xref: /freebsd/lib/libc/locale/collate.c (revision 105fd928b0b5b35ab529e5f6914788dc49582901)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright 2014 Garrett D'Amore <garrett@damore.org>
5  * Copyright 2010 Nexenta Systems, Inc.  All rights reserved.
6  * Copyright (c) 1995 Alex Tatmanjants <alex@elvisti.kiev.ua>
7  *		at Electronni Visti IA, Kiev, Ukraine.
8  *			All rights reserved.
9  *
10  * Copyright (c) 2011 The FreeBSD Foundation
11  * All rights reserved.
12  * Portions of this software were developed by David Chisnall
13  * under sponsorship from the FreeBSD Foundation.
14  *
15  * Redistribution and use in source and binary forms, with or without
16  * modification, are permitted provided that the following conditions
17  * are met:
18  * 1. Redistributions of source code must retain the above copyright
19  *    notice, this list of conditions and the following disclaimer.
20  * 2. Redistributions in binary form must reproduce the above copyright
21  *    notice, this list of conditions and the following disclaimer in the
22  *    documentation and/or other materials provided with the distribution.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  *
36  * Adapted to xlocale by John Marino <draco@marino.st>
37  */
38 
39 #include <sys/cdefs.h>
40 __FBSDID("$FreeBSD$");
41 
42 #include "namespace.h"
43 
44 #include <sys/types.h>
45 #include <sys/stat.h>
46 #include <sys/mman.h>
47 
48 #include <assert.h>
49 #include <stdio.h>
50 #include <stdlib.h>
51 #include <string.h>
52 #include <wchar.h>
53 #include <errno.h>
54 #include <unistd.h>
55 #include <fcntl.h>
56 #include "un-namespace.h"
57 
58 #include "collate.h"
59 #include "setlocale.h"
60 #include "ldpart.h"
61 #include "libc_private.h"
62 
63 struct xlocale_collate __xlocale_global_collate = {
64 	{{0}, "C"}, 1, 0, 0, 0
65 };
66 
67 struct xlocale_collate __xlocale_C_collate = {
68 	{{0}, "C"}, 1, 0, 0, 0
69 };
70 
71 static int
72 __collate_load_tables_l(const char *encoding, struct xlocale_collate *table);
73 
74 static void
75 destruct_collate(void *t)
76 {
77 	struct xlocale_collate *table = t;
78 	if (table->map && (table->maplen > 0)) {
79 		(void) munmap(table->map, table->maplen);
80 	}
81 	free(t);
82 }
83 
84 void *
85 __collate_load(const char *encoding, __unused locale_t unused)
86 {
87 	if (strcmp(encoding, "C") == 0 || strcmp(encoding, "POSIX") == 0 ||
88 	    strncmp(encoding, "C.", 2) == 0) {
89 		return &__xlocale_C_collate;
90 	}
91 	struct xlocale_collate *table = calloc(sizeof(struct xlocale_collate), 1);
92 	table->header.header.destructor = destruct_collate;
93 	// FIXME: Make sure that _LDP_CACHE is never returned.  We should be doing
94 	// the caching outside of this section
95 	if (__collate_load_tables_l(encoding, table) != _LDP_LOADED) {
96 		xlocale_release(table);
97 		return NULL;
98 	}
99 	return table;
100 }
101 
102 /**
103  * Load the collation tables for the specified encoding into the global table.
