1// © 2016 and later: Unicode, Inc. and others.
2// License & terms of use: http://www.unicode.org/copyright.html
3/*
4**********************************************************************
5* Copyright (c) 2002-2014, International Business Machines Corporation
6* and others. All Rights Reserved.
7**********************************************************************
8* Date Name Description
9* 01/14/2002 aliu Creation.
10**********************************************************************
11*/
12
13#include "unicode/utypes.h"
14
15#if !UCONFIG_NO_TRANSLITERATION
16
17#include "tridpars.h"
18#include "hash.h"
19#include "mutex.h"
20#include "transreg.h"
21#include "uassert.h"
22#include "ucln_in.h"
23#include "unicode/parsepos.h"
24#include "unicode/translit.h"
25#include "unicode/uchar.h"
26#include "unicode/uniset.h"
27#include "unicode/unistr.h"
28#include "unicode/utrans.h"
29#include "util.h"
30#include "uvector.h"
31
32U_NAMESPACE_BEGIN
33
34static const UChar ID_DELIM = 0x003B; // ;
35static const UChar TARGET_SEP = 0x002D; // -
36static const UChar VARIANT_SEP = 0x002F; // /
37static const UChar OPEN_REV = 0x0028; // (
38static const UChar CLOSE_REV = 0x0029; // )
39
40//static const UChar EMPTY[] = {0}; // ""
41static const UChar ANY[] = {65,110,121,0}; // "Any"
42static const UChar ANY_NULL[] = {65,110,121,45,78,117,108,108,0}; // "Any-Null"
43
44static const int32_t FORWARD = UTRANS_FORWARD;
45static const int32_t REVERSE = UTRANS_REVERSE;
46
47static Hashtable* SPECIAL_INVERSES = NULL;
48static UInitOnce gSpecialInversesInitOnce = U_INITONCE_INITIALIZER;
49
50/**
51 * The mutex controlling access to SPECIAL_INVERSES
52 */
53static UMutex LOCK;
54
55TransliteratorIDParser::Specs::Specs(const UnicodeString& s, const UnicodeString& t,
56 const UnicodeString& v, UBool sawS,
57 const UnicodeString& f) {
58 source = s;
59 target = t;
60 variant = v;
61 sawSource = sawS;
62 filter = f;
63}
64
65TransliteratorIDParser::SingleID::SingleID(const UnicodeString& c, const UnicodeString& b,
66 const UnicodeString& f) {
67 canonID = c;
68 basicID = b;
69 filter = f;
70}
71
72TransliteratorIDParser::SingleID::SingleID(const UnicodeString& c, const UnicodeString& b) {
73 canonID = c;
74 basicID = b;
75}
76
77Transliterator* TransliteratorIDParser::SingleID::createInstance() {
78 Transliterator* t;
79 if (basicID.length() == 0) {
80 t = createBasicInstance(UnicodeString(TRUE, ANY_NULL, 8), &canonID);
81 } else {
82 t = createBasicInstance(basicID, &canonID);
83 }
84 if (t != NULL) {
85 if (filter.length() != 0) {
86 UErrorCode ec = U_ZERO_ERROR;
87 UnicodeSet *set = new UnicodeSet(filter, ec);
88 if (U_FAILURE(ec)) {
89 delete set;
90 } else {
91 t->adoptFilter(set);
92 }
93 }
94 }
95 return t;
96}
97
98
99/**
100 * Parse a single ID, that is, an ID of the general form
101 * "[f1] s1-t1/v1 ([f2] s2-t3/v2)", with the parenthesized element
102 * optional, the filters optional, and the variants optional.
103 * @param id the id to be parsed
104 * @param pos INPUT-OUTPUT parameter. On input, the position of
105 * the first character to parse. On output, the position after
106 * the last character parsed.
107 * @param dir the direction. If the direction is REVERSE then the
108 * SingleID is constructed for the reverse direction.
109 * @return a SingleID object or NULL
110 */
111TransliteratorIDParser::SingleID*
112TransliteratorIDParser::parseSingleID(const UnicodeString& id, int32_t& pos,
113 int32_t dir, UErrorCode& status) {
114
115 int32_t start = pos;
116
117 // The ID will be of the form A, A(), A(B), or (B), where
118 // A and B are filter IDs.
