xref: /dragonfly/usr.bin/localedef/wide.c (revision 279dd846)
1 /*
2  * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
3  * Copyright 2012 Garrett D'Amore <garrett@damore.org>  All rights reserved.
4  * Copyright 2015 John Marino <draco@marino.st>
5  *
6  * This source code is derived from the illumos localedef command, and
7  * provided under BSD-style license terms by Nexenta Systems, Inc.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  *
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
20  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
23  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 /*
33  * The functions in this file convert from the standard multibyte forms
34  * to the wide character forms used internally by libc.  Unfortunately,
35  * this approach means that we need a method for each and every encoding.
36  */
37 
38 #include <stdlib.h>
39 #include <wchar.h>
40 #include <string.h>
41 #include <sys/types.h>
42 #include "localedef.h"
43 
44 static int towide_none(wchar_t *, const char *, unsigned);
45 static int towide_utf8(wchar_t *, const char *, unsigned);
46 static int towide_big5(wchar_t *, const char *, unsigned);
47 static int towide_gbk(wchar_t *, const char *, unsigned);
48 static int towide_gb2312(wchar_t *, const char *, unsigned);
49 static int towide_gb18030(wchar_t *, const char *, unsigned);
50 static int towide_mskanji(wchar_t *, const char *, unsigned);
51 static int towide_euccn(wchar_t *, const char *, unsigned);
52 static int towide_eucjp(wchar_t *, const char *, unsigned);
53 static int towide_euckr(wchar_t *, const char *, unsigned);
54 static int towide_euctw(wchar_t *, const char *, unsigned);
55 
56 static int tomb_none(char *, wchar_t);
57 static int tomb_utf8(char *, wchar_t);
58 static int tomb_mbs(char *, wchar_t);
59 
60 static int (*_towide)(wchar_t *, const char *, unsigned) = towide_none;
61 static int (*_tomb)(char *, wchar_t) = tomb_none;
62 static const char *_encoding = "NONE";
63 static int _nbits = 7;
64 
65 /*
66  * Table of supported encodings.  We only bother to list the multibyte
67  * encodings here, because single byte locales are handed by "NONE".
68  */
69 static struct {
70 	const char *name;
71 	/* the name that the underlying libc implemenation uses */
72 	const char *cname;
73 	/* the maximum number of bits required for priorities */
74 	int nbits;
75 	int (*towide)(wchar_t *, const char *, unsigned);
76 	int (*tomb)(char *, wchar_t);
77 } mb_encodings[] = {
78 	/*
79 	 * UTF8 values max out at 0x1fffff (although in theory there could
80 	 * be later extensions, but it won't happen.)  This means we only need
81 	 * 21 bits to be able to encode the entire range of priorities.
82 	 */
83 	{ "UTF-8",	"UTF-8",	21, towide_utf8, tomb_utf8 },
84 	{ "UTF8",	"UTF-8",	21, towide_utf8, tomb_utf8 },
85 	{ "utf8",	"UTF-8",	21, towide_utf8, tomb_utf8 },
86 	{ "utf-8",	"UTF-8",	21, towide_utf8, tomb_utf8 },
87 
88 	{ "EUC-CN",	"EUC-CN",	16, towide_euccn, tomb_mbs },
89 	{ "eucCN",	"EUC-CN",	16, towide_euccn, tomb_mbs },
90 	/*
91 	 * Becuase the 3-byte form of EUC-JP use the same leading byte,
92 	 * only 17 bits required to provide unique priorities.  (The low
93 	 * bit of that first byte is set.)  By setting this value low,
94 	 * we can get by with only 3 bytes in the strxfrm expansion.
95 	 */
96 	{ "EUC-JP",	"EUC-JP",	17, towide_eucjp, tomb_mbs },
97 	{ "eucJP",	"EUC-JP",	17, towide_eucjp, tomb_mbs },
98 
99 	{ "EUC-KR",	"EUC-KR",	16, towide_euckr, tomb_mbs },
100 	{ "eucKR",	"EUC-KR",	16, towide_euckr, tomb_mbs },
101 	/*
102 	 * EUC-TW uses 2 bytes most of the time, but 4 bytes if the
103 	 * high order byte is 0x8E.  However, with 4 byte encodings,
104 	 * the third byte will be A0-B0.  So we only need to consider
105 	 * the lower order 24 bits for collation.
