regeximp.h revision 64339d36f8bd4db5025fe2988eda22b491a9219c
1// Copyright (C) 2016 and later: Unicode, Inc. and others.
2// License & terms of use: http://www.unicode.org/copyright.html
3//
4//   Copyright (C) 2002-2015 International Business Machines Corporation
5//   and others. All rights reserved.
6//
7//   file:  regeximp.h
8//
9//           ICU Regular Expressions,
10//               Definitions of constant values used in the compiled form of
11//               a regular expression pattern.
12//
13
14#ifndef _REGEXIMP_H
15#define _REGEXIMP_H
16
17#include "unicode/utypes.h"
18#include "unicode/uobject.h"
19#include "unicode/uniset.h"
20#include "unicode/utext.h"
21
22#include "cmemory.h"
23#include "ucase.h"
24
25U_NAMESPACE_BEGIN
26
27// For debugging, define REGEX_DEBUG
28// To define with configure,
29//   CPPFLAGS="-DREGEX_DEBUG" ./runConfigureICU --enable-debug --disable-release Linux
30
31#ifdef REGEX_DEBUG
32//
33//  debugging options.  Enable one or more of the three #defines immediately following
34//
35
36//#define REGEX_SCAN_DEBUG
37#define REGEX_DUMP_DEBUG
38#define REGEX_RUN_DEBUG
39
40//  End of #defines inteded to be directly set.
41
42#include <stdio.h>
43#endif
44
45#ifdef REGEX_SCAN_DEBUG
46#define REGEX_SCAN_DEBUG_PRINTF(a) printf a
47#else
48#define REGEX_SCAN_DEBUG_PRINTF(a)
49#endif
50
51
52//
53//  Opcode types     In the compiled form of the regexp, these are the type, or opcodes,
54//                   of the entries.
55//
56enum {
57     URX_RESERVED_OP   = 0,    // For multi-operand ops, most non-first words.
58     URX_RESERVED_OP_N = 255,  // For multi-operand ops, negative operand values.
59     URX_BACKTRACK     = 1,    // Force a backtrack, as if a match test had failed.
60     URX_END           = 2,
61     URX_ONECHAR       = 3,    // Value field is the 21 bit unicode char to match
62     URX_STRING        = 4,    // Value field is index of string start
63     URX_STRING_LEN    = 5,    // Value field is string length (code units)
64     URX_STATE_SAVE    = 6,    // Value field is pattern position to push
65     URX_NOP           = 7,
66     URX_START_CAPTURE = 8,    // Value field is capture group number.
67     URX_END_CAPTURE   = 9,    // Value field is capture group number
68     URX_STATIC_SETREF = 10,   // Value field is index of set in array of sets.
69     URX_SETREF        = 11,   // Value field is index of set in array of sets.
70     URX_DOTANY        = 12,
71     URX_JMP           = 13,   // Value field is destination position in
72                                                    //   the pattern.
73     URX_FAIL          = 14,   // Stop match operation,  No match.
74
75     URX_JMP_SAV       = 15,   // Operand:  JMP destination location
76     URX_BACKSLASH_B   = 16,   // Value field:  0:  \b    1:  \B
77     URX_BACKSLASH_G   = 17,
78     URX_JMP_SAV_X     = 18,   // Conditional JMP_SAV,
79                               //    Used in (x)+, breaks loop on zero length match.
80                               //    Operand:  Jmp destination.
81     URX_BACKSLASH_X   = 19,
82     URX_BACKSLASH_Z   = 20,   // \z   Unconditional end of line.
83
84     URX_DOTANY_ALL    = 21,   // ., in the . matches any mode.
85     URX_BACKSLASH_D   = 22,   // Value field:  0:  \d    1:  \D
86     URX_CARET         = 23,   // Value field:  1:  multi-line mode.
87     URX_DOLLAR        = 24,  // Also for \Z
88
89     URX_CTR_INIT      = 25,   // Counter Inits for {Interval} loops.
90     URX_CTR_INIT_NG   = 26,   //   2 kinds, normal and non-greedy.
91                               //   These are 4 word opcodes.  See description.
92                               //    First Operand:  Data loc of counter variable
93                               //    2nd   Operand:  Pat loc of the URX_CTR_LOOPx
94                               //                    at the end of the loop.
95                               //    3rd   Operand:  Minimum count.
96                               //    4th   Operand:  Max count, -1 for unbounded.
