Various improvements in coding style.

12 files changed, 192 insertions, 253 deletions

diff --git a/minidinstall/ChangeFile.py b/minidinstall/ChangeFile.py
index 3b0cf48..4a65af6 100644
--- a/minidinstall/ChangeFile.py
+++ b/minidinstall/ChangeFile.py
@@ -1,8 +1,8 @@
-# ChangeFile
+# ChangeFile -*- mode: python; coding: utf-8 -*-
 
 # A class which represents a Debian change file.
 
-# Copyright 2002 Colin Walters <walters@gnu.org>
+# Copyright (c) 2002 Colin Walters <walters@gnu.org>
 
 # This file is free software; you can redistribute it and/or modify it
 # under the terms of the GNU General Public License as published by
@@ -18,11 +18,11 @@
 # along with this program; if not, write to the Free Software
 # Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
-import os, re, sys, string, stat
-import threading, queue
+import os, re, stat
 import logging
-from minidinstall import DpkgControl, SignedFile
-from minidinstall import misc
+from .DpkgControl import *
+from .SignedFile import *
+from . import misc
 
 class ChangeFileException(Exception):
     def __init__(self, value):
@@ -30,19 +30,19 @@ class ChangeFileException(Exception):
     def __str__(self):
         return repr(self._value)
 
-class ChangeFile(DpkgControl.DpkgParagraph):
-    md5_re = r'^(?P<md5>[0-9a-f]{32})[ \t]+(?P<size>\d+)[ \t]+(?P<section>[-/a-zA-Z0-9]+)[ \t]+(?P<priority>[-a-zA-Z0-9]+)[ \t]+(?P<file>[0-9a-zA-Z][-+:.,=~0-9a-zA-Z_]+)$'
-    sha1_re = r'^(?P<sha1>[0-9a-f]{40})[ \t]+(?P<size>\d+)[ \t]+(?P<file>[0-9a-zA-Z][-+:.,=~0-9a-zA-Z_]+)$'
-    sha256_re = r'^(?P<sha256>[0-9a-f]{64})[ \t]+(?P<size>\d+)[ \t]+(?P<file>[0-9a-zA-Z][-+:.,=~0-9a-zA-Z_]+)$'
+class ChangeFile(DpkgParagraph):
+    md5_re = r'^(?P<hashsum>[0-9a-f]{32})[ \t]+(?P<size>\d+)[ \t]+(?P<section>[-/a-zA-Z0-9]+)[ \t]+(?P<priority>[-a-zA-Z0-9]+)[ \t]+(?P<file>[0-9a-zA-Z][-+:.,=~0-9a-zA-Z_]+)$'
+    sha1_re = r'^(?P<hashsum>[0-9a-f]{40})[ \t]+(?P<size>\d+)[ \t]+(?P<file>[0-9a-zA-Z][-+:.,=~0-9a-zA-Z_]+)$'
+    sha256_re = r'^(?P<hashsum>[0-9a-f]{64})[ \t]+(?P<size>\d+)[ \t]+(?P<file>[0-9a-zA-Z][-+:.,=~0-9a-zA-Z_]+)$'
 
     def __init__(self):
-        DpkgControl.DpkgParagraph.__init__(self)
+        DpkgParagraph.__init__(self)
         self._logger = logging.getLogger("mini-dinstall")
         self._file = ''
 
     def load_from_file(self, filename):
         self._file = filename
-        f = SignedFile.SignedFile(open(self._file))
+        f = SignedFile(open(self._file))
         self.load(f)
         f.close()
 
@@ -52,57 +52,50 @@ class ChangeFile(DpkgControl.DpkgParagraph):
     def _get_checksum_from_changes(self):
         """ extract checksums and size from changes file """
         output = {}
-        hashes = { 'md5': ['files', re.compile(self.md5_re)],
-                   'sha1': ['checksums-sha1', re.compile(self.sha1_re)],
-                   'sha256': ['checksums-sha256', re.compile(self.sha256_re)]
-                 }
-        hashes_checked = hashes.copy()
+        hashes = {
+            'md5': ['files', re.compile(self.md5_re)],
+            'sha1': ['checksums-sha1', re.compile(self.sha1_re)],
+            'sha256': ['checksums-sha256', re.compile(self.sha256_re)]
+        }
 
-        try:
-            self['files']
-        except KeyError:
+        if 'files' not in self:
             return []
 
-        for hash in hashes:
-            try:
-                self[hashes[hash][0]]
-            except KeyError:
+        for (hash, (field, regex)) in list(hashes.items()):
+            if field not in self:
                 self._logger.warn("Can't find %s checksum in changes file '%s'" % (hash, os.path.basename(self._file)))
-                hashes_checked.pop(hash)
-
-        for hash in hashes_checked:
+                continue
             output[hash] = []
-            for line in self[hashes[hash][0]]:
-                if line == '':
+            for line in self[field].splitlines():
+                if not line:
                     continue
-                match = hashes[hash][1].match(line)
-                if (match is None):
-                    raise ChangeFileException("Couldn't parse file entry \"%s\" in Files field of .changes" % (line,))
-                output[hash].append([match.group(hash), match.group('size'), match.group('file') ])
+                match = regex.match(line)
+                if not match:
+                    raise ChangeFileException("Couldn't parse file entry \"%s\" in %s field of .changes" % (line, self.trueFieldCasing[field]))
+                output[hash].append([match.group('hashsum'), match.group('size'), match.group('file')])
         return output
 
     def verify(self, sourcedir):
         """ verify size and hash values from changes file """
         checksum = self._get_checksum_from_changes()
-        for hash in list(checksum.keys()):
-            for (hashsum, size, filename) in checksum[hash]:
+        for (hash, value) in list(checksum.items()):
+            for (hashsum, size, filename) in value:
                 self._verify_file_integrity(os.path.join(sourcedir, filename), int(size), hash, hashsum)
 
