xref: /openbsd-src/usr.bin/tmux/utf8.c (revision 3d40d63a87e7d477e956d9dfca1e5d50688e719c) 
1 /* $OpenBSD: utf8.c,v 1.67 2025/01/01 15:17:36 nicm Exp $ */
2 
3 /*
4  * Copyright (c) 2008 Nicholas Marriott <nicholas.marriott@gmail.com>
5  *
6  * Permission to use, copy, modify, and distribute this software for any
7  * purpose with or without fee is hereby granted, provided that the above
8  * copyright notice and this permission notice appear in all copies.
9  *
10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14  * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER
15  * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
16  * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17  */
18 
19 #include <sys/types.h>
20 
21 #include <ctype.h>
22 #include <errno.h>
23 #include <stdlib.h>
24 #include <string.h>
25 #include <vis.h>
26 
27 #include "tmux.h"
28 
29 struct utf8_width_item {
30 	wchar_t				wc;
31 	u_int				width;
32 	int				allocated;
33 
34 	RB_ENTRY(utf8_width_item)	entry;
35 };
36 
37 static int
38 utf8_width_cache_cmp(struct utf8_width_item *uw1, struct utf8_width_item *uw2)
39 {
40 	if (uw1->wc < uw2->wc)
41 		return (-1);
42 	if (uw1->wc > uw2->wc)
43 		return (1);
44 	return (0);
45 }
46 RB_HEAD(utf8_width_cache, utf8_width_item);
47 RB_GENERATE_STATIC(utf8_width_cache, utf8_width_item, entry,
48     utf8_width_cache_cmp);
49 static struct utf8_width_cache utf8_width_cache =
50     RB_INITIALIZER(utf8_width_cache);
51 
52 static struct utf8_width_item utf8_default_width_cache[] = {
53 	{ .wc = 0x0261D, .width = 2 },
54 	{ .wc = 0x026F9, .width = 2 },
55 	{ .wc = 0x0270A, .width = 2 },
56 	{ .wc = 0x0270B, .width = 2 },
57 	{ .wc = 0x0270C, .width = 2 },
58 	{ .wc = 0x0270D, .width = 2 },
59 	{ .wc = 0x1F1E6, .width = 2 },
60 	{ .wc = 0x1F1E7, .width = 2 },
61 	{ .wc = 0x1F1E8, .width = 2 },
62 	{ .wc = 0x1F1E9, .width = 2 },
63 	{ .wc = 0x1F1EA, .width = 2 },
64 	{ .wc = 0x1F1EB, .width = 2 },
65 	{ .wc = 0x1F1EC, .width = 2 },
66 	{ .wc = 0x1F1ED, .width = 2 },
67 	{ .wc = 0x1F1EE, .width = 2 },
68 	{ .wc = 0x1F1EF, .width = 2 },
69 	{ .wc = 0x1F1F0, .width = 2 },
70 	{ .wc = 0x1F1F1, .width = 2 },
71 	{ .wc = 0x1F1F2, .width = 2 },
72 	{ .wc = 0x1F1F3, .width = 2 },
73 	{ .wc = 0x1F1F4, .width = 2 },
74 	{ .wc = 0x1F1F5, .width = 2 },
75 	{ .wc = 0x1F1F6, .width = 2 },
76 	{ .wc = 0x1F1F7, .width = 2 },
77 	{ .wc = 0x1F1F8, .width = 2 },
78 	{ .wc = 0x1F1F9, .width = 2 },
79 	{ .wc = 0x1F1FA, .width = 2 },
80 	{ .wc = 0x1F1FB, .width = 2 },
81 	{ .wc = 0x1F1FC, .width = 2 },
82 	{ .wc = 0x1F1FD, .width = 2 },
83 	{ .wc = 0x1F1FE, .width = 2 },
84 	{ .wc = 0x1F1FF, .width = 2 },
85 	{ .wc = 0x1F385, .width = 2 },
86 	{ .wc = 0x1F3C2, .width = 2 },
87 	{ .wc = 0x1F3C3, .width = 2 },
88 	{ .wc = 0x1F3C4, .width = 2 },
89 	{ .wc = 0x1F3C7, .width = 2 },
90 	{ .wc = 0x1F3CA, .width = 2 },
91 	{ .wc = 0x1F3CB, .width = 2 },
92 	{ .wc = 0x1F3CC, .width = 2 },
93 	{ .wc = 0x1F3FB, .width = 2 },
94 	{ .wc = 0x1F3FC, .width = 2 },
95 	{ .wc = 0x1F3FD, .width = 2 },
96 	{ .wc = 0x1F3FE, .width = 2 },
97 	{ .wc = 0x1F3FF, .width = 2 },
98 	{ .wc = 0x1F442, .width = 2 },
99 	{ .wc = 0x1F443, .width = 2 },
