summaryrefslogtreecommitdiffstats
path: root/src/3rdparty/webkit/JavaScriptCore/API/JSStringRef.h
blob: c58b95821043474094fcc4fe7e9a1047b259d262 (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
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
/*
 * Copyright (C) 2006 Apple Computer, Inc.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
 */

#ifndef JSStringRef_h
#define JSStringRef_h

#include <JavaScriptCore/JSValueRef.h>

#ifndef __cplusplus
#include <stdbool.h>
#endif
#include <stddef.h> /* for size_t */

#ifdef __cplusplus
extern "C" {
#endif

#if !defined(WIN32) && !defined(_WIN32) && !defined(__WINSCW__)
/*!
@typedef JSChar
@abstract A Unicode character.
*/
    typedef unsigned short JSChar;
#else
    typedef wchar_t JSChar;
#endif

/*!
@function
@abstract         Creates a JavaScript string from a buffer of Unicode characters.
@param chars      The buffer of Unicode characters to copy into the new JSString.
@param numChars   The number of characters to copy from the buffer pointed to by chars.
@result           A JSString containing chars. Ownership follows the Create Rule.
*/
JS_EXPORT JSStringRef JSStringCreateWithCharacters(const JSChar* chars, size_t numChars);
/*!
@function
@abstract         Creates a JavaScript string from a null-terminated UTF8 string.
@param string     The null-terminated UTF8 string to copy into the new JSString.
@result           A JSString containing string. Ownership follows the Create Rule.
*/
JS_EXPORT JSStringRef JSStringCreateWithUTF8CString(const char* string);

/*!
@function
@abstract         Retains a JavaScript string.
@param string     The JSString to retain.
@result           A JSString that is the same as string.
*/
JS_EXPORT JSStringRef JSStringRetain(JSStringRef string);
/*!
@function
@abstract         Releases a JavaScript string.
@param string     The JSString to release.
*/
JS_EXPORT void JSStringRelease(JSStringRef string);

/*!
@function
@abstract         Returns the number of Unicode characters in a JavaScript string.
@param string     The JSString whose length (in Unicode characters) you want to know.
@result           The number of Unicode characters stored in string.
*/
JS_EXPORT size_t JSStringGetLength(JSStringRef string);
/*!
@function
@abstract         Returns a pointer to the Unicode character buffer that 
 serves as the backing store for a JavaScript string.
@param string     The JSString whose backing store you want to access.
@result           A pointer to the Unicode character buffer that serves as string's 
 backing store, which will be deallocated when string is deallocated.
*/
JS_EXPORT const JSChar* JSStringGetCharactersPtr(JSStringRef string);

/*!
@function
@abstract Returns the maximum number of bytes a JavaScript string will 
 take up if converted into a null-terminated UTF8 string.
@param string The JSString whose maximum converted size (in bytes) you 
 want to know.
@result The maximum number of bytes that could be required to convert string into a 
 null-terminated UTF8 string. The number of bytes that the conversion actually ends 
 up requiring could be less than this, but never more.
*/
JS_EXPORT size_t JSStringGetMaximumUTF8CStringSize(JSStringRef string);
/*!
@function
@abstract Converts a JavaScript string into a null-terminated UTF8 string, 
 and copies the result into an external byte buffer.
@param string The source JSString.
@param buffer The destination byte buffer into which to copy a null-terminated 
 UTF8 representation of string. On return, buffer contains a UTF8 string 
 representation of string. If bufferSize is too small, buffer will contain only 
 partial results. If buffer is not at least bufferSize bytes in size, 
 behavior is undefined. 
@param bufferSize The size of the external buffer in bytes.
@result The number of bytes written into buffer (including the null-terminator byte).
*/
JS_EXPORT size_t JSStringGetUTF8CString(JSStringRef string, char* buffer, size_t bufferSize);

/*!
@function
@abstract     Tests whether two JavaScript strings match.
@param a      The first JSString to test.
@param b      The second JSString to test.
@result       true if the two strings match, otherwise false.
*/
JS_EXPORT bool JSStringIsEqual(JSStringRef a, JSStringRef b);
/*!
@function
@abstract     Tests whether a JavaScript string matches a null-terminated UTF8 string.
@param a      The JSString to test.
@param b      The null-terminated UTF8 string to test.
@result       true if the two strings match, otherwise false.
*/
JS_EXPORT bool JSStringIsEqualToUTF8CString(JSStringRef a, const char* b);

#ifdef __cplusplus
}
#endif

#endif /* JSStringRef_h */
='#n508'>508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045
/* ------------------------------------------------------------------------

   Python Codec Registry and support functions

Written by Marc-Andre Lemburg (mal@lemburg.com).

