// Copyright 2003-2009 The RE2 Authors. All Rights Reserved.

// Use of this source code is governed by a BSD-style

// license that can be found in the LICENSE file.

#ifndef RE2_RE2_H_

#define RE2_RE2_H_

// C++ interface to the re2 regular-expression library.

// RE2 supports Perl-style regular expressions (with extensions like

// \d, \w, \s, ...).

//

// -----------------------------------------------------------------------

// REGEXP SYNTAX:

//

// This module uses the re2 library and hence supports

// its syntax for regular expressions, which is similar to Perl's with

// some of the more complicated things thrown away. In particular,

// backreferences and generalized assertions are not available, nor is \Z.

//

// See https://github.com/google/re2/wiki/Syntax for the syntax

// supported by RE2, and a comparison with PCRE and PERL regexps.

//

// For those not familiar with Perl's regular expressions,

// here are some examples of the most commonly used extensions:

//

// "hello (\\w+) world" -- \w matches a "word" character

// "version (\\d+)" -- \d matches a digit

// "hello\\s+world" -- \s matches any whitespace character

// "\\b(\\w+)\\b" -- \b matches non-empty string at word boundary

// "(?i)hello" -- (?i) turns on case-insensitive matching

// "/\\*(.*?)\\*/" -- .*? matches . minimum no. of times possible

//

// The double backslashes are needed when writing C++ string literals.

// However, they should NOT be used when writing C++11 raw string literals:

//

// R"(hello (\w+) world)" -- \w matches a "word" character

// R"(version (\d+))" -- \d matches a digit

// R"(hello\s+world)" -- \s matches any whitespace character

// R"(\b(\w+)\b)" -- \b matches non-empty string at word boundary

// R"((?i)hello)" -- (?i) turns on case-insensitive matching

// R"(/\*(.*?)\*/)" -- .*? matches . minimum no. of times possible

//

// When using UTF-8 encoding, case-insensitive matching will perform

// simple case folding, not full case folding.

//

// -----------------------------------------------------------------------

// MATCHING INTERFACE:

//

// The "FullMatch" operation checks that supplied text matches a

// supplied pattern exactly.

//

// Example: successful match

// CHECK(RE2::FullMatch("hello", "h.*o"));

//

// Example: unsuccessful match (requires full match):

// CHECK(!RE2::FullMatch("hello", "e"));

//

// -----------------------------------------------------------------------

// UTF-8 AND THE MATCHING INTERFACE:

//

// By default, the pattern and input text are interpreted as UTF-8.

// The RE2::Latin1 option causes them to be interpreted as Latin-1.

//

// Example:

// CHECK(RE2::FullMatch(utf8_string, RE2(utf8_pattern)));

// CHECK(RE2::FullMatch(latin1_string, RE2(latin1_pattern, RE2::Latin1)));

//

// -----------------------------------------------------------------------

// MATCHING WITH SUBSTRING EXTRACTION:

//

// You can supply extra pointer arguments to extract matched substrings.

// On match failure, none of the pointees will have been modified.

// On match success, the substrings will be converted (as necessary) and

// their values will be assigned to their pointees until all conversions

// have succeeded or one conversion has failed.

// On conversion failure, the pointees will be in an indeterminate state

// because the caller has no way of knowing which conversion failed.

// However, conversion cannot fail for types like string and StringPiece

// that do not inspect the substring contents. Hence, in the common case

// where all of the pointees are of such types, failure is always due to

// match failure and thus none of the pointees will have been modified.