97
98     URX_DOTANY_UNIX   = 27,   // '.' operator in UNIX_LINES mode, only \n marks end of line.
99
100     URX_CTR_LOOP      = 28,   // Loop Ops for {interval} loops.
101     URX_CTR_LOOP_NG   = 29,   //   Also in three flavors.
102                               //   Operand is loc of corresponding CTR_INIT.
103
104     URX_CARET_M_UNIX  = 30,   // '^' operator, test for start of line in multi-line
105                               //      plus UNIX_LINES mode.
106
107     URX_RELOC_OPRND   = 31,   // Operand value in multi-operand ops that refers
108                               //   back into compiled pattern code, and thus must
109                               //   be relocated when inserting/deleting ops in code.
110
111     URX_STO_SP        = 32,   // Store the stack ptr.  Operand is location within
112                               //   matcher data (not stack data) to store it.
113     URX_LD_SP         = 33,   // Load the stack pointer.  Operand is location
114                               //   to load from.
115     URX_BACKREF       = 34,   // Back Reference.  Parameter is the index of the
116                               //   capture group variables in the state stack frame.
117     URX_STO_INP_LOC   = 35,   // Store the input location.  Operand is location
118                               //   within the matcher stack frame.
119     URX_JMPX          = 36,  // Conditional JMP.
120                               //   First Operand:  JMP target location.
121                               //   Second Operand:  Data location containing an
122                               //     input position.  If current input position ==
123                               //     saved input position, FAIL rather than taking
124                               //     the JMP
125     URX_LA_START      = 37,   // Starting a LookAround expression.
126                               //   Save InputPos and SP in static data.
127                               //   Operand:  Static data offset for the save
128     URX_LA_END        = 38,   // Ending a Lookaround expression.
129                               //   Restore InputPos and Stack to saved values.
130                               //   Operand:  Static data offset for saved data.
131     URX_ONECHAR_I     = 39,   // Test for case-insensitive match of a literal character.
132                               //   Operand:  the literal char.
133     URX_STRING_I      = 40,   // Case insensitive string compare.
134                               //   First Operand:  Index of start of string in string literals
135                               //   Second Operand (next word in compiled code):
136                               //     the length of the string.
137     URX_BACKREF_I     = 41,   // Case insensitive back reference.
138                               //   Parameter is the index of the
139                               //   capture group variables in the state stack frame.
140     URX_DOLLAR_M      = 42,   // $ in multi-line mode.
141     URX_CARET_M       = 43,   // ^ in multi-line mode.
142     URX_LB_START      = 44,   // LookBehind Start.
143                               //   Paramater is data location
144     URX_LB_CONT       = 45,   // LookBehind Continue.
145                               //   Param 0:  the data location
146                               //   Param 1:  The minimum length of the look-behind match
147                               //   Param 2:  The max length of the look-behind match
148     URX_LB_END        = 46,   // LookBehind End.
149                               //   Parameter is the data location.
150                               //     Check that match ended at the right spot,
151                               //     Restore original input string len.
152     URX_LBN_CONT      = 47,   // Negative LookBehind Continue
153                               //   Param 0:  the data location
154                               //   Param 1:  The minimum length of the look-behind match
155                               //   Param 2:  The max     length of the look-behind match
156                               //   Param 3:  The pattern loc following the look-behind block.
157     URX_LBN_END       = 48,   // Negative LookBehind end
158                               //   Parameter is the data location.
159                               //   Check that the match ended at the right spot.
160     URX_STAT_SETREF_N = 49,   // Reference to a prebuilt set (e.g. \w), negated
161                               //   Operand is index of set in array of sets.
162     URX_LOOP_SR_I     = 50,   // Init a [set]* loop.
163                               //   Operand is the sets index in array of user sets.
164     URX_LOOP_C        = 51,   // Continue a [set]* or OneChar* loop.
165                               //   Operand is a matcher static data location.
166                               //   Must always immediately follow  LOOP_x_I instruction.
167     URX_LOOP_DOT_I    = 52,   // .*, initialization of the optimized loop.
168                               //   Operand value:
169                               //      bit 0:
170                               //         0:  Normal (. doesn't match new-line) mode.
171                               //         1:  . matches new-line mode.
172                               //      bit 1:  controls what new-lines are recognized by this operation.
173                               //         0:  All Unicode New-lines
174                               //         1:  UNIX_LINES, \u000a only.
