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 
90 #ifndef REPLXX_CONVERT_UTF8_H_INCLUDED
91 #define REPLXX_CONVERT_UTF8_H_INCLUDED 1
92 
93 #if 0
94 typedef unsigned long	UTF32; /* at least 32 bits */
95 typedef unsigned short UTF16; /* at least 16 bits */
96 typedef unsigned char	UTF8;	/* typically 8 bits */
97 #endif
98 
99 #include <stdint.h>
100 #include <string>
101 
102 namespace replxx {
103 
104 typedef uint32_t      UTF32;
105 typedef uint16_t      UTF16;
106 typedef uint8_t       UTF8;
107 
108 /* Some fundamental constants */
109 #define UNI_REPLACEMENT_CHAR (UTF32)0x0000FFFD
110 #define UNI_MAX_BMP (UTF32)0x0000FFFF
111 #define UNI_MAX_UTF16 (UTF32)0x0010FFFF
112 #define UNI_MAX_UTF32 (UTF32)0x7FFFFFFF
113 #define UNI_MAX_LEGAL_UTF32 (UTF32)0x0010FFFF
114 
115 typedef enum {
116 				conversionOK,    /* conversion successful */
117 				sourceExhausted, /* partial character in source, but hit end */
118 				targetExhausted, /* insuff. room in target for conversion */
119 				sourceIllegal    /* source sequence is illegal/malformed */
120 } ConversionResult;
121 
122 typedef enum {
123 				strictConversion = 0,
124 				lenientConversion
125 } ConversionFlags;
126 
127 ConversionResult ConvertUTF8toUTF32 (
128 								const UTF8** sourceStart, const UTF8* sourceEnd,
129 								UTF32** targetStart, UTF32* targetEnd, ConversionFlags flags);
130 
131 ConversionResult ConvertUTF32toUTF8 (
132 								const UTF32** sourceStart, const UTF32* sourceEnd,
133 								UTF8** targetStart, UTF8* targetEnd, ConversionFlags flags);
134 
135 }
136 
137 #endif /* REPLXX_CONVERT_UTF8_H_INCLUDED */
138 
139 /* --------------------------------------------------------------------- */
140