1 // © 2016 and later: Unicode, Inc. and others.
2 // License & terms of use: http://www.unicode.org/copyright.html
3 //
4 //  regexst.h
5 //
6 //  Copyright (C) 2004-2015, International Business Machines Corporation and others.
7 //  All Rights Reserved.
8 //
9 //  This file contains class RegexStaticSets
10 //
11 //  This class is internal to the regular expression implementation.
12 //  For the public Regular Expression API, see the file "unicode/regex.h"
13 //
14 //  RegexStaticSets groups together the common UnicodeSets that are needed
15 //   for compiling or executing RegularExpressions.  This grouping simplifies
16 //   the thread safe lazy creation and sharing of these sets across
17 //   all instances of regular expressions.
18 //
19 #include "unicode/utypes.h"
20 
21 #if !UCONFIG_NO_REGULAR_EXPRESSIONS
22 
23 #include "unicode/unistr.h"
24 #include "unicode/uniset.h"
25 #include "unicode/uchar.h"
26 #include "unicode/regex.h"
27 #include "uprops.h"
28 #include "cmemory.h"
29 #include "cstring.h"
30 #include "uassert.h"
31 #include "ucln_in.h"
32 #include "umutex.h"
33 
34 #include "regexcst.h"   // Contains state table for the regex pattern parser.
35                         //   generated by a Perl script.
36 #include "regexst.h"
37 
38 
39 
40 U_NAMESPACE_BEGIN
41 
42 
43 //------------------------------------------------------------------------------
44 //
45 // Unicode Set pattern strings for all of the required constant sets.
46 //               Initialized with hex values for portability to EBCDIC based machines.
47 //                Really ugly, but there's no good way to avoid it.
48 //
49 //------------------------------------------------------------------------------
50 
51 // "Rule Char" Characters are those with no special meaning, and therefore do not
52 //    need to be escaped to appear as literals in a regexp.  Expressed
53 //    as the inverse of those needing escaping --  [^\*\?\+\[\(\)\{\}\^\$\|\\\.]
54 static const UChar gRuleSet_rule_char_pattern[]       = {
55  //   [    ^      \     *     \     ?     \     +     \     [     \     (     /     )
56     0x5b, 0x5e, 0x5c, 0x2a, 0x5c, 0x3f, 0x5c, 0x2b, 0x5c, 0x5b, 0x5c, 0x28, 0x5c, 0x29,
57  //   \     {    \     }     \     ^     \     $     \     |     \     \     \     .     ]
58     0x5c, 0x7b,0x5c, 0x7d, 0x5c, 0x5e, 0x5c, 0x24, 0x5c, 0x7c, 0x5c, 0x5c, 0x5c, 0x2e, 0x5d, 0};
59 
60 //
61 //   Here are the backslash escape characters that ICU's unescape() function
62 //    will handle.
63 //
64 static const UChar gUnescapeCharPattern[] = {
65 //    [     a     c     e     f     n     r     t     u     U     x    ]
66     0x5b, 0x61, 0x63, 0x65, 0x66, 0x6e, 0x72, 0x74, 0x75, 0x55, 0x78, 0x5d, 0};
67 
68 
69 //
70 //  Unicode Set Definitions for Regular Expression  \w
71 //
72 static const UChar gIsWordPattern[] = {
73 //    [     \     p     {    A     l     p     h     a     b     e     t     i      c    }
74     0x5b, 0x5c, 0x70, 0x7b, 0x61, 0x6c, 0x70, 0x68, 0x61, 0x62, 0x65, 0x74, 0x69, 0x63, 0x7d,
75 //          \     p     {    M     }                               Mark
76           0x5c, 0x70, 0x7b, 0x4d, 0x7d,
77 //          \     p     {    N     d     }                         Digit_Numeric
