lib/perl5/5.8.8/msys/CORE/regcomp.h

   1 /*    regcomp.h
   2  *
   3  *    Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
   4  *    2000, 2001, 2002, 2003, 2005 by Larry Wall and others
   5  *
   6  *    You may distribute under the terms of either the GNU General Public
   7  *    License or the Artistic License, as specified in the README file.
   8  *
   9  */
  10
  11 typedef OP OP_4tree;                    /* Will be redefined later. */
  12
  13 /*
  14  * The "internal use only" fields in regexp.h are present to pass info from
  15  * compile to execute that permits the execute phase to run lots faster on
  16  * simple cases.  They are:
  17  *
  18  * regstart     sv that must begin a match; Nullch if none obvious
  19  * reganch      is the match anchored (at beginning-of-line only)?
  20  * regmust      string (pointer into program) that match must include, or NULL
  21  *  [regmust changed to SV* for bminstr()--law]
  22  * regmlen      length of regmust string
  23  *  [regmlen not used currently]
  24  *
  25  * Regstart and reganch permit very fast decisions on suitable starting points
  26  * for a match, cutting down the work a lot.  Regmust permits fast rejection
  27  * of lines that cannot possibly match.  The regmust tests are costly enough
  28  * that pregcomp() supplies a regmust only if the r.e. contains something
  29  * potentially expensive (at present, the only such thing detected is * or +
  30  * at the start of the r.e., which can involve a lot of backup).  Regmlen is
  31  * supplied because the test in pregexec() needs it and pregcomp() is computing
  32  * it anyway.
  33  * [regmust is now supplied always.  The tests that use regmust have a
  34  * heuristic that disables the test if it usually matches.]
  35  *
  36  * [In fact, we now use regmust in many cases to locate where the search
  37  * starts in the string, so if regback is >= 0, the regmust search is never
  38  * wasted effort.  The regback variable says how many characters back from
  39  * where regmust matched is the earliest possible start of the match.
  40  * For instance, /[a-z].foo/ has a regmust of 'foo' and a regback of 2.]
  41  */
  42
  43 /*
  44  * Structure for regexp "program".  This is essentially a linear encoding
  45  * of a nondeterministic finite-state machine (aka syntax charts or
  46  * "railroad normal form" in parsing technology).  Each node is an opcode
  47  * plus a "next" pointer, possibly plus an operand.  "Next" pointers of
  48  * all nodes except BRANCH implement concatenation; a "next" pointer with
  49  * a BRANCH on both ends of it is connecting two alternatives.  (Here we
  50  * have one of the subtle syntax dependencies:  an individual BRANCH (as
  51  * opposed to a collection of them) is never concatenated with anything
  52  * because of operator precedence.)  The operand of some types of node is
  53  * a literal string; for others, it is a node leading into a sub-FSM.  In
  54  * particular, the operand of a BRANCH node is the first node of the branch.
  55  * (NB this is *not* a tree structure:  the tail of the branch connects
  56  * to the thing following the set of BRANCHes.)  The opcodes are:
  57  */
  58
  59 /*
  60  * A node is one char of opcode followed by two chars of "next" pointer.
  61  * "Next" pointers are stored as two 8-bit pieces, high order first.  The
  62  * value is a positive offset from the opcode of the node containing it.
  63  * An operand, if any, simply follows the node.  (Note that much of the
  64  * code generation knows about this implicit relationship.)
  65  *
  66  * Using two bytes for the "next" pointer is vast overkill for most things,
  67  * but allows patterns to get big without disasters.
  68  *
  69  * [The "next" pointer is always aligned on an even
  70  * boundary, and reads the offset directly as a short.  Also, there is no
  71  * special test to reverse the sign of BACK pointers since the offset is
  72  * stored negative.]
