python: fix error handling

[notmuch] / bindings / python / notmuch / database.py

diff --git a/bindings/python/notmuch/database.py b/bindings/python/notmuch/database.py
index bafe497e02c4f0466b3e230f0ce3117148edafea..6238b2891e066cf76a9361fc573509a287851124 100644 (file)
--- a/bindings/python/notmuch/database.py
+++ b/bindings/python/notmuch/database.py
@@ -18,20 +18,41 @@ Copyright 2010 Sebastian Spaeth <Sebastian@SSpaeth.de>'
 """
 
 import os
 """
 
 import os

-from ctypes import c_int, c_char_p, c_void_p, c_uint, c_long, byref
-from notmuch.globals import nmlib, STATUS, NotmuchError, Enum, _str
+from ctypes import c_char_p, c_void_p, c_uint, c_long, byref, POINTER
+from notmuch.globals import (nmlib, STATUS, NotmuchError, NotInitializedError,
+     NullPointerError, Enum, _str,
+     NotmuchDatabaseP, NotmuchDirectoryP, NotmuchMessageP, NotmuchTagsP,
+     NotmuchQueryP, NotmuchMessagesP, NotmuchThreadsP, NotmuchFilenamesP)

 from notmuch.thread import Threads
 from notmuch.message import Messages, Message
 from notmuch.tag import Tags
 
 from notmuch.thread import Threads
 from notmuch.message import Messages, Message
 from notmuch.tag import Tags
 

-class Database(object):
-    """Represents a notmuch database (wraps notmuch_database_t)

 
 

-    .. note:: Do remember that as soon as we tear down this object,
-           all underlying derived objects such as queries, threads,
-           messages, tags etc will be freed by the underlying library
-           as well. Accessing these objects will lead to segfaults and
-           other unexpected behavior. See above for more details.
+class Database(object):
+    """The :class:`Database` is the highest-level object that notmuch
+    provides. It references a notmuch database, and can be opened in
+    read-only or read-write mode. A :class:`Query` can be derived from
+    or be applied to a specific database to find messages. Also adding
+    and removing messages to the database happens via this
+    object. Modifications to the database are not atmic by default (see
+    :meth:`begin_atomic`) and once a database has been modified, all
+    other database objects pointing to the same data-base will throw an
+    :exc:`XapianError` as the underlying database has been
+    modified. Close and reopen the database to continue working with it.
+
+    .. note::
+
+        Any function in this class can and will throw an
+        :exc:`NotInitializedError` if the database was not intitialized
+        properly.
+
+    .. note::
+
+        Do remember that as soon as we tear down (e.g. via `del db`) this
+        object, all underlying derived objects such as queries, threads,
+        messages, tags etc will be freed by the underlying library as well.
+        Accessing these objects will lead to segfaults and other unexpected
+        behavior. See above for more details.

     """
     _std_db_path = None
     """Class attribute to cache user's default database"""
     """
     _std_db_path = None
     """Class attribute to cache user's default database"""


@@ -41,39 +62,50 @@ class Database(object):
 
     """notmuch_database_get_directory"""
     _get_directory = nmlib.notmuch_database_get_directory
 
     """notmuch_database_get_directory"""
     _get_directory = nmlib.notmuch_database_get_directory

-    _get_directory.restype = c_void_p
+    _get_directory.argtypes = [NotmuchDatabaseP, c_char_p]
+    _get_directory.restype = NotmuchDirectoryP

 
     """notmuch_database_get_path"""
     _get_path = nmlib.notmuch_database_get_path
 
     """notmuch_database_get_path"""
     _get_path = nmlib.notmuch_database_get_path

+    _get_path.argtypes = [NotmuchDatabaseP]

     _get_path.restype = c_char_p
 
     """notmuch_database_get_version"""
     _get_version = nmlib.notmuch_database_get_version
     _get_path.restype = c_char_p
 
     """notmuch_database_get_version"""
     _get_version = nmlib.notmuch_database_get_version

+    _get_version.argtypes = [NotmuchDatabaseP]

     _get_version.restype = c_uint
 
     """notmuch_database_open"""
     _open = nmlib.notmuch_database_open
     _get_version.restype = c_uint
 
     """notmuch_database_open"""
     _open = nmlib.notmuch_database_open

-    _open.restype = c_void_p
+    _open.argtypes = [c_char_p, c_uint]
+    _open.restype = NotmuchDatabaseP

 
     """notmuch_database_upgrade"""
     _upgrade = nmlib.notmuch_database_upgrade
 
     """notmuch_database_upgrade"""
     _upgrade = nmlib.notmuch_database_upgrade

-    _upgrade.argtypes = [c_void_p, c_void_p, c_void_p]
+    _upgrade.argtypes = [NotmuchDatabaseP, c_void_p, c_void_p]
+    _upgrade.restype = c_uint

 
     """ notmuch_database_find_message"""
     _find_message = nmlib.notmuch_database_find_message
 
     """ notmuch_database_find_message"""
     _find_message = nmlib.notmuch_database_find_message

-    _find_message.restype = c_void_p
+    _find_message.argtypes = [NotmuchDatabaseP, c_char_p,
+                              POINTER(NotmuchMessageP)]
+    _find_message.restype = c_uint

 
     """notmuch_database_find_message_by_filename"""
     _find_message_by_filename = nmlib.notmuch_database_find_message_by_filename
 
     """notmuch_database_find_message_by_filename"""
     _find_message_by_filename = nmlib.notmuch_database_find_message_by_filename

-    _find_message_by_filename.restype = c_void_p
+    _find_message_by_filename.argtypes = [NotmuchDatabaseP, c_char_p,
+                                          POINTER(NotmuchMessageP)]
+    _find_message_by_filename.restype = c_uint

 
     """notmuch_database_get_all_tags"""
     _get_all_tags = nmlib.notmuch_database_get_all_tags
 
     """notmuch_database_get_all_tags"""
     _get_all_tags = nmlib.notmuch_database_get_all_tags

-    _get_all_tags.restype = c_void_p
+    _get_all_tags.argtypes = [NotmuchDatabaseP]
+    _get_all_tags.restype = NotmuchTagsP