-
     def _verify_file_integrity(self, filename, expected_size, hash, expected_hashsum):
         """ check uploaded file integrity """
-        self._logger.debug('Checking integrity of %s' % (filename,))
+        self._logger.debug('Checking integrity of %s' % filename)
         try:
             statbuf = os.stat(filename)
             if not stat.S_ISREG(statbuf[stat.ST_MODE]):
-                raise ChangeFileException("%s is not a regular file" % (filename,))
+                raise ChangeFileException("%s is not a regular file" % filename)
             size = statbuf[stat.ST_SIZE]
         except OSError as e:
-            raise ChangeFileException("Can't stat %s: %s" % (filename,e.strerror))
+            raise ChangeFileException("Can't stat %s: %s" % (filename, e.strerror))
         if size != expected_size:
-            raise ChangeFileException("File size for %s does not match that specified in .dsc" % (filename,))
-        if (misc.get_file_sum(self, hash, filename) != expected_hashsum):
-            raise ChangeFileException("%ssum for %s does not match that specified in .dsc" % (hash, filename,))
+            raise ChangeFileException("File size for %s does not match that specified in .dsc" % filename)
+        if misc.get_file_sum(self, hash, filename) != expected_hashsum:
+            raise ChangeFileException("%ssum for %s does not match that specified in .dsc" % (hash, filename))
         self._logger.debug('Verified %ssum %s and size %s for %s' % (hash, expected_hashsum, expected_size, filename))
 
 # vim:ts=4:sw=4:et:
diff --git a/minidinstall/DebianSigVerifier.py b/minidinstall/DebianSigVerifier.py
index d441a58..17a6ec2 100644
--- a/minidinstall/DebianSigVerifier.py
+++ b/minidinstall/DebianSigVerifier.py
@@ -2,7 +2,7 @@
 
 # A class for verifying signed files, using Debian keys
 
-# Copyright © 2002 Colin Walters <walters@gnu.org>
+# Copyright (c) 2002 Colin Walters <walters@gnu.org>
 
 # This file is free software; you can redistribute it and/or modify it
 # under the terms of the GNU General Public License as published by
@@ -18,18 +18,19 @@
 # along with this program; if not, write to the Free Software
 # Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
-import os, re, sys, string, stat, logging
-from minidinstall.GPGSigVerifier import GPGSigVerifier
+import os
+from .GPGSigVerifier import *
 
 class DebianSigVerifier(GPGSigVerifier):
     _dpkg_ring = '/etc/dpkg/local-keyring.gpg'
+
     def __init__(self, keyrings=None, extra_keyrings=None):
-        if keyrings is None:
+        if not keyrings:
             keyrings = ['/usr/share/keyrings/debian-keyring.gpg', '/usr/share/keyrings/debian-keyring.pgp']
         if os.access(self._dpkg_ring, os.R_OK):
             keyrings.append(self._dpkg_ring)
-        if not extra_keyrings is None:
-            keyrings += extra_keyrings
+        if extra_keyrings:
+            keyrings.extend(extra_keyrings)
         GPGSigVerifier.__init__(self, keyrings)
 
 # vim:ts=4:sw=4:et:
diff --git a/minidinstall/Dnotify.py b/minidinstall/Dnotify.py
index 18606e1..cdc2c48 100644
--- a/minidinstall/Dnotify.py
+++ b/minidinstall/Dnotify.py
@@ -2,7 +2,7 @@
 
 # A simple FAM-like beast in Python
 
-# Copyright © 2002 Colin Walters <walters@gnu.org>
+# Copyright (c) 2002 Colin Walters <walters@gnu.org>
 