100 	{ .wc = 0x1F446, .width = 2 },
101 	{ .wc = 0x1F447, .width = 2 },
102 	{ .wc = 0x1F448, .width = 2 },
103 	{ .wc = 0x1F449, .width = 2 },
104 	{ .wc = 0x1F44A, .width = 2 },
105 	{ .wc = 0x1F44B, .width = 2 },
106 	{ .wc = 0x1F44C, .width = 2 },
107 	{ .wc = 0x1F44D, .width = 2 },
108 	{ .wc = 0x1F44E, .width = 2 },
109 	{ .wc = 0x1F44F, .width = 2 },
110 	{ .wc = 0x1F450, .width = 2 },
111 	{ .wc = 0x1F466, .width = 2 },
112 	{ .wc = 0x1F467, .width = 2 },
113 	{ .wc = 0x1F468, .width = 2 },
114 	{ .wc = 0x1F469, .width = 2 },
115 	{ .wc = 0x1F46B, .width = 2 },
116 	{ .wc = 0x1F46C, .width = 2 },
117 	{ .wc = 0x1F46D, .width = 2 },
118 	{ .wc = 0x1F46E, .width = 2 },
119 	{ .wc = 0x1F470, .width = 2 },
120 	{ .wc = 0x1F471, .width = 2 },
121 	{ .wc = 0x1F472, .width = 2 },
122 	{ .wc = 0x1F473, .width = 2 },
123 	{ .wc = 0x1F474, .width = 2 },
124 	{ .wc = 0x1F475, .width = 2 },
125 	{ .wc = 0x1F476, .width = 2 },
126 	{ .wc = 0x1F477, .width = 2 },
127 	{ .wc = 0x1F478, .width = 2 },
128 	{ .wc = 0x1F47C, .width = 2 },
129 	{ .wc = 0x1F481, .width = 2 },
130 	{ .wc = 0x1F482, .width = 2 },
131 	{ .wc = 0x1F483, .width = 2 },
132 	{ .wc = 0x1F485, .width = 2 },
133 	{ .wc = 0x1F486, .width = 2 },
134 	{ .wc = 0x1F487, .width = 2 },
135 	{ .wc = 0x1F48F, .width = 2 },
136 	{ .wc = 0x1F491, .width = 2 },
137 	{ .wc = 0x1F4AA, .width = 2 },
138 	{ .wc = 0x1F574, .width = 2 },
139 	{ .wc = 0x1F575, .width = 2 },
140 	{ .wc = 0x1F57A, .width = 2 },
141 	{ .wc = 0x1F590, .width = 2 },
142 	{ .wc = 0x1F595, .width = 2 },
143 	{ .wc = 0x1F596, .width = 2 },
144 	{ .wc = 0x1F645, .width = 2 },
145 	{ .wc = 0x1F646, .width = 2 },
146 	{ .wc = 0x1F647, .width = 2 },
147 	{ .wc = 0x1F64B, .width = 2 },
148 	{ .wc = 0x1F64C, .width = 2 },
149 	{ .wc = 0x1F64D, .width = 2 },
150 	{ .wc = 0x1F64E, .width = 2 },
151 	{ .wc = 0x1F64F, .width = 2 },
152 	{ .wc = 0x1F6A3, .width = 2 },
153 	{ .wc = 0x1F6B4, .width = 2 },
154 	{ .wc = 0x1F6B5, .width = 2 },
155 	{ .wc = 0x1F6B6, .width = 2 },
156 	{ .wc = 0x1F6C0, .width = 2 },
157 	{ .wc = 0x1F6CC, .width = 2 },
158 	{ .wc = 0x1F90C, .width = 2 },
159 	{ .wc = 0x1F90F, .width = 2 },
160 	{ .wc = 0x1F918, .width = 2 },
161 	{ .wc = 0x1F919, .width = 2 },
162 	{ .wc = 0x1F91A, .width = 2 },
163 	{ .wc = 0x1F91B, .width = 2 },
164 	{ .wc = 0x1F91C, .width = 2 },
165 	{ .wc = 0x1F91D, .width = 2 },
166 	{ .wc = 0x1F91E, .width = 2 },
167 	{ .wc = 0x1F91F, .width = 2 },
168 	{ .wc = 0x1F926, .width = 2 },
169 	{ .wc = 0x1F930, .width = 2 },
170 	{ .wc = 0x1F931, .width = 2 },
171 	{ .wc = 0x1F932, .width = 2 },
172 	{ .wc = 0x1F933, .width = 2 },
173 	{ .wc = 0x1F934, .width = 2 },
174 	{ .wc = 0x1F935, .width = 2 },
175 	{ .wc = 0x1F936, .width = 2 },
176 	{ .wc = 0x1F937, .width = 2 },
177 	{ .wc = 0x1F938, .width = 2 },
178 	{ .wc = 0x1F939, .width = 2 },
179 	{ .wc = 0x1F93D, .width = 2 },
180 	{ .wc = 0x1F93E, .width = 2 },
181 	{ .wc = 0x1F977, .width = 2 },
182 	{ .wc = 0x1F9B5, .width = 2 },
183 	{ .wc = 0x1F9B6, .width = 2 },
184 	{ .wc = 0x1F9B8, .width = 2 },
185 	{ .wc = 0x1F9B9, .width = 2 },
186 	{ .wc = 0x1F9BB, .width = 2 },
187 	{ .wc = 0x1F9CD, .width = 2 },