  73  */
  74
  75 struct regnode_string {
  76     U8  str_len;
  77     U8  type;
  78     U16 next_off;
  79     char string[1];
  80 };
  81
  82 struct regnode_1 {
  83     U8  flags;
  84     U8  type;
  85     U16 next_off;
  86     U32 arg1;
  87 };
  88
  89 struct regnode_2 {
  90     U8  flags;
  91     U8  type;
  92     U16 next_off;
  93     U16 arg1;
  94     U16 arg2;
  95 };
  96
  97 #define ANYOF_BITMAP_SIZE       32      /* 256 b/(8 b/B) */
  98 #define ANYOF_CLASSBITMAP_SIZE   4      /* up to 32 (8*4) named classes */
  99
 100 struct regnode_charclass {
 101     U8  flags;
 102     U8  type;
 103     U16 next_off;
 104     U32 arg1;
 105     char bitmap[ANYOF_BITMAP_SIZE];     /* only compile-time */
 106 };
 107
 108 struct regnode_charclass_class {        /* has [[:blah:]] classes */
 109     U8  flags;                          /* should have ANYOF_CLASS here */
 110     U8  type;
 111     U16 next_off;
 112     U32 arg1;
 113     char bitmap[ANYOF_BITMAP_SIZE];             /* both compile-time */
 114     char classflags[ANYOF_CLASSBITMAP_SIZE];    /* and run-time */
 115 };
 116
 117 /* XXX fix this description.
 118    Impose a limit of REG_INFTY on various pattern matching operations
 119    to limit stack growth and to avoid "infinite" recursions.
 120 */
 121 /* The default size for REG_INFTY is I16_MAX, which is the same as
 122    SHORT_MAX (see perl.h).  Unfortunately I16 isn't necessarily 16 bits
 123    (see handy.h).  On the Cray C90, sizeof(short)==4 and hence I16_MAX is
 124    ((1<<31)-1), while on the Cray T90, sizeof(short)==8 and I16_MAX is
 125    ((1<<63)-1).  To limit stack growth to reasonable sizes, supply a
 126    smaller default.
 127         --Andy Dougherty  11 June 1998
 128 */
 129 #if SHORTSIZE > 2
 130 #  ifndef REG_INFTY
 131 #    define REG_INFTY ((1<<15)-1)
 132 #  endif
 133 #endif
 134
 135 #ifndef REG_INFTY
 136 #  define REG_INFTY I16_MAX
 137 #endif
 138
 139 #define ARG_VALUE(arg) (arg)
 140 #define ARG__SET(arg,val) ((arg) = (val))
 141
 142 #undef ARG
 143 #undef ARG1
 144 #undef ARG2
 145
 146 #define ARG(p) ARG_VALUE(ARG_LOC(p))
 147 #define ARG1(p) ARG_VALUE(ARG1_LOC(p))
 148 #define ARG2(p) ARG_VALUE(ARG2_LOC(p))
 149 #define ARG_SET(p, val) ARG__SET(ARG_LOC(p), (val))
 150 #define ARG1_SET(p, val) ARG__SET(ARG1_LOC(p), (val))
 151 #define ARG2_SET(p, val) ARG__SET(ARG2_LOC(p), (val))
 152
 153 #undef NEXT_OFF
 154 #undef NODE_ALIGN
 155
 156 #define NEXT_OFF(p) ((p)->next_off)
 157 #define NODE_ALIGN(node)
 158 #define NODE_ALIGN_FILL(node) ((node)->flags = 0xde) /* deadbeef */
 159
 160 #define SIZE_ALIGN NODE_ALIGN
 161
 162 #undef OP
 163 #undef OPERAND
 164 #undef MASK
 165 #undef STRING
 166
 167 #define OP(p)           ((p)->type)
 168 #define OPERAND(p)      (((struct regnode_string *)p)->string)
 169 #define MASK(p)         ((char*)OPERAND(p))