 
     """notmuch_database_create"""
     _create = nmlib.notmuch_database_create
 
     """notmuch_database_create"""
     _create = nmlib.notmuch_database_create

-    _create.restype = c_void_p
+    _create.argtypes = [c_char_p]
+    _create.restype = NotmuchDatabaseP

 
     def __init__(self, path=None, create=False, mode=0):
         """If *path* is `None`, we will try to read a users notmuch
 
     def __init__(self, path=None, create=False, mode=0):
         """If *path* is `None`, we will try to read a users notmuch


@@ -93,8 +125,8 @@ class Database(object):
         :param mode:   Mode to open a database in. Is always
                        :attr:`MODE`.READ_WRITE when creating a new one.
         :type mode:    :attr:`MODE`
         :param mode:   Mode to open a database in. Is always
                        :attr:`MODE`.READ_WRITE when creating a new one.
         :type mode:    :attr:`MODE`

-        :returns:      Nothing
-        :exception:    :exc:`NotmuchError` in case of failure.
+        :exception: :exc:`NotmuchError` or derived exception in case of
+            failure.

         """
         self._db = None
         if path is None:
         """
         self._db = None
         if path is None:


@@ -109,10 +141,10 @@ class Database(object):
         else:
             self.create(path)
 
         else:
             self.create(path)
 

-    def _verify_initialized_db(self):
-        """Raises a NotmuchError in case self._db is still None"""
+    def _assert_db_is_initialized(self):
+        """Raises :exc:`NotInitializedError` if self._db is `None`"""

         if self._db is None:
         if self._db is None:

-            raise NotmuchError(STATUS.NOT_INITIALIZED)
+            raise NotInitializedError()

 
     def create(self, path):
         """Creates a new notmuch database
 
     def create(self, path):
         """Creates a new notmuch database


@@ -128,7 +160,7 @@ class Database(object):
         :type path: str
         :returns: Nothing
         :exception: :exc:`NotmuchError` in case of any failure
         :type path: str
         :returns: Nothing
         :exception: :exc:`NotmuchError` in case of any failure

-                    (after printing an error message on stderr).
+                    (possibly after printing an error message on stderr).

         """
         if self._db is not None:
             raise NotmuchError(message="Cannot create db, this Database() "
         """
         if self._db is not None:
             raise NotmuchError(message="Cannot create db, this Database() "


@@ -136,7 +168,7 @@ class Database(object):
 
         res = Database._create(_str(path), Database.MODE.READ_WRITE)
 
 
         res = Database._create(_str(path), Database.MODE.READ_WRITE)
 

-        if res is None:
+        if not res:

             raise NotmuchError(
                 message="Could not create the specified database")
         self._db = res
             raise NotmuchError(
                 message="Could not create the specified database")
         self._db = res


@@ -151,37 +183,32 @@ class Database(object):
         :param status: Open the database in read-only or read-write mode
         :type status:  :attr:`MODE`
         :returns: Nothing
         :param status: Open the database in read-only or read-write mode
         :type status:  :attr:`MODE`
         :returns: Nothing

-        :exception: Raises :exc:`NotmuchError` in case
-                    of any failure (after printing an error message on stderr).
+        :exception: Raises :exc:`NotmuchError` in case of any failure
+                    (possibly after printing an error message on stderr).

         """
         res = Database._open(_str(path), mode)
 
         """
         res = Database._open(_str(path), mode)
 

-        if res is None:
-            raise NotmuchError(
-                message="Could not open the specified database")
+        if not res:
+            raise NotmuchError(message="Could not open the specified database")

         self._db = res
 
     def get_path(self):
         self._db = res
 
     def get_path(self):

-        """Returns the file path of an open database
-
-        Wraps *notmuch_database_get_path*."""
-        # Raise a NotmuchError if not initialized
-        self._verify_initialized_db()
-
+        """Returns the file path of an open database"""
+        self._assert_db_is_initialized()

         return Database._get_path(self._db).decode('utf-8')
 
     def get_version(self):
         """Returns the database format version
 
         :returns: The database version as positive integer
         return Database._get_path(self._db).decode('utf-8')
 
     def get_version(self):
         """Returns the database format version
 
         :returns: The database version as positive integer

-        :exception: :exc:`NotmuchError` with STATUS.NOT_INITIALIZED if
-                    the database was not intitialized.

         """
         """

-        # Raise a NotmuchError if not initialized
-        self._verify_initialized_db()
-
+        self._assert_db_is_initialized()

         return Database._get_version(self._db)
 
         return Database._get_version(self._db)
 

+    _needs_upgrade = nmlib.notmuch_database_needs_upgrade
+    _needs_upgrade.argtypes = [NotmuchDatabaseP]
+    _needs_upgrade.restype = bool
+

     def needs_upgrade(self):
         """Does this database need to be upgraded before writing to it?
 
     def needs_upgrade(self):
         """Does this database need to be upgraded before writing to it?
 


@@ -191,13 +218,9 @@ class Database(object):
         etc.) will work unless :meth:`upgrade` is called successfully first.
 
         :returns: `True` or `False`
         etc.) will work unless :meth:`upgrade` is called successfully first.
 
         :returns: `True` or `False`

-        :exception: :exc:`NotmuchError` with STATUS.NOT_INITIALIZED if
-                    the database was not intitialized.

         """
         """

-        # Raise a NotmuchError if not initialized
-        self._verify_initialized_db()
-
-        return nmlib.notmuch_database_needs_upgrade(self._db)
+        self._assert_db_is_initialized()
+        return self._needs_upgrade(self._db)

 
     def upgrade(self):
         """Upgrades the current database
 
     def upgrade(self):
         """Upgrades the current database


@@ -214,13 +237,15 @@ class Database(object):
 
         :TODO: catch exceptions, document return values and etc...
         """
 
         :TODO: catch exceptions, document return values and etc...
         """

-        # Raise a NotmuchError if not initialized
-        self._verify_initialized_db()
-
+        self._assert_db_is_initialized()

         status = Database._upgrade(self._db, None, None)
         #TODO: catch exceptions, document return values and etc
         return status
 
         status = Database._upgrade(self._db, None, None)
         #TODO: catch exceptions, document return values and etc
         return status
 

+    _begin_atomic = nmlib.notmuch_database_begin_atomic
+    _begin_atomic.argtypes = [NotmuchDatabaseP]
+    _begin_atomic.restype = c_uint
+

     def begin_atomic(self):
         """Begin an atomic database operation
 
     def begin_atomic(self):
         """Begin an atomic database operation
 


@@ -230,36 +255,39 @@ class Database(object):
         transaction, this only ensures atomicity, not durability;
         neither begin nor end necessarily flush modifications to disk.
 
         transaction, this only ensures atomicity, not durability;
         neither begin nor end necessarily flush modifications to disk.
 