188 	{ .wc = 0x1F9CE, .width = 2 },
189 	{ .wc = 0x1F9CF, .width = 2 },
190 	{ .wc = 0x1F9D1, .width = 2 },
191 	{ .wc = 0x1F9D2, .width = 2 },
192 	{ .wc = 0x1F9D3, .width = 2 },
193 	{ .wc = 0x1F9D4, .width = 2 },
194 	{ .wc = 0x1F9D5, .width = 2 },
195 	{ .wc = 0x1F9D6, .width = 2 },
196 	{ .wc = 0x1F9D7, .width = 2 },
197 	{ .wc = 0x1F9D8, .width = 2 },
198 	{ .wc = 0x1F9D9, .width = 2 },
199 	{ .wc = 0x1F9DA, .width = 2 },
200 	{ .wc = 0x1F9DB, .width = 2 },
201 	{ .wc = 0x1F9DC, .width = 2 },
202 	{ .wc = 0x1F9DD, .width = 2 },
203 	{ .wc = 0x1FAC3, .width = 2 },
204 	{ .wc = 0x1FAC4, .width = 2 },
205 	{ .wc = 0x1FAC5, .width = 2 },
206 	{ .wc = 0x1FAF0, .width = 2 },
207 	{ .wc = 0x1FAF1, .width = 2 },
208 	{ .wc = 0x1FAF2, .width = 2 },
209 	{ .wc = 0x1FAF3, .width = 2 },
210 	{ .wc = 0x1FAF4, .width = 2 },
211 	{ .wc = 0x1FAF5, .width = 2 },
212 	{ .wc = 0x1FAF6, .width = 2 },
213 	{ .wc = 0x1FAF7, .width = 2 },
214 	{ .wc = 0x1FAF8, .width = 2 }
215 };
216 
217 struct utf8_item {
218 	RB_ENTRY(utf8_item)	index_entry;
219 	u_int			index;
220 
221 	RB_ENTRY(utf8_item)	data_entry;
222 	char			data[UTF8_SIZE];
223 	u_char			size;
224 };
225 
226 static int
227 utf8_data_cmp(struct utf8_item *ui1, struct utf8_item *ui2)
228 {
229 	if (ui1->size < ui2->size)
230 		return (-1);
231 	if (ui1->size > ui2->size)
232 		return (1);
233 	return (memcmp(ui1->data, ui2->data, ui1->size));
234 }
235 RB_HEAD(utf8_data_tree, utf8_item);
236 RB_GENERATE_STATIC(utf8_data_tree, utf8_item, data_entry, utf8_data_cmp);
237 static struct utf8_data_tree utf8_data_tree = RB_INITIALIZER(utf8_data_tree);
238 
239 static int
240 utf8_index_cmp(struct utf8_item *ui1, struct utf8_item *ui2)
241 {
242 	if (ui1->index < ui2->index)
243 		return (-1);
244 	if (ui1->index > ui2->index)
245 		return (1);
246 	return (0);
247 }
248 RB_HEAD(utf8_index_tree, utf8_item);
249 RB_GENERATE_STATIC(utf8_index_tree, utf8_item, index_entry, utf8_index_cmp);
250 static struct utf8_index_tree utf8_index_tree = RB_INITIALIZER(utf8_index_tree);
251 
252 static int	utf8_no_width;
253 static u_int	utf8_next_index;
254 
255 #define UTF8_GET_SIZE(uc) (((uc) >> 24) & 0x1f)
256 #define UTF8_GET_WIDTH(uc) (((uc) >> 29) - 1)
257 
258 #define UTF8_SET_SIZE(size) (((utf8_char)(size)) << 24)
259 #define UTF8_SET_WIDTH(width) ((((utf8_char)(width)) + 1) << 29)
260 
261 /* Get a UTF-8 item from data. */
262 static struct utf8_item *
263 utf8_item_by_data(const u_char *data, size_t size)
264 {
265 	struct utf8_item	ui;
266 
267 	memcpy(ui.data, data, size);
268 	ui.size = size;
269 
270 	return (RB_FIND(utf8_data_tree, &utf8_data_tree, &ui));
271 }
272 
273 /* Get a UTF-8 item from data. */
274 static struct utf8_item *
275 utf8_item_by_index(u_int index)
276 {
277 	struct utf8_item	ui;
278 
279 	ui.index = index;
280 
281 	return (RB_FIND(utf8_index_tree, &utf8_index_tree, &ui));
282 }
283 
284 /* Find a codepoint in the cache. */
285 static struct utf8_width_item *
286 utf8_find_in_width_cache(wchar_t wc)
287 {
288 	struct utf8_width_item	uw;
289 
290 	uw.wc = wc;
291 	return RB_FIND(utf8_width_cache, &utf8_width_cache, &uw);
292 }
293 
294 /* Parse a single codepoint option. */
295 static void
