1 // Copyright (C) 2016 and later: Unicode, Inc. and others.
2 // License & terms of use: http://www.unicode.org/copyright.html
3 /*
4 *******************************************************************************
5 *
6 *   Copyright (C) 1999-2014, International Business Machines
7 *   Corporation and others.  All Rights Reserved.
8 *
9 *******************************************************************************
10 *   file name:  uniset_props.cpp
11 *   encoding:   US-ASCII
12 *   tab size:   8 (not used)
13 *   indentation:4
14 *
15 *   created on: 2004aug25
16 *   created by: Markus W. Scherer
17 *
18 *   Character property dependent functions moved here from uniset.cpp
19 */
20 
21 #include "unicode/utypes.h"
22 #include "unicode/uniset.h"
23 #include "unicode/parsepos.h"
24 #include "unicode/uchar.h"
25 #include "unicode/uscript.h"
26 #include "unicode/symtable.h"
27 #include "unicode/uset.h"
28 #include "unicode/locid.h"
29 #include "unicode/brkiter.h"
30 #include "uset_imp.h"
31 #include "ruleiter.h"
32 #include "cmemory.h"
33 #include "ucln_cmn.h"
34 #include "util.h"
35 #include "uvector.h"
36 #include "uprops.h"
37 #include "propname.h"
38 #include "normalizer2impl.h"
39 #include "ucase.h"
40 #include "ubidi_props.h"
41 #include "uinvchar.h"
42 #include "uprops.h"
43 #include "charstr.h"
44 #include "cstring.h"
45 #include "mutex.h"
46 #include "umutex.h"
47 #include "uassert.h"
48 #include "hash.h"
49 
50 U_NAMESPACE_USE
51 
52 // initial storage. Must be >= 0
53 // *** same as in uniset.cpp ! ***
54 #define START_EXTRA 16
55 
56 // Define UChar constants using hex for EBCDIC compatibility
57 // Used #define to reduce private static exports and memory access time.
58 #define SET_OPEN        ((UChar)0x005B) /*[*/
59 #define SET_CLOSE       ((UChar)0x005D) /*]*/
60 #define HYPHEN          ((UChar)0x002D) /*-*/
61 #define COMPLEMENT      ((UChar)0x005E) /*^*/
62 #define COLON           ((UChar)0x003A) /*:*/
63 #define BACKSLASH       ((UChar)0x005C) /*\*/
64 #define INTERSECTION    ((UChar)0x0026) /*&*/
65 #define UPPER_U         ((UChar)0x0055) /*U*/
66 #define LOWER_U         ((UChar)0x0075) /*u*/
67 #define OPEN_BRACE      ((UChar)123)    /*{*/
68 #define CLOSE_BRACE     ((UChar)125)    /*}*/
69 #define UPPER_P         ((UChar)0x0050) /*P*/
70 #define LOWER_P         ((UChar)0x0070) /*p*/
71 #define UPPER_N         ((UChar)78)     /*N*/
72 #define EQUALS          ((UChar)0x003D) /*=*/
73 
74 //static const UChar POSIX_OPEN[]  = { SET_OPEN,COLON,0 };  // "[:"
75 static const UChar POSIX_CLOSE[] = { COLON,SET_CLOSE,0 };  // ":]"
76 //static const UChar PERL_OPEN[]   = { BACKSLASH,LOWER_P,0 }; // "\\p"
77 //static const UChar PERL_CLOSE[]  = { CLOSE_BRACE,0 };    // "}"
78 //static const UChar NAME_OPEN[]   = { BACKSLASH,UPPER_N,0 };  // "\\N"
79 static const UChar HYPHEN_RIGHT_BRACE[] = {HYPHEN,SET_CLOSE,0}; /*-]*/
80 
81 // Special property set IDs
82 static const char ANY[]   = "ANY";   // [\u0000-\U0010FFFF]
83 static const char ASCII[] = "ASCII"; // [\u0000-\u007F]
84 static const char ASSIGNED[] = "Assigned"; // [:^Cn:]
85 
86 // Unicode name property alias
87 #define NAME_PROP "na"
88 #define NAME_PROP_LENGTH 2
89 
90 /**
91  * Delimiter string used in patterns to close a category reference:
92  * ":]".  Example: "[:Lu:]".
93  */
94 //static const UChar CATEGORY_CLOSE[] = {COLON, SET_CLOSE, 0x0000}; /* ":]" */
95 
96 // Cached sets ------------------------------------------------------------- ***
97 
98 U_CDECL_BEGIN
99 static UBool U_CALLCONV uset_cleanup();
100 
101 struct Inclusion {
102     UnicodeSet  *fSet;
103     UInitOnce    fInitOnce;
104 };
105 static Inclusion gInclusions[UPROPS_SRC_COUNT]; // cached getInclusions()
106 
107 static UnicodeSet *uni32Singleton;
108 static icu::UInitOnce uni32InitOnce = U_INITONCE_INITIALIZER;
109 
110 //----------------------------------------------------------------
111 // Inclusions list
112 //----------------------------------------------------------------
113 
114 // USetAdder implementation
115 // Does not use uset.h to reduce code dependencies
116 static void U_CALLCONV
117 _set_add(USet *set, UChar32 c) {
118     ((UnicodeSet *)set)->add(c);
119 }
120 
121 static void U_CALLCONV
122 _set_addRange(USet *set, UChar32 start, UChar32 end) {
123     ((UnicodeSet *)set)->add(start, end);
124 }
125 
126 static void U_CALLCONV
127 _set_addString(USet *set, const UChar *str, int32_t length) {
128     ((UnicodeSet *)set)->add(UnicodeString((UBool)(length<0), str, length));
129 }
130 
131 /**
132  * Cleanup function for UnicodeSet
133  */
134 static UBool U_CALLCONV uset_cleanup(void) {
135     for(int32_t i = UPROPS_SRC_NONE; i < UPROPS_SRC_COUNT; ++i) {
136         Inclusion &in = gInclusions[i];
137         delete in.fSet;
138         in.fSet = NULL;
139         in.fInitOnce.reset();
140     }
141 
142     delete uni32Singleton;
143     uni32Singleton = NULL;
144     uni32InitOnce.reset();
145     return TRUE;
146 }
147 
148 U_CDECL_END
149 
150 U_NAMESPACE_BEGIN
151 
152 /*
153 Reduce excessive reallocation, and make it easier to detect initialization problems.
154 Usually you don't see smaller sets than this for Unicode 5.0.
155 */
156 #define DEFAULT_INCLUSION_CAPACITY 3072
157 
158 void U_CALLCONV UnicodeSet_initInclusion(int32_t src, UErrorCode &status) {
159     // This function is invoked only via umtx_initOnce().