 170 #define STR_LEN(p)      (((struct regnode_string *)p)->str_len)
 171 #define STRING(p)       (((struct regnode_string *)p)->string)
 172 #define STR_SZ(l)       ((l + sizeof(regnode) - 1) / sizeof(regnode))
 173 #define NODE_SZ_STR(p)  (STR_SZ(STR_LEN(p))+1)
 174
 175 #undef NODE_ALIGN
 176 #undef ARG_LOC
 177 #undef NEXTOPER
 178 #undef PREVOPER
 179
 180 #define NODE_ALIGN(node)
 181 #define ARG_LOC(p)      (((struct regnode_1 *)p)->arg1)
 182 #define ARG1_LOC(p)     (((struct regnode_2 *)p)->arg1)
 183 #define ARG2_LOC(p)     (((struct regnode_2 *)p)->arg2)
 184 #define NODE_STEP_REGNODE       1       /* sizeof(regnode)/sizeof(regnode) */
 185 #define EXTRA_STEP_2ARGS        EXTRA_SIZE(struct regnode_2)
 186
 187 #define NODE_STEP_B     4
 188
 189 #define NEXTOPER(p)     ((p) + NODE_STEP_REGNODE)
 190 #define PREVOPER(p)     ((p) - NODE_STEP_REGNODE)
 191
 192 #define FILL_ADVANCE_NODE(ptr, op) STMT_START { \
 193     (ptr)->type = op;    (ptr)->next_off = 0;   (ptr)++; } STMT_END
 194 #define FILL_ADVANCE_NODE_ARG(ptr, op, arg) STMT_START { \
 195     ARG_SET(ptr, arg);  FILL_ADVANCE_NODE(ptr, op); (ptr) += 1; } STMT_END
 196
 197 #define REG_MAGIC 0234
 198
 199 #define SIZE_ONLY (RExC_emit == &PL_regdummy)
 200
 201 /* Flags for node->flags of ANYOF */
 202
 203 #define ANYOF_CLASS             0x08    /* has [[:blah:]] classes */
 204 #define ANYOF_INVERT            0x04
 205 #define ANYOF_FOLD              0x02
 206 #define ANYOF_LOCALE            0x01
 207
 208 /* Used for regstclass only */
 209 #define ANYOF_EOS               0x10            /* Can match an empty string too */
 210
 211 /* There is a character or a range past 0xff */
 212 #define ANYOF_UNICODE           0x20
 213 #define ANYOF_UNICODE_ALL       0x40    /* Can match any char past 0xff */
 214
 215 /* size of node is large (includes class pointer) */
 216 #define ANYOF_LARGE             0x80
 217
 218 /* Are there any runtime flags on in this node? */
 219 #define ANYOF_RUNTIME(s)        (ANYOF_FLAGS(s) & 0x0f)
 220
 221 #define ANYOF_FLAGS_ALL         0xff
 222
 223 /* Character classes for node->classflags of ANYOF */
 224 /* Should be synchronized with a table in regprop() */
 225 /* 2n should pair with 2n+1 */
 226
 227 #define ANYOF_ALNUM      0      /* \w, PL_utf8_alnum, utf8::IsWord, ALNUM */
 228 #define ANYOF_NALNUM     1
 229 #define ANYOF_SPACE      2      /* \s */
 230 #define ANYOF_NSPACE     3
 231 #define ANYOF_DIGIT      4
 232 #define ANYOF_NDIGIT     5
 233 #define ANYOF_ALNUMC     6      /* isalnum(3), utf8::IsAlnum, ALNUMC */
 234 #define ANYOF_NALNUMC    7
 235 #define ANYOF_ALPHA      8
 236 #define ANYOF_NALPHA     9
 237 #define ANYOF_ASCII     10
 238 #define ANYOF_NASCII    11
 239 #define ANYOF_CNTRL     12
 240 #define ANYOF_NCNTRL    13
 241 #define ANYOF_GRAPH     14
 242 #define ANYOF_NGRAPH    15
