1// Copyright (c) 2005, Google Inc. 2// All rights reserved. 3// 4// Redistribution and use in source and binary forms, with or without 5// modification, are permitted provided that the following conditions are 6// met: 7// 8// * Redistributions of source code must retain the above copyright 9// notice, this list of conditions and the following disclaimer. 10// * Redistributions in binary form must reproduce the above 11// copyright notice, this list of conditions and the following disclaimer 12// in the documentation and/or other materials provided with the 13// distribution. 14// * Neither the name of Google Inc. nor the names of its 15// contributors may be used to endorse or promote products derived from 16// this software without specific prior written permission. 17// 18// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 19// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 20// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 21// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 22// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 23// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 24// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 28// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29// 30// Author: Sanjay Ghemawat 31// Support for PCRE_XXX modifiers added by Giuseppe Maxia, July 2005 32 33#ifndef _PCRECPP_H 34#define _PCRECPP_H 35 36// C++ interface to the pcre regular-expression library. RE supports 37// Perl-style regular expressions (with extensions like \d, \w, \s, 38// ...). 39// 40// ----------------------------------------------------------------------- 41// REGEXP SYNTAX: 42// 43// This module is part of the pcre library and hence supports its syntax 44// for regular expressions. 45// 46// The syntax is pretty similar to Perl's. For those not familiar 47// with Perl's regular expressions, here are some examples of the most 48// commonly used extensions: 49// 50// "hello (\\w+) world" -- \w matches a "word" character 51// "version (\\d+)" -- \d matches a digit 52// "hello\\s+world" -- \s matches any whitespace character 53// "\\b(\\w+)\\b" -- \b matches empty string at a word boundary 54// "(?i)hello" -- (?i) turns on case-insensitive matching 55// "/\\*(.*?)\\*/" -- .*? matches . minimum no. of times possible 56// 57// ----------------------------------------------------------------------- 58// MATCHING INTERFACE: 59// 60// The "FullMatch" operation checks that supplied text matches a 61// supplied pattern exactly. 62// 63// Example: successful match 64// pcrecpp::RE re("h.*o"); 65// re.FullMatch("hello"); 66// 67// Example: unsuccessful match (requires full match): 68// pcrecpp::RE re("e"); 69// !re.FullMatch("hello"); 70// 71// Example: creating a temporary RE object: 72// pcrecpp::RE("h.*o").FullMatch("hello"); 73// 74// You can pass in a "const char*" or a "string" for "text". The 75// examples below tend to use a const char*. 76// 77// You can, as in the different examples above, store the RE object 78// explicitly in a variable or use a temporary RE object. The 79// examples below use one mode or the other arbitrarily. Either 80// could correctly be used for any of these examples. 81// 82// ----------------------------------------------------------------------- 83// MATCHING WITH SUB-STRING EXTRACTION: 84// 85// You can supply extra pointer arguments to extract matched subpieces. 