160     // This function is a friend of class UnicodeSet.
161 
162     U_ASSERT(src >=0 && src<UPROPS_SRC_COUNT);
163     UnicodeSet * &incl = gInclusions[src].fSet;
164     U_ASSERT(incl == NULL);
165 
166     incl = new UnicodeSet();
167     if (incl == NULL) {
168         status = U_MEMORY_ALLOCATION_ERROR;
169         return;
170     }
171     USetAdder sa = {
172         (USet *)incl,
173         _set_add,
174         _set_addRange,
175         _set_addString,
176         NULL, // don't need remove()
177         NULL // don't need removeRange()
178     };
179 
180     incl->ensureCapacity(DEFAULT_INCLUSION_CAPACITY, status);
181     switch(src) {
182     case UPROPS_SRC_CHAR:
183         uchar_addPropertyStarts(&sa, &status);
184         break;
185     case UPROPS_SRC_PROPSVEC:
186         upropsvec_addPropertyStarts(&sa, &status);
187         break;
188     case UPROPS_SRC_CHAR_AND_PROPSVEC:
189         uchar_addPropertyStarts(&sa, &status);
190         upropsvec_addPropertyStarts(&sa, &status);
191         break;
192 #if !UCONFIG_NO_NORMALIZATION
193     case UPROPS_SRC_CASE_AND_NORM: {
194         const Normalizer2Impl *impl=Normalizer2Factory::getNFCImpl(status);
195         if(U_SUCCESS(status)) {
196             impl->addPropertyStarts(&sa, status);
197         }
198         ucase_addPropertyStarts(ucase_getSingleton(), &sa, &status);
199         break;
200     }
201     case UPROPS_SRC_NFC: {
202         const Normalizer2Impl *impl=Normalizer2Factory::getNFCImpl(status);
203         if(U_SUCCESS(status)) {
204             impl->addPropertyStarts(&sa, status);
205         }
206         break;
207     }
208     case UPROPS_SRC_NFKC: {
209         const Normalizer2Impl *impl=Normalizer2Factory::getNFKCImpl(status);
210         if(U_SUCCESS(status)) {
211             impl->addPropertyStarts(&sa, status);
212         }
213         break;
214     }
215     case UPROPS_SRC_NFKC_CF: {
216         const Normalizer2Impl *impl=Normalizer2Factory::getNFKC_CFImpl(status);
217         if(U_SUCCESS(status)) {
218             impl->addPropertyStarts(&sa, status);
219         }
220         break;
221     }
222     case UPROPS_SRC_NFC_CANON_ITER: {
223         const Normalizer2Impl *impl=Normalizer2Factory::getNFCImpl(status);
224         if(U_SUCCESS(status)) {
225             impl->addCanonIterPropertyStarts(&sa, status);
226         }
227         break;
228     }
229 #endif
230     case UPROPS_SRC_CASE:
231         ucase_addPropertyStarts(ucase_getSingleton(), &sa, &status);
232         break;
233     case UPROPS_SRC_BIDI:
234         ubidi_addPropertyStarts(ubidi_getSingleton(), &sa, &status);
235         break;
236     default:
237         status = U_INTERNAL_PROGRAM_ERROR;
238         break;
239     }
240 
241     if (U_FAILURE(status)) {
242         delete incl;
243         incl = NULL;
244         return;
245     }
246     // Compact for caching
247     incl->compact();
248     ucln_common_registerCleanup(UCLN_COMMON_USET, uset_cleanup);
249 }
250 
251 
252 
253 const UnicodeSet* UnicodeSet::getInclusions(int32_t src, UErrorCode &status) {
254     U_ASSERT(src >=0 && src<UPROPS_SRC_COUNT);
255     Inclusion &i = gInclusions[src];
256     umtx_initOnce(i.fInitOnce, &UnicodeSet_initInclusion, src, status);
257     return i.fSet;
258 }
259 
260 
261 // Cache some sets for other services -------------------------------------- ***
262 void U_CALLCONV createUni32Set(UErrorCode &errorCode) {
263     U_ASSERT(uni32Singleton == NULL);
264     uni32Singleton = new UnicodeSet(UNICODE_STRING_SIMPLE("[:age=3.2:]"), errorCode);
265     if(uni32Singleton==NULL) {
266         errorCode=U_MEMORY_ALLOCATION_ERROR;
267     } else {
268         uni32Singleton->freeze();
269     }
270     ucln_common_registerCleanup(UCLN_COMMON_USET, uset_cleanup);
271 }
272 
273 
274 U_CFUNC UnicodeSet *
275 uniset_getUnicode32Instance(UErrorCode &errorCode) {
276     umtx_initOnce(uni32InitOnce, &createUni32Set, errorCode);
277     return uni32Singleton;
278 }
279 
280 // helper functions for matching of pattern syntax pieces ------------------ ***
281 // these functions are parallel to the PERL_OPEN etc. strings above
282 
283 // using these functions is not only faster than UnicodeString::compare() and
284 // caseCompare(), but they also make UnicodeSet work for simple patterns when
285 // no Unicode properties data is available - when caseCompare() fails
286 
287 static inline UBool
288 isPerlOpen(const UnicodeString &pattern, int32_t pos) {
289     UChar c;
290     return pattern.charAt(pos)==BACKSLASH && ((c=pattern.charAt(pos+1))==LOWER_P || c==UPPER_P);
291 }
292 
293 /*static inline UBool
294 isPerlClose(const UnicodeString &pattern, int32_t pos) {
295     return pattern.charAt(pos)==CLOSE_BRACE;
296 }*/
297 
298 static inline UBool
299 isNameOpen(const UnicodeString &pattern, int32_t pos) {
300     return pattern.charAt(pos)==BACKSLASH && pattern.charAt(pos+1)==UPPER_N;
301 }
302 
303 static inline UBool
304 isPOSIXOpen(const UnicodeString &pattern, int32_t pos) {
305     return pattern.charAt(pos)==SET_OPEN && pattern.charAt(pos+1)==COLON;
306 }
307 
308 /*static inline UBool
309 isPOSIXClose(const UnicodeString &pattern, int32_t pos) {
310     return pattern.charAt(pos)==COLON && pattern.charAt(pos+1)==SET_CLOSE;
311 }*/
312 
313 // TODO memory debugging provided inside uniset.cpp
314 // could be made available here but probably obsolete with use of modern
315 // memory leak checker tools
316 #define _dbgct(me)
317 
318 //----------------------------------------------------------------
319 // Constructors &c
320 //----------------------------------------------------------------
321 
322 /**
323  * Constructs a set from the given pattern, optionally ignoring
324  * white space.  See the class description for the syntax of the
325  * pattern language.