175     URX_BACKSLASH_BU  = 53,   // \b or \B in UREGEX_UWORD mode, using Unicode style
176                               //   word boundaries.
177     URX_DOLLAR_D      = 54,   // $ end of input test, in UNIX_LINES mode.
178     URX_DOLLAR_MD     = 55,   // $ end of input test, in MULTI_LINE and UNIX_LINES mode.
179     URX_BACKSLASH_H   = 56,   // Value field:  0:  \h    1:  \H
180     URX_BACKSLASH_R   = 57,   // Any line break sequence.
181     URX_BACKSLASH_V   = 58    // Value field:  0:  \v    1:  \V
182
183};
184
185// Keep this list of opcode names in sync with the above enum
186//   Used for debug printing only.
187#define URX_OPCODE_NAMES       \
188        "               ",     \
189        "BACKTRACK",           \
190        "END",                 \
191        "ONECHAR",             \
192        "STRING",              \
193        "STRING_LEN",          \
194        "STATE_SAVE",          \
195        "NOP",                 \
196        "START_CAPTURE",       \
197        "END_CAPTURE",         \
198        "URX_STATIC_SETREF",   \
199        "SETREF",              \
200        "DOTANY",              \
201        "JMP",                 \
202        "FAIL",                \
203        "JMP_SAV",             \
204        "BACKSLASH_B",         \
205        "BACKSLASH_G",         \
206        "JMP_SAV_X",           \
207        "BACKSLASH_X",         \
208        "BACKSLASH_Z",         \
209        "DOTANY_ALL",          \
210        "BACKSLASH_D",         \
211        "CARET",               \
212        "DOLLAR",              \
213        "CTR_INIT",            \
214        "CTR_INIT_NG",         \
215        "DOTANY_UNIX",         \
216        "CTR_LOOP",            \
217        "CTR_LOOP_NG",         \
218        "URX_CARET_M_UNIX",    \
219        "RELOC_OPRND",         \
220        "STO_SP",              \
221        "LD_SP",               \
222        "BACKREF",             \
223        "STO_INP_LOC",         \
224        "JMPX",                \
225        "LA_START",            \
226        "LA_END",              \
227        "ONECHAR_I",           \
228        "STRING_I",            \
229        "BACKREF_I",           \
230        "DOLLAR_M",            \
231        "CARET_M",             \
232        "LB_START",            \
233        "LB_CONT",             \
234        "LB_END",              \
235        "LBN_CONT",            \
236        "LBN_END",             \
237        "STAT_SETREF_N",       \
238        "LOOP_SR_I",           \
239        "LOOP_C",              \
240        "LOOP_DOT_I",          \
241        "BACKSLASH_BU",        \
242        "DOLLAR_D",            \
243        "DOLLAR_MD",           \
244        "URX_BACKSLASH_H",     \
245        "URX_BACKSLASH_R",     \
246        "URX_BACKSLASH_V"
247
248
249//
250//  Convenience macros for assembling and disassembling a compiled operation.
251//
252#define URX_TYPE(x)          ((uint32_t)(x) >> 24)
253#define URX_VAL(x)           ((x) & 0xffffff)
254
255
256//
257//  Access to Unicode Sets composite character properties
258//     The sets are accessed by the match engine for things like \w (word boundary)
259//
260enum {
261     URX_ISWORD_SET  = 1,
262     URX_ISALNUM_SET = 2,
263     URX_ISALPHA_SET = 3,
264     URX_ISSPACE_SET = 4,
265
266     URX_GC_NORMAL,          // Sets for finding grapheme cluster boundaries.
267     URX_GC_EXTEND,
268     URX_GC_CONTROL,
269     URX_GC_L,
270     URX_GC_LV,
271     URX_GC_LVT,
272     URX_GC_V,
273     URX_GC_T,
274
275     URX_LAST_SET,
276
277     URX_NEG_SET     = 0x800000          // Flag bit to reverse sense of set
278                                         //   membership test.
279};
280
281
282//
283//  Match Engine State Stack Frame Layout.
284//
285struct REStackFrame {
286    // Header
287    int64_t            fInputIdx;        // Position of next character in the input string
288    int64_t            fPatIdx;          // Position of next Op in the compiled pattern
289                                         // (int64_t for UVector64, values fit in an int32_t)
290    // Remainder
291    int64_t            fExtra[1];        // Extra state, for capture group start/ends
292                                         //   atomic parentheses, repeat counts, etc.