 # This file is free software; you can redistribute it and/or modify it
 # under the terms of the GNU General Public License as published by
@@ -18,9 +18,9 @@
 # along with this program; if not, write to the Free Software
 # Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
-import os, re, sys, string, stat, threading, queue, time
+import os, stat, threading, queue, time
 import logging
-from minidinstall import misc
+from . import misc
 
 class DnotifyException(Exception):
     def __init__(self, value):
@@ -29,7 +29,7 @@ class DnotifyException(Exception):
         return repr(self._value)
 
 class DirectoryNotifierFactory:
-    def create(self, dirs, use_dnotify=1, poll_time=30, logger=None, cancel_event=None):
+    def create(self, dirs, use_dnotify=False, poll_time=30, logger=None, cancel_event=None):
         if use_dnotify and os.access('/usr/bin/dnotify', os.X_OK):
             if logger:
                 logger.debug("Using dnotify directory notifier")
@@ -47,11 +47,11 @@ class DirectoryNotifier:
     def __init__(self, dirs, logger, cancel_event=None):
         self._cwd = os.getcwd()
         self._dirs = dirs
-        if cancel_event is None:
+        if not cancel_event:
             self._cancel_event = threading.Event()
         else:
             self._cancel_event = cancel_event
-        if logger is None:
+        if not logger:
             self._logger = logging.getLogger("Dnotify")
             self._logger.addFilter(DnotifyNullLoggingFilter())
         else:
@@ -62,13 +62,13 @@ class DirectoryNotifier:
 
 class DirectoryNotifierAsyncWrapper(threading.Thread):
     def __init__(self, dnotify, queue, logger=None, name=None):
-        if not name is None:
+        if name:
             threading.Thread.__init__(self, name=name)
         else:
             threading.Thread.__init__(self)
         self._eventqueue = queue
         self._dnotify = dnotify
-        if logger is None:
+        if not logger:
             self._logger = logging.getLogger("Dnotify")
             self._logger.addFilter(DnotifyNullLoggingFilter())
         else:
@@ -78,7 +78,7 @@ class DirectoryNotifierAsyncWrapper(threading.Thread):
         self._cancel_event.set()
 
     def run(self):
-        self._logger.info('Created new thread (%s) for async directory notification' % (self.getName()))
+        self._logger.info('Created new thread (%s) for async directory notification' % self.getName())
         while not self._dnotify.cancelled():
             dir = self._dnotify.poll()
             self._eventqueue.put(dir)
@@ -97,7 +97,7 @@ class MtimeDirectoryNotifier(DirectoryNotifier):
         timeout_time = None
         if timeout:
             timeout_time = time.time() + timeout
-        while self._changed == []:
+        while not self._changed:
             if timeout_time and time.time() > timeout_time:
                 return None
             self._logger.debug('Polling...')
@@ -105,16 +105,15 @@ class MtimeDirectoryNotifier(DirectoryNotifier):
                 oldtime = self._dirmap[dir]
                 mtime = os.stat(os.path.join(self._cwd, dir))[stat.ST_MTIME]
                 if oldtime < mtime:
-                    self._logger.debug('Directory "%s" has changed' % (dir,))
+                    self._logger.debug('Directory "%s" has changed' % dir)
                     self._changed.append(dir)
                 self._dirmap[dir] = mtime
-            if self._changed == []:
+            if not self._changed:
                 for x in range(self._polltime):
                     if self._cancel_event.isSet():
                         return None
                     time.sleep(1)
-        ret = self._changed[0]
-        self._changed = self._changed[1:]
+        ret = self._changed.pop(0)
         return ret
 
 class DnotifyDirectoryNotifier(DirectoryNotifier):
@@ -127,11 +126,11 @@ class DnotifyDirectoryNotifier(DirectoryNotifier):
     def poll(self, timeout=None):
         # delete duplicates
         i = self._queue.qsize()
-        self._logger.debug('Queue size: %d', (i,))
+        self._logger.debug('Queue size: %d' % i)
         set = {}
-        while i > 0:
+        while i:
             dir = self._queue_get(timeout)
-            if dir is None:
+            if not dir:
                 # We shouldn't have to do this; no one else is reading
                 # from the queue.  But we do it just to be safe.
                 for key in list(set.keys()):
@@ -142,11 +141,11 @@ class DnotifyDirectoryNotifier(DirectoryNotifier):
         for key in list(set.keys()):
             self._queue.put(key)
         i = self._queue.qsize()
-        self._logger.debug('Queue size (after duplicate filter): %d', (i,))
+        self._logger.debug('Queue size (after duplicate filter): %d' % i)
         return self._queue_get(timeout)
 
     def _queue_get(self, timeout):
-        if timeout is None:
+        if not timeout:
             return self._queue.get()
         timeout_time = time.time() + timeout
         while True:
@@ -179,21 +178,21 @@ class DnotifyThread(threading.Thread):
         os.close(outfd)
         stdout = os.fdopen(infd)
         c = 'x'
-        while c != '':
+        while c:
             curline = ''
             c = stdout.read(1)
-            while c != '' and c != '\0':
+            while c and c != '\0':
                 curline += c
                 c = stdout.read(1)
-            if c == '':
+            if not c:
                 break
-            self._logger.debug('Directory "%s" changed' % (curline,))
+            self._logger.debug('Directory "%s" changed' % curline)
             self._queue.put(curline)
         (pid, status) = os.waitpid(pid, 0)
-        if status is None:
+        if not status:
             ecode = 0
         else:
             ecode = os.WEXITSTATUS(status)
-        raise DnotifyException("dnotify exited with code %s" % (ecode,))
+        raise DnotifyException("dnotify exited with code %s" % ecode)
 