326  * @param pattern a string specifying what characters are in the set
327  */
328 UnicodeSet::UnicodeSet(const UnicodeString& pattern,
329                        UErrorCode& status) :
330     len(0), capacity(START_EXTRA), list(0), bmpSet(0), buffer(0),
331     bufferCapacity(0), patLen(0), pat(NULL), strings(NULL), stringSpan(NULL),
332     fFlags(0)
333 {
334     if(U_SUCCESS(status)){
335         list = (UChar32*) uprv_malloc(sizeof(UChar32) * capacity);
336         /* test for NULL */
337         if(list == NULL) {
338             status = U_MEMORY_ALLOCATION_ERROR;
339         }else{
340             allocateStrings(status);
341             applyPattern(pattern, status);
342         }
343     }
344     _dbgct(this);
345 }
346 
347 //----------------------------------------------------------------
348 // Public API
349 //----------------------------------------------------------------
350 
351 UnicodeSet& UnicodeSet::applyPattern(const UnicodeString& pattern,
352                                      UErrorCode& status) {
353     // Equivalent to
354     //   return applyPattern(pattern, USET_IGNORE_SPACE, NULL, status);
355     // but without dependency on closeOver().
356     ParsePosition pos(0);
357     applyPatternIgnoreSpace(pattern, pos, NULL, status);
358     if (U_FAILURE(status)) return *this;
359 
360     int32_t i = pos.getIndex();
361     // Skip over trailing whitespace
362     ICU_Utility::skipWhitespace(pattern, i, TRUE);
363     if (i != pattern.length()) {
364         status = U_ILLEGAL_ARGUMENT_ERROR;
365     }
366     return *this;
367 }
368 
369 void
370 UnicodeSet::applyPatternIgnoreSpace(const UnicodeString& pattern,
371                                     ParsePosition& pos,
372                                     const SymbolTable* symbols,
373                                     UErrorCode& status) {
374     if (U_FAILURE(status)) {
375         return;
376     }
377     if (isFrozen()) {
378         status = U_NO_WRITE_PERMISSION;
379         return;
380     }
381     // Need to build the pattern in a temporary string because
382     // _applyPattern calls add() etc., which set pat to empty.
383     UnicodeString rebuiltPat;
384     RuleCharacterIterator chars(pattern, symbols, pos);
385     applyPattern(chars, symbols, rebuiltPat, USET_IGNORE_SPACE, NULL, status);
386     if (U_FAILURE(status)) return;
387     if (chars.inVariable()) {
388         // syntaxError(chars, "Extra chars in variable value");
389         status = U_MALFORMED_SET;
390         return;
391     }
392     setPattern(rebuiltPat);
393 }
394 
395 /**
396  * Return true if the given position, in the given pattern, appears
397  * to be the start of a UnicodeSet pattern.
398  */
399 UBool UnicodeSet::resemblesPattern(const UnicodeString& pattern, int32_t pos) {
400     return ((pos+1) < pattern.length() &&
401             pattern.charAt(pos) == (UChar)91/*[*/) ||
402         resemblesPropertyPattern(pattern, pos);
403 }
404 
405 //----------------------------------------------------------------
406 // Implementation: Pattern parsing
407 //----------------------------------------------------------------
408 
409 /**
410  * A small all-inline class to manage a UnicodeSet pointer.  Add
411  * operator->() etc. as needed.
412  */
413 class UnicodeSetPointer {
414     UnicodeSet* p;
415 public:
416     inline UnicodeSetPointer() : p(0) {}
417     inline ~UnicodeSetPointer() { delete p; }
418     inline UnicodeSet* pointer() { return p; }
419     inline UBool allocate() {
420         if (p == 0) {
421             p = new UnicodeSet();
422         }
423         return p != 0;
424     }
425 };
426 
427 /**
428  * Parse the pattern from the given RuleCharacterIterator.  The
429  * iterator is advanced over the parsed pattern.
430  * @param chars iterator over the pattern characters.  Upon return
431  * it will be advanced to the first character after the parsed
432  * pattern, or the end of the iteration if all characters are
433  * parsed.
434  * @param symbols symbol table to use to parse and dereference
435  * variables, or null if none.
436  * @param rebuiltPat the pattern that was parsed, rebuilt or
437  * copied from the input pattern, as appropriate.
438  * @param options a bit mask of zero or more of the following:
439  * IGNORE_SPACE, CASE.
440  */
441 void UnicodeSet::applyPattern(RuleCharacterIterator& chars,
442                               const SymbolTable* symbols,
443                               UnicodeString& rebuiltPat,
444                               uint32_t options,
445                               UnicodeSet& (UnicodeSet::*caseClosure)(int32_t attribute),
446                               UErrorCode& ec) {
447     if (U_FAILURE(ec)) return;
448 
449     // Syntax characters: [ ] ^ - & { }
450 
451     // Recognized special forms for chars, sets: c-c s-s s&s
452 
453     int32_t opts = RuleCharacterIterator::PARSE_VARIABLES |
454                    RuleCharacterIterator::PARSE_ESCAPES;
455     if ((options & USET_IGNORE_SPACE) != 0) {
456         opts |= RuleCharacterIterator::SKIP_WHITESPACE;
457     }
458 
459     UnicodeString patLocal, buf;
460     UBool usePat = FALSE;
461     UnicodeSetPointer scratch;
462     RuleCharacterIterator::Pos backup;
463 
464     // mode: 0=before [, 1=between [...], 2=after ]
465     // lastItem: 0=none, 1=char, 2=set
466     int8_t lastItem = 0, mode = 0;
467     UChar32 lastChar = 0;
468     UChar op = 0;
469 
470     UBool invert = FALSE;
471 
472     clear();
473 
474     while (mode != 2 && !chars.atEnd()) {
475         U_ASSERT((lastItem == 0 && op == 0) ||
476                  (lastItem == 1 && (op == 0 || op == HYPHEN /*'-'*/)) ||
477                  (lastItem == 2 && (op == 0 || op == HYPHEN /*'-'*/ ||
478                                     op == INTERSECTION /*'&'*/)));
479 
480         UChar32 c = 0;
481         UBool literal = FALSE;
482         UnicodeSet* nested = 0; // alias - do not delete
483 
484         // -------- Check for property pattern
485 
486         // setMode: 0=none, 1=unicodeset, 2=propertypat, 3=preparsed
487         int8_t setMode = 0;
488         if (resemblesPropertyPattern(chars, opts)) {
489             setMode = 2;
490         }
491 
492         // -------- Parse '[' of opening delimiter OR nested set.