119 Specs* specsA = NULL;
120 Specs* specsB = NULL;
121 UBool sawParen = FALSE;
122
123 // On the first pass, look for (B) or (). If this fails, then
124 // on the second pass, look for A, A(B), or A().
125 for (int32_t pass=1; pass<=2; ++pass) {
126 if (pass == 2) {
127 specsA = parseFilterID(id, pos, TRUE);
128 if (specsA == NULL) {
129 pos = start;
130 return NULL;
131 }
132 }
133 if (ICU_Utility::parseChar(id, pos, OPEN_REV)) {
134 sawParen = TRUE;
135 if (!ICU_Utility::parseChar(id, pos, CLOSE_REV)) {
136 specsB = parseFilterID(id, pos, TRUE);
137 // Must close with a ')'
138 if (specsB == NULL || !ICU_Utility::parseChar(id, pos, CLOSE_REV)) {
139 delete specsA;
140 pos = start;
141 return NULL;
142 }
143 }
144 break;
145 }
146 }
147
148 // Assemble return results
149 SingleID* single;
150 if (sawParen) {
151 if (dir == FORWARD) {
152 SingleID* b = specsToID(specsB, FORWARD);
153 single = specsToID(specsA, FORWARD);
154 // Null pointers check
155 if (b == NULL || single == NULL) {
156 delete b;
157 delete single;
158 status = U_MEMORY_ALLOCATION_ERROR;
159 return NULL;
160 }
161 single->canonID.append(OPEN_REV)
162 .append(b->canonID).append(CLOSE_REV);
163 if (specsA != NULL) {
164 single->filter = specsA->filter;
165 }
166 delete b;
167 } else {
168 SingleID* a = specsToID(specsA, FORWARD);
169 single = specsToID(specsB, FORWARD);
170 // Check for null pointer.
171 if (a == NULL || single == NULL) {
172 delete a;
173 delete single;
174 status = U_MEMORY_ALLOCATION_ERROR;
175 return NULL;
176 }
177 single->canonID.append(OPEN_REV)
178 .append(a->canonID).append(CLOSE_REV);
179 if (specsB != NULL) {
180 single->filter = specsB->filter;
181 }
182 delete a;
183 }
184 } else {
185 // assert(specsA != NULL);
186 if (dir == FORWARD) {
187 single = specsToID(specsA, FORWARD);
188 } else {
189 single = specsToSpecialInverse(*specsA, status);
190 if (single == NULL) {
191 single = specsToID(specsA, REVERSE);
192 }
193 }
194 // Check for NULL pointer
195 if (single == NULL) {
196 status = U_MEMORY_ALLOCATION_ERROR;
197 return NULL;
198 }
199 single->filter = specsA->filter;
200 }
201
202 delete specsA;
203 delete specsB;
204
205 return single;
206}
207
208/**
209 * Parse a filter ID, that is, an ID of the general form
210 * "[f1] s1-t1/v1", with the filters optional, and the variants optional.
211 * @param id the id to be parsed
212 * @param pos INPUT-OUTPUT parameter. On input, the position of
213 * the first character to parse. On output, the position after
214 * the last character parsed.
215 * @return a SingleID object or null if the parse fails
216 */
217TransliteratorIDParser::SingleID*
218TransliteratorIDParser::parseFilterID(const UnicodeString& id, int32_t& pos) {
219
220 int32_t start = pos;
221
222 Specs* specs = parseFilterID(id, pos, TRUE);
223 if (specs == NULL) {
224 pos = start;
225 return NULL;
226 }
227
228 // Assemble return results
229 SingleID* single = specsToID(specs, FORWARD);
230 if (single != NULL) {
231 single->filter = specs->filter;
232 }
233 delete specs;
234 return single;
235}
236
237/**
238 * Parse a global filter of the form "[f]" or "([f])", depending
239 * on 'withParens'.
240 * @param id the pattern the parse
241 * @param pos INPUT-OUTPUT parameter. On input, the position of
242 * the first character to parse. On output, the position after
243 * the last character parsed.
