xref: /freebsd/lib/libc/locale/collate.c (revision a134ebd6e63f658f2d3d04ac0c60d23bcaa86dd7)
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)) < 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_STR_LEN + sizeof (info))) {
144 		(void) _close(fd);
145 		errno = EINVAL;
146 		return (_LDP_ERROR);
147 	}
148 	map = mmap(NULL, sbuf.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
149 	(void) _close(fd);
150 	if ((TMP = map) == MAP_FAILED) {
151 		return (_LDP_ERROR);
152 	}
153 
154 	if (strncmp(TMP, COLLATE_VERSION, COLLATE_STR_LEN) != 0) {
155 		(void) munmap(map, sbuf.st_size);
156 		errno = EINVAL;
157 		return (_LDP_ERROR);
158 	}
159 	TMP += COLLATE_STR_LEN;
160 
161 	info = (void *)TMP;
162 	TMP += sizeof (*info);
163 
164 	if ((info->directive_count < 1) ||
165 	    (info->directive_count >= COLL_WEIGHTS_MAX) ||
166 	    ((chains = info->chain_count) < 0)) {
167 		(void) munmap(map, sbuf.st_size);
168 		errno = EINVAL;
169 		return (_LDP_ERROR);
170 	}
171 
172 	i = (sizeof (collate_char_t) * (UCHAR_MAX + 1)) +
173 	    (sizeof (collate_chain_t) * chains) +
174 	    (sizeof (collate_large_t) * info->large_count);
175 	for (z = 0; z < info->directive_count; z++) {
176 		i += sizeof (collate_subst_t) * info->subst_count[z];
177 	}
178 	if (i != (sbuf.st_size - (TMP - map))) {
179 		(void) munmap(map, sbuf.st_size);
180 		errno = EINVAL;
181 		return (_LDP_ERROR);
182 	}
183 
184 	if (table->map && (table->maplen > 0)) {
185 		(void) munmap(table->map, table->maplen);
186 	}
187 	table->map = map;
188 	table->maplen = sbuf.st_size;
189 	table->info = info;
190 	table->char_pri_table = (void *)TMP;
191 	TMP += sizeof (collate_char_t) * (UCHAR_MAX + 1);
192 
193 	for (z = 0; z < info->directive_count; z++) {
194 		if (info->subst_count[z] > 0) {
195 			table->subst_table[z] = (void *)TMP;
196 			TMP += info->subst_count[z] * sizeof (collate_subst_t);
197 		} else {
198 			table->subst_table[z] = NULL;
199 		}
200 	}
201 
202 	if (chains > 0) {
203 		table->chain_pri_table = (void *)TMP;
204 		TMP += chains * sizeof (collate_chain_t);
205 	} else
206 		table->chain_pri_table = NULL;
207 	if (info->large_count > 0)
208 		table->large_pri_table = (void *)TMP;
209 	else
210 		table->large_pri_table = NULL;
211 
212 	table->__collate_load_error = 0;
213 	return (_LDP_LOADED);
214 }
215 
216 static const int32_t *
217 substsearch(struct xlocale_collate *table, const wchar_t key, int pass)
218 {
219 	const collate_subst_t *p;
220 	int n = table->info->subst_count[pass];
221 
222 	if (n == 0)
223 		return (NULL);
224 
225 	if (pass >= table->info->directive_count)
226 		return (NULL);
227 
228 	if (!(key & COLLATE_SUBST_PRIORITY))
229 		return (NULL);
230 
231 	p = table->subst_table[pass] + (key & ~COLLATE_SUBST_PRIORITY);
232 	assert(p->key == key);
233 
234 	return (p->pri);
235 }
236 
237 static collate_chain_t *
238 chainsearch(struct xlocale_collate *table, const wchar_t *key, int *len)
239 {
240 	int low = 0;
241 	int high = table->info->chain_count - 1;
242 	int next, compar, l;
243 	collate_chain_t *p;
244 	collate_chain_t *tab = table->chain_pri_table;
245 
246 	if (high < 0)
247 		return (NULL);
248 
249 	while (low <= high) {
250 		next = (low + high) / 2;
251 		p = tab + next;
252 		compar = *key - *p->str;
253 		if (compar == 0) {
254 			l = wcsnlen(p->str, COLLATE_STR_LEN);
255 			compar = wcsncmp(key, p->str, l);
256 			if (compar == 0) {
257 				*len = l;
258 				return (p);
259 			}
260 		}
261 		if (compar > 0)
262 			low = next + 1;
263 		else
264 			high = next - 1;
265 	}
266 	return (NULL);
267 }
268 
269 static collate_large_t *
270 largesearch(struct xlocale_collate *table, const wchar_t key)
271 {
272 	int low = 0;
273 	int high = table->info->large_count - 1;
274 	int next, compar;
275 	collate_large_t *p;
276 	collate_large_t *tab = table->large_pri_table;
277 
278 	if (high < 0)
279 		return (NULL);
280 
281 	while (low <= high) {
282 		next = (low + high) / 2;
283 		p = tab + next;
284 		compar = key - p->val;
285 		if (compar == 0)
286 			return (p);
287 		if (compar > 0)
288 			low = next + 1;
289 		else
290 			high = next - 1;
291 	}
292 	return (NULL);
293 }
294 
295 void
296 _collate_lookup(struct xlocale_collate *table, const wchar_t *t, int *len,
297     int *pri, int which, const int **state)
298 {
299 	collate_chain_t *p2;
300 	collate_large_t *match;
301 	int p, l;
302 	const int *sptr;
303 
304 	/*
305 	 * If this is the "last" pass for the UNDEFINED, then
306 	 * we just return the priority itself.