-        :returns: STATUS.SUCCESS or raises
+        :returns: :attr:`STATUS`.SUCCESS or raises
+        :exception: :exc:`NotmuchError`: :attr:`STATUS`.XAPIAN_EXCEPTION
+                    Xapian exception occurred; atomic section not entered.

 
 

-        :exception: :exc:`NotmuchError` STATUS.XAPIAN_EXCEPTION::
-
-                        A Xapian exception occurred; atomic section not
-                        entered."""
-        # Raise a NotmuchError if not initialized
-        self._verify_initialized_db()
-        status = nmlib.notmuch_database_begin_atomic(self._db)
+        *Added in notmuch 0.9*"""
+        self._assert_db_is_initialized()
+        status = self._begin_atomic(self._db)

         if status != STATUS.SUCCESS:
             raise NotmuchError(status)
         return status
 
         if status != STATUS.SUCCESS:
             raise NotmuchError(status)
         return status
 

+    _end_atomic = nmlib.notmuch_database_end_atomic
+    _end_atomic.argtypes = [NotmuchDatabaseP]
+    _end_atomic.restype = c_uint
+

     def end_atomic(self):
         """Indicate the end of an atomic database operation
 
         See :meth:`begin_atomic` for details.
 
     def end_atomic(self):
         """Indicate the end of an atomic database operation
 
         See :meth:`begin_atomic` for details.
 

-        :returns: STATUS.SUCCESS or raises
+        :returns: :attr:`STATUS`.SUCCESS or raises

 
         :exception:
             :exc:`NotmuchError`:
 
         :exception:
             :exc:`NotmuchError`:

-                STATUS.XAPIAN_EXCEPTION
+                :attr:`STATUS`.XAPIAN_EXCEPTION

                     A Xapian exception occurred; atomic section not
                     ended.
                     A Xapian exception occurred; atomic section not
                     ended.

-                STATUS.UNBALANCED_ATOMIC:
-                    end_atomic has been called more times than begin_atomic."""
-        # Raise a NotmuchError if not initialized
-        self._verify_initialized_db()
-        status = nmlib.notmuch_database_end_atomic(self._db)
+                :attr:`STATUS`.UNBALANCED_ATOMIC:
+                    end_atomic has been called more times than begin_atomic.
+
+        *Added in notmuch 0.9*"""
+        self._assert_db_is_initialized()
+        status = self._end_atomic(self._db)

         if status != STATUS.SUCCESS:
             raise NotmuchError(status)
         return status
         if status != STATUS.SUCCESS:
             raise NotmuchError(status)
         return status


@@ -268,27 +296,22 @@ class Database(object):
         """Returns a :class:`Directory` of path,
         (creating it if it does not exist(?))
 
         """Returns a :class:`Directory` of path,
         (creating it if it does not exist(?))
 

-        .. warning:: This call needs a writeable database in
-           Database.MODE.READ_WRITE mode. The underlying library will exit the
-           program if this method is used on a read-only database!
+        .. warning::
+
+            This call needs a writeable database in
+            :attr:`Database.MODE`.READ_WRITE mode. The underlying library will
+            exit the program if this method is used on a read-only database!

 
         :param path: An unicode string containing the path relative to the path
 
         :param path: An unicode string containing the path relative to the path

-              of database (see :meth:`get_path`), or else should be an absolute path
-              with initial components that match the path of 'database'.
+              of database (see :meth:`get_path`), or else should be an absolute
+              path with initial components that match the path of 'database'.

         :returns: :class:`Directory` or raises an exception.
         :returns: :class:`Directory` or raises an exception.

-        :exception: :exc:`NotmuchError`
-
-                  STATUS.NOT_INITIALIZED
-                    If the database was not intitialized.
-
-                  STATUS.FILE_ERROR
+        :exception:
+            :exc:`NotmuchError` with :attr:`STATUS`.FILE_ERROR

                     If path is not relative database or absolute with initial
                     components same as database.
                     If path is not relative database or absolute with initial
                     components same as database.

-

         """
         """

-        # Raise a NotmuchError if not initialized
-        self._verify_initialized_db()
-
+        self._assert_db_is_initialized()

         # sanity checking if path is valid, and make path absolute
         if path[0] == os.sep:
             # we got an absolute path
         # sanity checking if path is valid, and make path absolute
         if path[0] == os.sep:
             # we got an absolute path


@@ -307,18 +330,24 @@ class Database(object):
         # return the Directory, init it with the absolute path
         return Directory(_str(abs_dirpath), dir_p, self)
 
         # return the Directory, init it with the absolute path
         return Directory(_str(abs_dirpath), dir_p, self)
 

+    _add_message = nmlib.notmuch_database_add_message
+    _add_message.argtypes = [NotmuchDatabaseP, c_char_p,
+                             POINTER(NotmuchMessageP)]
+    _add_message.restype = c_uint
+

     def add_message(self, filename, sync_maildir_flags=False):
         """Adds a new message to the database
 
     def add_message(self, filename, sync_maildir_flags=False):
         """Adds a new message to the database
 

-        :param filename: should be a path relative to the path of the open
-        database (see :meth:`get_path`), or else should be an absolute
-        filename with initial components that match the path of the
-        database.
+        :param filename: should be a path relative to the path of the
+            open database (see :meth:`get_path`), or else should be an
+            absolute filename with initial components that match the
+            path of the database.

 
 

-        The file should be a single mail message (not a multi-message mbox)
-        that is expected to remain at its current location, since the
-        notmuch database will reference the filename, and will not copy the
-        entire contents of the file.
+            The file should be a single mail message (not a
+            multi-message mbox) that is expected to remain at its
+            current location, since the notmuch database will reference
+            the filename, and will not copy the entire contents of the
+            file.