 # vim:ts=4:sw=4:et:
diff --git a/minidinstall/DpkgControl.py b/minidinstall/DpkgControl.py
index be08155..02e3567 100755
--- a/minidinstall/DpkgControl.py
+++ b/minidinstall/DpkgControl.py
@@ -1,7 +1,10 @@
-# DpkgControl.py
+#!/usr/bin/python3
+# DpkgControl -*- mode: python; coding: utf-8 -*-
 #
 # This module implements control file parsing.
 #
+# Copyright (c) 2001 Adam Heath <doogie@debian.org>
+#
 # DpkgParagraph is a low-level class, that reads/parses a single paragraph
 # from a file object.
 #
@@ -16,9 +19,7 @@
 # To test this, pass it a filetype char, a filename, then, optionally,
 # the key to a paragraph to display, and if a fourth arg is given, only
 # show that field.
-#
-# Copyright 2001 Adam Heath <doogie@debian.org>
-#
+
 # This file is free software; you can redistribute it and/or modify it
 # under the terms of the GNU General Public License as published by
 # the Free Software Foundation; either version 2 of the License, or
@@ -33,20 +34,15 @@
 # along with this program; if not, write to the Free Software
 # Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
-import re, string
 from .DpkgDatalist import *
-from minidinstall.SignedFile import *
+from .SignedFile import *
 
 class DpkgParagraph(DpkgOrderedDatalist):
-    caseSensitive = 0
     trueFieldCasing = {}
 
-    def setCaseSensitive( self, value ):    self.caseSensitive = value
-
     def load( self, f ):
-        "Paragraph data from a file object."
+        """Paragraph data from a file object"""
         key = None
-        value = None
         while True:
             line = f.readline()
             if not line:
@@ -57,85 +53,53 @@ class DpkgParagraph(DpkgOrderedDatalist):
                     continue
                 else:
                     return
-            line = line[ :-1 ]
             if line[ 0 ] != ' ':
-                key, value = line.split( ":", 1 )
-                if value: value = value[ 1: ]
-                if not self.caseSensitive:
-                    newkey = key.lower()
-                    if key not in self.trueFieldCasing:
-                        self.trueFieldCasing[ newkey ] = key
-                    key = newkey
+                ( truekey, value ) = line.split( ":", 1 )
+                key = truekey.lower()
+                self.trueFieldCasing[ key ] = truekey
+                self[ key ] = value.strip()
             else:
-                if isinstance( value, list ):
-                    value.append( line[ 1: ] )
-                else:
-                    value = [ value, line[ 1: ] ]
-            self[ key ] = value
+                self[ key ] += "\n%s" % line.strip()
 
     def _storeField( self, f, value, lead = " " ):
-        if isinstance( value, list ):
-            value = "\n".join(list(map( lambda v, lead = lead: v and ( lead + v ) or v, value )))
-        else:
-            if value: value = lead + value
-        f.write( "%s\n" % ( value ) )
+        value = "\n".join(list(map( lambda v, lead = lead: lead + v if v else "", value.splitlines() )))
+        f.write( "%s\n" % value )
 
     def _store( self, f ):
-        "Write our paragraph data to a file object"
-        for key in list(self.keys()):
-            value = self[ key ]
-            if key in self.trueFieldCasing:
-                key = self.trueFieldCasing[ key ]
-            f.write( "%s:" % key )
+        """Write our paragraph data to a file object"""
+        for ( key, value ) in list(self.items()):
+            truekey = self.trueFieldCasing[ key ]
+            f.write( "%s:" % truekey )
             self._storeField( f, value )
 
-class DpkgControl(DpkgOrderedDatalist):
-
-    key = "package"
-    caseSensitive = 0
-
-    def setkey( self, key ):        self.key = key
-    def setCaseSensitive( self, value ):    self.caseSensitive = value
-
-    def _load_one( self, f ):
-        p = DpkgParagraph( None )
-        p.setCaseSensitive( self.caseSensitive )
-        p.load( f )
-        return p
-
-    def load( self, f ):
+class DpkgControl(DpkgParagraph):
+    def load( self, f, source = False ):
         while True:
-            p = self._load_one( f )
-            if not p: break
-            self[ p[ self.key ] ] = p
+            para = DpkgParagraph()
+            para.load( f )
+            if not para:
+                break
+            if "source" not in para:
+                self[ para[ "package" ] ] = para
+            elif source:
+                self[ "source" ] = para
 
     def _store( self, f ):
-        "Write our control data to a file object"
-
-        for key in list(self.keys()):
-            self[ key ]._store( f )
-            f.write( "\n" )
-
-class DpkgSourceControl( DpkgControl ):
-    source = None
-
+        """Write our control data to a file object"""
+        keys = list(self.keys())
+        while keys:
+            self[ keys.pop( 0 ) ]._store( f )
+            if keys:
+                f.write( "\n" )
+
+class DpkgSourceControl(DpkgControl):
     def load( self, f ):
-        f = SignedFile(f)
-        self.source = self._load_one( f )
-        DpkgControl.load( self, f )
-
-    def __repr__( self ):
-        return self.source.__repr__() + "\n" + DpkgControl.__repr__( self )
-
-    def _store( self, f ):
-        "Write our control data to a file object"
-        self.source._store( f )
-        f.write( "\n" )
-        DpkgControl._store( self, f )
+        f = SignedFile( f )
+        DpkgControl.load( self, f, source = True )
 