Copyright (c) Corporation for National Research Initiatives.

   ------------------------------------------------------------------------ */

#include "Python.h"
#include <ctype.h>

/* --- Codec Registry ----------------------------------------------------- */

/* Import the standard encodings package which will register the first
   codec search function.

   This is done in a lazy way so that the Unicode implementation does
   not downgrade startup time of scripts not needing it.

   ImportErrors are silently ignored by this function. Only one try is
   made.

*/

static int _PyCodecRegistry_Init(void); /* Forward */

int PyCodec_Register(PyObject *search_function)
{
    PyInterpreterState *interp = PyThreadState_GET()->interp;
    if (interp->codec_search_path == NULL && _PyCodecRegistry_Init())
        goto onError;
    if (search_function == NULL) {
        PyErr_BadArgument();
        goto onError;
    }
    if (!PyCallable_Check(search_function)) {
        PyErr_SetString(PyExc_TypeError, "argument must be callable");
        goto onError;
    }
    return PyList_Append(interp->codec_search_path, search_function);

 onError:
    return -1;
}

/* Convert a string to a normalized Python string: all characters are
   converted to lower case, spaces are replaced with underscores. */

static
PyObject *normalizestring(const char *string)
{
    register size_t i;
    size_t len = strlen(string);
    char *p;
    PyObject *v;

    if (len > PY_SSIZE_T_MAX) {
        PyErr_SetString(PyExc_OverflowError, "string is too large");
        return NULL;
    }

    v = PyString_FromStringAndSize(NULL, len);
    if (v == NULL)
        return NULL;
    p = PyString_AS_STRING(v);
    for (i = 0; i < len; i++) {
        register char ch = string[i];
        if (ch == ' ')
            ch = '-';
        else
            ch = Py_TOLOWER(Py_CHARMASK(ch));
        p[i] = ch;
    }
    return v;
}

/* Lookup the given encoding and return a tuple providing the codec
   facilities.

   The encoding string is looked up converted to all lower-case
   characters. This makes encodings looked up through this mechanism
   effectively case-insensitive.

   If no codec is found, a LookupError is set and NULL returned.

   As side effect, this tries to load the encodings package, if not
   yet done. This is part of the lazy load strategy for the encodings
   package.

*/

PyObject *_PyCodec_Lookup(const char *encoding)
{
    PyInterpreterState *interp;
    PyObject *result, *args = NULL, *v;
    Py_ssize_t i, len;

    if (encoding == NULL) {
        PyErr_BadArgument();
        goto onError;
    }

    interp = PyThreadState_GET()->interp;
    if (interp->codec_search_path == NULL && _PyCodecRegistry_Init())
        goto onError;

    /* Convert the encoding to a normalized Python string: all
       characters are converted to lower case, spaces and hyphens are
       replaced with underscores. */
    v = normalizestring(encoding);
    if (v == NULL)
        goto onError;
    PyString_InternInPlace(&v);

    /* First, try to lookup the name in the registry dictionary */
    result = PyDict_GetItem(interp->codec_search_cache, v);
    if (result != NULL) {
        Py_INCREF(result);
        Py_DECREF(v);
        return result;
    }

    /* Next, scan the search functions in order of registration */
    args = PyTuple_New(1);
    if (args == NULL)
        goto onError;
    PyTuple_SET_ITEM(args,0,v);

    len = PyList_Size(interp->codec_search_path);
    if (len < 0)
        goto onError;
    if (len == 0) {
        PyErr_SetString(PyExc_LookupError,
                        "no codec search functions registered: "
                        "can't find encoding");
        goto onError;
    }

    for (i = 0; i < len; i++) {
        PyObject *func;

        func = PyList_GetItem(interp->codec_search_path, i);
        if (func == NULL)
            goto onError;
        result = PyEval_CallObject(func, args);
        if (result == NULL)
            goto onError;
        if (result == Py_None) {
            Py_DECREF(result);
            continue;
        }
        if (!PyTuple_Check(result) || PyTuple_GET_SIZE(result) != 4) {
            PyErr_SetString(PyExc_TypeError,
                            "codec search functions must return 4-tuples");
            Py_DECREF(result);
            goto onError;
        }
        break;
    }
    if (i == len) {
        /* XXX Perhaps we should cache misses too ? */
        PyErr_Format(PyExc_LookupError,
                     "unknown encoding: %s", encoding);
        goto onError;
    }