106 	 */
107 	{ "EUC-TW",	"EUC-TW",	24, towide_euctw, tomb_mbs },
108 	{ "eucTW",	"EUC-TW",	24, towide_euctw, tomb_mbs },
109 
110 	{ "MS_Kanji",	"MSKanji",	16, towide_mskanji, tomb_mbs },
111 	{ "MSKanji",	"MSKanji",	16, towide_mskanji, tomb_mbs },
112 	{ "PCK",	"MSKanji",	16, towide_mskanji, tomb_mbs },
113 	{ "SJIS",	"MSKanji",	16, towide_mskanji, tomb_mbs },
114 	{ "Shift_JIS",	"MSKanji",	16, towide_mskanji, tomb_mbs },
115 
116 	{ "BIG5",	"BIG5",		16, towide_big5, tomb_mbs },
117 	{ "big5",	"BIG5",		16, towide_big5, tomb_mbs },
118 	{ "Big5",	"BIG5",		16, towide_big5, tomb_mbs },
119 
120 	{ "GBK",	"GBK",		16, towide_gbk,	tomb_mbs },
121 
122 	/*
123 	 * GB18030 can get away with just 31 bits.  This is because the
124 	 * high order bit is always set for 4 byte values, and the
125 	 * at least one of the other bits in that 4 byte value will
126 	 * be non-zero.
127 	 */
128 	{ "GB18030",	"GB18030",	31, towide_gb18030, tomb_mbs },
129 
130 	/*
131 	 * This should probably be an aliase for euc-cn, or vice versa.
132 	 */
133 	{ "GB2312",	"GB2312",	16, towide_gb2312, tomb_mbs },
134 
135 	{ NULL, NULL, 0, 0, 0 },
136 };
137 
138 static char *
139 show_mb(const char *mb)
140 {
141 	static char buf[64];
142 
143 	/* ASCII stuff we just print */
144 	if (isascii(*mb) && isgraph(*mb)) {
145 		buf[0] = *mb;
146 		buf[1] = 0;
147 		return (buf);
148 	}
149 	buf[0] = 0;
150 	while (*mb != 0) {
151 		char scr[8];
152 		(void) snprintf(scr, sizeof (scr), "\\x%02x", *mb);
153 		(void) strlcat(buf, scr, sizeof (buf));
154 		mb++;
155 	}
156 	return (buf);
157 }
158 
159 static char	*widemsg;
160 
161 void
162 werr(const char *fmt, ...)
163 {
164 	char	*msg;
165 
166 	va_list	va;
167 	va_start(va, fmt);
168 	(void) vasprintf(&msg, fmt, va);
169 	va_end(va);
170 
171 	free(widemsg);
172 	widemsg = msg;
173 }
174 
175 /*
176  * This is used for 8-bit encodings.
177  */
178 int
179 towide_none(wchar_t *c, const char *mb, unsigned n __unused)
180 {
181 	if (mb_cur_max != 1) {
182 		werr("invalid or unsupported multibyte locale");
183 		return (-1);
184 	}
185 	*c = (uint8_t)*mb;
186 	return (1);
187 }
188 
189 int
190 tomb_none(char *mb, wchar_t wc)
191 {
192 	if (mb_cur_max != 1) {
193 		werr("invalid or unsupported multibyte locale");
194 		return (-1);
195 	}
196 	*(uint8_t *)mb = (wc & 0xff);
197 	mb[1] = 0;
198 	return (1);
199 }
200 
201 /*
202  * UTF-8 stores wide characters in UTF-32 form.
