]> git.notmuchmail.org Git - notmuch/blobdiff - bindings/python/notmuch/database.py
python: annotate all calls into libnotmuch with types
[notmuch] / bindings / python / notmuch / database.py
index f1c1eb757cc8cc8026381f8fa93a18a7240ceeb5..25b4b1b1ca33a3202f9f8042ff2cad05d8412823 100644 (file)
@@ -18,20 +18,37 @@ Copyright 2010 Sebastian Spaeth <Sebastian@SSpaeth.de>'
 """
 
 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_int, c_char_p, c_void_p, c_uint, c_long, byref, POINTER
+from notmuch.globals import (nmlib, STATUS, NotmuchError, NotInitializedError,
+     NullPointerError, OutOfMemoryError, XapianError, 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
 
 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.
+    """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"""
@@ -41,39 +58,48 @@ class Database(object):
 
     """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
+    _get_path.argtypes = [NotmuchDatabaseP]
     _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
-    _open.restype = c_void_p
+    _open.argtypes = [c_char_p, c_uint]
+    _open.restype = NotmuchDatabaseP
 
     """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
-    _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
-    _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
-    _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
-    _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
@@ -93,8 +119,8 @@ 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`
-        :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:
@@ -110,9 +136,9 @@ class Database(object):
             self.create(path)
 
     def _assert_db_is_initialized(self):
-        """Raises a NotmuchError in case self._db is still None"""
+        """Raises :exc:`NotInitializedError` 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
@@ -128,7 +154,7 @@ class Database(object):
         :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() "
@@ -152,7 +178,7 @@ class Database(object):
         :type status:  :attr:`MODE`
         :returns: Nothing
         :exception: Raises :exc:`NotmuchError` in case
-                    of any failure (after printing an error message on stderr).
+            of any failure (possibly after printing an error message on stderr).
         """
         res = Database._open(_str(path), mode)
 
@@ -161,9 +187,7 @@ class Database(object):
         self._db = res
 
     def get_path(self):
-        """Returns the file path of an open database
-
-        .. ..:: Wraps underlying `notmuch_database_get_path`"""
+        """Returns the file path of an open database"""
         self._assert_db_is_initialized()
         return Database._get_path(self._db).decode('utf-8')
 
@@ -171,12 +195,14 @@ class Database(object):
         """Returns the database format version
 
         :returns: The database version as positive integer
-        :exception: :exc:`NotmuchError` with :attr:`STATUS`.NOT_INITIALIZED if
-                    the database was not intitialized.
         """
         self._assert_db_is_initialized()
         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?
 
@@ -186,11 +212,9 @@ class Database(object):
         etc.) will work unless :meth:`upgrade` is called successfully first.
 
         :returns: `True` or `False`
-        :exception: :exc:`NotmuchError` with :attr:`STATUS`.NOT_INITIALIZED if
-                    the database was not intitialized.
         """
         self._assert_db_is_initialized()
-        return nmlib.notmuch_database_needs_upgrade(self._db)
+        return self._needs_upgrade(self._db)
 
     def upgrade(self):
         """Upgrades the current database
@@ -212,6 +236,10 @@ class Database(object):
         #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
 
@@ -229,11 +257,15 @@ class Database(object):
 
         *Added in notmuch 0.9*"""
         self._assert_db_is_initialized()
-        status = nmlib.notmuch_database_begin_atomic(self._db)
+        status = self._begin_atomic(self._db)
         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
 
@@ -251,7 +283,7 @@ class Database(object):
 
         *Added in notmuch 0.9*"""
         self._assert_db_is_initialized()
-        status = nmlib.notmuch_database_end_atomic(self._db)
+        status = self._end_atomic(self._db)
         if status != STATUS.SUCCESS:
             raise NotmuchError(status)
         return status
@@ -268,15 +300,10 @@ class Database(object):
               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.
-        :exception: :exc:`NotmuchError`
-
-                  :attr:`STATUS`.NOT_INITIALIZED
-                    If the database was not intitialized.
-
-                  :attr:`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.
-
         """
         self._assert_db_is_initialized()
         # sanity checking if path is valid, and make path absolute
@@ -297,6 +324,10 @@ class Database(object):
         # 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
 
@@ -345,14 +376,10 @@ class Database(object):
               :attr:`STATUS`.READ_ONLY_DATABASE
                       Database was opened in read-only mode so no message can
                       be added.
-              :attr:`STATUS`.NOT_INITIALIZED
-                      The database has not been initialized.
         """
         self._assert_db_is_initialized()
         msg_p = c_void_p()
-        status = nmlib.notmuch_database_add_message(self._db,
-                                                  _str(filename),
-                                                  byref(msg_p))
+        status = self._add_message(self._db, _str(filename), byref(msg_p))
 
         if not status in [STATUS.SUCCESS, STATUS.DUPLICATE_MESSAGE_ID]:
             raise NotmuchError(status)
@@ -364,6 +391,10 @@ class Database(object):
             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
 
@@ -390,12 +421,9 @@ class Database(object):
              :attr:`STATUS`.READ_ONLY_DATABASE
                Database was opened in read-only mode so no message can be
                removed.
-             :attr:`STATUS`.NOT_INITIALIZED
-               The database has not been initialized.
         """
         self._assert_db_is_initialized()
-        return nmlib.notmuch_database_remove_message(self._db,
-                                                       filename)
+        return self._remove_message(self._db, filename)
 
     def find_message(self, msgid):
         """Returns a :class:`Message` as identified by its message ID
@@ -403,20 +431,25 @@ class Database(object):
         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 :attr:`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.
         """
         self._assert_db_is_initialized()
-        msg_p = Database._find_message(self._db, _str(msgid))
+        msg_p = c_void_p()
+        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):
@@ -429,15 +462,28 @@ class Database(object):
 
         :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.
 