296 utf8_add_to_width_cache(const char *s)
297 {
298 	struct utf8_width_item	*uw, *old;
299 	char			*copy, *cp, *endptr;
300 	u_int			 width;
301 	const char		*errstr;
302 	struct utf8_data	*ud;
303 	wchar_t			 wc;
304 	unsigned long long	 n;
305 
306 	copy = xstrdup(s);
307 	if ((cp = strchr(copy, '=')) == NULL) {
308 		free(copy);
309 		return;
310 	}
311 	*cp++ = '\0';
312 
313 	width = strtonum(cp, 0, 2, &errstr);
314 	if (errstr != NULL) {
315 		free(copy);
316 		return;
317 	}
318 
319 	if (strncmp(copy, "U+", 2) == 0) {
320 		errno = 0;
321 		n = strtoull(copy + 2, &endptr, 16);
322 		if (copy[2] == '\0' ||
323 		    *endptr != '\0' ||
324 		    n == 0 ||
325 		    n > WCHAR_MAX ||
326 		    (errno == ERANGE && n == ULLONG_MAX)) {
327 			free(copy);
328 			return;
329 		}
330 		wc = n;
331 	} else {
332 		utf8_no_width = 1;
333 		ud = utf8_fromcstr(copy);
334 		utf8_no_width = 0;
335 		if (ud[0].size == 0 || ud[1].size != 0) {
336 			free(ud);
337 			free(copy);
338 			return;
339 		}
340 #ifdef HAVE_UTF8PROC
341 		if (utf8proc_mbtowc(&wc, ud[0].data, ud[0].size) <= 0) {
342 #else
343 		if (mbtowc(&wc, ud[0].data, ud[0].size) <= 0) {
344 #endif
345 			free(ud);
346 			free(copy);
347 			return;
348 		}
349 		free(ud);
350 	}
351 
352 	log_debug("Unicode width cache: %08X=%u", (u_int)wc, width);
353 
354 	uw = xcalloc(1, sizeof *uw);
355 	uw->wc = wc;
356 	uw->width = width;
357 	uw->allocated = 1;
358 
359 	old = RB_INSERT(utf8_width_cache, &utf8_width_cache, uw);
360 	if (old != NULL) {
361 		RB_REMOVE(utf8_width_cache, &utf8_width_cache, old);
362 		if (old->allocated)
363 			free(old);
364 		RB_INSERT(utf8_width_cache, &utf8_width_cache, uw);
365 	}
366 
367 	free(copy);
368 }
369 
370 /* Rebuild cache of widths. */
371 void
372 utf8_update_width_cache(void)
373 {
374 	struct utf8_width_item		*uw, *uw1;
375 	struct options_entry		*o;
376 	struct options_array_item	*a;
377 	u_int				 i;
378 
379 	RB_FOREACH_SAFE (uw, utf8_width_cache, &utf8_width_cache, uw1) {
380 		RB_REMOVE(utf8_width_cache, &utf8_width_cache, uw);
381 		if (uw->allocated)
382 			free(uw);
383 	}
384 
385 	for (i = 0; i < nitems(utf8_default_width_cache); i++) {
386 		RB_INSERT(utf8_width_cache, &utf8_width_cache,
387 		    &utf8_default_width_cache[i]);
388 	}
389 
390 	o = options_get(global_options, "codepoint-widths");
391 	a = options_array_first(o);
392 	while (a != NULL) {
393 		utf8_add_to_width_cache(options_array_item_value(a)->string);
394 		a = options_array_next(a);
395 	}
396 }
397 
398 /* Add a UTF-8 item. */
399 static int
400 utf8_put_item(const u_char *data, size_t size, u_int *index)
401 {
402 	struct utf8_item	*ui;
403 
404 	ui = utf8_item_by_data(data, size);
405 	if (ui != NULL) {
406 		*index = ui->index;
407 		log_debug("%s: found %.*s = %u", __func__, (int)size, data,
408 		    *index);
409 		return (0);
410 	}
411 
412 	if (utf8_next_index == 0xffffff + 1)
413 		return (-1);
414 
415 	ui = xcalloc(1, sizeof *ui);
416 	ui->index = utf8_next_index++;
417 	RB_INSERT(utf8_index_tree, &utf8_index_tree, ui);
418 
419 	memcpy(ui->data, data, size);
420 	ui->size = size;
421 	RB_INSERT(utf8_data_tree, &utf8_data_tree, ui);