203  */
204 int
205 towide_utf8(wchar_t *wc, const char *mb, unsigned n)
206 {
207 	wchar_t	c;
208 	int	nb;
209 	int	lv;	/* lowest legal value */
210 	int	i;
211 	const uint8_t *s = (const uint8_t *)mb;
212 
213 	c = *s;
214 
215 	if ((c & 0x80) == 0) {
216 		/* 7-bit ASCII */
217 		*wc = c;
218 		return (1);
219 	} else if ((c & 0xe0) == 0xc0) {
220 		/* u80-u7ff - two bytes encoded */
221 		nb = 2;
222 		lv = 0x80;
223 		c &= ~0xe0;
224 	} else if ((c & 0xf0) == 0xe0) {
225 		/* u800-uffff - three bytes encoded */
226 		nb = 3;
227 		lv = 0x800;
228 		c &= ~0xf0;
229 	} else if ((c & 0xf8) == 0xf0) {
230 		/* u1000-u1fffff - four bytes encoded */
231 		nb = 4;
232 		lv = 0x1000;
233 		c &= ~0xf8;
234 	} else {
235 		/* 5 and 6 byte encodings are not legal unicode */
236 		werr("utf8 encoding too large (%s)", show_mb(mb));
237 		return (-1);
238 	}
239 	if (nb > (int)n) {
240 		werr("incomplete utf8 sequence (%s)", show_mb(mb));
241 		return (-1);
242 	}
243 
244 	for (i = 1; i < nb; i++) {
245 		if (((s[i]) & 0xc0) != 0x80) {
246 			werr("illegal utf8 byte (%x)", s[i]);
247 			return (-1);
248 		}
249 		c <<= 6;
250 		c |= (s[i] & 0x3f);
251 	}
252 
253 	if (c < lv) {
254 		werr("illegal redundant utf8 encoding (%s)", show_mb(mb));
255 		return (-1);
256 	}
257 	*wc = c;
258 	return (nb);
259 }
260 
261 int
262 tomb_utf8(char *mb, wchar_t wc)
263 {
264 	uint8_t *s = (uint8_t *)mb;
265 	uint8_t msk;
266 	int cnt;
267 	int i;
268 
269 	if (wc <= 0x7f) {
270 		s[0] = wc & 0x7f;
271 		s[1] = 0;
272 		return (1);
273 	}
274 	if (wc <= 0x7ff) {
275 		cnt = 2;
276 		msk = 0xc0;
277 	} else if (wc <= 0xffff) {
278 		cnt = 3;
279 		msk = 0xe0;
280 	} else if (wc <= 0x1fffff) {
281 		cnt = 4;
282 		msk = 0xf0;
283 	} else {
284 		werr("illegal uf8 char (%x)", wc);
285 		return (-1);
286 	}
287 	for (i = cnt - 1; i; i--) {
288 		s[i] = (wc & 0x3f) | 0x80;
289 		wc >>= 6;
290 	}
291 	s[0] = (msk) | wc;
292 	s[cnt] = 0;
293 	return (cnt);
294 }
295 
296 /*
297  * Several encodings share a simplistic dual byte encoding.  In these
298  * forms, they all indicate that a two byte sequence is to be used if
299  * the first byte has its high bit set.  They all store this simple
300  * encoding as a 16-bit value, although a great many of the possible
301  * code points are not used in most character sets.  This gives a possible
302  * set of just over 32,000 valid code points.
303  *
304  * 0x00 - 0x7f		- 1 byte encoding
305  * 0x80 - 0x7fff	- illegal
306  * 0x8000 - 0xffff	- 2 byte encoding
307  */
308 
309 #pragma GCC diagnostic push
310 #pragma GCC diagnostic ignored "-Wcast-qual"
311 
312 static int
313 towide_dbcs(wchar_t *wc, const char *mb, unsigned n)
314 {
315 	wchar_t	c;
316 
317 	c = *(uint8_t *)mb;
318 
319 	if ((c & 0x80) == 0) {
320 		/* 7-bit */
321 		*wc = c;
322 		return (1);
323 	}
324 	if (n < 2) {
325 		werr("incomplete character sequence (%s)", show_mb(mb));
326 		return (-1);
327 	}
328 
329 	/* Store both bytes as a single 16-bit wide. */
330 	c <<= 8;
331 	c |= (uint8_t)(mb[1]);
332 	*wc = c;
333 	return (2);
334 }
335 
336 /*
337  * Most multibyte locales just convert the wide character to the multibyte
338  * form by stripping leading null bytes, and writing the 32-bit quantity
339  * in big-endian order.
340  */
341 int
342 tomb_mbs(char *mb, wchar_t wc)
343 {
344 	uint8_t *s = (uint8_t *)mb;
345 	int 	n = 0, c;
346 
347 	if ((wc & 0xff000000U) != 0) {
348 		n = 4;
349 	} else if ((wc & 0x00ff0000U) != 0) {
350 		n = 3;
351 	} else if ((wc & 0x0000ff00U) != 0) {
352 		n = 2;
353 	} else {
354 		n = 1;
355 	}
356 	c = n;
357 	while (n) {
358 		n--;
359 		s[n] = wc & 0xff;
360 		wc >>= 8;
361 	}
362 	/* ensure null termination */
363 	s[c] = 0;
364 	return (c);
365 }
366 
367 
368 /*
369  * big5 is a simple dual byte character set.
370  */
371 int
372 towide_big5(wchar_t *wc, const char *mb, unsigned n)
373 {
374 	return (towide_dbcs(wc, mb, n));
375 }
376 
377 /*
378  * GBK encodes wides in the same way that big5 does, the high order
379  * bit of the first byte indicates a double byte character.