244 * @param dir the direction.
245 * @param withParens INPUT-OUTPUT parameter. On entry, if
246 * withParens is 0, then parens are disallowed. If it is 1,
247 * then parens are requires. If it is -1, then parens are
248 * optional, and the return result will be set to 0 or 1.
249 * @param canonID OUTPUT parameter. The pattern for the filter
250 * added to the canonID, either at the end, if dir is FORWARD, or
251 * at the start, if dir is REVERSE. The pattern will be enclosed
252 * in parentheses if appropriate, and will be suffixed with an
253 * ID_DELIM character. May be NULL.
254 * @return a UnicodeSet object or NULL. A non-NULL results
255 * indicates a successful parse, regardless of whether the filter
256 * applies to the given direction. The caller should discard it
257 * if withParens != (dir == REVERSE).
258 */
259UnicodeSet* TransliteratorIDParser::parseGlobalFilter(const UnicodeString& id, int32_t& pos,
260 int32_t dir,
261 int32_t& withParens,
262 UnicodeString* canonID) {
263 UnicodeSet* filter = NULL;
264 int32_t start = pos;
265
266 if (withParens == -1) {
267 withParens = ICU_Utility::parseChar(id, pos, OPEN_REV) ? 1 : 0;
268 } else if (withParens == 1) {
269 if (!ICU_Utility::parseChar(id, pos, OPEN_REV)) {
270 pos = start;
271 return NULL;
272 }
273 }
274
275 ICU_Utility::skipWhitespace(id, pos, TRUE);
276
277 if (UnicodeSet::resemblesPattern(id, pos)) {
278 ParsePosition ppos(pos);
279 UErrorCode ec = U_ZERO_ERROR;
280 filter = new UnicodeSet(id, ppos, USET_IGNORE_SPACE, NULL, ec);
281 /* test for NULL */
282 if (filter == 0) {
283 pos = start;
284 return 0;
285 }
286 if (U_FAILURE(ec)) {
287 delete filter;
288 pos = start;
289 return NULL;
290 }
291
292 UnicodeString pattern;
293 id.extractBetween(pos, ppos.getIndex(), pattern);
294 pos = ppos.getIndex();
295
296 if (withParens == 1 && !ICU_Utility::parseChar(id, pos, CLOSE_REV)) {
297 delete filter;
298 pos = start;
299 return NULL;
300 }
301
302 // In the forward direction, append the pattern to the
303 // canonID. In the reverse, insert it at zero, and invert
304 // the presence of parens ("A" <-> "(A)").
305 if (canonID != NULL) {
306 if (dir == FORWARD) {
307 if (withParens == 1) {
308 pattern.insert(0, OPEN_REV);
309 pattern.append(CLOSE_REV);
310 }
311 canonID->append(pattern).append(ID_DELIM);
312 } else {
313 if (withParens == 0) {
314 pattern.insert(0, OPEN_REV);
315 pattern.append(CLOSE_REV);
316 }
317 canonID->insert(0, pattern);
318 canonID->insert(pattern.length(), ID_DELIM);
319 }
320 }
321 }
322
323 return filter;
324}
325
326U_CDECL_BEGIN
327static void U_CALLCONV _deleteSingleID(void* obj) {
328 delete (TransliteratorIDParser::SingleID*) obj;
329}
330
331static void U_CALLCONV _deleteTransliteratorTrIDPars(void* obj) {
332 delete (Transliterator*) obj;
333}
334U_CDECL_END
335
336/**
337 * Parse a compound ID, consisting of an optional forward global
338 * filter, a separator, one or more single IDs delimited by
339 * separators, an an optional reverse global filter. The
340 * separator is a semicolon. The global filters are UnicodeSet
341 * patterns. The reverse global filter must be enclosed in
342 * parentheses.
343 * @param id the pattern the parse
344 * @param dir the direction.
345 * @param canonID OUTPUT parameter that receives the canonical ID,
346 * consisting of canonical IDs for all elements, as returned by
347 * parseSingleID(), separated by semicolons. Previous contents
348 * are discarded.