    /* Cache and return the result */
    PyDict_SetItem(interp->codec_search_cache, v, result);
    Py_DECREF(args);
    return result;

 onError:
    Py_XDECREF(args);
    return NULL;
}

static
PyObject *args_tuple(PyObject *object,
                     const char *errors)
{
    PyObject *args;

    args = PyTuple_New(1 + (errors != NULL));
    if (args == NULL)
        return NULL;
    Py_INCREF(object);
    PyTuple_SET_ITEM(args,0,object);
    if (errors) {
        PyObject *v;

        v = PyString_FromString(errors);
        if (v == NULL) {
            Py_DECREF(args);
            return NULL;
        }
        PyTuple_SET_ITEM(args, 1, v);
    }
    return args;
}

/* Helper function to get a codec item */

static
PyObject *codec_getitem(const char *encoding, int index)
{
    PyObject *codecs;
    PyObject *v;

    codecs = _PyCodec_Lookup(encoding);
    if (codecs == NULL)
        return NULL;
    v = PyTuple_GET_ITEM(codecs, index);
    Py_DECREF(codecs);
    Py_INCREF(v);
    return v;
}

/* Helper functions to create an incremental codec. */
static
PyObject *codec_makeincrementalcodec(PyObject *codec_info,
                                     const char *errors,
                                     const char *attrname)
{
    PyObject *ret, *inccodec;

    inccodec = PyObject_GetAttrString(codec_info, attrname);
    if (inccodec == NULL)
        return NULL;
    if (errors)
        ret = PyObject_CallFunction(inccodec, "s", errors);
    else
        ret = PyObject_CallFunction(inccodec, NULL);
    Py_DECREF(inccodec);
    return ret;
}

static
PyObject *codec_getincrementalcodec(const char *encoding,
                                    const char *errors,
                                    const char *attrname)
{
    PyObject *codec_info, *ret;

    codec_info = _PyCodec_Lookup(encoding);
    if (codec_info == NULL)
        return NULL;
    ret = codec_makeincrementalcodec(codec_info, errors, attrname);
    Py_DECREF(codec_info);
    return ret;
}

/* Helper function to create a stream codec. */

static
PyObject *codec_getstreamcodec(const char *encoding,
                               PyObject *stream,
                               const char *errors,
                               const int index)
{
    PyObject *codecs, *streamcodec, *codeccls;

    codecs = _PyCodec_Lookup(encoding);
    if (codecs == NULL)
        return NULL;

    codeccls = PyTuple_GET_ITEM(codecs, index);
    if (errors != NULL)
        streamcodec = PyObject_CallFunction(codeccls, "Os", stream, errors);
    else
        streamcodec = PyObject_CallFunction(codeccls, "O", stream);
    Py_DECREF(codecs);
    return streamcodec;
}

/* Helpers to work with the result of _PyCodec_Lookup

 */
PyObject *_PyCodecInfo_GetIncrementalDecoder(PyObject *codec_info,
                                             const char *errors)
{
    return codec_makeincrementalcodec(codec_info, errors,
                                      "incrementaldecoder");
}

PyObject *_PyCodecInfo_GetIncrementalEncoder(PyObject *codec_info,
                                             const char *errors)
{
    return codec_makeincrementalcodec(codec_info, errors,
                                      "incrementalencoder");
}


/* Convenience APIs to query the Codec registry.

   All APIs return a codec object with incremented refcount.

 */

PyObject *PyCodec_Encoder(const char *encoding)
{
    return codec_getitem(encoding, 0);
}

PyObject *PyCodec_Decoder(const char *encoding)
{
    return codec_getitem(encoding, 1);
}

PyObject *PyCodec_IncrementalEncoder(const char *encoding,
                                     const char *errors)
{
    return codec_getincrementalcodec(encoding, errors, "incrementalencoder");
}

PyObject *PyCodec_IncrementalDecoder(const char *encoding,
                                     const char *errors)
{
    return codec_getincrementalcodec(encoding, errors, "incrementaldecoder");
}

PyObject *PyCodec_StreamReader(const char *encoding,
                               PyObject *stream,
                               const char *errors)
{
    return codec_getstreamcodec(encoding, stream, errors, 2);
}

