factotum: use try/except/finally

hgext/factotum.py

@@ -1,127 +1,126 b''
 # factotum.py - Plan 9 factotum integration for Mercurial
 #
 # Copyright (C) 2012 Steven Stallion <[e-mail]>
 #
 # This program 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 (at your
 # option) any later version.
 #
 # This program is distributed in the hope that it will be useful, but
 # WITHOUT ANY WARRANTY; without even the implied warranty of
 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General
 # Public License for more details.
 #
 # You should have received a copy of the GNU General Public License along
 # with this program; if not, write to the Free Software Foundation, Inc.,
 # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 
 '''http authentication with factotum
 
 This extension allows the factotum(4) facility on Plan 9 from Bell Labs
 platforms to provide authentication information for HTTP access. Configuration
 entries specified in the auth section as well as authentication information
 provided in the repository URL are fully supported. If no prefix is specified,
 a value of "*" will be assumed.
 
 By default, keys are specified as::
 
   proto=pass service=hg prefix=<prefix> user=<username> !password=<password>
 
 If the factotum extension is unable to read the required key, one will be
 requested interactively.
 
 A configuration section is available to customize runtime behavior. By
 default, these entries are::
 
   [factotum]
   executable = /bin/auth/factotum
   mountpoint = /mnt/factotum
   service = hg
 
 The executable entry defines the full path to the factotum binary. The
 mountpoint entry defines the path to the factotum file service. Lastly, the
 service entry controls the service name used when reading keys.
 
 '''
 
 from mercurial.i18n import _
 from mercurial.url import passwordmgr
 from mercurial import httpconnection, util
 import os, urllib2
 
 ERRMAX = 128
 
 _executable = _mountpoint = _service = None
 
 def auth_getkey(self, params):
     if not self.ui.interactive():
         raise util.Abort(_('factotum not interactive'))
     if 'user=' not in params:
         params = '%s user?' % params
     params = '%s !password?' % params
     os.system("%s -g '%s'" % (_executable, params))
 
 def auth_getuserpasswd(self, getkey, params):
     params = 'proto=pass %s' % params
     while True:
         fd = os.open('%s/rpc' % _mountpoint, os.O_RDWR)
         try:
-            try:
-                os.write(fd, 'start %s' % params)
-                l = os.read(fd, ERRMAX).split()
-                if l[0] == 'ok':
-                    os.write(fd, 'read')
-                    status, user, passwd = os.read(fd, ERRMAX).split(None, 2)
-                    if status == 'ok':
-                        if passwd.startswith("'"):
-                            if passwd.endswith("'"):
-                                passwd = passwd[1:-1].replace("''", "'")
-                            else:
-                                raise util.Abort(_('malformed password string'))
-                        return (user, passwd)
-            except (OSError, IOError):
-                raise util.Abort(_('factotum not responding'))
+            os.write(fd, 'start %s' % params)
+            l = os.read(fd, ERRMAX).split()
+            if l[0] == 'ok':
+                os.write(fd, 'read')
+                status, user, passwd = os.read(fd, ERRMAX).split(None, 2)
+                if status == 'ok':
+                    if passwd.startswith("'"):
+                        if passwd.endswith("'"):
+                            passwd = passwd[1:-1].replace("''", "'")
+                        else:
+                            raise util.Abort(_('malformed password string'))
+                    return (user, passwd)
+        except (OSError, IOError):
+            raise util.Abort(_('factotum not responding'))
         finally:
             os.close(fd)
         getkey(self, params)
 
 def monkeypatch_method(cls):
     def decorator(func):
         setattr(cls, func.__name__, func)
         return func
     return decorator
 
 @monkeypatch_method(passwordmgr)
 def find_user_password(self, realm, authuri):
     user, passwd = urllib2.HTTPPasswordMgrWithDefaultRealm.find_user_password(
         self, realm, authuri)
     if user and passwd:
         self._writedebug(user, passwd)
         return (user, passwd)
 
     prefix = ''
     res = httpconnection.readauthforuri(self.ui, authuri, user)
     if res:
         _, auth = res
         prefix = auth.get('prefix')
         user, passwd = auth.get('username'), auth.get('password')
     if not user or not passwd:
         if not prefix:
             prefix = realm.split(' ')[0].lower()
         params = 'service=%s prefix=%s' % (_service, prefix)
         if user:
             params = '%s user=%s' % (params, user)
         user, passwd = auth_getuserpasswd(self, auth_getkey, params)
 
     self.add_password(realm, authuri, user, passwd)
     self._writedebug(user, passwd)
     return (user, passwd)
 
 def uisetup(ui):
     global _executable
     _executable = ui.config('factotum', 'executable', '/bin/auth/factotum')
     global _mountpoint
     _mountpoint = ui.config('factotum', 'mountpoint', '/mnt/factotum')
     global _service
     _service = ui.config('factotum', 'service', 'hg')