-                * No message is found with the given filename
-                * An out-of-memory situation occurs
-                * A Xapian exception occurs
+        :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.
 
         *Added in notmuch 0.9*"""
         self._assert_db_is_initialized()
-        msg_p = Database._find_message_by_filename(self._db, _str(filename))
+        msg_p = c_void_p()
+        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):
@@ -470,16 +516,19 @@ class Database(object):
 
         This function is a python extension and not in the underlying C API.
         """
-        self._assert_db_is_initialized()
         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:
-            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
@@ -511,11 +560,12 @@ class Query(object):
     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`.
 
-    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,
@@ -529,18 +579,22 @@ class Query(object):
 
     """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
-    _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
-    _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
+    _count_messages.argtypes = [NotmuchQueryP]
     _count_messages.restype = c_uint
 
     def __init__(self, db, querystr):
@@ -555,6 +609,11 @@ class Query(object):
         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
 
@@ -566,37 +625,33 @@ class Query(object):
         :param querystr: The query string
         :type querystr: utf-8 encoded str or unicode
         :returns: Nothing
-        :exception: :exc:`NotmuchError`
-
-                      * :attr:`STATUS`.NOT_INITIALIZED if db is not inited
-                      * :attr:`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))
         if query_p is None:
-            raise NotmuchError(STATUS.NULL_POINTER)
+            raise NullPointerError
         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
 
-        Wraps the underlying *notmuch_query_set_sort* function.
-
         :param sort: Sort order (see :attr:`Query.SORT`)
-        :returns: Nothing
-        :exception: :exc:`NotmuchError` :attr:`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
-        nmlib.notmuch_query_set_sort(self._query, sort)
+        self._set_sort(self._query, sort)
 
     def search_threads(self):
         """Execute a query for threads
@@ -609,46 +664,28 @@ class Query(object):
         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`
-        :exception: :exc:`NotmuchError`
-
-                      * :attr:`STATUS`.NOT_INITIALIZED if query is not inited
-                      * :attr:`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)
 
         if threads_p is None:
-            raise NotmuchError(STATUS.NULL_POINTER)
-
+            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
 
-        Technically, it wraps the underlying
-        *notmuch_query_search_messages* function.
-
         :returns: :class:`Messages`
-        :exception: :exc:`NotmuchError`
-
-                      * :attr:`STATUS`.NOT_INITIALIZED if query is not inited
-                      * :attr:`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)
 
         if msgs_p is None:
-            raise NotmuchError(STATUS.NULL_POINTER)
-
+            raise NullPointerError
         return Messages(msgs_p, self)
 
     def count_messages(self):
@@ -662,19 +699,18 @@ class Query(object):
         *notmuch_query_count_messages* function.
 
         :returns: :class:`Messages`
-        :exception: :exc:`NotmuchError`
-
-                      * :attr:`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)
 
+    _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:
-            nmlib.notmuch_query_destroy(self._query)
+            self._destroy(self._query)
 
 
 class Directory(object):
@@ -693,19 +729,23 @@ class Directory(object):
 
     """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
-    _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
-    _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
-    _get_child_directories.restype = c_void_p
+    _get_child_directories.argtypes = [NotmuchDirectoryP]
+    _get_child_directories.restype = NotmuchFilenamesP
 
     def _assert_dir_is_initialized(self):
         """Raises a NotmuchError(:attr:`STATUS`.NOT_INITIALIZED) if dir_p is None"""
@@ -825,10 +865,14 @@ class Directory(object):
         """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:
-            nmlib.notmuch_directory_destroy(self._dir_p)
+            self._destroy(self._dir_p)
 
 
 class Filenames(object):
@@ -836,6 +880,7 @@ class Filenames(object):
 
     #notmuch_filenames_get
     _get = nmlib.notmuch_filenames_get
+    _get.argtypes = [NotmuchFilenamesP]
     _get.restype = c_char_p
 
     def __init__(self, files_p, parent):
@@ -854,16 +899,24 @@ class Filenames(object):
         """ Make Filenames an iterator """
         return self
 
+    _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 self._files_p is None:
             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
 
         file = Filenames._get(self._files_p)
-        nmlib.notmuch_filenames_move_to_next(self._files_p)
+        self._move_to_next(self._files_p)
         return file
 
     def __len__(self):
@@ -882,13 +935,17 @@ class Filenames(object):
             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
 
+    _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:
-            nmlib.notmuch_filenames_destroy(self._files_p)
+            self._destroy(self._files_p)