349 * @param list OUTPUT parameter that receives a list of SingleID
350 * objects representing the parsed IDs. Previous contents are
351 * discarded.
352 * @param globalFilter OUTPUT parameter that receives a pointer to
353 * a newly created global filter for this ID in this direction, or
354 * NULL if there is none.
355 * @return TRUE if the parse succeeds, that is, if the entire
356 * id is consumed without syntax error.
357 */
358UBool TransliteratorIDParser::parseCompoundID(const UnicodeString& id, int32_t dir,
359 UnicodeString& canonID,
360 UVector& list,
361 UnicodeSet*& globalFilter) {
362 UErrorCode ec = U_ZERO_ERROR;
363 int32_t i;
364 int32_t pos = 0;
365 int32_t withParens = 1;
366 list.removeAllElements();
367 UnicodeSet* filter;
368 globalFilter = NULL;
369 canonID.truncate(0);
370
371 // Parse leading global filter, if any
372 withParens = 0; // parens disallowed
373 filter = parseGlobalFilter(id, pos, dir, withParens, &canonID);
374 if (filter != NULL) {
375 if (!ICU_Utility::parseChar(id, pos, ID_DELIM)) {
376 // Not a global filter; backup and resume
377 canonID.truncate(0);
378 pos = 0;
379 }
380 if (dir == FORWARD) {
381 globalFilter = filter;
382 } else {
383 delete filter;
384 }
385 filter = NULL;
386 }
387
388 UBool sawDelimiter = TRUE;
389 for (;;) {
390 SingleID* single = parseSingleID(id, pos, dir, ec);
391 if (single == NULL) {
392 break;
393 }
394 if (dir == FORWARD) {
395 list.addElement(single, ec);
396 } else {
397 list.insertElementAt(single, 0, ec);
398 }
399 if (U_FAILURE(ec)) {
400 goto FAIL;
401 }
402 if (!ICU_Utility::parseChar(id, pos, ID_DELIM)) {
403 sawDelimiter = FALSE;
404 break;
405 }
406 }
407
408 if (list.size() == 0) {
409 goto FAIL;
410 }
411
412 // Construct canonical ID
413 for (i=0; i<list.size(); ++i) {
414 SingleID* single = (SingleID*) list.elementAt(i);
415 canonID.append(single->canonID);
416 if (i != (list.size()-1)) {
417 canonID.append(ID_DELIM);
418 }
419 }
420
421 // Parse trailing global filter, if any, and only if we saw
422 // a trailing delimiter after the IDs.
423 if (sawDelimiter) {
424 withParens = 1; // parens required
425 filter = parseGlobalFilter(id, pos, dir, withParens, &canonID);
426 if (filter != NULL) {
427 // Don't require trailing ';', but parse it if present
428 ICU_Utility::parseChar(id, pos, ID_DELIM);
429
430 if (dir == REVERSE) {
431 globalFilter = filter;
432 } else {
433 delete filter;
434 }
435 filter = NULL;
436 }
437 }
438
439 // Trailing unparsed text is a syntax error
440 ICU_Utility::skipWhitespace(id, pos, TRUE);
441 if (pos != id.length()) {
442 goto FAIL;
443 }
444
445 return TRUE;
446
447 FAIL:
448 UObjectDeleter *save = list.setDeleter(_deleteSingleID);
449 list.removeAllElements();
450 list.setDeleter(save);
451 delete globalFilter;
452 globalFilter = NULL;
453 return FALSE;
454}
455
456/**
457 * Convert the elements of the 'list' vector, which are SingleID
458 * objects, into actual Transliterator objects. In the course of
459 * this, some (or all) entries may be removed. If all entries
460 * are removed, the NULL transliterator will be added.
461 *
462 * Delete entries with empty basicIDs; these are generated by
463 * elements like "(A)" in the forward direction, or "A()" in
464 * the reverse. THIS MAY RESULT IN AN EMPTY VECTOR. Convert
465 * SingleID entries to actual transliterators.
466 *
467 * @param list vector of SingleID objects. On exit, vector
468 * of one or more Transliterators.
