5 * One Ring to rule them all, One Ring to find them
7 * [p.v of _The Lord of the Rings_, opening poem]
8 * [p.50 of _The Lord of the Rings_, I/iii: "The Shadow of the Past"]
9 * [p.254 of _The Lord of the Rings_, II/ii: "The Council of Elrond"]
12 /* This file contains functions for executing a regular expression. See
13 * also regcomp.c which funnily enough, contains functions for compiling
14 * a regular expression.
16 * This file is also copied at build time to ext/re/re_exec.c, where
17 * it's built with -DPERL_EXT_RE_BUILD -DPERL_EXT_RE_DEBUG -DPERL_EXT.
18 * This causes the main functions to be compiled under new names and with
19 * debugging support added, which makes "use re 'debug'" work.
22 /* NOTE: this is derived from Henry Spencer's regexp code, and should not
23 * confused with the original package (see point 3 below). Thanks, Henry!
26 /* Additional note: this code is very heavily munged from Henry's version
27 * in places. In some spots I've traded clarity for efficiency, so don't
28 * blame Henry for some of the lack of readability.
31 /* The names of the functions have been changed from regcomp and
32 * regexec to pregcomp and pregexec in order to avoid conflicts
33 * with the POSIX routines of the same names.
36 #ifdef PERL_EXT_RE_BUILD
41 * pregcomp and pregexec -- regsub and regerror are not used in perl
43 * Copyright (c) 1986 by University of Toronto.
44 * Written by Henry Spencer. Not derived from licensed software.
46 * Permission is granted to anyone to use this software for any
47 * purpose on any computer system, and to redistribute it freely,
48 * subject to the following restrictions:
50 * 1. The author is not responsible for the consequences of use of
51 * this software, no matter how awful, even if they arise
54 * 2. The origin of this software must not be misrepresented, either
55 * by explicit claim or by omission.
57 * 3. Altered versions must be plainly marked as such, and must not
58 * be misrepresented as being the original software.
60 **** Alterations to Henry's code are...
62 **** Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
63 **** 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008
64 **** by Larry Wall and others
66 **** You may distribute under the terms of either the GNU General Public
67 **** License or the Artistic License, as specified in the README file.
69 * Beware that some of this code is subtly aware of the way operator
70 * precedence is structured in regular expressions. Serious changes in
71 * regular-expression syntax might require a total rethink.
74 #define PERL_IN_REGEXEC_C
77 #ifdef PERL_IN_XSUB_RE
83 #include "inline_invlist.c"
84 #include "unicode_constants.h"
87 /* At least one required character in the target string is expressible only in
89 static const char* const non_utf8_target_but_utf8_required
90 = "Can't match, because target string needs to be in UTF-8\n";
93 #define NON_UTF8_TARGET_BUT_UTF8_REQUIRED(target) STMT_START { \
94 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log, "%s", non_utf8_target_but_utf8_required));\
98 #define HAS_NONLATIN1_FOLD_CLOSURE(i) _HAS_NONLATIN1_FOLD_CLOSURE_ONLY_FOR_USE_BY_REGCOMP_DOT_C_AND_REGEXEC_DOT_C(i)
101 #define STATIC static
104 /* Valid only for non-utf8 strings: avoids the reginclass
105 * call if there are no complications: i.e., if everything matchable is
106 * straight forward in the bitmap */
107 #define REGINCLASS(prog,p,c) (ANYOF_FLAGS(p) ? reginclass(prog,p,c,c+1,0) \
108 : ANYOF_BITMAP_TEST(p,*(c)))
114 #define CHR_SVLEN(sv) (utf8_target ? sv_len_utf8(sv) : SvCUR(sv))
115 #define CHR_DIST(a,b) (reginfo->is_utf8_target ? utf8_distance(a,b) : a - b)
117 #define HOPc(pos,off) \
118 (char *)(reginfo->is_utf8_target \
119 ? reghop3((U8*)pos, off, \
120 (U8*)(off >= 0 ? reginfo->strend : reginfo->strbeg)) \
123 #define HOPBACKc(pos, off) \
124 (char*)(reginfo->is_utf8_target \
125 ? reghopmaybe3((U8*)pos, -off, (U8*)(reginfo->strbeg)) \
126 : (pos - off >= reginfo->strbeg) \
130 #define HOP3(pos,off,lim) (reginfo->is_utf8_target ? reghop3((U8*)(pos), off, (U8*)(lim)) : (U8*)(pos + off))
131 #define HOP3c(pos,off,lim) ((char*)HOP3(pos,off,lim))
133 /* lim must be +ve. Returns NULL on overshoot */
134 #define HOPMAYBE3(pos,off,lim) \
135 (reginfo->is_utf8_target \
136 ? reghopmaybe3((U8*)pos, off, (U8*)(lim)) \
137 : ((U8*)pos + off <= lim) \
141 /* like HOP3, but limits the result to <= lim even for the non-utf8 case.
142 * off must be >=0; args should be vars rather than expressions */
143 #define HOP3lim(pos,off,lim) (reginfo->is_utf8_target \
144 ? reghop3((U8*)(pos), off, (U8*)(lim)) \
145 : (U8*)((pos + off) > lim ? lim : (pos + off)))
147 #define HOP4(pos,off,llim, rlim) (reginfo->is_utf8_target \
148 ? reghop4((U8*)(pos), off, (U8*)(llim), (U8*)(rlim)) \
150 #define HOP4c(pos,off,llim, rlim) ((char*)HOP4(pos,off,llim, rlim))
152 #define NEXTCHR_EOS -10 /* nextchr has fallen off the end */
153 #define NEXTCHR_IS_EOS (nextchr < 0)
155 #define SET_nextchr \
156 nextchr = ((locinput < reginfo->strend) ? UCHARAT(locinput) : NEXTCHR_EOS)
158 #define SET_locinput(p) \
163 #define LOAD_UTF8_CHARCLASS(swash_ptr, property_name, invlist) STMT_START { \
165 U8 flags = _CORE_SWASH_INIT_ACCEPT_INVLIST; \
166 swash_ptr = _core_swash_init("utf8", property_name, &PL_sv_undef, \
167 1, 0, invlist, &flags); \
172 /* If in debug mode, we test that a known character properly matches */
174 # define LOAD_UTF8_CHARCLASS_DEBUG_TEST(swash_ptr, \
177 utf8_char_in_property) \
178 LOAD_UTF8_CHARCLASS(swash_ptr, property_name, invlist); \
179 assert(swash_fetch(swash_ptr, (U8 *) utf8_char_in_property, TRUE));
181 # define LOAD_UTF8_CHARCLASS_DEBUG_TEST(swash_ptr, \
184 utf8_char_in_property) \
185 LOAD_UTF8_CHARCLASS(swash_ptr, property_name, invlist)
188 #define LOAD_UTF8_CHARCLASS_ALNUM() LOAD_UTF8_CHARCLASS_DEBUG_TEST( \
189 PL_utf8_swash_ptrs[_CC_WORDCHAR], \
191 PL_XPosix_ptrs[_CC_WORDCHAR], \
192 LATIN_CAPITAL_LETTER_SHARP_S_UTF8);
194 #define LOAD_UTF8_CHARCLASS_GCB() /* Grapheme cluster boundaries */ \
196 LOAD_UTF8_CHARCLASS_DEBUG_TEST(PL_utf8_X_regular_begin, \
197 "_X_regular_begin", \
199 LATIN_CAPITAL_LETTER_SHARP_S_UTF8); \
200 LOAD_UTF8_CHARCLASS_DEBUG_TEST(PL_utf8_X_extend, \
203 COMBINING_GRAVE_ACCENT_UTF8); \
206 #define PLACEHOLDER /* Something for the preprocessor to grab onto */
207 /* TODO: Combine JUMPABLE and HAS_TEXT to cache OP(rn) */
209 /* for use after a quantifier and before an EXACT-like node -- japhy */
210 /* it would be nice to rework regcomp.sym to generate this stuff. sigh
212 * NOTE that *nothing* that affects backtracking should be in here, specifically
213 * VERBS must NOT be included. JUMPABLE is used to determine if we can ignore a
214 * node that is in between two EXACT like nodes when ascertaining what the required
215 * "follow" character is. This should probably be moved to regex compile time
216 * although it may be done at run time beause of the REF possibility - more
217 * investigation required. -- demerphq
219 #define JUMPABLE(rn) ( \
221 (OP(rn) == CLOSE && (!cur_eval || cur_eval->u.eval.close_paren != ARG(rn))) || \
223 OP(rn) == SUSPEND || OP(rn) == IFMATCH || \
224 OP(rn) == PLUS || OP(rn) == MINMOD || \
226 (PL_regkind[OP(rn)] == CURLY && ARG1(rn) > 0) \
228 #define IS_EXACT(rn) (PL_regkind[OP(rn)] == EXACT)
230 #define HAS_TEXT(rn) ( IS_EXACT(rn) || PL_regkind[OP(rn)] == REF )
233 /* Currently these are only used when PL_regkind[OP(rn)] == EXACT so
234 we don't need this definition. */
235 #define IS_TEXT(rn) ( OP(rn)==EXACT || OP(rn)==REF || OP(rn)==NREF )
236 #define IS_TEXTF(rn) ( OP(rn)==EXACTFU || OP(rn)==EXACTFU_SS || OP(rn)==EXACTFA || OP(rn)==EXACTFA_NO_TRIE || OP(rn)==EXACTF || OP(rn)==REFF || OP(rn)==NREFF )
237 #define IS_TEXTFL(rn) ( OP(rn)==EXACTFL || OP(rn)==REFFL || OP(rn)==NREFFL )
240 /* ... so we use this as its faster. */
241 #define IS_TEXT(rn) ( OP(rn)==EXACT )
242 #define IS_TEXTFU(rn) ( OP(rn)==EXACTFU || OP(rn)==EXACTFU_SS || OP(rn) == EXACTFA || OP(rn) == EXACTFA_NO_TRIE)
243 #define IS_TEXTF(rn) ( OP(rn)==EXACTF )
244 #define IS_TEXTFL(rn) ( OP(rn)==EXACTFL )
249 Search for mandatory following text node; for lookahead, the text must
250 follow but for lookbehind (rn->flags != 0) we skip to the next step.
252 #define FIND_NEXT_IMPT(rn) STMT_START { \
253 while (JUMPABLE(rn)) { \
254 const OPCODE type = OP(rn); \
255 if (type == SUSPEND || PL_regkind[type] == CURLY) \
256 rn = NEXTOPER(NEXTOPER(rn)); \
257 else if (type == PLUS) \
259 else if (type == IFMATCH) \
260 rn = (rn->flags == 0) ? NEXTOPER(NEXTOPER(rn)) : rn + ARG(rn); \
261 else rn += NEXT_OFF(rn); \
265 /* These constants are for finding GCB=LV and GCB=LVT in the CLUMP regnode.
266 * These are for the pre-composed Hangul syllables, which are all in a
267 * contiguous block and arranged there in such a way so as to facilitate
268 * alorithmic determination of their characteristics. As such, they don't need
269 * a swash, but can be determined by simple arithmetic. Almost all are
270 * GCB=LVT, but every 28th one is a GCB=LV */
271 #define SBASE 0xAC00 /* Start of block */
272 #define SCount 11172 /* Length of block */
275 #define SLAB_FIRST(s) (&(s)->states[0])
276 #define SLAB_LAST(s) (&(s)->states[PERL_REGMATCH_SLAB_SLOTS-1])
278 static void S_setup_eval_state(pTHX_ regmatch_info *const reginfo);
279 static void S_cleanup_regmatch_info_aux(pTHX_ void *arg);
280 static regmatch_state * S_push_slab(pTHX);
282 #define REGCP_PAREN_ELEMS 3
283 #define REGCP_OTHER_ELEMS 3
284 #define REGCP_FRAME_ELEMS 1
285 /* REGCP_FRAME_ELEMS are not part of the REGCP_OTHER_ELEMS and
286 * are needed for the regexp context stack bookkeeping. */
289 S_regcppush(pTHX_ const regexp *rex, I32 parenfloor, U32 maxopenparen)
291 const int retval = PL_savestack_ix;
292 const int paren_elems_to_push =
293 (maxopenparen - parenfloor) * REGCP_PAREN_ELEMS;
294 const UV total_elems = paren_elems_to_push + REGCP_OTHER_ELEMS;
295 const UV elems_shifted = total_elems << SAVE_TIGHT_SHIFT;
297 GET_RE_DEBUG_FLAGS_DECL;
299 PERL_ARGS_ASSERT_REGCPPUSH;
301 if (paren_elems_to_push < 0)
302 Perl_croak(aTHX_ "panic: paren_elems_to_push, %i < 0, maxopenparen: %i parenfloor: %i REGCP_PAREN_ELEMS: %u",
303 (int)paren_elems_to_push, (int)maxopenparen,
304 (int)parenfloor, (unsigned)REGCP_PAREN_ELEMS);
306 if ((elems_shifted >> SAVE_TIGHT_SHIFT) != total_elems)
307 Perl_croak(aTHX_ "panic: paren_elems_to_push offset %"UVuf
308 " out of range (%lu-%ld)",
310 (unsigned long)maxopenparen,
313 SSGROW(total_elems + REGCP_FRAME_ELEMS);
316 if ((int)maxopenparen > (int)parenfloor)
317 PerlIO_printf(Perl_debug_log,
318 "rex=0x%"UVxf" offs=0x%"UVxf": saving capture indices:\n",
323 for (p = parenfloor+1; p <= (I32)maxopenparen; p++) {
324 /* REGCP_PARENS_ELEMS are pushed per pairs of parentheses. */
325 SSPUSHIV(rex->offs[p].end);
326 SSPUSHIV(rex->offs[p].start);
327 SSPUSHINT(rex->offs[p].start_tmp);
328 DEBUG_BUFFERS_r(PerlIO_printf(Perl_debug_log,
329 " \\%"UVuf": %"IVdf"(%"IVdf")..%"IVdf"\n",
331 (IV)rex->offs[p].start,
332 (IV)rex->offs[p].start_tmp,
336 /* REGCP_OTHER_ELEMS are pushed in any case, parentheses or no. */
337 SSPUSHINT(maxopenparen);
338 SSPUSHINT(rex->lastparen);
339 SSPUSHINT(rex->lastcloseparen);
340 SSPUSHUV(SAVEt_REGCONTEXT | elems_shifted); /* Magic cookie. */
345 /* These are needed since we do not localize EVAL nodes: */
346 #define REGCP_SET(cp) \
348 PerlIO_printf(Perl_debug_log, \
349 " Setting an EVAL scope, savestack=%"IVdf"\n", \
350 (IV)PL_savestack_ix)); \
353 #define REGCP_UNWIND(cp) \
355 if (cp != PL_savestack_ix) \
356 PerlIO_printf(Perl_debug_log, \
357 " Clearing an EVAL scope, savestack=%"IVdf"..%"IVdf"\n", \
358 (IV)(cp), (IV)PL_savestack_ix)); \
361 #define UNWIND_PAREN(lp, lcp) \
362 for (n = rex->lastparen; n > lp; n--) \
363 rex->offs[n].end = -1; \
364 rex->lastparen = n; \
365 rex->lastcloseparen = lcp;
369 S_regcppop(pTHX_ regexp *rex, U32 *maxopenparen_p)
373 GET_RE_DEBUG_FLAGS_DECL;
375 PERL_ARGS_ASSERT_REGCPPOP;
377 /* Pop REGCP_OTHER_ELEMS before the parentheses loop starts. */
379 assert((i & SAVE_MASK) == SAVEt_REGCONTEXT); /* Check that the magic cookie is there. */
380 i >>= SAVE_TIGHT_SHIFT; /* Parentheses elements to pop. */
381 rex->lastcloseparen = SSPOPINT;
382 rex->lastparen = SSPOPINT;
383 *maxopenparen_p = SSPOPINT;
385 i -= REGCP_OTHER_ELEMS;
386 /* Now restore the parentheses context. */
388 if (i || rex->lastparen + 1 <= rex->nparens)
389 PerlIO_printf(Perl_debug_log,
390 "rex=0x%"UVxf" offs=0x%"UVxf": restoring capture indices to:\n",
395 paren = *maxopenparen_p;
396 for ( ; i > 0; i -= REGCP_PAREN_ELEMS) {
398 rex->offs[paren].start_tmp = SSPOPINT;
399 rex->offs[paren].start = SSPOPIV;
401 if (paren <= rex->lastparen)
402 rex->offs[paren].end = tmps;
403 DEBUG_BUFFERS_r( PerlIO_printf(Perl_debug_log,
404 " \\%"UVuf": %"IVdf"(%"IVdf")..%"IVdf"%s\n",
406 (IV)rex->offs[paren].start,
407 (IV)rex->offs[paren].start_tmp,
408 (IV)rex->offs[paren].end,
409 (paren > rex->lastparen ? "(skipped)" : ""));
414 /* It would seem that the similar code in regtry()
415 * already takes care of this, and in fact it is in
416 * a better location to since this code can #if 0-ed out
417 * but the code in regtry() is needed or otherwise tests
418 * requiring null fields (pat.t#187 and split.t#{13,14}
419 * (as of patchlevel 7877) will fail. Then again,
420 * this code seems to be necessary or otherwise
421 * this erroneously leaves $1 defined: "1" =~ /^(?:(\d)x)?\d$/
422 * --jhi updated by dapm */
423 for (i = rex->lastparen + 1; i <= rex->nparens; i++) {
424 if (i > *maxopenparen_p)
425 rex->offs[i].start = -1;
426 rex->offs[i].end = -1;
427 DEBUG_BUFFERS_r( PerlIO_printf(Perl_debug_log,
428 " \\%"UVuf": %s ..-1 undeffing\n",
430 (i > *maxopenparen_p) ? "-1" : " "
436 /* restore the parens and associated vars at savestack position ix,
437 * but without popping the stack */
440 S_regcp_restore(pTHX_ regexp *rex, I32 ix, U32 *maxopenparen_p)
442 I32 tmpix = PL_savestack_ix;
443 PL_savestack_ix = ix;
444 regcppop(rex, maxopenparen_p);
445 PL_savestack_ix = tmpix;
448 #define regcpblow(cp) LEAVE_SCOPE(cp) /* Ignores regcppush()ed data. */
451 S_isFOO_lc(pTHX_ const U8 classnum, const U8 character)
453 /* Returns a boolean as to whether or not 'character' is a member of the
454 * Posix character class given by 'classnum' that should be equivalent to a
455 * value in the typedef '_char_class_number'.