104  */
105 int
106 __collate_load_tables(const char *encoding)
107 {
108 
109 	return (__collate_load_tables_l(encoding, &__xlocale_global_collate));
110 }
111 
112 static int
113 __collate_load_tables_l(const char *encoding, struct xlocale_collate *table)
114 {
115 	int i, chains, z;
116 	char *buf;
117 	char *TMP;
118 	char *map;
119 	collate_info_t *info;
120 	struct stat sbuf;
121 	int fd;
122 
123 	table->__collate_load_error = 1;
124 
125 	/* 'encoding' must be already checked. */
126 	if (strcmp(encoding, "C") == 0 || strcmp(encoding, "POSIX") == 0 ||
127 	    strncmp(encoding, "C.", 2) == 0) {
128 		return (_LDP_CACHE);
129 	}
130 
131 	if (asprintf(&buf, "%s/%s/LC_COLLATE", _PathLocale, encoding) == -1)
132 		return (_LDP_ERROR);
133 
134 	if ((fd = _open(buf, O_RDONLY | O_CLOEXEC)) < 0) {
135 		free(buf);
136 		return (_LDP_ERROR);
137 	}
138 	free(buf);
139 	if (_fstat(fd, &sbuf) < 0) {
140 		(void) _close(fd);
141 		return (_LDP_ERROR);
142 	}
143 	if (sbuf.st_size < (COLLATE_FMT_VERSION_LEN +
144 			    XLOCALE_DEF_VERSION_LEN +
145 			    sizeof (info))) {
146 		(void) _close(fd);
147 		errno = EINVAL;
148 		return (_LDP_ERROR);
149 	}
150 	map = mmap(NULL, sbuf.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
151 	(void) _close(fd);
152 	if ((TMP = map) == MAP_FAILED) {
153 		return (_LDP_ERROR);
154 	}
155 
156 	if (strncmp(TMP, COLLATE_FMT_VERSION, COLLATE_FMT_VERSION_LEN) != 0) {
157 		(void) munmap(map, sbuf.st_size);
158 		errno = EINVAL;
159 		return (_LDP_ERROR);
160 	}
161 	TMP += COLLATE_FMT_VERSION_LEN;
162 	strlcat(table->header.version, TMP, sizeof (table->header.version));
163 	TMP += XLOCALE_DEF_VERSION_LEN;
164 
165 	info = (void *)TMP;
166 	TMP += sizeof (*info);
167 
168 	if ((info->directive_count < 1) ||
169 	    (info->directive_count >= COLL_WEIGHTS_MAX) ||
170 	    ((chains = info->chain_count) < 0)) {
171 		(void) munmap(map, sbuf.st_size);
172 		errno = EINVAL;
173 		return (_LDP_ERROR);
174 	}
175 
176 	i = (sizeof (collate_char_t) * (UCHAR_MAX + 1)) +
177 	    (sizeof (collate_chain_t) * chains) +
178 	    (sizeof (collate_large_t) * info->large_count);
179 	for (z = 0; z < info->directive_count; z++) {
180 		i += sizeof (collate_subst_t) * info->subst_count[z];
181 	}
182 	if (i != (sbuf.st_size - (TMP - map))) {
183 		(void) munmap(map, sbuf.st_size);
184 		errno = EINVAL;
185 		return (_LDP_ERROR);
186 	}
187 
188 	if (table->map && (table->maplen > 0)) {
189 		(void) munmap(table->map, table->maplen);
190 	}
191 	table->map = map;
192 	table->maplen = sbuf.st_size;
193 	table->info = info;
194 	table->char_pri_table = (void *)TMP;
195 	TMP += sizeof (collate_char_t) * (UCHAR_MAX + 1);
196 
197 	for (z = 0; z < info->directive_count; z++) {
198 		if (info->subst_count[z] > 0) {
199 			table->subst_table[z] = (void *)TMP;
200 			TMP += info->subst_count[z] * sizeof (collate_subst_t);
201 		} else {
202 			table->subst_table[z] = NULL;
203 		}
204 	}
205 
206 	if (chains > 0) {
207 		table->chain_pri_table = (void *)TMP;
208 		TMP += chains * sizeof (collate_chain_t);
209 	} else
210 		table->chain_pri_table = NULL;
211 	if (info->large_count > 0)
212 		table->large_pri_table = (void *)TMP;
213 	else
214 		table->large_pri_table = NULL;
215 
216 	table->__collate_load_error = 0;
217 	return (_LDP_LOADED);
218 }
219 
220 static const int32_t *
221 substsearch(struct xlocale_collate *table, const wchar_t key, int pass)
222 {
223 	const collate_subst_t *p;
224 	int n = table->info->subst_count[pass];
225 
226 	if (n == 0)
227 		return (NULL);
228 
229 	if (pass >= table->info->directive_count)
230 		return (NULL);
231 
232 	if (!(key & COLLATE_SUBST_PRIORITY))
233 		return (NULL);
234 
235 	p = table->subst_table[pass] + (key & ~COLLATE_SUBST_PRIORITY);
236 	assert(p->key == key);
237 
238 	return (p->pri);
239 }
240 
241 static collate_chain_t *
242 chainsearch(struct xlocale_collate *table, const wchar_t *key, int *len)
243 {
244 	int low = 0;
245 	int high = table->info->chain_count - 1;
246 	int next, compar, l;
247 	collate_chain_t *p;
248 	collate_chain_t *tab = table->chain_pri_table;
249 
250 	if (high < 0)
251 		return (NULL);
252 
253 	while (low <= high) {
254 		next = (low + high) / 2;
255 		p = tab + next;
256 		compar = *key - *p->str;
257 		if (compar == 0) {
258 			l = wcsnlen(p->str, COLLATE_STR_LEN);
259 			compar = wcsncmp(key, p->str, l);
260 			if (compar == 0) {
261 				*len = l;
262 				return (p);
263 			}
264 		}
265 		if (compar > 0)
266 			low = next + 1;
267 		else
268 			high = next - 1;
269 	}
270 	return (NULL);
271 }
272 
273 static collate_large_t *
274 largesearch(struct xlocale_collate *table, const wchar_t key)
275 {
276 	int low = 0;
277 	int high = table->info->large_count - 1;
278 	int next, compar;
279 	collate_large_t *p;
280 	collate_large_t *tab = table->large_pri_table;
281 
282 	if (high < 0)
283 		return (NULL);
284 
285 	while (low <= high) {
286 		next = (low + high) / 2;
287 		p = tab + next;
288 		compar = key - p->val;
289 		if (compar == 0)
290 			return (p);
291 		if (compar > 0)
292 			low = next + 1;
293 		else
294 			high = next - 1;
295 	}
296 	return (NULL);
297 }
298 
299 void
300 _collate_lookup(struct xlocale_collate *table, const wchar_t *t, int *len,
301     int *pri, int which, const int **state)
302 {
303 	collate_chain_t *p2;
304 	collate_large_t *match;
305 	int p, l;
306 	const int *sptr;
307 
308 	/*
309 	 * If this is the "last" pass for the UNDEFINED, then
310 	 * we just return the priority itself.
