mirror of
https://github.com/arsenetar/dupeguru.git
synced 2024-11-16 12:19:03 +00:00
334f4dd2ae
This makes md5 computing faster without using too much memory.
263 lines
8.7 KiB
Python
263 lines
8.7 KiB
Python
# Created By: Virgil Dupras
|
|
# Created On: 2009-10-22
|
|
# Copyright 2015 Hardcoded Software (http://www.hardcoded.net)
|
|
#
|
|
# This software is licensed under the "GPLv3" License as described in the "LICENSE" file,
|
|
# which should be included with this package. The terms are also available at
|
|
# http://www.gnu.org/licenses/gpl-3.0.html
|
|
|
|
# This is a fork from hsfs. The reason for this fork is that hsfs has been designed for musicGuru
|
|
# and was re-used for dupeGuru. The problem is that hsfs is way over-engineered for dupeGuru,
|
|
# resulting needless complexity and memory usage. It's been a while since I wanted to do that fork,
|
|
# and I'm doing it now.
|
|
|
|
import hashlib
|
|
import logging
|
|
|
|
from hscommon.util import nonone, get_file_ext
|
|
|
|
__all__ = [
|
|
'File',
|
|
'Folder',
|
|
'get_file',
|
|
'get_files',
|
|
'FSError',
|
|
'AlreadyExistsError',
|
|
'InvalidPath',
|
|
'InvalidDestinationError',
|
|
'OperationError',
|
|
]
|
|
|
|
NOT_SET = object()
|
|
|
|
class FSError(Exception):
|
|
cls_message = "An error has occured on '{name}' in '{parent}'"
|
|
|
|
def __init__(self, fsobject, parent=None):
|
|
message = self.cls_message
|
|
if isinstance(fsobject, str):
|
|
name = fsobject
|
|
elif isinstance(fsobject, File):
|
|
name = fsobject.name
|
|
else:
|
|
name = ''
|
|
parentname = str(parent) if parent is not None else ''
|
|
Exception.__init__(self, message.format(name=name, parent=parentname))
|
|
|
|
|
|
class AlreadyExistsError(FSError):
|
|
"The directory or file name we're trying to add already exists"
|
|
cls_message = "'{name}' already exists in '{parent}'"
|
|
|
|
class InvalidPath(FSError):
|
|
"The path of self is invalid, and cannot be worked with."
|
|
cls_message = "'{name}' is invalid."
|
|
|
|
class InvalidDestinationError(FSError):
|
|
"""A copy/move operation has been called, but the destination is invalid."""
|
|
cls_message = "'{name}' is an invalid destination for this operation."
|
|
|
|
class OperationError(FSError):
|
|
"""A copy/move/delete operation has been called, but the checkup after the
|
|
operation shows that it didn't work."""
|
|
cls_message = "Operation on '{name}' failed."
|
|
|
|
class File:
|
|
"""Represents a file and holds metadata to be used for scanning.
|
|
"""
|
|
INITIAL_INFO = {
|
|
'size': 0,
|
|
'mtime': 0,
|
|
'md5': '',
|
|
'md5partial': '',
|
|
}
|
|
# Slots for File make us save quite a bit of memory. In a memory test I've made with a lot of
|
|
# files, I saved 35% memory usage with "unread" files (no _read_info() call) and gains become
|
|
# even greater when we take into account read attributes (70%!). Yeah, it's worth it.
|
|
__slots__ = ('path', 'is_ref', 'words') + tuple(INITIAL_INFO.keys())
|
|
|
|
def __init__(self, path):
|
|
self.path = path
|
|
for attrname in self.INITIAL_INFO:
|
|
setattr(self, attrname, NOT_SET)
|
|
|
|
def __repr__(self):
|
|
return "<{} {}>".format(self.__class__.__name__, str(self.path))
|
|
|
|
def __getattribute__(self, attrname):
|
|
result = object.__getattribute__(self, attrname)
|
|
if result is NOT_SET:
|
|
try:
|
|
self._read_info(attrname)
|
|
except Exception as e:
|
|
logging.warning("An error '%s' was raised while decoding '%s'", e, repr(self.path))
|
|
result = object.__getattribute__(self, attrname)
|
|
if result is NOT_SET:
|
|
result = self.INITIAL_INFO[attrname]
|
|
return result
|
|
|
|
#This offset is where we should start reading the file to get a partial md5
|
|
#For audio file, it should be where audio data starts
|
|
def _get_md5partial_offset_and_size(self):
|
|
return (0x4000, 0x4000) #16Kb
|
|
|
|
def _read_info(self, field):
|
|
if field in ('size', 'mtime'):
|
|
stats = self.path.stat()
|
|
self.size = nonone(stats.st_size, 0)
|
|
self.mtime = nonone(stats.st_mtime, 0)
|
|
elif field == 'md5partial':
|
|
try:
|
|
fp = self.path.open('rb')
|
|
offset, size = self._get_md5partial_offset_and_size()
|
|
fp.seek(offset)
|
|
partialdata = fp.read(size)
|
|
md5 = hashlib.md5(partialdata)
|
|
self.md5partial = md5.digest()
|
|
fp.close()
|
|
except Exception:
|
|
pass
|
|
elif field == 'md5':
|
|
try:
|
|
fp = self.path.open('rb')
|
|
md5 = hashlib.md5()
|
|
# The goal here is to not run out of memory on really big files. However, the chunk
|
|
# size has to be large enough so that the python loop isn't too costly in terms of
|
|
# CPU.
|
|
CHUNK_SIZE = 1024 * 1024 # 1 mb
|
|
filedata = fp.read(CHUNK_SIZE)
|
|
while filedata:
|
|
md5.update(filedata)
|
|
filedata = fp.read(CHUNK_SIZE)
|
|
self.md5 = md5.digest()
|
|
fp.close()
|
|
except Exception:
|
|
pass
|
|
|
|
def _read_all_info(self, attrnames=None):
|
|
"""Cache all possible info.