457 * Ideally this could be replaced by a just an array of function pointers
458 * to the C library functions that implement the macros this calls.
459 * However, to compile, the precise function signatures are required, and
460 * these may vary from platform to to platform. To avoid having to figure
461 * out what those all are on each platform, I (khw) am using this method,
462 * which adds an extra layer of function call overhead (unless the C
463 * optimizer strips it away). But we don't particularly care about
464 * performance with locales anyway. */
466 switch ((_char_class_number) classnum) {
467 case _CC_ENUM_ALPHANUMERIC: return isALPHANUMERIC_LC(character);
468 case _CC_ENUM_ALPHA: return isALPHA_LC(character);
469 case _CC_ENUM_ASCII: return isASCII_LC(character);
470 case _CC_ENUM_BLANK: return isBLANK_LC(character);
471 case _CC_ENUM_CASED: return isLOWER_LC(character)
472 || isUPPER_LC(character);
473 case _CC_ENUM_CNTRL: return isCNTRL_LC(character);
474 case _CC_ENUM_DIGIT: return isDIGIT_LC(character);
475 case _CC_ENUM_GRAPH: return isGRAPH_LC(character);
476 case _CC_ENUM_LOWER: return isLOWER_LC(character);
477 case _CC_ENUM_PRINT: return isPRINT_LC(character);
478 case _CC_ENUM_PSXSPC: return isPSXSPC_LC(character);
479 case _CC_ENUM_PUNCT: return isPUNCT_LC(character);
480 case _CC_ENUM_SPACE: return isSPACE_LC(character);
481 case _CC_ENUM_UPPER: return isUPPER_LC(character);
482 case _CC_ENUM_WORDCHAR: return isWORDCHAR_LC(character);
483 case _CC_ENUM_XDIGIT: return isXDIGIT_LC(character);
484 default: /* VERTSPACE should never occur in locales */
485 Perl_croak(aTHX_ "panic: isFOO_lc() has an unexpected character class '%d'", classnum);
488 assert(0); /* NOTREACHED */
493 S_isFOO_utf8_lc(pTHX_ const U8 classnum, const U8* character)
495 /* Returns a boolean as to whether or not the (well-formed) UTF-8-encoded
496 * 'character' is a member of the Posix character class given by 'classnum'
497 * that should be equivalent to a value in the typedef
498 * '_char_class_number'.
500 * This just calls isFOO_lc on the code point for the character if it is in
501 * the range 0-255. Outside that range, all characters avoid Unicode
502 * rules, ignoring any locale. So use the Unicode function if this class
503 * requires a swash, and use the Unicode macro otherwise. */
505 PERL_ARGS_ASSERT_ISFOO_UTF8_LC;
507 if (UTF8_IS_INVARIANT(*character)) {
508 return isFOO_lc(classnum, *character);
510 else if (UTF8_IS_DOWNGRADEABLE_START(*character)) {
511 return isFOO_lc(classnum,
512 TWO_BYTE_UTF8_TO_NATIVE(*character, *(character + 1)));
515 if (classnum < _FIRST_NON_SWASH_CC) {
517 /* Initialize the swash unless done already */
518 if (! PL_utf8_swash_ptrs[classnum]) {
519 U8 flags = _CORE_SWASH_INIT_ACCEPT_INVLIST;
520 PL_utf8_swash_ptrs[classnum] =
521 _core_swash_init("utf8",
524 PL_XPosix_ptrs[classnum], &flags);
527 return cBOOL(swash_fetch(PL_utf8_swash_ptrs[classnum], (U8 *)
529 TRUE /* is UTF */ ));
532 switch ((_char_class_number) classnum) {
534 case _CC_ENUM_PSXSPC: return is_XPERLSPACE_high(character);
536 case _CC_ENUM_BLANK: return is_HORIZWS_high(character);
537 case _CC_ENUM_XDIGIT: return is_XDIGIT_high(character);
538 case _CC_ENUM_VERTSPACE: return is_VERTWS_high(character);
539 default: return 0; /* Things like CNTRL are always
543 assert(0); /* NOTREACHED */
548 * pregexec and friends
551 #ifndef PERL_IN_XSUB_RE
553 - pregexec - match a regexp against a string
556 Perl_pregexec(pTHX_ REGEXP * const prog, char* stringarg, char *strend,
557 char *strbeg, SSize_t minend, SV *screamer, U32 nosave)
558 /* stringarg: the point in the string at which to begin matching */
559 /* strend: pointer to null at end of string */
560 /* strbeg: real beginning of string */
561 /* minend: end of match must be >= minend bytes after stringarg. */
562 /* screamer: SV being matched: only used for utf8 flag, pos() etc; string
563 * itself is accessed via the pointers above */
564 /* nosave: For optimizations. */
566 PERL_ARGS_ASSERT_PREGEXEC;
569 regexec_flags(prog, stringarg, strend, strbeg, minend, screamer, NULL,
570 nosave ? 0 : REXEC_COPY_STR);
576 /* re_intuit_start():
578 * Based on some optimiser hints, try to find the earliest position in the
579 * string where the regex could match.
581 * rx: the regex to match against
582 * sv: the SV being matched: only used for utf8 flag; the string
583 * itself is accessed via the pointers below. Note that on
584 * something like an overloaded SV, SvPOK(sv) may be false
585 * and the string pointers may point to something unrelated to
587 * strbeg: real beginning of string
588 * strpos: the point in the string at which to begin matching
589 * strend: pointer to the byte following the last char of the string
590 * flags currently unused; set to 0
591 * data: currently unused; set to NULL
593 * The basic idea of re_intuit_start() is to use some known information
594 * about the pattern, namely:
596 * a) the longest known anchored substring (i.e. one that's at a
597 * constant offset from the beginning of the pattern; but not
598 * necessarily at a fixed offset from the beginning of the
600 * b) the longest floating substring (i.e. one that's not at a constant
601 * offset from the beginning of the pattern);
602 * c) Whether the pattern is anchored to the string; either
603 * an absolute anchor: /^../, or anchored to \n: /^.../m,
604 * or anchored to pos(): /\G/;
605 * d) A start class: a real or synthetic character class which
606 * represents which characters are legal at the start of the pattern;
608 * to either quickly reject the match, or to find the earliest position
609 * within the string at which the pattern might match, thus avoiding
610 * running the full NFA engine at those earlier locations, only to
611 * eventually fail and retry further along.
613 * Returns NULL if the pattern can't match, or returns the address within
614 * the string which is the earliest place the match could occur.
616 * The longest of the anchored and floating substrings is called 'check'
617 * and is checked first. The other is called 'other' and is checked
618 * second. The 'other' substring may not be present. For example,
620 * /(abc|xyz)ABC\d{0,3}DEFG/
624 * check substr (float) = "DEFG", offset 6..9 chars
625 * other substr (anchored) = "ABC", offset 3..3 chars
628 * Be aware that during the course of this function, sometimes 'anchored'
629 * refers to a substring being anchored relative to the start of the
630 * pattern, and sometimes to the pattern itself being anchored relative to
631 * the string. For example:
633 * /\dabc/: "abc" is anchored to the pattern;
634 * /^\dabc/: "abc" is anchored to the pattern and the string;
635 * /\d+abc/: "abc" is anchored to neither the pattern nor the string;
636 * /^\d+abc/: "abc" is anchored to neither the pattern nor the string,
637 * but the pattern is anchored to the string.
641 Perl_re_intuit_start(pTHX_
644 const char * const strbeg,
648 re_scream_pos_data *data)
650 struct regexp *const prog = ReANY(rx);
651 SSize_t start_shift = prog->check_offset_min;
652 /* Should be nonnegative! */
653 SSize_t end_shift = 0;
654 /* current lowest pos in string where the regex can start matching */
655 char *rx_origin = strpos;
657 const bool utf8_target = (sv && SvUTF8(sv)) ? 1 : 0; /* if no sv we have to assume bytes */
658 U8 other_ix = 1 - prog->substrs->check_ix;
660 char *other_last = strpos;/* latest pos 'other' substr already checked to */
661 char *check_at = NULL; /* check substr found at this pos */
662 const I32 multiline = prog->extflags & RXf_PMf_MULTILINE;
663 RXi_GET_DECL(prog,progi);
664 regmatch_info reginfo_buf; /* create some info to pass to find_byclass */
665 regmatch_info *const reginfo = ®info_buf;
666 GET_RE_DEBUG_FLAGS_DECL;
668 PERL_ARGS_ASSERT_RE_INTUIT_START;
669 PERL_UNUSED_ARG(flags);
670 PERL_UNUSED_ARG(data);
672 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
673 "Intuit: trying to determine minimum start position...\n"));
675 /* for now, assume that all substr offsets are positive. If at some point
676 * in the future someone wants to do clever things with look-behind and
677 * -ve offsets, they'll need to fix up any code in this function
678 * which uses these offsets. See the thread beginning
679 * <20140113145929.GF27210@iabyn.com>
681 assert(prog->substrs->data[0].min_offset >= 0);
682 assert(prog->substrs->data[0].max_offset >= 0);
683 assert(prog->substrs->data[1].min_offset >= 0);
684 assert(prog->substrs->data[1].max_offset >= 0);
685 assert(prog->substrs->data[2].min_offset >= 0);
686 assert(prog->substrs->data[2].max_offset >= 0);
688 /* for now, assume that if both present, that the floating substring
689 * doesn't start before the anchored substring.
690 * If you break this assumption (e.g. doing better optimisations
691 * with lookahead/behind), then you'll need to audit the code in this
692 * function carefully first
695 ! ( (prog->anchored_utf8 || prog->anchored_substr)
696 && (prog->float_utf8 || prog->float_substr))
697 || (prog->float_min_offset >= prog->anchored_offset));
699 /* byte rather than char calculation for efficiency. It fails
700 * to quickly reject some cases that can't match, but will reject
701 * them later after doing full char arithmetic */
702 if (prog->minlen > strend - strpos) {
703 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
704 " String too short...\n"));
708 reginfo->is_utf8_target = cBOOL(utf8_target);
709 reginfo->info_aux = NULL;
710 reginfo->strbeg = strbeg;
711 reginfo->strend = strend;
712 reginfo->is_utf8_pat = cBOOL(RX_UTF8(rx));
714 /* not actually used within intuit, but zero for safety anyway */
715 reginfo->poscache_maxiter = 0;
718 if (!prog->check_utf8 && prog->check_substr)
719 to_utf8_substr(prog);
720 check = prog->check_utf8;
722 if (!prog->check_substr && prog->check_utf8) {
723 if (! to_byte_substr(prog)) {
724 NON_UTF8_TARGET_BUT_UTF8_REQUIRED(fail);
727 check = prog->check_substr;
730 /* dump the various substring data */
731 DEBUG_OPTIMISE_MORE_r({
733 for (i=0; i<=2; i++) {
734 SV *sv = (utf8_target ? prog->substrs->data[i].utf8_substr
735 : prog->substrs->data[i].substr);
739 PerlIO_printf(Perl_debug_log,
740 " substrs[%d]: min=%"IVdf" max=%"IVdf" end shift=%"IVdf
741 " useful=%"IVdf" utf8=%d [%s]\n",
743 (IV)prog->substrs->data[i].min_offset,
744 (IV)prog->substrs->data[i].max_offset,
745 (IV)prog->substrs->data[i].end_shift,
752 if (prog->intflags & PREGf_ANCH) { /* Match at \G, beg-of-str or after \n */
754 /* ml_anch: check after \n?
756 * A note about IMPLICIT: on an un-anchored pattern beginning
757 * with /.*.../, these flags will have been added by the
759 * /.*abc/, /.*abc/m: PREGf_IMPLICIT | PREGf_ANCH_MBOL
760 * /.*abc/s: PREGf_IMPLICIT | PREGf_ANCH_SBOL
762 ml_anch = (prog->intflags & PREGf_ANCH_MBOL)
763 && !(prog->intflags & PREGf_IMPLICIT);
765 if (!ml_anch && !(prog->intflags & PREGf_IMPLICIT)) {
766 /* we are only allowed to match at BOS or \G */
768 /* trivially reject if there's a BOS anchor and we're not at BOS.
770 * Note that we don't try to do a similar quick reject for
771 * \G, since generally the caller will have calculated strpos
772 * based on pos() and gofs, so the string is already correctly
773 * anchored by definition; and handling the exceptions would
774 * be too fiddly (e.g. REXEC_IGNOREPOS).
776 if ( strpos != strbeg
777 && (prog->intflags & (PREGf_ANCH_BOL|PREGf_ANCH_SBOL)))
779 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
780 " Not at start...\n"));
784 /* in the presence of an anchor, the anchored (relative to the
785 * start of the regex) substr must also be anchored relative
786 * to strpos. So quickly reject if substr isn't found there.
787 * This works for \G too, because the caller will already have
788 * subtracted gofs from pos, and gofs is the offset from the
789 * \G to the start of the regex. For example, in /.abc\Gdef/,
790 * where substr="abcdef", pos()=3, gofs=4, offset_min=1:
791 * caller will have set strpos=pos()-4; we look for the substr
792 * at position pos()-4+1, which lines up with the "a" */
794 if (prog->check_offset_min == prog->check_offset_max
795 && !(prog->intflags & PREGf_CANY_SEEN))
797 /* Substring at constant offset from beg-of-str... */
798 SSize_t slen = SvCUR(check);
799 char *s = HOP3c(strpos, prog->check_offset_min, strend);
801 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
802 " Looking for check substr at fixed offset %"IVdf"...\n",
803 (IV)prog->check_offset_min));
806 /* In this case, the regex is anchored at the end too.
807 * Unless it's a multiline match, the lengths must match
808 * exactly, give or take a \n. NB: slen >= 1 since
809 * the last char of check is \n */
811 && ( strend - s > slen
812 || strend - s < slen - 1
813 || (strend - s == slen && strend[-1] != '\n')))
815 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
816 " String too long...\n"));
819 /* Now should match s[0..slen-2] */
822 if (slen && (*SvPVX_const(check) != *s
823 || (slen > 1 && memNE(SvPVX_const(check), s, slen))))
825 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
826 " String not equal...\n"));
831 goto success_at_start;
836 end_shift = prog->check_end_shift;
838 #ifdef DEBUGGING /* 7/99: reports of failure (with the older version) */
840 Perl_croak(aTHX_ "panic: end_shift: %"IVdf" pattern:\n%s\n ",
841 (IV)end_shift, RX_PRECOMP(prog));
846 /* This is the (re)entry point of the main loop in this function.
847 * The goal of this loop is to:
848 * 1) find the "check" substring in the region rx_origin..strend
849 * (adjusted by start_shift / end_shift). If not found, reject
851 * 2) If it exists, look for the "other" substr too if defined; for
852 * example, if the check substr maps to the anchored substr, then
853 * check the floating substr, and vice-versa. If not found, go
854 * back to (1) with rx_origin suitably incremented.
855 * 3) If we find an rx_origin position that doesn't contradict
856 * either of the substrings, then check the possible additional
857 * constraints on rx_origin of /^.../m or a known start class.
858 * If these fail, then depending on which constraints fail, jump
859 * back to here, or to various other re-entry points further along
860 * that skip some of the first steps.
861 * 4) If we pass all those tests, update the BmUSEFUL() count on the
862 * substring. If the start position was determined to be at the
863 * beginning of the string - so, not rejected, but not optimised,
864 * since we have to run regmatch from position 0 - decrement the
865 * BmUSEFUL() count. Otherwise increment it.
869 /* first, look for the 'check' substring */
875 DEBUG_OPTIMISE_MORE_r({
876 PerlIO_printf(Perl_debug_log,
877 " At restart: rx_origin=%"IVdf" Check offset min: %"IVdf
878 " Start shift: %"IVdf" End shift %"IVdf
879 " Real end Shift: %"IVdf"\n",
880 (IV)(rx_origin - strpos),
881 (IV)prog->check_offset_min,
884 (IV)prog->check_end_shift);
887 if (prog->intflags & PREGf_CANY_SEEN) {
888 start_point= (U8*)(rx_origin + start_shift);
889 end_point= (U8*)(strend - end_shift);
890 if (start_point > end_point)
893 end_point = HOP3(strend, -end_shift, strbeg);
894 start_point = HOPMAYBE3(rx_origin, start_shift, end_point);
900 /* If the regex is absolutely anchored to either the start of the
901 * string (BOL,SBOL) or to pos() (ANCH_GPOS), then
902 * check_offset_max represents an upper bound on the string where
903 * the substr could start. For the ANCH_GPOS case, we assume that
904 * the caller of intuit will have already set strpos to
905 * pos()-gofs, so in this case strpos + offset_max will still be
906 * an upper bound on the substr.
