cache:
"""
Auxiliary class used for storing cached chunks
"""
def __init__(self, index, data, dirty):
self.index = index
self.data = data
self.dirty = dirty
class BigArray(list):
"""
List-like class used for storing large amounts of data (disk cached)
"""
def __init__(self):
self.chunks = [[]]
self.cache = None
self.length = 0
self.filenames = set()
def append(self, value):
self.chunks[-1].append(value)
if len(self.chunks[-1]) >= BIGARRAY_CHUNK_LENGTH:
filename = self._dump(self.chunks[-1])
del(self.chunks[-1][:])
self.chunks[-1] = filename
self.chunks.append([])
def pop(self):
if len(self.chunks[-1]) < 1:
self.chunks.pop()
with open(self.chunks[-1], "rb") as fp:
self.chunks[-1] = pickle.load(fp)
return self.chunks[-1].pop()
def index(self, value):
for index in xrange(len(self)):
if self[index] == value:
return index
return ValueError, "%s is not in list" % value
def _dump(self, value):
handle, filename = tempfile.mkstemp()
self.filenames.add(filename)
os.close(handle)
with open(filename, "w+b") as fp:
pickle.dump(value, fp)
return filename
def _checkcache(self, index):
if (self.cache and self.cache.index != index and self.cache.dirty):
filename = self._dump(self.cache.data)
self.chunks[self.cache.index] = filename
if not (self.cache and self.cache.index == index):
with open(self.chunks[index], "rb") as fp:
self.cache = Cache(index, pickle.load(fp), False)
def __getitem__(self, y):
index = y / BIGARRAY_CHUNK_LENGTH
offset = y % BIGARRAY_CHUNK_LENGTH
chunk = self.chunks[index]
if isinstance(chunk, list):
return chunk[offset]
else:
self._checkcache(index)
return self.cache.data[offset]
def __setitem__(self, y, value):
index = y / BIGARRAY_CHUNK_LENGTH
offset = y % BIGARRAY_CHUNK_LENGTH
chunk = self.chunks[index]
if isinstance(chunk, list):
chunk[offset] = value
else:
self._checkcache(index)
self.cache.data[offset] = value
self.cache.dirty = True
def __repr__(self):
return "%s%s" % ("..." if len(self.chunks) > 1 else "", self.chunks[-1].__repr__())
def __iter__(self):
for i in xrange(len(self)):
yield self[i]
def __len__(self):
return len(self.chunks[-1]) if len(self.chunks) == 1 else (len(self.chunks) - 1) * BIGARRAY_CHUNK_LENGTH + len(self.chunks[-1])
def __del__(self):
for filename in self.filenames:
try:
os.remove(filename)
except OSError:
pass