 243 #define ANYOF_LOWER     16
 244 #define ANYOF_NLOWER    17
 245 #define ANYOF_PRINT     18
 246 #define ANYOF_NPRINT    19
 247 #define ANYOF_PUNCT     20
 248 #define ANYOF_NPUNCT    21
 249 #define ANYOF_UPPER     22
 250 #define ANYOF_NUPPER    23
 251 #define ANYOF_XDIGIT    24
 252 #define ANYOF_NXDIGIT   25
 253 #define ANYOF_PSXSPC    26      /* POSIX space: \s plus the vertical tab */
 254 #define ANYOF_NPSXSPC   27
 255 #define ANYOF_BLANK     28      /* GNU extension: space and tab: non-vertical space */
 256 #define ANYOF_NBLANK    29
 257
 258 #define ANYOF_MAX       32
 259
 260 /* Backward source code compatibility. */
 261
 262 #define ANYOF_ALNUML     ANYOF_ALNUM
 263 #define ANYOF_NALNUML    ANYOF_NALNUM
 264 #define ANYOF_SPACEL     ANYOF_SPACE
 265 #define ANYOF_NSPACEL    ANYOF_NSPACE
 266
 267 /* Utility macros for the bitmap and classes of ANYOF */
 268
 269 #define ANYOF_SIZE              (sizeof(struct regnode_charclass))
 270 #define ANYOF_CLASS_SIZE        (sizeof(struct regnode_charclass_class))
 271
 272 #define ANYOF_FLAGS(p)          ((p)->flags)
 273
 274 #define ANYOF_BIT(c)            (1 << ((c) & 7))
 275
 276 #define ANYOF_CLASS_BYTE(p, c)  (((struct regnode_charclass_class*)(p))->classflags[((c) >> 3) & 3])
 277 #define ANYOF_CLASS_SET(p, c)   (ANYOF_CLASS_BYTE(p, c) |=  ANYOF_BIT(c))
 278 #define ANYOF_CLASS_CLEAR(p, c) (ANYOF_CLASS_BYTE(p, c) &= ~ANYOF_BIT(c))
 279 #define ANYOF_CLASS_TEST(p, c)  (ANYOF_CLASS_BYTE(p, c) &   ANYOF_BIT(c))
 280
 281 #define ANYOF_CLASS_ZERO(ret)   Zero(((struct regnode_charclass_class*)(ret))->classflags, ANYOF_CLASSBITMAP_SIZE, char)
 282 #define ANYOF_BITMAP_ZERO(ret)  Zero(((struct regnode_charclass*)(ret))->bitmap, ANYOF_BITMAP_SIZE, char)
 283
 284 #define ANYOF_BITMAP(p)         (((struct regnode_charclass*)(p))->bitmap)
 285 #define ANYOF_BITMAP_BYTE(p, c) (ANYOF_BITMAP(p)[((c) >> 3) & 31])
 286 #define ANYOF_BITMAP_SET(p, c)  (ANYOF_BITMAP_BYTE(p, c) |=  ANYOF_BIT(c))
 287 #define ANYOF_BITMAP_CLEAR(p,c) (ANYOF_BITMAP_BYTE(p, c) &= ~ANYOF_BIT(c))
 288 #define ANYOF_BITMAP_TEST(p, c) (ANYOF_BITMAP_BYTE(p, c) &   ANYOF_BIT(c))
 289
 290 #define ANYOF_BITMAP_SETALL(p)          \
 291         memset (ANYOF_BITMAP(p), 255, ANYOF_BITMAP_SIZE)
 292 #define ANYOF_BITMAP_CLEARALL(p)        \
 293         Zero (ANYOF_BITMAP(p), ANYOF_BITMAP_SIZE)
 294 /* Check that all 256 bits are all set.  Used in S_cl_is_anything()  */
 295 #define ANYOF_BITMAP_TESTALLSET(p)      \
 296         memEQ (ANYOF_BITMAP(p), "\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377", ANYOF_BITMAP_SIZE)
 297
 298 #define ANYOF_SKIP              ((ANYOF_SIZE - 1)/sizeof(regnode))
 299 #define ANYOF_CLASS_SKIP        ((ANYOF_CLASS_SIZE - 1)/sizeof(regnode))
 300 #define ANYOF_CLASS_ADD_SKIP    (ANYOF_CLASS_SKIP - ANYOF_SKIP)
 301
 302 /*
 303  * Utility definitions.