311 	 */
312 	if (which >= table->info->directive_count) {
313 		*pri = *t;
314 		*len = 1;
315 		*state = NULL;
316 		return;
317 	}
318 
319 	/*
320 	 * If we have remaining substitution data from a previous
321 	 * call, consume it first.
322 	 */
323 	if ((sptr = *state) != NULL) {
324 		*pri = *sptr;
325 		sptr++;
326 		if ((sptr == *state) || (sptr == NULL))
327 			*state = NULL;
328 		else
329 			*state = sptr;
330 		*len = 0;
331 		return;
332 	}
333 
334 	/* No active substitutions */
335 	*len = 1;
336 
337 	/*
338 	 * Check for composites such as diphthongs that collate as a
339 	 * single element (aka chains or collating-elements).
340 	 */
341 	if (((p2 = chainsearch(table, t, &l)) != NULL) &&
342 	    ((p = p2->pri[which]) >= 0)) {
343 
344 		*len = l;
345 		*pri = p;
346 
347 	} else if (*t <= UCHAR_MAX) {
348 
349 		/*
350 		 * Character is a small (8-bit) character.
351 		 * We just look these up directly for speed.
352 		 */
353 		*pri = table->char_pri_table[*t].pri[which];
354 
355 	} else if ((table->info->large_count > 0) &&
356 	    ((match = largesearch(table, *t)) != NULL)) {
357 
358 		/*
359 		 * Character was found in the extended table.
360 		 */
361 		*pri = match->pri.pri[which];
362 
363 	} else {
364 		/*
365 		 * Character lacks a specific definition.
366 		 */
367 		if (table->info->directive[which] & DIRECTIVE_UNDEFINED) {
368 			/* Mask off sign bit to prevent ordering confusion. */
369 			*pri = (*t & COLLATE_MAX_PRIORITY);
370 		} else {
371 			*pri = table->info->undef_pri[which];
372 		}
373 		/* No substitutions for undefined characters! */
374 		return;
375 	}
376 
377 	/*
378 	 * Try substituting (expanding) the character.  We are
379 	 * currently doing this *after* the chain compression.  I
380 	 * think it should not matter, but this way might be slightly
381 	 * faster.
382 	 *
383 	 * We do this after the priority search, as this will help us
384 	 * to identify a single key value.  In order for this to work,
385 	 * its important that the priority assigned to a given element
386 	 * to be substituted be unique for that level.  The localedef
387 	 * code ensures this for us.
388 	 */
389 	if ((sptr = substsearch(table, *pri, which)) != NULL) {
390 		if ((*pri = *sptr) > 0) {
391 			sptr++;
392 			*state = *sptr ? sptr : NULL;
393 		}
394 	}
395 
396 }
397 
398 /*
399  * This is the meaty part of wcsxfrm & strxfrm.  Note that it does
400  * NOT NULL terminate.  That is left to the caller.