422 
423 	*index = ui->index;
424 	log_debug("%s: added %.*s = %u", __func__, (int)size, data, *index);
425 	return (0);
426 }
427 
428 /* Get UTF-8 character from data. */
429 enum utf8_state
430 utf8_from_data(const struct utf8_data *ud, utf8_char *uc)
431 {
432 	u_int	index;
433 
434 	if (ud->width > 2)
435 		fatalx("invalid UTF-8 width: %u", ud->width);
436 
437 	if (ud->size > UTF8_SIZE)
438 		goto fail;
439 	if (ud->size <= 3) {
440 		index = (((utf8_char)ud->data[2] << 16)|
441 			  ((utf8_char)ud->data[1] << 8)|
442 			  ((utf8_char)ud->data[0]));
443 	} else if (utf8_put_item(ud->data, ud->size, &index) != 0)
444 		goto fail;
445 	*uc = UTF8_SET_SIZE(ud->size)|UTF8_SET_WIDTH(ud->width)|index;
446 	log_debug("%s: (%d %d %.*s) -> %08x", __func__, ud->width, ud->size,
447 	    (int)ud->size, ud->data, *uc);
448 	return (UTF8_DONE);
449 
450 fail:
451 	if (ud->width == 0)
452 		*uc = UTF8_SET_SIZE(0)|UTF8_SET_WIDTH(0);
453 	else if (ud->width == 1)
454 		*uc = UTF8_SET_SIZE(1)|UTF8_SET_WIDTH(1)|0x20;
455 	else
456 		*uc = UTF8_SET_SIZE(1)|UTF8_SET_WIDTH(1)|0x2020;
457 	return (UTF8_ERROR);
458 }
459 
460 /* Get UTF-8 data from character. */
461 void
462 utf8_to_data(utf8_char uc, struct utf8_data *ud)
463 {
464 	struct utf8_item	*ui;
465 	u_int			 index;
466 
467 	memset(ud, 0, sizeof *ud);
468 	ud->size = ud->have = UTF8_GET_SIZE(uc);
469 	ud->width = UTF8_GET_WIDTH(uc);
470 
471 	if (ud->size <= 3) {
472 		ud->data[2] = (uc >> 16);
473 		ud->data[1] = ((uc >> 8) & 0xff);
474 		ud->data[0] = (uc & 0xff);
475 	} else {
476 		index = (uc & 0xffffff);
477 		if ((ui = utf8_item_by_index(index)) == NULL)
478 			memset(ud->data, ' ', ud->size);
479 		else
480 			memcpy(ud->data, ui->data, ud->size);
481 	}
482 
483 	log_debug("%s: %08x -> (%d %d %.*s)", __func__, uc, ud->width, ud->size,
484 	    (int)ud->size, ud->data);
485 }
486 
487 /* Get UTF-8 character from a single ASCII character. */
488 u_int
489 utf8_build_one(u_char ch)
490 {
491 	return (UTF8_SET_SIZE(1)|UTF8_SET_WIDTH(1)|ch);
492 }
493 
494 /* Set a single character. */
495 void
496 utf8_set(struct utf8_data *ud, u_char ch)
497 {
498 	static const struct utf8_data empty = { { 0 }, 1, 1, 1 };
499 
500 	memcpy(ud, &empty, sizeof *ud);
501 	*ud->data = ch;
502 }
503 
504 /* Copy UTF-8 character. */
505 void
506 utf8_copy(struct utf8_data *to, const struct utf8_data *from)
507 {
508 	u_int	i;
509 
510 	memcpy(to, from, sizeof *to);
511 
512 	for (i = to->size; i < sizeof to->data; i++)
513 		to->data[i] = '\0';
514 }
515 
516 /* Get width of Unicode character. */
517 static enum utf8_state
518 utf8_width(struct utf8_data *ud, int *width)
519 {
520 	struct utf8_width_item	*uw;
521 	wchar_t			 wc;
522 
523 	if (utf8_towc(ud, &wc) != UTF8_DONE)
524 		return (UTF8_ERROR);
525 	uw = utf8_find_in_width_cache(wc);
526 	if (uw != NULL) {
527 		*width = uw->width;
528 		log_debug("cached width for %08X is %d", (u_int)wc, *width);
529 		return (UTF8_DONE);
530 	}
531 
532 	*width = wcwidth(wc);
533 	log_debug("wcwidth(%05X) returned %d", (u_int)wc, *width);
534 	if (*width < 0) {
535 		/*
536 		 * C1 control characters are nonprintable, so they are always
537 		 * zero width.