293                                         //   Locations assigned at pattern compile time.
294                                         //   Variable-length array.
295};
296// number of UVector elements in the header
297#define RESTACKFRAME_HDRCOUNT 2
298
299//
300//  Start-Of-Match type.  Used by find() to quickly scan to positions where a
301//                        match might start before firing up the full match engine.
302//
303enum StartOfMatch {
304    START_NO_INFO,             // No hint available.
305    START_CHAR,                // Match starts with a literal code point.
306    START_SET,                 // Match starts with something matching a set.
307    START_START,               // Match starts at start of buffer only (^ or \A)
308    START_LINE,                // Match starts with ^ in multi-line mode.
309    START_STRING               // Match starts with a literal string.
310};
311
312#define START_OF_MATCH_STR(v) ((v)==START_NO_INFO? "START_NO_INFO" : \
313                               (v)==START_CHAR?    "START_CHAR"    : \
314                               (v)==START_SET?     "START_SET"     : \
315                               (v)==START_START?   "START_START"   : \
316                               (v)==START_LINE?    "START_LINE"    : \
317                               (v)==START_STRING?  "START_STRING"  : \
318                                                   "ILLEGAL")
319
320//
321//  8 bit set, to fast-path latin-1 set membership tests.
322//
323struct Regex8BitSet : public UMemory {
324    inline Regex8BitSet();
325    inline void operator = (const Regex8BitSet &s);
326    inline void init(const UnicodeSet *src);
327    inline UBool contains(UChar32 c);
328    inline void  add(UChar32 c);
329    int8_t d[32];
330};
331
332inline Regex8BitSet::Regex8BitSet() {
333    uprv_memset(d, 0, sizeof(d));
334}
335
336inline UBool Regex8BitSet::contains(UChar32 c) {
337    // No bounds checking!  This is deliberate.
338    return ((d[c>>3] & 1 <<(c&7)) != 0);
339}
340
341inline void  Regex8BitSet::add(UChar32 c) {
342    d[c>>3] |= 1 << (c&7);
343}
344
345inline void Regex8BitSet::init(const UnicodeSet *s) {
346    if (s != NULL) {
347        for (int32_t i=0; i<=255; i++) {
348            if (s->contains(i)) {
349                this->add(i);
350            }
351        }
352    }
353}
354
355inline void Regex8BitSet::operator = (const Regex8BitSet &s) {
356   uprv_memcpy(d, s.d, sizeof(d));
357}
358
359
360//  Case folded UText Iterator helper class.
361//  Wraps a UText, provides a case-folded enumeration over its contents.
362//  Used in implementing case insensitive matching constructs.
363//  Implementation in rematch.cpp
364
365class CaseFoldingUTextIterator: public UMemory {
366      public:
367        CaseFoldingUTextIterator(UText &text);
368        ~CaseFoldingUTextIterator();
369
370        UChar32 next();           // Next case folded character
371
372        UBool   inExpansion();    // True if last char returned from next() and the
373                                  //  next to be returned both originated from a string
374                                  //  folding of the same code point from the orignal UText.
375      private:
376        UText             &fUText;
377        const  UCaseProps *fcsp;
378        const  UChar      *fFoldChars;
379        int32_t            fFoldLength;
380        int32_t            fFoldIndex;
381
382};
383
384
385// Case folded UChar * string iterator.
386//  Wraps a UChar  *, provides a case-folded enumeration over its contents.
387//  Used in implementing case insensitive matching constructs.
388//  Implementation in rematch.cpp
389
390class CaseFoldingUCharIterator: public UMemory {
391      public:
392        CaseFoldingUCharIterator(const UChar *chars, int64_t start, int64_t limit);
393        ~CaseFoldingUCharIterator();
394
395        UChar32 next();           // Next case folded character
396
397        UBool   inExpansion();    // True if last char returned from next() and the
398                                  //  next to be returned both originated from a string
399                                  //  folding of the same code point from the orignal UText.
400
401        int64_t  getIndex();      // Return the current input buffer index.
402
403      private:
404        const  UChar      *fChars;
405        int64_t            fIndex;
406        int64_t            fLimit;
407        const  UCaseProps *fcsp;
408        const  UChar      *fFoldChars;
409        int32_t            fFoldLength;
410        int32_t            fFoldIndex;
411
412};
413
414U_NAMESPACE_END
415#endif
416
417