| 1 | |
| 2 | |
| 3 | * Copyright (c) 2014 SGI.
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| 4 | * All rights reserved.
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| 5 |
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| 6 |
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| 7 | #include "utf8n.h"
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| 8 |
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| 9 | int utf8version_is_supported(const struct unicode_map *um, unsigned int version)
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| 10 | {
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| 11 | int i = um->tables->utf8agetab_size - 1;
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| 12 |
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| 13 | while (i >= 0 && um->tables->utf8agetab[i] != 0) {
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| 14 | if (version == um->tables->utf8agetab[i])
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| 15 | return 1;
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| 16 | i--;
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| 17 | }
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| 18 | return 0;
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| 19 | }
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| 20 |
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| 21 | |
| 22 | * UTF-8 valid ranges.
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| 23 | *
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| 24 | * The UTF-8 encoding spreads the bits of a 32bit word over several
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| 25 | * bytes. This table gives the ranges that can be held and how they'd
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| 26 | * be represented.
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| 27 | *
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| 28 | * 0x00000000 0x0000007F: 0xxxxxxx
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| 29 | * 0x00000000 0x000007FF: 110xxxxx 10xxxxxx
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| 30 | * 0x00000000 0x0000FFFF: 1110xxxx 10xxxxxx 10xxxxxx
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| 31 | * 0x00000000 0x001FFFFF: 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
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| 32 | * 0x00000000 0x03FFFFFF: 111110xx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx
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| 33 | * 0x00000000 0x7FFFFFFF: 1111110x 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx
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| 34 | *
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| 35 | * There is an additional requirement on UTF-8, in that only the
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| 36 | * shortest representation of a 32bit value is to be used. A decoder
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| 37 | * must not decode sequences that do not satisfy this requirement.
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| 38 | * Thus the allowed ranges have a lower bound.
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| 39 | *
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| 40 | * 0x00000000 0x0000007F: 0xxxxxxx
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| 41 | * 0x00000080 0x000007FF: 110xxxxx 10xxxxxx
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| 42 | * 0x00000800 0x0000FFFF: 1110xxxx 10xxxxxx 10xxxxxx
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| 43 | * 0x00010000 0x001FFFFF: 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
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| 44 | * 0x00200000 0x03FFFFFF: 111110xx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx
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| 45 | * 0x04000000 0x7FFFFFFF: 1111110x 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx
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| 46 | *
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| 47 | * Actual unicode characters are limited to the range 0x0 - 0x10FFFF,
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| 48 | * 17 planes of 65536 values. This limits the sequences actually seen
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| 49 | * even more, to just the following.
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| 50 | *
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| 51 | * 0 - 0x7F: 0 - 0x7F
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| 52 | * 0x80 - 0x7FF: 0xC2 0x80 - 0xDF 0xBF
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| 53 | * 0x800 - 0xFFFF: 0xE0 0xA0 0x80 - 0xEF 0xBF 0xBF
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| 54 | * 0x10000 - 0x10FFFF: 0xF0 0x90 0x80 0x80 - 0xF4 0x8F 0xBF 0xBF
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| 55 | *
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| 56 | * Within those ranges the surrogates 0xD800 - 0xDFFF are not allowed.
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| 57 | *
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| 58 | * Note that the longest sequence seen with valid usage is 4 bytes,
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| 59 | * the same a single UTF-32 character. This makes the UTF-8
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| 60 | * representation of Unicode strictly smaller than UTF-32.
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| 61 | *
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| 62 | * The shortest sequence requirement was introduced by:
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| 63 | * Corrigendum #1: UTF-8 Shortest Form
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| 64 | * It can be found here:
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| 65 | * http://www.unicode.org/versions/corrigendum1.html
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| 66 | *
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| 67 |
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| 68 |
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| 69 | |
| 70 | * Return the number of bytes used by the current UTF-8 sequence.