86// 87// Example: extracts "ruby" into "s" and 1234 into "i" 88// int i; 89// string s; 90// pcrecpp::RE re("(\\w+):(\\d+)"); 91// re.FullMatch("ruby:1234", &s, &i); 92// 93// Example: does not try to extract any extra sub-patterns 94// re.FullMatch("ruby:1234", &s); 95// 96// Example: does not try to extract into NULL 97// re.FullMatch("ruby:1234", NULL, &i); 98// 99// Example: integer overflow causes failure 100// !re.FullMatch("ruby:1234567891234", NULL, &i); 101// 102// Example: fails because there aren't enough sub-patterns: 103// !pcrecpp::RE("\\w+:\\d+").FullMatch("ruby:1234", &s); 104// 105// Example: fails because string cannot be stored in integer 106// !pcrecpp::RE("(.*)").FullMatch("ruby", &i); 107// 108// The provided pointer arguments can be pointers to any scalar numeric 109// type, or one of 110// string (matched piece is copied to string) 111// StringPiece (StringPiece is mutated to point to matched piece) 112// T (where "bool T::ParseFrom(const char*, int)" exists) 113// NULL (the corresponding matched sub-pattern is not copied) 114// 115// CAVEAT: An optional sub-pattern that does not exist in the matched 116// string is assigned the empty string. Therefore, the following will 117// return false (because the empty string is not a valid number): 118// int number; 119// pcrecpp::RE::FullMatch("abc", "[a-z]+(\\d+)?", &number); 120// 121// ----------------------------------------------------------------------- 122// DO_MATCH 123// 124// The matching interface supports at most 16 arguments per call. 125// If you need more, consider using the more general interface 126// pcrecpp::RE::DoMatch(). See pcrecpp.h for the signature for DoMatch. 127// 128// ----------------------------------------------------------------------- 129// PARTIAL MATCHES 130// 131// You can use the "PartialMatch" operation when you want the pattern 132// to match any substring of the text. 133// 134// Example: simple search for a string: 135// pcrecpp::RE("ell").PartialMatch("hello"); 136// 137// Example: find first number in a string: 138// int number; 139// pcrecpp::RE re("(\\d+)"); 140// re.PartialMatch("x*100 + 20", &number); 141// assert(number == 100); 142// 143// ----------------------------------------------------------------------- 144// UTF-8 AND THE MATCHING INTERFACE: 145// 146// By default, pattern and text are plain text, one byte per character. 147// The UTF8 flag, passed to the constructor, causes both pattern 148// and string to be treated as UTF-8 text, still a byte stream but 149// potentially multiple bytes per character. In practice, the text 150// is likelier to be UTF-8 than the pattern, but the match returned 151// may depend on the UTF8 flag, so always use it when matching 152// UTF8 text. E.g., "." will match one byte normally but with UTF8 153// set may match up to three bytes of a multi-byte character. 154// 155// Example: 156// pcrecpp::RE_Options options; 157// options.set_utf8(); 158// pcrecpp::RE re(utf8_pattern, options); 159// re.FullMatch(utf8_string); 160// 161// Example: using the convenience function UTF8(): 162// pcrecpp::RE re(utf8_pattern, pcrecpp::UTF8()); 163// re.FullMatch(utf8_string); 164// 165// NOTE: The UTF8 option is ignored if pcre was not configured with the 166// --enable-utf8 flag. 167// 168// ----------------------------------------------------------------------- 169// PASSING MODIFIERS TO THE REGULAR EXPRESSION ENGINE 170// 171// PCRE defines some modifiers to change the behavior of the regular 172// expression engine. 173// The C++ wrapper defines an auxiliary class, RE_Options, as a vehicle 174// to pass such modifiers to a RE class. 