469 * @return new value of insertIndex. The index will shift if
470 * there are empty items, like "(Lower)", with indices less than
471 * insertIndex.
472 */
473void TransliteratorIDParser::instantiateList(UVector& list,
474 UErrorCode& ec) {
475 UVector tlist(ec);
476 if (U_FAILURE(ec)) {
477 goto RETURN;
478 }
479 tlist.setDeleter(_deleteTransliteratorTrIDPars);
480
481 Transliterator* t;
482 int32_t i;
483 for (i=0; i<=list.size(); ++i) { // [sic]: i<=list.size()
484 // We run the loop too long by one, so we can
485 // do an insert after the last element
486 if (i==list.size()) {
487 break;
488 }
489
490 SingleID* single = (SingleID*) list.elementAt(i);
491 if (single->basicID.length() != 0) {
492 t = single->createInstance();
493 if (t == NULL) {
494 ec = U_INVALID_ID;
495 goto RETURN;
496 }
497 tlist.addElement(t, ec);
498 if (U_FAILURE(ec)) {
499 delete t;
500 goto RETURN;
501 }
502 }
503 }
504
505 // An empty list is equivalent to a NULL transliterator.
506 if (tlist.size() == 0) {
507 t = createBasicInstance(UnicodeString(TRUE, ANY_NULL, 8), NULL);
508 if (t == NULL) {
509 // Should never happen
510 ec = U_INTERNAL_TRANSLITERATOR_ERROR;
511 }
512 tlist.addElement(t, ec);
513 if (U_FAILURE(ec)) {
514 delete t;
515 }
516 }
517
518 RETURN:
519
520 UObjectDeleter *save = list.setDeleter(_deleteSingleID);
521 list.removeAllElements();
522
523 if (U_SUCCESS(ec)) {
524 list.setDeleter(_deleteTransliteratorTrIDPars);
525
526 while (tlist.size() > 0) {
527 t = (Transliterator*) tlist.orphanElementAt(0);
528 list.addElement(t, ec);
529 if (U_FAILURE(ec)) {
530 delete t;
531 list.removeAllElements();
532 break;
533 }
534 }
535 }
536
537 list.setDeleter(save);
538}
539
540/**
541 * Parse an ID into pieces. Take IDs of the form T, T/V, S-T,
542 * S-T/V, or S/V-T. If the source is missing, return a source of
543 * ANY.
544 * @param id the id string, in any of several forms
545 * @return an array of 4 strings: source, target, variant, and
546 * isSourcePresent. If the source is not present, ANY will be
547 * given as the source, and isSourcePresent will be NULL. Otherwise
548 * isSourcePresent will be non-NULL. The target may be empty if the
549 * id is not well-formed. The variant may be empty.
550 */
551void TransliteratorIDParser::IDtoSTV(const UnicodeString& id,
552 UnicodeString& source,
553 UnicodeString& target,
554 UnicodeString& variant,
555 UBool& isSourcePresent) {
556 source.setTo(ANY, 3);
557 target.truncate(0);
558 variant.truncate(0);
559
560 int32_t sep = id.indexOf(TARGET_SEP);
561 int32_t var = id.indexOf(VARIANT_SEP);
562 if (var < 0) {
563 var = id.length();
564 }
565 isSourcePresent = FALSE;
566
567 if (sep < 0) {
568 // Form: T/V or T (or /V)
569 id.extractBetween(0, var, target);
570 id.extractBetween(var, id.length(), variant);
571 } else if (sep < var) {
572 // Form: S-T/V or S-T (or -T/V or -T)
573 if (sep > 0) {
574 id.extractBetween(0, sep, source);
575 isSourcePresent = TRUE;
576 }
577 id.extractBetween(++sep, var, target);
578 id.extractBetween(var, id.length(), variant);
579 } else {
580 // Form: (S/V-T or /V-T)
581 if (var > 0) {
582 id.extractBetween(0, var, source);
583 isSourcePresent = TRUE;
584 }
585 id.extractBetween(var, sep++, variant);
586 id.extractBetween(sep, id.length(), target);
587 }
588
589 if (variant.length() > 0) {
590 variant.remove(0, 1);
591 }
592}
593
594/**
595 * Given source, target, and variant strings, concatenate them into a
596 * full ID. If the source is empty, then "Any" will be used for the
597 * source, so the ID will always be of the form s-t/v or s-t.
