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Add regex nodes for locale
[perl5.git] / regexec.c
CommitLineData
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1/* regexec.c
2 */
3
4/*
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5 * One Ring to rule them all, One Ring to find them
6 &
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"]
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10 */
11
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12/* This file contains functions for executing a regular expression. See
13 * also regcomp.c which funnily enough, contains functions for compiling
166f8a29 14 * a regular expression.
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15 *
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.
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20 */
21
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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!
24 */
25
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.
29 */
30
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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.
34*/
35
b9d5759e 36#ifdef PERL_EXT_RE_BUILD
54df2634 37#include "re_top.h"
9041c2e3 38#endif
56953603 39
a687059c 40/*
e50aee73 41 * pregcomp and pregexec -- regsub and regerror are not used in perl
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42 *
43 * Copyright (c) 1986 by University of Toronto.
44 * Written by Henry Spencer. Not derived from licensed software.
45 *
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:
49 *
50 * 1. The author is not responsible for the consequences of use of
51 * this software, no matter how awful, even if they arise
52 * from defects in it.
53 *
54 * 2. The origin of this software must not be misrepresented, either
55 * by explicit claim or by omission.
56 *
57 * 3. Altered versions must be plainly marked as such, and must not
58 * be misrepresented as being the original software.
59 *
60 **** Alterations to Henry's code are...
61 ****
4bb101f2 62 **** Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
1129b882
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63 **** 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008
64 **** by Larry Wall and others
a687059c 65 ****
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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.
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68 *
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.
72 */
73#include "EXTERN.h"
864dbfa3 74#define PERL_IN_REGEXEC_C
a687059c 75#include "perl.h"
0f5d15d6 76
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NC
77#ifdef PERL_IN_XSUB_RE
78# include "re_comp.h"
79#else
80# include "regcomp.h"
81#endif
a687059c 82
81e983c1 83#include "inline_invlist.c"
1b0f46bf 84#include "unicode_constants.h"
81e983c1 85
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86#ifdef DEBUGGING
87/* At least one required character in the target string is expressible only in
88 * UTF-8. */
89static const char* const non_utf8_target_but_utf8_required
90 = "Can't match, because target string needs to be in UTF-8\n";
91#endif
92
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));\
95 goto target; \
96} STMT_END
97
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98#define HAS_NONLATIN1_FOLD_CLOSURE(i) _HAS_NONLATIN1_FOLD_CLOSURE_ONLY_FOR_USE_BY_REGCOMP_DOT_C_AND_REGEXEC_DOT_C(i)
99
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100#ifndef STATIC
101#define STATIC static
102#endif
103
2d66f61e 104/* Valid only for non-utf8 strings: avoids the reginclass
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105 * call if there are no complications: i.e., if everything matchable is
106 * straight forward in the bitmap */
3db24e1e 107#define REGINCLASS(prog,p,c) (ANYOF_FLAGS(p) ? reginclass(prog,p,c,c+1,0) \
af364d03 108 : ANYOF_BITMAP_TEST(p,*(c)))
7d3e948e 109
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110/*
111 * Forwards.
112 */
113
f2ed9b32 114#define CHR_SVLEN(sv) (utf8_target ? sv_len_utf8(sv) : SvCUR(sv))
ba44c216 115#define CHR_DIST(a,b) (reginfo->is_utf8_target ? utf8_distance(a,b) : a - b)
a0ed51b3 116
3dab1dad 117#define HOPc(pos,off) \
ba44c216 118 (char *)(reginfo->is_utf8_target \
220db18a 119 ? reghop3((U8*)pos, off, \
9d9163fb 120 (U8*)(off >= 0 ? reginfo->strend : reginfo->strbeg)) \
3dab1dad 121 : (U8*)(pos + off))
557f47af 122
3dab1dad 123#define HOPBACKc(pos, off) \
ba44c216 124 (char*)(reginfo->is_utf8_target \
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125 ? reghopmaybe3((U8*)pos, -off, (U8*)(reginfo->strbeg)) \
126 : (pos - off >= reginfo->strbeg) \
8e11feef 127 ? (U8*)pos - off \
3dab1dad 128 : NULL)
efb30f32 129
ba44c216 130#define HOP3(pos,off,lim) (reginfo->is_utf8_target ? reghop3((U8*)(pos), off, (U8*)(lim)) : (U8*)(pos + off))
1aa99e6b 131#define HOP3c(pos,off,lim) ((char*)HOP3(pos,off,lim))
1aa99e6b 132
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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) \
138 ? (U8*)pos + off \
139 : NULL)
140
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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)))
146
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147#define HOP4(pos,off,llim, rlim) (reginfo->is_utf8_target \
148 ? reghop4((U8*)(pos), off, (U8*)(llim), (U8*)(rlim)) \
149 : (U8*)(pos + off))
150#define HOP4c(pos,off,llim, rlim) ((char*)HOP4(pos,off,llim, rlim))
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151
152#define NEXTCHR_EOS -10 /* nextchr has fallen off the end */
153#define NEXTCHR_IS_EOS (nextchr < 0)
154
155#define SET_nextchr \
220db18a 156 nextchr = ((locinput < reginfo->strend) ? UCHARAT(locinput) : NEXTCHR_EOS)
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DM
157
158#define SET_locinput(p) \
159 locinput = (p); \
160 SET_nextchr
161
162
2a16ac92 163#define LOAD_UTF8_CHARCLASS(swash_ptr, property_name, invlist) STMT_START { \
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164 if (!swash_ptr) { \
165 U8 flags = _CORE_SWASH_INIT_ACCEPT_INVLIST; \
c7304fe2 166 swash_ptr = _core_swash_init("utf8", property_name, &PL_sv_undef, \
2a16ac92 167 1, 0, invlist, &flags); \
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168 assert(swash_ptr); \
169 } \
170 } STMT_END
171
172/* If in debug mode, we test that a known character properly matches */
173#ifdef DEBUGGING
174# define LOAD_UTF8_CHARCLASS_DEBUG_TEST(swash_ptr, \
175 property_name, \
2a16ac92 176 invlist, \
c7304fe2 177 utf8_char_in_property) \
2a16ac92 178 LOAD_UTF8_CHARCLASS(swash_ptr, property_name, invlist); \
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179 assert(swash_fetch(swash_ptr, (U8 *) utf8_char_in_property, TRUE));
180#else
181# define LOAD_UTF8_CHARCLASS_DEBUG_TEST(swash_ptr, \
182 property_name, \
2a16ac92 183 invlist, \
c7304fe2 184 utf8_char_in_property) \
2a16ac92 185 LOAD_UTF8_CHARCLASS(swash_ptr, property_name, invlist)
c7304fe2 186#endif
d1eb3177 187
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188#define LOAD_UTF8_CHARCLASS_ALNUM() LOAD_UTF8_CHARCLASS_DEBUG_TEST( \
189 PL_utf8_swash_ptrs[_CC_WORDCHAR], \
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190 "", \
191 PL_XPosix_ptrs[_CC_WORDCHAR], \
df38da56 192 LATIN_CAPITAL_LETTER_SHARP_S_UTF8);
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193
194#define LOAD_UTF8_CHARCLASS_GCB() /* Grapheme cluster boundaries */ \
195 STMT_START { \
196 LOAD_UTF8_CHARCLASS_DEBUG_TEST(PL_utf8_X_regular_begin, \
197 "_X_regular_begin", \
2a16ac92 198 NULL, \
df38da56 199 LATIN_CAPITAL_LETTER_SHARP_S_UTF8); \
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200 LOAD_UTF8_CHARCLASS_DEBUG_TEST(PL_utf8_X_extend, \
201 "_X_extend", \
2a16ac92 202 NULL, \
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203 COMBINING_GRAVE_ACCENT_UTF8); \
204 } STMT_END
d1eb3177 205
c7304fe2 206#define PLACEHOLDER /* Something for the preprocessor to grab onto */
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207/* TODO: Combine JUMPABLE and HAS_TEXT to cache OP(rn) */
208
5f80c4cf 209/* for use after a quantifier and before an EXACT-like node -- japhy */
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210/* it would be nice to rework regcomp.sym to generate this stuff. sigh
211 *
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
218*/
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219#define JUMPABLE(rn) ( \
220 OP(rn) == OPEN || \
3e901dc0 221 (OP(rn) == CLOSE && (!cur_eval || cur_eval->u.eval.close_paren != ARG(rn))) || \
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222 OP(rn) == EVAL || \
223 OP(rn) == SUSPEND || OP(rn) == IFMATCH || \
224 OP(rn) == PLUS || OP(rn) == MINMOD || \
225 OP(rn) == KEEPS || \
226 (PL_regkind[OP(rn)] == CURLY && ARG1(rn) > 0) \
e2d8ce26 227)
ee9b8eae 228#define IS_EXACT(rn) (PL_regkind[OP(rn)] == EXACT)
e2d8ce26 229
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230#define HAS_TEXT(rn) ( IS_EXACT(rn) || PL_regkind[OP(rn)] == REF )
231
232#if 0
233/* Currently these are only used when PL_regkind[OP(rn)] == EXACT so
a4525e78 234 we don't need this definition. XXX These are now out-of-sync*/
ee9b8eae 235#define IS_TEXT(rn) ( OP(rn)==EXACT || OP(rn)==REF || OP(rn)==NREF )
098b07d5 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 )
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237#define IS_TEXTFL(rn) ( OP(rn)==EXACTFL || OP(rn)==REFFL || OP(rn)==NREFFL )
238
239#else
240/* ... so we use this as its faster. */
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241#define IS_TEXT(rn) ( OP(rn)==EXACT || OP(rn)==EXACTL )
242#define IS_TEXTFU(rn) ( OP(rn)==EXACTFU || OP(rn)==EXACTFLU8 || OP(rn)==EXACTFU_SS || OP(rn) == EXACTFA || OP(rn) == EXACTFA_NO_TRIE)
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243#define IS_TEXTF(rn) ( OP(rn)==EXACTF )
244#define IS_TEXTFL(rn) ( OP(rn)==EXACTFL )
245
246#endif
e2d8ce26 247
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248/*
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.
251*/
baa60164 252#define FIND_NEXT_IMPT(rn) STMT_START { \
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253 while (JUMPABLE(rn)) { \
254 const OPCODE type = OP(rn); \
255 if (type == SUSPEND || PL_regkind[type] == CURLY) \
e2d8ce26 256 rn = NEXTOPER(NEXTOPER(rn)); \
3dab1dad 257 else if (type == PLUS) \
cca55fe3 258 rn = NEXTOPER(rn); \
3dab1dad 259 else if (type == IFMATCH) \
a84d97b6 260 rn = (rn->flags == 0) ? NEXTOPER(NEXTOPER(rn)) : rn + ARG(rn); \
e2d8ce26 261 else rn += NEXT_OFF(rn); \
3dab1dad 262 } \
5f80c4cf 263} STMT_END
74750237 264
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KW
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 */
273#define TCount 28
c476f425 274
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DM
275#define SLAB_FIRST(s) (&(s)->states[0])
276#define SLAB_LAST(s) (&(s)->states[PERL_REGMATCH_SLAB_SLOTS-1])
277
a75351a1 278static void S_setup_eval_state(pTHX_ regmatch_info *const reginfo);
bf2039a9 279static void S_cleanup_regmatch_info_aux(pTHX_ void *arg);
bf2039a9 280static regmatch_state * S_push_slab(pTHX);
51371543 281
87c0511b 282#define REGCP_PAREN_ELEMS 3
f067efbf 283#define REGCP_OTHER_ELEMS 3
e0fa7e2b 284#define REGCP_FRAME_ELEMS 1
620d5b66
NC
285/* REGCP_FRAME_ELEMS are not part of the REGCP_OTHER_ELEMS and
286 * are needed for the regexp context stack bookkeeping. */
287
76e3520e 288STATIC CHECKPOINT
92da3157 289S_regcppush(pTHX_ const regexp *rex, I32 parenfloor, U32 maxopenparen)
a0d0e21e 290{
a3b680e6 291 const int retval = PL_savestack_ix;
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DM
292 const int paren_elems_to_push =
293 (maxopenparen - parenfloor) * REGCP_PAREN_ELEMS;
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NC
294 const UV total_elems = paren_elems_to_push + REGCP_OTHER_ELEMS;
295 const UV elems_shifted = total_elems << SAVE_TIGHT_SHIFT;
87c0511b 296 I32 p;
40a82448 297 GET_RE_DEBUG_FLAGS_DECL;
a0d0e21e 298
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299 PERL_ARGS_ASSERT_REGCPPUSH;
300
e49a9654 301 if (paren_elems_to_push < 0)
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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);
e49a9654 305
e0fa7e2b
NC
306 if ((elems_shifted >> SAVE_TIGHT_SHIFT) != total_elems)
307 Perl_croak(aTHX_ "panic: paren_elems_to_push offset %"UVuf
5df417d0 308 " out of range (%lu-%ld)",
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DM
309 total_elems,
310 (unsigned long)maxopenparen,
311 (long)parenfloor);
e0fa7e2b 312
620d5b66 313 SSGROW(total_elems + REGCP_FRAME_ELEMS);
7f69552c 314
495f47a5 315 DEBUG_BUFFERS_r(
92da3157 316 if ((int)maxopenparen > (int)parenfloor)
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DM
317 PerlIO_printf(Perl_debug_log,
318 "rex=0x%"UVxf" offs=0x%"UVxf": saving capture indices:\n",
319 PTR2UV(rex),
320 PTR2UV(rex->offs)
321 );
322 );
92da3157 323 for (p = parenfloor+1; p <= (I32)maxopenparen; p++) {
b1ce53c5 324/* REGCP_PARENS_ELEMS are pushed per pairs of parentheses. */
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FC
325 SSPUSHIV(rex->offs[p].end);
326 SSPUSHIV(rex->offs[p].start);
1ca2007e 327 SSPUSHINT(rex->offs[p].start_tmp);
e7707071 328 DEBUG_BUFFERS_r(PerlIO_printf(Perl_debug_log,
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DM
329 " \\%"UVuf": %"IVdf"(%"IVdf")..%"IVdf"\n",
330 (UV)p,
331 (IV)rex->offs[p].start,
332 (IV)rex->offs[p].start_tmp,
333 (IV)rex->offs[p].end
40a82448 334 ));
a0d0e21e 335 }
b1ce53c5 336/* REGCP_OTHER_ELEMS are pushed in any case, parentheses or no. */
92da3157 337 SSPUSHINT(maxopenparen);
b93070ed
DM
338 SSPUSHINT(rex->lastparen);
339 SSPUSHINT(rex->lastcloseparen);
e0fa7e2b 340 SSPUSHUV(SAVEt_REGCONTEXT | elems_shifted); /* Magic cookie. */
41123dfd 341
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LW
342 return retval;
343}
344
c277df42 345/* These are needed since we do not localize EVAL nodes: */
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YO
346#define REGCP_SET(cp) \
347 DEBUG_STATE_r( \
ab3bbdeb 348 PerlIO_printf(Perl_debug_log, \
e4f74956 349 " Setting an EVAL scope, savestack=%"IVdf"\n", \
ab3bbdeb
YO
350 (IV)PL_savestack_ix)); \
351 cp = PL_savestack_ix
c3464db5 352
ab3bbdeb 353#define REGCP_UNWIND(cp) \
e4f74956 354 DEBUG_STATE_r( \
ab3bbdeb 355 if (cp != PL_savestack_ix) \
e4f74956
YO
356 PerlIO_printf(Perl_debug_log, \
357 " Clearing an EVAL scope, savestack=%"IVdf"..%"IVdf"\n", \
ab3bbdeb
YO
358 (IV)(cp), (IV)PL_savestack_ix)); \
359 regcpblow(cp)
c277df42 360
a8d1f4b4
DM
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;
366
367
f067efbf 368STATIC void
92da3157 369S_regcppop(pTHX_ regexp *rex, U32 *maxopenparen_p)
a0d0e21e 370{
e0fa7e2b 371 UV i;
87c0511b 372 U32 paren;
a3621e74
YO
373 GET_RE_DEBUG_FLAGS_DECL;
374
7918f24d
NC
375 PERL_ARGS_ASSERT_REGCPPOP;
376
b1ce53c5 377 /* Pop REGCP_OTHER_ELEMS before the parentheses loop starts. */
c6bf6a65 378 i = SSPOPUV;
e0fa7e2b
NC
379 assert((i & SAVE_MASK) == SAVEt_REGCONTEXT); /* Check that the magic cookie is there. */
380 i >>= SAVE_TIGHT_SHIFT; /* Parentheses elements to pop. */
b93070ed
DM
381 rex->lastcloseparen = SSPOPINT;
382 rex->lastparen = SSPOPINT;
92da3157 383 *maxopenparen_p = SSPOPINT;
b1ce53c5 384
620d5b66 385 i -= REGCP_OTHER_ELEMS;
b1ce53c5 386 /* Now restore the parentheses context. */
495f47a5
DM
387 DEBUG_BUFFERS_r(
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",
391 PTR2UV(rex),
392 PTR2UV(rex->offs)
393 );
394 );
92da3157 395 paren = *maxopenparen_p;
620d5b66 396 for ( ; i > 0; i -= REGCP_PAREN_ELEMS) {
ea3daa5d 397 SSize_t tmps;
1ca2007e 398 rex->offs[paren].start_tmp = SSPOPINT;
99a90e59
FC
399 rex->offs[paren].start = SSPOPIV;
400 tmps = SSPOPIV;
b93070ed
DM
401 if (paren <= rex->lastparen)
402 rex->offs[paren].end = tmps;
495f47a5
DM
403 DEBUG_BUFFERS_r( PerlIO_printf(Perl_debug_log,
404 " \\%"UVuf": %"IVdf"(%"IVdf")..%"IVdf"%s\n",
405 (UV)paren,
406 (IV)rex->offs[paren].start,
407 (IV)rex->offs[paren].start_tmp,
408 (IV)rex->offs[paren].end,
409 (paren > rex->lastparen ? "(skipped)" : ""));
c277df42 410 );
87c0511b 411 paren--;
a0d0e21e 412 }
daf18116 413#if 1
dafc8851
JH
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}
daf18116
JH
419 * (as of patchlevel 7877) will fail. Then again,
420 * this code seems to be necessary or otherwise
225593e1
DM
421 * this erroneously leaves $1 defined: "1" =~ /^(?:(\d)x)?\d$/
422 * --jhi updated by dapm */
b93070ed 423 for (i = rex->lastparen + 1; i <= rex->nparens; i++) {
92da3157 424 if (i > *maxopenparen_p)
b93070ed
DM
425 rex->offs[i].start = -1;
426 rex->offs[i].end = -1;
495f47a5
DM
427 DEBUG_BUFFERS_r( PerlIO_printf(Perl_debug_log,
428 " \\%"UVuf": %s ..-1 undeffing\n",
429 (UV)i,
92da3157 430 (i > *maxopenparen_p) ? "-1" : " "
495f47a5 431 ));
a0d0e21e 432 }
dafc8851 433#endif
a0d0e21e
LW
434}
435
74088413
DM
436/* restore the parens and associated vars at savestack position ix,
437 * but without popping the stack */
438
439STATIC void
92da3157 440S_regcp_restore(pTHX_ regexp *rex, I32 ix, U32 *maxopenparen_p)
74088413
DM
441{
442 I32 tmpix = PL_savestack_ix;
443 PL_savestack_ix = ix;
92da3157 444 regcppop(rex, maxopenparen_p);
74088413
DM
445 PL_savestack_ix = tmpix;
446}
447
02db2b7b 448#define regcpblow(cp) LEAVE_SCOPE(cp) /* Ignores regcppush()ed data. */
a0d0e21e 449
31c7f561
KW
450STATIC bool
451S_isFOO_lc(pTHX_ const U8 classnum, const U8 character)
452{
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'.
456 *
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,
7aee35ff
KW
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. */
31c7f561
KW
465
466 switch ((_char_class_number) classnum) {
15861f94 467 case _CC_ENUM_ALPHANUMERIC: return isALPHANUMERIC_LC(character);
31c7f561 468 case _CC_ENUM_ALPHA: return isALPHA_LC(character);
e8d596e0
KW
469 case _CC_ENUM_ASCII: return isASCII_LC(character);
470 case _CC_ENUM_BLANK: return isBLANK_LC(character);
b0d691b2
KW
471 case _CC_ENUM_CASED: return isLOWER_LC(character)
472 || isUPPER_LC(character);
e8d596e0 473 case _CC_ENUM_CNTRL: return isCNTRL_LC(character);
31c7f561
KW
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);
e8d596e0 478 case _CC_ENUM_PSXSPC: return isPSXSPC_LC(character);
31c7f561 479 case _CC_ENUM_PUNCT: return isPUNCT_LC(character);
e8d596e0 480 case _CC_ENUM_SPACE: return isSPACE_LC(character);
31c7f561
KW
481 case _CC_ENUM_UPPER: return isUPPER_LC(character);
482 case _CC_ENUM_WORDCHAR: return isWORDCHAR_LC(character);
31c7f561 483 case _CC_ENUM_XDIGIT: return isXDIGIT_LC(character);
31c7f561
KW
484 default: /* VERTSPACE should never occur in locales */
485 Perl_croak(aTHX_ "panic: isFOO_lc() has an unexpected character class '%d'", classnum);
486 }
487
e5964223 488 NOT_REACHED; /* NOTREACHED */
31c7f561
KW
489 return FALSE;
490}
491
3018b823
KW
492STATIC bool
493S_isFOO_utf8_lc(pTHX_ const U8 classnum, const U8* character)
494{
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'.