175// 176// Currently, the following modifiers are supported 177// 178// modifier description Perl corresponding 179// 180// PCRE_CASELESS case insensitive match /i 181// PCRE_MULTILINE multiple lines match /m 182// PCRE_DOTALL dot matches newlines /s 183// PCRE_DOLLAR_ENDONLY $ matches only at end N/A 184// PCRE_EXTRA strict escape parsing N/A 185// PCRE_EXTENDED ignore whitespaces /x 186// PCRE_UTF8 handles UTF8 chars built-in 187// PCRE_UNGREEDY reverses * and *? N/A 188// PCRE_NO_AUTO_CAPTURE disables matching parens N/A (*) 189// 190// (For a full account on how each modifier works, please check the 191// PCRE API reference manual). 192// 193// (*) Both Perl and PCRE allow non matching parentheses by means of the 194// "?:" modifier within the pattern itself. e.g. (?:ab|cd) does not 195// capture, while (ab|cd) does. 196// 197// For each modifier, there are two member functions whose name is made 198// out of the modifier in lowercase, without the "PCRE_" prefix. For 199// instance, PCRE_CASELESS is handled by 200// bool caseless(), 201// which returns true if the modifier is set, and 202// RE_Options & set_caseless(bool), 203// which sets or unsets the modifier. 204// 205// Moreover, PCRE_EXTRA_MATCH_LIMIT can be accessed through the 206// set_match_limit() and match_limit() member functions. 207// Setting match_limit to a non-zero value will limit the executation of 208// pcre to keep it from doing bad things like blowing the stack or taking 209// an eternity to return a result. A value of 5000 is good enough to stop 210// stack blowup in a 2MB thread stack. Setting match_limit to zero will 211// disable match limiting. Alternately, you can set match_limit_recursion() 212// which uses PCRE_EXTRA_MATCH_LIMIT_RECURSION to limit how much pcre 213// recurses. match_limit() caps the number of matches pcre does; 214// match_limit_recrusion() caps the depth of recursion. 215// 216// Normally, to pass one or more modifiers to a RE class, you declare 217// a RE_Options object, set the appropriate options, and pass this 218// object to a RE constructor. Example: 219// 220// RE_options opt; 221// opt.set_caseless(true); 222// 223// if (RE("HELLO", opt).PartialMatch("hello world")) ... 224// 225// RE_options has two constructors. The default constructor takes no 226// arguments and creates a set of flags that are off by default. 227// 228// The optional parameter 'option_flags' is to facilitate transfer 229// of legacy code from C programs. This lets you do 230// RE(pattern, RE_Options(PCRE_CASELESS|PCRE_MULTILINE)).PartialMatch(str); 231// 232// But new code is better off doing 233// RE(pattern, 234// RE_Options().set_caseless(true).set_multiline(true)).PartialMatch(str); 235// (See below) 236// 237// If you are going to pass one of the most used modifiers, there are some 238// convenience functions that return a RE_Options class with the 239// appropriate modifier already set: 240// CASELESS(), UTF8(), MULTILINE(), DOTALL(), EXTENDED() 241// 242// If you need to set several options at once, and you don't want to go 243// through the pains of declaring a RE_Options object and setting several 244// options, there is a parallel method that give you such ability on the 245// fly. You can concatenate several set_xxxxx member functions, since each 246// of them returns a reference to its class object. e.g.: to pass 247// PCRE_CASELESS, PCRE_EXTENDED, and PCRE_MULTILINE to a RE with one 248// statement, you may write 249// 250// RE(" ^ xyz \\s+ .* blah$", RE_Options() 251// .set_caseless(true) 252// .set_extended(true) 253// .set_multiline(true)).PartialMatch(sometext); 254// 255// ----------------------------------------------------------------------- 256// SCANNING TEXT INCREMENTALLY 257// 258// The "Consume" operation may be useful if you want to repeatedly 259// match regular expressions at the front of a string and skip over 260// them as they match. This requires use of the "StringPiece" type, 261// which represents a sub-range of a real string. Like RE, StringPiece 262// is defined in the pcrecpp namespace. 