annotate trunk/src/Support/ConvertUTF.h @ 706:f8e90b5d85fd tip

Delete CARFAC code from this repository. It has been moved to https://github.com/google/carfac Please email me with your github username to get access. I've also created a new mailing list to discuss CARFAC development: https://groups.google.com/forum/#!forum/carfac-dev
author ronw@google.com
date Thu, 18 Jul 2013 20:56:51 +0000
parents e14c70d1b171
children
rev   line source
tomwalters@268 1 /*
tomwalters@268 2 * Copyright 2001-2004 Unicode, Inc.
tomwalters@268 3 *
tomwalters@268 4 * Disclaimer
tomwalters@268 5 *
tomwalters@268 6 * This source code is provided as is by Unicode, Inc. No claims are
tomwalters@268 7 * made as to fitness for any particular purpose. No warranties of any
tomwalters@268 8 * kind are expressed or implied. The recipient agrees to determine
tomwalters@268 9 * applicability of information provided. If this file has been
tomwalters@268 10 * purchased on magnetic or optical media from Unicode, Inc., the
tomwalters@268 11 * sole remedy for any claim will be exchange of defective media
tomwalters@268 12 * within 90 days of receipt.
tomwalters@268 13 *
tomwalters@268 14 * Limitations on Rights to Redistribute This Code
tomwalters@268 15 *
tomwalters@268 16 * Unicode, Inc. hereby grants the right to freely use the information
tomwalters@268 17 * supplied in this file in the creation of products supporting the
tomwalters@268 18 * Unicode Standard, and to make copies of this file in any form
tomwalters@268 19 * for internal or external distribution as long as this notice
tomwalters@268 20 * remains attached.
tomwalters@268 21 */
tomwalters@268 22
tomwalters@268 23 /* ---------------------------------------------------------------------
tomwalters@268 24
tomwalters@268 25 Conversions between UTF32, UTF-16, and UTF-8. Header file.
tomwalters@268 26
tomwalters@268 27 Several funtions are included here, forming a complete set of
tomwalters@268 28 conversions between the three formats. UTF-7 is not included
tomwalters@268 29 here, but is handled in a separate source file.
tomwalters@268 30
tomwalters@268 31 Each of these routines takes pointers to input buffers and output
tomwalters@268 32 buffers. The input buffers are const.
tomwalters@268 33
tomwalters@268 34 Each routine converts the text between *sourceStart and sourceEnd,
tomwalters@268 35 putting the result into the buffer between *targetStart and
tomwalters@268 36 targetEnd. Note: the end pointers are *after* the last item: e.g.
tomwalters@268 37 *(sourceEnd - 1) is the last item.
tomwalters@268 38
tomwalters@268 39 The return result indicates whether the conversion was successful,
tomwalters@268 40 and if not, whether the problem was in the source or target buffers.
tomwalters@268 41 (Only the first encountered problem is indicated.)
tomwalters@268 42
tomwalters@268 43 After the conversion, *sourceStart and *targetStart are both
tomwalters@268 44 updated to point to the end of last text successfully converted in
tomwalters@268 45 the respective buffers.
tomwalters@268 46
tomwalters@268 47 Input parameters:
tomwalters@268 48 sourceStart - pointer to a pointer to the source buffer.
tomwalters@268 49 The contents of this are modified on return so that
tomwalters@268 50 it points at the next thing to be converted.
tomwalters@268 51 targetStart - similarly, pointer to pointer to the target buffer.
tomwalters@268 52 sourceEnd, targetEnd - respectively pointers to the ends of the
tomwalters@268 53 two buffers, for overflow checking only.
tomwalters@268 54
tomwalters@268 55 These conversion functions take a ConversionFlags argument. When this
tomwalters@268 56 flag is set to strict, both irregular sequences and isolated surrogates
tomwalters@268 57 will cause an error. When the flag is set to lenient, both irregular
tomwalters@268 58 sequences and isolated surrogates are converted.
tomwalters@268 59
tomwalters@268 60 Whether the flag is strict or lenient, all illegal sequences will cause
tomwalters@268 61 an error return. This includes sequences such as: <F4 90 80 80>, <C0 80>,
tomwalters@268 62 or <A0> in UTF-8, and values above 0x10FFFF in UTF-32. Conformant code
tomwalters@268 63 must check for illegal sequences.
tomwalters@268 64
tomwalters@268 65 When the flag is set to lenient, characters over 0x10FFFF are converted
tomwalters@268 66 to the replacement character; otherwise (when the flag is set to strict)
tomwalters@268 67 they constitute an error.
tomwalters@268 68
tomwalters@268 69 Output parameters:
tomwalters@268 70 The value "sourceIllegal" is returned from some routines if the input
tomwalters@268 71 sequence is malformed. When "sourceIllegal" is returned, the source
tomwalters@268 72 value will point to the illegal value that caused the problem. E.g.,
tomwalters@268 73 in UTF-8 when a sequence is malformed, it points to the start of the
tomwalters@268 74 malformed sequence.