499 *
500 * This just calls isFOO_lc on the code point for the character if it is in
2f306ab9 501 * the range 0-255. Outside that range, all characters use Unicode
3018b823
KW
502 * rules, ignoring any locale. So use the Unicode function if this class
503 * requires a swash, and use the Unicode macro otherwise. */
504
505 PERL_ARGS_ASSERT_ISFOO_UTF8_LC;
506
507 if (UTF8_IS_INVARIANT(*character)) {
508 return isFOO_lc(classnum, *character);
509 }
510 else if (UTF8_IS_DOWNGRADEABLE_START(*character)) {
511 return isFOO_lc(classnum,
94bb8c36 512 TWO_BYTE_UTF8_TO_NATIVE(*character, *(character + 1)));
3018b823
KW
513 }
514
515 if (classnum < _FIRST_NON_SWASH_CC) {
516
517 /* Initialize the swash unless done already */
518 if (! PL_utf8_swash_ptrs[classnum]) {
519 U8 flags = _CORE_SWASH_INIT_ACCEPT_INVLIST;
2a16ac92
KW
520 PL_utf8_swash_ptrs[classnum] =
521 _core_swash_init("utf8",
522 "",
523 &PL_sv_undef, 1, 0,
524 PL_XPosix_ptrs[classnum], &flags);
3018b823
KW
525 }
526
92a2046b
KW
527 return cBOOL(swash_fetch(PL_utf8_swash_ptrs[classnum], (U8 *)
528 character,
529 TRUE /* is UTF */ ));
3018b823
KW
530 }
531
532 switch ((_char_class_number) classnum) {
533 case _CC_ENUM_SPACE:
534 case _CC_ENUM_PSXSPC: return is_XPERLSPACE_high(character);
535
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);
e1ee3960 539 default: break;
3018b823
KW
540 }
541
e1ee3960 542 return FALSE; /* Things like CNTRL are always below 256 */
3018b823
KW
543}
544
a687059c 545/*
e50aee73 546 * pregexec and friends
a687059c
LW
547 */
548
76234dfb 549#ifndef PERL_IN_XSUB_RE
a687059c 550/*
c277df42 551 - pregexec - match a regexp against a string
a687059c 552 */
c277df42 553I32
5aaab254 554Perl_pregexec(pTHX_ REGEXP * const prog, char* stringarg, char *strend,
ea3daa5d 555 char *strbeg, SSize_t minend, SV *screamer, U32 nosave)
8fd1a950
DM
556/* stringarg: the point in the string at which to begin matching */
557/* strend: pointer to null at end of string */
558/* strbeg: real beginning of string */
559/* minend: end of match must be >= minend bytes after stringarg. */
560/* screamer: SV being matched: only used for utf8 flag, pos() etc; string
561 * itself is accessed via the pointers above */
562/* nosave: For optimizations. */
c277df42 563{
7918f24d
NC
564 PERL_ARGS_ASSERT_PREGEXEC;
565
c277df42 566 return
9041c2e3 567 regexec_flags(prog, stringarg, strend, strbeg, minend, screamer, NULL,
c277df42
IZ
568 nosave ? 0 : REXEC_COPY_STR);
569}
76234dfb 570#endif
22e551b9 571
cad2e5aa 572
6eb5f6b9 573
1a4edc3c
DM
574/* re_intuit_start():
575 *
576 * Based on some optimiser hints, try to find the earliest position in the
577 * string where the regex could match.
578 *
579 * rx: the regex to match against
580 * sv: the SV being matched: only used for utf8 flag; the string
581 * itself is accessed via the pointers below. Note that on
582 * something like an overloaded SV, SvPOK(sv) may be false
583 * and the string pointers may point to something unrelated to
584 * the SV itself.
585 * strbeg: real beginning of string
586 * strpos: the point in the string at which to begin matching
587 * strend: pointer to the byte following the last char of the string
588 * flags currently unused; set to 0
589 * data: currently unused; set to NULL
590 *
591 * The basic idea of re_intuit_start() is to use some known information
592 * about the pattern, namely:
593 *
594 * a) the longest known anchored substring (i.e. one that's at a
595 * constant offset from the beginning of the pattern; but not
596 * necessarily at a fixed offset from the beginning of the
597 * string);
598 * b) the longest floating substring (i.e. one that's not at a constant
599 * offset from the beginning of the pattern);
600 * c) Whether the pattern is anchored to the string; either
601 * an absolute anchor: /^../, or anchored to \n: /^.../m,
602 * or anchored to pos(): /\G/;
603 * d) A start class: a real or synthetic character class which
604 * represents which characters are legal at the start of the pattern;
605 *
606 * to either quickly reject the match, or to find the earliest position
607 * within the string at which the pattern might match, thus avoiding
608 * running the full NFA engine at those earlier locations, only to
609 * eventually fail and retry further along.
610 *
611 * Returns NULL if the pattern can't match, or returns the address within
612 * the string which is the earliest place the match could occur.
613 *
614 * The longest of the anchored and floating substrings is called 'check'
615 * and is checked first. The other is called 'other' and is checked
616 * second. The 'other' substring may not be present. For example,
617 *
618 * /(abc|xyz)ABC\d{0,3}DEFG/
619 *
620 * will have
621 *
622 * check substr (float) = "DEFG", offset 6..9 chars
623 * other substr (anchored) = "ABC", offset 3..3 chars
624 * stclass = [ax]
625 *
626 * Be aware that during the course of this function, sometimes 'anchored'
627 * refers to a substring being anchored relative to the start of the
628 * pattern, and sometimes to the pattern itself being anchored relative to
629 * the string. For example:
630 *
631 * /\dabc/: "abc" is anchored to the pattern;
632 * /^\dabc/: "abc" is anchored to the pattern and the string;
633 * /\d+abc/: "abc" is anchored to neither the pattern nor the string;
634 * /^\d+abc/: "abc" is anchored to neither the pattern nor the string,
635 * but the pattern is anchored to the string.
52a21eb3
DM
636 */
637
cad2e5aa 638char *
52a21eb3
DM
639Perl_re_intuit_start(pTHX_
640 REGEXP * const rx,
641 SV *sv,
642 const char * const strbeg,
643 char *strpos,
644 char *strend,
645 const U32 flags,
646 re_scream_pos_data *data)
cad2e5aa 647{
8d919b0a 648 struct regexp *const prog = ReANY(rx);
6b071d16 649 SSize_t start_shift = prog->check_offset_min;
cad2e5aa 650 /* Should be nonnegative! */
ea3daa5d 651 SSize_t end_shift = 0;
0fc004dd
DM
652 /* current lowest pos in string where the regex can start matching */
653 char *rx_origin = strpos;
eb578fdb 654 SV *check;
f2ed9b32 655 const bool utf8_target = (sv && SvUTF8(sv)) ? 1 : 0; /* if no sv we have to assume bytes */
6480a6c4 656 U8 other_ix = 1 - prog->substrs->check_ix;
6ad5ffb3 657 bool ml_anch = 0;
8f4bf5fc 658 char *other_last = strpos;/* latest pos 'other' substr already checked to */
bd61b366 659 char *check_at = NULL; /* check substr found at this pos */
bbe252da 660 const I32 multiline = prog->extflags & RXf_PMf_MULTILINE;
f8fc2ecf 661 RXi_GET_DECL(prog,progi);
02d5137b
DM
662 regmatch_info reginfo_buf; /* create some info to pass to find_byclass */
663 regmatch_info *const reginfo = &reginfo_buf;
a3621e74
YO
664 GET_RE_DEBUG_FLAGS_DECL;
665
7918f24d 666 PERL_ARGS_ASSERT_RE_INTUIT_START;
c33e64f0
FC
667 PERL_UNUSED_ARG(flags);
668 PERL_UNUSED_ARG(data);
7918f24d 669
1dc475d0
DM
670 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
671 "Intuit: trying to determine minimum start position...\n"));
672
fb9bbddb
DM
673 /* for now, assume that all substr offsets are positive. If at some point
674 * in the future someone wants to do clever things with look-behind and
675 * -ve offsets, they'll need to fix up any code in this function
676 * which uses these offsets. See the thread beginning
677 * <20140113145929.GF27210@iabyn.com>
678 */
679 assert(prog->substrs->data[0].min_offset >= 0);
680 assert(prog->substrs->data[0].max_offset >= 0);
681 assert(prog->substrs->data[1].min_offset >= 0);
682 assert(prog->substrs->data[1].max_offset >= 0);
683 assert(prog->substrs->data[2].min_offset >= 0);
684 assert(prog->substrs->data[2].max_offset >= 0);
685
f7022b5a 686 /* for now, assume that if both present, that the floating substring
83f2232d 687 * doesn't start before the anchored substring.
f7022b5a
DM
688 * If you break this assumption (e.g. doing better optimisations
689 * with lookahead/behind), then you'll need to audit the code in this
690 * function carefully first
691 */
692 assert(
693 ! ( (prog->anchored_utf8 || prog->anchored_substr)
694 && (prog->float_utf8 || prog->float_substr))
695 || (prog->float_min_offset >= prog->anchored_offset));
696
1a4edc3c
DM
697 /* byte rather than char calculation for efficiency. It fails
698 * to quickly reject some cases that can't match, but will reject
699 * them later after doing full char arithmetic */
c344f387 700 if (prog->minlen > strend - strpos) {
a3621e74 701 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
1dc475d0 702 " String too short...\n"));
cad2e5aa 703 goto fail;
2c2d71f5 704 }
d8da0584 705
ab4e48c1 706 RX_MATCH_UTF8_set(rx,utf8_target);
6c3fea77 707 reginfo->is_utf8_target = cBOOL(utf8_target);
bf2039a9 708 reginfo->info_aux = NULL;
9d9163fb 709 reginfo->strbeg = strbeg;
220db18a 710 reginfo->strend = strend;
aed7b151 711 reginfo->is_utf8_pat = cBOOL(RX_UTF8(rx));
02d5137b 712 reginfo->intuit = 1;
1cb48e53
DM
713 /* not actually used within intuit, but zero for safety anyway */
714 reginfo->poscache_maxiter = 0;
02d5137b 715
f2ed9b32 716 if (utf8_target) {
33b8afdf
JH
717 if (!prog->check_utf8 && prog->check_substr)
718 to_utf8_substr(prog);
719 check = prog->check_utf8;
720 } else {
7e0d5ad7
KW
721 if (!prog->check_substr && prog->check_utf8) {
722 if (! to_byte_substr(prog)) {
6b54ddc5 723 NON_UTF8_TARGET_BUT_UTF8_REQUIRED(fail);
7e0d5ad7
KW
724 }
725 }
33b8afdf
JH
726 check = prog->check_substr;
727 }
274cd312 728
1dc475d0
DM
729 /* dump the various substring data */
730 DEBUG_OPTIMISE_MORE_r({
731 int i;
732 for (i=0; i<=2; i++) {
733 SV *sv = (utf8_target ? prog->substrs->data[i].utf8_substr
734 : prog->substrs->data[i].substr);
735 if (!sv)
736 continue;
737
738 PerlIO_printf(Perl_debug_log,
739 " substrs[%d]: min=%"IVdf" max=%"IVdf" end shift=%"IVdf
740 " useful=%"IVdf" utf8=%d [%s]\n",
741 i,
742 (IV)prog->substrs->data[i].min_offset,
743 (IV)prog->substrs->data[i].max_offset,
744 (IV)prog->substrs->data[i].end_shift,
745 BmUSEFUL(sv),
746 utf8_target ? 1 : 0,
747 SvPEEK(sv));
748 }
749 });
750
8e1490ee 751 if (prog->intflags & PREGf_ANCH) { /* Match at \G, beg-of-str or after \n */
9fc7410e
DM
752
753 /* ml_anch: check after \n?
754 *
755 * A note about IMPLICIT: on an un-anchored pattern beginning
756 * with /.*.../, these flags will have been added by the
757 * compiler:
758 * /.*abc/, /.*abc/m: PREGf_IMPLICIT | PREGf_ANCH_MBOL
759 * /.*abc/s: PREGf_IMPLICIT | PREGf_ANCH_SBOL
760 */
7d2d37f5
DM
761 ml_anch = (prog->intflags & PREGf_ANCH_MBOL)
762 && !(prog->intflags & PREGf_IMPLICIT);
cad2e5aa 763
343c8a29 764 if (!ml_anch && !(prog->intflags & PREGf_IMPLICIT)) {
c889ccc8
DM
765 /* we are only allowed to match at BOS or \G */
766
57fcbfa7 767 /* trivially reject if there's a BOS anchor and we're not at BOS.
7bb3b9eb
DM
768 *
769 * Note that we don't try to do a similar quick reject for
770 * \G, since generally the caller will have calculated strpos
771 * based on pos() and gofs, so the string is already correctly
772 * anchored by definition; and handling the exceptions would
773 * be too fiddly (e.g. REXEC_IGNOREPOS).
57fcbfa7 774 */
7bb3b9eb 775 if ( strpos != strbeg
d3d47aac 776 && (prog->intflags & PREGf_ANCH_SBOL))
c889ccc8
DM
777 {
778 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
1dc475d0 779 " Not at start...\n"));
c889ccc8
DM
780 goto fail;
781 }
782
a5d12a4b
DM
783 /* in the presence of an anchor, the anchored (relative to the
784 * start of the regex) substr must also be anchored relative
66b7ec5c
DM
785 * to strpos. So quickly reject if substr isn't found there.
786 * This works for \G too, because the caller will already have
787 * subtracted gofs from pos, and gofs is the offset from the
788 * \G to the start of the regex. For example, in /.abc\Gdef/,
789 * where substr="abcdef", pos()=3, gofs=4, offset_min=1:
790 * caller will have set strpos=pos()-4; we look for the substr
791 * at position pos()-4+1, which lines up with the "a" */
a5d12a4b 792
c889ccc8 793 if (prog->check_offset_min == prog->check_offset_max
d0d44648 794 && !(prog->intflags & PREGf_CANY_SEEN))
c889ccc8
DM
795 {
796 /* Substring at constant offset from beg-of-str... */
d307bf57 797 SSize_t slen = SvCUR(check);
343c8a29 798 char *s = HOP3c(strpos, prog->check_offset_min, strend);
1de06328 799
1dc475d0
DM
800 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
801 " Looking for check substr at fixed offset %"IVdf"...\n",
802 (IV)prog->check_offset_min));
803
7742aa66
DM
804 if (SvTAIL(check)) {
805 /* In this case, the regex is anchored at the end too.
806 * Unless it's a multiline match, the lengths must match
807 * exactly, give or take a \n. NB: slen >= 1 since
808 * the last char of check is \n */
809 if (!multiline
810 && ( strend - s > slen
811 || strend - s < slen - 1
812 || (strend - s == slen && strend[-1] != '\n')))
c889ccc8
DM
813 {
814 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
1dc475d0 815 " String too long...\n"));
c889ccc8
DM
816 goto fail_finish;
817 }
818 /* Now should match s[0..slen-2] */
819 slen--;
c889ccc8 820 }
d307bf57
DM
821 if (slen && (*SvPVX_const(check) != *s
822 || (slen > 1 && memNE(SvPVX_const(check), s, slen))))
823 {
824 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
1dc475d0 825 " String not equal...\n"));
d307bf57
DM
826 goto fail_finish;
827 }
c889ccc8
DM
828
829 check_at = s;
830 goto success_at_start;
cad2e5aa 831 }
cad2e5aa 832 }
cad2e5aa 833 }
0fc004dd 834
c0e0ec46 835 end_shift = prog->check_end_shift;
cad2e5aa 836
19188028 837#ifdef DEBUGGING /* 7/99: reports of failure (with the older version) */
0033605d 838 if (end_shift < 0)
1de06328 839 Perl_croak(aTHX_ "panic: end_shift: %"IVdf" pattern:\n%s\n ",
220fc49f 840 (IV)end_shift, RX_PRECOMP(prog));
2c2d71f5
JH
841#endif
842
2c2d71f5 843 restart:
1de06328 844
66b7ec5c
DM
845 /* This is the (re)entry point of the main loop in this function.
846 * The goal of this loop is to:
847 * 1) find the "check" substring in the region rx_origin..strend
848 * (adjusted by start_shift / end_shift). If not found, reject
849 * immediately.
850 * 2) If it exists, look for the "other" substr too if defined; for
851 * example, if the check substr maps to the anchored substr, then
852 * check the floating substr, and vice-versa. If not found, go
853 * back to (1) with rx_origin suitably incremented.
854 * 3) If we find an rx_origin position that doesn't contradict
855 * either of the substrings, then check the possible additional
856 * constraints on rx_origin of /^.../m or a known start class.
857 * If these fail, then depending on which constraints fail, jump
858 * back to here, or to various other re-entry points further along
859 * that skip some of the first steps.
860 * 4) If we pass all those tests, update the BmUSEFUL() count on the
861 * substring. If the start position was determined to be at the
862 * beginning of the string - so, not rejected, but not optimised,
863 * since we have to run regmatch from position 0 - decrement the
864 * BmUSEFUL() count. Otherwise increment it.
865 */
866
1a4edc3c
DM
867
868 /* first, look for the 'check' substring */
869
1de06328 870 {
c33e64f0
FC
871 U8* start_point;
872 U8* end_point;
c889ccc8 873
c889ccc8 874 DEBUG_OPTIMISE_MORE_r({
1dc475d0 875 PerlIO_printf(Perl_debug_log,
ae5d4331 876 " At restart: rx_origin=%"IVdf" Check offset min: %"IVdf
1dc475d0 877 " Start shift: %"IVdf" End shift %"IVdf
4d281893 878 " Real end Shift: %"IVdf"\n",
197641b6 879 (IV)(rx_origin - strpos),
c889ccc8 880 (IV)prog->check_offset_min,
12fbc530
DM
881 (IV)start_shift,
882 (IV)end_shift,
c889ccc8
DM
883 (IV)prog->check_end_shift);
884 });
1de06328 885
0d331aaf 886 if (prog->intflags & PREGf_CANY_SEEN) {
0fc004dd 887 start_point= (U8*)(rx_origin + start_shift);
12fbc530 888 end_point= (U8*)(strend - end_shift);
557f47af
DM
889 if (start_point > end_point)
890 goto fail_finish;
1de06328 891 } else {
557f47af
DM
892 end_point = HOP3(strend, -end_shift, strbeg);
893 start_point = HOPMAYBE3(rx_origin, start_shift, end_point);
894 if (!start_point)
895 goto fail_finish;
1de06328 896 }
c889ccc8 897
557f47af 898
e0362b86 899 /* If the regex is absolutely anchored to either the start of the
d3d47aac 900 * string (SBOL) or to pos() (ANCH_GPOS), then
e0362b86
DM
901 * check_offset_max represents an upper bound on the string where
902 * the substr could start. For the ANCH_GPOS case, we assume that
903 * the caller of intuit will have already set strpos to
904 * pos()-gofs, so in this case strpos + offset_max will still be
905 * an upper bound on the substr.
906 */
c19c836a
DM
907 if (!ml_anch
908 && prog->intflags & PREGf_ANCH
e0362b86 909 && prog->check_offset_max != SSize_t_MAX)
c19c836a 910 {
1a08ba3a 911 SSize_t len = SvCUR(check) - !!SvTAIL(check);
e0362b86
DM
912 const char * const anchor =
913 (prog->intflags & PREGf_ANCH_GPOS ? strpos : strbeg);
914
915 /* do a bytes rather than chars comparison. It's conservative;
916 * so it skips doing the HOP if the result can't possibly end
917 * up earlier than the old value of end_point.