263// 264// Example: read lines of the form "var = value" from a string. 265// string contents = ...; // Fill string somehow 266// pcrecpp::StringPiece input(contents); // Wrap in a StringPiece 267// 268// string var; 269// int value; 270// pcrecpp::RE re("(\\w+) = (\\d+)\n"); 271// while (re.Consume(&input, &var, &value)) { 272// ...; 273// } 274// 275// Each successful call to "Consume" will set "var/value", and also 276// advance "input" so it points past the matched text. 277// 278// The "FindAndConsume" operation is similar to "Consume" but does not 279// anchor your match at the beginning of the string. For example, you 280// could extract all words from a string by repeatedly calling 281// pcrecpp::RE("(\\w+)").FindAndConsume(&input, &word) 282// 283// ----------------------------------------------------------------------- 284// PARSING HEX/OCTAL/C-RADIX NUMBERS 285// 286// By default, if you pass a pointer to a numeric value, the 287// corresponding text is interpreted as a base-10 number. You can 288// instead wrap the pointer with a call to one of the operators Hex(), 289// Octal(), or CRadix() to interpret the text in another base. The 290// CRadix operator interprets C-style "0" (base-8) and "0x" (base-16) 291// prefixes, but defaults to base-10. 292// 293// Example: 294// int a, b, c, d; 295// pcrecpp::RE re("(.*) (.*) (.*) (.*)"); 296// re.FullMatch("100 40 0100 0x40", 297// pcrecpp::Octal(&a), pcrecpp::Hex(&b), 298// pcrecpp::CRadix(&c), pcrecpp::CRadix(&d)); 299// will leave 64 in a, b, c, and d. 300// 301// ----------------------------------------------------------------------- 302// REPLACING PARTS OF STRINGS 303// 304// You can replace the first match of "pattern" in "str" with 305// "rewrite". Within "rewrite", backslash-escaped digits (\1 to \9) 306// can be used to insert text matching corresponding parenthesized 307// group from the pattern. \0 in "rewrite" refers to the entire 308// matching text. E.g., 309// 310// string s = "yabba dabba doo"; 311// pcrecpp::RE("b+").Replace("d", &s); 312// 313// will leave "s" containing "yada dabba doo". The result is true if 314// the pattern matches and a replacement occurs, or false otherwise. 315// 316// GlobalReplace() is like Replace(), except that it replaces all 317// occurrences of the pattern in the string with the rewrite. 318// Replacements are not subject to re-matching. E.g., 319// 320// string s = "yabba dabba doo"; 321// pcrecpp::RE("b+").GlobalReplace("d", &s); 322// 323// will leave "s" containing "yada dada doo". It returns the number 324// of replacements made. 325// 326// Extract() is like Replace(), except that if the pattern matches, 327// "rewrite" is copied into "out" (an additional argument) with 328// substitutions. The non-matching portions of "text" are ignored. 329// Returns true iff a match occurred and the extraction happened 330// successfully. If no match occurs, the string is left unaffected. 331 332 333#include <string> 334#include <pcre.h> 335#include <pcrecpparg.h> // defines the Arg class 336// This isn't technically needed here, but we include it 337// anyway so folks who include pcrecpp.h don't have to. 338#include <pcre_stringpiece.h> 339 340namespace pcrecpp { 341 342#define PCRE_SET_OR_CLEAR(b, o) \ 343 if (b) all_options_ |= (o); else all_options_ &= ~(o); \ 344 return *this 345 346#define PCRE_IS_SET(o) \ 347 (all_options_ & o) == o 348 349/***** Compiling regular expressions: the RE class *****/ 350 351// RE_Options allow you to set options to be passed along to pcre, 352// along with other options we put on top of pcre. 353// Only 9 modifiers, plus match_limit and match_limit_recursion, 354// are supported now. 355class PCRECPP_EXP_DEFN RE_Options { 356 public: 357 // constructor 358 RE_Options() : match_limit_(0), match_limit_recursion_(0), all_options_(0) {} 359 360 // alternative constructor. 