307 	 */
308 	if (which >= table->info->directive_count) {
309 		*pri = *t;
310 		*len = 1;
311 		*state = NULL;
312 		return;
313 	}
314 
315 	/*
316 	 * If we have remaining substitution data from a previous
317 	 * call, consume it first.
318 	 */
319 	if ((sptr = *state) != NULL) {
320 		*pri = *sptr;
321 		sptr++;
322 		if ((sptr == *state) || (sptr == NULL))
323 			*state = NULL;
324 		else
325 			*state = sptr;
326 		*len = 0;
327 		return;
328 	}
329 
330 	/* No active substitutions */
331 	*len = 1;
332 
333 	/*
334 	 * Check for composites such as diphthongs that collate as a
335 	 * single element (aka chains or collating-elements).
336 	 */
337 	if (((p2 = chainsearch(table, t, &l)) != NULL) &&
338 	    ((p = p2->pri[which]) >= 0)) {
339 
340 		*len = l;
341 		*pri = p;
342 
343 	} else if (*t <= UCHAR_MAX) {
344 
345 		/*
346 		 * Character is a small (8-bit) character.
347 		 * We just look these up directly for speed.
348 		 */
349 		*pri = table->char_pri_table[*t].pri[which];
350 
351 	} else if ((table->info->large_count > 0) &&
352 	    ((match = largesearch(table, *t)) != NULL)) {
353 
354 		/*
355 		 * Character was found in the extended table.
356 		 */
357 		*pri = match->pri.pri[which];
358 
359 	} else {
360 		/*
361 		 * Character lacks a specific definition.
362 		 */
363 		if (table->info->directive[which] & DIRECTIVE_UNDEFINED) {
364 			/* Mask off sign bit to prevent ordering confusion. */
365 			*pri = (*t & COLLATE_MAX_PRIORITY);
366 		} else {
367 			*pri = table->info->undef_pri[which];
368 		}
369 		/* No substitutions for undefined characters! */
370 		return;
371 	}
372 
373 	/*
374 	 * Try substituting (expanding) the character.  We are
375 	 * currently doing this *after* the chain compression.  I
376 	 * think it should not matter, but this way might be slightly
377 	 * faster.
378 	 *
379 	 * We do this after the priority search, as this will help us
380 	 * to identify a single key value.  In order for this to work,
381 	 * its important that the priority assigned to a given element
382 	 * to be substituted be unique for that level.  The localedef
383 	 * code ensures this for us.
384 	 */
385 	if ((sptr = substsearch(table, *pri, which)) != NULL) {
386 		if ((*pri = *sptr) > 0) {
387 			sptr++;
388 			*state = *sptr ? sptr : NULL;
389 		}
390 	}
391 
392 }
393 
394 /*
395  * This is the meaty part of wcsxfrm & strxfrm.  Note that it does
396  * NOT NULL terminate.  That is left to the caller.