909 && prog->intflags & PREGf_ANCH
910 && prog->check_offset_max != SSize_t_MAX)
912 SSize_t len = SvCUR(check) - !!SvTAIL(check);
913 const char * const anchor =
914 (prog->intflags & PREGf_ANCH_GPOS ? strpos : strbeg);
916 /* do a bytes rather than chars comparison. It's conservative;
917 * so it skips doing the HOP if the result can't possibly end
918 * up earlier than the old value of end_point.
920 if ((char*)end_point - anchor > prog->check_offset_max) {
921 end_point = HOP3lim((U8*)anchor,
922 prog->check_offset_max,
928 DEBUG_OPTIMISE_MORE_r({
929 PerlIO_printf(Perl_debug_log, " fbm_instr len=%d str=<%.*s>\n",
930 (int)(end_point - start_point),
931 (int)(end_point - start_point) > 20 ? 20 : (int)(end_point - start_point),
935 check_at = fbm_instr( start_point, end_point,
936 check, multiline ? FBMrf_MULTILINE : 0);
938 /* Update the count-of-usability, remove useless subpatterns,
942 RE_PV_QUOTED_DECL(quoted, utf8_target, PERL_DEBUG_PAD_ZERO(0),
943 SvPVX_const(check), RE_SV_DUMPLEN(check), 30);
944 PerlIO_printf(Perl_debug_log, " %s %s substr %s%s%s",
945 (check_at ? "Found" : "Did not find"),
946 (check == (utf8_target ? prog->anchored_utf8 : prog->anchored_substr)
947 ? "anchored" : "floating"),
950 (check_at ? " at offset " : "...\n") );
955 /* Finish the diagnostic message */
956 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log, "%ld...\n", (long)(check_at - strpos)) );
958 /* set rx_origin to the minimum position where the regex could start
959 * matching, given the constraint of the just-matched check substring.
960 * But don't set it lower than previously.
963 if (check_at - rx_origin > prog->check_offset_max)
964 rx_origin = HOP3c(check_at, -prog->check_offset_max, rx_origin);
968 /* now look for the 'other' substring if defined */
970 if (utf8_target ? prog->substrs->data[other_ix].utf8_substr
971 : prog->substrs->data[other_ix].substr)
973 /* Take into account the "other" substring. */
977 struct reg_substr_datum *other;
980 other = &prog->substrs->data[other_ix];
982 /* if "other" is anchored:
983 * we've previously found a floating substr starting at check_at.
984 * This means that the regex origin must lie somewhere
985 * between min (rx_origin): HOP3(check_at, -check_offset_max)
986 * and max: HOP3(check_at, -check_offset_min)
987 * (except that min will be >= strpos)
988 * So the fixed substr must lie somewhere between
989 * HOP3(min, anchored_offset)
990 * HOP3(max, anchored_offset) + SvCUR(substr)
993 /* if "other" is floating
994 * Calculate last1, the absolute latest point where the
995 * floating substr could start in the string, ignoring any
996 * constraints from the earlier fixed match. It is calculated
999 * strend - prog->minlen (in chars) is the absolute latest
1000 * position within the string where the origin of the regex
1001 * could appear. The latest start point for the floating
1002 * substr is float_min_offset(*) on from the start of the
1003 * regex. last1 simply combines thee two offsets.
1005 * (*) You might think the latest start point should be
1006 * float_max_offset from the regex origin, and technically
1007 * you'd be correct. However, consider
1009 * Here, float min, max are 3,5 and minlen is 7.
1010 * This can match either
1014 * In the first case, the regex matches minlen chars; in the
1015 * second, minlen+1, in the third, minlen+2.
1016 * In the first case, the floating offset is 3 (which equals
1017 * float_min), in the second, 4, and in the third, 5 (which
1018 * equals float_max). In all cases, the floating string bcd
1019 * can never start more than 4 chars from the end of the
1020 * string, which equals minlen - float_min. As the substring
1021 * starts to match more than float_min from the start of the
1022 * regex, it makes the regex match more than minlen chars,
1023 * and the two cancel each other out. So we can always use
1024 * float_min - minlen, rather than float_max - minlen for the
1025 * latest position in the string.
1027 * Note that -minlen + float_min_offset is equivalent (AFAIKT)
1028 * to CHR_SVLEN(must) - !!SvTAIL(must) + prog->float_end_shift
1031 assert(prog->minlen >= other->min_offset);
1032 last1 = HOP3c(strend,
1033 other->min_offset - prog->minlen, strbeg);
1035 if (other_ix) {/* i.e. if (other-is-float) */
1036 /* last is the latest point where the floating substr could
1037 * start, *given* any constraints from the earlier fixed
1038 * match. This constraint is that the floating string starts
1039 * <= float_max_offset chars from the regex origin (rx_origin).
1040 * If this value is less than last1, use it instead.
1042 assert(rx_origin <= last1);
1044 /* this condition handles the offset==infinity case, and
1045 * is a short-cut otherwise. Although it's comparing a
1046 * byte offset to a char length, it does so in a safe way,
1047 * since 1 char always occupies 1 or more bytes,
1048 * so if a string range is (last1 - rx_origin) bytes,
1049 * it will be less than or equal to (last1 - rx_origin)
1050 * chars; meaning it errs towards doing the accurate HOP3
1051 * rather than just using last1 as a short-cut */
1052 (last1 - rx_origin) < other->max_offset
1054 : (char*)HOP3lim(rx_origin, other->max_offset, last1);
1057 assert(strpos + start_shift <= check_at);
1058 last = HOP4c(check_at, other->min_offset - start_shift,
1062 s = HOP3c(rx_origin, other->min_offset, strend);
1063 if (s < other_last) /* These positions already checked */
1066 must = utf8_target ? other->utf8_substr : other->substr;
1067 assert(SvPOK(must));
1070 (unsigned char*)last + SvCUR(must) - (SvTAIL(must)!=0),
1072 multiline ? FBMrf_MULTILINE : 0
1075 RE_PV_QUOTED_DECL(quoted, utf8_target, PERL_DEBUG_PAD_ZERO(0),
1076 SvPVX_const(must), RE_SV_DUMPLEN(must), 30);
1077 PerlIO_printf(Perl_debug_log, " %s %s substr %s%s",
1078 s ? "Found" : "Contradicts",
1079 other_ix ? "floating" : "anchored",
1080 quoted, RE_SV_TAIL(must));
1085 /* last1 is latest possible substr location. If we didn't
1086 * find it before there, we never will */
1087 if (last >= last1) {
1088 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
1089 ", giving up...\n"));
1093 /* try to find the check substr again at a later
1094 * position. Maybe next time we'll find the "other" substr
1096 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
1097 ", trying %s at offset %ld...\n",
1098 (other_ix ? "floating" : "anchored"),
1099 (long)(HOP3c(check_at, 1, strend) - strpos)));
1101 other_last = HOP3c(last, 1, strend) /* highest failure */;
1103 other_ix /* i.e. if other-is-float */
1104 ? HOP3c(rx_origin, 1, strend)
1105 : HOP4c(last, 1 - other->min_offset, strbeg, strend);
1109 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log, " at offset %ld...\n",
1110 (long)(s - strpos)));
1112 if (other_ix) { /* if (other-is-float) */
1113 /* other_last is set to s, not s+1, since its possible for
1114 * a floating substr to fail first time, then succeed
1115 * second time at the same floating position; e.g.:
1116 * "-AB--AABZ" =~ /\wAB\d*Z/
1117 * The first time round, anchored and float match at
1118 * "-(AB)--AAB(Z)" then fail on the initial \w character
1119 * class. Second time round, they match at "-AB--A(AB)(Z)".
1124 rx_origin = HOP3c(s, -other->min_offset, strbeg);
1125 other_last = HOP3c(s, 1, strend);
1130 DEBUG_OPTIMISE_MORE_r(
1131 PerlIO_printf(Perl_debug_log,
1132 " Check-only match: offset min:%"IVdf" max:%"IVdf
1133 " check_at:%"IVdf" rx_origin:%"IVdf" rx_origin-check_at:%"IVdf
1134 " strend-strpos:%"IVdf"\n",
1135 (IV)prog->check_offset_min,
1136 (IV)prog->check_offset_max,
1137 (IV)(check_at-strpos),
1138 (IV)(rx_origin-strpos),
1139 (IV)(rx_origin-check_at),
1145 postprocess_substr_matches:
1147 /* handle the extra constraint of /^.../m if present */
1149 if (ml_anch && rx_origin != strbeg && rx_origin[-1] != '\n') {
1152 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
1153 " looking for /^/m anchor"));
1155 /* we have failed the constraint of a \n before rx_origin.
1156 * Find the next \n, if any, even if it's beyond the current
1157 * anchored and/or floating substrings. Whether we should be
1158 * scanning ahead for the next \n or the next substr is debatable.
1159 * On the one hand you'd expect rare substrings to appear less
1160 * often than \n's. On the other hand, searching for \n means
1161 * we're effectively flipping been check_substr and "\n" on each
1162 * iteration as the current "rarest" string candidate, which
1163 * means for example that we'll quickly reject the whole string if
1164 * hasn't got a \n, rather than trying every substr position
1168 s = HOP3c(strend, - prog->minlen, strpos);
1169 if (s <= rx_origin ||
1170 ! ( rx_origin = (char *)memchr(rx_origin, '\n', s - rx_origin)))
1172 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
1173 " Did not find /%s^%s/m...\n",
1174 PL_colors[0], PL_colors[1]));
1178 /* earliest possible origin is 1 char after the \n.
1179 * (since *rx_origin == '\n', it's safe to ++ here rather than
1180 * HOP(rx_origin, 1)) */
1183 if (prog->substrs->check_ix == 0 /* check is anchored */
1184 || rx_origin >= HOP3c(check_at, - prog->check_offset_min, strpos))
1186 /* Position contradicts check-string; either because
1187 * check was anchored (and thus has no wiggle room),
1188 * or check was float and rx_origin is above the float range */
1189 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
1190 " Found /%s^%s/m, restarting lookup for check-string at offset %ld...\n",
1191 PL_colors[0], PL_colors[1], (long)(rx_origin - strpos)));
1195 /* if we get here, the check substr must have been float,
1196 * is in range, and we may or may not have had an anchored
1197 * "other" substr which still contradicts */
1198 assert(prog->substrs->check_ix); /* check is float */
1200 if (utf8_target ? prog->anchored_utf8 : prog->anchored_substr) {
1201 /* whoops, the anchored "other" substr exists, so we still
1202 * contradict. On the other hand, the float "check" substr
1203 * didn't contradict, so just retry the anchored "other"
1205 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
1206 " Found /%s^%s/m at offset %ld, rescanning for anchored from offset %ld...\n",
1207 PL_colors[0], PL_colors[1],
1208 (long)(rx_origin - strpos),
1209 (long)(rx_origin - strpos + prog->anchored_offset)));
1210 goto do_other_substr;
1213 /* success: we don't contradict the found floating substring
1214 * (and there's no anchored substr). */
1215 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
1216 " Found /%s^%s/m at offset %ld...\n",
1217 PL_colors[0], PL_colors[1], (long)(rx_origin - strpos)));
1220 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
1221 " (multiline anchor test skipped)\n"));
1227 /* if we have a starting character class, then test that extra constraint.
1228 * (trie stclasses are too expensive to use here, we are better off to
1229 * leave it to regmatch itself) */
1231 if (progi->regstclass && PL_regkind[OP(progi->regstclass)]!=TRIE) {
1232 const U8* const str = (U8*)STRING(progi->regstclass);
1234 /* XXX this value could be pre-computed */
1235 const int cl_l = (PL_regkind[OP(progi->regstclass)] == EXACT
1236 ? (reginfo->is_utf8_pat
1237 ? utf8_distance(str + STR_LEN(progi->regstclass), str)
1238 : STR_LEN(progi->regstclass))
1242 /* latest pos that a matching float substr constrains rx start to */
1243 char *rx_max_float = NULL;
1245 /* if the current rx_origin is anchored, either by satisfying an
1246 * anchored substring constraint, or a /^.../m constraint, then we
1247 * can reject the current origin if the start class isn't found
1248 * at the current position. If we have a float-only match, then
1249 * rx_origin is constrained to a range; so look for the start class
1250 * in that range. if neither, then look for the start class in the
1251 * whole rest of the string */
1253 /* XXX DAPM it's not clear what the minlen test is for, and why
1254 * it's not used in the floating case. Nothing in the test suite
1255 * causes minlen == 0 here. See <20140313134639.GS12844@iabyn.com>.
1256 * Here are some old comments, which may or may not be correct:
1258 * minlen == 0 is possible if regstclass is \b or \B,
1259 * and the fixed substr is ''$.
1260 * Since minlen is already taken into account, rx_origin+1 is
1261 * before strend; accidentally, minlen >= 1 guaranties no false
1262 * positives at rx_origin + 1 even for \b or \B. But (minlen? 1 :
1263 * 0) below assumes that regstclass does not come from lookahead...
1264 * If regstclass takes bytelength more than 1: If charlength==1, OK.
1265 * This leaves EXACTF-ish only, which are dealt with in
1269 if (prog->anchored_substr || prog->anchored_utf8 || ml_anch)
1270 endpos= HOP3c(rx_origin, (prog->minlen ? cl_l : 0), strend);
1271 else if (prog->float_substr || prog->float_utf8) {
1272 rx_max_float = HOP3c(check_at, -start_shift, strbeg);
1273 endpos= HOP3c(rx_max_float, cl_l, strend);
1278 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
1279 " looking for class: start_shift: %"IVdf" check_at: %"IVdf
1280 " rx_origin: %"IVdf" endpos: %"IVdf"\n",
1281 (IV)start_shift, (IV)(check_at - strbeg),
1282 (IV)(rx_origin - strbeg), (IV)(endpos - strbeg)));
1284 s = find_byclass(prog, progi->regstclass, rx_origin, endpos,
1287 if (endpos == strend) {
1288 DEBUG_EXECUTE_r( PerlIO_printf(Perl_debug_log,
1289 " Could not match STCLASS...\n") );
1292 DEBUG_EXECUTE_r( PerlIO_printf(Perl_debug_log,
1293 " This position contradicts STCLASS...\n") );
1294 if ((prog->intflags & PREGf_ANCH) && !ml_anch
1295 && !(prog->intflags & PREGf_IMPLICIT))
1298 /* Contradict one of substrings */
1299 if (prog->anchored_substr || prog->anchored_utf8) {
1300 if (prog->substrs->check_ix == 1) { /* check is float */
1301 /* Have both, check_string is floating */
1302 assert(rx_origin + start_shift <= check_at);
1303 if (rx_origin + start_shift != check_at) {
1304 /* not at latest position float substr could match:
1305 * Recheck anchored substring, but not floating.
1306 * The condition above is in bytes rather than
1307 * chars for efficiency. It's conservative, in
1308 * that it errs on the side of doing 'goto
1309 * do_other_substr', where a more accurate
1310 * char-based calculation will be done */
1311 DEBUG_EXECUTE_r( PerlIO_printf(Perl_debug_log,
1312 " Looking for anchored substr starting at offset %ld...\n",
1313 (long)(other_last - strpos)) );
1314 goto do_other_substr;
1322 /* In the presence of ml_anch, we might be able to
1323 * find another \n without breaking the current float
1326 /* strictly speaking this should be HOP3c(..., 1, ...),
1327 * but since we goto a block of code that's going to
1328 * search for the next \n if any, its safe here */
1330 DEBUG_EXECUTE_r( PerlIO_printf(Perl_debug_log,
1331 " Looking for /%s^%s/m starting at offset %ld...\n",
1332 PL_colors[0], PL_colors[1],
1333 (long)(rx_origin - strpos)) );
1334 goto postprocess_substr_matches;
1337 /* strictly speaking this can never be true; but might
1338 * be if we ever allow intuit without substrings */
1339 if (!(utf8_target ? prog->float_utf8 : prog->float_substr))
1342 rx_origin = rx_max_float;
1345 /* at this point, any matching substrings have been
1346 * contradicted. Start again... */
1348 rx_origin = HOP3c(rx_origin, 1, strend);
1350 /* uses bytes rather than char calculations for efficiency.