//

// Example: extracts "ruby" into "s" and 1234 into "i"

// int i;

// std::string s;

// CHECK(RE2::FullMatch("ruby:1234", "(\\w+):(\\d+)", &s, &i));

//

// Example: fails because string cannot be stored in integer

// CHECK(!RE2::FullMatch("ruby", "(.*)", &i));

//

// Example: fails because there aren't enough sub-patterns

// CHECK(!RE2::FullMatch("ruby:1234", "\\w+:\\d+", &s));

//

// Example: does not try to extract any extra sub-patterns

// CHECK(RE2::FullMatch("ruby:1234", "(\\w+):(\\d+)", &s));

//

// Example: does not try to extract into NULL

// CHECK(RE2::FullMatch("ruby:1234", "(\\w+):(\\d+)", NULL, &i));

//

// Example: integer overflow causes failure

// CHECK(!RE2::FullMatch("ruby:1234567891234", "\\w+:(\\d+)", &i));

//

// NOTE(rsc): Asking for substrings slows successful matches quite a bit.

// This may get a little faster in the future, but right now is slower

// than PCRE. On the other hand, failed matches run *very* fast (faster

// than PCRE), as do matches without substring extraction.

//

// -----------------------------------------------------------------------

// PARTIAL MATCHES

//

// You can use the "PartialMatch" operation when you want the pattern

// to match any substring of the text.

//

// Example: simple search for a string:

// CHECK(RE2::PartialMatch("hello", "ell"));

//

// Example: find first number in a string

// int number;

// CHECK(RE2::PartialMatch("x*100 + 20", "(\\d+)", &number));

// CHECK_EQ(number, 100);

//

// -----------------------------------------------------------------------

// PRE-COMPILED REGULAR EXPRESSIONS

//

// RE2 makes it easy to use any string as a regular expression, without

// requiring a separate compilation step.

//

// If speed is of the essence, you can create a pre-compiled "RE2"

// object from the pattern and use it multiple times. If you do so,

// you can typically parse text faster than with sscanf.

//

// Example: precompile pattern for faster matching:

// RE2 pattern("h.*o");

// while (ReadLine(&str)) {

// if (RE2::FullMatch(str, pattern)) ...;

// }

//

// -----------------------------------------------------------------------

// SCANNING TEXT INCREMENTALLY

//

// The "Consume" operation may be useful if you want to repeatedly

// match regular expressions at the front of a string and skip over

// them as they match. This requires use of the "StringPiece" type,

// which represents a sub-range of a real string.

//

// Example: read lines of the form "var = value" from a string.

// std::string contents = ...; // Fill string somehow

// StringPiece input(contents); // Wrap a StringPiece around it

//

// std::string var;

// int value;

// while (RE2::Consume(&input, "(\\w+) = (\\d+)\n", &var, &value)) {

// ...;

// }

//

// Each successful call to "Consume" will set "var/value", and also

// advance "input" so it points past the matched text. Note that if the

// regular expression matches an empty string, input will advance

// by 0 bytes. If the regular expression being used might match

// an empty string, the loop body must check for this case and either

// advance the string or break out of the loop.

//

// The "FindAndConsume" operation is similar to "Consume" but does not

// anchor your match at the beginning of the string. For example, you

// could extract all words from a string by repeatedly calling

// RE2::FindAndConsume(&input, "(\\w+)", &word)

//

// -----------------------------------------------------------------------

// USING VARIABLE NUMBER OF ARGUMENTS

//

// The above operations require you to know the number of arguments

// when you write the code. This is not always possible or easy (for

// example, the regular expression may be calculated at run time).

// You can use the "N" version of the operations when the number of

// match arguments are determined at run time.

//

// Example:

// const RE2::Arg* args[10];

// int n;

// // ... populate args with pointers to RE2::Arg values ...

// // ... set n to the number of RE2::Arg objects ...

// bool match = RE2::FullMatchN(input, pattern, args, n);

//

// The last statement is equivalent to

//

// bool match = RE2::FullMatch(input, pattern,

// *args[0], *args[1], ..., *args[n - 1]);

//

// -----------------------------------------------------------------------

// PARSING HEX/OCTAL/C-RADIX NUMBERS

//

// By default, if you pass a pointer to a numeric value, the

// corresponding text is interpreted as a base-10 number. You can

// instead wrap the pointer with a call to one of the operators Hex(),

// Octal(), or CRadix() to interpret the text in another base. The

// CRadix operator interprets C-style "0" (base-8) and "0x" (base-16)

// prefixes, but defaults to base-10.