397  */
398 size_t
399 _collate_wxfrm(struct xlocale_collate *table, const wchar_t *src, wchar_t *xf,
400     size_t room)
401 {
402 	int		pri;
403 	int		len;
404 	const wchar_t	*t;
405 	wchar_t		*tr = NULL;
406 	int		direc;
407 	int		pass;
408 	const int32_t 	*state;
409 	size_t		want = 0;
410 	size_t		need = 0;
411 	int		ndir = table->info->directive_count;
412 
413 	assert(src);
414 
415 	for (pass = 0; pass <= ndir; pass++) {
416 
417 		state = NULL;
418 
419 		if (pass != 0) {
420 			/* insert level separator from the previous pass */
421 			if (room) {
422 				*xf++ = 1;
423 				room--;
424 			}
425 			want++;
426 		}
427 
428 		/* special pass for undefined */
429 		if (pass == ndir) {
430 			direc = DIRECTIVE_FORWARD | DIRECTIVE_UNDEFINED;
431 		} else {
432 			direc = table->info->directive[pass];
433 		}
434 
435 		t = src;
436 
437 		if (direc & DIRECTIVE_BACKWARD) {
438 			wchar_t *bp, *fp, c;
439 			free(tr);
440 			if ((tr = wcsdup(t)) == NULL) {
441 				errno = ENOMEM;
442 				goto fail;
443 			}
444 			bp = tr;
445 			fp = tr + wcslen(tr) - 1;
446 			while (bp < fp) {
447 				c = *bp;
448 				*bp++ = *fp;
449 				*fp-- = c;
450 			}
451 			t = (const wchar_t *)tr;
452 		}
453 
454 		if (direc & DIRECTIVE_POSITION) {
455 			while (*t || state) {
456 				_collate_lookup(table, t, &len, &pri, pass, &state);
457 				t += len;
458 				if (pri <= 0) {
459 					if (pri < 0) {
460 						errno = EINVAL;
461 						goto fail;
462 					}
463 					state = NULL;
464 					pri = COLLATE_MAX_PRIORITY;
465 				}
466 				if (room) {
467 					*xf++ = pri;
468 					room--;
469 				}
470 				want++;
471 				need = want;
472 			}
473 		} else {
474 			while (*t || state) {
475 				_collate_lookup(table, t, &len, &pri, pass, &state);
476 				t += len;
477 				if (pri <= 0) {
478 					if (pri < 0) {
479 						errno = EINVAL;
480 						goto fail;
481 					}
482 					state = NULL;
483 					continue;
484 				}
485 				if (room) {
486 					*xf++ = pri;
487 					room--;
488 				}
489 				want++;
490 				need = want;
491 			}
492 		}
493 	}
494 	free(tr);
495 	return (need);
496 
497 fail:
498 	free(tr);
499 	return ((size_t)(-1));
500 }
501 
502 /*
503  * In the non-POSIX case, we transform each character into a string of
504  * characters representing the character's priority.  Since char is usually
505  * signed, we are limited by 7 bits per byte.  To avoid zero, we need to add
506  * XFRM_OFFSET, so we can't use a full 7 bits.  For simplicity, we choose 6
507  * bits per byte.
508  *
509  * It turns out that we sometimes have real priorities that are
510  * 31-bits wide.  (But: be careful using priorities where the high
511  * order bit is set -- i.e. the priority is negative.  The sort order
512  * may be surprising!)
513  *
514  * TODO: This would be a good area to optimize somewhat.  It turns out
515  * that real prioririties *except for the last UNDEFINED pass* are generally
516  * very small.  We need the localedef code to precalculate the max
517  * priority for us, and ideally also give us a mask, and then we could
518  * severely limit what we expand to.
519  */
520 #define	XFRM_BYTES	6
521 #define	XFRM_OFFSET	('0')	/* make all printable characters */
522 #define	XFRM_SHIFT	6
523 #define	XFRM_MASK	((1 << XFRM_SHIFT) - 1)
524 #define	XFRM_SEP	('.')	/* chosen to be less than XFRM_OFFSET */
525 
526 static int
527 xfrm(struct xlocale_collate *table, unsigned char *p, int pri, int pass)
528 {
529 	/* we use unsigned to ensure zero fill on right shift */
530 	uint32_t val = (uint32_t)table->info->pri_count[pass];
531 	int nc = 0;
532 
533 	while (val) {
534 		*p = (pri & XFRM_MASK) + XFRM_OFFSET;
535 		pri >>= XFRM_SHIFT;
536 		val >>= XFRM_SHIFT;
537 		p++;
538 		nc++;
539 	}
540 	return (nc);
541 }
542 
543 size_t
544 _collate_sxfrm(struct xlocale_collate *table, const wchar_t *src, char *xf,
545     size_t room)