|
|
|
|
If `attrnames` is not None, caches only attrnames.
|
|
"""
|
|
if attrnames is None:
|
|
attrnames = self.INITIAL_INFO.keys()
|
|
for attrname in attrnames:
|
|
getattr(self, attrname)
|
|
|
|
#--- Public
|
|
@classmethod
|
|
def can_handle(cls, path):
|
|
"""Returns whether this file wrapper class can handle ``path``.
|
|
"""
|
|
return not path.islink() and path.isfile()
|
|
|
|
def rename(self, newname):
|
|
if newname == self.name:
|
|
return
|
|
destpath = self.path.parent()[newname]
|
|
if destpath.exists():
|
|
raise AlreadyExistsError(newname, self.path.parent())
|
|
try:
|
|
self.path.rename(destpath)
|
|
except EnvironmentError:
|
|
raise OperationError(self)
|
|
if not destpath.exists():
|
|
raise OperationError(self)
|
|
self.path = destpath
|
|
|
|
def get_display_info(self, group, delta):
|
|
"""Returns a display-ready dict of dupe's data.
|
|
"""
|
|
raise NotImplementedError()
|
|
|
|
#--- Properties
|
|
@property
|
|
def extension(self):
|
|
return get_file_ext(self.name)
|
|
|
|
@property
|
|
def name(self):
|
|
return self.path.name
|
|
|
|
@property
|
|
def folder_path(self):
|
|
return self.path.parent()
|
|
|
|
|
|
class Folder(File):
|
|
"""A wrapper around a folder path.
|
|
|
|
It has the size/md5 info of a File, but it's value are the sum of its subitems.
|
|
"""
|
|
__slots__ = File.__slots__ + ('_subfolders', )
|
|
|
|
def __init__(self, path):
|
|
File.__init__(self, path)
|
|
self._subfolders = None
|
|
|
|
def _all_items(self):
|
|
folders = self.subfolders
|
|
files = get_files(self.path)
|
|
return folders + files
|
|
|
|
def _read_info(self, field):
|
|
if field in {'size', 'mtime'}:
|
|
size = sum((f.size for f in self._all_items()), 0)
|
|
self.size = size
|
|
stats = self.path.stat()
|
|
self.mtime = nonone(stats.st_mtime, 0)
|
|
elif field in {'md5', 'md5partial'}:
|
|
# What's sensitive here is that we must make sure that subfiles'
|
|
# md5 are always added up in the same order, but we also want a
|
|
# different md5 if a file gets moved in a different subdirectory.
|
|
def get_dir_md5_concat():
|
|
items = self._all_items()
|
|
items.sort(key=lambda f: f.path)
|
|
md5s = [getattr(f, field) for f in items]
|
|
return b''.join(md5s)
|
|
|
|
md5 = hashlib.md5(get_dir_md5_concat())
|
|
digest = md5.digest()
|
|
setattr(self, field, digest)
|
|
|
|
@property
|
|
def subfolders(self):
|
|
if self._subfolders is None:
|
|
subfolders = [p for p in self.path.listdir() if not p.islink() and p.isdir()]
|
|
self._subfolders = [self.__class__(p) for p in subfolders]
|
|
return self._subfolders
|
|
|
|
@classmethod
|
|
def can_handle(cls, path):
|
|
return not path.islink() and path.isdir()
|
|
|
|
|
|
def get_file(path, fileclasses=[File]):
|
|
"""Wraps ``path`` around its appropriate :class:`File` class.
|
|
|
|
Whether a class is "appropriate" is decided by :meth:`File.can_handle`
|
|
|
|
:param Path path: path to wrap
|
|
:param fileclasses: List of candidate :class:`File` classes
|
|
"""
|
|
for fileclass in fileclasses:
|
|
if fileclass.can_handle(path):
|
|
return fileclass(path)
|
|
|
|
def get_files(path, fileclasses=[File]):
|
|
"""Returns a list of :class:`File` for each file contained in ``path``.
|
|
|
|
:param Path path: path to scan
|
|
:param fileclasses: List of candidate :class:`File` classes
|
|
"""
|
|
assert all(issubclass(fileclass, File) for fileclass in fileclasses)
|
|
try:
|
|
result = []
|
|
for path in path.listdir():
|
|
file = get_file(path, fileclasses=fileclasses)
|
|
if file is not None:
|
|
result.append(file)
|
|
return result
|
|
except EnvironmentError:
|
|
raise InvalidPath(path)
|