PyObject *PyCodec_StreamWriter(const char *encoding,
                               PyObject *stream,
                               const char *errors)
{
    return codec_getstreamcodec(encoding, stream, errors, 3);
}

/* Encode an object (e.g. a Unicode object) using the given encoding
   and return the resulting encoded object (usually a Python string).

   errors is passed to the encoder factory as argument if non-NULL. */

static PyObject *
_PyCodec_EncodeInternal(PyObject *object,
                        PyObject *encoder,
                        const char *encoding,
                        const char *errors)
{
    PyObject *args = NULL, *result = NULL;
    PyObject *v;

    args = args_tuple(object, errors);
    if (args == NULL)
        goto onError;

    result = PyEval_CallObject(encoder,args);
    if (result == NULL)
        goto onError;

    if (!PyTuple_Check(result) ||
        PyTuple_GET_SIZE(result) != 2) {
        PyErr_SetString(PyExc_TypeError,
                        "encoder must return a tuple (object,integer)");
        goto onError;
    }
    v = PyTuple_GET_ITEM(result,0);
    Py_INCREF(v);
    /* We don't check or use the second (integer) entry. */

    Py_DECREF(args);
    Py_DECREF(encoder);
    Py_DECREF(result);
    return v;

 onError:
    Py_XDECREF(result);
    Py_XDECREF(args);
    Py_XDECREF(encoder);
    return NULL;
}

/* Decode an object (usually a Python string) using the given encoding
   and return an equivalent object (e.g. a Unicode object).

   errors is passed to the decoder factory as argument if non-NULL. */

static PyObject *
_PyCodec_DecodeInternal(PyObject *object,
                        PyObject *decoder,
                        const char *encoding,
                        const char *errors)
{
    PyObject *args = NULL, *result = NULL;
    PyObject *v;

    args = args_tuple(object, errors);
    if (args == NULL)
        goto onError;

    result = PyEval_CallObject(decoder,args);
    if (result == NULL)
        goto onError;
    if (!PyTuple_Check(result) ||
        PyTuple_GET_SIZE(result) != 2) {
        PyErr_SetString(PyExc_TypeError,
                        "decoder must return a tuple (object,integer)");
        goto onError;
    }
    v = PyTuple_GET_ITEM(result,0);
    Py_INCREF(v);
    /* We don't check or use the second (integer) entry. */

    Py_DECREF(args);
    Py_DECREF(decoder);
    Py_DECREF(result);
    return v;

 onError:
    Py_XDECREF(args);
    Py_XDECREF(decoder);
    Py_XDECREF(result);
    return NULL;
}

/* Generic encoding/decoding API */
PyObject *PyCodec_Encode(PyObject *object,
                         const char *encoding,
                         const char *errors)
{
    PyObject *encoder;

    encoder = PyCodec_Encoder(encoding);
    if (encoder == NULL)
        return NULL;

    return _PyCodec_EncodeInternal(object, encoder, encoding, errors);
}

PyObject *PyCodec_Decode(PyObject *object,
                         const char *encoding,
                         const char *errors)
{
    PyObject *decoder;

    decoder = PyCodec_Decoder(encoding);
    if (decoder == NULL)
        return NULL;

    return _PyCodec_DecodeInternal(object, decoder, encoding, errors);
}

/* Text encoding/decoding API */
PyObject * _PyCodec_LookupTextEncoding(const char *encoding,
                                       const char *alternate_command)
{
    PyObject *codec;
    PyObject *attr;
    int is_text_codec;

    codec = _PyCodec_Lookup(encoding);
    if (codec == NULL)
        return NULL;

    /* Backwards compatibility: assume any raw tuple describes a text
     * encoding, and the same for anything lacking the private
     * attribute.
     */
    if (Py_Py3kWarningFlag && !PyTuple_CheckExact(codec)) {
        attr = PyObject_GetAttrString(codec, "_is_text_encoding");
        if (attr == NULL) {
            if (!PyErr_ExceptionMatches(PyExc_AttributeError))
                goto onError;
            PyErr_Clear();
        } else {
            is_text_codec = PyObject_IsTrue(attr);
            Py_DECREF(attr);
            if (is_text_codec < 0)
                goto onError;
            if (!is_text_codec) {
                PyObject *msg = PyString_FromFormat(
                            "'%.400s' is not a text encoding; "
                            "use %s to handle arbitrary codecs",
                            encoding, alternate_command);
                if (msg == NULL)
                    goto onError;
                if (PyErr_WarnPy3k(PyString_AS_STRING(msg), 1) < 0) {
                    Py_DECREF(msg);
                    goto onError;
                }
                Py_DECREF(msg);
            }
        }
    }