1351 * It's conservative: it errs on the side of doing 'goto restart',
1352 * where there is code that does a proper char-based test */
1353 if (rx_origin + start_shift + end_shift > strend) {
1354 DEBUG_EXECUTE_r( PerlIO_printf(Perl_debug_log,
1355 " Could not match STCLASS...\n") );
1358 DEBUG_EXECUTE_r( PerlIO_printf(Perl_debug_log,
1359 " Looking for %s substr starting at offset %ld...\n",
1360 (prog->substrs->check_ix ? "floating" : "anchored"),
1361 (long)(rx_origin + start_shift - strpos)) );
1367 if (rx_origin != s) {
1368 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
1369 " By STCLASS: moving %ld --> %ld\n",
1370 (long)(rx_origin - strpos), (long)(s - strpos))
1374 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
1375 " Does not contradict STCLASS...\n");
1380 /* Decide whether using the substrings helped */
1382 if (rx_origin != strpos) {
1383 /* Fixed substring is found far enough so that the match
1384 cannot start at strpos. */
1386 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log, " try at offset...\n"));
1387 ++BmUSEFUL(utf8_target ? prog->check_utf8 : prog->check_substr); /* hooray/5 */
1390 /* The found rx_origin position does not prohibit matching at
1391 * strpos, so calling intuit didn't gain us anything. Decrement
1392 * the BmUSEFUL() count on the check substring, and if we reach
1394 if (!(prog->intflags & PREGf_NAUGHTY)
1396 prog->check_utf8 /* Could be deleted already */
1397 && --BmUSEFUL(prog->check_utf8) < 0
1398 && (prog->check_utf8 == prog->float_utf8)
1400 prog->check_substr /* Could be deleted already */
1401 && --BmUSEFUL(prog->check_substr) < 0
1402 && (prog->check_substr == prog->float_substr)
1405 /* If flags & SOMETHING - do not do it many times on the same match */
1406 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log, " ... Disabling check substring...\n"));
1407 /* XXX Does the destruction order has to change with utf8_target? */
1408 SvREFCNT_dec(utf8_target ? prog->check_utf8 : prog->check_substr);
1409 SvREFCNT_dec(utf8_target ? prog->check_substr : prog->check_utf8);
1410 prog->check_substr = prog->check_utf8 = NULL; /* disable */
1411 prog->float_substr = prog->float_utf8 = NULL; /* clear */
1412 check = NULL; /* abort */
1413 /* XXXX This is a remnant of the old implementation. It
1414 looks wasteful, since now INTUIT can use many
1415 other heuristics. */
1416 prog->extflags &= ~RXf_USE_INTUIT;
1420 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
1421 "Intuit: %sSuccessfully guessed:%s match at offset %ld\n",
1422 PL_colors[4], PL_colors[5], (long)(rx_origin - strpos)) );
1426 fail_finish: /* Substring not found */
1427 if (prog->check_substr || prog->check_utf8) /* could be removed already */
1428 BmUSEFUL(utf8_target ? prog->check_utf8 : prog->check_substr) += 5; /* hooray */
1430 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log, "%sMatch rejected by optimizer%s\n",
1431 PL_colors[4], PL_colors[5]));
1436 #define DECL_TRIE_TYPE(scan) \
1437 const enum { trie_plain, trie_utf8, trie_utf8_fold, trie_latin_utf8_fold, \
1438 trie_utf8_exactfa_fold, trie_latin_utf8_exactfa_fold } \
1439 trie_type = ((scan->flags == EXACT) \
1440 ? (utf8_target ? trie_utf8 : trie_plain) \
1441 : (scan->flags == EXACTFA) \
1442 ? (utf8_target ? trie_utf8_exactfa_fold : trie_latin_utf8_exactfa_fold) \
1443 : (utf8_target ? trie_utf8_fold : trie_latin_utf8_fold))
1445 #define REXEC_TRIE_READ_CHAR(trie_type, trie, widecharmap, uc, uscan, len, uvc, charid, foldlen, foldbuf, uniflags) \
1448 U8 flags = FOLD_FLAGS_FULL; \
1449 switch (trie_type) { \
1450 case trie_utf8_exactfa_fold: \
1451 flags |= FOLD_FLAGS_NOMIX_ASCII; \
1453 case trie_utf8_fold: \
1454 if ( foldlen>0 ) { \
1455 uvc = utf8n_to_uvchr( (const U8*) uscan, UTF8_MAXLEN, &len, uniflags ); \
1460 uvc = _to_utf8_fold_flags( (const U8*) uc, foldbuf, &foldlen, flags); \
1461 len = UTF8SKIP(uc); \
1462 skiplen = UNISKIP( uvc ); \
1463 foldlen -= skiplen; \
1464 uscan = foldbuf + skiplen; \
1467 case trie_latin_utf8_exactfa_fold: \
1468 flags |= FOLD_FLAGS_NOMIX_ASCII; \
1470 case trie_latin_utf8_fold: \
1471 if ( foldlen>0 ) { \
1472 uvc = utf8n_to_uvchr( (const U8*) uscan, UTF8_MAXLEN, &len, uniflags ); \
1478 uvc = _to_fold_latin1( (U8) *uc, foldbuf, &foldlen, flags); \
1479 skiplen = UNISKIP( uvc ); \
1480 foldlen -= skiplen; \
1481 uscan = foldbuf + skiplen; \
1485 uvc = utf8n_to_uvchr( (const U8*) uc, UTF8_MAXLEN, &len, uniflags ); \
1492 charid = trie->charmap[ uvc ]; \
1496 if (widecharmap) { \
1497 SV** const svpp = hv_fetch(widecharmap, \
1498 (char*)&uvc, sizeof(UV), 0); \
1500 charid = (U16)SvIV(*svpp); \
1505 #define REXEC_FBC_EXACTISH_SCAN(COND) \
1509 && (ln == 1 || folder(s, pat_string, ln)) \
1510 && (reginfo->intuit || regtry(reginfo, &s)) )\
1516 #define REXEC_FBC_UTF8_SCAN(CODE) \
1518 while (s < strend) { \
1524 #define REXEC_FBC_SCAN(CODE) \
1526 while (s < strend) { \
1532 #define REXEC_FBC_UTF8_CLASS_SCAN(COND) \
1533 REXEC_FBC_UTF8_SCAN( \
1535 if (tmp && (reginfo->intuit || regtry(reginfo, &s))) \
1544 #define REXEC_FBC_CLASS_SCAN(COND) \
1547 if (tmp && (reginfo->intuit || regtry(reginfo, &s))) \
1556 #define REXEC_FBC_TRYIT \
1557 if ((reginfo->intuit || regtry(reginfo, &s))) \
1560 #define REXEC_FBC_CSCAN(CONDUTF8,COND) \
1561 if (utf8_target) { \
1562 REXEC_FBC_UTF8_CLASS_SCAN(CONDUTF8); \
1565 REXEC_FBC_CLASS_SCAN(COND); \
1568 #define DUMP_EXEC_POS(li,s,doutf8) \
1569 dump_exec_pos(li,s,(reginfo->strend),(reginfo->strbeg), \
1573 #define FBC_UTF8_A(TEST_NON_UTF8, IF_SUCCESS, IF_FAIL) \
1574 tmp = (s != reginfo->strbeg) ? UCHARAT(s - 1) : '\n'; \
1575 tmp = TEST_NON_UTF8(tmp); \
1576 REXEC_FBC_UTF8_SCAN( \
1577 if (tmp == ! TEST_NON_UTF8((U8) *s)) { \
1586 #define FBC_UTF8(TEST_UV, TEST_UTF8, IF_SUCCESS, IF_FAIL) \
1587 if (s == reginfo->strbeg) { \
1591 U8 * const r = reghop3((U8*)s, -1, (U8*)reginfo->strbeg); \
1592 tmp = utf8n_to_uvchr(r, (U8*) reginfo->strend - r, \
1593 0, UTF8_ALLOW_DEFAULT); \
1595 tmp = TEST_UV(tmp); \
1596 LOAD_UTF8_CHARCLASS_ALNUM(); \
1597 REXEC_FBC_UTF8_SCAN( \
1598 if (tmp == ! (TEST_UTF8((U8 *) s))) { \
1607 /* The only difference between the BOUND and NBOUND cases is that
1608 * REXEC_FBC_TRYIT is called when matched in BOUND, and when non-matched in
1609 * NBOUND. This is accomplished by passing it in either the if or else clause,
1610 * with the other one being empty */
1611 #define FBC_BOUND(TEST_NON_UTF8, TEST_UV, TEST_UTF8) \
1612 FBC_BOUND_COMMON(FBC_UTF8(TEST_UV, TEST_UTF8, REXEC_FBC_TRYIT, PLACEHOLDER), TEST_NON_UTF8, REXEC_FBC_TRYIT, PLACEHOLDER)
1614 #define FBC_BOUND_A(TEST_NON_UTF8, TEST_UV, TEST_UTF8) \
1615 FBC_BOUND_COMMON(FBC_UTF8_A(TEST_NON_UTF8, REXEC_FBC_TRYIT, PLACEHOLDER), TEST_NON_UTF8, REXEC_FBC_TRYIT, PLACEHOLDER)
1617 #define FBC_NBOUND(TEST_NON_UTF8, TEST_UV, TEST_UTF8) \
1618 FBC_BOUND_COMMON(FBC_UTF8(TEST_UV, TEST_UTF8, PLACEHOLDER, REXEC_FBC_TRYIT), TEST_NON_UTF8, PLACEHOLDER, REXEC_FBC_TRYIT)
1620 #define FBC_NBOUND_A(TEST_NON_UTF8, TEST_UV, TEST_UTF8) \
1621 FBC_BOUND_COMMON(FBC_UTF8_A(TEST_NON_UTF8, PLACEHOLDER, REXEC_FBC_TRYIT), TEST_NON_UTF8, PLACEHOLDER, REXEC_FBC_TRYIT)
1623 /* Common to the BOUND and NBOUND cases. We
1624 * are looking for the boundary (or non-boundary between a word and non-word
1625 * character. The utf8 and non-utf8 cases have the same logic, but the details
1626 * must be different. Find the "wordness" of the character just prior to this
1627 * one, and compare it with the wordness of this one. If they differ, we have
1628 * a boundary. At the beginning of the string, pretend that the previous
1629 * character was a new-line.
1631 * 'tmp' below in the REXEC_FBC_SCAN loop is a loop invariant, a bool giving
1632 * the return of TEST_NON_UTF8(s-1). To see this, note that that's what it is
1633 * defined to be at entry to the loop, and to get to the IF_FAIL branch, tmp
1634 * must equal TEST_NON_UTF8(s), and in the opposite branch, IF_SUCCESS, tmp is
1635 * that complement. But in that branch we complement tmp, meaning that at the
1636 * bottom of the loop tmp is always going to be equal to TEST_NON_UTF8(s),
1637 * which means at the top of the loop in the next iteration, it is
1638 * TEST_NON_UTF8(s-1) */
1639 #define FBC_BOUND_COMMON(UTF8_CODE, TEST_NON_UTF8, IF_SUCCESS, IF_FAIL) \
1640 if (utf8_target) { \
1643 else { /* Not utf8 */ \
1644 tmp = (s != reginfo->strbeg) ? UCHARAT(s - 1) : '\n'; \
1645 tmp = TEST_NON_UTF8(tmp); \
1647 if (tmp == ! TEST_NON_UTF8((U8) *s)) { \
1656 if ((!prog->minlen && tmp) && (reginfo->intuit || regtry(reginfo, &s))) \
1659 /* We know what class REx starts with. Try to find this position... */
1660 /* if reginfo->intuit, its a dryrun */
1661 /* annoyingly all the vars in this routine have different names from their counterparts
1662 in regmatch. /grrr */
1665 S_find_byclass(pTHX_ regexp * prog, const regnode *c, char *s,
1666 const char *strend, regmatch_info *reginfo)
1669 const I32 doevery = (prog->intflags & PREGf_SKIP) == 0;
1670 char *pat_string; /* The pattern's exactish string */
1671 char *pat_end; /* ptr to end char of pat_string */
1672 re_fold_t folder; /* Function for computing non-utf8 folds */
1673 const U8 *fold_array; /* array for folding ords < 256 */
1679 I32 tmp = 1; /* Scratch variable? */
1680 const bool utf8_target = reginfo->is_utf8_target;
1681 UV utf8_fold_flags = 0;
1682 const bool is_utf8_pat = reginfo->is_utf8_pat;
1683 bool to_complement = FALSE; /* Invert the result? Taking the xor of this
1684 with a result inverts that result, as 0^1 =
1686 _char_class_number classnum;
1688 RXi_GET_DECL(prog,progi);
1690 PERL_ARGS_ASSERT_FIND_BYCLASS;
1692 /* We know what class it must start with. */
1696 REXEC_FBC_UTF8_CLASS_SCAN(
1697 reginclass(prog, c, (U8*)s, (U8*) strend, utf8_target));
1700 REXEC_FBC_CLASS_SCAN(REGINCLASS(prog, c, (U8*)s));
1705 if (tmp && (reginfo->intuit || regtry(reginfo, &s)))
1712 case EXACTFA_NO_TRIE: /* This node only generated for non-utf8 patterns */
1713 assert(! is_utf8_pat);
1716 if (is_utf8_pat || utf8_target) {
1717 utf8_fold_flags = FOLDEQ_UTF8_NOMIX_ASCII;
1718 goto do_exactf_utf8;
1720 fold_array = PL_fold_latin1; /* Latin1 folds are not affected by */
1721 folder = foldEQ_latin1; /* /a, except the sharp s one which */
1722 goto do_exactf_non_utf8; /* isn't dealt with by these */
1724 case EXACTF: /* This node only generated for non-utf8 patterns */
1725 assert(! is_utf8_pat);
1727 utf8_fold_flags = 0;
1728 goto do_exactf_utf8;
1730 fold_array = PL_fold;
1732 goto do_exactf_non_utf8;
1735 if (is_utf8_pat || utf8_target || IN_UTF8_CTYPE_LOCALE) {
1736 utf8_fold_flags = FOLDEQ_LOCALE;
1737 goto do_exactf_utf8;
1739 fold_array = PL_fold_locale;
1740 folder = foldEQ_locale;
1741 goto do_exactf_non_utf8;
1745 utf8_fold_flags = FOLDEQ_S2_ALREADY_FOLDED;
1747 goto do_exactf_utf8;
1750 if (is_utf8_pat || utf8_target) {
1751 utf8_fold_flags = is_utf8_pat ? FOLDEQ_S2_ALREADY_FOLDED : 0;
1752 goto do_exactf_utf8;
1755 /* Any 'ss' in the pattern should have been replaced by regcomp,
1756 * so we don't have to worry here about this single special case
1757 * in the Latin1 range */
1758 fold_array = PL_fold_latin1;
1759 folder = foldEQ_latin1;
1763 do_exactf_non_utf8: /* Neither pattern nor string are UTF8, and there
1764 are no glitches with fold-length differences
1765 between the target string and pattern */
1767 /* The idea in the non-utf8 EXACTF* cases is to first find the
1768 * first character of the EXACTF* node and then, if necessary,
1769 * case-insensitively compare the full text of the node. c1 is the
1770 * first character. c2 is its fold. This logic will not work for
1771 * Unicode semantics and the german sharp ss, which hence should
1772 * not be compiled into a node that gets here. */
1773 pat_string = STRING(c);
1774 ln = STR_LEN(c); /* length to match in octets/bytes */
1776 /* We know that we have to match at least 'ln' bytes (which is the
1777 * same as characters, since not utf8). If we have to match 3
1778 * characters, and there are only 2 availabe, we know without
1779 * trying that it will fail; so don't start a match past the
1780 * required minimum number from the far end */
1781 e = HOP3c(strend, -((SSize_t)ln), s);
1783 if (reginfo->intuit && e < s) {
1784 e = s; /* Due to minlen logic of intuit() */
1788 c2 = fold_array[c1];
1789 if (c1 == c2) { /* If char and fold are the same */
1790 REXEC_FBC_EXACTISH_SCAN(*(U8*)s == c1);
1793 REXEC_FBC_EXACTISH_SCAN(*(U8*)s == c1 || *(U8*)s == c2);
1801 /* If one of the operands is in utf8, we can't use the simpler folding
1802 * above, due to the fact that many different characters can have the
1803 * same fold, or portion of a fold, or different- length fold */
1804 pat_string = STRING(c);
1805 ln = STR_LEN(c); /* length to match in octets/bytes */
1806 pat_end = pat_string + ln;
1807 lnc = is_utf8_pat /* length to match in characters */
1808 ? utf8_length((U8 *) pat_string, (U8 *) pat_end)
1811 /* We have 'lnc' characters to match in the pattern, but because of
1812 * multi-character folding, each character in the target can match
1813 * up to 3 characters (Unicode guarantees it will never exceed
1814 * this) if it is utf8-encoded; and up to 2 if not (based on the
1815 * fact that the Latin 1 folds are already determined, and the
1816 * only multi-char fold in that range is the sharp-s folding to
1817 * 'ss'. Thus, a pattern character can match as little as 1/3 of a
1818 * string character. Adjust lnc accordingly, rounding up, so that
1819 * if we need to match at least 4+1/3 chars, that really is 5. */
1820 expansion = (utf8_target) ? UTF8_MAX_FOLD_CHAR_EXPAND : 2;
1821 lnc = (lnc + expansion - 1) / expansion;
1823 /* As in the non-UTF8 case, if we have to match 3 characters, and
1824 * only 2 are left, it's guaranteed to fail, so don't start a
1825 * match that would require us to go beyond the end of the string
1827 e = HOP3c(strend, -((SSize_t)lnc), s);
1829 if (reginfo->intuit && e < s) {
1830 e = s; /* Due to minlen logic of intuit() */
1833 /* XXX Note that we could recalculate e to stop the loop earlier,
1834 * as the worst case expansion above will rarely be met, and as we
1835 * go along we would usually find that e moves further to the left.