380  */
381 int
382 towide_gbk(wchar_t *wc, const char *mb, unsigned n)
383 {
384 	return (towide_dbcs(wc, mb, n));
385 }
386 
387 /*
388  * GB2312 is another DBCS.  Its cleaner than others in that the second
389  * byte does not encode ASCII, but it supports characters.
390  */
391 int
392 towide_gb2312(wchar_t *wc, const char *mb, unsigned n)
393 {
394 	return (towide_dbcs(wc, mb, n));
395 }
396 
397 /*
398  * GB18030.  This encodes as 8, 16, or 32-bits.
399  * 7-bit values are in 1 byte,  4 byte sequences are used when
400  * the second byte encodes 0x30-39 and all other sequences are 2 bytes.
401  */
402 int
403 towide_gb18030(wchar_t *wc, const char *mb, unsigned n)
404 {
405 	wchar_t	c;
406 
407 	c = *(uint8_t *)mb;
408 
409 	if ((c & 0x80) == 0) {
410 		/* 7-bit */
411 		*wc = c;
412 		return (1);
413 	}
414 	if (n < 2) {
415 		werr("incomplete character sequence (%s)", show_mb(mb));
416 		return (-1);
417 	}
418 
419 	/* pull in the second byte */
420 	c <<= 8;
421 	c |= (uint8_t)(mb[1]);
422 
423 	if (((c & 0xff) >= 0x30) && ((c & 0xff) <= 0x39)) {
424 		if (n < 4) {
425 			werr("incomplete 4-byte character sequence (%s)",
426 			    show_mb(mb));
427 			return (-1);
428 		}
429 		c <<= 8;
430 		c |= (uint8_t)(mb[2]);
431 		c <<= 8;
432 		c |= (uint8_t)(mb[3]);
433 		*wc = c;
434 		return (4);
435 	}
436 
437 	*wc = c;
438 	return (2);
439 }
440 
441 /*
442  * MS-Kanji (aka SJIS) is almost a clean DBCS like the others, but it
443  * also has a range of single byte characters above 0x80.  (0xa1-0xdf).
444  */
445 int
446 towide_mskanji(wchar_t *wc, const char *mb, unsigned n)
447 {
448 	wchar_t	c;
449 
450 	c = *(uint8_t *)mb;
451 
452 	if ((c < 0x80) || ((c > 0xa0) && (c < 0xe0))) {
453 		/* 7-bit */
454 		*wc = c;
455 		return (1);
456 	}
457 
458 	if (n < 2) {
459 		werr("incomplete character sequence (%s)", show_mb(mb));
460 		return (-1);
461 	}
462 
463 	/* Store both bytes as a single 16-bit wide. */
464 	c <<= 8;
465 	c |= (uint8_t)(mb[1]);
466 	*wc = c;
467 	return (2);
468 }
469 
470 /*
471  * EUC forms.  EUC encodings are "variable".  FreeBSD carries some additional
472  * variable data to encode these, but we're going to treat each as independent
473  * instead.  Its the only way we can sensibly move forward.
474  *
475  * Note that the way in which the different EUC forms vary is how wide
476  * CS2 and CS3 are and what the first byte of them is.
477  */
478 static int
479 towide_euc_impl(wchar_t *wc, const char *mb, unsigned n,
480     uint8_t cs2, uint8_t cs2width, uint8_t cs3, uint8_t cs3width)
481 {
482 	int i;
483 	int width = 2;
484 	wchar_t	c;
485 
486 	c = *(uint8_t *)mb;
487 
488 	/*
489 	 * All variations of EUC encode 7-bit ASCII as one byte, and use
490 	 * additional bytes for more than that.
491 	 */
492 	if ((c & 0x80) == 0) {
493 		/* 7-bit */
494 		*wc = c;
495 		return (1);
496 	}
497 
498 	/*
499 	 * All EUC variants reserve 0xa1-0xff to identify CS1, which
500 	 * is always two bytes wide.  Note that unused CS will be zero,
501 	 * and that cannot be true because we know that the high order
502 	 * bit must be set.