//

// Example:

// int a, b, c, d;

// CHECK(RE2::FullMatch("100 40 0100 0x40", "(.*) (.*) (.*) (.*)",

// RE2::Octal(&a), RE2::Hex(&b), RE2::CRadix(&c), RE2::CRadix(&d));

// will leave 64 in a, b, c, and d.

#include <stddef.h>

#include <stdint.h>

#include <algorithm>

#include <map>

#include <mutex>

#include <string>

#include <type_traits>

#include <vector>

#if defined(__APPLE__)

#include <TargetConditionals.h>

#endif

#include "re2/stringpiece.h"

namespace re2 {

class Prog;

class Regexp;

} // namespace re2

namespace re2 {

// Interface for regular expression matching. Also corresponds to a

// pre-compiled regular expression. An "RE2" object is safe for

// concurrent use by multiple threads.

class RE2 {

public:

// We convert user-passed pointers into special Arg objects

class Arg;

class Options;

// Defined in set.h.

class Set;

enum ErrorCode {

NoError = 0,

// Unexpected error

ErrorInternal,

// Parse errors

ErrorBadEscape, // bad escape sequence

ErrorBadCharClass, // bad character class

ErrorBadCharRange, // bad character class range

ErrorMissingBracket, // missing closing ]

ErrorMissingParen, // missing closing )

ErrorUnexpectedParen, // unexpected closing )

ErrorTrailingBackslash, // trailing \ at end of regexp

ErrorRepeatArgument, // repeat argument missing, e.g. "*"

ErrorRepeatSize, // bad repetition argument

ErrorRepeatOp, // bad repetition operator

ErrorBadPerlOp, // bad perl operator

ErrorBadUTF8, // invalid UTF-8 in regexp

ErrorBadNamedCapture, // bad named capture group

ErrorPatternTooLarge // pattern too large (compile failed)

};

// Predefined common options.

// If you need more complicated things, instantiate

// an Option class, possibly passing one of these to

// the Option constructor, change the settings, and pass that

// Option class to the RE2 constructor.

enum CannedOptions {

DefaultOptions = 0,

Latin1, // treat input as Latin-1 (default UTF-8)

POSIX, // POSIX syntax, leftmost-longest match

Quiet // do not log about regexp parse errors

};

// Need to have the const char* and const std::string& forms for implicit

// conversions when passing string literals to FullMatch and PartialMatch.

// Otherwise the StringPiece form would be sufficient.

#ifndef SWIG

RE2(const char* pattern);

RE2(const std::string& pattern);

#endif

RE2(const StringPiece& pattern);

RE2(const StringPiece& pattern, const Options& options);

~RE2();

// Returns whether RE2 was created properly.

bool ok() const { return error_code() == NoError; }

// The string specification for this RE2. E.g.

// RE2 re("ab*c?d+");

// re.pattern(); // "ab*c?d+"

const std::string& pattern() const { return pattern_; }

// If RE2 could not be created properly, returns an error string.

// Else returns the empty string.

const std::string& error() const { return *error_; }

// If RE2 could not be created properly, returns an error code.

// Else returns RE2::NoError (== 0).

ErrorCode error_code() const { return error_code_; }

// If RE2 could not be created properly, returns the offending

// portion of the regexp.

const std::string& error_arg() const { return error_arg_; }

// Returns the program size, a very approximate measure of a regexp's "cost".

// Larger numbers are more expensive than smaller numbers.

int ProgramSize() const;

int ReverseProgramSize() const;

// If histogram is not null, outputs the program fanout

// as a histogram bucketed by powers of 2.