918 */
919 if ((char*)end_point - anchor > prog->check_offset_max) {
920 end_point = HOP3lim((U8*)anchor,
921 prog->check_offset_max,
922 end_point -len)
923 + len;
924 }
d6ef1678
DM
925 }
926
6bda09f9 927 DEBUG_OPTIMISE_MORE_r({
1dc475d0 928 PerlIO_printf(Perl_debug_log, " fbm_instr len=%d str=<%.*s>\n",
1de06328 929 (int)(end_point - start_point),
fc8cd66c 930 (int)(end_point - start_point) > 20 ? 20 : (int)(end_point - start_point),
1de06328
YO
931 start_point);
932 });
933
ae5d4331 934 check_at = fbm_instr( start_point, end_point,
7fba1cd6 935 check, multiline ? FBMrf_MULTILINE : 0);
c889ccc8 936
8fd34720
DM
937 /* Update the count-of-usability, remove useless subpatterns,
938 unshift s. */
939
940 DEBUG_EXECUTE_r({
941 RE_PV_QUOTED_DECL(quoted, utf8_target, PERL_DEBUG_PAD_ZERO(0),
942 SvPVX_const(check), RE_SV_DUMPLEN(check), 30);
943 PerlIO_printf(Perl_debug_log, " %s %s substr %s%s%s",
944 (check_at ? "Found" : "Did not find"),
945 (check == (utf8_target ? prog->anchored_utf8 : prog->anchored_substr)
946 ? "anchored" : "floating"),
947 quoted,
948 RE_SV_TAIL(check),
949 (check_at ? " at offset " : "...\n") );
950 });
2c2d71f5 951
8fd34720
DM
952 if (!check_at)
953 goto fail_finish;
954 /* Finish the diagnostic message */
955 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log, "%ld...\n", (long)(check_at - strpos)) );
2c2d71f5 956
8fd34720
DM
957 /* set rx_origin to the minimum position where the regex could start
958 * matching, given the constraint of the just-matched check substring.
959 * But don't set it lower than previously.
960 */
fdc003fd 961
8fd34720
DM
962 if (check_at - rx_origin > prog->check_offset_max)
963 rx_origin = HOP3c(check_at, -prog->check_offset_max, rx_origin);
964 }
fdc003fd
DM
965
966
1a4edc3c 967 /* now look for the 'other' substring if defined */
2c2d71f5 968
6480a6c4
DM
969 if (utf8_target ? prog->substrs->data[other_ix].utf8_substr
970 : prog->substrs->data[other_ix].substr)
1de06328 971 {
30944b6d 972 /* Take into account the "other" substring. */
6c3343a6
DM
973 char *last, *last1;
974 char *s;
975 SV* must;
976 struct reg_substr_datum *other;
977
978 do_other_substr:
979 other = &prog->substrs->data[other_ix];
980
981 /* if "other" is anchored:
982 * we've previously found a floating substr starting at check_at.
983 * This means that the regex origin must lie somewhere
984 * between min (rx_origin): HOP3(check_at, -check_offset_max)
985 * and max: HOP3(check_at, -check_offset_min)
986 * (except that min will be >= strpos)
987 * So the fixed substr must lie somewhere between
988 * HOP3(min, anchored_offset)
989 * HOP3(max, anchored_offset) + SvCUR(substr)
990 */
991
992 /* if "other" is floating
993 * Calculate last1, the absolute latest point where the
994 * floating substr could start in the string, ignoring any
995 * constraints from the earlier fixed match. It is calculated
996 * as follows:
997 *
998 * strend - prog->minlen (in chars) is the absolute latest
999 * position within the string where the origin of the regex
1000 * could appear. The latest start point for the floating
1001 * substr is float_min_offset(*) on from the start of the
1002 * regex. last1 simply combines thee two offsets.
1003 *
1004 * (*) You might think the latest start point should be
1005 * float_max_offset from the regex origin, and technically
1006 * you'd be correct. However, consider
1007 * /a\d{2,4}bcd\w/
1008 * Here, float min, max are 3,5 and minlen is 7.
1009 * This can match either
1010 * /a\d\dbcd\w/
1011 * /a\d\d\dbcd\w/
1012 * /a\d\d\d\dbcd\w/
1013 * In the first case, the regex matches minlen chars; in the
1014 * second, minlen+1, in the third, minlen+2.
1015 * In the first case, the floating offset is 3 (which equals
1016 * float_min), in the second, 4, and in the third, 5 (which
1017 * equals float_max). In all cases, the floating string bcd
1018 * can never start more than 4 chars from the end of the
1019 * string, which equals minlen - float_min. As the substring
1020 * starts to match more than float_min from the start of the
1021 * regex, it makes the regex match more than minlen chars,
1022 * and the two cancel each other out. So we can always use
1023 * float_min - minlen, rather than float_max - minlen for the
1024 * latest position in the string.
1025 *
1026 * Note that -minlen + float_min_offset is equivalent (AFAIKT)
1027 * to CHR_SVLEN(must) - !!SvTAIL(must) + prog->float_end_shift
1028 */
1029
e7a14a9c 1030 assert(prog->minlen >= other->min_offset);
6c3343a6
DM
1031 last1 = HOP3c(strend,
1032 other->min_offset - prog->minlen, strbeg);
1033
4d006249 1034 if (other_ix) {/* i.e. if (other-is-float) */
6c3343a6
DM
1035 /* last is the latest point where the floating substr could
1036 * start, *given* any constraints from the earlier fixed
1037 * match. This constraint is that the floating string starts
1038 * <= float_max_offset chars from the regex origin (rx_origin).
1039 * If this value is less than last1, use it instead.
eb3831ce 1040 */
6c3343a6
DM
1041 assert(rx_origin <= last1);
1042 last =
1043 /* this condition handles the offset==infinity case, and
1044 * is a short-cut otherwise. Although it's comparing a
1045 * byte offset to a char length, it does so in a safe way,
1046 * since 1 char always occupies 1 or more bytes,
1047 * so if a string range is (last1 - rx_origin) bytes,
1048 * it will be less than or equal to (last1 - rx_origin)
1049 * chars; meaning it errs towards doing the accurate HOP3
1050 * rather than just using last1 as a short-cut */
1051 (last1 - rx_origin) < other->max_offset
1052 ? last1
1053 : (char*)HOP3lim(rx_origin, other->max_offset, last1);
1054 }
1055 else {
1056 assert(strpos + start_shift <= check_at);
1057 last = HOP4c(check_at, other->min_offset - start_shift,
1058 strbeg, strend);
1059 }
ead917d0 1060
6c3343a6
DM
1061 s = HOP3c(rx_origin, other->min_offset, strend);
1062 if (s < other_last) /* These positions already checked */
1063 s = other_last;
1064
1065 must = utf8_target ? other->utf8_substr : other->substr;
1066 assert(SvPOK(must));
1067 s = fbm_instr(
1068 (unsigned char*)s,
1069 (unsigned char*)last + SvCUR(must) - (SvTAIL(must)!=0),
1070 must,
1071 multiline ? FBMrf_MULTILINE : 0
1072 );
1073 DEBUG_EXECUTE_r({
1074 RE_PV_QUOTED_DECL(quoted, utf8_target, PERL_DEBUG_PAD_ZERO(0),
1075 SvPVX_const(must), RE_SV_DUMPLEN(must), 30);
1076 PerlIO_printf(Perl_debug_log, " %s %s substr %s%s",
1077 s ? "Found" : "Contradicts",
1078 other_ix ? "floating" : "anchored",
1079 quoted, RE_SV_TAIL(must));
1080 });
ead917d0 1081
ead917d0 1082
6c3343a6
DM
1083 if (!s) {
1084 /* last1 is latest possible substr location. If we didn't
1085 * find it before there, we never will */
1086 if (last >= last1) {
1087 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
1088 ", giving up...\n"));
1089 goto fail_finish;
ead917d0
DM
1090 }
1091
6c3343a6
DM
1092 /* try to find the check substr again at a later
1093 * position. Maybe next time we'll find the "other" substr
1094 * in range too */
1095 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
1096 ", trying %s at offset %ld...\n",
1097 (other_ix ? "floating" : "anchored"),
197641b6 1098 (long)(HOP3c(check_at, 1, strend) - strpos)));
6c3343a6
DM
1099
1100 other_last = HOP3c(last, 1, strend) /* highest failure */;
1101 rx_origin =
4d006249 1102 other_ix /* i.e. if other-is-float */
6c3343a6
DM
1103 ? HOP3c(rx_origin, 1, strend)
1104 : HOP4c(last, 1 - other->min_offset, strbeg, strend);
1105 goto restart;
1106 }
1107 else {
1108 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log, " at offset %ld...\n",
197641b6 1109 (long)(s - strpos)));
ead917d0 1110
4d006249 1111 if (other_ix) { /* if (other-is-float) */
6c3343a6
DM
1112 /* other_last is set to s, not s+1, since its possible for
1113 * a floating substr to fail first time, then succeed
1114 * second time at the same floating position; e.g.:
1115 * "-AB--AABZ" =~ /\wAB\d*Z/
1116 * The first time round, anchored and float match at
1117 * "-(AB)--AAB(Z)" then fail on the initial \w character
1118 * class. Second time round, they match at "-AB--A(AB)(Z)".
1119 */
1120 other_last = s;
ead917d0
DM
1121 }
1122 else {
6c3343a6
DM
1123 rx_origin = HOP3c(s, -other->min_offset, strbeg);
1124 other_last = HOP3c(s, 1, strend);
ead917d0 1125 }
6c3343a6 1126 }
cad2e5aa 1127 }
acba93e8
DM
1128 else {
1129 DEBUG_OPTIMISE_MORE_r(
1130 PerlIO_printf(Perl_debug_log,
1131 " Check-only match: offset min:%"IVdf" max:%"IVdf
1c1c599d 1132 " check_at:%"IVdf" rx_origin:%"IVdf" rx_origin-check_at:%"IVdf
acba93e8
DM
1133 " strend-strpos:%"IVdf"\n",
1134 (IV)prog->check_offset_min,
1135 (IV)prog->check_offset_max,
1c1c599d 1136 (IV)(check_at-strpos),
acba93e8 1137 (IV)(rx_origin-strpos),
1c1c599d 1138 (IV)(rx_origin-check_at),
acba93e8
DM
1139 (IV)(strend-strpos)
1140 )
1141 );
1142 }
2c2d71f5 1143
acba93e8 1144 postprocess_substr_matches:
0991020e 1145
1a4edc3c 1146 /* handle the extra constraint of /^.../m if present */
e3c6feb0 1147
7d2d37f5 1148 if (ml_anch && rx_origin != strbeg && rx_origin[-1] != '\n') {
4620cb61
DM
1149 char *s;
1150
a62659bd
DM
1151 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
1152 " looking for /^/m anchor"));
d0880ea7
DM
1153
1154 /* we have failed the constraint of a \n before rx_origin.
2e759faa
DM
1155 * Find the next \n, if any, even if it's beyond the current
1156 * anchored and/or floating substrings. Whether we should be
1157 * scanning ahead for the next \n or the next substr is debatable.
1158 * On the one hand you'd expect rare substrings to appear less
1159 * often than \n's. On the other hand, searching for \n means
1160 * we're effectively flipping been check_substr and "\n" on each
1161 * iteration as the current "rarest" string candidate, which
1162 * means for example that we'll quickly reject the whole string if
1163 * hasn't got a \n, rather than trying every substr position
1164 * first
1165 */
d0880ea7 1166
4620cb61
DM
1167 s = HOP3c(strend, - prog->minlen, strpos);
1168 if (s <= rx_origin ||
1169 ! ( rx_origin = (char *)memchr(rx_origin, '\n', s - rx_origin)))
1170 {
d0880ea7
DM
1171 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
1172 " Did not find /%s^%s/m...\n",
1173 PL_colors[0], PL_colors[1]));
a62659bd
DM
1174 goto fail_finish;
1175 }
d0880ea7 1176
4ada1233
DM
1177 /* earliest possible origin is 1 char after the \n.
1178 * (since *rx_origin == '\n', it's safe to ++ here rather than
1179 * HOP(rx_origin, 1)) */
1180 rx_origin++;
d0880ea7 1181
f4f115de 1182 if (prog->substrs->check_ix == 0 /* check is anchored */
4ada1233 1183 || rx_origin >= HOP3c(check_at, - prog->check_offset_min, strpos))
f4f115de 1184 {
d0880ea7
DM
1185 /* Position contradicts check-string; either because
1186 * check was anchored (and thus has no wiggle room),
4ada1233 1187 * or check was float and rx_origin is above the float range */
d0880ea7
DM
1188 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
1189 " Found /%s^%s/m, restarting lookup for check-string at offset %ld...\n",
4ada1233 1190 PL_colors[0], PL_colors[1], (long)(rx_origin - strpos)));
d0880ea7
DM
1191 goto restart;
1192 }
1193
1194 /* if we get here, the check substr must have been float,
2e759faa 1195 * is in range, and we may or may not have had an anchored
d0880ea7
DM
1196 * "other" substr which still contradicts */
1197 assert(prog->substrs->check_ix); /* check is float */
1198
1199 if (utf8_target ? prog->anchored_utf8 : prog->anchored_substr) {
1200 /* whoops, the anchored "other" substr exists, so we still
1201 * contradict. On the other hand, the float "check" substr
1202 * didn't contradict, so just retry the anchored "other"
1203 * substr */
1204 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
1205 " Found /%s^%s/m at offset %ld, rescanning for anchored from offset %ld...\n",
1206 PL_colors[0], PL_colors[1],
1207 (long)(rx_origin - strpos),
1208 (long)(rx_origin - strpos + prog->anchored_offset)));
1209 goto do_other_substr;
1210 }
1211
1212 /* success: we don't contradict the found floating substring
1213 * (and there's no anchored substr). */
d0880ea7
DM
1214 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
1215 " Found /%s^%s/m at offset %ld...\n",
1216 PL_colors[0], PL_colors[1], (long)(rx_origin - strpos)));
e3c6feb0
DM
1217 }
1218 else {
2e759faa 1219 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
fe4f3442 1220 " (multiline anchor test skipped)\n"));
e3c6feb0
DM
1221 }
1222
ffad1e6a 1223 success_at_start:
e3c6feb0 1224
cad2e5aa 1225
dd170ff5
DM
1226 /* if we have a starting character class, then test that extra constraint.
1227 * (trie stclasses are too expensive to use here, we are better off to
1228 * leave it to regmatch itself) */
1229
f8fc2ecf 1230 if (progi->regstclass && PL_regkind[OP(progi->regstclass)]!=TRIE) {
f8fc2ecf 1231 const U8* const str = (U8*)STRING(progi->regstclass);
0991020e 1232
2c75e362 1233 /* XXX this value could be pre-computed */
f8fc2ecf 1234 const int cl_l = (PL_regkind[OP(progi->regstclass)] == EXACT
2c75e362
DM
1235 ? (reginfo->is_utf8_pat
1236 ? utf8_distance(str + STR_LEN(progi->regstclass), str)
1237 : STR_LEN(progi->regstclass))
66e933ab 1238 : 1);
1de06328 1239 char * endpos;
fa3bb21d 1240 char *s;
000dfd2d
DM
1241 /* latest pos that a matching float substr constrains rx start to */
1242 char *rx_max_float = NULL;
1243
c75a3985
DM
1244 /* if the current rx_origin is anchored, either by satisfying an
1245 * anchored substring constraint, or a /^.../m constraint, then we
1246 * can reject the current origin if the start class isn't found
1247 * at the current position. If we have a float-only match, then
1248 * rx_origin is constrained to a range; so look for the start class
1249 * in that range. if neither, then look for the start class in the
1250 * whole rest of the string */
1251
dd170ff5
DM
1252 /* XXX DAPM it's not clear what the minlen test is for, and why
1253 * it's not used in the floating case. Nothing in the test suite
1254 * causes minlen == 0 here. See <20140313134639.GS12844@iabyn.com>.
1255 * Here are some old comments, which may or may not be correct:
1256 *
1257 * minlen == 0 is possible if regstclass is \b or \B,
1258 * and the fixed substr is ''$.
1259 * Since minlen is already taken into account, rx_origin+1 is
1260 * before strend; accidentally, minlen >= 1 guaranties no false
1261 * positives at rx_origin + 1 even for \b or \B. But (minlen? 1 :
1262 * 0) below assumes that regstclass does not come from lookahead...
1263 * If regstclass takes bytelength more than 1: If charlength==1, OK.
1264 * This leaves EXACTF-ish only, which are dealt with in
1265 * find_byclass().
1266 */
1267
7d2d37f5 1268 if (prog->anchored_substr || prog->anchored_utf8 || ml_anch)
fa3bb21d 1269 endpos= HOP3c(rx_origin, (prog->minlen ? cl_l : 0), strend);
000dfd2d
DM
1270 else if (prog->float_substr || prog->float_utf8) {
1271 rx_max_float = HOP3c(check_at, -start_shift, strbeg);
1272 endpos= HOP3c(rx_max_float, cl_l, strend);
1273 }
1de06328
YO
1274 else
1275 endpos= strend;
1276
1dc475d0
DM
1277 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
1278 " looking for class: start_shift: %"IVdf" check_at: %"IVdf
c43b5520 1279 " rx_origin: %"IVdf" endpos: %"IVdf"\n",
1dc475d0 1280 (IV)start_shift, (IV)(check_at - strbeg),
c43b5520 1281 (IV)(rx_origin - strbeg), (IV)(endpos - strbeg)));
d8080198 1282
c43b5520 1283 s = find_byclass(prog, progi->regstclass, rx_origin, endpos,
f9176b44 1284 reginfo);
be778b1a 1285 if (!s) {
6eb5f6b9 1286 if (endpos == strend) {
a3621e74 1287 DEBUG_EXECUTE_r( PerlIO_printf(Perl_debug_log,
1dc475d0 1288 " Could not match STCLASS...\n") );
6eb5f6b9
JH
1289 goto fail;
1290 }
a3621e74 1291 DEBUG_EXECUTE_r( PerlIO_printf(Perl_debug_log,
1dc475d0 1292 " This position contradicts STCLASS...\n") );
e0eb31e7
DM
1293 if ((prog->intflags & PREGf_ANCH) && !ml_anch
1294 && !(prog->intflags & PREGf_IMPLICIT))
653099ff 1295 goto fail;
9fed8d02 1296
6eb5f6b9 1297 /* Contradict one of substrings */
97136c8a
DM
1298 if (prog->anchored_substr || prog->anchored_utf8) {
1299 if (prog->substrs->check_ix == 1) { /* check is float */
1300 /* Have both, check_string is floating */
1301 assert(rx_origin + start_shift <= check_at);
1302 if (rx_origin + start_shift != check_at) {
1303 /* not at latest position float substr could match:
c75a3985
DM
1304 * Recheck anchored substring, but not floating.
1305 * The condition above is in bytes rather than
1306 * chars for efficiency. It's conservative, in
1307 * that it errs on the side of doing 'goto
1308 * do_other_substr', where a more accurate
1309 * char-based calculation will be done */
97136c8a
DM
1310 DEBUG_EXECUTE_r( PerlIO_printf(Perl_debug_log,
1311 " Looking for anchored substr starting at offset %ld...\n",
1312 (long)(other_last - strpos)) );
1313 goto do_other_substr;
3369914b 1314 }
3369914b
DM
1315 }
1316 }
97136c8a 1317 else {
9fed8d02
DM
1318 /* float-only */
1319
7d2d37f5 1320 if (ml_anch) {
c75a3985
DM
1321 /* In the presence of ml_anch, we might be able to
1322 * find another \n without breaking the current float
1323 * constraint. */
1324
1325 /* strictly speaking this should be HOP3c(..., 1, ...),
1326 * but since we goto a block of code that's going to
1327 * search for the next \n if any, its safe here */
9fed8d02 1328 rx_origin++;
9fed8d02
DM
1329 DEBUG_EXECUTE_r( PerlIO_printf(Perl_debug_log,
1330 " Looking for /%s^%s/m starting at offset %ld...\n",
1331 PL_colors[0], PL_colors[1],
1332 (long)(rx_origin - strpos)) );
9fed8d02 1333 goto postprocess_substr_matches;
ab60c45a 1334 }
c75a3985
DM
1335
1336 /* strictly speaking this can never be true; but might
1337 * be if we ever allow intuit without substrings */
1338 if (!(utf8_target ? prog->float_utf8 : prog->float_substr))
9fed8d02 1339 goto fail;
c75a3985 1340
000dfd2d 1341 rx_origin = rx_max_float;
9fed8d02
DM
1342 }
1343
c75a3985
DM
1344 /* at this point, any matching substrings have been
1345 * contradicted. Start again... */
1346
9fed8d02 1347 rx_origin = HOP3c(rx_origin, 1, strend);
557f47af
DM
1348
1349 /* uses bytes rather than char calculations for efficiency.
