1/*
2 * Copyright (C) 2007 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#ifndef WTF_UTF8_h
27#define WTF_UTF8_h
28
29#include "Unicode.h"
30
31namespace WTF {
32namespace Unicode {
33
34    // Given a first byte, gives the length of the UTF-8 sequence it begins.
35    // Returns 0 for bytes that are not legal starts of UTF-8 sequences.
36    // Only allows sequences of up to 4 bytes, since that works for all Unicode characters (U-00000000 to U-0010FFFF).
37    int UTF8SequenceLength(char);
38
39    // Takes a null-terminated C-style string with a UTF-8 sequence in it and converts it to a character.
40    // Only allows Unicode characters (U-00000000 to U-0010FFFF).
41    // Returns -1 if the sequence is not valid (including presence of extra bytes).
42    int decodeUTF8Sequence(const char*);
43
44    typedef enum {
45            conversionOK,       // conversion successful
46            sourceExhausted,    // partial character in source, but hit end
47            targetExhausted,    // insuff. room in target for conversion
48            sourceIllegal       // source sequence is illegal/malformed
49    } ConversionResult;
50
51    // These conversion functions take a "strict" argument. When this
52    // flag is set to strict, both irregular sequences and isolated surrogates
53    // will cause an error.  When the flag is set to lenient, both irregular
54    // sequences and isolated surrogates are converted.
55    //
56    // Whether the flag is strict or lenient, all illegal sequences will cause
57    // an error return. This includes sequences such as: <F4 90 80 80>, <C0 80>,
58    // or <A0> in UTF-8, and values above 0x10FFFF in UTF-32. Conformant code
59    // must check for illegal sequences.
60    //
61    // When the flag is set to lenient, characters over 0x10FFFF are converted
62    // to the replacement character; otherwise (when the flag is set to strict)
63    // they constitute an error.
64
65    ConversionResult convertUTF8ToUTF16(
66                    const char** sourceStart, const char* sourceEnd,
67                    UChar** targetStart, UChar* targetEnd, bool strict = true);
68
69    ConversionResult convertUTF16ToUTF8(
70                    const UChar** sourceStart, const UChar* sourceEnd,
71                    char** targetStart, char* targetEnd, bool strict = true);
72
73    unsigned calculateStringHashAndLengthFromUTF8(const char* data, const char* dataEnd, unsigned& dataLength, unsigned& utf16Length);
74
75    bool equalUTF16WithUTF8(const UChar* a, const UChar* aEnd, const char* b, const char* bEnd);
76
77} // namespace Unicode
78} // namespace WTF
79
80#endif // WTF_UTF8_h
81