493         // If there is a nested set, use `setMode' to define how
494         // the set should be parsed.  If the '[' is part of the
495         // opening delimiter for this pattern, parse special
496         // strings "[", "[^", "[-", and "[^-".  Check for stand-in
497         // characters representing a nested set in the symbol
498         // table.
499 
500         else {
501             // Prepare to backup if necessary
502             chars.getPos(backup);
503             c = chars.next(opts, literal, ec);
504             if (U_FAILURE(ec)) return;
505 
506             if (c == 0x5B /*'['*/ && !literal) {
507                 if (mode == 1) {
508                     chars.setPos(backup); // backup
509                     setMode = 1;
510                 } else {
511                     // Handle opening '[' delimiter
512                     mode = 1;
513                     patLocal.append((UChar) 0x5B /*'['*/);
514                     chars.getPos(backup); // prepare to backup
515                     c = chars.next(opts, literal, ec);
516                     if (U_FAILURE(ec)) return;
517                     if (c == 0x5E /*'^'*/ && !literal) {
518                         invert = TRUE;
519                         patLocal.append((UChar) 0x5E /*'^'*/);
520                         chars.getPos(backup); // prepare to backup
521                         c = chars.next(opts, literal, ec);
522                         if (U_FAILURE(ec)) return;
523                     }
524                     // Fall through to handle special leading '-';
525                     // otherwise restart loop for nested [], \p{}, etc.
526                     if (c == HYPHEN /*'-'*/) {
527                         literal = TRUE;
528                         // Fall through to handle literal '-' below
529                     } else {
530                         chars.setPos(backup); // backup
531                         continue;
532                     }
533                 }
534             } else if (symbols != 0) {
535                 const UnicodeFunctor *m = symbols->lookupMatcher(c);
536                 if (m != 0) {
537                     const UnicodeSet *ms = dynamic_cast<const UnicodeSet *>(m);
538                     if (ms == NULL) {
539                         ec = U_MALFORMED_SET;
540                         return;
541                     }
542                     // casting away const, but `nested' won't be modified
543                     // (important not to modify stored set)
544                     nested = const_cast<UnicodeSet*>(ms);
545                     setMode = 3;
546                 }
547             }
548         }
549 
550         // -------- Handle a nested set.  This either is inline in
551         // the pattern or represented by a stand-in that has
552         // previously been parsed and was looked up in the symbol
553         // table.
554 
555         if (setMode != 0) {
556             if (lastItem == 1) {
557                 if (op != 0) {
558                     // syntaxError(chars, "Char expected after operator");
559                     ec = U_MALFORMED_SET;
560                     return;
561                 }
562                 add(lastChar, lastChar);
563                 _appendToPat(patLocal, lastChar, FALSE);
564                 lastItem = 0;
565                 op = 0;
566             }
567 
568             if (op == HYPHEN /*'-'*/ || op == INTERSECTION /*'&'*/) {
569                 patLocal.append(op);
570             }
571 
572             if (nested == 0) {
573                 // lazy allocation
574                 if (!scratch.allocate()) {
575                     ec = U_MEMORY_ALLOCATION_ERROR;
576                     return;
577                 }
578                 nested = scratch.pointer();
579             }
580             switch (setMode) {
581             case 1:
582                 nested->applyPattern(chars, symbols, patLocal, options, caseClosure, ec);
583                 break;
584             case 2:
585                 chars.skipIgnored(opts);
586                 nested->applyPropertyPattern(chars, patLocal, ec);
587                 if (U_FAILURE(ec)) return;
588                 break;
589             case 3: // `nested' already parsed
590                 nested->_toPattern(patLocal, FALSE);
591                 break;
592             }
593 
594             usePat = TRUE;
595 
596             if (mode == 0) {
597                 // Entire pattern is a category; leave parse loop
598                 *this = *nested;
599                 mode = 2;
600                 break;
601             }
602 
603             switch (op) {
604             case HYPHEN: /*'-'*/
605                 removeAll(*nested);
606                 break;
607             case INTERSECTION: /*'&'*/
608                 retainAll(*nested);
609                 break;
610             case 0:
611                 addAll(*nested);
612                 break;
613             }
614 
615             op = 0;
616             lastItem = 2;
617 
618             continue;
619         }
620 
621         if (mode == 0) {
622             // syntaxError(chars, "Missing '['");
623             ec = U_MALFORMED_SET;
624             return;
625         }
626 
627         // -------- Parse special (syntax) characters.  If the
628         // current character is not special, or if it is escaped,
629         // then fall through and handle it below.