1350 * It's conservative: it errs on the side of doing 'goto restart',
1351 * where there is code that does a proper char-based test */
9fed8d02 1352 if (rx_origin + start_shift + end_shift > strend) {
40268e5b 1353 DEBUG_EXECUTE_r( PerlIO_printf(Perl_debug_log,
9fed8d02
DM
1354 " Could not match STCLASS...\n") );
1355 goto fail;
1356 }
1357 DEBUG_EXECUTE_r( PerlIO_printf(Perl_debug_log,
1358 " Looking for %s substr starting at offset %ld...\n",
1359 (prog->substrs->check_ix ? "floating" : "anchored"),
1360 (long)(rx_origin + start_shift - strpos)) );
1361 goto restart;
6eb5f6b9 1362 }
9fed8d02 1363
c75a3985
DM
1364 /* Success !!! */
1365
5f9c6575 1366 if (rx_origin != s) {
a3621e74 1367 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
1dc475d0 1368 " By STCLASS: moving %ld --> %ld\n",
5f9c6575 1369 (long)(rx_origin - strpos), (long)(s - strpos))
b7953727
JH
1370 );
1371 }
1372 else {
a3621e74 1373 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
1dc475d0 1374 " Does not contradict STCLASS...\n");
b7953727
JH
1375 );
1376 }
6eb5f6b9 1377 }
ffad1e6a
DM
1378
1379 /* Decide whether using the substrings helped */
1380
1381 if (rx_origin != strpos) {
1382 /* Fixed substring is found far enough so that the match
1383 cannot start at strpos. */
1384
1385 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log, " try at offset...\n"));
1386 ++BmUSEFUL(utf8_target ? prog->check_utf8 : prog->check_substr); /* hooray/5 */
1387 }
1388 else {
70563e16
DM
1389 /* The found rx_origin position does not prohibit matching at
1390 * strpos, so calling intuit didn't gain us anything. Decrement
1391 * the BmUSEFUL() count on the check substring, and if we reach
1392 * zero, free it. */
1393 if (!(prog->intflags & PREGf_NAUGHTY)
ffad1e6a
DM
1394 && (utf8_target ? (
1395 prog->check_utf8 /* Could be deleted already */
1396 && --BmUSEFUL(prog->check_utf8) < 0
1397 && (prog->check_utf8 == prog->float_utf8)
1398 ) : (
1399 prog->check_substr /* Could be deleted already */
1400 && --BmUSEFUL(prog->check_substr) < 0
1401 && (prog->check_substr == prog->float_substr)
1402 )))
1403 {
1404 /* If flags & SOMETHING - do not do it many times on the same match */
1405 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log, " ... Disabling check substring...\n"));
1406 /* XXX Does the destruction order has to change with utf8_target? */
1407 SvREFCNT_dec(utf8_target ? prog->check_utf8 : prog->check_substr);
1408 SvREFCNT_dec(utf8_target ? prog->check_substr : prog->check_utf8);
1409 prog->check_substr = prog->check_utf8 = NULL; /* disable */
1410 prog->float_substr = prog->float_utf8 = NULL; /* clear */
1411 check = NULL; /* abort */
ffad1e6a
DM
1412 /* XXXX This is a remnant of the old implementation. It
1413 looks wasteful, since now INTUIT can use many
1414 other heuristics. */
1415 prog->extflags &= ~RXf_USE_INTUIT;
ffad1e6a
DM
1416 }
1417 }
1418
1419 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
1420 "Intuit: %sSuccessfully guessed:%s match at offset %ld\n",
1421 PL_colors[4], PL_colors[5], (long)(rx_origin - strpos)) );
1422
c765d6e0 1423 return rx_origin;
2c2d71f5
JH
1424
1425 fail_finish: /* Substring not found */
33b8afdf 1426 if (prog->check_substr || prog->check_utf8) /* could be removed already */
f2ed9b32 1427 BmUSEFUL(utf8_target ? prog->check_utf8 : prog->check_substr) += 5; /* hooray */
cad2e5aa 1428 fail:
a3621e74 1429 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log, "%sMatch rejected by optimizer%s\n",
e4584336 1430 PL_colors[4], PL_colors[5]));
bd61b366 1431 return NULL;
cad2e5aa 1432}
9661b544 1433
70563e16 1434
a0a388a1 1435#define DECL_TRIE_TYPE(scan) \
e7fd4aa1 1436 const enum { trie_plain, trie_utf8, trie_utf8_fold, trie_latin_utf8_fold, \
a4525e78
KW
1437 trie_utf8_exactfa_fold, trie_latin_utf8_exactfa_fold, \
1438 trie_utf8l, trie_flu8 } \
e7fd4aa1
KW
1439 trie_type = ((scan->flags == EXACT) \
1440 ? (utf8_target ? trie_utf8 : trie_plain) \
a4525e78
KW
1441 : (scan->flags == EXACTL) \
1442 ? (utf8_target ? trie_utf8l : trie_plain) \
1443 : (scan->flags == EXACTFA) \
1444 ? (utf8_target \
1445 ? trie_utf8_exactfa_fold \
1446 : trie_latin_utf8_exactfa_fold) \
1447 : (scan->flags == EXACTFLU8 \
1448 ? trie_flu8 \
1449 : (utf8_target \
1450 ? trie_utf8_fold \
1451 : trie_latin_utf8_fold)))
fab2782b 1452
fd3249ee 1453#define REXEC_TRIE_READ_CHAR(trie_type, trie, widecharmap, uc, uscan, len, uvc, charid, foldlen, foldbuf, uniflags) \
baa60164 1454STMT_START { \
fab2782b 1455 STRLEN skiplen; \
baa60164 1456 U8 flags = FOLD_FLAGS_FULL; \
fab2782b 1457 switch (trie_type) { \
a4525e78
KW
1458 case trie_flu8: \
1459 goto do_trie_utf8_fold; \
31f05a37 1460 case trie_utf8_exactfa_fold: \
baa60164 1461 flags |= FOLD_FLAGS_NOMIX_ASCII; \
924ba076 1462 /* FALLTHROUGH */ \
fab2782b 1463 case trie_utf8_fold: \
a4525e78 1464 do_trie_utf8_fold: \
fab2782b 1465 if ( foldlen>0 ) { \
c80e42f3 1466 uvc = utf8n_to_uvchr( (const U8*) uscan, UTF8_MAXLEN, &len, uniflags ); \
fab2782b
YO
1467 foldlen -= len; \
1468 uscan += len; \
1469 len=0; \
1470 } else { \
445bf929 1471 uvc = _to_utf8_fold_flags( (const U8*) uc, foldbuf, &foldlen, flags); \
fab2782b
YO
1472 len = UTF8SKIP(uc); \
1473 skiplen = UNISKIP( uvc ); \
1474 foldlen -= skiplen; \
1475 uscan = foldbuf + skiplen; \
1476 } \
1477 break; \
baa60164
KW
1478 case trie_latin_utf8_exactfa_fold: \
1479 flags |= FOLD_FLAGS_NOMIX_ASCII; \
924ba076 1480 /* FALLTHROUGH */ \
fab2782b
YO
1481 case trie_latin_utf8_fold: \
1482 if ( foldlen>0 ) { \
c80e42f3 1483 uvc = utf8n_to_uvchr( (const U8*) uscan, UTF8_MAXLEN, &len, uniflags ); \
fab2782b
YO
1484 foldlen -= len; \
1485 uscan += len; \
1486 len=0; \
1487 } else { \
1488 len = 1; \
31f05a37 1489 uvc = _to_fold_latin1( (U8) *uc, foldbuf, &foldlen, flags); \
fab2782b
YO
1490 skiplen = UNISKIP( uvc ); \
1491 foldlen -= skiplen; \
1492 uscan = foldbuf + skiplen; \
1493 } \
1494 break; \
a4525e78 1495 case trie_utf8l: \
fab2782b 1496 case trie_utf8: \
c80e42f3 1497 uvc = utf8n_to_uvchr( (const U8*) uc, UTF8_MAXLEN, &len, uniflags ); \
fab2782b
YO
1498 break; \
1499 case trie_plain: \
1500 uvc = (UV)*uc; \
1501 len = 1; \
1502 } \
1503 if (uvc < 256) { \
1504 charid = trie->charmap[ uvc ]; \
1505 } \
1506 else { \
1507 charid = 0; \
1508 if (widecharmap) { \
1509 SV** const svpp = hv_fetch(widecharmap, \
1510 (char*)&uvc, sizeof(UV), 0); \
1511 if (svpp) \
1512 charid = (U16)SvIV(*svpp); \
1513 } \
1514 } \
4cadc6a9
YO
1515} STMT_END
1516
ae7c5b9b
KW
1517#define DUMP_EXEC_POS(li,s,doutf8) \
1518 dump_exec_pos(li,s,(reginfo->strend),(reginfo->strbeg), \
1519 startpos, doutf8)
1520
c84a03c5 1521#define REXEC_FBC_EXACTISH_SCAN(COND) \
4cadc6a9
YO
1522STMT_START { \
1523 while (s <= e) { \
c84a03c5 1524 if ( (COND) \
fac1af77 1525 && (ln == 1 || folder(s, pat_string, ln)) \
02d5137b 1526 && (reginfo->intuit || regtry(reginfo, &s)) )\
4cadc6a9
YO
1527 goto got_it; \
1528 s++; \
1529 } \
1530} STMT_END
1531
c84a03c5 1532#define REXEC_FBC_UTF8_SCAN(CODE) \
4cadc6a9 1533STMT_START { \
9a902117 1534 while (s < strend) { \
c84a03c5 1535 CODE \
9a902117 1536 s += UTF8SKIP(s); \
4cadc6a9
YO
1537 } \
1538} STMT_END
1539
c84a03c5 1540#define REXEC_FBC_SCAN(CODE) \
4cadc6a9
YO
1541STMT_START { \
1542 while (s < strend) { \
c84a03c5 1543 CODE \
4cadc6a9
YO
1544 s++; \
1545 } \
1546} STMT_END
1547
05bd126c
KW
1548#define REXEC_FBC_UTF8_CLASS_SCAN(COND) \
1549REXEC_FBC_UTF8_SCAN( /* Loops while (s < strend) */ \
1550 if (COND) { \
1551 if (tmp && (reginfo->intuit || regtry(reginfo, &s))) \
1552 goto got_it; \
1553 else \
1554 tmp = doevery; \
1555 } \
1556 else \
1557 tmp = 1; \
4cadc6a9
YO
1558)
1559
05bd126c
KW
1560#define REXEC_FBC_CLASS_SCAN(COND) \
1561REXEC_FBC_SCAN( /* Loops while (s < strend) */ \
1562 if (COND) { \
1563 if (tmp && (reginfo->intuit || regtry(reginfo, &s))) \
1564 goto got_it; \
1565 else \
1566 tmp = doevery; \
1567 } \
1568 else \
1569 tmp = 1; \
4cadc6a9
YO
1570)
1571
c84a03c5 1572#define REXEC_FBC_CSCAN(CONDUTF8,COND) \
baa60164 1573 if (utf8_target) { \
c84a03c5 1574 REXEC_FBC_UTF8_CLASS_SCAN(CONDUTF8); \
e1d1eefb
YO
1575 } \
1576 else { \
c84a03c5 1577 REXEC_FBC_CLASS_SCAN(COND); \
d981ef24 1578 }
05bd126c 1579
05bd126c
KW
1580/* The three macros below are slightly different versions of the same logic.
1581 *
1582 * The first is for /a and /aa when the target string is UTF-8. This can only
1583 * match ascii, but it must advance based on UTF-8. The other two handle the
1584 * non-UTF-8 and the more generic UTF-8 cases. In all three, we are looking
1585 * for the boundary (or non-boundary) between a word and non-word character.
1586 * The utf8 and non-utf8 cases have the same logic, but the details must be
1587 * different. Find the "wordness" of the character just prior to this one, and
1588 * compare it with the wordness of this one. If they differ, we have a
1589 * boundary. At the beginning of the string, pretend that the previous
1590 * character was a new-line.
1591 *
1592 * All these macros uncleanly have side-effects with each other and outside
1593 * variables. So far it's been too much trouble to clean-up
1594 *
1595 * TEST_NON_UTF8 is the macro or function to call to test if its byte input is
1596 * a word character or not.
1597 * IF_SUCCESS is code to do if it finds that we are at a boundary between
1598 * word/non-word
1599 * IF_FAIL is code to do if we aren't at a boundary between word/non-word
1600 *
1601 * Exactly one of the two IF_FOO parameters is a no-op, depending on whether we
1602 * are looking for a boundary or for a non-boundary. If we are looking for a
1603 * boundary, we want IF_FAIL to be the no-op, and for IF_SUCCESS to go out and
1604 * see if this tentative match actually works, and if so, to quit the loop
1605 * here. And vice-versa if we are looking for a non-boundary.
1606 *
1607 * 'tmp' below in the next three macros in the REXEC_FBC_SCAN and
1608 * REXEC_FBC_UTF8_SCAN loops is a loop invariant, a bool giving the return of
1609 * TEST_NON_UTF8(s-1). To see this, note that that's what it is defined to be
1610 * at entry to the loop, and to get to the IF_FAIL branch, tmp must equal
1611 * TEST_NON_UTF8(s), and in the opposite branch, IF_SUCCESS, tmp is that
1612 * complement. But in that branch we complement tmp, meaning that at the
1613 * bottom of the loop tmp is always going to be equal to TEST_NON_UTF8(s),
1614 * which means at the top of the loop in the next iteration, it is
1615 * TEST_NON_UTF8(s-1) */
b2f4e957 1616#define FBC_UTF8_A(TEST_NON_UTF8, IF_SUCCESS, IF_FAIL) \
05bd126c
KW
1617 tmp = (s != reginfo->strbeg) ? UCHARAT(s - 1) : '\n'; \
1618 tmp = TEST_NON_UTF8(tmp); \
1619 REXEC_FBC_UTF8_SCAN( /* advances s while s < strend */ \
1620 if (tmp == ! TEST_NON_UTF8((U8) *s)) { \
1621 tmp = !tmp; \
1622 IF_SUCCESS; /* Is a boundary if values for s-1 and s differ */ \
1623 } \
1624 else { \
1625 IF_FAIL; \
1626 } \
1627 ); \
1628
1629/* Like FBC_UTF8_A, but TEST_UV is a macro which takes a UV as its input, and
1630 * TEST_UTF8 is a macro that for the same input code points returns identically
1631 * to TEST_UV, but takes a pointer to a UTF-8 encoded string instead */
236d82fd 1632#define FBC_UTF8(TEST_UV, TEST_UTF8, IF_SUCCESS, IF_FAIL) \
05bd126c
KW
1633 if (s == reginfo->strbeg) { \
1634 tmp = '\n'; \
1635 } \
1636 else { /* Back-up to the start of the previous character */ \
1637 U8 * const r = reghop3((U8*)s, -1, (U8*)reginfo->strbeg); \
1638 tmp = utf8n_to_uvchr(r, (U8*) reginfo->strend - r, \
3db24e1e 1639 0, UTF8_ALLOW_DEFAULT); \
05bd126c
KW
1640 } \
1641 tmp = TEST_UV(tmp); \
1642 LOAD_UTF8_CHARCLASS_ALNUM(); \
1643 REXEC_FBC_UTF8_SCAN( /* advances s while s < strend */ \
1644 if (tmp == ! (TEST_UTF8((U8 *) s))) { \
1645 tmp = !tmp; \
1646 IF_SUCCESS; \
1647 } \
1648 else { \
1649 IF_FAIL; \
1650 } \
1651 );
cfaf538b 1652
05bd126c
KW
1653/* Like the above two macros. UTF8_CODE is the complete code for handling
1654 * UTF-8. Common to the BOUND and NBOUND cases, set-up by the FBC_BOUND, etc
1655 * macros below */
baa60164 1656#define FBC_BOUND_COMMON(UTF8_CODE, TEST_NON_UTF8, IF_SUCCESS, IF_FAIL) \
63ac0dad 1657 if (utf8_target) { \
05bd126c 1658 UTF8_CODE \
63ac0dad
KW
1659 } \
1660 else { /* Not utf8 */ \
9d9163fb 1661 tmp = (s != reginfo->strbeg) ? UCHARAT(s - 1) : '\n'; \
63ac0dad 1662 tmp = TEST_NON_UTF8(tmp); \
05bd126c 1663 REXEC_FBC_SCAN( /* advances s while s < strend */ \
63ac0dad 1664 if (tmp == ! TEST_NON_UTF8((U8) *s)) { \
63ac0dad 1665 IF_SUCCESS; \
760cfa8e 1666 tmp = !tmp; \
63ac0dad
KW
1667 } \
1668 else { \
1669 IF_FAIL; \
1670 } \
1671 ); \
1672 } \
c8519dc7
KW
1673 /* Here, things have been set up by the previous code so that tmp is the \
1674 * return of TEST_NON_UTF(s-1) or TEST_UTF8(s-1) (depending on the \
1675 * utf8ness of the target). We also have to check if this matches against \
1676 * the EOS, which we treat as a \n (which is the same value in both UTF-8 \
1677 * or non-UTF8, so can use the non-utf8 test condition even for a UTF-8 \
1678 * string */ \
1679 if (tmp == ! TEST_NON_UTF8('\n')) { \
1680 IF_SUCCESS; \
1681 } \
1682 else { \
1683 IF_FAIL; \
1684 }
63ac0dad 1685
ae7c5b9b
KW
1686/* This is the macro to use when we want to see if something that looks like it
1687 * could match, actually does, and if so exits the loop */
1688#define REXEC_FBC_TRYIT \
1689 if ((reginfo->intuit || regtry(reginfo, &s))) \
1690 goto got_it
1691
1692/* The only difference between the BOUND and NBOUND cases is that
1693 * REXEC_FBC_TRYIT is called when matched in BOUND, and when non-matched in
1694 * NBOUND. This is accomplished by passing it as either the if or else clause,
1695 * with the other one being empty (PLACEHOLDER is defined as empty).