1836 * This would happen only after we reached the point in the loop
1837 * where if there were no expansion we should fail. Unclear if
1838 * worth the expense */
1841 char *my_strend= (char *)strend;
1842 if (foldEQ_utf8_flags(s, &my_strend, 0, utf8_target,
1843 pat_string, NULL, ln, is_utf8_pat, utf8_fold_flags)
1844 && (reginfo->intuit || regtry(reginfo, &s)) )
1848 s += (utf8_target) ? UTF8SKIP(s) : 1;
1854 FBC_BOUND(isWORDCHAR_LC, isWORDCHAR_LC_uvchr, isWORDCHAR_LC_utf8);
1857 FBC_NBOUND(isWORDCHAR_LC, isWORDCHAR_LC_uvchr, isWORDCHAR_LC_utf8);
1860 FBC_BOUND(isWORDCHAR, isWORDCHAR_uni, isWORDCHAR_utf8);
1863 FBC_BOUND_A(isWORDCHAR_A, isWORDCHAR_A, isWORDCHAR_A);
1866 FBC_NBOUND(isWORDCHAR, isWORDCHAR_uni, isWORDCHAR_utf8);
1869 FBC_NBOUND_A(isWORDCHAR_A, isWORDCHAR_A, isWORDCHAR_A);
1872 FBC_BOUND(isWORDCHAR_L1, isWORDCHAR_uni, isWORDCHAR_utf8);
1875 FBC_NBOUND(isWORDCHAR_L1, isWORDCHAR_uni, isWORDCHAR_utf8);
1878 REXEC_FBC_CSCAN(is_LNBREAK_utf8_safe(s, strend),
1879 is_LNBREAK_latin1_safe(s, strend)
1883 /* The argument to all the POSIX node types is the class number to pass to
1884 * _generic_isCC() to build a mask for searching in PL_charclass[] */
1891 REXEC_FBC_CSCAN(to_complement ^ cBOOL(isFOO_utf8_lc(FLAGS(c), (U8 *) s)),
1892 to_complement ^ cBOOL(isFOO_lc(FLAGS(c), *s)));
1907 /* The complement of something that matches only ASCII matches all
1908 * non-ASCII, plus everything in ASCII that isn't in the class. */
1909 REXEC_FBC_UTF8_CLASS_SCAN(! isASCII_utf8(s)
1910 || ! _generic_isCC_A(*s, FLAGS(c)));
1919 /* Don't need to worry about utf8, as it can match only a single
1920 * byte invariant character. */
1921 REXEC_FBC_CLASS_SCAN(
1922 to_complement ^ cBOOL(_generic_isCC_A(*s, FLAGS(c))));
1930 if (! utf8_target) {
1931 REXEC_FBC_CLASS_SCAN(to_complement ^ cBOOL(_generic_isCC(*s,
1937 classnum = (_char_class_number) FLAGS(c);
1938 if (classnum < _FIRST_NON_SWASH_CC) {
1939 while (s < strend) {
1941 /* We avoid loading in the swash as long as possible, but
1942 * should we have to, we jump to a separate loop. This
1943 * extra 'if' statement is what keeps this code from being
1944 * just a call to REXEC_FBC_UTF8_CLASS_SCAN() */
1945 if (UTF8_IS_ABOVE_LATIN1(*s)) {
1946 goto found_above_latin1;
1948 if ((UTF8_IS_INVARIANT(*s)
1949 && to_complement ^ cBOOL(_generic_isCC((U8) *s,
1951 || (UTF8_IS_DOWNGRADEABLE_START(*s)
1952 && to_complement ^ cBOOL(
1953 _generic_isCC(TWO_BYTE_UTF8_TO_NATIVE(*s,
1957 if (tmp && (reginfo->intuit || regtry(reginfo, &s)))
1969 else switch (classnum) { /* These classes are implemented as
1971 case _CC_ENUM_SPACE: /* XXX would require separate code if we
1972 revert the change of \v matching this */
1975 case _CC_ENUM_PSXSPC:
1976 REXEC_FBC_UTF8_CLASS_SCAN(
1977 to_complement ^ cBOOL(isSPACE_utf8(s)));
1980 case _CC_ENUM_BLANK:
1981 REXEC_FBC_UTF8_CLASS_SCAN(
1982 to_complement ^ cBOOL(isBLANK_utf8(s)));
1985 case _CC_ENUM_XDIGIT:
1986 REXEC_FBC_UTF8_CLASS_SCAN(
1987 to_complement ^ cBOOL(isXDIGIT_utf8(s)));
1990 case _CC_ENUM_VERTSPACE:
1991 REXEC_FBC_UTF8_CLASS_SCAN(
1992 to_complement ^ cBOOL(isVERTWS_utf8(s)));
1995 case _CC_ENUM_CNTRL:
1996 REXEC_FBC_UTF8_CLASS_SCAN(
1997 to_complement ^ cBOOL(isCNTRL_utf8(s)));
2001 Perl_croak(aTHX_ "panic: find_byclass() node %d='%s' has an unexpected character class '%d'", OP(c), PL_reg_name[OP(c)], classnum);
2002 assert(0); /* NOTREACHED */
2007 found_above_latin1: /* Here we have to load a swash to get the result
2008 for the current code point */
2009 if (! PL_utf8_swash_ptrs[classnum]) {
2010 U8 flags = _CORE_SWASH_INIT_ACCEPT_INVLIST;
2011 PL_utf8_swash_ptrs[classnum] =
2012 _core_swash_init("utf8",
2015 PL_XPosix_ptrs[classnum], &flags);
2018 /* This is a copy of the loop above for swash classes, though using the
2019 * FBC macro instead of being expanded out. Since we've loaded the
2020 * swash, we don't have to check for that each time through the loop */
2021 REXEC_FBC_UTF8_CLASS_SCAN(
2022 to_complement ^ cBOOL(_generic_utf8(
2025 swash_fetch(PL_utf8_swash_ptrs[classnum],
2033 /* what trie are we using right now */
2034 reg_ac_data *aho = (reg_ac_data*)progi->data->data[ ARG( c ) ];
2035 reg_trie_data *trie = (reg_trie_data*)progi->data->data[ aho->trie ];
2036 HV *widecharmap = MUTABLE_HV(progi->data->data[ aho->trie + 1 ]);
2038 const char *last_start = strend - trie->minlen;
2040 const char *real_start = s;
2042 STRLEN maxlen = trie->maxlen;
2044 U8 **points; /* map of where we were in the input string
2045 when reading a given char. For ASCII this
2046 is unnecessary overhead as the relationship
2047 is always 1:1, but for Unicode, especially
2048 case folded Unicode this is not true. */
2049 U8 foldbuf[ UTF8_MAXBYTES_CASE + 1 ];
2053 GET_RE_DEBUG_FLAGS_DECL;
2055 /* We can't just allocate points here. We need to wrap it in
2056 * an SV so it gets freed properly if there is a croak while
2057 * running the match */
2060 sv_points=newSV(maxlen * sizeof(U8 *));
2061 SvCUR_set(sv_points,
2062 maxlen * sizeof(U8 *));
2063 SvPOK_on(sv_points);
2064 sv_2mortal(sv_points);
2065 points=(U8**)SvPV_nolen(sv_points );
2066 if ( trie_type != trie_utf8_fold
2067 && (trie->bitmap || OP(c)==AHOCORASICKC) )
2070 bitmap=(U8*)trie->bitmap;
2072 bitmap=(U8*)ANYOF_BITMAP(c);
2074 /* this is the Aho-Corasick algorithm modified a touch
2075 to include special handling for long "unknown char" sequences.
2076 The basic idea being that we use AC as long as we are dealing
2077 with a possible matching char, when we encounter an unknown char
2078 (and we have not encountered an accepting state) we scan forward
2079 until we find a legal starting char.
2080 AC matching is basically that of trie matching, except that when
2081 we encounter a failing transition, we fall back to the current
2082 states "fail state", and try the current char again, a process
2083 we repeat until we reach the root state, state 1, or a legal
2084 transition. If we fail on the root state then we can either
2085 terminate if we have reached an accepting state previously, or
2086 restart the entire process from the beginning if we have not.
2089 while (s <= last_start) {
2090 const U32 uniflags = UTF8_ALLOW_DEFAULT;
2098 U8 *uscan = (U8*)NULL;
2099 U8 *leftmost = NULL;
2101 U32 accepted_word= 0;
2105 while ( state && uc <= (U8*)strend ) {
2107 U32 word = aho->states[ state ].wordnum;
2111 DEBUG_TRIE_EXECUTE_r(
2112 if ( uc <= (U8*)last_start && !BITMAP_TEST(bitmap,*uc) ) {
2113 dump_exec_pos( (char *)uc, c, strend, real_start,
2114 (char *)uc, utf8_target );
2115 PerlIO_printf( Perl_debug_log,
2116 " Scanning for legal start char...\n");
2120 while ( uc <= (U8*)last_start && !BITMAP_TEST(bitmap,*uc) ) {
2124 while ( uc <= (U8*)last_start && !BITMAP_TEST(bitmap,*uc) ) {
2130 if (uc >(U8*)last_start) break;
2134 U8 *lpos= points[ (pointpos - trie->wordinfo[word].len) % maxlen ];
2135 if (!leftmost || lpos < leftmost) {
2136 DEBUG_r(accepted_word=word);
2142 points[pointpos++ % maxlen]= uc;
2143 if (foldlen || uc < (U8*)strend) {
2144 REXEC_TRIE_READ_CHAR(trie_type, trie,
2146 uscan, len, uvc, charid, foldlen,
2148 DEBUG_TRIE_EXECUTE_r({
2149 dump_exec_pos( (char *)uc, c, strend,
2150 real_start, s, utf8_target);
2151 PerlIO_printf(Perl_debug_log,
2152 " Charid:%3u CP:%4"UVxf" ",
2164 word = aho->states[ state ].wordnum;
2166 base = aho->states[ state ].trans.base;
2168 DEBUG_TRIE_EXECUTE_r({
2170 dump_exec_pos( (char *)uc, c, strend, real_start,
2172 PerlIO_printf( Perl_debug_log,
2173 "%sState: %4"UVxf", word=%"UVxf,
2174 failed ? " Fail transition to " : "",
2175 (UV)state, (UV)word);
2181 ( ((offset = base + charid
2182 - 1 - trie->uniquecharcount)) >= 0)
2183 && ((U32)offset < trie->lasttrans)
2184 && trie->trans[offset].check == state
2185 && (tmp=trie->trans[offset].next))
2187 DEBUG_TRIE_EXECUTE_r(
2188 PerlIO_printf( Perl_debug_log," - legal\n"));
2193 DEBUG_TRIE_EXECUTE_r(
2194 PerlIO_printf( Perl_debug_log," - fail\n"));
2196 state = aho->fail[state];
2200 /* we must be accepting here */
2201 DEBUG_TRIE_EXECUTE_r(
2202 PerlIO_printf( Perl_debug_log," - accepting\n"));
2211 if (!state) state = 1;
2214 if ( aho->states[ state ].wordnum ) {
2215 U8 *lpos = points[ (pointpos - trie->wordinfo[aho->states[ state ].wordnum].len) % maxlen ];
2216 if (!leftmost || lpos < leftmost) {
2217 DEBUG_r(accepted_word=aho->states[ state ].wordnum);
2222 s = (char*)leftmost;
2223 DEBUG_TRIE_EXECUTE_r({
2225 Perl_debug_log,"Matches word #%"UVxf" at position %"IVdf". Trying full pattern...\n",
2226 (UV)accepted_word, (IV)(s - real_start)
2229 if (reginfo->intuit || regtry(reginfo, &s)) {
2235 DEBUG_TRIE_EXECUTE_r({
2236 PerlIO_printf( Perl_debug_log,"Pattern failed. Looking for new start point...\n");
2239 DEBUG_TRIE_EXECUTE_r(
2240 PerlIO_printf( Perl_debug_log,"No match.\n"));
2249 Perl_croak(aTHX_ "panic: unknown regstclass %d", (int)OP(c));
2256 /* set RX_SAVED_COPY, RX_SUBBEG etc.
2257 * flags have same meanings as with regexec_flags() */
2260 S_reg_set_capture_string(pTHX_ REGEXP * const rx,
2267 struct regexp *const prog = ReANY(rx);
2269 if (flags & REXEC_COPY_STR) {
2273 PerlIO_printf(Perl_debug_log,
2274 "Copy on write: regexp capture, type %d\n",
2277 /* Create a new COW SV to share the match string and store
2278 * in saved_copy, unless the current COW SV in saved_copy
2279 * is valid and suitable for our purpose */
2280 if (( prog->saved_copy
2281 && SvIsCOW(prog->saved_copy)
2282 && SvPOKp(prog->saved_copy)
2285 && SvPVX(sv) == SvPVX(prog->saved_copy)))
2287 /* just reuse saved_copy SV */
2288 if (RXp_MATCH_COPIED(prog)) {
2289 Safefree(prog->subbeg);
2290 RXp_MATCH_COPIED_off(prog);
2294 /* create new COW SV to share string */
2295 RX_MATCH_COPY_FREE(rx);
2296 prog->saved_copy = sv_setsv_cow(prog->saved_copy, sv);
2298 prog->subbeg = (char *)SvPVX_const(prog->saved_copy);
2299 assert (SvPOKp(prog->saved_copy));
2300 prog->sublen = strend - strbeg;
2301 prog->suboffset = 0;
2302 prog->subcoffset = 0;
2307 SSize_t max = strend - strbeg;
2310 if ( (flags & REXEC_COPY_SKIP_POST)
2311 && !(prog->extflags & RXf_PMf_KEEPCOPY) /* //p */
2312 && !(PL_sawampersand & SAWAMPERSAND_RIGHT)
2313 ) { /* don't copy $' part of string */
2316 /* calculate the right-most part of the string covered
2317 * by a capture. Due to look-ahead, this may be to
2318 * the right of $&, so we have to scan all captures */
2319 while (n <= prog->lastparen) {
2320 if (prog->offs[n].end > max)
2321 max = prog->offs[n].end;
2325 max = (PL_sawampersand & SAWAMPERSAND_LEFT)
2326 ? prog->offs[0].start
2328 assert(max >= 0 && max <= strend - strbeg);
2331 if ( (flags & REXEC_COPY_SKIP_PRE)
2332 && !(prog->extflags & RXf_PMf_KEEPCOPY) /* //p */
2333 && !(PL_sawampersand & SAWAMPERSAND_LEFT)
2334 ) { /* don't copy $` part of string */
2337 /* calculate the left-most part of the string covered
2338 * by a capture. Due to look-behind, this may be to
2339 * the left of $&, so we have to scan all captures */
2340 while (min && n <= prog->lastparen) {
2341 if ( prog->offs[n].start != -1
2342 && prog->offs[n].start < min)
2344 min = prog->offs[n].start;
2348 if ((PL_sawampersand & SAWAMPERSAND_RIGHT)
2349 && min > prog->offs[0].end
2351 min = prog->offs[0].end;
2355 assert(min >= 0 && min <= max && min <= strend - strbeg);
2358 if (RX_MATCH_COPIED(rx)) {
2359 if (sublen > prog->sublen)
2361 (char*)saferealloc(prog->subbeg, sublen+1);
2364 prog->subbeg = (char*)safemalloc(sublen+1);
2365 Copy(strbeg + min, prog->subbeg, sublen, char);
2366 prog->subbeg[sublen] = '\0';
2367 prog->suboffset = min;
2368 prog->sublen = sublen;
2369 RX_MATCH_COPIED_on(rx);
2371 prog->subcoffset = prog->suboffset;
2372 if (prog->suboffset && utf8_target) {
2373 /* Convert byte offset to chars.
2374 * XXX ideally should only compute this if @-/@+
2375 * has been seen, a la PL_sawampersand ??? */
2377 /* If there's a direct correspondence between the
2378 * string which we're matching and the original SV,
2379 * then we can use the utf8 len cache associated with
2380 * the SV. In particular, it means that under //g,
2381 * sv_pos_b2u() will use the previously cached
2382 * position to speed up working out the new length of
2383 * subcoffset, rather than counting from the start of
2384 * the string each time. This stops
2385 * $x = "\x{100}" x 1E6; 1 while $x =~ /(.)/g;
2386 * from going quadratic */
2387 if (SvPOKp(sv) && SvPVX(sv) == strbeg)
2388 prog->subcoffset = sv_pos_b2u_flags(sv, prog->subcoffset,
2389 SV_GMAGIC|SV_CONST_RETURN);
2391 prog->subcoffset = utf8_length((U8*)strbeg,
2392 (U8*)(strbeg+prog->suboffset));
2396 RX_MATCH_COPY_FREE(rx);
2397 prog->subbeg = strbeg;
2398 prog->suboffset = 0;
2399 prog->subcoffset = 0;
2400 prog->sublen = strend - strbeg;
2408 - regexec_flags - match a regexp against a string
2411 Perl_regexec_flags(pTHX_ REGEXP * const rx, char *stringarg, char *strend,
2412 char *strbeg, SSize_t minend, SV *sv, void *data, U32 flags)
2413 /* stringarg: the point in the string at which to begin matching */
2414 /* strend: pointer to null at end of string */
2415 /* strbeg: real beginning of string */
2416 /* minend: end of match must be >= minend bytes after stringarg. */
2417 /* sv: SV being matched: only used for utf8 flag, pos() etc; string
2418 * itself is accessed via the pointers above */
2419 /* data: May be used for some additional optimizations.