503 	 */
504 	if (c >= 0xa1) {
505 		width = 2;
506 	} else if (c == cs2) {
507 		width = cs2width;
508 	} else if (c == cs3) {
509 		width = cs3width;
510 	}
511 
512 	if ((int)n < width) {
513 		werr("incomplete character sequence (%s)", show_mb(mb));
514 		return (-1);
515 	}
516 
517 	for (i = 1; i < width; i++) {
518 		/* pull in the next byte */
519 		c <<= 8;
520 		c |= (uint8_t)(mb[i]);
521 	}
522 
523 	*wc = c;
524 	return (width);
525 }
526 
527 #pragma GCC diagnostic pop
528 
529 /*
530  * EUC-CN encodes as follows:
531  *
532  * Code set 0 (ASCII):				0x21-0x7E
533  * Code set 1 (CNS 11643-1992 Plane 1):		0xA1A1-0xFEFE
534  * Code set 2:					unused
535  * Code set 3:					unused
536  */
537 int
538 towide_euccn(wchar_t *wc, const char *mb, unsigned n)
539 {
540 	return (towide_euc_impl(wc, mb, n, 0x8e, 4, 0, 0));
541 }
542 
543 /*
544  * EUC-JP encodes as follows:
545  *
546  * Code set 0 (ASCII or JIS X 0201-1976 Roman):	0x21-0x7E
547  * Code set 1 (JIS X 0208):			0xA1A1-0xFEFE
548  * Code set 2 (half-width katakana):		0x8EA1-0x8EDF
549  * Code set 3 (JIS X 0212-1990):		0x8FA1A1-0x8FFEFE
550  */
551 int
552 towide_eucjp(wchar_t *wc, const char *mb, unsigned n)
553 {
554 	return (towide_euc_impl(wc, mb, n, 0x8e, 2, 0x8f, 3));
555 }
556 
557 /*
558  * EUC-KR encodes as follows:
559  *
560  * Code set 0 (ASCII or KS C 5636-1993):	0x21-0x7E
561  * Code set 1 (KS C 5601-1992):			0xA1A1-0xFEFE
562  * Code set 2:					unused
563  * Code set 3:					unused
564  */
565 int
566 towide_euckr(wchar_t *wc, const char *mb, unsigned n)
567 {
568 	return (towide_euc_impl(wc, mb, n, 0, 0, 0, 0));
569 }
570 
571 /*
572  * EUC-TW encodes as follows:
573  *
574  * Code set 0 (ASCII):				0x21-0x7E
575  * Code set 1 (CNS 11643-1992 Plane 1):		0xA1A1-0xFEFE
576  * Code set 2 (CNS 11643-1992 Planes 1-16):	0x8EA1A1A1-0x8EB0FEFE
577  * Code set 3:					unused
578  */
579 int
580 towide_euctw(wchar_t *wc, const char *mb, unsigned n)
581 {
582 	return (towide_euc_impl(wc, mb, n, 0x8e, 4, 0, 0));
583 }
584 
585 /*
586  * Public entry points.
587  */
588 
589 int
590 to_wide(wchar_t *wc, const char *mb)
591 {
592 	/* this won't fail hard */
593 	return (_towide(wc, mb, strlen(mb)));
594 }
595 
596 int
597 to_mb(char *mb, wchar_t wc)
598 {
599 	int	rv;
600 
601 	if ((rv = _tomb(mb, wc)) < 0) {
602 		errf(widemsg);
603 		free(widemsg);
604 		widemsg = NULL;
605 	}
606 	return (rv);
607 }
608 
609 char *
610 to_mb_string(const wchar_t *wcs)
611 {
612 	char	*mbs;
613 	char	*ptr;
614 	int	len;
615 
616 	mbs = malloc((wcslen(wcs) * mb_cur_max) + 1);
617 	if (mbs == NULL) {
618 		errf("out of memory");
619 		return (NULL);
620 	}
621 	ptr = mbs;
622 	while (*wcs) {
623 		if ((len = to_mb(ptr, *wcs)) < 0) {
624 			INTERR;
625 			free(mbs);
626 			return (NULL);
627 		}
628 		wcs++;
629 		ptr += len;
630 	}
631 	*ptr = 0;
632 	return (mbs);
633 }
634 
635 void
636 set_wide_encoding(const char *encoding)
637 {
638 	int i;
639 
640 	_towide = towide_none;
641 	_tomb = tomb_none;
642 	_encoding = "NONE";
643 	_nbits = 8;
644 
645 	for (i = 0; mb_encodings[i].name; i++) {
646 		if (strcasecmp(encoding, mb_encodings[i].name) == 0) {
647 			_towide = mb_encodings[i].towide;
648 			_tomb = mb_encodings[i].tomb;
649 			_encoding = mb_encodings[i].cname;
650 			_nbits = mb_encodings[i].nbits;
651 			break;
652 		}
653 	}
654 }
655 
656 const char *
657 get_wide_encoding(void)
658 {
659 	return (_encoding);
660 }
661 
662 int
663 max_wide(void)
664 {
665 	return ((int)((1U << _nbits) - 1));
666 }
667