    /* This appears to be a valid text encoding */
    return codec;

 onError:
    Py_DECREF(codec);
    return NULL;
}


static
PyObject *codec_getitem_checked(const char *encoding,
                                const char *alternate_command,
                                int index)
{
    PyObject *codec;
    PyObject *v;

    codec = _PyCodec_LookupTextEncoding(encoding, alternate_command);
    if (codec == NULL)
        return NULL;

    v = PyTuple_GET_ITEM(codec, index);
    Py_INCREF(v);
    Py_DECREF(codec);
    return v;
}

static PyObject * _PyCodec_TextEncoder(const char *encoding)
{
    return codec_getitem_checked(encoding, "codecs.encode()", 0);
}

static PyObject * _PyCodec_TextDecoder(const char *encoding)
{
    return codec_getitem_checked(encoding, "codecs.decode()", 1);
}

PyObject *_PyCodec_EncodeText(PyObject *object,
                              const char *encoding,
                              const char *errors)
{
    PyObject *encoder;

    encoder = _PyCodec_TextEncoder(encoding);
    if (encoder == NULL)
        return NULL;

    return _PyCodec_EncodeInternal(object, encoder, encoding, errors);
}

PyObject *_PyCodec_DecodeText(PyObject *object,
                              const char *encoding,
                              const char *errors)
{
    PyObject *decoder;

    decoder = _PyCodec_TextDecoder(encoding);
    if (decoder == NULL)
        return NULL;

    return _PyCodec_DecodeInternal(object, decoder, encoding, errors);
}

/* Register the error handling callback function error under the name
   name. This function will be called by the codec when it encounters
   an unencodable characters/undecodable bytes and doesn't know the
   callback name, when name is specified as the error parameter
   in the call to the encode/decode function.
   Return 0 on success, -1 on error */
int PyCodec_RegisterError(const char *name, PyObject *error)
{
    PyInterpreterState *interp = PyThreadState_GET()->interp;
    if (interp->codec_search_path == NULL && _PyCodecRegistry_Init())
        return -1;
    if (!PyCallable_Check(error)) {
        PyErr_SetString(PyExc_TypeError, "handler must be callable");
        return -1;
    }
    return PyDict_SetItemString(interp->codec_error_registry,
                                (char *)name, error);
}

/* Lookup the error handling callback function registered under the
   name error. As a special case NULL can be passed, in which case
   the error handling callback for strict encoding will be returned. */
PyObject *PyCodec_LookupError(const char *name)
{
    PyObject *handler = NULL;

    PyInterpreterState *interp = PyThreadState_GET()->interp;
    if (interp->codec_search_path == NULL && _PyCodecRegistry_Init())
        return NULL;

    if (name==NULL)
        name = "strict";
    handler = PyDict_GetItemString(interp->codec_error_registry, (char *)name);
    if (!handler)
        PyErr_Format(PyExc_LookupError, "unknown error handler name '%.400s'", name);
    else
        Py_INCREF(handler);
    return handler;
}

static void wrong_exception_type(PyObject *exc)
{
    PyObject *type = PyObject_GetAttrString(exc, "__class__");
    if (type != NULL) {
        PyObject *name = PyObject_GetAttrString(type, "__name__");
        Py_DECREF(type);
        if (name != NULL) {
            PyObject *string = PyObject_Str(name);
            Py_DECREF(name);
            if (string != NULL) {
                PyErr_Format(PyExc_TypeError,
                    "don't know how to handle %.400s in error callback",
                    PyString_AS_STRING(string));
                Py_DECREF(string);
            }
        }
    }
}

PyObject *PyCodec_StrictErrors(PyObject *exc)
{
    if (PyExceptionInstance_Check(exc))
        PyErr_SetObject(PyExceptionInstance_Class(exc), exc);
    else
        PyErr_SetString(PyExc_TypeError, "codec must pass exception instance");
    return NULL;
}