598 */
599void TransliteratorIDParser::STVtoID(const UnicodeString& source,
600 const UnicodeString& target,
601 const UnicodeString& variant,
602 UnicodeString& id) {
603 id = source;
604 if (id.length() == 0) {
605 id.setTo(ANY, 3);
606 }
607 id.append(TARGET_SEP).append(target);
608 if (variant.length() != 0) {
609 id.append(VARIANT_SEP).append(variant);
610 }
611 // NUL-terminate the ID string for getTerminatedBuffer.
612 // This prevents valgrind and Purify warnings.
613 id.append((UChar)0);
614 id.truncate(id.length()-1);
615}
616
617/**
618 * Register two targets as being inverses of one another. For
619 * example, calling registerSpecialInverse("NFC", "NFD", TRUE) causes
620 * Transliterator to form the following inverse relationships:
621 *
622 * <pre>NFC => NFD
623 * Any-NFC => Any-NFD
624 * NFD => NFC
625 * Any-NFD => Any-NFC</pre>
626 *
627 * (Without the special inverse registration, the inverse of NFC
628 * would be NFC-Any.) Note that NFD is shorthand for Any-NFD, but
629 * that the presence or absence of "Any-" is preserved.
630 *
631 * <p>The relationship is symmetrical; registering (a, b) is
632 * equivalent to registering (b, a).
633 *
634 * <p>The relevant IDs must still be registered separately as
635 * factories or classes.
636 *
637 * <p>Only the targets are specified. Special inverses always
638 * have the form Any-Target1 <=> Any-Target2. The target should
639 * have canonical casing (the casing desired to be produced when
640 * an inverse is formed) and should contain no whitespace or other
641 * extraneous characters.
642 *
643 * @param target the target against which to register the inverse
644 * @param inverseTarget the inverse of target, that is
645 * Any-target.getInverse() => Any-inverseTarget
646 * @param bidirectional if TRUE, register the reverse relation
647 * as well, that is, Any-inverseTarget.getInverse() => Any-target
648 */
649void TransliteratorIDParser::registerSpecialInverse(const UnicodeString& target,
650 const UnicodeString& inverseTarget,
651 UBool bidirectional,
652 UErrorCode &status) {
653 umtx_initOnce(gSpecialInversesInitOnce, init, status);
654 if (U_FAILURE(status)) {
655 return;
656 }
657
658 // If target == inverseTarget then force bidirectional => FALSE
659 if (bidirectional && 0==target.caseCompare(inverseTarget, U_FOLD_CASE_DEFAULT)) {
660 bidirectional = FALSE;
661 }
662
663 Mutex lock(&LOCK);
664
665 UnicodeString *tempus = new UnicodeString(inverseTarget); // Used for null pointer check before usage.
666 if (tempus == NULL) {
667 status = U_MEMORY_ALLOCATION_ERROR;
668 return;
669 }
670 SPECIAL_INVERSES->put(target, tempus, status);
671 if (bidirectional) {
672 tempus = new UnicodeString(target);
673 if (tempus == NULL) {
674 status = U_MEMORY_ALLOCATION_ERROR;
675 return;
676 }
677 SPECIAL_INVERSES->put(inverseTarget, tempus, status);
678 }
679}
680
681//----------------------------------------------------------------
682// Private implementation
683//----------------------------------------------------------------
684
685/**
686 * Parse an ID into component pieces. Take IDs of the form T,
687 * T/V, S-T, S-T/V, or S/V-T. If the source is missing, return a
688 * source of ANY.
689 * @param id the id string, in any of several forms
690 * @param pos INPUT-OUTPUT parameter. On input, pos is the
691 * offset of the first character to parse in id. On output,
692 * pos is the offset after the last parsed character. If the
693 * parse failed, pos will be unchanged.
694 * @param allowFilter2 if TRUE, a UnicodeSet pattern is allowed
695 * at any location between specs or delimiters, and is returned
696 * as the fifth string in the array.