538 		 */
539 		*width = (wc >= 0x80 && wc <= 0x9f) ? 0 : 1;
540 	}
541 	if (*width >= 0 && *width <= 0xff)
542 		return (UTF8_DONE);
543 	return (UTF8_ERROR);
544 }
545 
546 /* Convert UTF-8 character to wide character. */
547 enum utf8_state
548 utf8_towc(const struct utf8_data *ud, wchar_t *wc)
549 {
550 	switch (mbtowc(wc, ud->data, ud->size)) {
551 	case -1:
552 		log_debug("UTF-8 %.*s, mbtowc() %d", (int)ud->size, ud->data,
553 		    errno);
554 		mbtowc(NULL, NULL, MB_CUR_MAX);
555 		return (UTF8_ERROR);
556 	case 0:
557 		return (UTF8_ERROR);
558 	}
559 	log_debug("UTF-8 %.*s is %05X", (int)ud->size, ud->data, (u_int)*wc);
560 	return (UTF8_DONE);
561 }
562 
563 /* Convert wide character to UTF-8 character. */
564 enum utf8_state
565 utf8_fromwc(wchar_t wc, struct utf8_data *ud)
566 {
567 	int	size, width;
568 
569 	size = wctomb(ud->data, wc);
570 	if (size < 0) {
571 		log_debug("UTF-8 %d, wctomb() %d", wc, errno);
572 		wctomb(NULL, 0);
573 		return (UTF8_ERROR);
574 	}
575 	if (size == 0)
576 		return (UTF8_ERROR);
577 	ud->size = ud->have = size;
578 	if (utf8_width(ud, &width) == UTF8_DONE) {
579 		ud->width = width;
580 		return (UTF8_DONE);
581 	}
582 	return (UTF8_ERROR);
583 }
584 
585 /*
586  * Open UTF-8 sequence.
587  *
588  * 11000010-11011111 C2-DF start of 2-byte sequence
589  * 11100000-11101111 E0-EF start of 3-byte sequence
590  * 11110000-11110100 F0-F4 start of 4-byte sequence
591  */
592 enum utf8_state
593 utf8_open(struct utf8_data *ud, u_char ch)
594 {
595 	memset(ud, 0, sizeof *ud);
596 	if (ch >= 0xc2 && ch <= 0xdf)
597 		ud->size = 2;
598 	else if (ch >= 0xe0 && ch <= 0xef)
599 		ud->size = 3;
600 	else if (ch >= 0xf0 && ch <= 0xf4)
601 		ud->size = 4;
602 	else
603 		return (UTF8_ERROR);
604 	utf8_append(ud, ch);
605 	return (UTF8_MORE);
606 }
607 
608 /* Append character to UTF-8, closing if finished. */
609 enum utf8_state
610 utf8_append(struct utf8_data *ud, u_char ch)
611 {
612 	int	width;
613 
614 	if (ud->have >= ud->size)
615 		fatalx("UTF-8 character overflow");
616 	if (ud->size > sizeof ud->data)
617 		fatalx("UTF-8 character size too large");
618 
619 	if (ud->have != 0 && (ch & 0xc0) != 0x80)
620 		ud->width = 0xff;
621 
622 	ud->data[ud->have++] = ch;
623 	if (ud->have != ud->size)
624 		return (UTF8_MORE);
625 
626 	if (!utf8_no_width) {
627 		if (ud->width == 0xff)
628 			return (UTF8_ERROR);
629 		if (utf8_width(ud, &width) != UTF8_DONE)
630 			return (UTF8_ERROR);
631 		ud->width = width;
632 	}
633 
634 	return (UTF8_DONE);
635 }
636 
637 /*
638  * Encode len characters from src into dst, which is guaranteed to have four
639  * bytes available for each character from src (for \abc or UTF-8) plus space
640  * for \0.