630 
631         if (!literal) {
632             switch (c) {
633             case 0x5D /*']'*/:
634                 if (lastItem == 1) {
635                     add(lastChar, lastChar);
636                     _appendToPat(patLocal, lastChar, FALSE);
637                 }
638                 // Treat final trailing '-' as a literal
639                 if (op == HYPHEN /*'-'*/) {
640                     add(op, op);
641                     patLocal.append(op);
642                 } else if (op == INTERSECTION /*'&'*/) {
643                     // syntaxError(chars, "Trailing '&'");
644                     ec = U_MALFORMED_SET;
645                     return;
646                 }
647                 patLocal.append((UChar) 0x5D /*']'*/);
648                 mode = 2;
649                 continue;
650             case HYPHEN /*'-'*/:
651                 if (op == 0) {
652                     if (lastItem != 0) {
653                         op = (UChar) c;
654                         continue;
655                     } else {
656                         // Treat final trailing '-' as a literal
657                         add(c, c);
658                         c = chars.next(opts, literal, ec);
659                         if (U_FAILURE(ec)) return;
660                         if (c == 0x5D /*']'*/ && !literal) {
661                             patLocal.append(HYPHEN_RIGHT_BRACE, 2);
662                             mode = 2;
663                             continue;
664                         }
665                     }
666                 }
667                 // syntaxError(chars, "'-' not after char or set");
668                 ec = U_MALFORMED_SET;
669                 return;
670             case INTERSECTION /*'&'*/:
671                 if (lastItem == 2 && op == 0) {
672                     op = (UChar) c;
673                     continue;
674                 }
675                 // syntaxError(chars, "'&' not after set");
676                 ec = U_MALFORMED_SET;
677                 return;
678             case 0x5E /*'^'*/:
679                 // syntaxError(chars, "'^' not after '['");
680                 ec = U_MALFORMED_SET;
681                 return;
682             case 0x7B /*'{'*/:
683                 if (op != 0) {
684                     // syntaxError(chars, "Missing operand after operator");
685                     ec = U_MALFORMED_SET;
686                     return;
687                 }
688                 if (lastItem == 1) {
689                     add(lastChar, lastChar);
690                     _appendToPat(patLocal, lastChar, FALSE);
691                 }
692                 lastItem = 0;
693                 buf.truncate(0);
694                 {
695                     UBool ok = FALSE;
696                     while (!chars.atEnd()) {
697                         c = chars.next(opts, literal, ec);
698                         if (U_FAILURE(ec)) return;
699                         if (c == 0x7D /*'}'*/ && !literal) {
700                             ok = TRUE;
701                             break;
702                         }
703                         buf.append(c);
704                     }
705                     if (buf.length() < 1 || !ok) {
706                         // syntaxError(chars, "Invalid multicharacter string");
707                         ec = U_MALFORMED_SET;
708                         return;
709                     }
710                 }
711                 // We have new string. Add it to set and continue;
712                 // we don't need to drop through to the further
713                 // processing
714                 add(buf);
715                 patLocal.append((UChar) 0x7B /*'{'*/);
716                 _appendToPat(patLocal, buf, FALSE);
717                 patLocal.append((UChar) 0x7D /*'}'*/);
718                 continue;
719             case SymbolTable::SYMBOL_REF:
720                 //         symbols  nosymbols
721                 // [a-$]   error    error (ambiguous)
722                 // [a$]    anchor   anchor
723                 // [a-$x]  var "x"* literal '$'
724                 // [a-$.]  error    literal '$'
725                 // *We won't get here in the case of var "x"
726                 {
727                     chars.getPos(backup);
728                     c = chars.next(opts, literal, ec);
729                     if (U_FAILURE(ec)) return;
730                     UBool anchor = (c == 0x5D /*']'*/ && !literal);
731                     if (symbols == 0 && !anchor) {
732                         c = SymbolTable::SYMBOL_REF;
733                         chars.setPos(backup);
734                         break; // literal '$'
735                     }
736                     if (anchor && op == 0) {
737                         if (lastItem == 1) {
738                             add(lastChar, lastChar);
739                             _appendToPat(patLocal, lastChar, FALSE);
740                         }
741                         add(U_ETHER);
742                         usePat = TRUE;
743                         patLocal.append((UChar) SymbolTable::SYMBOL_REF);
744                         patLocal.append((UChar) 0x5D /*']'*/);
745                         mode = 2;
746                         continue;
747                     }
748                     // syntaxError(chars, "Unquoted '$'");
749                     ec = U_MALFORMED_SET;
750                     return;
751                 }
752             default:
753                 break;
754             }
755         }
756 
757         // -------- Parse literal characters.  This includes both
758         // escaped chars ("\u4E01") and non-syntax characters
759         // ("a").
760 
761         switch (lastItem) {
762         case 0:
763             lastItem = 1;
764             lastChar = c;
765             break;
766         case 1:
767             if (op == HYPHEN /*'-'*/) {
768                 if (lastChar >= c) {
769                     // Don't allow redundant (a-a) or empty (b-a) ranges;
770                     // these are most likely typos.
771                     // syntaxError(chars, "Invalid range");
772                     ec = U_MALFORMED_SET;
773                     return;
774                 }
775                 add(lastChar, c);
776                 _appendToPat(patLocal, lastChar, FALSE);
777                 patLocal.append(op);
778                 _appendToPat(patLocal, c, FALSE);
779                 lastItem = 0;
780                 op = 0;
781             } else {
782                 add(lastChar, lastChar);
783                 _appendToPat(patLocal, lastChar, FALSE);
784                 lastChar = c;
785             }
786             break;
787         case 2:
788             if (op != 0) {
789                 // syntaxError(chars, "Set expected after operator");
790                 ec = U_MALFORMED_SET;
791                 return;
792             }
793             lastChar = c;
794             lastItem = 1;
795             break;
796         }
797     }
798 
799     if (mode != 2) {
800         // syntaxError(chars, "Missing ']'");
801         ec = U_MALFORMED_SET;
802         return;
803     }
804 
805     chars.skipIgnored(opts);
806 
807     /**
808      * Handle global flags (invert, case insensitivity).  If this
809      * pattern should be compiled case-insensitive, then we need
810      * to close over case BEFORE COMPLEMENTING.  This makes
811      * patterns like /[^abc]/i work.
812      */
813     if ((options & USET_CASE_INSENSITIVE) != 0) {
814         (this->*caseClosure)(USET_CASE_INSENSITIVE);
815     }
816     else if ((options & USET_ADD_CASE_MAPPINGS) != 0) {
817         (this->*caseClosure)(USET_ADD_CASE_MAPPINGS);
818     }
819     if (invert) {
820         complement();
821     }
822 
823     // Use the rebuilt pattern (patLocal) only if necessary.  Prefer the
824     // generated pattern.
825     if (usePat) {
826         rebuiltPat.append(patLocal);
827     } else {
828         _generatePattern(rebuiltPat, FALSE);
829     }
830     if (isBogus() && U_SUCCESS(ec)) {
831         // We likely ran out of memory. AHHH!