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| 71 | * Assumes the input points to the first byte of a valid UTF-8
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| 72 | * sequence.
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| 73 |
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| 74 | static inline int utf8clen(const char *s)
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| 75 | {
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| 76 | unsigned char c = *s;
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| 77 |
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| 78 | return 1 + (c >= 0xC0) + (c >= 0xE0) + (c >= 0xF0);
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| 79 | }
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| 80 |
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| 81 | |
| 82 | * Decode a 3-byte UTF-8 sequence.
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| 83 |
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| 84 | static unsigned int
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| 85 | utf8decode3(const char *str)
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| 86 | {
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| 87 | unsigned int uc;
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| 88 |
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| 89 | uc = *str++ & 0x0F;
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| 90 | uc <<= 6;
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| 91 | uc |= *str++ & 0x3F;
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| 92 | uc <<= 6;
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| 93 | uc |= *str++ & 0x3F;
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| 94 |
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| 95 | return uc;
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| 96 | }
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| 97 |
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| 98 | |
| 99 | * Encode a 3-byte UTF-8 sequence.
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| 100 |
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| 101 | static int
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| 102 | utf8encode3(char *str, unsigned int val)
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| 103 | {
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| 104 | str[2] = (val & 0x3F) | 0x80;
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| 105 | val >>= 6;
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| 106 | str[1] = (val & 0x3F) | 0x80;
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| 107 | val >>= 6;
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| 108 | str[0] = val | 0xE0;
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| 109 |
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| 110 | return 3;
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| 111 | }
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| 112 |
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| 113 | |
| 114 | * utf8trie_t
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| 115 | *
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| 116 | * A compact binary tree, used to decode UTF-8 characters.
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| 117 | *
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| 118 | * Internal nodes are one byte for the node itself, and up to three
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| 119 | * bytes for an offset into the tree. The first byte contains the
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| 120 | * following information:
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| 121 | * NEXTBYTE - flag - advance to next byte if set
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| 122 | * BITNUM - 3 bit field - the bit number to tested
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| 123 | * OFFLEN - 2 bit field - number of bytes in the offset
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| 124 | * if offlen == 0 (non-branching node)
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| 125 | * RIGHTPATH - 1 bit field - set if the following node is for the
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| 126 | * right-hand path (tested bit is set)
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| 127 | * TRIENODE - 1 bit field - set if the following node is an internal
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| 128 | * node, otherwise it is a leaf node
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| 129 | * if offlen != 0 (branching node)
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| 130 | * LEFTNODE - 1 bit field - set if the left-hand node is internal
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| 131 | * RIGHTNODE - 1 bit field - set if the right-hand node is internal
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| 132 | *
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| 133 | * Due to the way utf8 works, there cannot be branching nodes with
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| 134 | * NEXTBYTE set, and moreover those nodes always have a righthand
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| 135 | * descendant.
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| 136 |
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| 137 | typedef const unsigned char utf8trie_t;
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| 138 | #define BITNUM 0x07
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| 139 | #define NEXTBYTE 0x08
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| 140 | #define OFFLEN 0x30
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| 141 | #define OFFLEN_SHIFT 4
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| 142 | #define RIGHTPATH 0x40
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| 143 | #define TRIENODE 0x80
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| 144 | #define RIGHTNODE 0x40
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| 145 | #define LEFTNODE 0x80
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| 146 |
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| 147 | |
| 148 | * utf8leaf_t
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| 149 | *
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| 150 | * The leaves of the trie are embedded in the trie, and so the same
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| 151 | * underlying datatype: unsigned char.
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| 152 | *
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| 153 | * leaf[0]: The unicode version, stored as a generation number that is
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| 154 | * an index into ->utf8agetab[]. With this we can filter code
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| 155 | * points based on the unicode version in which they were
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| 156 | * defined. The CCC of a non-defined code point is 0.