641  */
642 int
643 utf8_strvis(char *dst, const char *src, size_t len, int flag)
644 {
645 	struct utf8_data	 ud;
646 	const char		*start = dst, *end = src + len;
647 	enum utf8_state		 more;
648 	size_t			 i;
649 
650 	while (src < end) {
651 		if ((more = utf8_open(&ud, *src)) == UTF8_MORE) {
652 			while (++src < end && more == UTF8_MORE)
653 				more = utf8_append(&ud, *src);
654 			if (more == UTF8_DONE) {
655 				/* UTF-8 character finished. */
656 				for (i = 0; i < ud.size; i++)
657 					*dst++ = ud.data[i];
658 				continue;
659 			}
660 			/* Not a complete, valid UTF-8 character. */
661 			src -= ud.have;
662 		}
663 		if ((flag & VIS_DQ) && src[0] == '$' && src < end - 1) {
664 			if (isalpha((u_char)src[1]) ||
665 			    src[1] == '_' ||
666 			    src[1] == '{')
667 				*dst++ = '\\';
668 			*dst++ = '$';
669 		} else if (src < end - 1)
670 			dst = vis(dst, src[0], flag, src[1]);
671 		else if (src < end)
672 			dst = vis(dst, src[0], flag, '\0');
673 		src++;
674 	}
675 	*dst = '\0';
676 	return (dst - start);
677 }
678 
679 /* Same as utf8_strvis but allocate the buffer. */
680 int
681 utf8_stravis(char **dst, const char *src, int flag)
682 {
683 	char	*buf;
684 	int	 len;
685 
686 	buf = xreallocarray(NULL, 4, strlen(src) + 1);
687 	len = utf8_strvis(buf, src, strlen(src), flag);
688 
689 	*dst = xrealloc(buf, len + 1);
690 	return (len);
691 }
692 
693 /* Same as utf8_strvis but allocate the buffer. */
694 int
695 utf8_stravisx(char **dst, const char *src, size_t srclen, int flag)
696 {
697 	char	*buf;
698 	int	 len;
699 
700 	buf = xreallocarray(NULL, 4, srclen + 1);
701 	len = utf8_strvis(buf, src, srclen, flag);
702 
703 	*dst = xrealloc(buf, len + 1);
704 	return (len);
705 }
706 
707 /* Does this string contain anything that isn't valid UTF-8? */
708 int
709 utf8_isvalid(const char *s)
710 {
711 	struct utf8_data ud;
712 	const char	*end;
713 	enum utf8_state	 more;
714 
715 	end = s + strlen(s);
716 	while (s < end) {
717 		if ((more = utf8_open(&ud, *s)) == UTF8_MORE) {
718 			while (++s < end && more == UTF8_MORE)
719 				more = utf8_append(&ud, *s);
720 			if (more == UTF8_DONE)
721 				continue;
722 			return (0);
723 		}
724 		if (*s < 0x20 || *s > 0x7e)
725 			return (0);
726 		s++;
727 	}
728 	return (1);
729 }
730 
731 /*
732  * Sanitize a string, changing any UTF-8 characters to '_'. Caller should free
733  * the returned string. Anything not valid printable ASCII or UTF-8 is
734  * stripped.
735  */
736 char *
737 utf8_sanitize(const char *src)
738 {
739 	char		*dst = NULL;
740 	size_t		 n = 0;
741 	enum utf8_state	 more;
742 	struct utf8_data ud;
743 	u_int		 i;
744 
745 	while (*src != '\0') {
746 		dst = xreallocarray(dst, n + 1, sizeof *dst);
747 		if ((more = utf8_open(&ud, *src)) == UTF8_MORE) {
748 			while (*++src != '\0' && more == UTF8_MORE)
749 				more = utf8_append(&ud, *src);
750 			if (more == UTF8_DONE) {
751 				dst = xreallocarray(dst, n + ud.width,
752 				    sizeof *dst);
753 				for (i = 0; i < ud.width; i++)
754 					dst[n++] = '_';
755 				continue;
756 			}
757 			src -= ud.have;
758 		}
759 		if (*src > 0x1f && *src < 0x7f)
760 			dst[n++] = *src;
761 		else
762 			dst[n++] = '_';
763 		src++;
764 	}
765 	dst = xreallocarray(dst, n + 1, sizeof *dst);
766 	dst[n] = '\0';
767 	return (dst);
768 }
769 
770 /* Get UTF-8 buffer length. */
771 size_t
772 utf8_strlen(const struct utf8_data *s)
773 {
774 	size_t	i;
775 
776 	for (i = 0; s[i].size != 0; i++)
777 		/* nothing */;
778 	return (i);
779 }
780 
781 /* Get UTF-8 string width. */
782 u_int
783 utf8_strwidth(const struct utf8_data *s, ssize_t n)
784 {
785 	ssize_t	i;
786 	u_int	width = 0;
787 
788 	for (i = 0; s[i].size != 0; i++) {
789 		if (n != -1 && n == i)
790 			break;
791 		width += s[i].width;
792 	}
793 	return (width);
794 }
795 
796 /*
797  * Convert a string into a buffer of UTF-8 characters. Terminated by size == 0.