2420 Currently unused. */
2421 /* flags: For optimizations. See REXEC_* in regexp.h */
2424 struct regexp *const prog = ReANY(rx);
2428 SSize_t minlen; /* must match at least this many chars */
2429 SSize_t dontbother = 0; /* how many characters not to try at end */
2430 const bool utf8_target = cBOOL(DO_UTF8(sv));
2432 RXi_GET_DECL(prog,progi);
2433 regmatch_info reginfo_buf; /* create some info to pass to regtry etc */
2434 regmatch_info *const reginfo = ®info_buf;
2435 regexp_paren_pair *swap = NULL;
2437 GET_RE_DEBUG_FLAGS_DECL;
2439 PERL_ARGS_ASSERT_REGEXEC_FLAGS;
2440 PERL_UNUSED_ARG(data);
2442 /* Be paranoid... */
2443 if (prog == NULL || stringarg == NULL) {
2444 Perl_croak(aTHX_ "NULL regexp parameter");
2448 debug_start_match(rx, utf8_target, stringarg, strend,
2452 startpos = stringarg;
2454 if (prog->intflags & PREGf_GPOS_SEEN) {
2457 /* set reginfo->ganch, the position where \G can match */
2460 (flags & REXEC_IGNOREPOS)
2461 ? stringarg /* use start pos rather than pos() */
2462 : (sv && (mg = mg_find_mglob(sv)) && mg->mg_len >= 0)
2463 /* Defined pos(): */
2464 ? strbeg + MgBYTEPOS(mg, sv, strbeg, strend-strbeg)
2465 : strbeg; /* pos() not defined; use start of string */
2467 DEBUG_GPOS_r(PerlIO_printf(Perl_debug_log,
2468 "GPOS ganch set to strbeg[%"IVdf"]\n", (IV)(reginfo->ganch - strbeg)));
2470 /* in the presence of \G, we may need to start looking earlier in
2471 * the string than the suggested start point of stringarg:
2472 * if prog->gofs is set, then that's a known, fixed minimum
2475 * /ab|c\G/: gofs = 1
2476 * or if the minimum offset isn't known, then we have to go back
2477 * to the start of the string, e.g. /w+\G/
2480 if (prog->intflags & PREGf_ANCH_GPOS) {
2481 startpos = reginfo->ganch - prog->gofs;
2483 ((flags & REXEC_FAIL_ON_UNDERFLOW) ? stringarg : strbeg))
2485 DEBUG_r(PerlIO_printf(Perl_debug_log,
2486 "fail: ganch-gofs before earliest possible start\n"));
2490 else if (prog->gofs) {
2491 if (startpos - prog->gofs < strbeg)
2494 startpos -= prog->gofs;
2496 else if (prog->intflags & PREGf_GPOS_FLOAT)
2500 minlen = prog->minlen;
2501 if ((startpos + minlen) > strend || startpos < strbeg) {
2502 DEBUG_r(PerlIO_printf(Perl_debug_log,
2503 "Regex match can't succeed, so not even tried\n"));
2507 /* at the end of this function, we'll do a LEAVE_SCOPE(oldsave),
2508 * which will call destuctors to reset PL_regmatch_state, free higher
2509 * PL_regmatch_slabs, and clean up regmatch_info_aux and
2510 * regmatch_info_aux_eval */
2512 oldsave = PL_savestack_ix;
2516 if ((prog->extflags & RXf_USE_INTUIT)
2517 && !(flags & REXEC_CHECKED))
2519 s = re_intuit_start(rx, sv, strbeg, startpos, strend,
2524 if (prog->extflags & RXf_CHECK_ALL) {
2525 /* we can match based purely on the result of INTUIT.
2526 * Set up captures etc just for $& and $-[0]
2527 * (an intuit-only match wont have $1,$2,..) */
2528 assert(!prog->nparens);
2530 /* s/// doesn't like it if $& is earlier than where we asked it to
2531 * start searching (which can happen on something like /.\G/) */
2532 if ( (flags & REXEC_FAIL_ON_UNDERFLOW)
2535 /* this should only be possible under \G */
2536 assert(prog->intflags & PREGf_GPOS_SEEN);
2537 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
2538 "matched, but failing for REXEC_FAIL_ON_UNDERFLOW\n"));
2542 /* match via INTUIT shouldn't have any captures.
2543 * Let @-, @+, $^N know */
2544 prog->lastparen = prog->lastcloseparen = 0;
2545 RX_MATCH_UTF8_set(rx, utf8_target);
2546 prog->offs[0].start = s - strbeg;
2547 prog->offs[0].end = utf8_target
2548 ? (char*)utf8_hop((U8*)s, prog->minlenret) - strbeg
2549 : s - strbeg + prog->minlenret;
2550 if ( !(flags & REXEC_NOT_FIRST) )
2551 S_reg_set_capture_string(aTHX_ rx,
2553 sv, flags, utf8_target);
2559 multiline = prog->extflags & RXf_PMf_MULTILINE;
2561 if (strend - s < (minlen+(prog->check_offset_min<0?prog->check_offset_min:0))) {
2562 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
2563 "String too short [regexec_flags]...\n"));
2567 /* Check validity of program. */
2568 if (UCHARAT(progi->program) != REG_MAGIC) {
2569 Perl_croak(aTHX_ "corrupted regexp program");
2572 RX_MATCH_TAINTED_off(rx);
2574 reginfo->prog = rx; /* Yes, sorry that this is confusing. */
2575 reginfo->intuit = 0;
2576 reginfo->is_utf8_target = cBOOL(utf8_target);
2577 reginfo->is_utf8_pat = cBOOL(RX_UTF8(rx));
2578 reginfo->warned = FALSE;
2579 reginfo->strbeg = strbeg;
2581 reginfo->poscache_maxiter = 0; /* not yet started a countdown */
2582 reginfo->strend = strend;
2583 /* see how far we have to get to not match where we matched before */
2584 reginfo->till = stringarg + minend;
2586 if (prog->extflags & RXf_EVAL_SEEN && SvPADTMP(sv)) {
2587 /* SAVEFREESV, not sv_mortalcopy, as this SV must last until after
2588 S_cleanup_regmatch_info_aux has executed (registered by
2589 SAVEDESTRUCTOR_X below). S_cleanup_regmatch_info_aux modifies
2590 magic belonging to this SV.
2591 Not newSVsv, either, as it does not COW.
2593 assert(!IS_PADGV(sv));
2594 reginfo->sv = newSV(0);
2595 SvSetSV_nosteal(reginfo->sv, sv);
2596 SAVEFREESV(reginfo->sv);
2599 /* reserve next 2 or 3 slots in PL_regmatch_state:
2600 * slot N+0: may currently be in use: skip it
2601 * slot N+1: use for regmatch_info_aux struct
2602 * slot N+2: use for regmatch_info_aux_eval struct if we have (?{})'s
2603 * slot N+3: ready for use by regmatch()
2607 regmatch_state *old_regmatch_state;
2608 regmatch_slab *old_regmatch_slab;
2609 int i, max = (prog->extflags & RXf_EVAL_SEEN) ? 2 : 1;
2611 /* on first ever match, allocate first slab */
2612 if (!PL_regmatch_slab) {
2613 Newx(PL_regmatch_slab, 1, regmatch_slab);
2614 PL_regmatch_slab->prev = NULL;
2615 PL_regmatch_slab->next = NULL;
2616 PL_regmatch_state = SLAB_FIRST(PL_regmatch_slab);
2619 old_regmatch_state = PL_regmatch_state;
2620 old_regmatch_slab = PL_regmatch_slab;
2622 for (i=0; i <= max; i++) {
2624 reginfo->info_aux = &(PL_regmatch_state->u.info_aux);
2626 reginfo->info_aux_eval =
2627 reginfo->info_aux->info_aux_eval =
2628 &(PL_regmatch_state->u.info_aux_eval);
2630 if (++PL_regmatch_state > SLAB_LAST(PL_regmatch_slab))
2631 PL_regmatch_state = S_push_slab(aTHX);
2634 /* note initial PL_regmatch_state position; at end of match we'll
2635 * pop back to there and free any higher slabs */
2637 reginfo->info_aux->old_regmatch_state = old_regmatch_state;
2638 reginfo->info_aux->old_regmatch_slab = old_regmatch_slab;
2639 reginfo->info_aux->poscache = NULL;
2641 SAVEDESTRUCTOR_X(S_cleanup_regmatch_info_aux, reginfo->info_aux);
2643 if ((prog->extflags & RXf_EVAL_SEEN))
2644 S_setup_eval_state(aTHX_ reginfo);
2646 reginfo->info_aux_eval = reginfo->info_aux->info_aux_eval = NULL;
2649 /* If there is a "must appear" string, look for it. */
2651 if (PL_curpm && (PM_GETRE(PL_curpm) == rx)) {
2652 /* We have to be careful. If the previous successful match
2653 was from this regex we don't want a subsequent partially
2654 successful match to clobber the old results.
2655 So when we detect this possibility we add a swap buffer
2656 to the re, and switch the buffer each match. If we fail,
2657 we switch it back; otherwise we leave it swapped.
2660 /* do we need a save destructor here for eval dies? */
2661 Newxz(prog->offs, (prog->nparens + 1), regexp_paren_pair);
2662 DEBUG_BUFFERS_r(PerlIO_printf(Perl_debug_log,
2663 "rex=0x%"UVxf" saving offs: orig=0x%"UVxf" new=0x%"UVxf"\n",
2670 /* Simplest case: anchored match need be tried only once. */
2671 /* [unless only anchor is BOL and multiline is set] */
2672 if (prog->intflags & (PREGf_ANCH & ~PREGf_ANCH_GPOS)) {
2673 if (s == startpos && regtry(reginfo, &s))
2675 else if (multiline || (prog->intflags & (PREGf_IMPLICIT | PREGf_ANCH_MBOL))) /* XXXX SBOL? */
2680 dontbother = minlen - 1;
2681 end = HOP3c(strend, -dontbother, strbeg) - 1;
2682 /* for multiline we only have to try after newlines */
2683 if (prog->check_substr || prog->check_utf8) {
2684 /* because of the goto we can not easily reuse the macros for bifurcating the
2685 unicode/non-unicode match modes here like we do elsewhere - demerphq */
2688 goto after_try_utf8;
2690 if (regtry(reginfo, &s)) {
2697 if (prog->extflags & RXf_USE_INTUIT) {
2698 s = re_intuit_start(rx, sv, strbeg,
2699 s + UTF8SKIP(s), strend, flags, NULL);
2708 } /* end search for check string in unicode */
2710 if (s == startpos) {
2711 goto after_try_latin;
2714 if (regtry(reginfo, &s)) {
2721 if (prog->extflags & RXf_USE_INTUIT) {
2722 s = re_intuit_start(rx, sv, strbeg,
2723 s + 1, strend, flags, NULL);
2732 } /* end search for check string in latin*/
2733 } /* end search for check string */
2734 else { /* search for newline */
2736 /*XXX: The s-- is almost definitely wrong here under unicode - demeprhq*/
2739 /* We can use a more efficient search as newlines are the same in unicode as they are in latin */
2740 while (s <= end) { /* note it could be possible to match at the end of the string */
2741 if (*s++ == '\n') { /* don't need PL_utf8skip here */
2742 if (regtry(reginfo, &s))
2746 } /* end search for newline */
2747 } /* end anchored/multiline check string search */
2749 } else if (prog->intflags & PREGf_ANCH_GPOS)
2751 /* PREGf_ANCH_GPOS should never be true if PREGf_GPOS_SEEN is not true */
2752 assert(prog->intflags & PREGf_GPOS_SEEN);
2753 /* For anchored \G, the only position it can match from is
2754 * (ganch-gofs); we already set startpos to this above; if intuit
2755 * moved us on from there, we can't possibly succeed */
2756 assert(startpos == reginfo->ganch - prog->gofs);
2757 if (s == startpos && regtry(reginfo, &s))
2762 /* Messy cases: unanchored match. */
2763 if ((prog->anchored_substr || prog->anchored_utf8) && prog->intflags & PREGf_SKIP) {
2764 /* we have /x+whatever/ */
2765 /* it must be a one character string (XXXX Except is_utf8_pat?) */
2771 if (! prog->anchored_utf8) {
2772 to_utf8_substr(prog);
2774 ch = SvPVX_const(prog->anchored_utf8)[0];
2777 DEBUG_EXECUTE_r( did_match = 1 );
2778 if (regtry(reginfo, &s)) goto got_it;
2780 while (s < strend && *s == ch)
2787 if (! prog->anchored_substr) {
2788 if (! to_byte_substr(prog)) {
2789 NON_UTF8_TARGET_BUT_UTF8_REQUIRED(phooey);
2792 ch = SvPVX_const(prog->anchored_substr)[0];
2795 DEBUG_EXECUTE_r( did_match = 1 );
2796 if (regtry(reginfo, &s)) goto got_it;
2798 while (s < strend && *s == ch)
2803 DEBUG_EXECUTE_r(if (!did_match)
2804 PerlIO_printf(Perl_debug_log,
2805 "Did not find anchored character...\n")
2808 else if (prog->anchored_substr != NULL
2809 || prog->anchored_utf8 != NULL
2810 || ((prog->float_substr != NULL || prog->float_utf8 != NULL)
2811 && prog->float_max_offset < strend - s)) {
2816 char *last1; /* Last position checked before */
2820 if (prog->anchored_substr || prog->anchored_utf8) {
2822 if (! prog->anchored_utf8) {
2823 to_utf8_substr(prog);
2825 must = prog->anchored_utf8;
2828 if (! prog->anchored_substr) {
2829 if (! to_byte_substr(prog)) {
2830 NON_UTF8_TARGET_BUT_UTF8_REQUIRED(phooey);
2833 must = prog->anchored_substr;
2835 back_max = back_min = prog->anchored_offset;
2838 if (! prog->float_utf8) {
2839 to_utf8_substr(prog);
2841 must = prog->float_utf8;
2844 if (! prog->float_substr) {
2845 if (! to_byte_substr(prog)) {
2846 NON_UTF8_TARGET_BUT_UTF8_REQUIRED(phooey);
2849 must = prog->float_substr;
2851 back_max = prog->float_max_offset;
2852 back_min = prog->float_min_offset;
2858 last = HOP3c(strend, /* Cannot start after this */
2859 -(SSize_t)(CHR_SVLEN(must)
2860 - (SvTAIL(must) != 0) + back_min), strbeg);
2862 if (s > reginfo->strbeg)
2863 last1 = HOPc(s, -1);
2865 last1 = s - 1; /* bogus */
2867 /* XXXX check_substr already used to find "s", can optimize if
2868 check_substr==must. */
2870 strend = HOPc(strend, -dontbother);
2871 while ( (s <= last) &&
2872 (s = fbm_instr((unsigned char*)HOP4c(s, back_min, strbeg, strend),
2873 (unsigned char*)strend, must,
2874 multiline ? FBMrf_MULTILINE : 0)) ) {
2875 DEBUG_EXECUTE_r( did_match = 1 );
2876 if (HOPc(s, -back_max) > last1) {
2877 last1 = HOPc(s, -back_min);
2878 s = HOPc(s, -back_max);
2881 char * const t = (last1 >= reginfo->strbeg)
2882 ? HOPc(last1, 1) : last1 + 1;
2884 last1 = HOPc(s, -back_min);
2888 while (s <= last1) {
2889 if (regtry(reginfo, &s))
2892 s++; /* to break out of outer loop */
2899 while (s <= last1) {
2900 if (regtry(reginfo, &s))
2906 DEBUG_EXECUTE_r(if (!did_match) {
2907 RE_PV_QUOTED_DECL(quoted, utf8_target, PERL_DEBUG_PAD_ZERO(0),
2908 SvPVX_const(must), RE_SV_DUMPLEN(must), 30);
2909 PerlIO_printf(Perl_debug_log, "Did not find %s substr %s%s...\n",
2910 ((must == prog->anchored_substr || must == prog->anchored_utf8)
2911 ? "anchored" : "floating"),
2912 quoted, RE_SV_TAIL(must));
2916 else if ( (c = progi->regstclass) ) {
2918 const OPCODE op = OP(progi->regstclass);
2919 /* don't bother with what can't match */
2920 if (PL_regkind[op] != EXACT && op != CANY && PL_regkind[op] != TRIE)
2921 strend = HOPc(strend, -(minlen - 1));
2924 SV * const prop = sv_newmortal();
2925 regprop(prog, prop, c, reginfo);
2927 RE_PV_QUOTED_DECL(quoted,utf8_target,PERL_DEBUG_PAD_ZERO(1),
2929 PerlIO_printf(Perl_debug_log,
2930 "Matching stclass %.*s against %s (%d bytes)\n",
2931 (int)SvCUR(prop), SvPVX_const(prop),
2932 quoted, (int)(strend - s));
2935 if (find_byclass(prog, c, s, strend, reginfo))
2937 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log, "Contradicts stclass... [regexec_flags]\n"));
2941 if (prog->float_substr != NULL || prog->float_utf8 != NULL) {
2949 if (! prog->float_utf8) {
2950 to_utf8_substr(prog);
2952 float_real = prog->float_utf8;
2955 if (! prog->float_substr) {
2956 if (! to_byte_substr(prog)) {
2957 NON_UTF8_TARGET_BUT_UTF8_REQUIRED(phooey);
2960 float_real = prog->float_substr;
2963 little = SvPV_const(float_real, len);
2964 if (SvTAIL(float_real)) {
2965 /* This means that float_real contains an artificial \n on
2966 * the end due to the presence of something like this:
2967 * /foo$/ where we can match both "foo" and "foo\n" at the
2968 * end of the string. So we have to compare the end of the
2969 * string first against the float_real without the \n and
2970 * then against the full float_real with the string. We
2971 * have to watch out for cases where the string might be
2972 * smaller than the float_real or the float_real without
2974 char *checkpos= strend - len;
2976 PerlIO_printf(Perl_debug_log,
2977 "%sChecking for float_real.%s\n",
2978 PL_colors[4], PL_colors[5]));
2979 if (checkpos + 1 < strbeg) {
2980 /* can't match, even if we remove the trailing \n
2981 * string is too short to match */
2983 PerlIO_printf(Perl_debug_log,
2984 "%sString shorter than required trailing substring, cannot match.%s\n",
2985 PL_colors[4], PL_colors[5]));
2987 } else if (memEQ(checkpos + 1, little, len - 1)) {
2988 /* can match, the end of the string matches without the
2990 last = checkpos + 1;
2991 } else if (checkpos < strbeg) {
2992 /* cant match, string is too short when the "\n" is
2995 PerlIO_printf(Perl_debug_log,
2996 "%sString does not contain required trailing substring, cannot match.%s\n",
2997 PL_colors[4], PL_colors[5]));
2999 } else if (!multiline) {
3000 /* non multiline match, so compare with the "\n" at the
3001 * end of the string */
3002 if (memEQ(checkpos, little, len)) {
3006 PerlIO_printf(Perl_debug_log,
3007 "%sString does not contain required trailing substring, cannot match.%s\n",
3008 PL_colors[4], PL_colors[5]));
3012 /* multiline match, so we have to search for a place
3013 * where the full string is located */
3019 last = rninstr(s, strend, little, little + len);
3021 last = strend; /* matching "$" */
3024 /* at one point this block contained a comment which was
3025 * probably incorrect, which said that this was a "should not
3026 * happen" case. Even if it was true when it was written I am
3027 * pretty sure it is not anymore, so I have removed the comment
3028 * and replaced it with this one. Yves */
3030 PerlIO_printf(Perl_debug_log,
3031 "String does not contain required substring, cannot match.\n"
3035 dontbother = strend - last + prog->float_min_offset;
3037 if (minlen && (dontbother < minlen))
3038 dontbother = minlen - 1;
3039 strend -= dontbother; /* this one's always in bytes! */
3040 /* We don't know much -- general case. */
3043 if (regtry(reginfo, &s))
3052 if (regtry(reginfo, &s))
3054 } while (s++ < strend);
3062 /* s/// doesn't like it if $& is earlier than where we asked it to
3063 * start searching (which can happen on something like /.\G/) */
3064 if ( (flags & REXEC_FAIL_ON_UNDERFLOW)
3065 && (prog->offs[0].start < stringarg - strbeg))
3067 /* this should only be possible under \G */
3068 assert(prog->intflags & PREGf_GPOS_SEEN);
3069 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
3070 "matched, but failing for REXEC_FAIL_ON_UNDERFLOW\n"));
3076 PerlIO_printf(Perl_debug_log,
3077 "rex=0x%"UVxf" freeing offs: 0x%"UVxf"\n",
3084 /* clean up; this will trigger destructors that will free all slabs
3085 * above the current one, and cleanup the regmatch_info_aux
3086 * and regmatch_info_aux_eval sructs */
3088 LEAVE_SCOPE(oldsave);
3090 if (RXp_PAREN_NAMES(prog))
3091 (void)hv_iterinit(RXp_PAREN_NAMES(prog));
3093 RX_MATCH_UTF8_set(rx, utf8_target);
3095 /* make sure $`, $&, $', and $digit will work later */
3096 if ( !(flags & REXEC_NOT_FIRST) )
3097 S_reg_set_capture_string(aTHX_ rx,
3098 strbeg, reginfo->strend,
3099 sv, flags, utf8_target);
3104 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log, "%sMatch failed%s\n",
3105 PL_colors[4], PL_colors[5]));
3107 /* clean up; this will trigger destructors that will free all slabs
3108 * above the current one, and cleanup the regmatch_info_aux
3109 * and regmatch_info_aux_eval sructs */
3111 LEAVE_SCOPE(oldsave);
3114 /* we failed :-( roll it back */
3115 DEBUG_BUFFERS_r(PerlIO_printf(Perl_debug_log,
3116 "rex=0x%"UVxf" rolling back offs: freeing=0x%"UVxf" restoring=0x%"UVxf"\n",
3121 Safefree(prog->offs);
3128 /* Set which rex is pointed to by PL_reg_curpm, handling ref counting.