832         ec = U_MEMORY_ALLOCATION_ERROR;
833     }
834 }
835 
836 //----------------------------------------------------------------
837 // Property set implementation
838 //----------------------------------------------------------------
839 
840 static UBool numericValueFilter(UChar32 ch, void* context) {
841     return u_getNumericValue(ch) == *(double*)context;
842 }
843 
844 static UBool generalCategoryMaskFilter(UChar32 ch, void* context) {
845     int32_t value = *(int32_t*)context;
846     return (U_GET_GC_MASK((UChar32) ch) & value) != 0;
847 }
848 
849 static UBool versionFilter(UChar32 ch, void* context) {
850     static const UVersionInfo none = { 0, 0, 0, 0 };
851     UVersionInfo v;
852     u_charAge(ch, v);
853     UVersionInfo* version = (UVersionInfo*)context;
854     return uprv_memcmp(&v, &none, sizeof(v)) > 0 && uprv_memcmp(&v, version, sizeof(v)) <= 0;
855 }
856 
857 typedef struct {
858     UProperty prop;
859     int32_t value;
860 } IntPropertyContext;
861 
862 static UBool intPropertyFilter(UChar32 ch, void* context) {
863     IntPropertyContext* c = (IntPropertyContext*)context;
864     return u_getIntPropertyValue((UChar32) ch, c->prop) == c->value;
865 }
866 
867 static UBool scriptExtensionsFilter(UChar32 ch, void* context) {
868     return uscript_hasScript(ch, *(UScriptCode*)context);
869 }
870 
871 /**
872  * Generic filter-based scanning code for UCD property UnicodeSets.
873  */
874 void UnicodeSet::applyFilter(UnicodeSet::Filter filter,
875                              void* context,
876                              int32_t src,
877                              UErrorCode &status) {
878     if (U_FAILURE(status)) return;
879 
880     // Logically, walk through all Unicode characters, noting the start
881     // and end of each range for which filter.contain(c) is
882     // true.  Add each range to a set.
883     //
884     // To improve performance, use an inclusions set which
885     // encodes information about character ranges that are known
886     // to have identical properties.
887     // getInclusions(src) contains exactly the first characters of
888     // same-value ranges for the given properties "source".
889     const UnicodeSet* inclusions = getInclusions(src, status);
890     if (U_FAILURE(status)) {
891         return;
892     }
893 
894     clear();
895 
896     UChar32 startHasProperty = -1;
897     int32_t limitRange = inclusions->getRangeCount();
898 
899     for (int j=0; j<limitRange; ++j) {
900         // get current range
901         UChar32 start = inclusions->getRangeStart(j);
902         UChar32 end = inclusions->getRangeEnd(j);
903 
904         // for all the code points in the range, process
905         for (UChar32 ch = start; ch <= end; ++ch) {
906             // only add to this UnicodeSet on inflection points --
907             // where the hasProperty value changes to false
908             if ((*filter)(ch, context)) {
909                 if (startHasProperty < 0) {
910                     startHasProperty = ch;
911                 }
912             } else if (startHasProperty >= 0) {
913                 add(startHasProperty, ch-1);
914                 startHasProperty = -1;
915             }
916         }
917     }
918     if (startHasProperty >= 0) {
919         add((UChar32)startHasProperty, (UChar32)0x10FFFF);
920     }
921     if (isBogus() && U_SUCCESS(status)) {
922         // We likely ran out of memory. AHHH!
923         status = U_MEMORY_ALLOCATION_ERROR;
924     }
925 }
926 
927 static UBool mungeCharName(char* dst, const char* src, int32_t dstCapacity) {
928     /* Note: we use ' ' in compiler code page */
929     int32_t j = 0;
930     char ch;
931     --dstCapacity; /* make room for term. zero */
932     while ((ch = *src++) != 0) {
933         if (ch == ' ' && (j==0 || (j>0 && dst[j-1]==' '))) {
934             continue;
935         }
936         if (j >= dstCapacity) return FALSE;
937         dst[j++] = ch;
938     }
939     if (j > 0 && dst[j-1] == ' ') --j;
940     dst[j] = 0;
941     return TRUE;
942 }
943 
944 //----------------------------------------------------------------
945 // Property set API
946 //----------------------------------------------------------------
947 
948 #define FAIL(ec) {ec=U_ILLEGAL_ARGUMENT_ERROR; return *this;}
949 
950 UnicodeSet&
951 UnicodeSet::applyIntPropertyValue(UProperty prop, int32_t value, UErrorCode& ec) {
952     if (U_FAILURE(ec) || isFrozen()) return *this;
953 
954     if (prop == UCHAR_GENERAL_CATEGORY_MASK) {
955         applyFilter(generalCategoryMaskFilter, &value, UPROPS_SRC_CHAR, ec);
956     } else if (prop == UCHAR_SCRIPT_EXTENSIONS) {
957         UScriptCode script = (UScriptCode)value;
958         applyFilter(scriptExtensionsFilter, &script, UPROPS_SRC_PROPSVEC, ec);
959     } else {
960         IntPropertyContext c = {prop, value};
961         applyFilter(intPropertyFilter, &c, uprops_getSource(prop), ec);
962     }
963     return *this;
964 }
965 
966 UnicodeSet&
967 UnicodeSet::applyPropertyAlias(const UnicodeString& prop,
968                                const UnicodeString& value,
969                                UErrorCode& ec) {
970     if (U_FAILURE(ec) || isFrozen()) return *this;
971 
972     // prop and value used to be converted to char * using the default
973     // converter instead of the invariant conversion.
974     // This should not be necessary because all Unicode property and value
975     // names use only invariant characters.
976     // If there are any variant characters, then we won't find them anyway.
977     // Checking first avoids assertion failures in the conversion.
978     if( !uprv_isInvariantUString(prop.getBuffer(), prop.length()) ||
979         !uprv_isInvariantUString(value.getBuffer(), value.length())
980     ) {
981         FAIL(ec);
982     }
983     CharString pname, vname;
984     pname.appendInvariantChars(prop, ec);
985     vname.appendInvariantChars(value, ec);
986     if (U_FAILURE(ec)) return *this;
987 
988     UProperty p;
989     int32_t v;
990     UBool mustNotBeEmpty = FALSE, invert = FALSE;
991 
992     if (value.length() > 0) {
993         p = u_getPropertyEnum(pname.data());
994         if (p == UCHAR_INVALID_CODE) FAIL(ec);
995 
996         // Treat gc as gcm
997         if (p == UCHAR_GENERAL_CATEGORY) {
998             p = UCHAR_GENERAL_CATEGORY_MASK;
999         }
1000 
1001         if ((p >= UCHAR_BINARY_START && p < UCHAR_BINARY_LIMIT) ||
1002             (p >= UCHAR_INT_START && p < UCHAR_INT_LIMIT) ||
1003             (p >= UCHAR_MASK_START && p < UCHAR_MASK_LIMIT)) {
1004             v = u_getPropertyValueEnum(p, vname.data());
1005             if (v == UCHAR_INVALID_CODE) {
1006                 // Handle numeric CCC
1007                 if (p == UCHAR_CANONICAL_COMBINING_CLASS ||
1008                     p == UCHAR_TRAIL_CANONICAL_COMBINING_CLASS ||
1009                     p == UCHAR_LEAD_CANONICAL_COMBINING_CLASS) {
1010                     char* end;
1011                     double value = uprv_strtod(vname.data(), &end);
1012                     v = (int32_t) value;
1013                     if (v != value || v < 0 || *end != 0) {
1014                         // non-integral or negative value, or trailing junk
1015                         FAIL(ec);
1016                     }
1017                     // If the resultant set is empty then the numeric value
1018                     // was invalid.