 304  */
 305 #ifndef CHARMASK
 306 #  define UCHARAT(p)    ((int)*(const U8*)(p))
 307 #else
 308 #  define UCHARAT(p)    ((int)*(p)&CHARMASK)
 309 #endif
 310
 311 #define EXTRA_SIZE(guy) ((sizeof(guy)-1)/sizeof(struct regnode))
 312
 313 #define REG_SEEN_ZERO_LEN        1
 314 #define REG_SEEN_LOOKBEHIND      2
 315 #define REG_SEEN_GPOS            4
 316 #define REG_SEEN_EVAL            8
 317 #define REG_SEEN_CANY           16
 318 #define REG_SEEN_SANY           REG_SEEN_CANY /* src bckwrd cmpt */
 319
 320 START_EXTERN_C
 321
 322 #include "regnodes.h"
 323
 324 /* The following have no fixed length. U8 so we can do strchr() on it. */
 325 #ifndef DOINIT
 326 EXTCONST U8 PL_varies[];
 327 #else
 328 EXTCONST U8 PL_varies[] = {
 329     BRANCH, BACK, STAR, PLUS, CURLY, CURLYX, REF, REFF, REFFL,
 330     WHILEM, CURLYM, CURLYN, BRANCHJ, IFTHEN, SUSPEND, CLUMP, 0
 331 };
 332 #endif
 333
 334 /* The following always have a length of 1. U8 we can do strchr() on it. */
 335 /* (Note that length 1 means "one character" under UTF8, not "one octet".) */
 336 #ifndef DOINIT
 337 EXTCONST U8 PL_simple[];
 338 #else
 339 EXTCONST U8 PL_simple[] = {
 340     REG_ANY,    SANY,   CANY,
 341     ANYOF,
 342     ALNUM,      ALNUML,
 343     NALNUM,     NALNUML,
 344     SPACE,      SPACEL,
 345     NSPACE,     NSPACEL,
 346     DIGIT,      NDIGIT,
 347     0
 348 };
 349 #endif
 350
 351 END_EXTERN_C
 352
 353 typedef struct re_scream_pos_data_s
 354 {
 355     char **scream_olds;         /* match pos */
 356     I32 *scream_pos;            /* Internal iterator of scream. */
 357 } re_scream_pos_data;
 358
 359 /* .what is a character array with one character for each member of .data
 360  * The character describes the function of the corresponding .data item:
 361  *   f - start-class data for regstclass optimization
 362  *   n - Root of op tree for (?{EVAL}) item
 363  *   o - Start op for (?{EVAL}) item
 364  *   p - Pad for (?{EVAL} item
 365  *   s - swash for unicode-style character class, and the multicharacter
 366  *       strings resulting from casefolding the single-character entries
 367  *       in the character class
 368  * 20010712 mjd@plover.com
 369  * (Remember to update re_dup() and pregfree() if you add any items.)
 370  */
 371 struct reg_data {
 372     U32 count;
 373     U8 *what;
 374     void* data[1];
 375 };
 376
 377 struct reg_substr_datum {
 378     I32 min_offset;
 379     I32 max_offset;
 380     SV *substr;         /* non-utf8 variant */
 381     SV *utf8_substr;    /* utf8 variant */
 382 };
 383
 384 struct reg_substr_data {
 385     struct reg_substr_datum data[3];    /* Actual array */
 386 };
 387
 388 #define anchored_substr substrs->data[0].substr
 389 #define anchored_utf8 substrs->data[0].utf8_substr
 390 #define anchored_offset substrs->data[0].min_offset
 391 #define float_substr substrs->data[1].substr
 392 #define float_utf8 substrs->data[1].utf8_substr
 393 #define float_min_offset substrs->data[1].min_offset
 394 #define float_max_offset substrs->data[1].max_offset
 395 #define check_substr substrs->data[2].substr
 396 #define check_utf8 substrs->data[2].utf8_substr
 397 #define check_offset_min substrs->data[2].min_offset
 398 #define check_offset_max substrs->data[2].max_offset