 
         :param sync_maildir_flags: If the message contains Maildir
             flags, we will -depending on the notmuch configuration- sync
 
         :param sync_maildir_flags: If the message contains Maildir
             flags, we will -depending on the notmuch configuration- sync


@@ -331,39 +360,33 @@ class Database(object):
 
            1) a :class:`Message` object that can be used for things
               such as adding tags to the just-added message.
 
            1) a :class:`Message` object that can be used for things
               such as adding tags to the just-added message.

-           2) one of the following STATUS values:
+           2) one of the following :attr:`STATUS` values:

 
 

-              STATUS.SUCCESS
+              :attr:`STATUS`.SUCCESS

                   Message successfully added to database.
                   Message successfully added to database.

-              STATUS.DUPLICATE_MESSAGE_ID
+              :attr:`STATUS`.DUPLICATE_MESSAGE_ID

                   Message has the same message ID as another message already
                   in the database. The new filename was successfully added
                   to the list of the filenames for the existing message.
 
                   Message has the same message ID as another message already
                   in the database. The new filename was successfully added
                   to the list of the filenames for the existing message.
 

-        :rtype:   2-tuple(:class:`Message`, STATUS)
+        :rtype:   2-tuple(:class:`Message`, :attr:`STATUS`)

 
         :exception: Raises a :exc:`NotmuchError` with the following meaning.
               If such an exception occurs, nothing was added to the database.
 
 
         :exception: Raises a :exc:`NotmuchError` with the following meaning.
               If such an exception occurs, nothing was added to the database.
 

-              STATUS.FILE_ERROR
+              :attr:`STATUS`.FILE_ERROR

                       An error occurred trying to open the file, (such as
                       permission denied, or file not found, etc.).
                       An error occurred trying to open the file, (such as
                       permission denied, or file not found, etc.).

-              STATUS.FILE_NOT_EMAIL
+              :attr:`STATUS`.FILE_NOT_EMAIL

                       The contents of filename don't look like an email
                       message.
                       The contents of filename don't look like an email
                       message.

-              STATUS.READ_ONLY_DATABASE
+              :attr:`STATUS`.READ_ONLY_DATABASE

                       Database was opened in read-only mode so no message can
                       be added.
                       Database was opened in read-only mode so no message can
                       be added.

-              STATUS.NOT_INITIALIZED
-                      The database has not been initialized.

         """
         """

-        # Raise a NotmuchError if not initialized
-        self._verify_initialized_db()
-
-        msg_p = c_void_p()
-        status = nmlib.notmuch_database_add_message(self._db,
-                                                  _str(filename),
-                                                  byref(msg_p))
+        self._assert_db_is_initialized()
+        msg_p = NotmuchMessageP()
+        status = self._add_message(self._db, _str(filename), byref(msg_p))

 
         if not status in [STATUS.SUCCESS, STATUS.DUPLICATE_MESSAGE_ID]:
             raise NotmuchError(status)
 
         if not status in [STATUS.SUCCESS, STATUS.DUPLICATE_MESSAGE_ID]:
             raise NotmuchError(status)


@@ -375,6 +398,10 @@ class Database(object):
             msg.maildir_flags_to_tags()
         return (msg, status)
 
             msg.maildir_flags_to_tags()
         return (msg, status)
 

+    _remove_message = nmlib.notmuch_database_remove_message
+    _remove_message.argtypes = [NotmuchDatabaseP, c_char_p]
+    _remove_message.restype = c_uint
+

     def remove_message(self, filename):
         """Removes a message (filename) from the given notmuch database
 
     def remove_message(self, filename):
         """Removes a message (filename) from the given notmuch database
 


@@ -385,12 +412,12 @@ class Database(object):
         is removed for a particular message, the database content for that
         message will be entirely removed.
 
         is removed for a particular message, the database content for that
         message will be entirely removed.
 

-        :returns: A STATUS value with the following meaning:
+        :returns: A :attr:`STATUS` value with the following meaning:

 
 

-             STATUS.SUCCESS
+             :attr:`STATUS`.SUCCESS

                The last filename was removed and the message was removed
                from the database.
                The last filename was removed and the message was removed
                from the database.

-             STATUS.DUPLICATE_MESSAGE_ID
+             :attr:`STATUS`.DUPLICATE_MESSAGE_ID

                This filename was removed but the message persists in the
                database with at least one other filename.
 
                This filename was removed but the message persists in the
                database with at least one other filename.
 


@@ -398,17 +425,12 @@ class Database(object):
              If such an exception occurs, nothing was removed from the
              database.
 
              If such an exception occurs, nothing was removed from the
              database.
 

-             STATUS.READ_ONLY_DATABASE
+             :attr:`STATUS`.READ_ONLY_DATABASE

                Database was opened in read-only mode so no message can be
                removed.
                Database was opened in read-only mode so no message can be
                removed.

-             STATUS.NOT_INITIALIZED
-               The database has not been initialized.

         """
         """

-        # Raise a NotmuchError if not initialized
-        self._verify_initialized_db()
-
-        return nmlib.notmuch_database_remove_message(self._db,
-                                                       filename)
+        self._assert_db_is_initialized()
+        return self._remove_message(self._db, _str(filename))

 
     def find_message(self, msgid):
         """Returns a :class:`Message` as identified by its message ID
 
     def find_message(self, msgid):
         """Returns a :class:`Message` as identified by its message ID


@@ -416,47 +438,70 @@ class Database(object):
         Wraps the underlying *notmuch_database_find_message* function.
 
         :param msgid: The message ID
         Wraps the underlying *notmuch_database_find_message* function.
 
         :param msgid: The message ID

-        :type msgid: string
-        :returns: :class:`Message` or `None` if no message is found or
-                  if any xapian exception or out-of-memory situation
-                  occurs. Do note that Xapian Exceptions include
-                  "Database modified" situations, e.g. when the
-                  notmuch database has been modified by
-                  another program in the meantime. A return value of
-                  `None` is therefore no guarantee that the message
-                  does not exist.
-        :exception: :exc:`NotmuchError` with STATUS.NOT_INITIALIZED if
-                  the database was not intitialized.
+        :type msgid: unicode or str
+        :returns: :class:`Message` or `None` if no message is found.
+        :exception:
+            :exc:`OutOfMemoryError`
+                  If an Out-of-memory occured while constructing the message.
+            :exc:`XapianError`
+                  In case of a Xapian Exception. These exceptions
+                  include "Database modified" situations, e.g. when the
+                  notmuch database has been modified by another program
+                  in the meantime. In this case, you should close and
+                  reopen the database and retry.
+            :exc:`NotInitializedError` if
+                    the database was not intitialized.