361 // To facilitate transfer of legacy code from C programs 362 // 363 // This lets you do 364 // RE(pattern, RE_Options(PCRE_CASELESS|PCRE_MULTILINE)).PartialMatch(str); 365 // But new code is better off doing 366 // RE(pattern, 367 // RE_Options().set_caseless(true).set_multiline(true)).PartialMatch(str); 368 RE_Options(int option_flags) : match_limit_(0), match_limit_recursion_(0), 369 all_options_(option_flags) {} 370 // we're fine with the default destructor, copy constructor, etc. 371 372 // accessors and mutators 373 int match_limit() const { return match_limit_; }; 374 RE_Options &set_match_limit(int limit) { 375 match_limit_ = limit; 376 return *this; 377 } 378 379 int match_limit_recursion() const { return match_limit_recursion_; }; 380 RE_Options &set_match_limit_recursion(int limit) { 381 match_limit_recursion_ = limit; 382 return *this; 383 } 384 385 bool caseless() const { 386 return PCRE_IS_SET(PCRE_CASELESS); 387 } 388 RE_Options &set_caseless(bool x) { 389 PCRE_SET_OR_CLEAR(x, PCRE_CASELESS); 390 } 391 392 bool multiline() const { 393 return PCRE_IS_SET(PCRE_MULTILINE); 394 } 395 RE_Options &set_multiline(bool x) { 396 PCRE_SET_OR_CLEAR(x, PCRE_MULTILINE); 397 } 398 399 bool dotall() const { 400 return PCRE_IS_SET(PCRE_DOTALL); 401 } 402 RE_Options &set_dotall(bool x) { 403 PCRE_SET_OR_CLEAR(x, PCRE_DOTALL); 404 } 405 406 bool extended() const { 407 return PCRE_IS_SET(PCRE_EXTENDED); 408 } 409 RE_Options &set_extended(bool x) { 410 PCRE_SET_OR_CLEAR(x, PCRE_EXTENDED); 411 } 412 413 bool dollar_endonly() const { 414 return PCRE_IS_SET(PCRE_DOLLAR_ENDONLY); 415 } 416 RE_Options &set_dollar_endonly(bool x) { 417 PCRE_SET_OR_CLEAR(x, PCRE_DOLLAR_ENDONLY); 418 } 419 420 bool extra() const { 421 return PCRE_IS_SET(PCRE_EXTRA); 422 } 423 RE_Options &set_extra(bool x) { 424 PCRE_SET_OR_CLEAR(x, PCRE_EXTRA); 425 } 426 427 bool ungreedy() const { 428 return PCRE_IS_SET(PCRE_UNGREEDY); 429 } 430 RE_Options &set_ungreedy(bool x) { 431 PCRE_SET_OR_CLEAR(x, PCRE_UNGREEDY); 432 } 433 434 bool utf8() const { 435 return PCRE_IS_SET(PCRE_UTF8); 436 } 437 RE_Options &set_utf8(bool x) { 438 PCRE_SET_OR_CLEAR(x, PCRE_UTF8); 439 } 440 441 bool no_auto_capture() const { 442 return PCRE_IS_SET(PCRE_NO_AUTO_CAPTURE); 443 } 444 RE_Options &set_no_auto_capture(bool x) { 445 PCRE_SET_OR_CLEAR(x, PCRE_NO_AUTO_CAPTURE); 446 } 447 448 RE_Options &set_all_options(int opt) { 449 all_options_ = opt; 450 return *this; 451 } 452 int all_options() const { 453 return all_options_ ; 454 } 455 456 // TODO: add other pcre flags 457 458 private: 459 int match_limit_; 460 int match_limit_recursion_; 461 int all_options_; 462}; 463 464// These functions return some common RE_Options 465static inline RE_Options UTF8() { 466 return RE_Options().set_utf8(true); 467} 468 469static inline RE_Options CASELESS() { 470 return RE_Options().set_caseless(true); 471} 472static inline RE_Options MULTILINE() { 473 return RE_Options().set_multiline(true); 474} 475 476static inline RE_Options DOTALL() { 477 return RE_Options().set_dotall(true); 478} 479 480static inline RE_Options EXTENDED() { 481 return RE_Options().set_extended(true); 482} 483 484// Interface for regular expression matching. Also corresponds to a 485// pre-compiled regular expression. An "RE" object is safe for 486// concurrent use by multiple threads. 