697 * @return a Specs object, or NULL if the parse failed. If
698 * neither source nor target was seen in the parsed id, then the
699 * parse fails. If allowFilter is TRUE, then the parsed filter
700 * pattern is returned in the Specs object, otherwise the returned
701 * filter reference is NULL. If the parse fails for any reason
702 * NULL is returned.
703 */
704TransliteratorIDParser::Specs*
705TransliteratorIDParser::parseFilterID(const UnicodeString& id, int32_t& pos,
706 UBool allowFilter) {
707 UnicodeString first;
708 UnicodeString source;
709 UnicodeString target;
710 UnicodeString variant;
711 UnicodeString filter;
712 UChar delimiter = 0;
713 int32_t specCount = 0;
714 int32_t start = pos;
715
716 // This loop parses one of the following things with each
717 // pass: a filter, a delimiter character (either '-' or '/'),
718 // or a spec (source, target, or variant).
719 for (;;) {
720 ICU_Utility::skipWhitespace(id, pos, TRUE);
721 if (pos == id.length()) {
722 break;
723 }
724
725 // Parse filters
726 if (allowFilter && filter.length() == 0 &&
727 UnicodeSet::resemblesPattern(id, pos)) {
728
729 ParsePosition ppos(pos);
730 UErrorCode ec = U_ZERO_ERROR;
731 UnicodeSet set(id, ppos, USET_IGNORE_SPACE, NULL, ec);
732 if (U_FAILURE(ec)) {
733 pos = start;
734 return NULL;
735 }
736 id.extractBetween(pos, ppos.getIndex(), filter);
737 pos = ppos.getIndex();
738 continue;
739 }
740
741 if (delimiter == 0) {
742 UChar c = id.charAt(pos);
743 if ((c == TARGET_SEP && target.length() == 0) ||
744 (c == VARIANT_SEP && variant.length() == 0)) {
745 delimiter = c;
746 ++pos;
747 continue;
748 }
749 }
750
751 // We are about to try to parse a spec with no delimiter
752 // when we can no longer do so (we can only do so at the
753 // start); break.
754 if (delimiter == 0 && specCount > 0) {
755 break;
756 }
757
758 UnicodeString spec = ICU_Utility::parseUnicodeIdentifier(id, pos);
759 if (spec.length() == 0) {
760 // Note that if there was a trailing delimiter, we
761 // consume it. So Foo-, Foo/, Foo-Bar/, and Foo/Bar-
762 // are legal.
763 break;
764 }
765
766 switch (delimiter) {
767 case 0:
768 first = spec;
769 break;
770 case TARGET_SEP:
771 target = spec;
772 break;
773 case VARIANT_SEP:
774 variant = spec;
775 break;
776 }
777 ++specCount;
778 delimiter = 0;
779 }
780
781 // A spec with no prior character is either source or target,
782 // depending on whether an explicit "-target" was seen.
783 if (first.length() != 0) {
784 if (target.length() == 0) {
785 target = first;
786 } else {
787 source = first;
788 }
789 }
790
791 // Must have either source or target
792 if (source.length() == 0 && target.length() == 0) {
793 pos = start;
794 return NULL;
795 }
796
797 // Empty source or target defaults to ANY
798 UBool sawSource = TRUE;
799 if (source.length() == 0) {
800 source.setTo(ANY, 3);
801 sawSource = FALSE;
802 }
803 if (target.length() == 0) {
804 target.setTo(ANY, 3);
805 }
806
807 return new Specs(source, target, variant, sawSource, filter);
808}
809
810/**
811 * Givens a Spec object, convert it to a SingleID object. The
812 * Spec object is a more unprocessed parse result. The SingleID
813 * object contains information about canonical and basic IDs.
814 * @return a SingleID; never returns NULL. Returned object always
815 * has 'filter' field of NULL.