401  */
402 size_t
403 _collate_wxfrm(struct xlocale_collate *table, const wchar_t *src, wchar_t *xf,
404     size_t room)
405 {
406 	int		pri;
407 	int		len;
408 	const wchar_t	*t;
409 	wchar_t		*tr = NULL;
410 	int		direc;
411 	int		pass;
412 	const int32_t 	*state;
413 	size_t		want = 0;
414 	size_t		need = 0;
415 	int		ndir = table->info->directive_count;
416 
417 	assert(src);
418 
419 	for (pass = 0; pass <= ndir; pass++) {
420 
421 		state = NULL;
422 
423 		if (pass != 0) {
424 			/* insert level separator from the previous pass */
425 			if (room) {
426 				*xf++ = 1;
427 				room--;
428 			}
429 			want++;
430 		}
431 
432 		/* special pass for undefined */
433 		if (pass == ndir) {
434 			direc = DIRECTIVE_FORWARD | DIRECTIVE_UNDEFINED;
435 		} else {
436 			direc = table->info->directive[pass];
437 		}
438 
439 		t = src;
440 
441 		if (direc & DIRECTIVE_BACKWARD) {
442 			wchar_t *bp, *fp, c;
443 			free(tr);
444 			if ((tr = wcsdup(t)) == NULL) {
445 				errno = ENOMEM;
446 				goto fail;
447 			}
448 			bp = tr;
449 			fp = tr + wcslen(tr) - 1;
450 			while (bp < fp) {
451 				c = *bp;
452 				*bp++ = *fp;
453 				*fp-- = c;
454 			}
455 			t = (const wchar_t *)tr;
456 		}
457 
458 		if (direc & DIRECTIVE_POSITION) {
459 			while (*t || state) {
460 				_collate_lookup(table, t, &len, &pri, pass, &state);
461 				t += len;
462 				if (pri <= 0) {
463 					if (pri < 0) {
464 						errno = EINVAL;
465 						goto fail;
466 					}
467 					state = NULL;
468 					pri = COLLATE_MAX_PRIORITY;
469 				}
470 				if (room) {
471 					*xf++ = pri;
472 					room--;
473 				}
474 				want++;
475 				need = want;
476 			}
477 		} else {
478 			while (*t || state) {
479 				_collate_lookup(table, t, &len, &pri, pass, &state);
480 				t += len;
481 				if (pri <= 0) {
482 					if (pri < 0) {
483 						errno = EINVAL;
484 						goto fail;
485 					}
486 					state = NULL;
487 					continue;
488 				}
489 				if (room) {
490 					*xf++ = pri;
491 					room--;
492 				}
493 				want++;
494 				need = want;
495 			}
496 		}
497 	}
498 	free(tr);
499 	return (need);
500 
501 fail:
502 	free(tr);
503 	return ((size_t)(-1));
504 }
505 
506 /*
507  * In the non-POSIX case, we transform each character into a string of
508  * characters representing the character's priority.  Since char is usually
509  * signed, we are limited by 7 bits per byte.  To avoid zero, we need to add
510  * XFRM_OFFSET, so we can't use a full 7 bits.  For simplicity, we choose 6
511  * bits per byte.
512  *
513  * It turns out that we sometimes have real priorities that are
514  * 31-bits wide.  (But: be careful using priorities where the high
515  * order bit is set -- i.e. the priority is negative.  The sort order
516  * may be surprising!)
517  *
518  * TODO: This would be a good area to optimize somewhat.  It turns out
519  * that real prioririties *except for the last UNDEFINED pass* are generally
520  * very small.  We need the localedef code to precalculate the max
521  * priority for us, and ideally also give us a mask, and then we could
522  * severely limit what we expand to.