1696 *
1697 * The TEST_FOO parameters are for operating on different forms of input, but
1698 * all should be ones that return identically for the same underlying code
1699 * points */
1700#define FBC_BOUND(TEST_NON_UTF8, TEST_UV, TEST_UTF8) \
1701 FBC_BOUND_COMMON( \
1702 FBC_UTF8(TEST_UV, TEST_UTF8, REXEC_FBC_TRYIT, PLACEHOLDER), \
1703 TEST_NON_UTF8, REXEC_FBC_TRYIT, PLACEHOLDER)
1704
1705#define FBC_BOUND_A(TEST_NON_UTF8, TEST_UV, TEST_UTF8) \
1706 FBC_BOUND_COMMON( \
1707 FBC_UTF8_A(TEST_NON_UTF8, REXEC_FBC_TRYIT, PLACEHOLDER), \
1708 TEST_NON_UTF8, REXEC_FBC_TRYIT, PLACEHOLDER)
1709
1710#define FBC_NBOUND(TEST_NON_UTF8, TEST_UV, TEST_UTF8) \
1711 FBC_BOUND_COMMON( \
1712 FBC_UTF8(TEST_UV, TEST_UTF8, PLACEHOLDER, REXEC_FBC_TRYIT), \
1713 TEST_NON_UTF8, PLACEHOLDER, REXEC_FBC_TRYIT)
1714
1715#define FBC_NBOUND_A(TEST_NON_UTF8, TEST_UV, TEST_UTF8) \
1716 FBC_BOUND_COMMON( \
1717 FBC_UTF8_A(TEST_NON_UTF8, PLACEHOLDER, REXEC_FBC_TRYIT), \
1718 TEST_NON_UTF8, PLACEHOLDER, REXEC_FBC_TRYIT)
1719
05bd126c 1720
786e8c11 1721/* We know what class REx starts with. Try to find this position... */
02d5137b 1722/* if reginfo->intuit, its a dryrun */
786e8c11
YO
1723/* annoyingly all the vars in this routine have different names from their counterparts
1724 in regmatch. /grrr */
3c3eec57 1725STATIC char *
07be1b83 1726S_find_byclass(pTHX_ regexp * prog, const regnode *c, char *s,
f9176b44 1727 const char *strend, regmatch_info *reginfo)
a687059c 1728{
73104a1b
KW
1729 dVAR;
1730 const I32 doevery = (prog->intflags & PREGf_SKIP) == 0;
1731 char *pat_string; /* The pattern's exactish string */
1732 char *pat_end; /* ptr to end char of pat_string */
1733 re_fold_t folder; /* Function for computing non-utf8 folds */
1734 const U8 *fold_array; /* array for folding ords < 256 */
1735 STRLEN ln;
1736 STRLEN lnc;
73104a1b
KW
1737 U8 c1;
1738 U8 c2;
1739 char *e;
1740 I32 tmp = 1; /* Scratch variable? */
ba44c216 1741 const bool utf8_target = reginfo->is_utf8_target;
73104a1b 1742 UV utf8_fold_flags = 0;
f9176b44 1743 const bool is_utf8_pat = reginfo->is_utf8_pat;
3018b823
KW
1744 bool to_complement = FALSE; /* Invert the result? Taking the xor of this
1745 with a result inverts that result, as 0^1 =
1746 1 and 1^1 = 0 */
1747 _char_class_number classnum;
1748
73104a1b 1749 RXi_GET_DECL(prog,progi);
2f7f8cb1 1750
73104a1b 1751 PERL_ARGS_ASSERT_FIND_BYCLASS;
2f7f8cb1 1752
73104a1b
KW
1753 /* We know what class it must start with. */
1754 switch (OP(c)) {
a4525e78 1755 case ANYOFL:
73104a1b
KW
1756 case ANYOF:
1757 if (utf8_target) {
1758 REXEC_FBC_UTF8_CLASS_SCAN(
3db24e1e 1759 reginclass(prog, c, (U8*)s, (U8*) strend, utf8_target));
73104a1b
KW
1760 }
1761 else {
1762 REXEC_FBC_CLASS_SCAN(REGINCLASS(prog, c, (U8*)s));
1763 }
1764 break;
1765 case CANY:
1766 REXEC_FBC_SCAN(
02d5137b 1767 if (tmp && (reginfo->intuit || regtry(reginfo, &s)))
73104a1b
KW
1768 goto got_it;
1769 else
1770 tmp = doevery;
1771 );
1772 break;
1773
098b07d5
KW
1774 case EXACTFA_NO_TRIE: /* This node only generated for non-utf8 patterns */
1775 assert(! is_utf8_pat);
924ba076 1776 /* FALLTHROUGH */
73104a1b 1777 case EXACTFA:
984e6dd1 1778 if (is_utf8_pat || utf8_target) {
73104a1b
KW
1779 utf8_fold_flags = FOLDEQ_UTF8_NOMIX_ASCII;
1780 goto do_exactf_utf8;
1781 }
1782 fold_array = PL_fold_latin1; /* Latin1 folds are not affected by */
1783 folder = foldEQ_latin1; /* /a, except the sharp s one which */
1784 goto do_exactf_non_utf8; /* isn't dealt with by these */
77a6d856 1785
2fdb7295
KW
1786 case EXACTF: /* This node only generated for non-utf8 patterns */
1787 assert(! is_utf8_pat);
73104a1b 1788 if (utf8_target) {
73104a1b
KW
1789 utf8_fold_flags = 0;
1790 goto do_exactf_utf8;
1791 }
1792 fold_array = PL_fold;
1793 folder = foldEQ;
1794 goto do_exactf_non_utf8;
1795
1796 case EXACTFL:
31f05a37 1797 if (is_utf8_pat || utf8_target || IN_UTF8_CTYPE_LOCALE) {
cea315b6 1798 utf8_fold_flags = FOLDEQ_LOCALE;
73104a1b
KW
1799 goto do_exactf_utf8;
1800 }
1801 fold_array = PL_fold_locale;
1802 folder = foldEQ_locale;
1803 goto do_exactf_non_utf8;
3c760661 1804
73104a1b 1805 case EXACTFU_SS:
984e6dd1 1806 if (is_utf8_pat) {
73104a1b
KW
1807 utf8_fold_flags = FOLDEQ_S2_ALREADY_FOLDED;
1808 }
1809 goto do_exactf_utf8;
16d951b7 1810
a4525e78
KW
1811 case EXACTFLU8:
1812 if (! utf8_target) { /* All code points in this node require
1813 UTF-8 to express. */
1814 break;
1815 }
1816 utf8_fold_flags = FOLDEQ_S2_ALREADY_FOLDED;
1817 goto do_exactf_utf8;
1818
73104a1b 1819 case EXACTFU:
984e6dd1
DM
1820 if (is_utf8_pat || utf8_target) {
1821 utf8_fold_flags = is_utf8_pat ? FOLDEQ_S2_ALREADY_FOLDED : 0;
73104a1b
KW
1822 goto do_exactf_utf8;
1823 }
fac1af77 1824
73104a1b
KW
1825 /* Any 'ss' in the pattern should have been replaced by regcomp,
1826 * so we don't have to worry here about this single special case
1827 * in the Latin1 range */
1828 fold_array = PL_fold_latin1;
1829 folder = foldEQ_latin1;
1830
924ba076 1831 /* FALLTHROUGH */
73104a1b
KW
1832
1833 do_exactf_non_utf8: /* Neither pattern nor string are UTF8, and there
1834 are no glitches with fold-length differences
1835 between the target string and pattern */
1836
1837 /* The idea in the non-utf8 EXACTF* cases is to first find the
1838 * first character of the EXACTF* node and then, if necessary,
1839 * case-insensitively compare the full text of the node. c1 is the
1840 * first character. c2 is its fold. This logic will not work for
1841 * Unicode semantics and the german sharp ss, which hence should
1842 * not be compiled into a node that gets here. */
1843 pat_string = STRING(c);
1844 ln = STR_LEN(c); /* length to match in octets/bytes */
1845
1846 /* We know that we have to match at least 'ln' bytes (which is the
1847 * same as characters, since not utf8). If we have to match 3
1848 * characters, and there are only 2 availabe, we know without
1849 * trying that it will fail; so don't start a match past the
1850 * required minimum number from the far end */
ea3daa5d 1851 e = HOP3c(strend, -((SSize_t)ln), s);
73104a1b 1852
02d5137b 1853 if (reginfo->intuit && e < s) {
73104a1b
KW
1854 e = s; /* Due to minlen logic of intuit() */
1855 }
fac1af77 1856
73104a1b
KW
1857 c1 = *pat_string;
1858 c2 = fold_array[c1];
1859 if (c1 == c2) { /* If char and fold are the same */
1860 REXEC_FBC_EXACTISH_SCAN(*(U8*)s == c1);
1861 }
1862 else {
1863 REXEC_FBC_EXACTISH_SCAN(*(U8*)s == c1 || *(U8*)s == c2);
1864 }
1865 break;
fac1af77 1866
73104a1b
KW
1867 do_exactf_utf8:
1868 {
1869 unsigned expansion;
1870
1871 /* If one of the operands is in utf8, we can't use the simpler folding
1872 * above, due to the fact that many different characters can have the
1873 * same fold, or portion of a fold, or different- length fold */
1874 pat_string = STRING(c);
1875 ln = STR_LEN(c); /* length to match in octets/bytes */
1876 pat_end = pat_string + ln;
984e6dd1 1877 lnc = is_utf8_pat /* length to match in characters */
73104a1b
KW
1878 ? utf8_length((U8 *) pat_string, (U8 *) pat_end)
1879 : ln;
1880
1881 /* We have 'lnc' characters to match in the pattern, but because of
1882 * multi-character folding, each character in the target can match
1883 * up to 3 characters (Unicode guarantees it will never exceed
1884 * this) if it is utf8-encoded; and up to 2 if not (based on the
1885 * fact that the Latin 1 folds are already determined, and the
1886 * only multi-char fold in that range is the sharp-s folding to
1887 * 'ss'. Thus, a pattern character can match as little as 1/3 of a
1888 * string character. Adjust lnc accordingly, rounding up, so that
1889 * if we need to match at least 4+1/3 chars, that really is 5. */
1890 expansion = (utf8_target) ? UTF8_MAX_FOLD_CHAR_EXPAND : 2;
1891 lnc = (lnc + expansion - 1) / expansion;
1892
1893 /* As in the non-UTF8 case, if we have to match 3 characters, and
1894 * only 2 are left, it's guaranteed to fail, so don't start a
1895 * match that would require us to go beyond the end of the string
1896 */
ea3daa5d 1897 e = HOP3c(strend, -((SSize_t)lnc), s);
73104a1b 1898
02d5137b 1899 if (reginfo->intuit && e < s) {
73104a1b
KW
1900 e = s; /* Due to minlen logic of intuit() */
1901 }
0658cdde 1902
73104a1b
KW
1903 /* XXX Note that we could recalculate e to stop the loop earlier,
1904 * as the worst case expansion above will rarely be met, and as we
1905 * go along we would usually find that e moves further to the left.
1906 * This would happen only after we reached the point in the loop
1907 * where if there were no expansion we should fail. Unclear if
1908 * worth the expense */
1909
1910 while (s <= e) {
1911 char *my_strend= (char *)strend;
1912 if (foldEQ_utf8_flags(s, &my_strend, 0, utf8_target,
984e6dd1 1913 pat_string, NULL, ln, is_utf8_pat, utf8_fold_flags)
02d5137b 1914 && (reginfo->intuit || regtry(reginfo, &s)) )
73104a1b
KW
1915 {
1916 goto got_it;
1917 }
1918 s += (utf8_target) ? UTF8SKIP(s) : 1;
1919 }
1920 break;
1921 }
236d82fd 1922
73104a1b 1923 case BOUNDL:
236d82fd 1924 FBC_BOUND(isWORDCHAR_LC, isWORDCHAR_LC_uvchr, isWORDCHAR_LC_utf8);
73104a1b
KW
1925 break;
1926 case NBOUNDL:
236d82fd 1927 FBC_NBOUND(isWORDCHAR_LC, isWORDCHAR_LC_uvchr, isWORDCHAR_LC_utf8);
73104a1b
KW
1928 break;
1929 case BOUND:
236d82fd 1930 FBC_BOUND(isWORDCHAR, isWORDCHAR_uni, isWORDCHAR_utf8);
73104a1b
KW
1931 break;
1932 case BOUNDA:
236d82fd 1933 FBC_BOUND_A(isWORDCHAR_A, isWORDCHAR_A, isWORDCHAR_A);
73104a1b
KW
1934 break;
1935 case NBOUND:
236d82fd 1936 FBC_NBOUND(isWORDCHAR, isWORDCHAR_uni, isWORDCHAR_utf8);
73104a1b
KW
1937 break;
1938 case NBOUNDA:
236d82fd 1939 FBC_NBOUND_A(isWORDCHAR_A, isWORDCHAR_A, isWORDCHAR_A);
73104a1b
KW
1940 break;
1941 case BOUNDU:
236d82fd 1942 FBC_BOUND(isWORDCHAR_L1, isWORDCHAR_uni, isWORDCHAR_utf8);
73104a1b
KW
1943 break;
1944 case NBOUNDU:
236d82fd 1945 FBC_NBOUND(isWORDCHAR_L1, isWORDCHAR_uni, isWORDCHAR_utf8);
73104a1b 1946 break;
73104a1b
KW
1947 case LNBREAK:
1948 REXEC_FBC_CSCAN(is_LNBREAK_utf8_safe(s, strend),
1949 is_LNBREAK_latin1_safe(s, strend)
1950 );
1951 break;
3018b823
KW
1952
1953 /* The argument to all the POSIX node types is the class number to pass to
1954 * _generic_isCC() to build a mask for searching in PL_charclass[] */
1955
1956 case NPOSIXL:
1957 to_complement = 1;
1958 /* FALLTHROUGH */
1959
1960 case POSIXL:
3018b823
KW
1961 REXEC_FBC_CSCAN(to_complement ^ cBOOL(isFOO_utf8_lc(FLAGS(c), (U8 *) s)),
1962 to_complement ^ cBOOL(isFOO_lc(FLAGS(c), *s)));
73104a1b 1963 break;
3018b823
KW
1964
1965 case NPOSIXD:
1966 to_complement = 1;
1967 /* FALLTHROUGH */
1968
1969 case POSIXD:
1970 if (utf8_target) {
1971 goto posix_utf8;
1972 }
1973 goto posixa;
1974
1975 case NPOSIXA:
1976 if (utf8_target) {
1977 /* The complement of something that matches only ASCII matches all
837226c8
KW
1978 * non-ASCII, plus everything in ASCII that isn't in the class. */
1979 REXEC_FBC_UTF8_CLASS_SCAN(! isASCII_utf8(s)
3018b823
KW
1980 || ! _generic_isCC_A(*s, FLAGS(c)));
1981 break;
1982 }
1983
1984 to_complement = 1;
1985 /* FALLTHROUGH */
1986
73104a1b 1987 case POSIXA:
3018b823 1988 posixa:
73104a1b 1989 /* Don't need to worry about utf8, as it can match only a single
3018b823
KW
1990 * byte invariant character. */
1991 REXEC_FBC_CLASS_SCAN(
1992 to_complement ^ cBOOL(_generic_isCC_A(*s, FLAGS(c))));
73104a1b 1993 break;
3018b823
KW
1994
1995 case NPOSIXU:
1996 to_complement = 1;
1997 /* FALLTHROUGH */
1998
1999 case POSIXU:
2000 if (! utf8_target) {
2001 REXEC_FBC_CLASS_SCAN(to_complement ^ cBOOL(_generic_isCC(*s,
2002 FLAGS(c))));
2003 }
2004 else {
2005
2006 posix_utf8:
2007 classnum = (_char_class_number) FLAGS(c);
2008 if (classnum < _FIRST_NON_SWASH_CC) {
2009 while (s < strend) {
2010
2011 /* We avoid loading in the swash as long as possible, but
2012 * should we have to, we jump to a separate loop. This
2013 * extra 'if' statement is what keeps this code from being
2014 * just a call to REXEC_FBC_UTF8_CLASS_SCAN() */
2015 if (UTF8_IS_ABOVE_LATIN1(*s)) {
2016 goto found_above_latin1;
2017 }
2018 if ((UTF8_IS_INVARIANT(*s)
2019 && to_complement ^ cBOOL(_generic_isCC((U8) *s,
2020 classnum)))
2021 || (UTF8_IS_DOWNGRADEABLE_START(*s)
2022 && to_complement ^ cBOOL(
94bb8c36
KW
2023 _generic_isCC(TWO_BYTE_UTF8_TO_NATIVE(*s,
2024 *(s + 1)),
3018b823
KW
2025 classnum))))
2026 {
02d5137b 2027 if (tmp && (reginfo->intuit || regtry(reginfo, &s)))
3018b823
KW
2028 goto got_it;
2029 else {
2030 tmp = doevery;
2031 }
2032 }
2033 else {
2034 tmp = 1;
2035 }
2036 s += UTF8SKIP(s);
2037 }
2038 }
2039 else switch (classnum) { /* These classes are implemented as
2040 macros */
2041 case _CC_ENUM_SPACE: /* XXX would require separate code if we
2042 revert the change of \v matching this */
924ba076 2043 /* FALLTHROUGH */
3018b823
KW
2044
2045 case _CC_ENUM_PSXSPC:
2046 REXEC_FBC_UTF8_CLASS_SCAN(
2047 to_complement ^ cBOOL(isSPACE_utf8(s)));
2048 break;
2049
2050 case _CC_ENUM_BLANK:
2051 REXEC_FBC_UTF8_CLASS_SCAN(
2052 to_complement ^ cBOOL(isBLANK_utf8(s)));
2053 break;
2054
2055 case _CC_ENUM_XDIGIT:
2056 REXEC_FBC_UTF8_CLASS_SCAN(
2057 to_complement ^ cBOOL(isXDIGIT_utf8(s)));
2058 break;
2059
2060 case _CC_ENUM_VERTSPACE:
2061 REXEC_FBC_UTF8_CLASS_SCAN(
2062 to_complement ^ cBOOL(isVERTWS_utf8(s)));
2063 break;
2064
2065 case _CC_ENUM_CNTRL:
2066 REXEC_FBC_UTF8_CLASS_SCAN(
2067 to_complement ^ cBOOL(isCNTRL_utf8(s)));
2068 break;
2069
2070 default:
2071 Perl_croak(aTHX_ "panic: find_byclass() node %d='%s' has an unexpected character class '%d'", OP(c), PL_reg_name[OP(c)], classnum);
e5964223 2072 NOT_REACHED; /* NOTREACHED */
3018b823
KW
2073 }
2074 }
2075 break;
2076
2077 found_above_latin1: /* Here we have to load a swash to get the result
2078 for the current code point */
2079 if (! PL_utf8_swash_ptrs[classnum]) {
2080 U8 flags = _CORE_SWASH_INIT_ACCEPT_INVLIST;
2081 PL_utf8_swash_ptrs[classnum] =
2a16ac92
KW
2082 _core_swash_init("utf8",
2083 "",
2084 &PL_sv_undef, 1, 0,
2085 PL_XPosix_ptrs[classnum], &flags);
3018b823
KW
2086 }
2087
2088 /* This is a copy of the loop above for swash classes, though using the
2089 * FBC macro instead of being expanded out. Since we've loaded the
2090 * swash, we don't have to check for that each time through the loop */
2091 REXEC_FBC_UTF8_CLASS_SCAN(
2092 to_complement ^ cBOOL(_generic_utf8(
2093 classnum,
2094 s,
2095 swash_fetch(PL_utf8_swash_ptrs[classnum],
2096 (U8 *) s, TRUE))));
73104a1b
KW
2097 break;
2098
2099 case AHOCORASICKC:
2100 case AHOCORASICK:
2101 {
2102 DECL_TRIE_TYPE(c);
2103 /* what trie are we using right now */
2104 reg_ac_data *aho = (reg_ac_data*)progi->data->data[ ARG( c ) ];
2105 reg_trie_data *trie = (reg_trie_data*)progi->data->data[ aho->trie ];
2106 HV *widecharmap = MUTABLE_HV(progi->data->data[ aho->trie + 1 ]);
2107
2108 const char *last_start = strend - trie->minlen;
6148ee25 2109#ifdef DEBUGGING
73104a1b 2110 const char *real_start = s;
6148ee25 2111#endif
73104a1b
KW
2112 STRLEN maxlen = trie->maxlen;
2113 SV *sv_points;
2114 U8 **points; /* map of where we were in the input string
2115 when reading a given char. For ASCII this
2116 is unnecessary overhead as the relationship
2117 is always 1:1, but for Unicode, especially
2118 case folded Unicode this is not true. */
2119 U8 foldbuf[ UTF8_MAXBYTES_CASE + 1 ];
2120 U8 *bitmap=NULL;
2121
2122
2123 GET_RE_DEBUG_FLAGS_DECL;
2124
2125 /* We can't just allocate points here. We need to wrap it in
2126 * an SV so it gets freed properly if there is a croak while
2127 * running the match */
2128 ENTER;
2129 SAVETMPS;
2130 sv_points=newSV(maxlen * sizeof(U8 *));
2131 SvCUR_set(sv_points,
2132 maxlen * sizeof(U8 *));
2133 SvPOK_on(sv_points);
2134 sv_2mortal(sv_points);
2135 points=(U8**)SvPV_nolen(sv_points );
2136 if ( trie_type != trie_utf8_fold
2137 && (trie->bitmap || OP(c)==AHOCORASICKC) )
2138 {
2139 if (trie->bitmap)
2140 bitmap=(U8*)trie->bitmap;
2141 else
2142 bitmap=(U8*)ANYOF_BITMAP(c);
2143 }
2144 /* this is the Aho-Corasick algorithm modified a touch
2145 to include special handling for long "unknown char" sequences.
2146 The basic idea being that we use AC as long as we are dealing
2147 with a possible matching char, when we encounter an unknown char
2148 (and we have not encountered an accepting state) we scan forward
2149 until we find a legal starting char.
2150 AC matching is basically that of trie matching, except that when
2151 we encounter a failing transition, we fall back to the current
2152 states "fail state", and try the current char again, a process
2153 we repeat until we reach the root state, state 1, or a legal
2154 transition. If we fail on the root state then we can either
2155 terminate if we have reached an accepting state previously, or
2156 restart the entire process from the beginning if we have not.
