1/*
2 * Copyright (C) 2007, 2008 Apple, Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 *    notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 *    notice, this list of conditions and the following disclaimer in the
11 *    documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#include "config.h"
27#include "wtf/text/TextCodecUserDefined.h"
28
29#include <stdio.h>
30#include "wtf/PassOwnPtr.h"
31#include "wtf/text/CString.h"
32#include "wtf/text/StringBuffer.h"
33#include "wtf/text/StringBuilder.h"
34#include "wtf/text/WTFString.h"
35
36namespace WTF {
37
38void TextCodecUserDefined::registerEncodingNames(EncodingNameRegistrar registrar)
39{
40    registrar("x-user-defined", "x-user-defined");
41}
42
43static PassOwnPtr<TextCodec> newStreamingTextDecoderUserDefined(const TextEncoding&, const void*)
44{
45    return adoptPtr(new TextCodecUserDefined);
46}
47
48void TextCodecUserDefined::registerCodecs(TextCodecRegistrar registrar)
49{
50    registrar("x-user-defined", newStreamingTextDecoderUserDefined, 0);
51}
52
53String TextCodecUserDefined::decode(const char* bytes, size_t length, bool, bool, bool&)
54{
55    StringBuilder result;
56    result.reserveCapacity(length);
57
58    for (size_t i = 0; i < length; ++i) {
59        signed char c = bytes[i];
60        result.append(static_cast<UChar>(c & 0xF7FF));
61    }
62
63    return result.toString();
64}
65
66template<typename CharType>
67static CString encodeComplexUserDefined(const CharType* characters, size_t length, UnencodableHandling handling)
68{
69    Vector<char> result(length);
70    char* bytes = result.data();
71
72    size_t resultLength = 0;
73    for (size_t i = 0; i < length; ) {
74        UChar32 c;
75        U16_NEXT(characters, i, length, c);
76        signed char signedByte = c;
77        if ((signedByte & 0xF7FF) == c)
78            bytes[resultLength++] = signedByte;
79        else {
80            // No way to encode this character with x-user-defined.
81            UnencodableReplacementArray replacement;
82            int replacementLength = TextCodec::getUnencodableReplacement(c, handling, replacement);
83            result.grow(resultLength + replacementLength + length - i);
84            bytes = result.data();
85            memcpy(bytes + resultLength, replacement, replacementLength);
86            resultLength += replacementLength;
87        }
88    }
89
90    return CString(bytes, resultLength);
91}
92
93template<typename CharType>
94CString TextCodecUserDefined::encodeCommon(const CharType* characters, size_t length, UnencodableHandling handling)
95{
96    char* bytes;
97    CString result = CString::newUninitialized(length, bytes);
98
99    // Convert the string a fast way and simultaneously do an efficient check to see if it's all ASCII.
100    UChar ored = 0;
101    for (size_t i = 0; i < length; ++i) {
102        UChar c = characters[i];
103        bytes[i] = c;
104        ored |= c;
105    }
106
107    if (!(ored & 0xFF80))
108        return result;
109
110    // If it wasn't all ASCII, call the function that handles more-complex cases.
111    return encodeComplexUserDefined(characters, length, handling);
112}
113
114CString TextCodecUserDefined::encode(const UChar* characters, size_t length, UnencodableHandling handling)
115{
116    return encodeCommon(characters, length, handling);
117}
118
119CString TextCodecUserDefined::encode(const LChar* characters, size_t length, UnencodableHandling handling)
120{
121    return encodeCommon(characters, length, handling);
122}
123
124} // namespace WTF
125