 if __name__ == "__main__":
     import sys
-    types = { 'p' : DpkgParagraph, 'c' : DpkgControl, 's' : DpkgSourceControl }
+    types = { 'p': DpkgParagraph, 'c': DpkgControl, 's': DpkgSourceControl }
     type = sys.argv[ 1 ]
     if type not in types:
         print( "Unknown type `%s'!" % type )
@@ -144,11 +108,13 @@ if __name__ == "__main__":
     data = types[ type ]()
     data.load( file )
     if len( sys.argv ) > 3:
-        para = data[ sys.argv[ 3 ] ]
-        if len( sys.argv ) > 4:
-            para._storeField( sys.stdout, para[ sys.argv[ 4 ] ], "" )
+        rargs = sys.argv[ 3: ]
+        if type != 'p':
+            data = data[ rargs.pop( 0 ) ]
+        if rargs:
+            data._storeField( sys.stdout, data[ rargs[ 0 ].lower() ], "" )
         else:
-            para._store( sys.stdout )
+            data._store( sys.stdout )
     else:
         data._store( sys.stdout )
 
diff --git a/minidinstall/DpkgDatalist.py b/minidinstall/DpkgDatalist.py
index 68f9940..e7abbd2 100644
--- a/minidinstall/DpkgDatalist.py
+++ b/minidinstall/DpkgDatalist.py
@@ -1,10 +1,10 @@
-# DpkgDatalist.py
+# DpkgDatalist -*- mode: python; coding: utf-8 -*-
 #
 # This module implements DpkgDatalist, an abstract class for storing 
 # a list of objects in a file. Children of this class have to implement
 # the load and _store methods.
 #
-# Copyright 2001 Wichert Akkerman <wichert@linux.com>
+# Copyright (c) 2001 Wichert Akkerman <wichert@linux.com>
 #
 # This file is free software; you can redistribute it and/or modify it
 # under the terms of the GNU General Public License as published by
@@ -20,34 +20,31 @@
 # along with this program; if not, write to the Free Software
 # Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
-import os, sys
-from collections import UserDict
-from collections import OrderedDict
-from minidinstall.SafeWriteFile import SafeWriteFile
+import sys
+from collections import UserDict, OrderedDict
+from .SafeWriteFile import SafeWriteFile
 
 class DpkgDatalistException(Exception):
     UNKNOWN     = 0
     SYNTAXERROR = 1
 
-    def __init__(self, message="", reason=UNKNOWN, file=None, line=None):
+    def __init__(self, message=None, reason=UNKNOWN, file=None, line=None):
         self.message=message
         self.reason=reason
         self.filename=file
         self.line=line
 
 class _DpkgDatalist:
-    def __init__(self, fn=""):
-        '''Initialize a DpkgDatalist object. An optional argument is a
-        file from which we load values.'''
-
+    def __init__(self, fn=None):
+        """Initialize a DpkgDatalist object. An optional argument is a
+        file from which we load values."""
         self.filename=fn
         if self.filename:
             self.load(self.filename)
 
     def store(self, fn=None):
-        "Store variable data in a file."
-
-        if fn==None:
+        """Store variable data in a file."""
+        if not fn:
             fn=self.filename
         # Special case for writing to stdout
         if not fn:
@@ -64,15 +61,13 @@ class _DpkgDatalist:
             if isinstance(fn, str):
                 vf.close()
 
-
 class DpkgDatalist(UserDict, _DpkgDatalist):
-    def __init__(self, fn=""):
+    def __init__(self, fn=None):
         UserDict.__init__(self)
         _DpkgDatalist.__init__(self, fn)
 
-
 class DpkgOrderedDatalist(OrderedDict, _DpkgDatalist):
-    def __init__(self, fn=""):
+    def __init__(self, fn=None):
         OrderedDict.__init__(self)
         _DpkgDatalist.__init__(self, fn)
 
diff --git a/minidinstall/GPGSigVerifier.py b/minidinstall/GPGSigVerifier.py
index 2e0dee5..0d47379 100644
--- a/minidinstall/GPGSigVerifier.py
+++ b/minidinstall/GPGSigVerifier.py
@@ -2,7 +2,7 @@
 
 # A class for verifying signed files
 
-# Copyright © 2002 Colin Walters <walters@gnu.org>
+# Copyright (c) 2002 Colin Walters <walters@gnu.org>
 