2157
2158 */
2159 while (s <= last_start) {
2160 const U32 uniflags = UTF8_ALLOW_DEFAULT;
2161 U8 *uc = (U8*)s;
2162 U16 charid = 0;
2163 U32 base = 1;
2164 U32 state = 1;
2165 UV uvc = 0;
2166 STRLEN len = 0;
2167 STRLEN foldlen = 0;
2168 U8 *uscan = (U8*)NULL;
2169 U8 *leftmost = NULL;
2170#ifdef DEBUGGING
2171 U32 accepted_word= 0;
786e8c11 2172#endif
73104a1b
KW
2173 U32 pointpos = 0;
2174
2175 while ( state && uc <= (U8*)strend ) {
2176 int failed=0;
2177 U32 word = aho->states[ state ].wordnum;
2178
2179 if( state==1 ) {
2180 if ( bitmap ) {
2181 DEBUG_TRIE_EXECUTE_r(
2182 if ( uc <= (U8*)last_start && !BITMAP_TEST(bitmap,*uc) ) {
2183 dump_exec_pos( (char *)uc, c, strend, real_start,
2184 (char *)uc, utf8_target );
2185 PerlIO_printf( Perl_debug_log,
2186 " Scanning for legal start char...\n");
2187 }
2188 );
2189 if (utf8_target) {
2190 while ( uc <= (U8*)last_start && !BITMAP_TEST(bitmap,*uc) ) {
2191 uc += UTF8SKIP(uc);
2192 }
2193 } else {
2194 while ( uc <= (U8*)last_start && !BITMAP_TEST(bitmap,*uc) ) {
2195 uc++;
2196 }
786e8c11 2197 }
73104a1b 2198 s= (char *)uc;
07be1b83 2199 }
73104a1b
KW
2200 if (uc >(U8*)last_start) break;
2201 }
2202
2203 if ( word ) {
2204 U8 *lpos= points[ (pointpos - trie->wordinfo[word].len) % maxlen ];
2205 if (!leftmost || lpos < leftmost) {
2206 DEBUG_r(accepted_word=word);
2207 leftmost= lpos;
7016d6eb 2208 }
73104a1b 2209 if (base==0) break;
7016d6eb 2210
73104a1b
KW
2211 }
2212 points[pointpos++ % maxlen]= uc;
2213 if (foldlen || uc < (U8*)strend) {
2214 REXEC_TRIE_READ_CHAR(trie_type, trie,
2215 widecharmap, uc,
2216 uscan, len, uvc, charid, foldlen,
2217 foldbuf, uniflags);
2218 DEBUG_TRIE_EXECUTE_r({
2219 dump_exec_pos( (char *)uc, c, strend,
2220 real_start, s, utf8_target);
2221 PerlIO_printf(Perl_debug_log,
2222 " Charid:%3u CP:%4"UVxf" ",
2223 charid, uvc);
2224 });
2225 }
2226 else {
2227 len = 0;
2228 charid = 0;
2229 }
07be1b83 2230
73104a1b
KW
2231
2232 do {
6148ee25 2233#ifdef DEBUGGING
73104a1b 2234 word = aho->states[ state ].wordnum;
6148ee25 2235#endif
73104a1b
KW
2236 base = aho->states[ state ].trans.base;
2237
2238 DEBUG_TRIE_EXECUTE_r({
2239 if (failed)
2240 dump_exec_pos( (char *)uc, c, strend, real_start,
2241 s, utf8_target );
2242 PerlIO_printf( Perl_debug_log,
2243 "%sState: %4"UVxf", word=%"UVxf,
2244 failed ? " Fail transition to " : "",
2245 (UV)state, (UV)word);
2246 });
2247 if ( base ) {
2248 U32 tmp;
2249 I32 offset;
2250 if (charid &&
2251 ( ((offset = base + charid
2252 - 1 - trie->uniquecharcount)) >= 0)
2253 && ((U32)offset < trie->lasttrans)
2254 && trie->trans[offset].check == state
2255 && (tmp=trie->trans[offset].next))
2256 {
2257 DEBUG_TRIE_EXECUTE_r(
2258 PerlIO_printf( Perl_debug_log," - legal\n"));
2259 state = tmp;
2260 break;
07be1b83
YO
2261 }
2262 else {
786e8c11 2263 DEBUG_TRIE_EXECUTE_r(
73104a1b 2264 PerlIO_printf( Perl_debug_log," - fail\n"));
786e8c11 2265 failed = 1;
73104a1b 2266 state = aho->fail[state];
07be1b83 2267 }
07be1b83 2268 }
73104a1b
KW
2269 else {
2270 /* we must be accepting here */
2271 DEBUG_TRIE_EXECUTE_r(
2272 PerlIO_printf( Perl_debug_log," - accepting\n"));
2273 failed = 1;
2274 break;
786e8c11 2275 }
73104a1b
KW
2276 } while(state);
2277 uc += len;
2278 if (failed) {
2279 if (leftmost)
2280 break;
2281 if (!state) state = 1;
07be1b83 2282 }
73104a1b
KW
2283 }
2284 if ( aho->states[ state ].wordnum ) {
2285 U8 *lpos = points[ (pointpos - trie->wordinfo[aho->states[ state ].wordnum].len) % maxlen ];
2286 if (!leftmost || lpos < leftmost) {
2287 DEBUG_r(accepted_word=aho->states[ state ].wordnum);
2288 leftmost = lpos;
07be1b83
YO
2289 }
2290 }
73104a1b
KW
2291 if (leftmost) {
2292 s = (char*)leftmost;
2293 DEBUG_TRIE_EXECUTE_r({
2294 PerlIO_printf(
2295 Perl_debug_log,"Matches word #%"UVxf" at position %"IVdf". Trying full pattern...\n",
2296 (UV)accepted_word, (IV)(s - real_start)
2297 );
2298 });
02d5137b 2299 if (reginfo->intuit || regtry(reginfo, &s)) {
73104a1b
KW
2300 FREETMPS;
2301 LEAVE;
2302 goto got_it;
2303 }
2304 s = HOPc(s,1);
2305 DEBUG_TRIE_EXECUTE_r({
2306 PerlIO_printf( Perl_debug_log,"Pattern failed. Looking for new start point...\n");
2307 });
2308 } else {
2309 DEBUG_TRIE_EXECUTE_r(
2310 PerlIO_printf( Perl_debug_log,"No match.\n"));
2311 break;
2312 }
2313 }
2314 FREETMPS;
2315 LEAVE;
2316 }
2317 break;
2318 default:
2319 Perl_croak(aTHX_ "panic: unknown regstclass %d", (int)OP(c));
73104a1b
KW
2320 }
2321 return 0;
2322 got_it:
2323 return s;
6eb5f6b9
JH
2324}
2325
60165aa4
DM
2326/* set RX_SAVED_COPY, RX_SUBBEG etc.
2327 * flags have same meanings as with regexec_flags() */
2328
749f4950
DM
2329static void
2330S_reg_set_capture_string(pTHX_ REGEXP * const rx,
60165aa4
DM
2331 char *strbeg,
2332 char *strend,
2333 SV *sv,
2334 U32 flags,
2335 bool utf8_target)
2336{
2337 struct regexp *const prog = ReANY(rx);
2338
60165aa4
DM
2339 if (flags & REXEC_COPY_STR) {
2340#ifdef PERL_ANY_COW
2341 if (SvCANCOW(sv)) {
2342 if (DEBUG_C_TEST) {
2343 PerlIO_printf(Perl_debug_log,
2344 "Copy on write: regexp capture, type %d\n",
2345 (int) SvTYPE(sv));
2346 }
5411a0e5
DM
2347 /* Create a new COW SV to share the match string and store
2348 * in saved_copy, unless the current COW SV in saved_copy
2349 * is valid and suitable for our purpose */
2350 if (( prog->saved_copy
2351 && SvIsCOW(prog->saved_copy)
2352 && SvPOKp(prog->saved_copy)
2353 && SvIsCOW(sv)
2354 && SvPOKp(sv)
2355 && SvPVX(sv) == SvPVX(prog->saved_copy)))
a76b0e90 2356 {
5411a0e5
DM
2357 /* just reuse saved_copy SV */
2358 if (RXp_MATCH_COPIED(prog)) {
2359 Safefree(prog->subbeg);
2360 RXp_MATCH_COPIED_off(prog);
2361 }
2362 }
2363 else {
2364 /* create new COW SV to share string */
a76b0e90
DM
2365 RX_MATCH_COPY_FREE(rx);
2366 prog->saved_copy = sv_setsv_cow(prog->saved_copy, sv);
a76b0e90 2367 }
5411a0e5
DM
2368 prog->subbeg = (char *)SvPVX_const(prog->saved_copy);
2369 assert (SvPOKp(prog->saved_copy));
60165aa4
DM
2370 prog->sublen = strend - strbeg;
2371 prog->suboffset = 0;
2372 prog->subcoffset = 0;
2373 } else
2374#endif
2375 {
99a90e59
FC
2376 SSize_t min = 0;
2377 SSize_t max = strend - strbeg;
ea3daa5d 2378 SSize_t sublen;
60165aa4
DM
2379
2380 if ( (flags & REXEC_COPY_SKIP_POST)
e322109a 2381 && !(prog->extflags & RXf_PMf_KEEPCOPY) /* //p */
60165aa4
DM
2382 && !(PL_sawampersand & SAWAMPERSAND_RIGHT)
2383 ) { /* don't copy $' part of string */
2384 U32 n = 0;
2385 max = -1;
2386 /* calculate the right-most part of the string covered
2387 * by a capture. Due to look-ahead, this may be to
2388 * the right of $&, so we have to scan all captures */
2389 while (n <= prog->lastparen) {
2390 if (prog->offs[n].end > max)
2391 max = prog->offs[n].end;
2392 n++;
2393 }
2394 if (max == -1)
2395 max = (PL_sawampersand & SAWAMPERSAND_LEFT)
2396 ? prog->offs[0].start
2397 : 0;
2398 assert(max >= 0 && max <= strend - strbeg);
2399 }
2400
2401 if ( (flags & REXEC_COPY_SKIP_PRE)
e322109a 2402 && !(prog->extflags & RXf_PMf_KEEPCOPY) /* //p */
60165aa4
DM
2403 && !(PL_sawampersand & SAWAMPERSAND_LEFT)
2404 ) { /* don't copy $` part of string */
2405 U32 n = 0;
2406 min = max;
2407 /* calculate the left-most part of the string covered
2408 * by a capture. Due to look-behind, this may be to
2409 * the left of $&, so we have to scan all captures */
2410 while (min && n <= prog->lastparen) {
2411 if ( prog->offs[n].start != -1
2412 && prog->offs[n].start < min)
2413 {
2414 min = prog->offs[n].start;
2415 }
2416 n++;
2417 }
2418 if ((PL_sawampersand & SAWAMPERSAND_RIGHT)
2419 && min > prog->offs[0].end
2420 )
2421 min = prog->offs[0].end;
2422
2423 }
2424
2425 assert(min >= 0 && min <= max && min <= strend - strbeg);
2426 sublen = max - min;
2427
2428 if (RX_MATCH_COPIED(rx)) {
2429 if (sublen > prog->sublen)
2430 prog->subbeg =
2431 (char*)saferealloc(prog->subbeg, sublen+1);
2432 }
2433 else
2434 prog->subbeg = (char*)safemalloc(sublen+1);
2435 Copy(strbeg + min, prog->subbeg, sublen, char);
2436 prog->subbeg[sublen] = '\0';
2437 prog->suboffset = min;
2438 prog->sublen = sublen;
2439 RX_MATCH_COPIED_on(rx);
2440 }
2441 prog->subcoffset = prog->suboffset;
2442 if (prog->suboffset && utf8_target) {
2443 /* Convert byte offset to chars.
2444 * XXX ideally should only compute this if @-/@+
2445 * has been seen, a la PL_sawampersand ??? */
2446
2447 /* If there's a direct correspondence between the
2448 * string which we're matching and the original SV,
2449 * then we can use the utf8 len cache associated with
2450 * the SV. In particular, it means that under //g,
2451 * sv_pos_b2u() will use the previously cached
2452 * position to speed up working out the new length of
2453 * subcoffset, rather than counting from the start of
2454 * the string each time. This stops
2455 * $x = "\x{100}" x 1E6; 1 while $x =~ /(.)/g;
2456 * from going quadratic */
2457 if (SvPOKp(sv) && SvPVX(sv) == strbeg)
ea3daa5d
FC
2458 prog->subcoffset = sv_pos_b2u_flags(sv, prog->subcoffset,
2459 SV_GMAGIC|SV_CONST_RETURN);
60165aa4
DM
2460 else
2461 prog->subcoffset = utf8_length((U8*)strbeg,
2462 (U8*)(strbeg+prog->suboffset));
2463 }
2464 }
2465 else {
2466 RX_MATCH_COPY_FREE(rx);
2467 prog->subbeg = strbeg;
2468 prog->suboffset = 0;
2469 prog->subcoffset = 0;
2470 prog->sublen = strend - strbeg;
2471 }
2472}
2473
2474
2475
fae667d5 2476
6eb5f6b9
JH
2477/*
2478 - regexec_flags - match a regexp against a string
2479 */
2480I32
5aaab254 2481Perl_regexec_flags(pTHX_ REGEXP * const rx, char *stringarg, char *strend,
ea3daa5d 2482 char *strbeg, SSize_t minend, SV *sv, void *data, U32 flags)
8fd1a950
DM
2483/* stringarg: the point in the string at which to begin matching */
2484/* strend: pointer to null at end of string */
2485/* strbeg: real beginning of string */
2486/* minend: end of match must be >= minend bytes after stringarg. */
2487/* sv: SV being matched: only used for utf8 flag, pos() etc; string
2488 * itself is accessed via the pointers above */
2489/* data: May be used for some additional optimizations.
d058ec57 2490 Currently unused. */
a340edde 2491/* flags: For optimizations. See REXEC_* in regexp.h */
8fd1a950 2492
6eb5f6b9 2493{
8d919b0a 2494 struct regexp *const prog = ReANY(rx);
5aaab254 2495 char *s;
eb578fdb 2496 regnode *c;
03c83e26 2497 char *startpos;
ea3daa5d
FC
2498 SSize_t minlen; /* must match at least this many chars */
2499 SSize_t dontbother = 0; /* how many characters not to try at end */
f2ed9b32 2500 const bool utf8_target = cBOOL(DO_UTF8(sv));
2757e526 2501 I32 multiline;
f8fc2ecf 2502 RXi_GET_DECL(prog,progi);
02d5137b
DM
2503 regmatch_info reginfo_buf; /* create some info to pass to regtry etc */
2504 regmatch_info *const reginfo = &reginfo_buf;
e9105d30 2505 regexp_paren_pair *swap = NULL;
006f26b2 2506 I32 oldsave;
a3621e74
YO
2507 GET_RE_DEBUG_FLAGS_DECL;
2508
7918f24d 2509 PERL_ARGS_ASSERT_REGEXEC_FLAGS;
9d4ba2ae 2510 PERL_UNUSED_ARG(data);
6eb5f6b9
JH
2511
2512 /* Be paranoid... */
03c83e26 2513 if (prog == NULL || stringarg == NULL) {
6eb5f6b9 2514 Perl_croak(aTHX_ "NULL regexp parameter");
6eb5f6b9
JH
2515 }
2516
6c3fea77 2517 DEBUG_EXECUTE_r(
03c83e26 2518 debug_start_match(rx, utf8_target, stringarg, strend,
6c3fea77
DM
2519 "Matching");
2520 );
8adc0f72 2521
b342a604
DM
2522 startpos = stringarg;
2523
58430ea8 2524 if (prog->intflags & PREGf_GPOS_SEEN) {
d307c076
DM
2525 MAGIC *mg;
2526
fef7148b
DM
2527 /* set reginfo->ganch, the position where \G can match */
2528
2529 reginfo->ganch =
2530 (flags & REXEC_IGNOREPOS)
2531 ? stringarg /* use start pos rather than pos() */
2532 : (sv && (mg = mg_find_mglob(sv)) && mg->mg_len >= 0)
25fdce4a
FC
2533 /* Defined pos(): */
2534 ? strbeg + MgBYTEPOS(mg, sv, strbeg, strend-strbeg)
fef7148b
DM
2535 : strbeg; /* pos() not defined; use start of string */
2536
2537 DEBUG_GPOS_r(PerlIO_printf(Perl_debug_log,
7b0eb0b8 2538 "GPOS ganch set to strbeg[%"IVdf"]\n", (IV)(reginfo->ganch - strbeg)));
fef7148b 2539
03c83e26
DM
2540 /* in the presence of \G, we may need to start looking earlier in
2541 * the string than the suggested start point of stringarg:
0b2c2a84 2542 * if prog->gofs is set, then that's a known, fixed minimum
03c83e26
DM
2543 * offset, such as
2544 * /..\G/: gofs = 2
2545 * /ab|c\G/: gofs = 1
2546 * or if the minimum offset isn't known, then we have to go back
2547 * to the start of the string, e.g. /w+\G/
2548 */
2bfbe302 2549
8e1490ee 2550 if (prog->intflags & PREGf_ANCH_GPOS) {
2bfbe302
DM
2551 startpos = reginfo->ganch - prog->gofs;
2552 if (startpos <
2553 ((flags & REXEC_FAIL_ON_UNDERFLOW) ? stringarg : strbeg))
2554 {
2555 DEBUG_r(PerlIO_printf(Perl_debug_log,
2556 "fail: ganch-gofs before earliest possible start\n"));
2557 return 0;
2558 }
2559 }
2560 else if (prog->gofs) {
b342a604
DM
2561 if (startpos - prog->gofs < strbeg)
2562 startpos = strbeg;
2563 else
2564 startpos -= prog->gofs;
03c83e26 2565 }
58430ea8 2566 else if (prog->intflags & PREGf_GPOS_FLOAT)
b342a604 2567 startpos = strbeg;
03c83e26
DM
2568 }
2569
2570 minlen = prog->minlen;
b342a604 2571 if ((startpos + minlen) > strend || startpos < strbeg) {
03c83e26
DM
2572 DEBUG_r(PerlIO_printf(Perl_debug_log,
2573 "Regex match can't succeed, so not even tried\n"));
2574 return 0;
2575 }
2576
63a3746a
DM
2577 /* at the end of this function, we'll do a LEAVE_SCOPE(oldsave),
2578 * which will call destuctors to reset PL_regmatch_state, free higher
2579 * PL_regmatch_slabs, and clean up regmatch_info_aux and
2580 * regmatch_info_aux_eval */
2581
2582 oldsave = PL_savestack_ix;
2583
dfa77d06
DM
2584 s = startpos;
2585
e322109a 2586 if ((prog->extflags & RXf_USE_INTUIT)
7fadf4a7
DM
2587 && !(flags & REXEC_CHECKED))
2588 {
dfa77d06 2589 s = re_intuit_start(rx, sv, strbeg, startpos, strend,
7fadf4a7 2590 flags, NULL);
dfa77d06 2591 if (!s)
7fadf4a7
DM
2592 return 0;
2593
e322109a 2594 if (prog->extflags & RXf_CHECK_ALL) {
7fadf4a7
DM
2595 /* we can match based purely on the result of INTUIT.
2596 * Set up captures etc just for $& and $-[0]
2597 * (an intuit-only match wont have $1,$2,..) */
2598 assert(!prog->nparens);
d5e7783a
DM
2599
2600 /* s/// doesn't like it if $& is earlier than where we asked it to
2601 * start searching (which can happen on something like /.\G/) */
2602 if ( (flags & REXEC_FAIL_ON_UNDERFLOW)
2603 && (s < stringarg))
2604 {
2605 /* this should only be possible under \G */
58430ea8 2606 assert(prog->intflags & PREGf_GPOS_SEEN);
d5e7783a
DM
2607 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
2608 "matched, but failing for REXEC_FAIL_ON_UNDERFLOW\n"));
2609 goto phooey;
2610 }
2611
7fadf4a7
DM
2612 /* match via INTUIT shouldn't have any captures.
2613 * Let @-, @+, $^N know */
2614 prog->lastparen = prog->lastcloseparen = 0;
2615 RX_MATCH_UTF8_set(rx, utf8_target);
3ff69bd6
DM
2616 prog->offs[0].start = s - strbeg;
2617 prog->offs[0].end = utf8_target
2618 ? (char*)utf8_hop((U8*)s, prog->minlenret) - strbeg
2619 : s - strbeg + prog->minlenret;
7fadf4a7 2620 if ( !(flags & REXEC_NOT_FIRST) )
749f4950 2621 S_reg_set_capture_string(aTHX_ rx,
7fadf4a7
DM
2622 strbeg, strend,
2623 sv, flags, utf8_target);
2624
7fadf4a7
DM
2625 return 1;
2626 }
2627 }
2628
6c3fea77 2629 multiline = prog->extflags & RXf_PMf_MULTILINE;
1de06328 2630
dfa77d06 2631 if (strend - s < (minlen+(prog->check_offset_min<0?prog->check_offset_min:0))) {
a3621e74 2632 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
a72c7584
JH
2633 "String too short [regexec_flags]...\n"));
2634 goto phooey;
1aa99e6b 2635 }
1de06328 2636
6eb5f6b9 2637 /* Check validity of program. */
f8fc2ecf 2638 if (UCHARAT(progi->program) != REG_MAGIC) {
6eb5f6b9
JH
2639 Perl_croak(aTHX_ "corrupted regexp program");
2640 }
2641
1738e041 2642 RX_MATCH_TAINTED_off(rx);
ab4e48c1 2643 RX_MATCH_UTF8_set(rx, utf8_target);
1738e041 2644
6c3fea77
DM
2645 reginfo->prog = rx; /* Yes, sorry that this is confusing. */
2646 reginfo->intuit = 0;
2647 reginfo->is_utf8_target = cBOOL(utf8_target);
02d5137b
DM
2648 reginfo->is_utf8_pat = cBOOL(RX_UTF8(rx));
2649 reginfo->warned = FALSE;
9d9163fb 2650 reginfo->strbeg = strbeg;
02d5137b 2651 reginfo->sv = sv;
1cb48e53 2652 reginfo->poscache_maxiter = 0; /* not yet started a countdown */
220db18a 2653 reginfo->strend = strend;
6eb5f6b9 2654 /* see how far we have to get to not match where we matched before */
fe3974be 2655 reginfo->till = stringarg + minend;
6eb5f6b9 2656
60779a30 2657 if (prog->extflags & RXf_EVAL_SEEN && SvPADTMP(sv)) {
82c23608
FC
2658 /* SAVEFREESV, not sv_mortalcopy, as this SV must last until after
2659 S_cleanup_regmatch_info_aux has executed (registered by
2660 SAVEDESTRUCTOR_X below). S_cleanup_regmatch_info_aux modifies
2661 magic belonging to this SV.
