From b271c5ea72f6bc33a914fa511a23958be6ee1113 Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Wed, 25 Jan 2012 10:15:18 +0530
Subject: [PATCH] Allow calibre to be run simultaneously in two different user
 accounts on windows. Fixes #919856 (Python function terminated unexpectedly
 [Error 5]  Access is denied (Error Code: 1))

---
 src/calibre/constants.py          | 23 +++++++++++++++++++
 src/calibre/gui2/main.py          | 14 ++++++------
 src/calibre/utils/ipc/__init__.py | 37 ++++++++++++++++++++++---------
 3 files changed, 56 insertions(+), 18 deletions(-)

diff --git a/src/calibre/constants.py b/src/calibre/constants.py
index 0bae1d2c86..902dc057df 100644
--- a/src/calibre/constants.py
+++ b/src/calibre/constants.py
@@ -161,4 +161,27 @@ def get_version():
         v += '*'
     return v
 
+def get_unicode_windows_env_var(name):
+    import ctypes
+    name = unicode(name)
+    n = ctypes.windll.kernel32.GetEnvironmentVariableW(name, None, 0)
+    if n == 0:
+        return None
+    buf = ctypes.create_unicode_buffer(u'\0'*n)
+    ctypes.windll.kernel32.GetEnvironmentVariableW(name, buf, n)
+    return buf.value
 
+def get_windows_username():
+    import ctypes
+    try:
+        advapi32 = ctypes.windll.advapi32
+        GetUserName = getattr(advapi32, u'GetUserNameW')
+    except AttributeError:
+        pass
+    else:
+        buf = ctypes.create_unicode_buffer(257)
+        n = ctypes.c_int(257)
+        if GetUserName(buf, ctypes.byref(n)):
+            return buf.value
+
+    return get_unicode_windows_env_var(u'USERNAME')
diff --git a/src/calibre/gui2/main.py b/src/calibre/gui2/main.py
index 9e1b6b4b24..195be03626 100644
--- a/src/calibre/gui2/main.py
+++ b/src/calibre/gui2/main.py
@@ -10,7 +10,7 @@ from PyQt4.Qt import (QCoreApplication, QIcon, QObject, QTimer,
 from calibre import prints, plugins, force_unicode
 from calibre.constants import (iswindows, __appname__, isosx, DEBUG,
         filesystem_encoding)
-from calibre.utils.ipc import ADDRESS, RC
+from calibre.utils.ipc import gui_socket_address, RC
 from calibre.gui2 import (ORG_NAME, APP_UID, initialize_file_icon_provider,
     Application, choose_dir, error_dialog, question_dialog, gprefs)
 from calibre.gui2.main_window import option_parser as _option_parser
@@ -304,7 +304,7 @@ def cant_start(msg=_('If you are sure it is not running')+', ',
         if iswindows:
             what = _('try rebooting your computer.')
         else:
-            what = _('try deleting the file')+': '+ADDRESS
+            what = _('try deleting the file')+': '+ gui_socket_address()
 
     info = base%(where, msg, what)
     error_dialog(None, _('Cannot Start ')+__appname__,
@@ -345,14 +345,14 @@ def main(args=sys.argv):
         return 0
     if si:
         try:
-            listener = Listener(address=ADDRESS)
+            listener = Listener(address=gui_socket_address())
         except socket.error:
             if iswindows:
                 cant_start()
-            if os.path.exists(ADDRESS):
-                os.remove(ADDRESS)
+            if os.path.exists(gui_socket_address()):
+                os.remove(gui_socket_address())
             try:
-                listener = Listener(address=ADDRESS)
+                listener = Listener(address=gui_socket_address())
             except socket.error:
                 cant_start()
             else:
@@ -363,7 +363,7 @@ def main(args=sys.argv):
                     gui_debug=gui_debug)
     otherinstance = False
     try:
-        listener = Listener(address=ADDRESS)
+        listener = Listener(address=gui_socket_address())
     except socket.error: # Good si is correct (on UNIX)
         otherinstance = True
     else:
diff --git a/src/calibre/utils/ipc/__init__.py b/src/calibre/utils/ipc/__init__.py
index 2df13ce7c8..93db2e9fc7 100644
--- a/src/calibre/utils/ipc/__init__.py
+++ b/src/calibre/utils/ipc/__init__.py
@@ -9,17 +9,32 @@ __docformat__ = 'restructuredtext en'
 import os
 from threading import Thread
 
-from calibre.constants import iswindows
+from calibre.constants import iswindows, get_windows_username
 
-if iswindows:
-    ADDRESS = r'\\.\pipe\CalibreGUI'
-else:
-    from tempfile import gettempdir
-    tmp = gettempdir()
-    user = os.environ.get('USER', '')
-    if not user:
-        user = os.path.basename(os.path.expanduser('~'))
-    ADDRESS = os.path.join(tmp, user+'-calibre-gui.socket')
+ADDRESS = None
+
+def gui_socket_address():
+    global ADDRESS
+    if ADDRESS is None:
+        if iswindows:
+            ADDRESS = r'\\.\pipe\CalibreGUI'
+            try:
+                user = get_windows_username()
+            except:
+                user = None
+            if user:
+                from calibre.utils.filenames import ascii_filename
+                user = ascii_filename(user).replace(' ', '_')
+                if user:
+                    ADDRESS += '-' + user[:100] + 'x'
+        else:
+            from tempfile import gettempdir
+            tmp = gettempdir()
+            user = os.environ.get('USER', '')
+            if not user:
+                user = os.path.basename(os.path.expanduser('~'))
+            ADDRESS = os.path.join(tmp, user+'-calibre-gui.socket')
+    return ADDRESS
 
 class RC(Thread):
 
@@ -32,7 +47,7 @@ class RC(Thread):
         from multiprocessing.connection import Client
         self.done = False
         try:
-            self.conn = Client(ADDRESS)
+            self.conn = Client(gui_socket_address())
             self.done = True
         except:
             if self.print_error: