1 1ac119fb 2024-01-23 op /* Copyright (c) 2008-2009 Bjoern Hoehrmann <bjoern@hoehrmann.de>
  2 1ac119fb 2024-01-23 op  *
  3 1ac119fb 2024-01-23 op  * Permission is hereby granted, free of charge, to any person
  4 1ac119fb 2024-01-23 op  * obtaining a copy of this software and associated documentation
  5 1ac119fb 2024-01-23 op  * files (the "Software"), to deal in the Software without
  6 1ac119fb 2024-01-23 op  * restriction, including without limitation the rights to use, copy,
  7 1ac119fb 2024-01-23 op  * modify, merge, publish, distribute, sublicense, and/or sell copies
  8 1ac119fb 2024-01-23 op  * of the Software, and to permit persons to whom the Software is
  9 1ac119fb 2024-01-23 op  * furnished to do so, subject to the following conditions:
 10 1ac119fb 2024-01-23 op  *
 11 1ac119fb 2024-01-23 op  * The above copyright notice and this permission notice shall be
 12 1ac119fb 2024-01-23 op  * included in all copies or substantial portions of the Software.
 13 1ac119fb 2024-01-23 op  *
 14 1ac119fb 2024-01-23 op  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 15 1ac119fb 2024-01-23 op  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 16 1ac119fb 2024-01-23 op  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 17 1ac119fb 2024-01-23 op  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 18 1ac119fb 2024-01-23 op  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 19 1ac119fb 2024-01-23 op  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 20 1ac119fb 2024-01-23 op  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 21 1ac119fb 2024-01-23 op  * SOFTWARE.
 22 1ac119fb 2024-01-23 op  */
 23 1ac119fb 2024-01-23 op 
 24 1ac119fb 2024-01-23 op #include "compat.h"
 25 1ac119fb 2024-01-23 op 
 26 1ac119fb 2024-01-23 op #include <assert.h>
 27 1ac119fb 2024-01-23 op #include <stddef.h>
 28 1ac119fb 2024-01-23 op #include <stdint.h>
 29 1ac119fb 2024-01-23 op #include <wchar.h>
 30 1ac119fb 2024-01-23 op 
 31 1ac119fb 2024-01-23 op #include "utf8.h"
 32 1ac119fb 2024-01-23 op 
 33 1ac119fb 2024-01-23 op #define UTF8_ACCEPT 0
 34 1ac119fb 2024-01-23 op #define UTF8_REJECT 1
 35 1ac119fb 2024-01-23 op 
 36 1ac119fb 2024-01-23 op static const uint8_t utf8d[] = {
 37 1ac119fb 2024-01-23 op 	0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, // 00..1f
 38 1ac119fb 2024-01-23 op 	0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, // 20..3f
 39 1ac119fb 2024-01-23 op 	0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, // 40..5f
 40 1ac119fb 2024-01-23 op 	0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, // 60..7f
 41 1ac119fb 2024-01-23 op 	1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9, // 80..9f
 42 1ac119fb 2024-01-23 op 	7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7, // a0..bf
 43 1ac119fb 2024-01-23 op 	8,8,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2, // c0..df
 44 1ac119fb 2024-01-23 op 	0xa,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x4,0x3,0x3, // e0..ef
 45 1ac119fb 2024-01-23 op 	0xb,0x6,0x6,0x6,0x5,0x8,0x8,0x8,0x8,0x8,0x8,0x8,0x8,0x8,0x8,0x8, // f0..ff
 46 1ac119fb 2024-01-23 op 	0x0,0x1,0x2,0x3,0x5,0x8,0x7,0x1,0x1,0x1,0x4,0x6,0x1,0x1,0x1,0x1, // s0..s0
 47 1ac119fb 2024-01-23 op 	1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,0,1,1,1,1,1,0,1,0,1,1,1,1,1,1, // s1..s2
 48 1ac119fb 2024-01-23 op 	1,2,1,1,1,1,1,2,1,2,1,1,1,1,1,1,1,1,1,1,1,1,1,2,1,1,1,1,1,1,1,1, // s3..s4
 49 1ac119fb 2024-01-23 op 	1,2,1,1,1,1,1,1,1,2,1,1,1,1,1,1,1,1,1,1,1,1,1,3,1,3,1,1,1,1,1,1, // s5..s6
 50 1ac119fb 2024-01-23 op 	1,3,1,1,1,1,1,3,1,3,1,1,1,1,1,1,1,3,1,1,1,1,1,1,1,1,1,1,1,1,1,1, // s7..s8
 51 1ac119fb 2024-01-23 op };
 52 1ac119fb 2024-01-23 op 
 53 1ac119fb 2024-01-23 op static inline uint32_t
 54 1ac119fb 2024-01-23 op decode(uint32_t* restrict state, uint32_t* restrict codep, uint8_t byte)
 55 1ac119fb 2024-01-23 op {
 56 1ac119fb 2024-01-23 op 	uint32_t type = utf8d[byte];
 57 1ac119fb 2024-01-23 op 
 58 1ac119fb 2024-01-23 op 	*codep = (*state != UTF8_ACCEPT) ?
 59 1ac119fb 2024-01-23 op 		(byte & 0x3fu) | (*codep << 6) :
 60 1ac119fb 2024-01-23 op 		(0xff >> type) & (byte);
 61 1ac119fb 2024-01-23 op 
 62 1ac119fb 2024-01-23 op 	*state = utf8d[256 + *state*16 + type];
 63 1ac119fb 2024-01-23 op 	return *state;
 64 1ac119fb 2024-01-23 op }
 65 1ac119fb 2024-01-23 op 
 66 1ac119fb 2024-01-23 op 
 67 1ac119fb 2024-01-23 op /* end of the converter, utility functions ahead */
 68 1ac119fb 2024-01-23 op 
 69 1ac119fb 2024-01-23 op #define ZERO_WIDTH_SPACE 0x200B
 70 1ac119fb 2024-01-23 op 
 71 1ac119fb 2024-01-23 op /* public version of decode */
 72 1ac119fb 2024-01-23 op uint32_t
 73 1ac119fb 2024-01-23 op utf8_decode(uint32_t* restrict state, uint32_t* restrict codep, uint8_t byte)
 74 1ac119fb 2024-01-23 op {
 75 1ac119fb 2024-01-23 op 	return decode(state, codep, byte);
 76 1ac119fb 2024-01-23 op }
 77 1ac119fb 2024-01-23 op 
 78 f853ec6f 2024-10-22 op /*
 79 f853ec6f 2024-10-22 op  * returns 0, 1, 2 or less than 8 for tabs.  assumes that
 80 f853ec6f 2024-10-22 op  * sizeof(wchar_t) == 4
 81 f853ec6f 2024-10-22 op  */
 82 613281e4 2024-10-20 op static size_t
 83 f853ec6f 2024-10-22 op utf8_chwidth(uint32_t cp, int col)
 84 1ac119fb 2024-01-23 op {
 85 1ac119fb 2024-01-23 op 	/* XXX: if we're running on a platform where sizeof(wchar_t)
 86 1ac119fb 2024-01-23 op 	 * == 2 what to do?  The manpage for wcwidth and wcs isn't
 87 1ac119fb 2024-01-23 op 	 * clear about the encoding, but if it's 16 bit wide I assume
 88 1ac119fb 2024-01-23 op 	 * it must use UTF-16... right? */
 89 1ac119fb 2024-01-23 op 	assert(sizeof(wchar_t) == 4);
 90 1ac119fb 2024-01-23 op 
 91 1ac119fb 2024-01-23 op 	/*
 92 f853ec6f 2024-10-22 op 	 * Tabs are wide until the next multiple of eight.
 93 1ac119fb 2024-01-23 op 	 */
 94 1ac119fb 2024-01-23 op 	if (cp == '\t')
 95 f853ec6f 2024-10-22 op 		return (((col + 8) / 8) * 8) - col;
 96 1ac119fb 2024-01-23 op 
 97 1ac119fb 2024-01-23 op 	return wcwidth((wchar_t)cp);
 98 1ac119fb 2024-01-23 op }
 99 1ac119fb 2024-01-23 op 
100 1ac119fb 2024-01-23 op size_t
101 f853ec6f 2024-10-22 op utf8_snwidth(const char *s, size_t off, int col)
102 1ac119fb 2024-01-23 op {
103 1ac119fb 2024-01-23 op 	size_t i, tot;
104 1ac119fb 2024-01-23 op 	uint32_t cp = 0, state = 0;
105 f853ec6f 2024-10-22 op 	int width;
106 1ac119fb 2024-01-23 op 
107 1ac119fb 2024-01-23 op 	tot = 0;
108 6d24bfb3 2024-10-19 op 	for (i = 0; i < off; ++i)
109 f853ec6f 2024-10-22 op 		if (!decode(&state, &cp, s[i])) {
110 f853ec6f 2024-10-22 op 			width = utf8_chwidth(cp, col);
111 f853ec6f 2024-10-22 op 			tot += width;
112 f853ec6f 2024-10-22 op 			col += width;
113 f853ec6f 2024-10-22 op 		}
114 1ac119fb 2024-01-23 op 
115 1ac119fb 2024-01-23 op 	return tot;
116 1ac119fb 2024-01-23 op }
117 1ac119fb 2024-01-23 op 
118 1ac119fb 2024-01-23 op size_t
119 f853ec6f 2024-10-22 op utf8_swidth(const char *s, int col )
120 1ac119fb 2024-01-23 op {
121 1ac119fb 2024-01-23 op 	size_t tot;
122 1ac119fb 2024-01-23 op 	uint32_t cp = 0, state = 0;
123 f853ec6f 2024-10-22 op 	int width;
124 1ac119fb 2024-01-23 op 
125 1ac119fb 2024-01-23 op 	tot = 0;
126 1ac119fb 2024-01-23 op 	for (; *s; ++s)
127 f853ec6f 2024-10-22 op 		if (!decode(&state, &cp, *s)) {
128 f853ec6f 2024-10-22 op 			width = utf8_chwidth(cp, col);
129 f853ec6f 2024-10-22 op 			tot += width;
130 f853ec6f 2024-10-22 op 			col += width;
131 f853ec6f 2024-10-22 op 		}
132 1ac119fb 2024-01-23 op 
133 1ac119fb 2024-01-23 op 	return tot;
134 1ac119fb 2024-01-23 op }
135 1ac119fb 2024-01-23 op 
136 1ac119fb 2024-01-23 op size_t
137 f853ec6f 2024-10-22 op utf8_swidth_between(const char *str, const char *end, int col)
138 1ac119fb 2024-01-23 op {
139 1ac119fb 2024-01-23 op 	size_t tot;
140 1ac119fb 2024-01-23 op 	uint32_t cp = 0, state = 0;
141 f853ec6f 2024-10-22 op 	int width;
142 1ac119fb 2024-01-23 op 
143 1ac119fb 2024-01-23 op 	tot = 0;
144 1ac119fb 2024-01-23 op 	for (; *str && str < end; ++str)
145 f853ec6f 2024-10-22 op 		if (!decode(&state, &cp, *str)) {
146 f853ec6f 2024-10-22 op 			width = utf8_chwidth(cp, col);
147 f853ec6f 2024-10-22 op 			tot += width;
148 f853ec6f 2024-10-22 op 			col += width;
149 f853ec6f 2024-10-22 op 		}
150 1ac119fb 2024-01-23 op 	return tot;
151 1ac119fb 2024-01-23 op }
152 1ac119fb 2024-01-23 op 
153 1ac119fb 2024-01-23 op /*
154 1ac119fb 2024-01-23 op  * XXX: This is not correct.  There are codepoints classified as
155 2815e3a0 2024-09-01 op  * "emoji", but these can be joined together to form more complex
156 1ac119fb 2024-01-23 op  * emoji.  There is an official list of what these valid combinations
157 1ac119fb 2024-01-23 op  * are, but it would require a costly lookup (a trie can be used to
158 1ac119fb 2024-01-23 op  * reduce the times, but...).  The following approach is conceptually
159 1ac119fb 2024-01-23 op  * simpler: if there is a sequence of "emoji codepoints" (or ZWS) and
160 1ac119fb 2024-01-23 op  * then a space, consider everything before the space a single emoji.
161 1ac119fb 2024-01-23 op  * It needs a special check for numbers (yes, 0..9 and # are
162 1ac119fb 2024-01-23 op  * technically speaking emojis) but otherwise seems to work well in
163 1ac119fb 2024-01-23 op  * practice.
164 1ac119fb 2024-01-23 op  */
165 1ac119fb 2024-01-23 op int
166 1ac119fb 2024-01-23 op emojied_line(const char *s, const char **space_ret)
167 1ac119fb 2024-01-23 op {
168 1ac119fb 2024-01-23 op 	uint32_t cp = 0, state = 0;
169 1ac119fb 2024-01-23 op 	int only_numbers = 1;
170 1ac119fb 2024-01-23 op 
171 1ac119fb 2024-01-23 op 	for (; *s; ++s) {
172 1ac119fb 2024-01-23 op 		if (!decode(&state, &cp, *s)) {
173 1ac119fb 2024-01-23 op 			if (cp == ZERO_WIDTH_SPACE)
174 1ac119fb 2024-01-23 op 				continue;
175 1ac119fb 2024-01-23 op 			if (cp == ' ') {
176 1ac119fb 2024-01-23 op 				*space_ret = s;
177 1ac119fb 2024-01-23 op 				return !only_numbers;
178 1ac119fb 2024-01-23 op 			}
179 1ac119fb 2024-01-23 op 			if (!is_emoji(cp))
180 1ac119fb 2024-01-23 op 				return 0;
181 1ac119fb 2024-01-23 op 			if (cp < '0' || cp > '9')
182 1ac119fb 2024-01-23 op 				only_numbers = 0;
183 1ac119fb 2024-01-23 op 		}
184 1ac119fb 2024-01-23 op 	}
185 1ac119fb 2024-01-23 op 
186 1ac119fb 2024-01-23 op 	return 0;
187 1ac119fb 2024-01-23 op }