78           0x5c, 0x70, 0x7b, 0x4e, 0x64, 0x7d,
79 //          \     p     {    P     c     }                         Connector_Punctuation
80           0x5c, 0x70, 0x7b, 0x50, 0x63, 0x7d,
81 //          \     u     2    0     0     c      \     u     2    0     0     d     ]
82           0x5c, 0x75, 0x32, 0x30, 0x30, 0x63, 0x5c, 0x75, 0x32, 0x30, 0x30, 0x64, 0x5d, 0};
83 
84 
85 //
86 //  Unicode Set Definitions for Regular Expression  \s
87 //
88 static const UChar gIsSpacePattern[] = {
89 //        [     \     p     {     W     h     i     t     e     S     p     a     c     e     }     ]
90         0x5b, 0x5c, 0x70, 0x7b, 0x57, 0x68, 0x69, 0x74, 0x65, 0x53, 0x70, 0x61, 0x63, 0x65, 0x7d, 0x5d, 0};
91 
92 
93 //
94 //  UnicodeSets used in implementation of Grapheme Cluster detection, \X
95 //
96 static const UChar gGC_ControlPattern[] = {
97 //    [     [     :     Z     l     :     ]     [     :     Z     p     :     ]
98     0x5b, 0x5b, 0x3a, 0x5A, 0x6c, 0x3a, 0x5d, 0x5b, 0x3a, 0x5A, 0x70, 0x3a, 0x5d,
99 //    [     :     C     c     :     ]     [     :     C     f     :     ]     -
100     0x5b, 0x3a, 0x43, 0x63, 0x3a, 0x5d, 0x5b, 0x3a, 0x43, 0x66, 0x3a, 0x5d, 0x2d,
101 //    [     :     G     r     a     p     h     e     m     e     _
102     0x5b, 0x3a, 0x47, 0x72, 0x61, 0x70, 0x68, 0x65, 0x6d, 0x65, 0x5f,
103 //    E     x     t     e     n     d     :     ]     ]
104     0x45, 0x78, 0x74, 0x65, 0x6e, 0x64, 0x3a, 0x5d, 0x5d, 0};
105 
106 static const UChar gGC_ExtendPattern[] = {
107 //    [     \     p     {     G     r     a     p     h     e     m     e     _
108     0x5b, 0x5c, 0x70, 0x7b, 0x47, 0x72, 0x61, 0x70, 0x68, 0x65, 0x6d, 0x65, 0x5f,
109 //    E     x     t     e     n     d     }     ]
110     0x45, 0x78, 0x74, 0x65, 0x6e, 0x64, 0x7d, 0x5d, 0};
111 
112 static const UChar gGC_LPattern[] = {
113 //    [     \     p     {     H     a     n     g     u     l     _     S     y     l
114     0x5b, 0x5c, 0x70, 0x7b, 0x48, 0x61, 0x6e, 0x67, 0x75, 0x6c, 0x5f, 0x53, 0x79, 0x6c,
115 //    l     a     b     l     e     _     T     y     p     e     =     L     }     ]
116     0x6c, 0x61, 0x62, 0x6c, 0x65, 0x5f, 0x54, 0x79, 0x70, 0x65, 0x3d, 0x4c, 0x7d,  0x5d, 0};
117 
118 static const UChar gGC_VPattern[] = {
119 //    [     \     p     {     H     a     n     g     u     l     _     S     y     l
120     0x5b, 0x5c, 0x70, 0x7b, 0x48, 0x61, 0x6e, 0x67, 0x75, 0x6c, 0x5f, 0x53, 0x79, 0x6c,
121 //    l     a     b     l     e     _     T     y     p     e     =     V     }     ]
122     0x6c, 0x61, 0x62, 0x6c, 0x65, 0x5f, 0x54, 0x79, 0x70, 0x65, 0x3d, 0x56, 0x7d,  0x5d, 0};
123 
124 static const UChar gGC_TPattern[] = {
125 //    [     \     p     {     H     a     n     g     u     l     _     S     y     l
126     0x5b, 0x5c, 0x70, 0x7b, 0x48, 0x61, 0x6e, 0x67, 0x75, 0x6c, 0x5f, 0x53, 0x79, 0x6c,
127 //    l     a     b     l     e     _     T     y     p     e     =     T     }    ]
128     0x6c, 0x61, 0x62, 0x6c, 0x65, 0x5f, 0x54, 0x79, 0x70, 0x65, 0x3d, 0x54, 0x7d, 0x5d, 0};
129 
130 static const UChar gGC_LVPattern[] = {
131 //    [     \     p     {     H     a     n     g     u     l     _     S     y     l