#ifdef Py_USING_UNICODE
PyObject *PyCodec_IgnoreErrors(PyObject *exc)
{
    Py_ssize_t end;

    if (PyObject_TypeCheck(exc, (PyTypeObject *)PyExc_UnicodeEncodeError)) {
        if (PyUnicodeEncodeError_GetEnd(exc, &end))
            return NULL;
    }
    else if (PyObject_TypeCheck(exc, (PyTypeObject *)PyExc_UnicodeDecodeError)) {
        if (PyUnicodeDecodeError_GetEnd(exc, &end))
            return NULL;
    }
    else if (PyObject_TypeCheck(exc, (PyTypeObject *)PyExc_UnicodeTranslateError)) {
        if (PyUnicodeTranslateError_GetEnd(exc, &end))
            return NULL;
    }
    else {
        wrong_exception_type(exc);
        return NULL;
    }
    /* ouch: passing NULL, 0, pos gives None instead of u'' */
    return Py_BuildValue("(u#n)", &end, 0, end);
}


PyObject *PyCodec_ReplaceErrors(PyObject *exc)
{
    PyObject *restuple;
    Py_ssize_t start;
    Py_ssize_t end;
    Py_ssize_t i;

    if (PyObject_TypeCheck(exc, (PyTypeObject *)PyExc_UnicodeEncodeError)) {
        PyObject *res;
        Py_UNICODE *p;
        if (PyUnicodeEncodeError_GetStart(exc, &start))
            return NULL;
        if (PyUnicodeEncodeError_GetEnd(exc, &end))
            return NULL;
        res = PyUnicode_FromUnicode(NULL, end-start);
        if (res == NULL)
            return NULL;
        for (p = PyUnicode_AS_UNICODE(res), i = start;
            i<end; ++p, ++i)
            *p = '?';
        restuple = Py_BuildValue("(On)", res, end);
        Py_DECREF(res);
        return restuple;
    }
    else if (PyObject_TypeCheck(exc, (PyTypeObject *)PyExc_UnicodeDecodeError)) {
        Py_UNICODE res = Py_UNICODE_REPLACEMENT_CHARACTER;
        if (PyUnicodeDecodeError_GetEnd(exc, &end))
            return NULL;
        return Py_BuildValue("(u#n)", &res, (Py_ssize_t)1, end);
    }
    else if (PyObject_TypeCheck(exc, (PyTypeObject *)PyExc_UnicodeTranslateError)) {
        PyObject *res;
        Py_UNICODE *p;
        if (PyUnicodeTranslateError_GetStart(exc, &start))
            return NULL;
        if (PyUnicodeTranslateError_GetEnd(exc, &end))
            return NULL;
        res = PyUnicode_FromUnicode(NULL, end-start);
        if (res == NULL)
            return NULL;
        for (p = PyUnicode_AS_UNICODE(res), i = start;
            i<end; ++p, ++i)
            *p = Py_UNICODE_REPLACEMENT_CHARACTER;
        restuple = Py_BuildValue("(On)", res, end);
        Py_DECREF(res);
        return restuple;
    }
    else {
        wrong_exception_type(exc);
        return NULL;
    }
}