         """
         """

-        # Raise a NotmuchError if not initialized
-        self._verify_initialized_db()
-
-        msg_p = Database._find_message(self._db, _str(msgid))
+        self._assert_db_is_initialized()
+        msg_p = NotmuchMessageP()
+        status = Database._find_message(self._db, _str(msgid), byref(msg_p))
+        if status != STATUS.SUCCESS:
+            raise NotmuchError(status)

         return msg_p and Message(msg_p, self) or None
 
     def find_message_by_filename(self, filename):
         """Find a message with the given filename
 
         return msg_p and Message(msg_p, self) or None
 
     def find_message_by_filename(self, filename):
         """Find a message with the given filename
 

+        .. warning::
+
+            This call needs a writeable database in
+            :attr:`Database.MODE`.READ_WRITE mode. The underlying library will
+            exit the program if this method is used on a read-only database!
+

         :returns: If the database contains a message with the given
             filename, then a class:`Message:` is returned.  This
         :returns: If the database contains a message with the given
             filename, then a class:`Message:` is returned.  This

-            function returns None in the following situations:
+            function returns None if no message is found with the given
+            filename.
+
+        :exception:
+            :exc:`OutOfMemoryError`
+                  If an Out-of-memory occured while constructing the message.
+            :exc:`XapianError`
+                  In case of a Xapian Exception. These exceptions
+                  include "Database modified" situations, e.g. when the
+                  notmuch database has been modified by another program
+                  in the meantime. In this case, you should close and
+                  reopen the database and retry.
+            :exc:`NotInitializedError` if
+                    the database was not intitialized.

 
 

-                * No message is found with the given filename
-                * An out-of-memory situation occurs
-                * A Xapian exception occurs"""
-        self._verify_initialized_db()
-        msg_p = Database._find_message_by_filename(self._db, _str(filename))
+        *Added in notmuch 0.9*"""
+        self._assert_db_is_initialized()
+        msg_p = NotmuchMessageP()
+        status = Database._find_message_by_filename(self._db, _str(filename),
+                                                    byref(msg_p))
+        if status != STATUS.SUCCESS:
+            raise NotmuchError(status)

         return msg_p and Message(msg_p, self) or None
 
     def get_all_tags(self):
         """Returns :class:`Tags` with a list of all tags found in the database
 
         :returns: :class:`Tags`
         return msg_p and Message(msg_p, self) or None
 
     def get_all_tags(self):
         """Returns :class:`Tags` with a list of all tags found in the database
 
         :returns: :class:`Tags`

-        :execption: :exc:`NotmuchError` with STATUS.NULL_POINTER on error
+        :execption: :exc:`NotmuchError` with :attr:`STATUS`.NULL_POINTER
+                    on error

         """
         """

-        # Raise a NotmuchError if not initialized
-        self._verify_initialized_db()
-
+        self._assert_db_is_initialized()

         tags_p = Database._get_all_tags(self._db)
         if tags_p == None:
             raise NotmuchError(STATUS.NULL_POINTER)
         tags_p = Database._get_all_tags(self._db)
         if tags_p == None:
             raise NotmuchError(STATUS.NULL_POINTER)


@@ -480,24 +525,31 @@ class Database(object):
 
         This function is a python extension and not in the underlying C API.
         """
 
         This function is a python extension and not in the underlying C API.
         """

-        # Raise a NotmuchError if not initialized
-        self._verify_initialized_db()
-

         return Query(self, querystring)
 
     def __repr__(self):
         return "'Notmuch DB " + self.get_path() + "'"
 
         return Query(self, querystring)
 
     def __repr__(self):
         return "'Notmuch DB " + self.get_path() + "'"
 

+    _close = nmlib.notmuch_database_close
+    _close.argtypes = [NotmuchDatabaseP]
+    _close.restype = None
+

     def __del__(self):
         """Close and free the notmuch database if needed"""
         if self._db is not None:
     def __del__(self):
         """Close and free the notmuch database if needed"""
         if self._db is not None:

-            nmlib.notmuch_database_close(self._db)
+            self._close(self._db)

 
     def _get_user_default_db(self):
         """ Reads a user's notmuch config and returns his db location
 
         Throws a NotmuchError if it cannot find it"""
 
     def _get_user_default_db(self):
         """ Reads a user's notmuch config and returns his db location
 
         Throws a NotmuchError if it cannot find it"""

-        from ConfigParser import SafeConfigParser
+        try:
+            # python3.x
+            from configparser import SafeConfigParser
+        except ImportError:
+            # python2.x
+            from ConfigParser import SafeConfigParser
+

         config = SafeConfigParser()
         conf_f = os.getenv('NOTMUCH_CONFIG',
                            os.path.expanduser('~/.notmuch-config'))
         config = SafeConfigParser()
         conf_f = os.getenv('NOTMUCH_CONFIG',
                            os.path.expanduser('~/.notmuch-config'))


@@ -523,11 +575,12 @@ class Query(object):
     A query selects and filters a subset of messages from the notmuch
     database we derive from.
 
     A query selects and filters a subset of messages from the notmuch
     database we derive from.
 

-    Query() provides an instance attribute :attr:`sort`, which
+    :class:`Query` provides an instance attribute :attr:`sort`, which

     contains the sort order (if specified via :meth:`set_sort`) or
     `None`.
 
     contains the sort order (if specified via :meth:`set_sort`) or
     `None`.
 

-    Technically, it wraps the underlying *notmuch_query_t* struct.
+    Any function in this class may throw an :exc:`NotInitializedError`
+    in case the underlying query object was not set up correctly.