 # This file is free software; you can redistribute it and/or modify it
 # under the terms of the GNU General Public License as published by
@@ -18,8 +18,8 @@
 # along with this program; if not, write to the Free Software
 # Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
-import os, re, sys, string, stat
-from minidinstall import misc
+import os
+from . import misc
 
 class GPGSigVerifierException(Exception):
     def __init__(self, value):
@@ -40,10 +40,10 @@ class GPGSigVerificationFailure(Exception):
 class GPGSigVerifier:
     def __init__(self, keyrings, gpgv=None):
         self._keyrings = keyrings
-        if gpgv is None:
+        if not gpgv:
             gpgv = '/usr/bin/gpgv'
         if not os.access(gpgv, os.X_OK):
-            raise GPGSigVerifierException("Couldn't execute \"%s\"" % (gpgv,))
+            raise GPGSigVerifierException("Couldn't execute \"%s\"" % gpgv)
         self._gpgv = gpgv
 
     def verify(self, filename, sigfilename=None):
@@ -53,25 +53,24 @@ class GPGSigVerifier:
             os.close(stdin)
             misc.dup2(stdout, 1)
             misc.dup2(stdout, 2)
-            args = []
+            args = [self._gpgv]
             for keyring in self._keyrings:
-                args.append('--keyring')
-                args.append(keyring)
+                args.extend(['--keyring', keyring])
             if sigfilename:
                 args.append(sigfilename)
-            args = [self._gpgv] + args + [filename]
+            args.append(filename)
             os.execv(self._gpgv, args)
             os.exit(1)
         os.close(stdout)
         output = os.fdopen(stdin).readlines()
         (pid, status) = os.waitpid(pid, 0)
-        if not (status is None or (os.WIFEXITED(status) and os.WEXITSTATUS(status) == 0)):
+        if status or (not os.WIFEXITED(status) and os.WEXITSTATUS(status) != 0):
             if os.WIFEXITED(status):
-                msg = "gpgv exited with error code %d" % (os.WEXITSTATUS(status),)
+                msg = "gpgv exited with error code %d" % os.WEXITSTATUS(status)
             elif os.WIFSTOPPED(status):
-                msg = "gpgv stopped unexpectedly with signal %d" % (os.WSTOPSIG(status),)
+                msg = "gpgv stopped unexpectedly with signal %d" % os.WSTOPSIG(status)
             elif os.WIFSIGNALED(status):
-                msg = "gpgv died with signal %d" % (os.WTERMSIG(status),)
+                msg = "gpgv died with signal %d" % os.WTERMSIG(status)
             raise GPGSigVerificationFailure(msg, output)
         return output
 
diff --git a/minidinstall/OrderedDict.py b/minidinstall/OrderedDict.py
index 7c842b0..dab57db 100644
--- a/minidinstall/OrderedDict.py
+++ b/minidinstall/OrderedDict.py
@@ -1,10 +1,10 @@
-# OrderedDict.py
+# OrderedDict -*- mode: python; coding: utf-8 -*-
 #
 # This class functions almost exactly like UserDict.  However, when using
 # the sequence methods, it returns items in the same order in which they
 # were added, instead of some random order.
 #
-# Copyright 2001 Adam Heath <doogie@debian.org>
+# Copyright (c) 2001 Adam Heath <doogie@debian.org>
 #
 # This file is free software; you can redistribute it and/or modify it
 # under the terms of the GNU General Public License as published by
@@ -28,7 +28,7 @@ class OrderedDict(UserDict):
     def __init__(self, dict=None):
         UserDict.__init__(self)
         self.__order=[]
-        if dict is not None and dict.__class__ is not None:
+        if dict and dict.__class__:
             self.update(dict)
 
     def __cmp__(self, dict):
@@ -57,8 +57,7 @@ class OrderedDict(UserDict):
     def copy(self):
         if self.__class__ is OrderedDict:
             return OrderedDict(self)
-        import copy
-        return copy.copy(self)
+        return self.copy()
 
     def keys(self):
         return self.__order
@@ -70,7 +69,7 @@ class OrderedDict(UserDict):
         return list(map(lambda x, self=self: self.__getitem__(x), self.__order))
 
     def update(self, dict):
-        for k, v in list(dict.items()):
+        for (k, v) in list(dict.items()):
             self.__setitem__(k, v)
 
 # vim:ts=4:sw=4:et:
diff --git a/minidinstall/SafeWriteFile.py b/minidinstall/SafeWriteFile.py
index 591c4f0..38262f2 100755
--- a/minidinstall/SafeWriteFile.py
+++ b/minidinstall/SafeWriteFile.py
@@ -1,11 +1,12 @@
-# SafeWriteFile.py
+#!/usr/bin/python3
+# SafeWriteFile -*- mode: python; coding: utf-8 -*-
 #
 # This file is a writable file object.  It writes to a specified newname,
 # and when closed, renames the file to the realname.  If the object is
 # deleted, without being closed, this rename isn't done.  If abort() is
 # called, it also disables the rename.
 #
-# Copyright 2001 Adam Heath <doogie@debian.org>
+# Copyright (c) 2001 Adam Heath <doogie@debian.org>
 #
 # This file is free software; you can redistribute it and/or modify it
 # under the terms of the GNU General Public License as published by
@@ -27,11 +28,9 @@ from os import rename
 class ObjectNotAllowed(Exception):
     pass
 
-
 class InvalidMode(Exception):
     pass
 
-
 class SafeWriteFile:
     def __init__(self, newname, realname, mode="w", bufsize=-1):
 
