1/*
2 * Copyright 2001-2004 Unicode, Inc.
3 *
4 * Disclaimer
5 *
6 * This source code is provided as is by Unicode, Inc. No claims are
7 * made as to fitness for any particular purpose. No warranties of any
8 * kind are expressed or implied. The recipient agrees to determine
9 * applicability of information provided. If this file has been
10 * purchased on magnetic or optical media from Unicode, Inc., the
11 * sole remedy for any claim will be exchange of defective media
12 * within 90 days of receipt.
13 *
14 * Limitations on Rights to Redistribute This Code
15 *
16 * Unicode, Inc. hereby grants the right to freely use the information
17 * supplied in this file in the creation of products supporting the
18 * Unicode Standard, and to make copies of this file in any form
19 * for internal or external distribution as long as this notice
20 * remains attached.
21 */
22
23/* ---------------------------------------------------------------------
24
25 Conversions between UTF32, UTF-16, and UTF-8. Header file.
26
27 Several funtions are included here, forming a complete set of
28 conversions between the three formats. UTF-7 is not included
29 here, but is handled in a separate source file.
30
31 Each of these routines takes pointers to input buffers and output
32 buffers. The input buffers are const.
33
34 Each routine converts the text between *sourceStart and sourceEnd,
35 putting the result into the buffer between *targetStart and
36 targetEnd. Note: the end pointers are *after* the last item: e.g.
37 *(sourceEnd - 1) is the last item.
38
39 The return result indicates whether the conversion was successful,
40 and if not, whether the problem was in the source or target buffers.
41 (Only the first encountered problem is indicated.)
42
43 After the conversion, *sourceStart and *targetStart are both
44 updated to point to the end of last text successfully converted in
45 the respective buffers.
46
47 Input parameters:
48 sourceStart - pointer to a pointer to the source buffer.
49 The contents of this are modified on return so that
50 it points at the next thing to be converted.
51 targetStart - similarly, pointer to pointer to the target buffer.
52 sourceEnd, targetEnd - respectively pointers to the ends of the
53 two buffers, for overflow checking only.
54
55 These conversion functions take a ConversionFlags argument. When this
56 flag is set to strict, both irregular sequences and isolated surrogates
57 will cause an error. When the flag is set to lenient, both irregular
58 sequences and isolated surrogates are converted.
59
60 Whether the flag is strict or lenient, all illegal sequences will cause
61 an error return. This includes sequences such as: <F4 90 80 80>, <C0 80>,
62 or <A0> in UTF-8, and values above 0x10FFFF in UTF-32. Conformant code
63 must check for illegal sequences.
64
65 When the flag is set to lenient, characters over 0x10FFFF are converted
66 to the replacement character; otherwise (when the flag is set to strict)
67 they constitute an error.
68
69 Output parameters:
70 The value "sourceIllegal" is returned from some routines if the input
71 sequence is malformed. When "sourceIllegal" is returned, the source
72 value will point to the illegal value that caused the problem. E.g.,
73 in UTF-8 when a sequence is malformed, it points to the start of the
74 malformed sequence.
75
76 Author: Mark E. Davis, 1994.
77 Rev History: Rick McGowan, fixes & updates May 2001.
78 Fixes & updates, Sept 2001.
79
80------------------------------------------------------------------------ */
81
82/* ---------------------------------------------------------------------
83 The following 4 definitions are compiler-specific.
84 The C standard does not guarantee that wchar_t has at least
85 16 bits, so wchar_t is no less portable than unsigned short!
86 All should be unsigned values to avoid sign extension during
87 bit mask & shift operations.
88------------------------------------------------------------------------ */
89
90typedef unsigned int UTF32; /* at least 32 bits */
91typedef unsigned short UTF16; /* at least 16 bits */
92typedef unsigned char UTF8; /* typically 8 bits */
93typedef unsigned char Boolean; /* 0 or 1 */
94
95/* Some fundamental constants */
96#define UNI_REPLACEMENT_CHAR (UTF32)0x0000FFFD
97#define UNI_MAX_BMP (UTF32)0x0000FFFF
98#define UNI_MAX_UTF16 (UTF32)0x0010FFFF
99#define UNI_MAX_UTF32 (UTF32)0x7FFFFFFF
100#define UNI_MAX_LEGAL_UTF32 (UTF32)0x0010FFFF
101
102typedef enum {
103 conversionOK, /* conversion successful */
104 sourceExhausted, /* partial character in source, but hit end */
105 targetExhausted, /* insuff. room in target for conversion */
106 sourceIllegal /* source sequence is illegal/malformed */
107} ConversionResult;
108
109typedef enum {
110 strictConversion = 0,
111 lenientConversion
112} ConversionFlags;
113
114/* This is for C++ and does no harm in C */
115#ifdef __cplusplus
116extern "C" {
117#endif
118
119ConversionResult ConvertUTF8toUTF16 (
120 const UTF8** sourceStart, const UTF8* sourceEnd,
121 UTF16** targetStart, UTF16* targetEnd, ConversionFlags flags);
122
123ConversionResult ConvertUTF16toUTF8 (
124 const UTF16** sourceStart, const UTF16* sourceEnd,
125 UTF8** targetStart, UTF8* targetEnd, ConversionFlags flags);
126
127ConversionResult ConvertUTF8toUTF32 (
128 const UTF8** sourceStart, const UTF8* sourceEnd,
129 UTF32** targetStart, UTF32* targetEnd, ConversionFlags flags);
130
131ConversionResult ConvertUTF32toUTF8 (
132 const UTF32** sourceStart, const UTF32* sourceEnd,
133 UTF8** targetStart, UTF8* targetEnd, ConversionFlags flags);
134
135ConversionResult ConvertUTF16toUTF32 (
136 const UTF16** sourceStart, const UTF16* sourceEnd,
137 UTF32** targetStart, UTF32* targetEnd, ConversionFlags flags);
138
139ConversionResult ConvertUTF32toUTF16 (
140 const UTF32** sourceStart, const UTF32* sourceEnd,
141 UTF16** targetStart, UTF16* targetEnd, ConversionFlags flags);
142
143Boolean isLegalUTF8Sequence(const UTF8 *source, const UTF8 *sourceEnd);
144
145#ifdef __cplusplus
146}
147#endif
148
149/* --------------------------------------------------------------------- */
150