tomwalters@268 75
tomwalters@268 76 Author: Mark E. Davis, 1994.
tomwalters@268 77 Rev History: Rick McGowan, fixes & updates May 2001.
tomwalters@268 78 Fixes & updates, Sept 2001.
tomwalters@268 79
tomwalters@268 80 ------------------------------------------------------------------------ */
tomwalters@268 81
tomwalters@268 82 /* ---------------------------------------------------------------------
tomwalters@268 83 The following 4 definitions are compiler-specific.
tomwalters@268 84 The C standard does not guarantee that wchar_t has at least
tomwalters@268 85 16 bits, so wchar_t is no less portable than unsigned short!
tomwalters@268 86 All should be unsigned values to avoid sign extension during
tomwalters@268 87 bit mask & shift operations.
tomwalters@268 88 ------------------------------------------------------------------------ */
tomwalters@268 89
tomwalters@268 90 typedef unsigned int UTF32; /* at least 32 bits */
tomwalters@268 91 typedef unsigned short UTF16; /* at least 16 bits */
tomwalters@268 92 typedef unsigned char UTF8; /* typically 8 bits */
tomwalters@268 93 typedef unsigned char Boolean; /* 0 or 1 */
tomwalters@268 94
tomwalters@268 95 /* Some fundamental constants */
tomwalters@268 96 #define UNI_REPLACEMENT_CHAR (UTF32)0x0000FFFD
tomwalters@268 97 #define UNI_MAX_BMP (UTF32)0x0000FFFF
tomwalters@268 98 #define UNI_MAX_UTF16 (UTF32)0x0010FFFF
tomwalters@268 99 #define UNI_MAX_UTF32 (UTF32)0x7FFFFFFF
tomwalters@268 100 #define UNI_MAX_LEGAL_UTF32 (UTF32)0x0010FFFF
tomwalters@268 101
tomwalters@268 102 typedef enum {
tomwalters@268 103 conversionOK, /* conversion successful */
tomwalters@268 104 sourceExhausted, /* partial character in source, but hit end */
tomwalters@268 105 targetExhausted, /* insuff. room in target for conversion */
tomwalters@268 106 sourceIllegal /* source sequence is illegal/malformed */
tomwalters@268 107 } ConversionResult;
tomwalters@268 108
tomwalters@268 109 typedef enum {
tomwalters@268 110 strictConversion = 0,
tomwalters@268 111 lenientConversion
tomwalters@268 112 } ConversionFlags;
tomwalters@268 113
tomwalters@268 114 /* This is for C++ and does no harm in C */
tomwalters@268 115 #ifdef __cplusplus
tomwalters@268 116 extern "C" {
tomwalters@268 117 #endif
tomwalters@268 118
tomwalters@268 119 ConversionResult ConvertUTF8toUTF16 (
tomwalters@268 120 const UTF8** sourceStart, const UTF8* sourceEnd,
tomwalters@268 121 UTF16** targetStart, UTF16* targetEnd, ConversionFlags flags);
tomwalters@268 122
tomwalters@268 123 ConversionResult ConvertUTF16toUTF8 (
tomwalters@268 124 const UTF16** sourceStart, const UTF16* sourceEnd,
tomwalters@268 125 UTF8** targetStart, UTF8* targetEnd, ConversionFlags flags);
tomwalters@268 126
tomwalters@268 127 ConversionResult ConvertUTF8toUTF32 (
tomwalters@268 128 const UTF8** sourceStart, const UTF8* sourceEnd,
tomwalters@268 129 UTF32** targetStart, UTF32* targetEnd, ConversionFlags flags);
tomwalters@268 130
tomwalters@268 131 ConversionResult ConvertUTF32toUTF8 (
tomwalters@268 132 const UTF32** sourceStart, const UTF32* sourceEnd,
tomwalters@268 133 UTF8** targetStart, UTF8* targetEnd, ConversionFlags flags);
tomwalters@268 134
tomwalters@268 135 ConversionResult ConvertUTF16toUTF32 (
tomwalters@268 136 const UTF16** sourceStart, const UTF16* sourceEnd,
tomwalters@268 137 UTF32** targetStart, UTF32* targetEnd, ConversionFlags flags);
tomwalters@268 138
tomwalters@268 139 ConversionResult ConvertUTF32toUTF16 (
tomwalters@268 140 const UTF32** sourceStart, const UTF32* sourceEnd,
tomwalters@268 141 UTF16** targetStart, UTF16* targetEnd, ConversionFlags flags);
tomwalters@268 142
tomwalters@268 143 Boolean isLegalUTF8Sequence(const UTF8 *source, const UTF8 *sourceEnd);
tomwalters@268 144
tomwalters@268 145 #ifdef __cplusplus
tomwalters@268 146 }
tomwalters@268 147 #endif
tomwalters@268 148
tomwalters@268 149 /* --------------------------------------------------------------------- */