798  * Caller frees.
799  */
800 struct utf8_data *
801 utf8_fromcstr(const char *src)
802 {
803 	struct utf8_data	*dst = NULL;
804 	size_t			 n = 0;
805 	enum utf8_state		 more;
806 
807 	while (*src != '\0') {
808 		dst = xreallocarray(dst, n + 1, sizeof *dst);
809 		if ((more = utf8_open(&dst[n], *src)) == UTF8_MORE) {
810 			while (*++src != '\0' && more == UTF8_MORE)
811 				more = utf8_append(&dst[n], *src);
812 			if (more == UTF8_DONE) {
813 				n++;
814 				continue;
815 			}
816 			src -= dst[n].have;
817 		}
818 		utf8_set(&dst[n], *src);
819 		n++;
820 		src++;
821 	}
822 	dst = xreallocarray(dst, n + 1, sizeof *dst);
823 	dst[n].size = 0;
824 	return (dst);
825 }
826 
827 /* Convert from a buffer of UTF-8 characters into a string. Caller frees. */
828 char *
829 utf8_tocstr(struct utf8_data *src)
830 {
831 	char	*dst = NULL;
832 	size_t	 n = 0;
833 
834 	for(; src->size != 0; src++) {
835 		dst = xreallocarray(dst, n + src->size, 1);
836 		memcpy(dst + n, src->data, src->size);
837 		n += src->size;
838 	}
839 	dst = xreallocarray(dst, n + 1, 1);
840 	dst[n] = '\0';
841 	return (dst);
842 }
843 
844 /* Get width of UTF-8 string. */
845 u_int
846 utf8_cstrwidth(const char *s)
847 {
848 	struct utf8_data	tmp;
849 	u_int			width;
850 	enum utf8_state		more;
851 
852 	width = 0;
853 	while (*s != '\0') {
854 		if ((more = utf8_open(&tmp, *s)) == UTF8_MORE) {
855 			while (*++s != '\0' && more == UTF8_MORE)
856 				more = utf8_append(&tmp, *s);
857 			if (more == UTF8_DONE) {
858 				width += tmp.width;
859 				continue;
860 			}
861 			s -= tmp.have;
862 		}
863 		if (*s > 0x1f && *s != 0x7f)
864 			width++;
865 		s++;
866 	}
867 	return (width);
868 }
869 
870 /* Pad UTF-8 string to width on the left. Caller frees. */
871 char *
872 utf8_padcstr(const char *s, u_int width)
873 {
874 	size_t	 slen;
875 	char	*out;
876 	u_int	 n, i;
877 
878 	n = utf8_cstrwidth(s);
879 	if (n >= width)
880 		return (xstrdup(s));
881 
882 	slen = strlen(s);
883 	out = xmalloc(slen + 1 + (width - n));
884 	memcpy(out, s, slen);
885 	for (i = n; i < width; i++)
886 		out[slen++] = ' ';
887 	out[slen] = '\0';
888 	return (out);
889 }
890 
891 /* Pad UTF-8 string to width on the right. Caller frees. */
892 char *
893 utf8_rpadcstr(const char *s, u_int width)
894 {
895 	size_t	 slen;
896 	char	*out;
897 	u_int	 n, i;
898 
899 	n = utf8_cstrwidth(s);
900 	if (n >= width)
901 		return (xstrdup(s));
902 
903 	slen = strlen(s);
904 	out = xmalloc(slen + 1 + (width - n));
905 	for (i = 0; i < width - n; i++)
906 		out[i] = ' ';
907 	memcpy(out + i, s, slen);
908 	out[i + slen] = '\0';
909 	return (out);
910 }
911 
912 int
913 utf8_cstrhas(const char *s, const struct utf8_data *ud)
914 {
915 	struct utf8_data	*copy, *loop;
916 	int			 found = 0;
917 
918 	copy = utf8_fromcstr(s);
919 	for (loop = copy; loop->size != 0; loop++) {
920 		if (loop->size != ud->size)
921 			continue;
922 		if (memcmp(loop->data, ud->data, loop->size) == 0) {
923 			found = 1;
924 			break;
925 		}
926 	}
927 	free(copy);
928 
929 	return (found);
930 }
931