816 */
817TransliteratorIDParser::SingleID*
818TransliteratorIDParser::specsToID(const Specs* specs, int32_t dir) {
819 UnicodeString canonID;
820 UnicodeString basicID;
821 UnicodeString basicPrefix;
822 if (specs != NULL) {
823 UnicodeString buf;
824 if (dir == FORWARD) {
825 if (specs->sawSource) {
826 buf.append(specs->source).append(TARGET_SEP);
827 } else {
828 basicPrefix = specs->source;
829 basicPrefix.append(TARGET_SEP);
830 }
831 buf.append(specs->target);
832 } else {
833 buf.append(specs->target).append(TARGET_SEP).append(specs->source);
834 }
835 if (specs->variant.length() != 0) {
836 buf.append(VARIANT_SEP).append(specs->variant);
837 }
838 basicID = basicPrefix;
839 basicID.append(buf);
840 if (specs->filter.length() != 0) {
841 buf.insert(0, specs->filter);
842 }
843 canonID = buf;
844 }
845 return new SingleID(canonID, basicID);
846}
847
848/**
849 * Given a Specs object, return a SingleID representing the
850 * special inverse of that ID. If there is no special inverse
851 * then return NULL.
852 * @return a SingleID or NULL. Returned object always has
853 * 'filter' field of NULL.
854 */
855TransliteratorIDParser::SingleID*
856TransliteratorIDParser::specsToSpecialInverse(const Specs& specs, UErrorCode &status) {
857 if (0!=specs.source.caseCompare(ANY, 3, U_FOLD_CASE_DEFAULT)) {
858 return NULL;
859 }
860 umtx_initOnce(gSpecialInversesInitOnce, init, status);
861 if (U_FAILURE(status)) {
862 return NULL;
863 }
864
865 UnicodeString* inverseTarget;
866
867 umtx_lock(&LOCK);
868 inverseTarget = (UnicodeString*) SPECIAL_INVERSES->get(specs.target);
869 umtx_unlock(&LOCK);
870
871 if (inverseTarget != NULL) {
872 // If the original ID contained "Any-" then make the
873 // special inverse "Any-Foo"; otherwise make it "Foo".
874 // So "Any-NFC" => "Any-NFD" but "NFC" => "NFD".
875 UnicodeString buf;
876 if (specs.filter.length() != 0) {
877 buf.append(specs.filter);
878 }
879 if (specs.sawSource) {
880 buf.append(ANY, 3).append(TARGET_SEP);
881 }
882 buf.append(*inverseTarget);
883
884 UnicodeString basicID(TRUE, ANY, 3);
885 basicID.append(TARGET_SEP).append(*inverseTarget);
886
887 if (specs.variant.length() != 0) {
888 buf.append(VARIANT_SEP).append(specs.variant);
889 basicID.append(VARIANT_SEP).append(specs.variant);
890 }
891 return new SingleID(buf, basicID);
892 }
893 return NULL;
894}
895
896/**
897 * Glue method to get around access problems in C++. This would
898 * ideally be inline but we want to avoid a circular header
899 * dependency.
900 */
901Transliterator* TransliteratorIDParser::createBasicInstance(const UnicodeString& id, const UnicodeString* canonID) {
902 return Transliterator::createBasicInstance(id, canonID);
903}
904
905/**
906 * Initialize static memory. Called through umtx_initOnce only.
907 */
908void U_CALLCONV TransliteratorIDParser::init(UErrorCode &status) {
909 U_ASSERT(SPECIAL_INVERSES == NULL);
910 ucln_i18n_registerCleanup(UCLN_I18N_TRANSLITERATOR, utrans_transliterator_cleanup);
911
912 SPECIAL_INVERSES = new Hashtable(TRUE, status);
913 if (SPECIAL_INVERSES == NULL) {
914 status = U_MEMORY_ALLOCATION_ERROR;
915 return;
916 }
917 SPECIAL_INVERSES->setValueDeleter(uprv_deleteUObject);
918}
919
920/**
921 * Free static memory.
922 */
923void TransliteratorIDParser::cleanup() {
924 if (SPECIAL_INVERSES) {
925 delete SPECIAL_INVERSES;
926 SPECIAL_INVERSES = NULL;
927 }
928 gSpecialInversesInitOnce.reset();
929}
930
931U_NAMESPACE_END
932
933#endif /* #if !UCONFIG_NO_TRANSLITERATION */
934
935//eof
936