summaryrefslogtreecommitdiffstats
path: root/Doc/c-api/codec.rst
blob: 83252afbb7f78c8e29ff0a64fb83f0cfbe51d097 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
.. _codec-registry:

Codec registry and support functions
====================================

.. c:function:: int PyCodec_Register(PyObject *search_function)

   Register a new codec search function.

   As side effect, this tries to load the :mod:`encodings` package, if not yet
   done, to make sure that it is always first in the list of search functions.

.. c:function:: int PyCodec_KnownEncoding(const char *encoding)

   Return ``1`` or ``0`` depending on whether there is a registered codec for
   the given *encoding*.

.. c:function:: PyObject* PyCodec_Encode(PyObject *object, const char *encoding, const char *errors)

   Generic codec based encoding API.

   *object* is passed through the encoder function found for the given
   *encoding* using the error handling method defined by *errors*.  *errors* may
   be *NULL* to use the default method defined for the codec.  Raises a
   :exc:`LookupError` if no encoder can be found.

.. c:function:: PyObject* PyCodec_Decode(PyObject *object, const char *encoding, const char *errors)

   Generic codec based decoding API.

   *object* is passed through the decoder function found for the given
   *encoding* using the error handling method defined by *errors*.  *errors* may
   be *NULL* to use the default method defined for the codec.  Raises a
   :exc:`LookupError` if no encoder can be found.


Codec lookup API
----------------

In the following functions, the *encoding* string is looked up converted to all
lower-case characters, which makes encodings looked up through this mechanism
effectively case-insensitive.  If no codec is found, a :exc:`KeyError` is set
and *NULL* returned.

.. c:function:: PyObject* PyCodec_Encoder(const char *encoding)

   Get an encoder function for the given *encoding*.

.. c:function:: PyObject* PyCodec_Decoder(const char *encoding)

   Get a decoder function for the given *encoding*.

.. c:function:: PyObject* PyCodec_IncrementalEncoder(const char *encoding, const char *errors)

   Get an :class:`~codecs.IncrementalEncoder` object for the given *encoding*.

.. c:function:: PyObject* PyCodec_IncrementalDecoder(const char *encoding, const char *errors)

   Get an :class:`~codecs.IncrementalDecoder` object for the given *encoding*.

.. c:function:: PyObject* PyCodec_StreamReader(const char *encoding, PyObject *stream, const char *errors)

   Get a :class:`~codecs.StreamReader` factory function for the given *encoding*.

.. c:function:: PyObject* PyCodec_StreamWriter(const char *encoding, PyObject *stream, const char *errors)

   Get a :class:`~codecs.StreamWriter` factory function for the given *encoding*.


Registry API for Unicode encoding error handlers
------------------------------------------------

.. c:function:: int PyCodec_RegisterError(const char *name, PyObject *error)

   Register the error handling callback function *error* under the given *name*.
   This callback function will be called by a codec when it encounters
   unencodable characters/undecodable bytes and *name* is specified as the error
   parameter in the call to the encode/decode function.

   The callback gets a single argument, an instance of
   :exc:`UnicodeEncodeError`, :exc:`UnicodeDecodeError` or
   :exc:`UnicodeTranslateError` that holds information about the problematic
   sequence of characters or bytes and their offset in the original string (see
   :ref:`unicodeexceptions` for functions to extract this information).  The
   callback must either raise the given exception, or return a two-item tuple
   containing the replacement for the problematic sequence, and an integer
   giving the offset in the original string at which encoding/decoding should be
   resumed.

   Return ``0`` on success, ``-1`` on error.

.. c:function:: PyObject* PyCodec_LookupError(const char *name)

   Lookup the error handling callback function registered under *name*.  As a
   special case *NULL* can be passed, in which case the error handling callback
   for "strict" will be returned.

.. c:function:: PyObject* PyCodec_StrictErrors(PyObject *exc)

   Raise *exc* as an exception.

.. c:function:: PyObject* PyCodec_IgnoreErrors(PyObject *exc)

   Ignore the unicode error, skipping the faulty input.

.. c:function:: PyObject* PyCodec_ReplaceErrors(PyObject *exc)

   Replace the unicode encode error with ``?`` or ``U+FFFD``.

.. c:function:: PyObject* PyCodec_XMLCharRefReplaceErrors(PyObject *exc)

   Replace the unicode encode error with XML character references.

.. c:function:: PyObject* PyCodec_BackslashReplaceErrors(PyObject *exc)

   Replace the unicode encode error with backslash escapes (``\x``, ``\u`` and
   ``\U``).