546 {
547 	int		pri;
548 	int		len;
549 	const wchar_t	*t;
550 	wchar_t		*tr = NULL;
551 	int		direc;
552 	int		pass;
553 	const int32_t 	*state;
554 	size_t		want = 0;
555 	size_t		need = 0;
556 	int		b;
557 	uint8_t		buf[XFRM_BYTES];
558 	int		ndir = table->info->directive_count;
559 
560 	assert(src);
561 
562 	for (pass = 0; pass <= ndir; pass++) {
563 
564 		state = NULL;
565 
566 		if (pass != 0) {
567 			/* insert level separator from the previous pass */
568 			if (room) {
569 				*xf++ = XFRM_SEP;
570 				room--;
571 			}
572 			want++;
573 		}
574 
575 		/* special pass for undefined */
576 		if (pass == ndir) {
577 			direc = DIRECTIVE_FORWARD | DIRECTIVE_UNDEFINED;
578 		} else {
579 			direc = table->info->directive[pass];
580 		}
581 
582 		t = src;
583 
584 		if (direc & DIRECTIVE_BACKWARD) {
585 			wchar_t *bp, *fp, c;
586 			free(tr);
587 			if ((tr = wcsdup(t)) == NULL) {
588 				errno = ENOMEM;
589 				goto fail;
590 			}
591 			bp = tr;
592 			fp = tr + wcslen(tr) - 1;
593 			while (bp < fp) {
594 				c = *bp;
595 				*bp++ = *fp;
596 				*fp-- = c;
597 			}
598 			t = (const wchar_t *)tr;
599 		}
600 
601 		if (direc & DIRECTIVE_POSITION) {
602 			while (*t || state) {
603 
604 				_collate_lookup(table, t, &len, &pri, pass, &state);
605 				t += len;
606 				if (pri <= 0) {
607 					if (pri < 0) {
608 						errno = EINVAL;
609 						goto fail;
610 					}
611 					state = NULL;
612 					pri = COLLATE_MAX_PRIORITY;
613 				}
614 
615 				b = xfrm(table, buf, pri, pass);
616 				want += b;
617 				if (room) {
618 					while (b) {
619 						b--;
620 						if (room) {
621 							*xf++ = buf[b];
622 							room--;
623 						}
624 					}
625 				}
626 				need = want;
627 			}
628 		} else {
629 			while (*t || state) {
630 				_collate_lookup(table, t, &len, &pri, pass, &state);
631 				t += len;
632 				if (pri <= 0) {
633 					if (pri < 0) {
634 						errno = EINVAL;
635 						goto fail;
636 					}
637 					state = NULL;
638 					continue;
639 				}
640 
641 				b = xfrm(table, buf, pri, pass);
642 				want += b;
643 				if (room) {
644 
645 					while (b) {
646 						b--;
647 						if (room) {
648 							*xf++ = buf[b];
649 							room--;
650 						}
651 					}
652 				}
653 				need = want;
654 			}
655 		}
656 	}
657 	free(tr);
658 	return (need);
659 
660 fail:
661 	free(tr);
662 	return ((size_t)(-1));
663 }
664 
665 /*
666  * __collate_equiv_value returns the primary collation value for the given
667  * collating symbol specified by str and len.  Zero or negative is returned
668  * if the collating symbol was not found.  This function is used by bracket
669  * code in the TRE regex library.
670  */
671 int
672 __collate_equiv_value(locale_t locale, const wchar_t *str, size_t len)
673 {
674 	int32_t e;
675 
676 	if (len < 1 || len >= COLLATE_STR_LEN)
677 		return (-1);
678 
679 	FIX_LOCALE(locale);
680 	struct xlocale_collate *table =
681 		(struct xlocale_collate*)locale->components[XLC_COLLATE];
682 
683 	if (table->__collate_load_error)
684 		return ((len == 1 && *str <= UCHAR_MAX) ? *str : -1);
685 
686 	if (len == 1) {
687 		e = -1;
688 		if (*str <= UCHAR_MAX)
689 			e = table->char_pri_table[*str].pri[0];
690 		else if (table->info->large_count > 0) {
691 			collate_large_t *match_large;
692 			match_large = largesearch(table, *str);
693 			if (match_large)
694 				e = match_large->pri.pri[0];
695 		}
696 		if (e == 0)
697 			return (1);
698 		return (e > 0 ? e : 0);
699 	}
700 	if (table->info->chain_count > 0) {
701 		wchar_t name[COLLATE_STR_LEN];
702 		collate_chain_t *match_chain;
703 		int clen;
704 
705 		wcsncpy (name, str, len);
706 		name[len] = 0;
707 		match_chain = chainsearch(table, name, &clen);
708 		if (match_chain) {
709 			e = match_chain->pri[0];
710 			if (e == 0)
711 				return (1);
712 			return (e < 0 ? -e : e);
713 		}
714 	}
715 	return (0);
716 }
717