From ad3156a58fc073f130ceaa96a9257a64d63e3d39 Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Fri, 12 Jul 2019 20:10:15 +0530
Subject: [PATCH] Fix a regression caused by py3 porting that is preventing
 calibre from starting up on windows machines with non UTF-8 locales. Fixes
 #1836360 [no RUN ver 3.45.0 or
 3.45.1](https://bugs.launchpad.net/calibre/+bug/1836360)

os.path.expanduser is broken in python2. When passed a unicode object it
concatenates it to a bytestring, which will lead to UnicodeDecodeError
if the bytestring happens to not be in the default encoding, ususally
UTF-8
---
 src/calibre/startup.py         | 22 ++++++++++++++++++++--
 src/calibre/utils/filenames.py | 17 ++---------------
 2 files changed, 22 insertions(+), 17 deletions(-)

diff --git a/src/calibre/startup.py b/src/calibre/startup.py
index b6c662ef6d..7508b24395 100644
--- a/src/calibre/startup.py
+++ b/src/calibre/startup.py
@@ -7,7 +7,7 @@ __docformat__ = 'restructuredtext en'
 Perform various initialization tasks.
 '''
 
-import locale, sys
+import locale, sys, os
 
 # Default translation is NOOP
 from polyglot.builtins import builtins, is_py3, unicode_type
@@ -79,7 +79,25 @@ if not _run_once:
         if len(sys.argv) > 1 and not isinstance(sys.argv[1], unicode_type):
             sys.argv[1:] = winutil.argv()[1-len(sys.argv):]
 
-    #
+        if not ispy3:
+            # Python2's expanduser is broken for non-ASCII usernames
+            # and unicode paths
+
+            def expanduser(path):
+                if isinstance(path, bytes):
+                    path = path.decode('mbcs')
+                if path[:1] != '~':
+                    return path
+                i, n = 1, len(path)
+                while i < n and path[i] not in '/\\':
+                    i += 1
+                userhome = winutil.special_folder_path(winutil.CSIDL_PROFILE)
+                if i != 1:  # ~user
+                    userhome = os.path.join(os.path.dirname(userhome), path[1:i])
+
+                return userhome + path[i:]
+            os.path.expanduser = expanduser
+
     # Ensure that all temp files/dirs are created under a calibre tmp dir
     from calibre.ptempfile import base_dir
     try:
diff --git a/src/calibre/utils/filenames.py b/src/calibre/utils/filenames.py
index 1d2417e6d9..93236af4f5 100644
--- a/src/calibre/utils/filenames.py
+++ b/src/calibre/utils/filenames.py
@@ -12,7 +12,7 @@ from math import ceil
 
 from calibre import force_unicode, isbytestring, prints, sanitize_file_name
 from calibre.constants import (
-    filesystem_encoding, iswindows, plugins, preferred_encoding, isosx, ispy3
+    filesystem_encoding, iswindows, plugins, preferred_encoding, isosx
 )
 from calibre.utils.localization import get_udc
 from polyglot.builtins import iteritems, itervalues, unicode_type, range
@@ -545,20 +545,7 @@ def remove_dir_if_empty(path, ignore_metadata_caches=False):
         raise
 
 
-if iswindows and not ispy3:
-    # Python's expanduser is broken for non-ASCII usernames
-    def expanduser(path):
-        if isinstance(path, bytes):
-            path = path.decode(filesystem_encoding)
-        if path[:1] != '~':
-            return path
-        i, n = 1, len(path)
-        while i < n and path[i] not in '/\\':
-            i += 1
-        userhome = plugins['winutil'][0].special_folder_path(plugins['winutil'][0].CSIDL_PROFILE)
-        return userhome + path[i:]
-else:
-    expanduser = os.path.expanduser
+expanduser = os.path.expanduser
 
 
 def format_permissions(st_mode):