487class PCRECPP_EXP_DEFN RE { 488 public: 489 // We provide implicit conversions from strings so that users can 490 // pass in a string or a "const char*" wherever an "RE" is expected. 491 RE(const string& pat) { Init(pat, NULL); } 492 RE(const string& pat, const RE_Options& option) { Init(pat, &option); } 493 RE(const char* pat) { Init(pat, NULL); } 494 RE(const char* pat, const RE_Options& option) { Init(pat, &option); } 495 RE(const unsigned char* pat) { 496 Init(reinterpret_cast<const char*>(pat), NULL); 497 } 498 RE(const unsigned char* pat, const RE_Options& option) { 499 Init(reinterpret_cast<const char*>(pat), &option); 500 } 501 502 // Copy constructor & assignment - note that these are expensive 503 // because they recompile the expression. 504 RE(const RE& re) { Init(re.pattern_, &re.options_); } 505 const RE& operator=(const RE& re) { 506 if (this != &re) { 507 Cleanup(); 508 509 // This is the code that originally came from Google 510 // Init(re.pattern_.c_str(), &re.options_); 511 512 // This is the replacement from Ari Pollak 513 Init(re.pattern_, &re.options_); 514 } 515 return *this; 516 } 517 518 519 ~RE(); 520 521 // The string specification for this RE. E.g. 522 // RE re("ab*c?d+"); 523 // re.pattern(); // "ab*c?d+" 524 const string& pattern() const { return pattern_; } 525 526 // If RE could not be created properly, returns an error string. 527 // Else returns the empty string. 528 const string& error() const { return *error_; } 529 530 /***** The useful part: the matching interface *****/ 531 532 // This is provided so one can do pattern.ReplaceAll() just as 533 // easily as ReplaceAll(pattern-text, ....) 534 535 bool FullMatch(const StringPiece& text, 536 const Arg& ptr1 = no_arg, 537 const Arg& ptr2 = no_arg, 538 const Arg& ptr3 = no_arg, 539 const Arg& ptr4 = no_arg, 540 const Arg& ptr5 = no_arg, 541 const Arg& ptr6 = no_arg, 542 const Arg& ptr7 = no_arg, 543 const Arg& ptr8 = no_arg, 544 const Arg& ptr9 = no_arg, 545 const Arg& ptr10 = no_arg, 546 const Arg& ptr11 = no_arg, 547 const Arg& ptr12 = no_arg, 548 const Arg& ptr13 = no_arg, 549 const Arg& ptr14 = no_arg, 550 const Arg& ptr15 = no_arg, 551 const Arg& ptr16 = no_arg) const; 552 553 bool PartialMatch(const StringPiece& text, 554 const Arg& ptr1 = no_arg, 555 const Arg& ptr2 = no_arg, 556 const Arg& ptr3 = no_arg, 557 const Arg& ptr4 = no_arg, 558 const Arg& ptr5 = no_arg, 559 const Arg& ptr6 = no_arg, 560 const Arg& ptr7 = no_arg, 561 const Arg& ptr8 = no_arg, 562 const Arg& ptr9 = no_arg, 563 const Arg& ptr10 = no_arg, 564 const Arg& ptr11 = no_arg, 565 const Arg& ptr12 = no_arg, 566 const Arg& ptr13 = no_arg, 567 const Arg& ptr14 = no_arg, 568 const Arg& ptr15 = no_arg, 569 const Arg& ptr16 = no_arg) const; 570 571 bool Consume(StringPiece* input, 572 const Arg& ptr1 = no_arg, 573 const Arg& ptr2 = no_arg, 574 const Arg& ptr3 = no_arg, 575 const Arg& ptr4 = no_arg, 576 const Arg& ptr5 = no_arg, 577 const Arg& ptr6 = no_arg, 578 const Arg& ptr7 = no_arg, 579 const Arg& ptr8 = no_arg, 580 const Arg& ptr9 = no_arg, 581 const Arg& ptr10 = no_arg, 582 const Arg& ptr11 = no_arg, 583 const Arg& ptr12 = no_arg, 584 const Arg& ptr13 = no_arg, 585 const Arg& ptr14 = no_arg, 586 const Arg& ptr15 = no_arg, 587 const Arg& ptr16 = no_arg) const; 588 589 bool FindAndConsume(StringPiece* input, 590 const Arg& ptr1 = no_arg, 591 const Arg& ptr2 = no_arg, 592 const Arg& ptr3 = no_arg, 593 const Arg& ptr4 = no_arg, 594 const Arg& ptr5 = no_arg, 595 const Arg& ptr6 = no_arg, 596 const Arg& ptr7 = no_arg, 597 const Arg& ptr8 = no_arg, 598 const Arg& ptr9 = no_arg, 599 const Arg& ptr10 = no_arg, 600 const Arg& ptr11 = no_arg, 601 const Arg& ptr12 = no_arg, 602 const Arg& ptr13 = no_arg, 603 const Arg& ptr14 = no_arg, 604 const Arg& ptr15 = no_arg, 605 const Arg& ptr16 = no_arg) const; 606 607 bool Replace(const StringPiece& rewrite, 608 string *str) const; 609 610 int GlobalReplace(const StringPiece& rewrite, 611 string *str) const; 612 613 bool Extract(const StringPiece &rewrite, 614 const StringPiece &text, 615 string *out) const; 616 617 // Escapes all potentially meaningful regexp characters in 618 // 'unquoted'. The returned string, used as a regular expression, 619 // will exactly match the original string. For example, 620 // 1.5-2.0? 621 // may become: 622 // 1\.5\-2\.0\? 623 // Note QuoteMeta behaves the same as perl's QuoteMeta function, 624 // *except* that it escapes the NUL character (\0) as backslash + 0, 625 // rather than backslash + NUL. 626 static string QuoteMeta(const StringPiece& unquoted); 627 628 629 /***** Generic matching interface *****/ 630 631 // Type of match (TODO: Should be restructured as part of RE_Options) 632 enum Anchor { 633 UNANCHORED, // No anchoring 634 ANCHOR_START, // Anchor at start only 635 ANCHOR_BOTH // Anchor at start and end 636 }; 637 638 // General matching routine. Stores the length of the match in 639 // "*consumed" if successful. 640 bool DoMatch(const StringPiece& text, 641 Anchor anchor, 642 int* consumed, 643 const Arg* const* args, int n) const; 644 645 // Return the number of capturing subpatterns, or -1 if the 646 // regexp wasn't valid on construction. 647 int NumberOfCapturingGroups() const; 648 649 // The default value for an argument, to indicate the end of the argument 650 // list. This must be used only in optional argument defaults. It should NOT 651 // be passed explicitly. Some people have tried to use it like this: 652 // 653 // FullMatch(x, y, &z, no_arg, &w); 654 // 655 // This is a mistake, and will not work. 656 static Arg no_arg; 657 658 private: 659 660 void Init(const string& pattern, const RE_Options* options); 661 void Cleanup(); 662 663 // Match against "text", filling in "vec" (up to "vecsize" * 2/3) with 664 // pairs of integers for the beginning and end positions of matched 665 // text. The first pair corresponds to the entire matched text; 666 // subsequent pairs correspond, in order, to parentheses-captured 667 // matches. Returns the number of pairs (one more than the number of 668 // the last subpattern with a match) if matching was successful 669 // and zero if the match failed. 670 // I.e. for RE("(foo)|(bar)|(baz)") it will return 2, 3, and 4 when matching 671 // against "foo", "bar", and "baz" respectively. 672 // When matching RE("(foo)|hello") against "hello", it will return 1. 673 // But the values for all subpattern are filled in into "vec". 674 int TryMatch(const StringPiece& text, 675 int startpos, 676 Anchor anchor, 677 bool empty_ok, 678 int *vec, 679 int vecsize) const; 680 681 // Append the "rewrite" string, with backslash subsitutions from "text" 682 // and "vec", to string "out". 683 bool Rewrite(string *out, 684 const StringPiece& rewrite, 685 const StringPiece& text, 686 int *vec, 687 int veclen) const; 688 689 // internal implementation for DoMatch 690 bool DoMatchImpl(const StringPiece& text, 691 Anchor anchor, 692 int* consumed, 693 const Arg* const args[], 694 int n, 695 int* vec, 696 int vecsize) const; 697 698 // Compile the regexp for the specified anchoring mode 699 pcre* Compile(Anchor anchor); 700 701 string pattern_; 702 RE_Options options_; 703 pcre* re_full_; // For full matches 704 pcre* re_partial_; // For partial matches 705 const string* error_; // Error indicator (or points to empty string) 706}; 707 708} // namespace pcrecpp 709 710#endif /* _PCRECPP_H */ 711