 
     .. note:: Do remember that as soon as we tear down this object,
            all underlying derived objects such as threads,
 
     .. note:: Do remember that as soon as we tear down this object,
            all underlying derived objects such as threads,


@@ -541,18 +594,22 @@ class Query(object):
 
     """notmuch_query_create"""
     _create = nmlib.notmuch_query_create
 
     """notmuch_query_create"""
     _create = nmlib.notmuch_query_create

-    _create.restype = c_void_p
+    _create.argtypes = [NotmuchDatabaseP, c_char_p]
+    _create.restype = NotmuchQueryP

 
     """notmuch_query_search_threads"""
     _search_threads = nmlib.notmuch_query_search_threads
 
     """notmuch_query_search_threads"""
     _search_threads = nmlib.notmuch_query_search_threads

-    _search_threads.restype = c_void_p
+    _search_threads.argtypes = [NotmuchQueryP]
+    _search_threads.restype = NotmuchThreadsP

 
     """notmuch_query_search_messages"""
     _search_messages = nmlib.notmuch_query_search_messages
 
     """notmuch_query_search_messages"""
     _search_messages = nmlib.notmuch_query_search_messages

-    _search_messages.restype = c_void_p
+    _search_messages.argtypes = [NotmuchQueryP]
+    _search_messages.restype = NotmuchMessagesP

 
     """notmuch_query_count_messages"""
     _count_messages = nmlib.notmuch_query_count_messages
 
     """notmuch_query_count_messages"""
     _count_messages = nmlib.notmuch_query_count_messages

+    _count_messages.argtypes = [NotmuchQueryP]

     _count_messages.restype = c_uint
 
     def __init__(self, db, querystr):
     _count_messages.restype = c_uint
 
     def __init__(self, db, querystr):


@@ -567,6 +624,11 @@ class Query(object):
         self.sort = None
         self.create(db, querystr)
 
         self.sort = None
         self.create(db, querystr)
 

+    def _assert_query_is_initialized(self):
+        """Raises :exc:`NotInitializedError` if self._query is `None`"""
+        if self._query is None:
+            raise NotInitializedError()
+

     def create(self, db, querystr):
         """Creates a new query derived from a Database
 
     def create(self, db, querystr):
         """Creates a new query derived from a Database
 


@@ -578,37 +640,33 @@ class Query(object):
         :param querystr: The query string
         :type querystr: utf-8 encoded str or unicode
         :returns: Nothing
         :param querystr: The query string
         :type querystr: utf-8 encoded str or unicode
         :returns: Nothing

-        :exception: :exc:`NotmuchError`
-
-                      * STATUS.NOT_INITIALIZED if db is not inited
-                      * STATUS.NULL_POINTER if the query creation failed
-                        (too little memory)
+        :exception:
+            :exc:`NullPointerError` if the query creation failed
+                (e.g. too little memory).
+            :exc:`NotInitializedError` if the underlying db was not
+                intitialized.

         """
         """

-        if db.db_p is None:
-            raise NotmuchError(STATUS.NOT_INITIALIZED)
+        db._assert_db_is_initialized()

         # create reference to parent db to keep it alive
         self._db = db
         # create query, return None if too little mem available
         query_p = Query._create(db.db_p, _str(querystr))
         # create reference to parent db to keep it alive
         self._db = db
         # create query, return None if too little mem available
         query_p = Query._create(db.db_p, _str(querystr))

-        if query_p is None:
-            NotmuchError(STATUS.NULL_POINTER)
+        if not query_p:
+            raise NullPointerError

         self._query = query_p
 
         self._query = query_p
 

+    _set_sort = nmlib.notmuch_query_set_sort
+    _set_sort.argtypes = [NotmuchQueryP, c_uint]
+    _set_sort.argtypes = None
+

     def set_sort(self, sort):
         """Set the sort order future results will be delivered in
 
     def set_sort(self, sort):
         """Set the sort order future results will be delivered in
 

-        Wraps the underlying *notmuch_query_set_sort* function.
-

         :param sort: Sort order (see :attr:`Query.SORT`)
         :param sort: Sort order (see :attr:`Query.SORT`)

-        :returns: Nothing
-        :exception: :exc:`NotmuchError` STATUS.NOT_INITIALIZED if query has not
-                    been initialized.

         """
         """

-        if self._query is None:
-            raise NotmuchError(STATUS.NOT_INITIALIZED)
-
+        self._assert_query_is_initialized()

         self.sort = sort
         self.sort = sort

-        nmlib.notmuch_query_set_sort(self._query, sort)
+        self._set_sort(self._query, sort)

 
     def search_threads(self):
         """Execute a query for threads
 
     def search_threads(self):
         """Execute a query for threads


@@ -621,46 +679,28 @@ class Query(object):
         match the query. The method :meth:`Message.get_flag` allows us
         to get the value of this flag.
 
         match the query. The method :meth:`Message.get_flag` allows us
         to get the value of this flag.
 

-        Technically, it wraps the underlying
-        *notmuch_query_search_threads* function.
-

         :returns: :class:`Threads`
         :returns: :class:`Threads`

-        :exception: :exc:`NotmuchError`
-
-                      * STATUS.NOT_INITIALIZED if query is not inited
-                      * STATUS.NULL_POINTER if search_threads failed
+        :exception: :exc:`NullPointerError` if search_threads failed

         """
         """

-        if self._query is None:
-            raise NotmuchError(STATUS.NOT_INITIALIZED)
-
+        self._assert_query_is_initialized()

         threads_p = Query._search_threads(self._query)
 
         threads_p = Query._search_threads(self._query)
 

-        if threads_p is None:
-            raise NotmuchError(STATUS.NULL_POINTER)
-
+        if not threads_p:
+            raise NullPointerError

         return Threads(threads_p, self)
 
     def search_messages(self):
         """Filter messages according to the query and return
         :class:`Messages` in the defined sort order
 
         return Threads(threads_p, self)
 
     def search_messages(self):
         """Filter messages according to the query and return
         :class:`Messages` in the defined sort order
 

-        Technically, it wraps the underlying
-        *notmuch_query_search_messages* function.
-

         :returns: :class:`Messages`
         :returns: :class:`Messages`

-        :exception: :exc:`NotmuchError`
-
-                      * STATUS.NOT_INITIALIZED if query is not inited
-                      * STATUS.NULL_POINTER if search_messages failed
+        :exception: :exc:`NullPointerError` if search_messages failed

         """
         """

-        if self._query is None:
-            raise NotmuchError(STATUS.NOT_INITIALIZED)
-
+        self._assert_query_is_initialized()

         msgs_p = Query._search_messages(self._query)
 
         msgs_p = Query._search_messages(self._query)
 

-        if msgs_p is None:
-            NotmuchError(STATUS.NULL_POINTER)
-
+        if not msgs_p:
+            raise NullPointerError

         return Messages(msgs_p, self)
 
     def count_messages(self):
         return Messages(msgs_p, self)
 
     def count_messages(self):


@@ -674,19 +714,18 @@ class Query(object):
         *notmuch_query_count_messages* function.
 