132     0x5b, 0x5c, 0x70, 0x7b, 0x48, 0x61, 0x6e, 0x67, 0x75, 0x6c, 0x5f, 0x53, 0x79, 0x6c,
133 //    l     a     b     l     e     _     T     y     p     e     =     L     V     }     ]
134     0x6c, 0x61, 0x62, 0x6c, 0x65, 0x5f, 0x54, 0x79, 0x70, 0x65, 0x3d, 0x4c, 0x56, 0x7d, 0x5d, 0};
135 
136 static const UChar gGC_LVTPattern[] = {
137 //    [     \     p     {     H     a     n     g     u     l     _     S     y     l
138     0x5b, 0x5c, 0x70, 0x7b, 0x48, 0x61, 0x6e, 0x67, 0x75, 0x6c, 0x5f, 0x53, 0x79, 0x6c,
139 //    l     a     b     l     e     _     T     y     p     e     =     L     V     T     }     ]
140     0x6c, 0x61, 0x62, 0x6c, 0x65, 0x5f, 0x54, 0x79, 0x70, 0x65, 0x3d, 0x4c, 0x56, 0x54, 0x7d, 0x5d, 0};
141 
142 
143 RegexStaticSets *RegexStaticSets::gStaticSets = NULL;
144 UInitOnce gStaticSetsInitOnce = U_INITONCE_INITIALIZER;
145 
146 RegexStaticSets::RegexStaticSets(UErrorCode *status)
147 :
148 fUnescapeCharSet(UnicodeString(TRUE, gUnescapeCharPattern, -1), *status),
149 fRuleDigitsAlias(NULL),
150 fEmptyText(NULL)
151 {
152     // First zero out everything
153     int i;
154     for (i=0; i<URX_LAST_SET; i++) {
155         fPropSets[i] = NULL;
156     }
157     // Then init the sets to their correct values.
158     fPropSets[URX_ISWORD_SET]  = new UnicodeSet(UnicodeString(TRUE, gIsWordPattern, -1),     *status);
159     fPropSets[URX_ISSPACE_SET] = new UnicodeSet(UnicodeString(TRUE, gIsSpacePattern, -1),    *status);
160     fPropSets[URX_GC_EXTEND]   = new UnicodeSet(UnicodeString(TRUE, gGC_ExtendPattern, -1),  *status);
161     fPropSets[URX_GC_CONTROL]  = new UnicodeSet(UnicodeString(TRUE, gGC_ControlPattern, -1), *status);
162     fPropSets[URX_GC_L]        = new UnicodeSet(UnicodeString(TRUE, gGC_LPattern, -1),       *status);
163     fPropSets[URX_GC_V]        = new UnicodeSet(UnicodeString(TRUE, gGC_VPattern, -1),       *status);
164     fPropSets[URX_GC_T]        = new UnicodeSet(UnicodeString(TRUE, gGC_TPattern, -1),       *status);
165     fPropSets[URX_GC_LV]       = new UnicodeSet(UnicodeString(TRUE, gGC_LVPattern, -1),      *status);
166     fPropSets[URX_GC_LVT]      = new UnicodeSet(UnicodeString(TRUE, gGC_LVTPattern, -1),     *status);
167 
168     // Check for null pointers
169     if (fPropSets[URX_ISWORD_SET] == NULL || fPropSets[URX_ISSPACE_SET] == NULL || fPropSets[URX_GC_EXTEND] == NULL ||
170         fPropSets[URX_GC_CONTROL] == NULL || fPropSets[URX_GC_L] == NULL || fPropSets[URX_GC_V] == NULL ||
171         fPropSets[URX_GC_T] == NULL || fPropSets[URX_GC_LV] == NULL || fPropSets[URX_GC_LVT] == NULL) {
172         goto ExitConstrDeleteAll;
173     }
174     if (U_FAILURE(*status)) {
175         // Bail out if we were unable to create the above sets.
176         // The rest of the initialization needs them, so we cannot proceed.
177         return;
178     }
179 
180 
181     //
182     // The following sets  are dynamically constructed, because their
183     //   initialization strings would be unreasonable.
184     //
185 
186 
187     //
188     //  "Normal" is the set of characters that don't need special handling
189     //            when finding grapheme cluster boundaries.