2662 Not newSVsv, either, as it does not COW.
2663 */
2664 reginfo->sv = newSV(0);
4cba5ac0 2665 SvSetSV_nosteal(reginfo->sv, sv);
82c23608
FC
2666 SAVEFREESV(reginfo->sv);
2667 }
2668
331b2dcc
DM
2669 /* reserve next 2 or 3 slots in PL_regmatch_state:
2670 * slot N+0: may currently be in use: skip it
2671 * slot N+1: use for regmatch_info_aux struct
2672 * slot N+2: use for regmatch_info_aux_eval struct if we have (?{})'s
2673 * slot N+3: ready for use by regmatch()
2674 */
bf2039a9 2675
331b2dcc
DM
2676 {
2677 regmatch_state *old_regmatch_state;
2678 regmatch_slab *old_regmatch_slab;
2679 int i, max = (prog->extflags & RXf_EVAL_SEEN) ? 2 : 1;
2680
2681 /* on first ever match, allocate first slab */
2682 if (!PL_regmatch_slab) {
2683 Newx(PL_regmatch_slab, 1, regmatch_slab);
2684 PL_regmatch_slab->prev = NULL;
2685 PL_regmatch_slab->next = NULL;
2686 PL_regmatch_state = SLAB_FIRST(PL_regmatch_slab);
2687 }
bf2039a9 2688
331b2dcc
DM
2689 old_regmatch_state = PL_regmatch_state;
2690 old_regmatch_slab = PL_regmatch_slab;
bf2039a9 2691
331b2dcc
DM
2692 for (i=0; i <= max; i++) {
2693 if (i == 1)
2694 reginfo->info_aux = &(PL_regmatch_state->u.info_aux);
2695 else if (i ==2)
2696 reginfo->info_aux_eval =
2697 reginfo->info_aux->info_aux_eval =
2698 &(PL_regmatch_state->u.info_aux_eval);
bf2039a9 2699
331b2dcc
DM
2700 if (++PL_regmatch_state > SLAB_LAST(PL_regmatch_slab))
2701 PL_regmatch_state = S_push_slab(aTHX);
2702 }
bf2039a9 2703
331b2dcc
DM
2704 /* note initial PL_regmatch_state position; at end of match we'll
2705 * pop back to there and free any higher slabs */
bf2039a9 2706
331b2dcc
DM
2707 reginfo->info_aux->old_regmatch_state = old_regmatch_state;
2708 reginfo->info_aux->old_regmatch_slab = old_regmatch_slab;
2ac8ff4b 2709 reginfo->info_aux->poscache = NULL;
bf2039a9 2710
331b2dcc 2711 SAVEDESTRUCTOR_X(S_cleanup_regmatch_info_aux, reginfo->info_aux);
bf2039a9 2712
331b2dcc
DM
2713 if ((prog->extflags & RXf_EVAL_SEEN))
2714 S_setup_eval_state(aTHX_ reginfo);
2715 else
2716 reginfo->info_aux_eval = reginfo->info_aux->info_aux_eval = NULL;
bf2039a9 2717 }
d3aa529c 2718
6eb5f6b9 2719 /* If there is a "must appear" string, look for it. */
6eb5f6b9 2720
288b8c02 2721 if (PL_curpm && (PM_GETRE(PL_curpm) == rx)) {
e9105d30
GG
2722 /* We have to be careful. If the previous successful match
2723 was from this regex we don't want a subsequent partially
2724 successful match to clobber the old results.
2725 So when we detect this possibility we add a swap buffer
d8da0584
KW
2726 to the re, and switch the buffer each match. If we fail,
2727 we switch it back; otherwise we leave it swapped.
e9105d30
GG
2728 */
2729 swap = prog->offs;
2730 /* do we need a save destructor here for eval dies? */
2731 Newxz(prog->offs, (prog->nparens + 1), regexp_paren_pair);
495f47a5
DM
2732 DEBUG_BUFFERS_r(PerlIO_printf(Perl_debug_log,
2733 "rex=0x%"UVxf" saving offs: orig=0x%"UVxf" new=0x%"UVxf"\n",
2734 PTR2UV(prog),
2735 PTR2UV(swap),
2736 PTR2UV(prog->offs)
2737 ));
c74340f9 2738 }
6eb5f6b9
JH
2739
2740 /* Simplest case: anchored match need be tried only once. */
d3d47aac 2741 /* [unless only anchor is MBOL - implying multiline is set] */
8e1490ee 2742 if (prog->intflags & (PREGf_ANCH & ~PREGf_ANCH_GPOS)) {
3542935d 2743 if (s == startpos && regtry(reginfo, &s))
6eb5f6b9 2744 goto got_it;
8e1490ee 2745 else if (multiline || (prog->intflags & (PREGf_IMPLICIT | PREGf_ANCH_MBOL))) /* XXXX SBOL? */
6eb5f6b9
JH
2746 {
2747 char *end;
2748
2749 if (minlen)
2750 dontbother = minlen - 1;
1aa99e6b 2751 end = HOP3c(strend, -dontbother, strbeg) - 1;
6eb5f6b9 2752 /* for multiline we only have to try after newlines */
33b8afdf 2753 if (prog->check_substr || prog->check_utf8) {
92f3d482
YO
2754 /* because of the goto we can not easily reuse the macros for bifurcating the
2755 unicode/non-unicode match modes here like we do elsewhere - demerphq */
2756 if (utf8_target) {
2757 if (s == startpos)
2758 goto after_try_utf8;
2759 while (1) {
02d5137b 2760 if (regtry(reginfo, &s)) {
92f3d482
YO
2761 goto got_it;
2762 }
2763 after_try_utf8:
2764 if (s > end) {
2765 goto phooey;
2766 }
2767 if (prog->extflags & RXf_USE_INTUIT) {
52a21eb3
DM
2768 s = re_intuit_start(rx, sv, strbeg,
2769 s + UTF8SKIP(s), strend, flags, NULL);
92f3d482
YO
2770 if (!s) {
2771 goto phooey;
2772 }
2773 }
2774 else {
2775 s += UTF8SKIP(s);
2776 }
2777 }
2778 } /* end search for check string in unicode */
2779 else {
2780 if (s == startpos) {
2781 goto after_try_latin;
2782 }
2783 while (1) {
02d5137b 2784 if (regtry(reginfo, &s)) {
92f3d482
YO
2785 goto got_it;
2786 }
2787 after_try_latin:
2788 if (s > end) {
2789 goto phooey;
2790 }
2791 if (prog->extflags & RXf_USE_INTUIT) {
52a21eb3
DM
2792 s = re_intuit_start(rx, sv, strbeg,
2793 s + 1, strend, flags, NULL);
92f3d482
YO
2794 if (!s) {
2795 goto phooey;
2796 }
2797 }
2798 else {
2799 s++;
2800 }
2801 }
2802 } /* end search for check string in latin*/
2803 } /* end search for check string */
2804 else { /* search for newline */
2805 if (s > startpos) {
2806 /*XXX: The s-- is almost definitely wrong here under unicode - demeprhq*/
6eb5f6b9 2807 s--;
92f3d482 2808 }
21eede78
YO
2809 /* We can use a more efficient search as newlines are the same in unicode as they are in latin */
2810 while (s <= end) { /* note it could be possible to match at the end of the string */
6eb5f6b9 2811 if (*s++ == '\n') { /* don't need PL_utf8skip here */
02d5137b 2812 if (regtry(reginfo, &s))
6eb5f6b9
JH
2813 goto got_it;
2814 }
92f3d482
YO
2815 }
2816 } /* end search for newline */
2817 } /* end anchored/multiline check string search */
6eb5f6b9 2818 goto phooey;
a8430a8b 2819 } else if (prog->intflags & PREGf_ANCH_GPOS)
f9f4320a 2820 {
a8430a8b
YO
2821 /* PREGf_ANCH_GPOS should never be true if PREGf_GPOS_SEEN is not true */
2822 assert(prog->intflags & PREGf_GPOS_SEEN);
2bfbe302
DM
2823 /* For anchored \G, the only position it can match from is
2824 * (ganch-gofs); we already set startpos to this above; if intuit
2825 * moved us on from there, we can't possibly succeed */
2826 assert(startpos == reginfo->ganch - prog->gofs);
2827 if (s == startpos && regtry(reginfo, &s))
6eb5f6b9
JH
2828 goto got_it;
2829 goto phooey;
2830 }
2831
2832 /* Messy cases: unanchored match. */
bbe252da 2833 if ((prog->anchored_substr || prog->anchored_utf8) && prog->intflags & PREGf_SKIP) {
6eb5f6b9 2834 /* we have /x+whatever/ */
984e6dd1 2835 /* it must be a one character string (XXXX Except is_utf8_pat?) */
33b8afdf 2836 char ch;
bf93d4cc
GS
2837#ifdef DEBUGGING
2838 int did_match = 0;
2839#endif
f2ed9b32 2840 if (utf8_target) {
7e0d5ad7
KW
2841 if (! prog->anchored_utf8) {
2842 to_utf8_substr(prog);
2843 }
2844 ch = SvPVX_const(prog->anchored_utf8)[0];
4cadc6a9 2845 REXEC_FBC_SCAN(
6eb5f6b9 2846 if (*s == ch) {
a3621e74 2847 DEBUG_EXECUTE_r( did_match = 1 );
02d5137b 2848 if (regtry(reginfo, &s)) goto got_it;
6eb5f6b9
JH
2849 s += UTF8SKIP(s);
2850 while (s < strend && *s == ch)
2851 s += UTF8SKIP(s);
2852 }
4cadc6a9 2853 );
7e0d5ad7 2854
6eb5f6b9
JH
2855 }
2856 else {
7e0d5ad7
KW
2857 if (! prog->anchored_substr) {
2858 if (! to_byte_substr(prog)) {
6b54ddc5 2859 NON_UTF8_TARGET_BUT_UTF8_REQUIRED(phooey);
7e0d5ad7
KW
2860 }
2861 }
2862 ch = SvPVX_const(prog->anchored_substr)[0];
4cadc6a9 2863 REXEC_FBC_SCAN(
6eb5f6b9 2864 if (*s == ch) {
a3621e74 2865 DEBUG_EXECUTE_r( did_match = 1 );
02d5137b 2866 if (regtry(reginfo, &s)) goto got_it;
6eb5f6b9
JH
2867 s++;
2868 while (s < strend && *s == ch)
2869 s++;
2870 }
4cadc6a9 2871 );
6eb5f6b9 2872 }
a3621e74 2873 DEBUG_EXECUTE_r(if (!did_match)
bf93d4cc 2874 PerlIO_printf(Perl_debug_log,
b7953727
JH
2875 "Did not find anchored character...\n")
2876 );
6eb5f6b9 2877 }
a0714e2c
SS
2878 else if (prog->anchored_substr != NULL
2879 || prog->anchored_utf8 != NULL
2880 || ((prog->float_substr != NULL || prog->float_utf8 != NULL)
33b8afdf
JH
2881 && prog->float_max_offset < strend - s)) {
2882 SV *must;
ea3daa5d
FC
2883 SSize_t back_max;
2884 SSize_t back_min;
33b8afdf 2885 char *last;
6eb5f6b9 2886 char *last1; /* Last position checked before */
bf93d4cc
GS
2887#ifdef DEBUGGING
2888 int did_match = 0;
2889#endif
33b8afdf 2890 if (prog->anchored_substr || prog->anchored_utf8) {
7e0d5ad7
KW
2891 if (utf8_target) {
2892 if (! prog->anchored_utf8) {
2893 to_utf8_substr(prog);
2894 }
2895 must = prog->anchored_utf8;
2896 }
2897 else {
2898 if (! prog->anchored_substr) {
2899 if (! to_byte_substr(prog)) {
6b54ddc5 2900 NON_UTF8_TARGET_BUT_UTF8_REQUIRED(phooey);
7e0d5ad7
KW
2901 }
2902 }
2903 must = prog->anchored_substr;
2904 }
33b8afdf
JH
2905 back_max = back_min = prog->anchored_offset;
2906 } else {
7e0d5ad7
KW
2907 if (utf8_target) {
2908 if (! prog->float_utf8) {
2909 to_utf8_substr(prog);
2910 }
2911 must = prog->float_utf8;
2912 }
2913 else {
2914 if (! prog->float_substr) {
2915 if (! to_byte_substr(prog)) {
6b54ddc5 2916 NON_UTF8_TARGET_BUT_UTF8_REQUIRED(phooey);
7e0d5ad7
KW
2917 }
2918 }
2919 must = prog->float_substr;
2920 }
33b8afdf
JH
2921 back_max = prog->float_max_offset;
2922 back_min = prog->float_min_offset;
2923 }
1de06328 2924
1de06328
YO
2925 if (back_min<0) {
2926 last = strend;
2927 } else {
2928 last = HOP3c(strend, /* Cannot start after this */
ea3daa5d 2929 -(SSize_t)(CHR_SVLEN(must)
1de06328
YO
2930 - (SvTAIL(must) != 0) + back_min), strbeg);
2931 }
9d9163fb 2932 if (s > reginfo->strbeg)
6eb5f6b9
JH
2933 last1 = HOPc(s, -1);
2934 else
2935 last1 = s - 1; /* bogus */
2936
a0288114 2937 /* XXXX check_substr already used to find "s", can optimize if
6eb5f6b9 2938 check_substr==must. */
bf05793b 2939 dontbother = 0;
6eb5f6b9
JH
2940 strend = HOPc(strend, -dontbother);
2941 while ( (s <= last) &&
e50d57d4 2942 (s = fbm_instr((unsigned char*)HOP4c(s, back_min, strbeg, strend),
9041c2e3 2943 (unsigned char*)strend, must,
c33e64f0 2944 multiline ? FBMrf_MULTILINE : 0)) ) {
a3621e74 2945 DEBUG_EXECUTE_r( did_match = 1 );
6eb5f6b9
JH
2946 if (HOPc(s, -back_max) > last1) {
2947 last1 = HOPc(s, -back_min);
2948 s = HOPc(s, -back_max);
2949 }
2950 else {
9d9163fb
DM
2951 char * const t = (last1 >= reginfo->strbeg)
2952 ? HOPc(last1, 1) : last1 + 1;
6eb5f6b9
JH
2953
2954 last1 = HOPc(s, -back_min);
52657f30 2955 s = t;
6eb5f6b9 2956 }
f2ed9b32 2957 if (utf8_target) {
6eb5f6b9 2958 while (s <= last1) {
02d5137b 2959 if (regtry(reginfo, &s))
6eb5f6b9 2960 goto got_it;
7016d6eb
DM
2961 if (s >= last1) {
2962 s++; /* to break out of outer loop */
2963 break;
2964 }
2965 s += UTF8SKIP(s);
6eb5f6b9
JH
2966 }
2967 }
2968 else {
2969 while (s <= last1) {
02d5137b 2970 if (regtry(reginfo, &s))
6eb5f6b9
JH
2971 goto got_it;
2972 s++;
2973 }
2974 }
2975 }
ab3bbdeb 2976 DEBUG_EXECUTE_r(if (!did_match) {
f2ed9b32 2977 RE_PV_QUOTED_DECL(quoted, utf8_target, PERL_DEBUG_PAD_ZERO(0),
ab3bbdeb
YO
2978 SvPVX_const(must), RE_SV_DUMPLEN(must), 30);
2979 PerlIO_printf(Perl_debug_log, "Did not find %s substr %s%s...\n",
33b8afdf 2980 ((must == prog->anchored_substr || must == prog->anchored_utf8)
bf93d4cc 2981 ? "anchored" : "floating"),
ab3bbdeb
YO
2982 quoted, RE_SV_TAIL(must));
2983 });
6eb5f6b9
JH
2984 goto phooey;
2985 }
f8fc2ecf 2986 else if ( (c = progi->regstclass) ) {
f14c76ed 2987 if (minlen) {
f8fc2ecf 2988 const OPCODE op = OP(progi->regstclass);
66e933ab 2989 /* don't bother with what can't match */
786e8c11 2990 if (PL_regkind[op] != EXACT && op != CANY && PL_regkind[op] != TRIE)
f14c76ed
RGS
2991 strend = HOPc(strend, -(minlen - 1));
2992 }
a3621e74 2993 DEBUG_EXECUTE_r({
be8e71aa 2994 SV * const prop = sv_newmortal();
8b9781c9 2995 regprop(prog, prop, c, reginfo, NULL);
0df25f3d 2996 {
f2ed9b32 2997 RE_PV_QUOTED_DECL(quoted,utf8_target,PERL_DEBUG_PAD_ZERO(1),
ab3bbdeb 2998 s,strend-s,60);
0df25f3d 2999 PerlIO_printf(Perl_debug_log,
1c8f8eb1 3000 "Matching stclass %.*s against %s (%d bytes)\n",
e4f74956 3001 (int)SvCUR(prop), SvPVX_const(prop),
ab3bbdeb 3002 quoted, (int)(strend - s));
0df25f3d 3003 }
ffc61ed2 3004 });
f9176b44 3005 if (find_byclass(prog, c, s, strend, reginfo))
6eb5f6b9 3006 goto got_it;
07be1b83 3007 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log, "Contradicts stclass... [regexec_flags]\n"));
d6a28714
JH
3008 }
3009 else {
3010 dontbother = 0;
a0714e2c 3011 if (prog->float_substr != NULL || prog->float_utf8 != NULL) {
33b8afdf 3012 /* Trim the end. */
6af40bd7 3013 char *last= NULL;
33b8afdf 3014 SV* float_real;
c33e64f0
FC
3015 STRLEN len;
3016 const char *little;
33b8afdf 3017
7e0d5ad7
KW
3018 if (utf8_target) {
3019 if (! prog->float_utf8) {
3020 to_utf8_substr(prog);
3021 }
3022 float_real = prog->float_utf8;
3023 }
3024 else {
3025 if (! prog->float_substr) {
3026 if (! to_byte_substr(prog)) {
6b54ddc5 3027 NON_UTF8_TARGET_BUT_UTF8_REQUIRED(phooey);
7e0d5ad7
KW
3028 }
3029 }
3030 float_real = prog->float_substr;
3031 }
d6a28714 3032
c33e64f0
FC
3033 little = SvPV_const(float_real, len);
3034 if (SvTAIL(float_real)) {
7f18ad16
KW
3035 /* This means that float_real contains an artificial \n on
3036 * the end due to the presence of something like this:
3037 * /foo$/ where we can match both "foo" and "foo\n" at the
3038 * end of the string. So we have to compare the end of the
3039 * string first against the float_real without the \n and
3040 * then against the full float_real with the string. We
3041 * have to watch out for cases where the string might be
3042 * smaller than the float_real or the float_real without
3043 * the \n. */
1a13b075
YO
3044 char *checkpos= strend - len;
3045 DEBUG_OPTIMISE_r(
3046 PerlIO_printf(Perl_debug_log,
3047 "%sChecking for float_real.%s\n",
3048 PL_colors[4], PL_colors[5]));
3049 if (checkpos + 1 < strbeg) {
7f18ad16
KW
3050 /* can't match, even if we remove the trailing \n
3051 * string is too short to match */
1a13b075
YO
3052 DEBUG_EXECUTE_r(
3053 PerlIO_printf(Perl_debug_log,
3054 "%sString shorter than required trailing substring, cannot match.%s\n",
3055 PL_colors[4], PL_colors[5]));
3056 goto phooey;
3057 } else if (memEQ(checkpos + 1, little, len - 1)) {
7f18ad16
KW
3058 /* can match, the end of the string matches without the
3059 * "\n" */
1a13b075
YO
3060 last = checkpos + 1;
3061 } else if (checkpos < strbeg) {
7f18ad16
KW
3062 /* cant match, string is too short when the "\n" is
3063 * included */
1a13b075
YO
3064 DEBUG_EXECUTE_r(
3065 PerlIO_printf(Perl_debug_log,
3066 "%sString does not contain required trailing substring, cannot match.%s\n",
3067 PL_colors[4], PL_colors[5]));
3068 goto phooey;
3069 } else if (!multiline) {
7f18ad16
KW
3070 /* non multiline match, so compare with the "\n" at the
3071 * end of the string */
1a13b075
YO
3072 if (memEQ(checkpos, little, len)) {
3073 last= checkpos;
3074 } else {
3075 DEBUG_EXECUTE_r(
3076 PerlIO_printf(Perl_debug_log,
3077 "%sString does not contain required trailing substring, cannot match.%s\n",
3078 PL_colors[4], PL_colors[5]));
3079 goto phooey;
3080 }
3081 } else {
7f18ad16
KW
3082 /* multiline match, so we have to search for a place
3083 * where the full string is located */
d6a28714 3084 goto find_last;
1a13b075 3085 }
c33e64f0 3086 } else {
d6a28714 3087 find_last:
9041c2e3 3088 if (len)
d6a28714 3089 last = rninstr(s, strend, little, little + len);
b8c5462f 3090 else
a0288114 3091 last = strend; /* matching "$" */
b8c5462f 3092 }
6af40bd7 3093 if (!last) {
7f18ad16
KW
3094 /* at one point this block contained a comment which was
3095 * probably incorrect, which said that this was a "should not
3096 * happen" case. Even if it was true when it was written I am
3097 * pretty sure it is not anymore, so I have removed the comment
3098 * and replaced it with this one. Yves */
6bda09f9
YO
3099 DEBUG_EXECUTE_r(
3100 PerlIO_printf(Perl_debug_log,
b729e729
YO
3101 "%sString does not contain required substring, cannot match.%s\n",
3102 PL_colors[4], PL_colors[5]
6af40bd7
YO
3103 ));
3104 goto phooey;
bf93d4cc 3105 }
d6a28714
JH
3106 dontbother = strend - last + prog->float_min_offset;
3107 }
3108 if (minlen && (dontbother < minlen))
3109 dontbother = minlen - 1;
3110 strend -= dontbother; /* this one's always in bytes! */
3111 /* We don't know much -- general case. */
f2ed9b32 3112 if (utf8_target) {
d6a28714 3113 for (;;) {
02d5137b 3114 if (regtry(reginfo, &s))
d6a28714
JH
3115 goto got_it;
3116 if (s >= strend)
3117 break;
b8c5462f 3118 s += UTF8SKIP(s);
d6a28714
JH
3119 };
3120 }
3121 else {
3122 do {
02d5137b 3123 if (regtry(reginfo, &s))
d6a28714
JH
3124 goto got_it;
3125 } while (s++ < strend);
3126 }
3127 }
3128
3129 /* Failure. */
3130 goto phooey;
3131
3132got_it:
d5e7783a
DM
3133 /* s/// doesn't like it if $& is earlier than where we asked it to
3134 * start searching (which can happen on something like /.\G/) */
3135 if ( (flags & REXEC_FAIL_ON_UNDERFLOW)
3136 && (prog->offs[0].start < stringarg - strbeg))
3137 {
3138 /* this should only be possible under \G */
58430ea8 3139 assert(prog->intflags & PREGf_GPOS_SEEN);
d5e7783a
DM
3140 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
3141 "matched, but failing for REXEC_FAIL_ON_UNDERFLOW\n"));
3142 goto phooey;
3143 }
3144
495f47a5
DM
3145 DEBUG_BUFFERS_r(
3146 if (swap)
3147 PerlIO_printf(Perl_debug_log,
3148 "rex=0x%"UVxf" freeing offs: 0x%"UVxf"\n",
3149 PTR2UV(prog),
3150 PTR2UV(swap)
3151 );
3152 );
e9105d30 3153 Safefree(swap);
d6a28714 3154
bf2039a9
DM
3155 /* clean up; this will trigger destructors that will free all slabs
3156 * above the current one, and cleanup the regmatch_info_aux
3157 * and regmatch_info_aux_eval sructs */
8adc0f72 3158
006f26b2
DM
3159 LEAVE_SCOPE(oldsave);
3160
5daac39c
NC
3161 if (RXp_PAREN_NAMES(prog))
3162 (void)hv_iterinit(RXp_PAREN_NAMES(prog));
d6a28714
JH
3163
3164 /* make sure $`, $&, $', and $digit will work later */
60165aa4 3165 if ( !(flags & REXEC_NOT_FIRST) )
749f4950 3166 S_reg_set_capture_string(aTHX_ rx,
60165aa4
DM
3167 strbeg, reginfo->strend,
3168 sv, flags, utf8_target);
9041c2e3 3169
d6a28714
JH
3170 return 1;
3171
3172phooey:
a3621e74 3173 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log, "%sMatch failed%s\n",
e4584336 3174 PL_colors[4], PL_colors[5]));
8adc0f72 3175
bf2039a9
DM
3176 /* clean up; this will trigger destructors that will free all slabs
3177 * above the current one, and cleanup the regmatch_info_aux
3178 * and regmatch_info_aux_eval sructs */
8adc0f72 3179
006f26b2
DM
3180 LEAVE_SCOPE(oldsave);
3181
e9105d30 3182 if (swap) {
c74340f9 3183 /* we failed :-( roll it back */
495f47a5
DM
3184 DEBUG_BUFFERS_r(PerlIO_printf(Perl_debug_log,
3185 "rex=0x%"UVxf" rolling back offs: freeing=0x%"UVxf" restoring=0x%"UVxf"\n",
3186 PTR2UV(prog),
3187 PTR2UV(prog->offs),
3188 PTR2UV(swap)
3189 ));
e9105d30
GG
3190 Safefree(prog->offs);
3191 prog->offs = swap;
3192 }
d6a28714
JH
3193 return 0;
3194}
3195
6bda09f9 3196
b3d298be 3197/* Set which rex is pointed to by PL_reg_curpm, handling ref counting.