         :returns: :class:`Messages`
         *notmuch_query_count_messages* function.
 
         :returns: :class:`Messages`

-        :exception: :exc:`NotmuchError`
-
-                      * STATUS.NOT_INITIALIZED if query is not inited

         """
         """

-        if self._query is None:
-            raise NotmuchError(STATUS.NOT_INITIALIZED)
-
+        self._assert_query_is_initialized()

         return Query._count_messages(self._query)
 
         return Query._count_messages(self._query)
 

+    _destroy = nmlib.notmuch_query_destroy
+    _destroy.argtypes = [NotmuchQueryP]
+    _destroy.restype = None
+

     def __del__(self):
         """Close and free the Query"""
         if self._query is not None:
     def __del__(self):
         """Close and free the Query"""
         if self._query is not None:

-            nmlib.notmuch_query_destroy(self._query)
+            self._destroy(self._query)

 
 
 class Directory(object):
 
 
 class Directory(object):


@@ -705,23 +744,28 @@ class Directory(object):
 
     """notmuch_directory_get_mtime"""
     _get_mtime = nmlib.notmuch_directory_get_mtime
 
     """notmuch_directory_get_mtime"""
     _get_mtime = nmlib.notmuch_directory_get_mtime

+    _get_mtime.argtypes = [NotmuchDirectoryP]

     _get_mtime.restype = c_long
 
     """notmuch_directory_set_mtime"""
     _set_mtime = nmlib.notmuch_directory_set_mtime
     _get_mtime.restype = c_long
 
     """notmuch_directory_set_mtime"""
     _set_mtime = nmlib.notmuch_directory_set_mtime

-    _set_mtime.argtypes = [c_char_p, c_long]
+    _set_mtime.argtypes = [NotmuchDirectoryP, c_long]
+    _set_mtime.restype = c_uint

 
     """notmuch_directory_get_child_files"""
     _get_child_files = nmlib.notmuch_directory_get_child_files
 
     """notmuch_directory_get_child_files"""
     _get_child_files = nmlib.notmuch_directory_get_child_files

-    _get_child_files.restype = c_void_p
+    _get_child_files.argtypes = [NotmuchDirectoryP]
+    _get_child_files.restype = NotmuchFilenamesP

 
     """notmuch_directory_get_child_directories"""
     _get_child_directories = nmlib.notmuch_directory_get_child_directories
 
     """notmuch_directory_get_child_directories"""
     _get_child_directories = nmlib.notmuch_directory_get_child_directories

-    _get_child_directories.restype = c_void_p
+    _get_child_directories.argtypes = [NotmuchDirectoryP]
+    _get_child_directories.restype = NotmuchFilenamesP

 
 

-    def _verify_dir_initialized(self):
-        """Raises a NotmuchError(STATUS.NOT_INITIALIZED) if dir_p is None"""
-        if self._dir_p is None:
+    def _assert_dir_is_initialized(self):
+        """Raises a NotmuchError(:attr:`STATUS`.NOT_INITIALIZED)
+        if dir_p is None"""
+        if not self._dir_p:

             raise NotmuchError(STATUS.NOT_INITIALIZED)
 
     def __init__(self, path, dir_p, parent):
             raise NotmuchError(STATUS.NOT_INITIALIZED)
 
     def __init__(self, path, dir_p, parent):


@@ -757,26 +801,26 @@ class Directory(object):
           and know that it only needs to add files if the mtime of the
           directory and files are newer than the stored timestamp.
 
           and know that it only needs to add files if the mtime of the
           directory and files are newer than the stored timestamp.
 

-          .. note:: :meth:`get_mtime` function does not allow the caller
-                 to distinguish a timestamp of 0 from a non-existent
-                 timestamp. So don't store a timestamp of 0 unless you are
-                 comfortable with that.
+          .. note::
+
+                :meth:`get_mtime` function does not allow the caller to
+                distinguish a timestamp of 0 from a non-existent timestamp. So
+                don't store a timestamp of 0 unless you are comfortable with
+                that.

 
           :param mtime: A (time_t) timestamp
           :returns: Nothing on success, raising an exception on failure.
           :exception: :exc:`NotmuchError`:
 
 
           :param mtime: A (time_t) timestamp
           :returns: Nothing on success, raising an exception on failure.
           :exception: :exc:`NotmuchError`:
 

-                        STATUS.XAPIAN_EXCEPTION
+                        :attr:`STATUS`.XAPIAN_EXCEPTION

                           A Xapian exception occurred, mtime not stored.
                           A Xapian exception occurred, mtime not stored.

-                        STATUS.READ_ONLY_DATABASE
+                        :attr:`STATUS`.READ_ONLY_DATABASE

                           Database was opened in read-only mode so directory
                           mtime cannot be modified.
                           Database was opened in read-only mode so directory
                           mtime cannot be modified.

