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      1 //
      2 //   Copyright (C) 2002-2010 International Business Machines Corporation
      3 //   and others. All rights reserved.
      4 //
      5 //   file:  regeximp.h
      6 //
      7 //           ICU Regular Expressions,
      8 //               Definitions of constant values used in the compiled form of
      9 //               a regular expression pattern.
     10 //
     11 
     12 #ifndef _REGEXIMP_H
     13 #define _REGEXIMP_H
     14 
     15 #include "cmemory.h"
     16 
     17 U_NAMESPACE_BEGIN
     18 
     19 #ifdef REGEX_DEBUG   /* For debugging, define REGEX_DEBUG in regex.h, not here in this file. */
     20 //
     21 //  debugging options.  Enable one or more of the three #defines immediately following
     22 //
     23 
     24 //#define REGEX_SCAN_DEBUG
     25 #define REGEX_DUMP_DEBUG
     26 #define REGEX_RUN_DEBUG
     27 
     28 //  End of #defines inteded to be directly set.
     29 
     30 #include <stdio.h>
     31 #endif
     32 
     33 #ifdef REGEX_SCAN_DEBUG
     34 #define REGEX_SCAN_DEBUG_PRINTF(a) printf a
     35 #else
     36 #define REGEX_SCAN_DEBUG_PRINTF(a)
     37 #endif
     38 
     39 #ifdef REGEX_DUMP_DEBUG
     40 #define REGEX_DUMP_DEBUG_PRINTF(a) printf a
     41 #else
     42 #define REGEX_DUMP_DEBUG_PRINTF(a)
     43 #endif
     44 
     45 #ifdef REGEX_RUN_DEBUG
     46 #define REGEX_RUN_DEBUG_PRINTF(a) printf a
     47 #define REGEX_DUMP_DEBUG_PRINTF(a) printf a
     48 #else
     49 #define REGEX_RUN_DEBUG_PRINTF(a)
     50 #endif
     51 
     52 
     53 //
     54 //  Opcode types     In the compiled form of the regexp, these are the type, or opcodes,
     55 //                   of the entries.
     56 //
     57 enum {
     58      URX_RESERVED_OP   = 0,    // For multi-operand ops, most non-first words.
     59      URX_RESERVED_OP_N = 255,  // For multi-operand ops, negative operand values.
     60      URX_BACKTRACK     = 1,    // Force a backtrack, as if a match test had failed.
     61      URX_END           = 2,
     62      URX_ONECHAR       = 3,    // Value field is the 21 bit unicode char to match
     63      URX_STRING        = 4,    // Value field is index of string start
     64      URX_STRING_LEN    = 5,    // Value field is string length (code units)
     65      URX_STATE_SAVE    = 6,    // Value field is pattern position to push
     66      URX_NOP           = 7,
     67      URX_START_CAPTURE = 8,    // Value field is capture group number.
     68      URX_END_CAPTURE   = 9,    // Value field is capture group number
     69      URX_STATIC_SETREF = 10,   // Value field is index of set in array of sets.
     70      URX_SETREF        = 11,   // Value field is index of set in array of sets.
     71      URX_DOTANY        = 12,
     72      URX_JMP           = 13,   // Value field is destination position in
     73                                                     //   the pattern.
     74      URX_FAIL          = 14,   // Stop match operation,  No match.
     75 
     76      URX_JMP_SAV       = 15,   // Operand:  JMP destination location
     77      URX_BACKSLASH_B   = 16,   // Value field:  0:  \b    1:  \B
     78      URX_BACKSLASH_G   = 17,
     79      URX_JMP_SAV_X     = 18,   // Conditional JMP_SAV,
     80                                //    Used in (x)+, breaks loop on zero length match.
     81                                //    Operand:  Jmp destination.
     82      URX_BACKSLASH_X   = 19,
     83      URX_BACKSLASH_Z   = 20,   // \z   Unconditional end of line.
     84 
     85      URX_DOTANY_ALL    = 21,   // ., in the . matches any mode.
     86      URX_BACKSLASH_D   = 22,   // Value field:  0:  \d    1:  \D
     87      URX_CARET         = 23,   // Value field:  1:  multi-line mode.
     88      URX_DOLLAR        = 24,  // Also for \Z
     89 
     90      URX_CTR_INIT      = 25,   // Counter Inits for {Interval} loops.
     91      URX_CTR_INIT_NG   = 26,   //   2 kinds, normal and non-greedy.
     92                                //   These are 4 word opcodes.  See description.