1019                     mustNotBeEmpty = TRUE;
1020                 } else {
1021                     FAIL(ec);
1022                 }
1023             }
1024         }
1025 
1026         else {
1027 
1028             switch (p) {
1029             case UCHAR_NUMERIC_VALUE:
1030                 {
1031                     char* end;
1032                     double value = uprv_strtod(vname.data(), &end);
1033                     if (*end != 0) {
1034                         FAIL(ec);
1035                     }
1036                     applyFilter(numericValueFilter, &value, UPROPS_SRC_CHAR, ec);
1037                     return *this;
1038                 }
1039             case UCHAR_NAME:
1040                 {
1041                     // Must munge name, since u_charFromName() does not do
1042                     // 'loose' matching.
1043                     char buf[128]; // it suffices that this be > uprv_getMaxCharNameLength
1044                     if (!mungeCharName(buf, vname.data(), sizeof(buf))) FAIL(ec);
1045                     UChar32 ch = u_charFromName(U_EXTENDED_CHAR_NAME, buf, &ec);
1046                     if (U_SUCCESS(ec)) {
1047                         clear();
1048                         add(ch);
1049                         return *this;
1050                     } else {
1051                         FAIL(ec);
1052                     }
1053                 }
1054             case UCHAR_UNICODE_1_NAME:
1055                 // ICU 49 deprecates the Unicode_1_Name property APIs.
1056                 FAIL(ec);
1057             case UCHAR_AGE:
1058                 {
1059                     // Must munge name, since u_versionFromString() does not do
1060                     // 'loose' matching.
1061                     char buf[128];
1062                     if (!mungeCharName(buf, vname.data(), sizeof(buf))) FAIL(ec);
1063                     UVersionInfo version;
1064                     u_versionFromString(version, buf);
1065                     applyFilter(versionFilter, &version, UPROPS_SRC_PROPSVEC, ec);
1066                     return *this;
1067                 }
1068             case UCHAR_SCRIPT_EXTENSIONS:
1069                 v = u_getPropertyValueEnum(UCHAR_SCRIPT, vname.data());
1070                 if (v == UCHAR_INVALID_CODE) {
1071                     FAIL(ec);
1072                 }
1073                 // fall through to calling applyIntPropertyValue()
1074                 break;
1075             default:
1076                 // p is a non-binary, non-enumerated property that we
1077                 // don't support (yet).
1078                 FAIL(ec);
1079             }
1080         }
1081     }
1082 
1083     else {
1084         // value is empty.  Interpret as General Category, Script, or
1085         // Binary property.
1086         p = UCHAR_GENERAL_CATEGORY_MASK;
1087         v = u_getPropertyValueEnum(p, pname.data());
1088         if (v == UCHAR_INVALID_CODE) {
1089             p = UCHAR_SCRIPT;
1090             v = u_getPropertyValueEnum(p, pname.data());
1091             if (v == UCHAR_INVALID_CODE) {
1092                 p = u_getPropertyEnum(pname.data());
1093                 if (p >= UCHAR_BINARY_START && p < UCHAR_BINARY_LIMIT) {
1094                     v = 1;
1095                 } else if (0 == uprv_comparePropertyNames(ANY, pname.data())) {
1096                     set(MIN_VALUE, MAX_VALUE);
1097                     return *this;
1098                 } else if (0 == uprv_comparePropertyNames(ASCII, pname.data())) {
1099                     set(0, 0x7F);
1100                     return *this;
1101                 } else if (0 == uprv_comparePropertyNames(ASSIGNED, pname.data())) {
1102                     // [:Assigned:]=[:^Cn:]
1103                     p = UCHAR_GENERAL_CATEGORY_MASK;
1104                     v = U_GC_CN_MASK;
1105                     invert = TRUE;
1106                 } else {
1107                     FAIL(ec);
1108                 }
1109             }
1110         }
1111     }
1112 
1113     applyIntPropertyValue(p, v, ec);
1114     if(invert) {
1115         complement();
1116     }
1117 
1118     if (U_SUCCESS(ec) && (mustNotBeEmpty && isEmpty())) {
1119         // mustNotBeEmpty is set to true if an empty set indicates
1120         // invalid input.
1121         ec = U_ILLEGAL_ARGUMENT_ERROR;
1122     }
1123 
1124     if (isBogus() && U_SUCCESS(ec)) {
1125         // We likely ran out of memory. AHHH!
1126         ec = U_MEMORY_ALLOCATION_ERROR;
1127     }
1128     return *this;
1129 }
1130 
1131 //----------------------------------------------------------------
1132 // Property set patterns
1133 //----------------------------------------------------------------
1134 
1135 /**
1136  * Return true if the given position, in the given pattern, appears
1137  * to be the start of a property set pattern.
1138  */
1139 UBool UnicodeSet::resemblesPropertyPattern(const UnicodeString& pattern,
1140                                            int32_t pos) {
1141     // Patterns are at least 5 characters long
1142     if ((pos+5) > pattern.length()) {
1143         return FALSE;
1144     }
1145 
1146     // Look for an opening [:, [:^, \p, or \P
1147     return isPOSIXOpen(pattern, pos) || isPerlOpen(pattern, pos) || isNameOpen(pattern, pos);
1148 }
1149 
1150 /**
1151  * Return true if the given iterator appears to point at a
1152  * property pattern.  Regardless of the result, return with the
1153  * iterator unchanged.
1154  * @param chars iterator over the pattern characters.  Upon return
1155  * it will be unchanged.