-                        STATUS.NOT_INITIALIZED
+                        :attr:`STATUS`.NOT_INITIALIZED

                           The directory has not been initialized
         """
                           The directory has not been initialized
         """

-        #Raise a NotmuchError(STATUS.NOT_INITIALIZED) if the dir_p is None
-        self._verify_dir_initialized()
-
+        self._assert_dir_is_initialized()

         #TODO: make sure, we convert the mtime parameter to a 'c_long'
         status = Directory._set_mtime(self._dir_p, mtime)
 
         #TODO: make sure, we convert the mtime parameter to a 'c_long'
         status = Directory._set_mtime(self._dir_p, mtime)
 


@@ -795,12 +839,10 @@ class Directory(object):
         :returns: Nothing on success, raising an exception on failure.
         :exception: :exc:`NotmuchError`:
 
         :returns: Nothing on success, raising an exception on failure.
         :exception: :exc:`NotmuchError`:
 

-                        STATUS.NOT_INITIALIZED
+                        :attr:`STATUS`.NOT_INITIALIZED

                           The directory has not been initialized
         """
                           The directory has not been initialized
         """

-        #Raise a NotmuchError(STATUS.NOT_INITIALIZED) if self.dir_p is None
-        self._verify_dir_initialized()
-
+        self._assert_dir_is_initialized()

         return Directory._get_mtime(self._dir_p)
 
     # Make mtime attribute a property of Directory()
         return Directory._get_mtime(self._dir_p)
 
     # Make mtime attribute a property of Directory()


@@ -817,9 +859,7 @@ class Directory(object):
         The returned filenames will be the basename-entries only (not
         complete paths.
         """
         The returned filenames will be the basename-entries only (not
         complete paths.
         """

-        #Raise a NotmuchError(STATUS.NOT_INITIALIZED) if self._dir_p is None
-        self._verify_dir_initialized()
-
+        self._assert_dir_is_initialized()

         files_p = Directory._get_child_files(self._dir_p)
         return Filenames(files_p, self)
 
         files_p = Directory._get_child_files(self._dir_p)
         return Filenames(files_p, self)
 


@@ -830,9 +870,7 @@ class Directory(object):
         The returned filenames will be the basename-entries only (not
         complete paths.
         """
         The returned filenames will be the basename-entries only (not
         complete paths.
         """

-        #Raise a NotmuchError(STATUS.NOT_INITIALIZED) if self._dir_p is None
-        self._verify_dir_initialized()
-
+        self._assert_dir_is_initialized()

         files_p = Directory._get_child_directories(self._dir_p)
         return Filenames(files_p, self)
 
         files_p = Directory._get_child_directories(self._dir_p)
         return Filenames(files_p, self)
 


@@ -845,10 +883,14 @@ class Directory(object):
         """Object representation"""
         return "<notmuch Directory object '%s'>" % self._path
 
         """Object representation"""
         return "<notmuch Directory object '%s'>" % self._path
 

+    _destroy = nmlib.notmuch_directory_destroy
+    _destroy.argtypes = [NotmuchDirectoryP]
+    _destroy.argtypes = None
+

     def __del__(self):
         """Close and free the Directory"""
         if self._dir_p is not None:
     def __del__(self):
         """Close and free the Directory"""
         if self._dir_p is not None:

-            nmlib.notmuch_directory_destroy(self._dir_p)
+            self._destroy(self._dir_p)

 
 
 class Filenames(object):
 
 
 class Filenames(object):


@@ -856,6 +898,7 @@ class Filenames(object):
 
     #notmuch_filenames_get
     _get = nmlib.notmuch_filenames_get
 
     #notmuch_filenames_get
     _get = nmlib.notmuch_filenames_get

+    _get.argtypes = [NotmuchFilenamesP]

     _get.restype = c_char_p
 
     def __init__(self, files_p, parent):
     _get.restype = c_char_p
 
     def __init__(self, files_p, parent):


@@ -874,41 +917,57 @@ class Filenames(object):
         """ Make Filenames an iterator """
         return self
 
         """ Make Filenames an iterator """
         return self
 

-    def next(self):
-        if self._files_p is None:
+    _valid = nmlib.notmuch_filenames_valid
+    _valid.argtypes = [NotmuchFilenamesP]
+    _valid.restype = bool
+
+    _move_to_next = nmlib.notmuch_filenames_move_to_next
+    _move_to_next.argtypes = [NotmuchFilenamesP]
+    _move_to_next.restype = None
+
+    def __next__(self):
+        if not self._files_p:

             raise NotmuchError(STATUS.NOT_INITIALIZED)
 
             raise NotmuchError(STATUS.NOT_INITIALIZED)
 

-        if not nmlib.notmuch_filenames_valid(self._files_p):
+        if not self._valid(self._files_p):

             self._files_p = None
             raise StopIteration
 
             self._files_p = None
             raise StopIteration
 

-        file = Filenames._get(self._files_p)
-        nmlib.notmuch_filenames_move_to_next(self._files_p)
-        return file
+        file_ = Filenames._get(self._files_p)
+        self._move_to_next(self._files_p)
+        return file_.decode('utf-8', 'ignore')
+    next = __next__ # python2.x iterator protocol compatibility

 
     def __len__(self):
         """len(:class:`Filenames`) returns the number of contained files
 
 
     def __len__(self):
         """len(:class:`Filenames`) returns the number of contained files
 

-        .. note:: As this iterates over the files, we will not be able to
-               iterate over them again! So this will fail::
+        .. note::
+
+            As this iterates over the files, we will not be able to
+            iterate over them again! So this will fail::

 
                  #THIS FAILS
                  files = Database().get_directory('').get_child_files()
 
                  #THIS FAILS
                  files = Database().get_directory('').get_child_files()

-                 if len(files) > 0:              #this 'exhausts' msgs
-                     # next line raises NotmuchError(STATUS.NOT_INITIALIZED)!!!
+                 if len(files) > 0:  # this 'exhausts' msgs
+                     # next line raises
+                     # NotmuchError(:attr:`STATUS`.NOT_INITIALIZED)

                      for file in files: print file
         """
                      for file in files: print file
         """

-        if self._files_p is None:
+        if not self._files_p:

             raise NotmuchError(STATUS.NOT_INITIALIZED)
 
         i = 0
             raise NotmuchError(STATUS.NOT_INITIALIZED)
 
         i = 0

-        while nmlib.notmuch_filenames_valid(self._files_p):
-            nmlib.notmuch_filenames_move_to_next(self._files_p)
+        while self._valid(self._files_p):
+            self._move_to_next(self._files_p)

             i += 1
         self._files_p = None
         return i
 
             i += 1
         self._files_p = None
         return i
 

+    _destroy = nmlib.notmuch_filenames_destroy
+    _destroy.argtypes = [NotmuchFilenamesP]
+    _destroy.restype = None
+

     def __del__(self):
         """Close and free Filenames"""
         if self._files_p is not None:
     def __del__(self):
         """Close and free Filenames"""
         if self._files_p is not None:

-            nmlib.notmuch_filenames_destroy(self._files_p)
+            self._destroy(self._files_p)