     93                                //    First Operand:  Data loc of counter variable
     94                                //    2nd   Operand:  Pat loc of the URX_CTR_LOOPx
     95                                //                    at the end of the loop.
     96                                //    3rd   Operand:  Minimum count.
     97                                //    4th   Operand:  Max count, -1 for unbounded.
     98 
     99      URX_DOTANY_UNIX   = 27,   // '.' operator in UNIX_LINES mode, only \n marks end of line.
    100 
    101      URX_CTR_LOOP      = 28,   // Loop Ops for {interval} loops.
    102      URX_CTR_LOOP_NG   = 29,   //   Also in three flavors.
    103                                //   Operand is loc of corresponding CTR_INIT.
    104 
    105      URX_CARET_M_UNIX  = 30,   // '^' operator, test for start of line in multi-line
    106                                //      plus UNIX_LINES mode.
    107 
    108      URX_RELOC_OPRND   = 31,   // Operand value in multi-operand ops that refers
    109                                //   back into compiled pattern code, and thus must
    110                                //   be relocated when inserting/deleting ops in code.
    111 
    112      URX_STO_SP        = 32,   // Store the stack ptr.  Operand is location within
    113                                //   matcher data (not stack data) to store it.
    114      URX_LD_SP         = 33,   // Load the stack pointer.  Operand is location
    115                                //   to load from.
    116      URX_BACKREF       = 34,   // Back Reference.  Parameter is the index of the
    117                                //   capture group variables in the state stack frame.
    118      URX_STO_INP_LOC   = 35,   // Store the input location.  Operand is location
    119                                //   within the matcher stack frame.
    120      URX_JMPX          = 36,  // Conditional JMP.
    121                                //   First Operand:  JMP target location.
    122                                //   Second Operand:  Data location containing an
    123                                //     input position.  If current input position ==
    124                                //     saved input position, FAIL rather than taking
    125                                //     the JMP
    126      URX_LA_START      = 37,   // Starting a LookAround expression.
    127                                //   Save InputPos and SP in static data.
    128                                //   Operand:  Static data offset for the save
    129      URX_LA_END        = 38,   // Ending a Lookaround expression.
    130                                //   Restore InputPos and Stack to saved values.
    131                                //   Operand:  Static data offset for saved data.
    132      URX_ONECHAR_I     = 39,   // Test for case-insensitive match of a literal character.
    133                                //   Operand:  the literal char.
    134      URX_STRING_I      = 40,   // Case insensitive string compare.
    135                                //   First Operand:  Index of start of string in string literals
    136                                //   Second Operand (next word in compiled code):
    137                                //     the length of the string.
    138      URX_BACKREF_I     = 41,   // Case insensitive back reference.
    139                                //   Parameter is the index of the
    140                                //   capture group variables in the state stack frame.
    141      URX_DOLLAR_M      = 42,   // $ in multi-line mode.
    142      URX_CARET_M       = 43,   // ^ in multi-line mode.
    143      URX_LB_START      = 44,   // LookBehind Start.
    144                                //   Paramater is data location
    145      URX_LB_CONT       = 45,   // LookBehind Continue.
    146                                //   Param 0:  the data location
    147                                //   Param 1:  The minimum length of the look-behind match
    148                                //   Param 2:  The max length of the look-behind match
    149      URX_LB_END        = 46,   // LookBehind End.
    150                                //   Parameter is the data location.
    151                                //     Check that match ended at the right spot,
    152                                //     Restore original input string len.
    153      URX_LBN_CONT      = 47,   // Negative LookBehind Continue
    154                                //   Param 0:  the data location
    155                                //   Param 1:  The minimum length of the look-behind match
    156                                //   Param 2:  The max     length of the look-behind match
    157                                //   Param 3:  The pattern loc following the look-behind block.