@@ -47,7 +46,7 @@ class SafeWriteFile:
         self.fobj=open(newname, mode, bufsize)
         self.newname=newname
         self.realname=realname
-        self.__abort=0
+        self.__abort=False
 
     def close(self):
         self.fobj.close()
@@ -55,7 +54,7 @@ class SafeWriteFile:
             rename(self.newname, self.realname)
 
     def abort(self):
-        self.__abort=1
+        self.__abort=True
 
     def __del__(self):
         self.abort()
@@ -67,7 +66,6 @@ class SafeWriteFile:
         except:
             return eval("self.fobj." + attr)
 
-
 if __name__ == "__main__":
     import time
     f=SafeWriteFile("sf.new", "sf.data")
diff --git a/minidinstall/SignedFile.py b/minidinstall/SignedFile.py
index efc4730..5a1f7f6 100755
--- a/minidinstall/SignedFile.py
+++ b/minidinstall/SignedFile.py
@@ -1,9 +1,10 @@
+#!/usr/bin/python3
 # SignedFile -*- mode: python; coding: utf-8 -*-
 
 # SignedFile offers a subset of file object operations, and is
 # designed to transparently handle files with PGP signatures.
 
-# Copyright © 2002 Colin Walters <walters@gnu.org>
+# Copyright (c) 2002 Colin Walters <walters@gnu.org>
 #
 # This file is free software; you can redistribute it and/or modify it
 # under the terms of the GNU General Public License as published by
@@ -19,23 +20,22 @@
 # along with this program; if not, write to the Free Software
 # Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
-import re,string
-
 class SignedFile:
     _stream = None
-    _eof = 0
-    _signed = 0
+    _eof = False
+    _signed = False
     _signature = None
     _signatureversion = None
     _initline = None
+
     def __init__(self, stream):
         self._stream = stream
         line = stream.readline()
-        if (line == "-----BEGIN PGP SIGNED MESSAGE-----\n"):
-            self._signed = 1
+        if line == "-----BEGIN PGP SIGNED MESSAGE-----\n":
+            self._signed = True
             while True:
                 line = stream.readline()
-                if (len(line) == 0 or line == '\n'):
+                if not line or line == '\n':
                     break
         else:
             self._initline = line
@@ -51,13 +51,13 @@ class SignedFile:
         if not self._signed:
             return line
         elif line == "-----BEGIN PGP SIGNATURE-----\n":
-            self._eof = 1
+            self._eof = True
             self._signature = []
             self._signatureversion = self._stream.readline()
             self._stream.readline()  # skip blank line
             while True:
                 line = self._stream.readline()
-                if len(line) == 0 or line == "-----END PGP SIGNATURE-----\n":
+                if not line or line == "-----END PGP SIGNATURE-----\n":
                     break
                 self._signature.append(line)
             self._signature = ''.join(self._signature)
@@ -68,7 +68,7 @@ class SignedFile:
         ret = []
         while True:
             line = self.readline()
-            if (line != ''):
+            if line:
                 ret.append(line)
             else:
                 break
@@ -86,22 +86,22 @@ class SignedFile:
     def getSignatureVersion(self):
         return self._signatureversion
 
-if __name__=="__main__":
+if __name__ == "__main__":
     import sys
-    if len(sys.argv) == 0:
+    if not sys.argv:
         print("Need one file as an argument")
         sys.exit(1)
     filename = sys.argv[1]
-    f=SignedFile(open(filename))
+    f = SignedFile(open(filename))
     if f.getSigned():
         print("**** SIGNED ****")
     else:
         print("**** NOT SIGNED ****")
-    lines=f.readlines()
+    lines = f.readlines()
     print(lines)
     if not f.getSigned():
         assert(len(lines) == len(actuallines))
     else:
-        print("Signature: %s" % (f.getSignature()))
+        print("Signature: %s" % f.getSignature())
 
 # vim:ts=4:sw=4:et:
diff --git a/minidinstall/mail.py b/minidinstall/mail.py
index 50df462..305d822 100644
--- a/minidinstall/mail.py
+++ b/minidinstall/mail.py
@@ -1,8 +1,8 @@
 # mail -*- mode: python; coding: utf-8 -*-
 
-"""Simple mail support for mini-dinstall."""
+# Simple mail support for mini-dinstall.
 
-# Copyright © 2008 Stephan Sürken <absurd@debian.org>
+# Copyright (c) 2008 Stephan Sürken <absurd@debian.org>
 
 # This file is free software; you can redistribute it and/or modify it
 # under the terms of the GNU General Public License as published by
@@ -21,24 +21,22 @@
 import smtplib
 import email.mime.text
 import email.utils
-
 import logging
 
 def send(smtp_server, smtp_from, smtp_to, body, subject="mini-dinstall mail notice"):
     """Send email; on error, log and continue."""
-
     logger = logging.getLogger("mini-dinstall")
 
-    try:
-        # Create a mime body
-        mime_body = email.mime.text.MIMEText(body, 'plain', 'utf-8')
-        mime_body['Subject'] = subject
-        mime_body['From'] = smtp_from
-        mime_body['To'] = smtp_to
-        mime_body['Date'] = email.utils.formatdate(localtime=True)
-        mime_body['Message-ID'] = email.utils.make_msgid()
-        mime_body.add_header('X-Mini-Dinstall', 'YES')
+    # Create a mime body
+    mime_body = email.mime.text.MIMEText(body, 'plain', 'utf-8')
+    mime_body['Subject'] = subject
+    mime_body['From'] = smtp_from
+    mime_body['To'] = smtp_to
+    mime_body['Date'] = email.utils.formatdate(localtime=True)
+    mime_body['Message-ID'] = email.utils.make_msgid()
+    mime_body.add_header('X-Mini-Dinstall', 'YES')
 