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| 157 | * leaf[1]: Canonical Combining Class. During normalization, we need
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| 158 | * to do a stable sort into ascending order of all characters
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| 159 | * with a non-zero CCC that occur between two characters with
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| 160 | * a CCC of 0, or at the begin or end of a string.
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| 161 | * The unicode standard guarantees that all CCC values are
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| 162 | * between 0 and 254 inclusive, which leaves 255 available as
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| 163 | * a special value.
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| 164 | * Code points with CCC 0 are known as stoppers.
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| 165 | * leaf[2]: Decomposition. If leaf[1] == 255, then leaf[2] is the
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| 166 | * start of a NUL-terminated string that is the decomposition
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| 167 | * of the character.
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| 168 | * The CCC of a decomposable character is the same as the CCC
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| 169 | * of the first character of its decomposition.
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| 170 | * Some characters decompose as the empty string: these are
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| 171 | * characters with the Default_Ignorable_Code_Point property.
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| 172 | * These do affect normalization, as they all have CCC 0.
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| 173 | *
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| 174 | * The decompositions in the trie have been fully expanded, with the
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| 175 | * exception of Hangul syllables, which are decomposed algorithmically.
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| 176 | *
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| 177 | * Casefolding, if applicable, is also done using decompositions.
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| 178 | *
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| 179 | * The trie is constructed in such a way that leaves exist for all
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| 180 | * UTF-8 sequences that match the criteria from the "UTF-8 valid
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| 181 | * ranges" comment above, and only for those sequences. Therefore a
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| 182 | * lookup in the trie can be used to validate the UTF-8 input.
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| 183 |
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| 184 | typedef const unsigned char utf8leaf_t;
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| 185 |
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| 186 | #define LEAF_GEN(LEAF) ((LEAF)[0])
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| 187 | #define LEAF_CCC(LEAF) ((LEAF)[1])
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| 188 | #define LEAF_STR(LEAF) ((const char *)((LEAF) + 2))
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| 189 |
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| 190 | #define MINCCC (0)
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| 191 | #define MAXCCC (254)
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| 192 | #define STOPPER (0)
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| 193 | #define DECOMPOSE (255)
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| 194 |
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| 195 |
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| 196 | #define HANGUL ((char)(255))
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| 197 |
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| 198 | #define UTF8HANGULLEAF (12)
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| 199 |
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| 200 | |
| 201 | * Hangul decomposition (algorithm from Section 3.12 of Unicode 6.3.0)
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| 202 | *
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| 203 | * AC00;<Hangul Syllable, First>;Lo;0;L;;;;;N;;;;;
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| 204 | * D7A3;<Hangul Syllable, Last>;Lo;0;L;;;;;N;;;;;
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| 205 | *
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| 206 | * SBase = 0xAC00
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| 207 | * LBase = 0x1100
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| 208 | * VBase = 0x1161
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| 209 | * TBase = 0x11A7
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| 210 | * LCount = 19
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| 211 | * VCount = 21
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| 212 | * TCount = 28
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| 213 | * NCount = 588 (VCount * TCount)
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| 214 | * SCount = 11172 (LCount * NCount)
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| 215 | *
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| 216 | * Decomposition:
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| 217 | * SIndex = s - SBase
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| 218 | *
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| 219 | * LV (Canonical/Full)
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| 220 | * LIndex = SIndex / NCount
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| 221 | * VIndex = (Sindex % NCount) / TCount
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| 222 | * LPart = LBase + LIndex
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| 223 | * VPart = VBase + VIndex
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| 224 | *
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| 225 | * LVT (Canonical)
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| 226 | * LVIndex = (SIndex / TCount) * TCount
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| 227 | * TIndex = (Sindex % TCount)
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| 228 | * LVPart = SBase + LVIndex
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| 229 | * TPart = TBase + TIndex
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| 230 | *
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| 231 | * LVT (Full)
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| 232 | * LIndex = SIndex / NCount
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| 233 | * VIndex = (Sindex % NCount) / TCount
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| 234 | * TIndex = (Sindex % TCount)
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| 235 | * LPart = LBase + LIndex
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| 236 | * VPart = VBase + VIndex
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| 237 | * if (TIndex == 0) {
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| 238 | * d = <LPart, VPart>
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| 239 | * } else {
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| 240 | * TPart = TBase + TIndex
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| 241 | * d = <LPart, TPart, VPart>
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| 242 | * }
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| 243 |
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| 244 |
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| 245 |
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| 246 | #define SB (0xAC00)
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| 247 | #define LB (0x1100)
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| 248 | #define VB (0x1161)
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| 249 | #define TB (0x11A7)
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| 250 | #define LC (19)
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| 251 | #define VC (21)
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| 252 | #define TC (28)
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| 253 | #define NC (VC * TC)
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| 254 | #define SC (LC * NC)
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| 255 |
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| 256 |
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| 257 | static utf8leaf_t *
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| 258 | utf8hangul(const char *str, unsigned char *hangul)
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| 259 | {
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| 260 | unsigned int si;
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| 261 | unsigned int li;
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| 262 | unsigned int vi;
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| 263 | unsigned int ti;
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| 264 | unsigned char *h;
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| 265 |
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| 266 |
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| 267 | si = utf8decode3(str) - SB;
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| 268 | li = si / NC;
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| 269 | vi = (si % NC) / TC;
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| 270 | ti = si % TC;
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| 271 |
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| 272 |
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| 273 | h = hangul;
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| 274 | LEAF_GEN(h) = 2;
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| 275 | LEAF_CCC(h) = DECOMPOSE;
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| 276 | h += 2;
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| 277 |
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| 278 |
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| 279 | h += utf8encode3((char *)h, li + LB);
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| 280 |
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| 281 |
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| 282 | h += utf8encode3((char *)h, vi + VB);
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| 283 |
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| 284 |
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| 285 | if (ti)
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| 286 | h += utf8encode3((char *)h, ti + TB);
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| 287 |
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| 288 |
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| 289 | h[0] = '\0';
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| 290 |
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| 291 | return hangul;
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| 292 | }
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| 293 |
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| 294 | |
| 295 | * Use trie to scan s, touching at most len bytes.
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| 296 | * Returns the leaf if one exists, NULL otherwise.
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| 297 | *
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| 298 | * A non-NULL return guarantees that the UTF-8 sequence starting at s
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| 299 | * is well-formed and corresponds to a known unicode code point. The
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| 300 | * shorthand for this will be "is valid UTF-8 unicode".
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| 301 |
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| 302 | static utf8leaf_t *utf8nlookup(const struct unicode_map *um,
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| 303 | enum utf8_normalization n, unsigned char *hangul, const char *s,
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| 304 | size_t len)
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| 305 | {
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| 306 | utf8trie_t *trie = um->tables->utf8data + um->ntab[n]->offset;
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| 307 | int offlen;
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| 308 | int offset;
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| 309 | int mask;
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| 310 | int node;
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| 311 |
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| 312 | if (len == 0)
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| 313 | return NULL;
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| 314 |
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| 315 | node = 1;
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| 316 | while (node) {
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| 317 | offlen = (*trie & OFFLEN) >> OFFLEN_SHIFT;
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| 318 | if (*trie & NEXTBYTE) {
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| 319 | if (--len == 0)
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| 320 | return NULL;
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| 321 | s++;
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| 322 | }
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| 323 | mask = 1 << (*trie & BITNUM);
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| 324 | if (*s & mask) {
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| 325 |
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| 326 | if (offlen) {
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| 327 |
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| 328 | node = (*trie & RIGHTNODE);
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| 329 | offset = trie[offlen];
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| 330 | while (--offlen) {
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| 331 | offset <<= 8;
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| 332 | offset |= trie[offlen];
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| 333 | }
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| 334 | trie += offset;
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| 335 | } else if (*trie & RIGHTPATH) {
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| 336 |
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| 337 | node = (*trie & TRIENODE);
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| 338 | trie++;
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| 339 | } else {
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| 340 |
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| 341 | return NULL;
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| 342 | }
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| 343 | } else {
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| 344 |
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| 345 | if (offlen) {
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| 346 |
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| 347 | node = (*trie & LEFTNODE);
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| 348 | trie += offlen + 1;
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| 349 | } else if (*trie & RIGHTPATH) {
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| 350 |
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| 351 | return NULL;
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| 352 | } else {
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| 353 |
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| 354 | node = (*trie & TRIENODE);
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| 355 | trie++;
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| 356 | }
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| 357 | }
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| 358 | }
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| 359 | |
| 360 | * Hangul decomposition is done algorithmically. These are the
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| 361 | * codepoints >= 0xAC00 and <= 0xD7A3. Their UTF-8 encoding is
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| 362 | * always 3 bytes long, so s has been advanced twice, and the
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| 363 | * start of the sequence is at s-2.
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| 364 |
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| 365 | if (LEAF_CCC(trie) == DECOMPOSE && LEAF_STR(trie)[0] == HANGUL)
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| 366 | trie = utf8hangul(s - 2, hangul);
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| 367 | return trie;
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| 368 | }
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| 369 |
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| 370 | |
| 371 | * Use trie to scan s.
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| 372 | * Returns the leaf if one exists, NULL otherwise.
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| 373 | *
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| 374 | * Forwards to utf8nlookup().
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| 375 |
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| 376 | static utf8leaf_t *utf8lookup(const struct unicode_map *um,
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| 377 | enum utf8_normalization n, unsigned char *hangul, const char *s)
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| 378 | {
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| 379 | return utf8nlookup(um, n, hangul, s, (size_t)-1);
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| 380 | }
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| 381 |
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| 382 | |
| 383 | * Length of the normalization of s, touch at most len bytes.
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| 384 | * Return -1 if s is not valid UTF-8 unicode.
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| 385 |
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| 386 | ssize_t utf8nlen(const struct unicode_map *um, enum utf8_normalization n,
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| 387 | const char *s, size_t len)
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| 388 | {
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| 389 | utf8leaf_t *leaf;
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| 390 | size_t ret = 0;
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| 391 | unsigned char hangul[UTF8HANGULLEAF];
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| 392 |
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| 393 | while (len && *s) {
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| 394 | leaf = utf8nlookup(um, n, hangul, s, len);
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| 395 | if (!leaf)
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| 396 | return -1;
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| 397 | if (um->tables->utf8agetab[LEAF_GEN(leaf)] >
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| 398 | um->ntab[n]->maxage)
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| 399 | ret += utf8clen(s);
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| 400 | else if (LEAF_CCC(leaf) == DECOMPOSE)
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| 401 | ret += strlen(LEAF_STR(leaf));
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| 402 | else
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| 403 | ret += utf8clen(s);
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| 404 | len -= utf8clen(s);
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| 405 | s += utf8clen(s);
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| 406 | }
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| 407 | return ret;
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| 408 | }
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| 409 |
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| 410 | |
| 411 | * Set up an utf8cursor for use by utf8byte().
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| 412 | *
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| 413 | * u8c : pointer to cursor.
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| 414 | * data : const struct utf8data to use for normalization.
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| 415 | * s : string.
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| 416 | * len : length of s.
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| 417 | *
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| 418 | * Returns -1 on error, 0 on success.
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| 419 |
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| 420 | int utf8ncursor(struct utf8cursor *u8c, const struct unicode_map *um,
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| 421 | enum utf8_normalization n, const char *s, size_t len)
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| 422 | {
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| 423 | if (!s)
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| 424 | return -1;
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| 425 | u8c->um = um;
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| 426 | u8c->n = n;
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| 427 | u8c->s = s;
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| 428 | u8c->p = NULL;
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| 429 | u8c->ss = NULL;
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| 430 | u8c->sp = NULL;
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| 431 | u8c->len = len;
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| 432 | u8c->slen = 0;
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| 433 | u8c->ccc = STOPPER;
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| 434 | u8c->nccc = STOPPER;
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| 435 |
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| 436 | if (u8c->len != len)
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| 437 | return -1;
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| 438 |
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| 439 | if (len > 0 && (*s & 0xC0) == 0x80)
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| 440 | return -1;
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| 441 | return 0;
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| 442 | }
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| 443 |
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| 444 | |
| 445 | * Get one byte from the normalized form of the string described by u8c.
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| 446 | *
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| 447 | * Returns the byte cast to an unsigned char on succes, and -1 on failure.
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| 448 | *
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| 449 | * The cursor keeps track of the location in the string in u8c->s.
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| 450 | * When a character is decomposed, the current location is stored in
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| 451 | * u8c->p, and u8c->s is set to the start of the decomposition. Note
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| 452 | * that bytes from a decomposition do not count against u8c->len.
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| 453 | *
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| 454 | * Characters are emitted if they match the current CCC in u8c->ccc.
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| 455 | * Hitting end-of-string while u8c->ccc == STOPPER means we're done,
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| 456 | * and the function returns 0 in that case.
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| 457 | *
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| 458 | * Sorting by CCC is done by repeatedly scanning the string. The
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| 459 | * values of u8c->s and u8c->p are stored in u8c->ss and u8c->sp at
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| 460 | * the start of the scan. The first pass finds the lowest CCC to be
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| 461 | * emitted and stores it in u8c->nccc, the second pass emits the
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| 462 | * characters with this CCC and finds the next lowest CCC. This limits
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| 463 | * the number of passes to 1 + the number of different CCCs in the
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| 464 | * sequence being scanned.
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| 465 | *
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| 466 | * Therefore:
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| 467 | * u8c->p != NULL -> a decomposition is being scanned.
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| 468 | * u8c->ss != NULL -> this is a repeating scan.
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| 469 | * u8c->ccc == -1 -> this is the first scan of a repeating scan.
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| 470 |
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| 471 | int utf8byte(struct utf8cursor *u8c)
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| 472 | {
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| 473 | utf8leaf_t *leaf;
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| 474 | int ccc;
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| 475 |
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| 476 | for (;;) {
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| 477 |
|
| 478 | if (u8c->p && *u8c->s == '\0') {
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| 479 | u8c->s = u8c->p;
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| 480 | u8c->p = NULL;
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| 481 | }
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| 482 |
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| 483 |
|
| 484 | if (!u8c->p && (u8c->len == 0 || *u8c->s == '\0')) {
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| 485 |
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| 486 | if (u8c->ccc == STOPPER)
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| 487 | return 0;
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| 488 |
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| 489 | ccc = STOPPER;
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| 490 | goto ccc_mismatch;
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| 491 | } else if ((*u8c->s & 0xC0) == 0x80) {
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| 492 |
|
| 493 | if (!u8c->p)
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| 494 | u8c->len--;
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| 495 | return (unsigned char)*u8c->s++;
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| 496 | }
|
| 497 |
|
| 498 |
|
| 499 | if (u8c->p) {
|
| 500 | leaf = utf8lookup(u8c->um, u8c->n, u8c->hangul, u8c->s);
|
| 501 | } else {
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| 502 | leaf = utf8nlookup(u8c->um, u8c->n, u8c->hangul,
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| 503 | u8c->s, u8c->len);
|
| 504 | }
|
| 505 |
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| 506 |
|
| 507 | if (!leaf)
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| 508 | return -1;
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| 509 |
|
| 510 | ccc = LEAF_CCC(leaf);
|
| 511 |
|
| 512 | if (u8c->um->tables->utf8agetab[LEAF_GEN(leaf)] >
|
| 513 | u8c->um->ntab[u8c->n]->maxage) {
|
| 514 | ccc = STOPPER;
|
| 515 | } else if (ccc == DECOMPOSE) {
|
| 516 | u8c->len -= utf8clen(u8c->s);
|
| 517 | u8c->p = u8c->s + utf8clen(u8c->s);
|
| 518 | u8c->s = LEAF_STR(leaf);
|
| 519 |
|
| 520 | if (*u8c->s == '\0') {
|
| 521 | if (u8c->ccc == STOPPER)
|
| 522 | continue;
|
| 523 | ccc = STOPPER;
|
| 524 | goto ccc_mismatch;
|
| 525 | }
|
| 526 |
|
| 527 | leaf = utf8lookup(u8c->um, u8c->n, u8c->hangul, u8c->s);
|
| 528 | if (!leaf)
|
| 529 | return -1;
|
| 530 | ccc = LEAF_CCC(leaf);
|
| 531 | }
|
| 532 |
|
| 533 | |
| 534 | * If this is not a stopper, then see if it updates
|
| 535 | * the next canonical class to be emitted.