    158      URX_LBN_END       = 48,   // Negative LookBehind end
    159                                //   Parameter is the data location.
    160                                //   Check that the match ended at the right spot.
    161      URX_STAT_SETREF_N = 49,   // Reference to a prebuilt set (e.g. \w), negated
    162                                //   Operand is index of set in array of sets.
    163      URX_LOOP_SR_I     = 50,   // Init a [set]* loop.
    164                                //   Operand is the sets index in array of user sets.
    165      URX_LOOP_C        = 51,   // Continue a [set]* or OneChar* loop.
    166                                //   Operand is a matcher static data location.
    167                                //   Must always immediately follow  LOOP_x_I instruction.
    168      URX_LOOP_DOT_I    = 52,   // .*, initialization of the optimized loop.
    169                                //   Operand value:
    170                                //      bit 0:
    171                                //         0:  Normal (. doesn't match new-line) mode.
    172                                //         1:  . matches new-line mode.
    173                                //      bit 1:  controls what new-lines are recognized by this operation.
    174                                //         0:  All Unicode New-lines
    175                                //         1:  UNIX_LINES, \u000a only.
    176      URX_BACKSLASH_BU  = 53,   // \b or \B in UREGEX_UWORD mode, using Unicode style
    177                                //   word boundaries.
    178      URX_DOLLAR_D      = 54,   // $ end of input test, in UNIX_LINES mode.
    179      URX_DOLLAR_MD     = 55    // $ end of input test, in MULTI_LINE and UNIX_LINES mode.
    180 
    181 };
    182 
    183 // Keep this list of opcode names in sync with the above enum
    184 //   Used for debug printing only.
    185 #define URX_OPCODE_NAMES       \
    186         "               ",     \
    187         "BACKTRACK",           \
    188         "END",                 \
    189         "ONECHAR",             \
    190         "STRING",              \
    191         "STRING_LEN",          \
    192         "STATE_SAVE",          \
    193         "NOP",                 \
    194         "START_CAPTURE",       \
    195         "END_CAPTURE",         \
    196         "URX_STATIC_SETREF",   \
    197         "SETREF",              \
    198         "DOTANY",              \
    199         "JMP",                 \
    200         "FAIL",                \
    201         "JMP_SAV",             \
    202         "BACKSLASH_B",         \
    203         "BACKSLASH_G",         \
    204         "JMP_SAV_X",           \
    205         "BACKSLASH_X",         \
    206         "BACKSLASH_Z",         \
    207         "DOTANY_ALL",          \
    208         "BACKSLASH_D",         \
    209         "CARET",               \
    210         "DOLLAR",              \
    211         "CTR_INIT",            \
    212         "CTR_INIT_NG",         \
    213         "DOTANY_UNIX",         \
    214         "CTR_LOOP",            \
    215         "CTR_LOOP_NG",         \
    216         "URX_CARET_M_UNIX",    \
    217         "RELOC_OPRND",         \
    218         "STO_SP",              \
    219         "LD_SP",               \
    220         "BACKREF",             \
    221         "STO_INP_LOC",         \
    222         "JMPX",                \
    223         "LA_START",            \
    224         "LA_END",              \
    225         "ONECHAR_I",           \
    226         "STRING_I",            \
    227         "BACKREF_I",           \
    228         "DOLLAR_M",            \
    229         "CARET_M",             \
    230         "LB_START",            \
    231         "LB_CONT",             \
    232         "LB_END",              \
    233         "LBN_CONT",            \
    234         "LBN_END",             \
    235         "STAT_SETREF_N",       \
    236         "LOOP_SR_I",           \
    237         "LOOP_C",              \
    238         "LOOP_DOT_I",          \
    239         "BACKSLASH_BU",        \
    240         "DOLLAR_D",            \
    241         "DOLLAR_MD"
    242 
    243 
    244 //
    245 //  Convenience macros for assembling and disassembling a compiled operation.