3129 * Do inc before dec, in case old and new rex are the same */
3130 #define SET_reg_curpm(Re2) \
3131 if (reginfo->info_aux_eval) { \
3132 (void)ReREFCNT_inc(Re2); \
3133 ReREFCNT_dec(PM_GETRE(PL_reg_curpm)); \
3134 PM_SETRE((PL_reg_curpm), (Re2)); \
3139 - regtry - try match at specific point
3141 STATIC I32 /* 0 failure, 1 success */
3142 S_regtry(pTHX_ regmatch_info *reginfo, char **startposp)
3145 REGEXP *const rx = reginfo->prog;
3146 regexp *const prog = ReANY(rx);
3148 RXi_GET_DECL(prog,progi);
3149 GET_RE_DEBUG_FLAGS_DECL;
3151 PERL_ARGS_ASSERT_REGTRY;
3153 reginfo->cutpoint=NULL;
3155 prog->offs[0].start = *startposp - reginfo->strbeg;
3156 prog->lastparen = 0;
3157 prog->lastcloseparen = 0;
3159 /* XXXX What this code is doing here?!!! There should be no need
3160 to do this again and again, prog->lastparen should take care of
3163 /* Tests pat.t#187 and split.t#{13,14} seem to depend on this code.
3164 * Actually, the code in regcppop() (which Ilya may be meaning by
3165 * prog->lastparen), is not needed at all by the test suite
3166 * (op/regexp, op/pat, op/split), but that code is needed otherwise
3167 * this erroneously leaves $1 defined: "1" =~ /^(?:(\d)x)?\d$/
3168 * Meanwhile, this code *is* needed for the
3169 * above-mentioned test suite tests to succeed. The common theme
3170 * on those tests seems to be returning null fields from matches.
3171 * --jhi updated by dapm */
3173 if (prog->nparens) {
3174 regexp_paren_pair *pp = prog->offs;
3176 for (i = prog->nparens; i > (I32)prog->lastparen; i--) {
3184 result = regmatch(reginfo, *startposp, progi->program + 1);
3186 prog->offs[0].end = result;
3189 if (reginfo->cutpoint)
3190 *startposp= reginfo->cutpoint;
3191 REGCP_UNWIND(lastcp);
3196 #define sayYES goto yes
3197 #define sayNO goto no
3198 #define sayNO_SILENT goto no_silent
3200 /* we dont use STMT_START/END here because it leads to
3201 "unreachable code" warnings, which are bogus, but distracting. */
3202 #define CACHEsayNO \
3203 if (ST.cache_mask) \
3204 reginfo->info_aux->poscache[ST.cache_offset] |= ST.cache_mask; \
3207 /* this is used to determine how far from the left messages like
3208 'failed...' are printed. It should be set such that messages
3209 are inline with the regop output that created them.
3211 #define REPORT_CODE_OFF 32
3214 #define CHRTEST_UNINIT -1001 /* c1/c2 haven't been calculated yet */
3215 #define CHRTEST_VOID -1000 /* the c1/c2 "next char" test should be skipped */
3216 #define CHRTEST_NOT_A_CP_1 -999
3217 #define CHRTEST_NOT_A_CP_2 -998
3219 /* grab a new slab and return the first slot in it */
3221 STATIC regmatch_state *
3224 #if PERL_VERSION < 9 && !defined(PERL_CORE)
3227 regmatch_slab *s = PL_regmatch_slab->next;
3229 Newx(s, 1, regmatch_slab);
3230 s->prev = PL_regmatch_slab;
3232 PL_regmatch_slab->next = s;
3234 PL_regmatch_slab = s;
3235 return SLAB_FIRST(s);
3239 /* push a new state then goto it */
3241 #define PUSH_STATE_GOTO(state, node, input) \
3242 pushinput = input; \
3244 st->resume_state = state; \
3247 /* push a new state with success backtracking, then goto it */
3249 #define PUSH_YES_STATE_GOTO(state, node, input) \
3250 pushinput = input; \
3252 st->resume_state = state; \
3253 goto push_yes_state;
3260 regmatch() - main matching routine
3262 This is basically one big switch statement in a loop. We execute an op,
3263 set 'next' to point the next op, and continue. If we come to a point which
3264 we may need to backtrack to on failure such as (A|B|C), we push a
3265 backtrack state onto the backtrack stack. On failure, we pop the top
3266 state, and re-enter the loop at the state indicated. If there are no more
3267 states to pop, we return failure.
3269 Sometimes we also need to backtrack on success; for example /A+/, where
3270 after successfully matching one A, we need to go back and try to
3271 match another one; similarly for lookahead assertions: if the assertion
3272 completes successfully, we backtrack to the state just before the assertion
3273 and then carry on. In these cases, the pushed state is marked as
3274 'backtrack on success too'. This marking is in fact done by a chain of
3275 pointers, each pointing to the previous 'yes' state. On success, we pop to
3276 the nearest yes state, discarding any intermediate failure-only states.
3277 Sometimes a yes state is pushed just to force some cleanup code to be
3278 called at the end of a successful match or submatch; e.g. (??{$re}) uses
3279 it to free the inner regex.
3281 Note that failure backtracking rewinds the cursor position, while
3282 success backtracking leaves it alone.
3284 A pattern is complete when the END op is executed, while a subpattern
3285 such as (?=foo) is complete when the SUCCESS op is executed. Both of these
3286 ops trigger the "pop to last yes state if any, otherwise return true"
3289 A common convention in this function is to use A and B to refer to the two
3290 subpatterns (or to the first nodes thereof) in patterns like /A*B/: so A is
3291 the subpattern to be matched possibly multiple times, while B is the entire
3292 rest of the pattern. Variable and state names reflect this convention.
3294 The states in the main switch are the union of ops and failure/success of
3295 substates associated with with that op. For example, IFMATCH is the op
3296 that does lookahead assertions /(?=A)B/ and so the IFMATCH state means
3297 'execute IFMATCH'; while IFMATCH_A is a state saying that we have just
3298 successfully matched A and IFMATCH_A_fail is a state saying that we have
3299 just failed to match A. Resume states always come in pairs. The backtrack
3300 state we push is marked as 'IFMATCH_A', but when that is popped, we resume
3301 at IFMATCH_A or IFMATCH_A_fail, depending on whether we are backtracking
3302 on success or failure.
3304 The struct that holds a backtracking state is actually a big union, with
3305 one variant for each major type of op. The variable st points to the
3306 top-most backtrack struct. To make the code clearer, within each
3307 block of code we #define ST to alias the relevant union.
3309 Here's a concrete example of a (vastly oversimplified) IFMATCH
3315 #define ST st->u.ifmatch
3317 case IFMATCH: // we are executing the IFMATCH op, (?=A)B
3318 ST.foo = ...; // some state we wish to save
3320 // push a yes backtrack state with a resume value of
3321 // IFMATCH_A/IFMATCH_A_fail, then continue execution at the
3323 PUSH_YES_STATE_GOTO(IFMATCH_A, A, newinput);
3326 case IFMATCH_A: // we have successfully executed A; now continue with B
3328 bar = ST.foo; // do something with the preserved value
3331 case IFMATCH_A_fail: // A failed, so the assertion failed
3332 ...; // do some housekeeping, then ...
3333 sayNO; // propagate the failure
3340 For any old-timers reading this who are familiar with the old recursive
3341 approach, the code above is equivalent to:
3343 case IFMATCH: // we are executing the IFMATCH op, (?=A)B
3352 ...; // do some housekeeping, then ...
3353 sayNO; // propagate the failure
3356 The topmost backtrack state, pointed to by st, is usually free. If you
3357 want to claim it, populate any ST.foo fields in it with values you wish to
3358 save, then do one of
3360 PUSH_STATE_GOTO(resume_state, node, newinput);
3361 PUSH_YES_STATE_GOTO(resume_state, node, newinput);
3363 which sets that backtrack state's resume value to 'resume_state', pushes a
3364 new free entry to the top of the backtrack stack, then goes to 'node'.
3365 On backtracking, the free slot is popped, and the saved state becomes the
3366 new free state. An ST.foo field in this new top state can be temporarily
3367 accessed to retrieve values, but once the main loop is re-entered, it
3368 becomes available for reuse.
3370 Note that the depth of the backtrack stack constantly increases during the
3371 left-to-right execution of the pattern, rather than going up and down with
3372 the pattern nesting. For example the stack is at its maximum at Z at the
3373 end of the pattern, rather than at X in the following:
3375 /(((X)+)+)+....(Y)+....Z/
3377 The only exceptions to this are lookahead/behind assertions and the cut,
3378 (?>A), which pop all the backtrack states associated with A before
3381 Backtrack state structs are allocated in slabs of about 4K in size.
3382 PL_regmatch_state and st always point to the currently active state,
3383 and PL_regmatch_slab points to the slab currently containing
3384 PL_regmatch_state. The first time regmatch() is called, the first slab is
3385 allocated, and is never freed until interpreter destruction. When the slab
3386 is full, a new one is allocated and chained to the end. At exit from
3387 regmatch(), slabs allocated since entry are freed.
3392 #define DEBUG_STATE_pp(pp) \
3394 DUMP_EXEC_POS(locinput, scan, utf8_target); \
3395 PerlIO_printf(Perl_debug_log, \
3396 " %*s"pp" %s%s%s%s%s\n", \
3398 PL_reg_name[st->resume_state], \
3399 ((st==yes_state||st==mark_state) ? "[" : ""), \
3400 ((st==yes_state) ? "Y" : ""), \
3401 ((st==mark_state) ? "M" : ""), \
3402 ((st==yes_state||st==mark_state) ? "]" : "") \
3407 #define REG_NODE_NUM(x) ((x) ? (int)((x)-prog) : -1)
3412 S_debug_start_match(pTHX_ const REGEXP *prog, const bool utf8_target,
3413 const char *start, const char *end, const char *blurb)
3415 const bool utf8_pat = RX_UTF8(prog) ? 1 : 0;
3417 PERL_ARGS_ASSERT_DEBUG_START_MATCH;
3422 RE_PV_QUOTED_DECL(s0, utf8_pat, PERL_DEBUG_PAD_ZERO(0),
3423 RX_PRECOMP_const(prog), RX_PRELEN(prog), 60);
3425 RE_PV_QUOTED_DECL(s1, utf8_target, PERL_DEBUG_PAD_ZERO(1),
3426 start, end - start, 60);
3428 PerlIO_printf(Perl_debug_log,
3429 "%s%s REx%s %s against %s\n",
3430 PL_colors[4], blurb, PL_colors[5], s0, s1);
3432 if (utf8_target||utf8_pat)
3433 PerlIO_printf(Perl_debug_log, "UTF-8 %s%s%s...\n",
3434 utf8_pat ? "pattern" : "",
3435 utf8_pat && utf8_target ? " and " : "",
3436 utf8_target ? "string" : ""
3442 S_dump_exec_pos(pTHX_ const char *locinput,
3443 const regnode *scan,
3444 const char *loc_regeol,
3445 const char *loc_bostr,
3446 const char *loc_reg_starttry,
3447 const bool utf8_target)
3449 const int docolor = *PL_colors[0] || *PL_colors[2] || *PL_colors[4];
3450 const int taill = (docolor ? 10 : 7); /* 3 chars for "> <" */
3451 int l = (loc_regeol - locinput) > taill ? taill : (loc_regeol - locinput);
3452 /* The part of the string before starttry has one color
3453 (pref0_len chars), between starttry and current
3454 position another one (pref_len - pref0_len chars),
3455 after the current position the third one.
3456 We assume that pref0_len <= pref_len, otherwise we
3457 decrease pref0_len. */
3458 int pref_len = (locinput - loc_bostr) > (5 + taill) - l
3459 ? (5 + taill) - l : locinput - loc_bostr;
3462 PERL_ARGS_ASSERT_DUMP_EXEC_POS;
3464 while (utf8_target && UTF8_IS_CONTINUATION(*(U8*)(locinput - pref_len)))
3466 pref0_len = pref_len - (locinput - loc_reg_starttry);
3467 if (l + pref_len < (5 + taill) && l < loc_regeol - locinput)
3468 l = ( loc_regeol - locinput > (5 + taill) - pref_len
3469 ? (5 + taill) - pref_len : loc_regeol - locinput);
3470 while (utf8_target && UTF8_IS_CONTINUATION(*(U8*)(locinput + l)))
3474 if (pref0_len > pref_len)
3475 pref0_len = pref_len;
3477 const int is_uni = (utf8_target && OP(scan) != CANY) ? 1 : 0;
3479 RE_PV_COLOR_DECL(s0,len0,is_uni,PERL_DEBUG_PAD(0),
3480 (locinput - pref_len),pref0_len, 60, 4, 5);
3482 RE_PV_COLOR_DECL(s1,len1,is_uni,PERL_DEBUG_PAD(1),
3483 (locinput - pref_len + pref0_len),
3484 pref_len - pref0_len, 60, 2, 3);
3486 RE_PV_COLOR_DECL(s2,len2,is_uni,PERL_DEBUG_PAD(2),
3487 locinput, loc_regeol - locinput, 10, 0, 1);
3489 const STRLEN tlen=len0+len1+len2;
3490 PerlIO_printf(Perl_debug_log,
3491 "%4"IVdf" <%.*s%.*s%s%.*s>%*s|",
3492 (IV)(locinput - loc_bostr),
3495 (docolor ? "" : "> <"),
3497 (int)(tlen > 19 ? 0 : 19 - tlen),
3504 /* reg_check_named_buff_matched()
3505 * Checks to see if a named buffer has matched. The data array of
3506 * buffer numbers corresponding to the buffer is expected to reside
3507 * in the regexp->data->data array in the slot stored in the ARG() of
3508 * node involved. Note that this routine doesn't actually care about the
3509 * name, that information is not preserved from compilation to execution.