190     //
191     fPropSets[URX_GC_NORMAL] = new UnicodeSet(0, UnicodeSet::MAX_VALUE);
192     // Null pointer check
193     if (fPropSets[URX_GC_NORMAL] == NULL) {
194     	goto ExitConstrDeleteAll;
195     }
196     fPropSets[URX_GC_NORMAL]->remove(0xac00, 0xd7a4);
197     fPropSets[URX_GC_NORMAL]->removeAll(*fPropSets[URX_GC_CONTROL]);
198     fPropSets[URX_GC_NORMAL]->removeAll(*fPropSets[URX_GC_L]);
199     fPropSets[URX_GC_NORMAL]->removeAll(*fPropSets[URX_GC_V]);
200     fPropSets[URX_GC_NORMAL]->removeAll(*fPropSets[URX_GC_T]);
201 
202     // Initialize the 8-bit fast bit sets from the parallel full
203     //   UnicodeSets.
204     for (i=0; i<URX_LAST_SET; i++) {
205         if (fPropSets[i]) {
206             fPropSets[i]->compact();
207             fPropSets8[i].init(fPropSets[i]);
208         }
209     }
210 
211     // Sets used while parsing rules, but not referenced from the parse state table
212     fRuleSets[kRuleSet_rule_char-128]   = UnicodeSet(UnicodeString(TRUE, gRuleSet_rule_char_pattern, -1),   *status);
213     fRuleSets[kRuleSet_digit_char-128].add((UChar)0x30, (UChar)0x39);    // [0-9]
214     fRuleSets[kRuleSet_ascii_letter-128].add((UChar)0x41, (UChar)0x5A);  // [A-Z]
215     fRuleSets[kRuleSet_ascii_letter-128].add((UChar)0x61, (UChar)0x7A);  // [a-z]
216     fRuleDigitsAlias = &fRuleSets[kRuleSet_digit_char-128];
217     for (i=0; i<UPRV_LENGTHOF(fRuleSets); i++) {
218         fRuleSets[i].compact();
219     }
220 
221     // Finally, initialize an empty string for utility purposes
222     fEmptyText = utext_openUChars(NULL, NULL, 0, status);
223 
224     if (U_SUCCESS(*status)) {
225         return;
226     }
227 
228 ExitConstrDeleteAll: // Remove fPropSets and fRuleSets and return error
229     for (i=0; i<URX_LAST_SET; i++) {
230         delete fPropSets[i];
231         fPropSets[i] = NULL;
232     }
233     if (U_SUCCESS(*status)) {
234         *status = U_MEMORY_ALLOCATION_ERROR;
235     }
236 }
237 
238 
239 RegexStaticSets::~RegexStaticSets() {
240     int32_t i;
241 
242     for (i=0; i<URX_LAST_SET; i++) {
243         delete fPropSets[i];
244         fPropSets[i] = NULL;
245     }
246     fRuleDigitsAlias = NULL;
247 
248     utext_close(fEmptyText);
249 }
250 
251 
252 //------------------------------------------------------------------------------
253 //
254 //   regex_cleanup      Memory cleanup function, free/delete all
255 //                      cached memory.  Called by ICU's u_cleanup() function.
256 //
257 //------------------------------------------------------------------------------
258 UBool
259 RegexStaticSets::cleanup(void) {
260     delete RegexStaticSets::gStaticSets;
261     RegexStaticSets::gStaticSets = NULL;
262     gStaticSetsInitOnce.reset();
263     return TRUE;
264 }
265 
266 U_CDECL_BEGIN
267 static UBool U_CALLCONV
268 regex_cleanup(void) {
269     return RegexStaticSets::cleanup();
270 }
271 
272 static void U_CALLCONV initStaticSets(UErrorCode &status) {
273     U_ASSERT(RegexStaticSets::gStaticSets == NULL);
274     ucln_i18n_registerCleanup(UCLN_I18N_REGEX, regex_cleanup);
275     RegexStaticSets::gStaticSets = new RegexStaticSets(&status);
276     if (U_FAILURE(status)) {
277         delete RegexStaticSets::gStaticSets;
278         RegexStaticSets::gStaticSets = NULL;
279     }
280     if (RegexStaticSets::gStaticSets == NULL && U_SUCCESS(status)) {
281         status = U_MEMORY_ALLOCATION_ERROR;
282     }
283 }
284 U_CDECL_END
285 
286 void RegexStaticSets::initGlobals(UErrorCode *status) {
287     umtx_initOnce(gStaticSetsInitOnce, &initStaticSets, *status);
288 }
289 
290 U_NAMESPACE_END
291 #endif  // !UCONFIG_NO_REGULAR_EXPRESSIONS
292