ec43f78b 3198 * Do inc before dec, in case old and new rex are the same */
baa60164 3199#define SET_reg_curpm(Re2) \
bf2039a9 3200 if (reginfo->info_aux_eval) { \
ec43f78b
DM
3201 (void)ReREFCNT_inc(Re2); \
3202 ReREFCNT_dec(PM_GETRE(PL_reg_curpm)); \
3203 PM_SETRE((PL_reg_curpm), (Re2)); \
3204 }
3205
3206
d6a28714
JH
3207/*
3208 - regtry - try match at specific point
3209 */
3210STATIC I32 /* 0 failure, 1 success */
f73aaa43 3211S_regtry(pTHX_ regmatch_info *reginfo, char **startposp)
d6a28714 3212{
d6a28714 3213 CHECKPOINT lastcp;
288b8c02 3214 REGEXP *const rx = reginfo->prog;
8d919b0a 3215 regexp *const prog = ReANY(rx);
99a90e59 3216 SSize_t result;
f8fc2ecf 3217 RXi_GET_DECL(prog,progi);
a3621e74 3218 GET_RE_DEBUG_FLAGS_DECL;
7918f24d
NC
3219
3220 PERL_ARGS_ASSERT_REGTRY;
3221
24b23f37 3222 reginfo->cutpoint=NULL;
d6a28714 3223
9d9163fb 3224 prog->offs[0].start = *startposp - reginfo->strbeg;
d6a28714 3225 prog->lastparen = 0;
03994de8 3226 prog->lastcloseparen = 0;
d6a28714
JH
3227
3228 /* XXXX What this code is doing here?!!! There should be no need
b93070ed 3229 to do this again and again, prog->lastparen should take care of
3dd2943c 3230 this! --ilya*/
dafc8851
JH
3231
3232 /* Tests pat.t#187 and split.t#{13,14} seem to depend on this code.
3233 * Actually, the code in regcppop() (which Ilya may be meaning by
b93070ed 3234 * prog->lastparen), is not needed at all by the test suite
225593e1
DM
3235 * (op/regexp, op/pat, op/split), but that code is needed otherwise
3236 * this erroneously leaves $1 defined: "1" =~ /^(?:(\d)x)?\d$/
3237 * Meanwhile, this code *is* needed for the
daf18116
JH
3238 * above-mentioned test suite tests to succeed. The common theme
3239 * on those tests seems to be returning null fields from matches.
225593e1 3240 * --jhi updated by dapm */
dafc8851 3241#if 1
d6a28714 3242 if (prog->nparens) {
b93070ed 3243 regexp_paren_pair *pp = prog->offs;
eb578fdb 3244 I32 i;
b93070ed 3245 for (i = prog->nparens; i > (I32)prog->lastparen; i--) {
f0ab9afb
NC
3246 ++pp;
3247 pp->start = -1;
3248 pp->end = -1;
d6a28714
JH
3249 }
3250 }
dafc8851 3251#endif
02db2b7b 3252 REGCP_SET(lastcp);
f73aaa43
DM
3253 result = regmatch(reginfo, *startposp, progi->program + 1);
3254 if (result != -1) {
3255 prog->offs[0].end = result;
d6a28714
JH
3256 return 1;
3257 }
24b23f37 3258 if (reginfo->cutpoint)
f73aaa43 3259 *startposp= reginfo->cutpoint;
02db2b7b 3260 REGCP_UNWIND(lastcp);
d6a28714
JH
3261 return 0;
3262}
3263
02db2b7b 3264
8ba1375e
MJD
3265#define sayYES goto yes
3266#define sayNO goto no
262b90c4 3267#define sayNO_SILENT goto no_silent
8ba1375e 3268
f9f4320a
YO
3269/* we dont use STMT_START/END here because it leads to
3270 "unreachable code" warnings, which are bogus, but distracting. */
3271#define CACHEsayNO \
c476f425 3272 if (ST.cache_mask) \
2ac8ff4b 3273 reginfo->info_aux->poscache[ST.cache_offset] |= ST.cache_mask; \
f9f4320a 3274 sayNO
3298f257 3275
a3621e74 3276/* this is used to determine how far from the left messages like
265c4333
YO
3277 'failed...' are printed. It should be set such that messages
3278 are inline with the regop output that created them.
a3621e74 3279*/
265c4333 3280#define REPORT_CODE_OFF 32
a3621e74
YO
3281
3282
40a82448
DM
3283#define CHRTEST_UNINIT -1001 /* c1/c2 haven't been calculated yet */
3284#define CHRTEST_VOID -1000 /* the c1/c2 "next char" test should be skipped */
79a2a0e8
KW
3285#define CHRTEST_NOT_A_CP_1 -999
3286#define CHRTEST_NOT_A_CP_2 -998
9e137952 3287
5d9a96ca
DM
3288/* grab a new slab and return the first slot in it */
3289
3290STATIC regmatch_state *
3291S_push_slab(pTHX)
3292{
a35a87e7 3293#if PERL_VERSION < 9 && !defined(PERL_CORE)
54df2634
NC
3294 dMY_CXT;
3295#endif
5d9a96ca
DM
3296 regmatch_slab *s = PL_regmatch_slab->next;
3297 if (!s) {
3298 Newx(s, 1, regmatch_slab);
3299 s->prev = PL_regmatch_slab;
3300 s->next = NULL;
3301 PL_regmatch_slab->next = s;
3302 }
3303 PL_regmatch_slab = s;
86545054 3304 return SLAB_FIRST(s);
5d9a96ca 3305}
5b47454d 3306
95b24440 3307
40a82448
DM
3308/* push a new state then goto it */
3309
4d5016e5
DM
3310#define PUSH_STATE_GOTO(state, node, input) \
3311 pushinput = input; \
40a82448
DM
3312 scan = node; \
3313 st->resume_state = state; \
3314 goto push_state;
3315
3316/* push a new state with success backtracking, then goto it */
3317
4d5016e5
DM
3318#define PUSH_YES_STATE_GOTO(state, node, input) \
3319 pushinput = input; \
40a82448
DM
3320 scan = node; \
3321 st->resume_state = state; \
3322 goto push_yes_state;
3323
aa283a38 3324
aa283a38 3325
4d5016e5 3326
d6a28714 3327/*
95b24440 3328
bf1f174e
DM
3329regmatch() - main matching routine
3330
3331This is basically one big switch statement in a loop. We execute an op,
3332set 'next' to point the next op, and continue. If we come to a point which
3333we may need to backtrack to on failure such as (A|B|C), we push a
3334backtrack state onto the backtrack stack. On failure, we pop the top
3335state, and re-enter the loop at the state indicated. If there are no more
3336states to pop, we return failure.
3337
3338Sometimes we also need to backtrack on success; for example /A+/, where
3339after successfully matching one A, we need to go back and try to
3340match another one; similarly for lookahead assertions: if the assertion
3341completes successfully, we backtrack to the state just before the assertion
3342and then carry on. In these cases, the pushed state is marked as
3343'backtrack on success too'. This marking is in fact done by a chain of
3344pointers, each pointing to the previous 'yes' state. On success, we pop to
3345the nearest yes state, discarding any intermediate failure-only states.
3346Sometimes a yes state is pushed just to force some cleanup code to be
3347called at the end of a successful match or submatch; e.g. (??{$re}) uses
3348it to free the inner regex.
3349
3350Note that failure backtracking rewinds the cursor position, while
3351success backtracking leaves it alone.
3352
3353A pattern is complete when the END op is executed, while a subpattern
3354such as (?=foo) is complete when the SUCCESS op is executed. Both of these
3355ops trigger the "pop to last yes state if any, otherwise return true"
3356behaviour.
3357
3358A common convention in this function is to use A and B to refer to the two
3359subpatterns (or to the first nodes thereof) in patterns like /A*B/: so A is
3360the subpattern to be matched possibly multiple times, while B is the entire
3361rest of the pattern. Variable and state names reflect this convention.
3362
3363The states in the main switch are the union of ops and failure/success of
3364substates associated with with that op. For example, IFMATCH is the op
3365that does lookahead assertions /(?=A)B/ and so the IFMATCH state means
3366'execute IFMATCH'; while IFMATCH_A is a state saying that we have just
3367successfully matched A and IFMATCH_A_fail is a state saying that we have
3368just failed to match A. Resume states always come in pairs. The backtrack
3369state we push is marked as 'IFMATCH_A', but when that is popped, we resume
3370at IFMATCH_A or IFMATCH_A_fail, depending on whether we are backtracking
3371on success or failure.
3372
3373The struct that holds a backtracking state is actually a big union, with
3374one variant for each major type of op. The variable st points to the
3375top-most backtrack struct. To make the code clearer, within each
3376block of code we #define ST to alias the relevant union.
3377
3378Here's a concrete example of a (vastly oversimplified) IFMATCH
3379implementation:
3380
3381 switch (state) {
3382 ....
3383
3384#define ST st->u.ifmatch
3385
3386 case IFMATCH: // we are executing the IFMATCH op, (?=A)B
3387 ST.foo = ...; // some state we wish to save
95b24440 3388 ...
bf1f174e
DM
3389 // push a yes backtrack state with a resume value of
3390 // IFMATCH_A/IFMATCH_A_fail, then continue execution at the
3391 // first node of A:
4d5016e5 3392 PUSH_YES_STATE_GOTO(IFMATCH_A, A, newinput);
bf1f174e
DM
3393 // NOTREACHED
3394
3395 case IFMATCH_A: // we have successfully executed A; now continue with B
3396 next = B;
3397 bar = ST.foo; // do something with the preserved value
3398 break;
3399
3400 case IFMATCH_A_fail: // A failed, so the assertion failed
3401 ...; // do some housekeeping, then ...
3402 sayNO; // propagate the failure
3403
3404#undef ST
95b24440 3405
bf1f174e
DM
3406 ...
3407 }
95b24440 3408
bf1f174e
DM
3409For any old-timers reading this who are familiar with the old recursive
3410approach, the code above is equivalent to:
95b24440 3411
bf1f174e
DM
3412 case IFMATCH: // we are executing the IFMATCH op, (?=A)B
3413 {
3414 int foo = ...
95b24440 3415 ...
bf1f174e
DM
3416 if (regmatch(A)) {
3417 next = B;
3418 bar = foo;
3419 break;
95b24440 3420 }
bf1f174e
DM
3421 ...; // do some housekeeping, then ...
3422 sayNO; // propagate the failure
95b24440 3423 }
bf1f174e
DM
3424
3425The topmost backtrack state, pointed to by st, is usually free. If you
3426want to claim it, populate any ST.foo fields in it with values you wish to
3427save, then do one of
3428
4d5016e5
DM
3429 PUSH_STATE_GOTO(resume_state, node, newinput);
3430 PUSH_YES_STATE_GOTO(resume_state, node, newinput);
bf1f174e
DM
3431
3432which sets that backtrack state's resume value to 'resume_state', pushes a
3433new free entry to the top of the backtrack stack, then goes to 'node'.
3434On backtracking, the free slot is popped, and the saved state becomes the
3435new free state. An ST.foo field in this new top state can be temporarily
3436accessed to retrieve values, but once the main loop is re-entered, it
3437becomes available for reuse.
3438
3439Note that the depth of the backtrack stack constantly increases during the
3440left-to-right execution of the pattern, rather than going up and down with
3441the pattern nesting. For example the stack is at its maximum at Z at the
3442end of the pattern, rather than at X in the following:
3443
3444 /(((X)+)+)+....(Y)+....Z/
3445
3446The only exceptions to this are lookahead/behind assertions and the cut,
3447(?>A), which pop all the backtrack states associated with A before
3448continuing.
3449
486ec47a 3450Backtrack state structs are allocated in slabs of about 4K in size.
bf1f174e
DM
3451PL_regmatch_state and st always point to the currently active state,
3452and PL_regmatch_slab points to the slab currently containing
3453PL_regmatch_state. The first time regmatch() is called, the first slab is
3454allocated, and is never freed until interpreter destruction. When the slab
3455is full, a new one is allocated and chained to the end. At exit from
3456regmatch(), slabs allocated since entry are freed.
3457
3458*/
95b24440 3459
40a82448 3460
5bc10b2c 3461#define DEBUG_STATE_pp(pp) \
265c4333 3462 DEBUG_STATE_r({ \
baa60164 3463 DUMP_EXEC_POS(locinput, scan, utf8_target); \
5bc10b2c 3464 PerlIO_printf(Perl_debug_log, \
5d458dd8 3465 " %*s"pp" %s%s%s%s%s\n", \
5bc10b2c 3466 depth*2, "", \
baa60164 3467 PL_reg_name[st->resume_state], \
5d458dd8
YO
3468 ((st==yes_state||st==mark_state) ? "[" : ""), \
3469 ((st==yes_state) ? "Y" : ""), \
3470 ((st==mark_state) ? "M" : ""), \
3471 ((st==yes_state||st==mark_state) ? "]" : "") \
3472 ); \
265c4333 3473 });
5bc10b2c 3474
40a82448 3475
3dab1dad 3476#define REG_NODE_NUM(x) ((x) ? (int)((x)-prog) : -1)
95b24440 3477
3df15adc 3478#ifdef DEBUGGING
5bc10b2c 3479
ab3bbdeb 3480STATIC void
f2ed9b32 3481S_debug_start_match(pTHX_ const REGEXP *prog, const bool utf8_target,
ab3bbdeb
YO
3482 const char *start, const char *end, const char *blurb)
3483{
efd26800 3484 const bool utf8_pat = RX_UTF8(prog) ? 1 : 0;
7918f24d
NC
3485
3486 PERL_ARGS_ASSERT_DEBUG_START_MATCH;
3487
ab3bbdeb
YO
3488 if (!PL_colorset)
3489 reginitcolors();
3490 {
3491 RE_PV_QUOTED_DECL(s0, utf8_pat, PERL_DEBUG_PAD_ZERO(0),
d2c6dc5e 3492 RX_PRECOMP_const(prog), RX_PRELEN(prog), 60);
ab3bbdeb 3493
f2ed9b32 3494 RE_PV_QUOTED_DECL(s1, utf8_target, PERL_DEBUG_PAD_ZERO(1),
ab3bbdeb
YO
3495 start, end - start, 60);
3496
3497 PerlIO_printf(Perl_debug_log,
3498 "%s%s REx%s %s against %s\n",
3499 PL_colors[4], blurb, PL_colors[5], s0, s1);
3500
f2ed9b32 3501 if (utf8_target||utf8_pat)
1de06328
YO
3502 PerlIO_printf(Perl_debug_log, "UTF-8 %s%s%s...\n",
3503 utf8_pat ? "pattern" : "",
f2ed9b32
KW
3504 utf8_pat && utf8_target ? " and " : "",
3505 utf8_target ? "string" : ""
ab3bbdeb
YO
3506 );
3507 }
3508}
3df15adc
YO
3509
3510STATIC void
786e8c11
YO
3511S_dump_exec_pos(pTHX_ const char *locinput,
3512 const regnode *scan,
3513 const char *loc_regeol,
3514 const char *loc_bostr,
3515 const char *loc_reg_starttry,
f2ed9b32 3516 const bool utf8_target)
07be1b83 3517{
786e8c11 3518 const int docolor = *PL_colors[0] || *PL_colors[2] || *PL_colors[4];
07be1b83 3519 const int taill = (docolor ? 10 : 7); /* 3 chars for "> <" */
786e8c11 3520 int l = (loc_regeol - locinput) > taill ? taill : (loc_regeol - locinput);
07be1b83
YO
3521 /* The part of the string before starttry has one color
3522 (pref0_len chars), between starttry and current
3523 position another one (pref_len - pref0_len chars),
3524 after the current position the third one.
3525 We assume that pref0_len <= pref_len, otherwise we
3526 decrease pref0_len. */
786e8c11
YO
3527 int pref_len = (locinput - loc_bostr) > (5 + taill) - l
3528 ? (5 + taill) - l : locinput - loc_bostr;
07be1b83
YO
3529 int pref0_len;
3530
7918f24d
NC
3531 PERL_ARGS_ASSERT_DUMP_EXEC_POS;
3532
f2ed9b32 3533 while (utf8_target && UTF8_IS_CONTINUATION(*(U8*)(locinput - pref_len)))
07be1b83 3534 pref_len++;
786e8c11
YO
3535 pref0_len = pref_len - (locinput - loc_reg_starttry);
3536 if (l + pref_len < (5 + taill) && l < loc_regeol - locinput)
3537 l = ( loc_regeol - locinput > (5 + taill) - pref_len
3538 ? (5 + taill) - pref_len : loc_regeol - locinput);
f2ed9b32 3539 while (utf8_target && UTF8_IS_CONTINUATION(*(U8*)(locinput + l)))
07be1b83
YO
3540 l--;
3541 if (pref0_len < 0)
3542 pref0_len = 0;
3543 if (pref0_len > pref_len)
3544 pref0_len = pref_len;
3545 {