523  */
524 #define	XFRM_BYTES	6
525 #define	XFRM_OFFSET	('0')	/* make all printable characters */
526 #define	XFRM_SHIFT	6
527 #define	XFRM_MASK	((1 << XFRM_SHIFT) - 1)
528 #define	XFRM_SEP	('.')	/* chosen to be less than XFRM_OFFSET */
529 
530 static int
531 xfrm(struct xlocale_collate *table, unsigned char *p, int pri, int pass)
532 {
533 	/* we use unsigned to ensure zero fill on right shift */
534 	uint32_t val = (uint32_t)table->info->pri_count[pass];
535 	int nc = 0;
536 
537 	while (val) {
538 		*p = (pri & XFRM_MASK) + XFRM_OFFSET;
539 		pri >>= XFRM_SHIFT;
540 		val >>= XFRM_SHIFT;
541 		p++;
542 		nc++;
543 	}
544 	return (nc);
545 }
546 
547 size_t
548 _collate_sxfrm(struct xlocale_collate *table, const wchar_t *src, char *xf,
549     size_t room)
550 {
551 	int		pri;
552 	int		len;
553 	const wchar_t	*t;
554 	wchar_t		*tr = NULL;
555 	int		direc;
556 	int		pass;
557 	const int32_t 	*state;
558 	size_t		want = 0;
559 	size_t		need = 0;
560 	int		b;
561 	uint8_t		buf[XFRM_BYTES];
562 	int		ndir = table->info->directive_count;
563 
564 	assert(src);
565 
566 	for (pass = 0; pass <= ndir; pass++) {
567 
568 		state = NULL;
569 
570 		if (pass != 0) {
571 			/* insert level separator from the previous pass */
572 			if (room) {
573 				*xf++ = XFRM_SEP;
574 				room--;
575 			}
576 			want++;
577 		}
578 
579 		/* special pass for undefined */
580 		if (pass == ndir) {
581 			direc = DIRECTIVE_FORWARD | DIRECTIVE_UNDEFINED;
582 		} else {
583 			direc = table->info->directive[pass];
584 		}
585 
586 		t = src;
587 
588 		if (direc & DIRECTIVE_BACKWARD) {
589 			wchar_t *bp, *fp, c;
590 			free(tr);
591 			if ((tr = wcsdup(t)) == NULL) {
592 				errno = ENOMEM;
593 				goto fail;
594 			}
595 			bp = tr;
596 			fp = tr + wcslen(tr) - 1;
597 			while (bp < fp) {
598 				c = *bp;
599 				*bp++ = *fp;
600 				*fp-- = c;
601 			}
602 			t = (const wchar_t *)tr;
603 		}
604 
605 		if (direc & DIRECTIVE_POSITION) {
606 			while (*t || state) {
607 
608 				_collate_lookup(table, t, &len, &pri, pass, &state);
609 				t += len;
610 				if (pri <= 0) {
611 					if (pri < 0) {
612 						errno = EINVAL;
613 						goto fail;
614 					}
615 					state = NULL;
616 					pri = COLLATE_MAX_PRIORITY;
617 				}
618 
619 				b = xfrm(table, buf, pri, pass);
620 				want += b;
621 				if (room) {
622 					while (b) {
623 						b--;
624 						if (room) {
625 							*xf++ = buf[b];
626 							room--;
627 						}
628 					}
629 				}
630 				need = want;
631 			}
632 		} else {
633 			while (*t || state) {
634 				_collate_lookup(table, t, &len, &pri, pass, &state);
635 				t += len;
636 				if (pri <= 0) {
637 					if (pri < 0) {
638 						errno = EINVAL;
639 						goto fail;
640 					}
641 					state = NULL;
642 					continue;
643 				}
644 
645 				b = xfrm(table, buf, pri, pass);
646 				want += b;
647 				if (room) {
648 
649 					while (b) {
650 						b--;
651 						if (room) {
652 							*xf++ = buf[b];
653 							room--;
654 						}
655 					}
656 				}
657 				need = want;
658 			}
659 		}
660 	}
661 	free(tr);
662 	return (need);
663 
664 fail:
665 	free(tr);
666 	return ((size_t)(-1));
667 }
668 
669 /*
670  * __collate_equiv_value returns the primary collation value for the given
671  * collating symbol specified by str and len.  Zero or negative is returned
672  * if the collating symbol was not found.  This function is used by bracket
673  * code in the TRE regex library.
674  */
675 int
676 __collate_equiv_value(locale_t locale, const wchar_t *str, size_t len)
677 {
678 	int32_t e;
679 
680 	if (len < 1 || len >= COLLATE_STR_LEN)
681 		return (-1);
682 
683 	FIX_LOCALE(locale);
684 	struct xlocale_collate *table =
685 		(struct xlocale_collate*)locale->components[XLC_COLLATE];
686 
687 	if (table->__collate_load_error)
688 		return ((len == 1 && *str <= UCHAR_MAX) ? *str : -1);
689 
690 	if (len == 1) {
691 		e = -1;
692 		if (*str <= UCHAR_MAX)
693 			e = table->char_pri_table[*str].pri[0];
694 		else if (table->info->large_count > 0) {
695 			collate_large_t *match_large;
696 			match_large = largesearch(table, *str);
697 			if (match_large)
698 				e = match_large->pri.pri[0];
699 		}
700 		if (e == 0)
701 			return (1);
702 		return (e > 0 ? e : 0);
703 	}
704 	if (table->info->chain_count > 0) {
705 		wchar_t name[COLLATE_STR_LEN];
706 		collate_chain_t *match_chain;
707 		int clen;
708 
709 		wcsncpy (name, str, len);
710 		name[len] = 0;
711 		match_chain = chainsearch(table, name, &clen);
712 		if (match_chain) {
713 			e = match_chain->pri[0];
714 			if (e == 0)
715 				return (1);
716 			return (e < 0 ? -e : e);
717 		}
718 	}
719 	return (0);
720 }
721