PyObject *PyCodec_XMLCharRefReplaceErrors(PyObject *exc)
{
    if (PyObject_TypeCheck(exc, (PyTypeObject *)PyExc_UnicodeEncodeError)) {
        PyObject *restuple;
        PyObject *object;
        Py_ssize_t start;
        Py_ssize_t end;
        PyObject *res;
        Py_UNICODE *p;
        Py_UNICODE *startp;
        Py_UNICODE *e;
        Py_UNICODE *outp;
        Py_ssize_t ressize;
        if (PyUnicodeEncodeError_GetStart(exc, &start))
            return NULL;
        if (PyUnicodeEncodeError_GetEnd(exc, &end))
            return NULL;
        if (!(object = PyUnicodeEncodeError_GetObject(exc)))
            return NULL;
        startp = PyUnicode_AS_UNICODE(object);
        if (end - start > PY_SSIZE_T_MAX / (2+7+1)) {
            end = start + PY_SSIZE_T_MAX / (2+7+1);
#ifndef Py_UNICODE_WIDE
            if (0xD800 <= startp[end - 1] && startp[end - 1] <= 0xDBFF)
                end--;
#endif
        }
        e = startp + end;
        for (p = startp+start, ressize = 0; p < e;) {
            Py_UCS4 ch = *p++;
#ifndef Py_UNICODE_WIDE
            if ((0xD800 <= ch && ch <= 0xDBFF) &&
                (p < e) &&
                (0xDC00 <= *p && *p <= 0xDFFF)) {
                ch = ((((ch & 0x03FF) << 10) |
                       ((Py_UCS4)*p++ & 0x03FF)) + 0x10000);
            }
#endif
            if (ch < 10)
                ressize += 2+1+1;
            else if (ch < 100)
                ressize += 2+2+1;
            else if (ch < 1000)
                ressize += 2+3+1;
            else if (ch < 10000)
                ressize += 2+4+1;
            else if (ch < 100000)
                ressize += 2+5+1;
            else if (ch < 1000000)
                ressize += 2+6+1;
            else
                ressize += 2+7+1;
        }
        /* allocate replacement */
        res = PyUnicode_FromUnicode(NULL, ressize);
        if (res == NULL) {
            Py_DECREF(object);
            return NULL;
        }
        /* generate replacement */
        for (p = startp+start, outp = PyUnicode_AS_UNICODE(res); p < e;) {
            int digits;
            int base;
            Py_UCS4 ch = *p++;
#ifndef Py_UNICODE_WIDE
            if ((0xD800 <= ch && ch <= 0xDBFF) &&
                (p < startp+end) &&
                (0xDC00 <= *p && *p <= 0xDFFF)) {
                ch = ((((ch & 0x03FF) << 10) |
                       ((Py_UCS4)*p++ & 0x03FF)) + 0x10000);
            }
#endif
            *outp++ = '&';
            *outp++ = '#';
            if (ch < 10) {
                digits = 1;
                base = 1;
            }
            else if (ch < 100) {
                digits = 2;
                base = 10;
            }
            else if (ch < 1000) {
                digits = 3;
                base = 100;
            }
            else if (ch < 10000) {
                digits = 4;
                base = 1000;
            }
            else if (ch < 100000) {
                digits = 5;
                base = 10000;
            }
            else if (ch < 1000000) {
                digits = 6;
                base = 100000;
            }
            else {
                digits = 7;
                base = 1000000;
            }
            while (digits-->0) {
                *outp++ = '0' + ch/base;
                ch %= base;
                base /= 10;
            }
            *outp++ = ';';
        }
        restuple = Py_BuildValue("(On)", res, end);
        Py_DECREF(res);
        Py_DECREF(object);
        return restuple;
    }
    else {
        wrong_exception_type(exc);
        return NULL;
    }
}

static Py_UNICODE hexdigits[] = {
    '0', '1', '2', '3', '4', '5', '6', '7',
    '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'
};

PyObject *PyCodec_BackslashReplaceErrors(PyObject *exc)
{
    if (PyObject_TypeCheck(exc, (PyTypeObject *)PyExc_UnicodeEncodeError)) {
        PyObject *restuple;
        PyObject *object;
        Py_ssize_t start;
        Py_ssize_t end;
        PyObject *res;
        Py_UNICODE *p;
        Py_UNICODE *startp;
        Py_UNICODE *outp;
        Py_ssize_t ressize;
        if (PyUnicodeEncodeError_GetStart(exc, &start))
            return NULL;
        if (PyUnicodeEncodeError_GetEnd(exc, &end))
            return NULL;
        if (!(object = PyUnicodeEncodeError_GetObject(exc)))
            return NULL;
        if (end - start > PY_SSIZE_T_MAX / (1+1+8))
            end = start + PY_SSIZE_T_MAX / (1+1+8);
        startp = PyUnicode_AS_UNICODE(object);
        for (p = startp+start, ressize = 0; p < startp+end; ++p) {
#ifdef Py_UNICODE_WIDE
            if (*p >= 0x00010000)
                ressize += 1+1+8;
            else
#endif
            if (*p >= 0x100) {
                ressize += 1+1+4;
            }
            else
                ressize += 1+1+2;
        }
        res = PyUnicode_FromUnicode(NULL, ressize);
        if (res == NULL) {
            Py_DECREF(object);
            return NULL;
        }
        for (p = startp+start, outp = PyUnicode_AS_UNICODE(res);
            p < startp+end; ++p) {
            Py_UNICODE c = *p;
            *outp++ = '\\';
#ifdef Py_UNICODE_WIDE
            if (c >= 0x00010000) {
                *outp++ = 'U';
                *outp++ = hexdigits[(c>>28)&0xf];
                *outp++ = hexdigits[(c>>24)&0xf];
                *outp++ = hexdigits[(c>>20)&0xf];
                *outp++ = hexdigits[(c>>16)&0xf];
                *outp++ = hexdigits[(c>>12)&0xf];
                *outp++ = hexdigits[(c>>8)&0xf];
            }
            else
#endif
            if (c >= 0x100) {
                *outp++ = 'u';
                *outp++ = hexdigits[(c>>12)&0xf];
                *outp++ = hexdigits[(c>>8)&0xf];
            }
            else
                *outp++ = 'x';
            *outp++ = hexdigits[(c>>4)&0xf];
            *outp++ = hexdigits[c&0xf];
        }