3510 * Returns the index of the leftmost defined buffer with the given name
3511 * or 0 if non of the buffers matched.
3514 S_reg_check_named_buff_matched(const regexp *rex, const regnode *scan)
3517 RXi_GET_DECL(rex,rexi);
3518 SV *sv_dat= MUTABLE_SV(rexi->data->data[ ARG( scan ) ]);
3519 I32 *nums=(I32*)SvPVX(sv_dat);
3521 PERL_ARGS_ASSERT_REG_CHECK_NAMED_BUFF_MATCHED;
3523 for ( n=0; n<SvIVX(sv_dat); n++ ) {
3524 if ((I32)rex->lastparen >= nums[n] &&
3525 rex->offs[nums[n]].end != -1)
3535 S_setup_EXACTISH_ST_c1_c2(pTHX_ const regnode * const text_node, int *c1p,
3536 U8* c1_utf8, int *c2p, U8* c2_utf8, regmatch_info *reginfo)
3538 /* This function determines if there are one or two characters that match
3539 * the first character of the passed-in EXACTish node <text_node>, and if
3540 * so, returns them in the passed-in pointers.
3542 * If it determines that no possible character in the target string can
3543 * match, it returns FALSE; otherwise TRUE. (The FALSE situation occurs if
3544 * the first character in <text_node> requires UTF-8 to represent, and the
3545 * target string isn't in UTF-8.)
3547 * If there are more than two characters that could match the beginning of
3548 * <text_node>, or if more context is required to determine a match or not,
3549 * it sets both *<c1p> and *<c2p> to CHRTEST_VOID.
3551 * The motiviation behind this function is to allow the caller to set up
3552 * tight loops for matching. If <text_node> is of type EXACT, there is
3553 * only one possible character that can match its first character, and so
3554 * the situation is quite simple. But things get much more complicated if
3555 * folding is involved. It may be that the first character of an EXACTFish
3556 * node doesn't participate in any possible fold, e.g., punctuation, so it
3557 * can be matched only by itself. The vast majority of characters that are
3558 * in folds match just two things, their lower and upper-case equivalents.
3559 * But not all are like that; some have multiple possible matches, or match
3560 * sequences of more than one character. This function sorts all that out.
3562 * Consider the patterns A*B or A*?B where A and B are arbitrary. In a
3563 * loop of trying to match A*, we know we can't exit where the thing
3564 * following it isn't a B. And something can't be a B unless it is the
3565 * beginning of B. By putting a quick test for that beginning in a tight
3566 * loop, we can rule out things that can't possibly be B without having to
3567 * break out of the loop, thus avoiding work. Similarly, if A is a single
3568 * character, we can make a tight loop matching A*, using the outputs of
3571 * If the target string to match isn't in UTF-8, and there aren't
3572 * complications which require CHRTEST_VOID, *<c1p> and *<c2p> are set to
3573 * the one or two possible octets (which are characters in this situation)
3574 * that can match. In all cases, if there is only one character that can
3575 * match, *<c1p> and *<c2p> will be identical.
3577 * If the target string is in UTF-8, the buffers pointed to by <c1_utf8>
3578 * and <c2_utf8> will contain the one or two UTF-8 sequences of bytes that
3579 * can match the beginning of <text_node>. They should be declared with at
3580 * least length UTF8_MAXBYTES+1. (If the target string isn't in UTF-8, it is
3581 * undefined what these contain.) If one or both of the buffers are
3582 * invariant under UTF-8, *<c1p>, and *<c2p> will also be set to the
3583 * corresponding invariant. If variant, the corresponding *<c1p> and/or
3584 * *<c2p> will be set to a negative number(s) that shouldn't match any code
3585 * point (unless inappropriately coerced to unsigned). *<c1p> will equal
3586 * *<c2p> if and only if <c1_utf8> and <c2_utf8> are the same. */
3588 const bool utf8_target = reginfo->is_utf8_target;
3590 UV c1 = CHRTEST_NOT_A_CP_1;
3591 UV c2 = CHRTEST_NOT_A_CP_2;
3592 bool use_chrtest_void = FALSE;
3593 const bool is_utf8_pat = reginfo->is_utf8_pat;
3595 /* Used when we have both utf8 input and utf8 output, to avoid converting
3596 * to/from code points */
3597 bool utf8_has_been_setup = FALSE;
3601 U8 *pat = (U8*)STRING(text_node);
3602 U8 folded[UTF8_MAX_FOLD_CHAR_EXPAND * UTF8_MAXBYTES_CASE + 1] = { '\0' };
3604 if (OP(text_node) == EXACT) {
3606 /* In an exact node, only one thing can be matched, that first
3607 * character. If both the pat and the target are UTF-8, we can just
3608 * copy the input to the output, avoiding finding the code point of
3613 else if (utf8_target) {
3614 Copy(pat, c1_utf8, UTF8SKIP(pat), U8);
3615 Copy(pat, c2_utf8, UTF8SKIP(pat), U8);
3616 utf8_has_been_setup = TRUE;
3619 c2 = c1 = valid_utf8_to_uvchr(pat, NULL);
3622 else { /* an EXACTFish node */
3623 U8 *pat_end = pat + STR_LEN(text_node);
3625 /* An EXACTFL node has at least some characters unfolded, because what
3626 * they match is not known until now. So, now is the time to fold
3627 * the first few of them, as many as are needed to determine 'c1' and
3628 * 'c2' later in the routine. If the pattern isn't UTF-8, we only need
3629 * to fold if in a UTF-8 locale, and then only the Sharp S; everything
3630 * else is 1-1 and isn't assumed to be folded. In a UTF-8 pattern, we
3631 * need to fold as many characters as a single character can fold to,
3632 * so that later we can check if the first ones are such a multi-char
3633 * fold. But, in such a pattern only locale-problematic characters
3634 * aren't folded, so we can skip this completely if the first character
3635 * in the node isn't one of the tricky ones */
3636 if (OP(text_node) == EXACTFL) {
3638 if (! is_utf8_pat) {
3639 if (IN_UTF8_CTYPE_LOCALE && *pat == LATIN_SMALL_LETTER_SHARP_S)
3641 folded[0] = folded[1] = 's';
3643 pat_end = folded + 2;
3646 else if (is_PROBLEMATIC_LOCALE_FOLDEDS_START_utf8(pat)) {
3651 for (i = 0; i < UTF8_MAX_FOLD_CHAR_EXPAND && s < pat_end; i++) {
3653 *(d++) = (U8) toFOLD_LC(*s);
3658 _to_utf8_fold_flags(s,
3661 FOLD_FLAGS_FULL | FOLD_FLAGS_LOCALE);
3672 if ((is_utf8_pat && is_MULTI_CHAR_FOLD_utf8_safe(pat, pat_end))
3673 || (!is_utf8_pat && is_MULTI_CHAR_FOLD_latin1_safe(pat, pat_end)))
3675 /* Multi-character folds require more context to sort out. Also
3676 * PL_utf8_foldclosures used below doesn't handle them, so have to
3677 * be handled outside this routine */
3678 use_chrtest_void = TRUE;
3680 else { /* an EXACTFish node which doesn't begin with a multi-char fold */
3681 c1 = is_utf8_pat ? valid_utf8_to_uvchr(pat, NULL) : *pat;
3683 /* Load the folds hash, if not already done */
3685 if (! PL_utf8_foldclosures) {
3686 _load_PL_utf8_foldclosures();
3689 /* The fold closures data structure is a hash with the keys
3690 * being the UTF-8 of every character that is folded to, like
3691 * 'k', and the values each an array of all code points that
3692 * fold to its key. e.g. [ 'k', 'K', KELVIN_SIGN ].
3693 * Multi-character folds are not included */
3694 if ((! (listp = hv_fetch(PL_utf8_foldclosures,
3699 /* Not found in the hash, therefore there are no folds
3700 * containing it, so there is only a single character that
3704 else { /* Does participate in folds */
3705 AV* list = (AV*) *listp;
3706 if (av_tindex(list) != 1) {
3708 /* If there aren't exactly two folds to this, it is
3709 * outside the scope of this function */
3710 use_chrtest_void = TRUE;
3712 else { /* There are two. Get them */
3713 SV** c_p = av_fetch(list, 0, FALSE);
3715 Perl_croak(aTHX_ "panic: invalid PL_utf8_foldclosures structure");
3719 c_p = av_fetch(list, 1, FALSE);
3721 Perl_croak(aTHX_ "panic: invalid PL_utf8_foldclosures structure");
3725 /* Folds that cross the 255/256 boundary are forbidden
3726 * if EXACTFL (and isnt a UTF8 locale), or EXACTFA and
3727 * one is ASCIII. Since the pattern character is above
3728 * 255, and its only other match is below 256, the only
3729 * legal match will be to itself. We have thrown away
3730 * the original, so have to compute which is the one
3732 if ((c1 < 256) != (c2 < 256)) {
3733 if ((OP(text_node) == EXACTFL
3734 && ! IN_UTF8_CTYPE_LOCALE)
3735 || ((OP(text_node) == EXACTFA
3736 || OP(text_node) == EXACTFA_NO_TRIE)
3737 && (isASCII(c1) || isASCII(c2))))
3750 else /* Here, c1 is <= 255 */
3752 && HAS_NONLATIN1_FOLD_CLOSURE(c1)
3753 && ( ! (OP(text_node) == EXACTFL && ! IN_UTF8_CTYPE_LOCALE))
3754 && ((OP(text_node) != EXACTFA
3755 && OP(text_node) != EXACTFA_NO_TRIE)
3758 /* Here, there could be something above Latin1 in the target
3759 * which folds to this character in the pattern. All such
3760 * cases except LATIN SMALL LETTER Y WITH DIAERESIS have more
3761 * than two characters involved in their folds, so are outside
3762 * the scope of this function */
3763 if (UNLIKELY(c1 == LATIN_SMALL_LETTER_Y_WITH_DIAERESIS)) {
3764 c2 = LATIN_CAPITAL_LETTER_Y_WITH_DIAERESIS;
3767 use_chrtest_void = TRUE;
3770 else { /* Here nothing above Latin1 can fold to the pattern
3772 switch (OP(text_node)) {
3774 case EXACTFL: /* /l rules */
3775 c2 = PL_fold_locale[c1];
3778 case EXACTF: /* This node only generated for non-utf8
3780 assert(! is_utf8_pat);
3781 if (! utf8_target) { /* /d rules */
3786 /* /u rules for all these. This happens to work for
3787 * EXACTFA as nothing in Latin1 folds to ASCII */
3788 case EXACTFA_NO_TRIE: /* This node only generated for
3789 non-utf8 patterns */
3790 assert(! is_utf8_pat);
3795 c2 = PL_fold_latin1[c1];
3799 Perl_croak(aTHX_ "panic: Unexpected op %u", OP(text_node));
3800 assert(0); /* NOTREACHED */
3806 /* Here have figured things out. Set up the returns */
3807 if (use_chrtest_void) {
3808 *c2p = *c1p = CHRTEST_VOID;
3810 else if (utf8_target) {
3811 if (! utf8_has_been_setup) { /* Don't have the utf8; must get it */
3812 uvchr_to_utf8(c1_utf8, c1);
3813 uvchr_to_utf8(c2_utf8, c2);
3816 /* Invariants are stored in both the utf8 and byte outputs; Use
3817 * negative numbers otherwise for the byte ones. Make sure that the
3818 * byte ones are the same iff the utf8 ones are the same */
3819 *c1p = (UTF8_IS_INVARIANT(*c1_utf8)) ? *c1_utf8 : CHRTEST_NOT_A_CP_1;
3820 *c2p = (UTF8_IS_INVARIANT(*c2_utf8))
3823 ? CHRTEST_NOT_A_CP_1
3824 : CHRTEST_NOT_A_CP_2;
3826 else if (c1 > 255) {
3827 if (c2 > 255) { /* both possibilities are above what a non-utf8 string
3832 *c1p = *c2p = c2; /* c2 is the only representable value */
3834 else { /* c1 is representable; see about c2 */
3836 *c2p = (c2 < 256) ? c2 : c1;
3842 /* returns -1 on failure, $+[0] on success */
3844 S_regmatch(pTHX_ regmatch_info *reginfo, char *startpos, regnode *prog)
3846 #if PERL_VERSION < 9 && !defined(PERL_CORE)
3850 const bool utf8_target = reginfo->is_utf8_target;
3851 const U32 uniflags = UTF8_ALLOW_DEFAULT;
3852 REGEXP *rex_sv = reginfo->prog;
3853 regexp *rex = ReANY(rex_sv);
3854 RXi_GET_DECL(rex,rexi);
3855 /* the current state. This is a cached copy of PL_regmatch_state */
3857 /* cache heavy used fields of st in registers */
3860 U32 n = 0; /* general value; init to avoid compiler warning */
3861 SSize_t ln = 0; /* len or last; init to avoid compiler warning */
3862 char *locinput = startpos;
3863 char *pushinput; /* where to continue after a PUSH */
3864 I32 nextchr; /* is always set to UCHARAT(locinput) */
3866 bool result = 0; /* return value of S_regmatch */
3867 int depth = 0; /* depth of backtrack stack */
3868 U32 nochange_depth = 0; /* depth of GOSUB recursion with nochange */
3869 const U32 max_nochange_depth =
3870 (3 * rex->nparens > MAX_RECURSE_EVAL_NOCHANGE_DEPTH) ?
3871 3 * rex->nparens : MAX_RECURSE_EVAL_NOCHANGE_DEPTH;
3872 regmatch_state *yes_state = NULL; /* state to pop to on success of
3874 /* mark_state piggy backs on the yes_state logic so that when we unwind
3875 the stack on success we can update the mark_state as we go */
3876 regmatch_state *mark_state = NULL; /* last mark state we have seen */
3877 regmatch_state *cur_eval = NULL; /* most recent EVAL_AB state */
3878 struct regmatch_state *cur_curlyx = NULL; /* most recent curlyx */
3880 bool no_final = 0; /* prevent failure from backtracking? */
3881 bool do_cutgroup = 0; /* no_final only until next branch/trie entry */
3882 char *startpoint = locinput;
3883 SV *popmark = NULL; /* are we looking for a mark? */
3884 SV *sv_commit = NULL; /* last mark name seen in failure */
3885 SV *sv_yes_mark = NULL; /* last mark name we have seen
3886 during a successful match */
3887 U32 lastopen = 0; /* last open we saw */
3888 bool has_cutgroup = RX_HAS_CUTGROUP(rex) ? 1 : 0;
3889 SV* const oreplsv = GvSVn(PL_replgv);
3890 /* these three flags are set by various ops to signal information to
3891 * the very next op. They have a useful lifetime of exactly one loop
3892 * iteration, and are not preserved or restored by state pushes/pops
3894 bool sw = 0; /* the condition value in (?(cond)a|b) */
3895 bool minmod = 0; /* the next "{n,m}" is a "{n,m}?" */
3896 int logical = 0; /* the following EVAL is:
3900 or the following IFMATCH/UNLESSM is:
3901 false: plain (?=foo)
3902 true: used as a condition: (?(?=foo))
3904 PAD* last_pad = NULL;
3906 I32 gimme = G_SCALAR;
3907 CV *caller_cv = NULL; /* who called us */
3908 CV *last_pushed_cv = NULL; /* most recently called (?{}) CV */
3909 CHECKPOINT runops_cp; /* savestack position before executing EVAL */
3910 U32 maxopenparen = 0; /* max '(' index seen so far */
3911 int to_complement; /* Invert the result? */
3912 _char_class_number classnum;
3913 bool is_utf8_pat = reginfo->is_utf8_pat;
3916 GET_RE_DEBUG_FLAGS_DECL;
3919 /* protect against undef(*^R) */
3920 SAVEFREESV(SvREFCNT_inc_simple_NN(oreplsv));
3922 /* shut up 'may be used uninitialized' compiler warnings for dMULTICALL */
3923 multicall_oldcatch = 0;
3924 multicall_cv = NULL;
3926 PERL_UNUSED_VAR(multicall_cop);
3927 PERL_UNUSED_VAR(newsp);
3930 PERL_ARGS_ASSERT_REGMATCH;
3932 DEBUG_OPTIMISE_r( DEBUG_EXECUTE_r({
3933 PerlIO_printf(Perl_debug_log,"regmatch start\n");
3936 st = PL_regmatch_state;
3938 /* Note that nextchr is a byte even in UTF */
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