    246 //
    247 #define URX_BUILD(type, val) (int32_t)((type << 24) | (val))
    248 #define URX_TYPE(x)          ((uint32_t)(x) >> 24)
    249 #define URX_VAL(x)           ((x) & 0xffffff)
    250 
    251 
    252 //
    253 //  Access to Unicode Sets composite character properties
    254 //     The sets are accessed by the match engine for things like \w (word boundary)
    255 //
    256 enum {
    257      URX_ISWORD_SET  = 1,
    258      URX_ISALNUM_SET = 2,
    259      URX_ISALPHA_SET = 3,
    260      URX_ISSPACE_SET = 4,
    261 
    262      URX_GC_NORMAL,          // Sets for finding grapheme cluster boundaries.
    263      URX_GC_EXTEND,
    264      URX_GC_CONTROL,
    265      URX_GC_L,
    266      URX_GC_LV,
    267      URX_GC_LVT,
    268      URX_GC_V,
    269      URX_GC_T,
    270 
    271      URX_LAST_SET,
    272 
    273      URX_NEG_SET     = 0x800000          // Flag bit to reverse sense of set
    274                                          //   membership test.
    275 };
    276 
    277 
    278 //
    279 //  Match Engine State Stack Frame Layout.
    280 //
    281 struct REStackFrame {
    282     // Header
    283     int64_t            fInputIdx;        // Position of next character in the input string
    284     int64_t            fPatIdx;          // Position of next Op in the compiled pattern
    285                                          // (int64_t for UVector64, values fit in an int32_t)
    286     // Remainder
    287     int64_t            fExtra[1];        // Extra state, for capture group start/ends
    288                                          //   atomic parentheses, repeat counts, etc.
    289                                          //   Locations assigned at pattern compile time.
    290                                          //   Variable-length array.
    291 };
    292 // number of UVector elements in the header
    293 #define RESTACKFRAME_HDRCOUNT 2
    294 
    295 //
    296 //  Start-Of-Match type.  Used by find() to quickly scan to positions where a
    297 //                        match might start before firing up the full match engine.
    298 //
    299 enum StartOfMatch {
    300     START_NO_INFO,             // No hint available.
    301     START_CHAR,                // Match starts with a literal code point.
    302     START_SET,                 // Match starts with something matching a set.
    303     START_START,               // Match starts at start of buffer only (^ or \A)
    304     START_LINE,                // Match starts with ^ in multi-line mode.
    305     START_STRING               // Match starts with a literal string.
    306 };
    307 
    308 #define START_OF_MATCH_STR(v) ((v)==START_NO_INFO? "START_NO_INFO" : \
    309                                (v)==START_CHAR?    "START_CHAR"    : \
    310                                (v)==START_SET?     "START_SET"     : \
    311                                (v)==START_START?   "START_START"   : \
    312                                (v)==START_LINE?    "START_LINE"    : \
    313                                (v)==START_STRING?  "START_STRING"  : \
    314                                                    "ILLEGAL")
    315 
    316 //
    317 //  8 bit set, to fast-path latin-1 set membership tests.
    318 //
    319 struct Regex8BitSet : public UMemory {
    320     inline Regex8BitSet();
    321     inline void operator = (const Regex8BitSet &s);
    322     inline void init(const UnicodeSet *src);
    323     inline UBool contains(UChar32 c);
    324     inline void  add(UChar32 c);
    325     int8_t d[32];
    326 };
    327 
    328 inline Regex8BitSet::Regex8BitSet() {
    329     uprv_memset(d, 0, sizeof(d));
    330 }
    331 
    332 inline UBool Regex8BitSet::contains(UChar32 c) {
    333     // No bounds checking!  This is deliberate.
    334     return ((d[c>>3] & 1 <<(c&7)) != 0);
    335 }
    336 
    337 inline void  Regex8BitSet::add(UChar32 c) {
    338     d[c>>3] |= 1 << (c&7);
    339 }
    340 
    341 inline void Regex8BitSet::init(const UnicodeSet *s) {
    342     if (s != NULL) {
    343         for (int32_t i=0; i<=255; i++) {
    344             if (s->contains(i)) {
    345                 this->add(i);
    346             }
    347         }
    348     }
    349 }
    350 
    351 inline void Regex8BitSet::operator = (const Regex8BitSet &s) {
    352    uprv_memcpy(d, s.d, sizeof(d));
    353 }
    354 
    355 U_NAMESPACE_END
    356 #endif
    357 
    358