        restuple = Py_BuildValue("(On)", res, end);
        Py_DECREF(res);
        Py_DECREF(object);
        return restuple;
    }
    else {
        wrong_exception_type(exc);
        return NULL;
    }
}
#endif

static PyObject *strict_errors(PyObject *self, PyObject *exc)
{
    return PyCodec_StrictErrors(exc);
}


#ifdef Py_USING_UNICODE
static PyObject *ignore_errors(PyObject *self, PyObject *exc)
{
    return PyCodec_IgnoreErrors(exc);
}


static PyObject *replace_errors(PyObject *self, PyObject *exc)
{
    return PyCodec_ReplaceErrors(exc);
}


static PyObject *xmlcharrefreplace_errors(PyObject *self, PyObject *exc)
{
    return PyCodec_XMLCharRefReplaceErrors(exc);
}


static PyObject *backslashreplace_errors(PyObject *self, PyObject *exc)
{
    return PyCodec_BackslashReplaceErrors(exc);
}
#endif

static int _PyCodecRegistry_Init(void)
{
    static struct {
        char *name;
        PyMethodDef def;
    } methods[] =
    {
        {
            "strict",
            {
                "strict_errors",
                strict_errors,
                METH_O,
                PyDoc_STR("Implements the 'strict' error handling, which "
                          "raises a UnicodeError on coding errors.")
            }
        },
#ifdef Py_USING_UNICODE
        {
            "ignore",
            {
                "ignore_errors",
                ignore_errors,
                METH_O,
                PyDoc_STR("Implements the 'ignore' error handling, which "
                          "ignores malformed data and continues.")
            }
        },
        {
            "replace",
            {
                "replace_errors",
                replace_errors,
                METH_O,
                PyDoc_STR("Implements the 'replace' error handling, which "
                          "replaces malformed data with a replacement marker.")
            }
        },
        {
            "xmlcharrefreplace",
            {
                "xmlcharrefreplace_errors",
                xmlcharrefreplace_errors,
                METH_O,
                PyDoc_STR("Implements the 'xmlcharrefreplace' error handling, "
                          "which replaces an unencodable character with the "
                          "appropriate XML character reference.")
            }
        },
        {
            "backslashreplace",
            {
                "backslashreplace_errors",
                backslashreplace_errors,
                METH_O,
                PyDoc_STR("Implements the 'backslashreplace' error handling, "
                          "which replaces an unencodable character with a "
                          "backslashed escape sequence.")
            }
        }
#endif
    };

    PyInterpreterState *interp = PyThreadState_GET()->interp;
    PyObject *mod;
    unsigned i;

    if (interp->codec_search_path != NULL)
        return 0;

    interp->codec_search_path = PyList_New(0);
    interp->codec_search_cache = PyDict_New();
    interp->codec_error_registry = PyDict_New();

    if (interp->codec_error_registry) {
        for (i = 0; i < sizeof(methods)/sizeof(methods[0]); ++i) {
            PyObject *func = PyCFunction_New(&methods[i].def, NULL);
            int res;
            if (!func)
                Py_FatalError("can't initialize codec error registry");
            res = PyCodec_RegisterError(methods[i].name, func);
            Py_DECREF(func);
            if (res)
                Py_FatalError("can't initialize codec error registry");
        }
    }

    if (interp->codec_search_path == NULL ||
        interp->codec_search_cache == NULL ||
        interp->codec_error_registry == NULL)
        Py_FatalError("can't initialize codec registry");

    mod = PyImport_ImportModuleLevel("encodings", NULL, NULL, NULL, 0);
    if (mod == NULL) {
        if (PyErr_ExceptionMatches(PyExc_ImportError)) {
            /* Ignore ImportErrors... this is done so that
               distributions can disable the encodings package. Note
               that other errors are not masked, e.g. SystemErrors
               raised to inform the user of an error in the Python
               configuration are still reported back to the user. */
            PyErr_Clear();
            return 0;
        }
        return -1;
    }
    Py_DECREF(mod);
    return 0;
}