+    try:
         # Send via SMTP server
         smtp = smtplib.SMTP(smtp_server)
         smtp.sendmail(smtp_from, [smtp_to], mime_body.as_string())
diff --git a/minidinstall/misc.py b/minidinstall/misc.py
index 372c450..5f7fb71 100644
--- a/minidinstall/misc.py
+++ b/minidinstall/misc.py
@@ -2,7 +2,7 @@
 
 # misc tools for mini-dinstall
 
-# Copyright © 2004 Thomas Viehmann <tv@beamnet.de>
+# Copyright (c) 2004 Thomas Viehmann <tv@beamnet.de>
 
 # This file is free software; you can redistribute it and/or modify it
 # under the terms of the GNU General Public License as published by
@@ -18,26 +18,25 @@
 # along with this program; if not, write to the Free Software
 # Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
-import os, errno, time, string, re, hashlib
+import os, errno, time, re, hashlib
 
-def dup2(fd,fd2):
+def dup2(fd, fd2):
     # dup2 with EBUSY retries (cf. dup2(2) and Debian bug #265513)
-    success = 0
+    success = False
     tries = 0
-    while (not success):
+    while not success:
         try:
-            os.dup2(fd,fd2)
-            success = 1
+            os.dup2(fd, fd2)
+            success = True
         except OSError as e:
-            if (e.errno != errno.EBUSY) or (tries >= 3):
+            if e.errno != errno.EBUSY or tries >= 3:
                 raise
-            # wait 0-2 seconds befor next try
+            # wait 0-2 seconds before next try
             time.sleep(tries)
             tries += 1
 
 def format_changes(L):
     """ remove changelog header and all lines with only a dot """
-
     dotmatch = re.compile('^\.$')
     L1 = []
 
@@ -48,16 +47,11 @@ def format_changes(L):
 
 def get_file_sum(self, type, filename):
     """ generate hash sums for file """
-    if type == 'md5':
-        sum = hashlib.md5()
-    elif type == 'sha1':
-        sum = hashlib.sha1()
-    elif type == 'sha256':
-        sum = hashlib.sha256()
+    sum = getattr(hashlib, type)()
     self._logger.debug("Generate %s (python-internal) for %s" % (type, filename))
-    f = open(filename,'rb')
+    f = open(filename, 'rb')
     buf = f.read(8192)
-    while buf != '':
+    while buf:
         sum.update(buf)
         buf = f.read(8192)
     return sum.hexdigest()
diff --git a/minidinstall/tweet.py b/minidinstall/tweet.py
index 7106085..3a4a4ef 100644
--- a/minidinstall/tweet.py
+++ b/minidinstall/tweet.py
@@ -1,8 +1,8 @@
-# mail -*- mode: python; coding: utf-8 -*-
+# tweet -*- mode: python; coding: utf-8 -*-
 
-"""Simple tweet support for mini-dinstall."""
+# Simple tweet support for mini-dinstall.
 
-# Copyright © 2010 Christopher R. Gabriel <cgabriel@truelite.it>
+# Copyright (c) 2010 Christopher R. Gabriel <cgabriel@truelite.it>
 
 # This file is free software; you can redistribute it and/or modify it
 # under the terms of the GNU General Public License as published by
@@ -18,10 +18,8 @@
 # along with this program; if not, write to the Free Software
 # Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
-
 import logging
 import urllib.request
-import base64
 
 def send(tweet_body, tweet_server, tweet_user, tweet_password):
     """Send tweet; on error, log and continue."""
@@ -37,8 +35,8 @@ def send(tweet_body, tweet_server, tweet_user, tweet_password):
 
     if not post_url:
         logger.exception("Unknown tweet site")
-    if not tweet_user or not tweet_password:
-        logger.exception("Missing username or password for twitting")
+    if not (tweet_user and tweet_password):
+        logger.exception("Missing username or password for tweeting")
 
     auth_handler = urllib.request.HTTPBasicAuthHandler()
     auth_handler.add_password(realm=auth_realm,
@@ -49,10 +47,9 @@ def send(tweet_body, tweet_server, tweet_user, tweet_password):
 
     req = urllib.request.Request(post_url)
     req.add_data("status=%s" % tweet_body)
-    handle = None
     try:
         handle = m_http_opener.open(req)
-        a = handle.read()
+        result = handle.read()
         logger.info("Tweet sent to %s (%s)" % (tweet_server, tweet_user))
     except Exception as e:
-        logger.exception("Error sending tweet to %s ('%s') via %s: %s: %s", tweet_server, tweet_body, tweet_user, type(e), e.args)
+        logger.exception("Error sending tweet to %s ('%s') via %s: %s: %s" % (tweet_server, tweet_body, tweet_user, type(e), e.args))