1156  * @param iterOpts RuleCharacterIterator options
1157  */
1158 UBool UnicodeSet::resemblesPropertyPattern(RuleCharacterIterator& chars,
1159                                            int32_t iterOpts) {
1160     // NOTE: literal will always be FALSE, because we don't parse escapes.
1161     UBool result = FALSE, literal;
1162     UErrorCode ec = U_ZERO_ERROR;
1163     iterOpts &= ~RuleCharacterIterator::PARSE_ESCAPES;
1164     RuleCharacterIterator::Pos pos;
1165     chars.getPos(pos);
1166     UChar32 c = chars.next(iterOpts, literal, ec);
1167     if (c == 0x5B /*'['*/ || c == 0x5C /*'\\'*/) {
1168         UChar32 d = chars.next(iterOpts & ~RuleCharacterIterator::SKIP_WHITESPACE,
1169                                literal, ec);
1170         result = (c == 0x5B /*'['*/) ? (d == 0x3A /*':'*/) :
1171                  (d == 0x4E /*'N'*/ || d == 0x70 /*'p'*/ || d == 0x50 /*'P'*/);
1172     }
1173     chars.setPos(pos);
1174     return result && U_SUCCESS(ec);
1175 }
1176 
1177 /**
1178  * Parse the given property pattern at the given parse position.
1179  */
1180 UnicodeSet& UnicodeSet::applyPropertyPattern(const UnicodeString& pattern,
1181                                              ParsePosition& ppos,
1182                                              UErrorCode &ec) {
1183     int32_t pos = ppos.getIndex();
1184 
1185     UBool posix = FALSE; // true for [:pat:], false for \p{pat} \P{pat} \N{pat}
1186     UBool isName = FALSE; // true for \N{pat}, o/w false
1187     UBool invert = FALSE;
1188 
1189     if (U_FAILURE(ec)) return *this;
1190 
1191     // Minimum length is 5 characters, e.g. \p{L}
1192     if ((pos+5) > pattern.length()) {
1193         FAIL(ec);
1194     }
1195 
1196     // On entry, ppos should point to one of the following locations:
1197     // Look for an opening [:, [:^, \p, or \P
1198     if (isPOSIXOpen(pattern, pos)) {
1199         posix = TRUE;
1200         pos += 2;
1201         pos = ICU_Utility::skipWhitespace(pattern, pos);
1202         if (pos < pattern.length() && pattern.charAt(pos) == COMPLEMENT) {
1203             ++pos;
1204             invert = TRUE;
1205         }
1206     } else if (isPerlOpen(pattern, pos) || isNameOpen(pattern, pos)) {
1207         UChar c = pattern.charAt(pos+1);
1208         invert = (c == UPPER_P);
1209         isName = (c == UPPER_N);
1210         pos += 2;
1211         pos = ICU_Utility::skipWhitespace(pattern, pos);
1212         if (pos == pattern.length() || pattern.charAt(pos++) != OPEN_BRACE) {
1213             // Syntax error; "\p" or "\P" not followed by "{"
1214             FAIL(ec);
1215         }
1216     } else {
1217         // Open delimiter not seen
1218         FAIL(ec);
1219     }
1220 
1221     // Look for the matching close delimiter, either :] or }
1222     int32_t close;
1223     if (posix) {
1224       close = pattern.indexOf(POSIX_CLOSE, 2, pos);
1225     } else {
1226       close = pattern.indexOf(CLOSE_BRACE, pos);
1227     }
1228     if (close < 0) {
1229         // Syntax error; close delimiter missing
1230         FAIL(ec);
1231     }
1232 
1233     // Look for an '=' sign.  If this is present, we will parse a
1234     // medium \p{gc=Cf} or long \p{GeneralCategory=Format}
1235     // pattern.
1236     int32_t equals = pattern.indexOf(EQUALS, pos);
1237     UnicodeString propName, valueName;
1238     if (equals >= 0 && equals < close && !isName) {
1239         // Equals seen; parse medium/long pattern
1240         pattern.extractBetween(pos, equals, propName);
1241         pattern.extractBetween(equals+1, close, valueName);
1242     }
1243 
1244     else {
1245         // Handle case where no '=' is seen, and \N{}
1246         pattern.extractBetween(pos, close, propName);
1247 
1248         // Handle \N{name}
1249         if (isName) {
1250             // This is a little inefficient since it means we have to
1251             // parse NAME_PROP back to UCHAR_NAME even though we already
1252             // know it's UCHAR_NAME.  If we refactor the API to
1253             // support args of (UProperty, char*) then we can remove
1254             // NAME_PROP and make this a little more efficient.
1255             valueName = propName;
1256             propName = UnicodeString(NAME_PROP, NAME_PROP_LENGTH, US_INV);
1257         }
1258     }
1259 
1260     applyPropertyAlias(propName, valueName, ec);
1261 
1262     if (U_SUCCESS(ec)) {
1263         if (invert) {
1264             complement();
1265         }
1266 
1267         // Move to the limit position after the close delimiter if the
1268         // parse succeeded.
1269         ppos.setIndex(close + (posix ? 2 : 1));
1270     }
1271 
1272     return *this;
1273 }
1274 
1275 /**
1276  * Parse a property pattern.
1277  * @param chars iterator over the pattern characters.  Upon return
1278  * it will be advanced to the first character after the parsed
1279  * pattern, or the end of the iteration if all characters are
1280  * parsed.
1281  * @param rebuiltPat the pattern that was parsed, rebuilt or
1282  * copied from the input pattern, as appropriate.
1283  */
1284 void UnicodeSet::applyPropertyPattern(RuleCharacterIterator& chars,
1285                                       UnicodeString& rebuiltPat,
1286                                       UErrorCode& ec) {
1287     if (U_FAILURE(ec)) return;
1288     UnicodeString pattern;
1289     chars.lookahead(pattern);
1290     ParsePosition pos(0);
1291     applyPropertyPattern(pattern, pos, ec);
1292     if (U_FAILURE(ec)) return;
1293     if (pos.getIndex() == 0) {
1294         // syntaxError(chars, "Invalid property pattern");
1295         ec = U_MALFORMED_SET;
1296         return;
1297     }
1298     chars.jumpahead(pos.getIndex());
1299     rebuiltPat.append(pattern, 0, pos.getIndex());
1300 }
1301 
1302 U_NAMESPACE_END
1303