|
| 536 |
|
| 537 | if (ccc != STOPPER && u8c->ccc < ccc && ccc < u8c->nccc)
|
| 538 | u8c->nccc = ccc;
|
| 539 |
|
| 540 | |
| 541 | * Return the current byte if this is the current
|
| 542 | * combining class.
|
| 543 |
|
| 544 | if (ccc == u8c->ccc) {
|
| 545 | if (!u8c->p)
|
| 546 | u8c->len--;
|
| 547 | return (unsigned char)*u8c->s++;
|
| 548 | }
|
| 549 |
|
| 550 |
|
| 551 | ccc_mismatch:
|
| 552 | if (u8c->nccc == STOPPER) {
|
| 553 | |
| 554 | * Scan forward for the first canonical class
|
| 555 | * to be emitted. Save the position from
|
| 556 | * which to restart.
|
| 557 |
|
| 558 | u8c->ccc = MINCCC - 1;
|
| 559 | u8c->nccc = ccc;
|
| 560 | u8c->sp = u8c->p;
|
| 561 | u8c->ss = u8c->s;
|
| 562 | u8c->slen = u8c->len;
|
| 563 | if (!u8c->p)
|
| 564 | u8c->len -= utf8clen(u8c->s);
|
| 565 | u8c->s += utf8clen(u8c->s);
|
| 566 | } else if (ccc != STOPPER) {
|
| 567 |
|
| 568 | if (!u8c->p)
|
| 569 | u8c->len -= utf8clen(u8c->s);
|
| 570 | u8c->s += utf8clen(u8c->s);
|
| 571 | } else if (u8c->nccc != MAXCCC + 1) {
|
| 572 |
|
| 573 | u8c->ccc = u8c->nccc;
|
| 574 | u8c->nccc = MAXCCC + 1;
|
| 575 | u8c->s = u8c->ss;
|
| 576 | u8c->p = u8c->sp;
|
| 577 | u8c->len = u8c->slen;
|
| 578 | } else {
|
| 579 |
|
| 580 | u8c->ccc = STOPPER;
|
| 581 | u8c->nccc = STOPPER;
|
| 582 | u8c->sp = NULL;
|
| 583 | u8c->ss = NULL;
|
| 584 | u8c->slen = 0;
|
| 585 | }
|
| 586 | }
|
| 587 | }
|
| 588 |
|
| 589 | #if IS_MODULE(CONFIG_UNICODE_NORMALIZATION_KUNIT_TEST)
|
| 590 | EXPORT_SYMBOL_GPL(utf8version_is_supported);
|
| 591 | EXPORT_SYMBOL_GPL(utf8nlen);
|
| 592 | EXPORT_SYMBOL_GPL(utf8ncursor);
|
| 593 | EXPORT_SYMBOL_GPL(utf8byte);
|
| 594 | #endif
|