// Returns the number of the largest non-empty bucket.

int ProgramFanout(std::vector<int>* histogram) const;

int ReverseProgramFanout(std::vector<int>* histogram) const;

// Returns the underlying Regexp; not for general use.

// Returns entire_regexp_ so that callers don't need

// to know about prefix_ and prefix_foldcase_.

re2::Regexp* Regexp() const { return entire_regexp_; }

/***** The array-based matching interface ******/

// The functions here have names ending in 'N' and are used to implement

// the functions whose names are the prefix before the 'N'. It is sometimes

// useful to invoke them directly, but the syntax is awkward, so the 'N'-less

// versions should be preferred.

static bool FullMatchN(const StringPiece& text, const RE2& re,

const Arg* const args[], int n);

static bool PartialMatchN(const StringPiece& text, const RE2& re,

const Arg* const args[], int n);

static bool ConsumeN(StringPiece* input, const RE2& re,

const Arg* const args[], int n);

static bool FindAndConsumeN(StringPiece* input, const RE2& re,

const Arg* const args[], int n);

#ifndef SWIG

private:

template <typename F, typename SP>

static inline bool Apply(F f, SP sp, const RE2& re) {

return f(sp, re, NULL, 0);

}

template <typename F, typename SP, typename... A>

static inline bool Apply(F f, SP sp, const RE2& re, const A&... a) {

const Arg* const args[] = {&a...};

const int n = sizeof...(a);

return f(sp, re, args, n);

}

public:

// In order to allow FullMatch() et al. to be called with a varying number

// of arguments of varying types, we use two layers of variadic templates.

// The first layer constructs the temporary Arg objects. The second layer

// (above) constructs the array of pointers to the temporary Arg objects.

/***** The useful part: the matching interface *****/

// Matches "text" against "re". If pointer arguments are

// supplied, copies matched sub-patterns into them.

//

// You can pass in a "const char*" or a "std::string" for "text".

// You can pass in a "const char*" or a "std::string" or a "RE2" for "re".

//

// The provided pointer arguments can be pointers to any scalar numeric

// type, or one of:

// std::string (matched piece is copied to string)

// StringPiece (StringPiece is mutated to point to matched piece)

// T (where "bool T::ParseFrom(const char*, size_t)" exists)

// (void*)NULL (the corresponding matched sub-pattern is not copied)

//

// Returns true iff all of the following conditions are satisfied:

// a. "text" matches "re" fully - from the beginning to the end of "text".

// b. The number of matched sub-patterns is >= number of supplied pointers.

// c. The "i"th argument has a suitable type for holding the

// string captured as the "i"th sub-pattern. If you pass in

// NULL for the "i"th argument, or pass fewer arguments than

// number of sub-patterns, the "i"th captured sub-pattern is

// ignored.

//

// CAVEAT: An optional sub-pattern that does not exist in the

// matched string is assigned the empty string. Therefore, the

// following will return false (because the empty string is not a

// valid number):

// int number;

// RE2::FullMatch("abc", "[a-z]+(\\d+)?", &number);

template <typename... A>

static bool FullMatch(const StringPiece& text, const RE2& re, A&&... a) {

return Apply(FullMatchN, text, re, Arg(std::forward<A>(a))...);

}

// Like FullMatch(), except that "re" is allowed to match a substring

// of "text".

//

// Returns true iff all of the following conditions are satisfied:

// a. "text" matches "re" partially - for some substring of "text".

// b. The number of matched sub-patterns is >= number of supplied pointers.

// c. The "i"th argument has a suitable type for holding the

// string captured as the "i"th sub-pattern. If you pass in

// NULL for the "i"th argument, or pass fewer arguments than

// number of sub-patterns, the "i"th captured sub-pattern is

// ignored.

template <typename... A>

static bool PartialMatch(const StringPiece& text, const RE2& re, A&&... a) {

return Apply(PartialMatchN, text, re, Arg(std::forward<A>(a))...);

}

// Like FullMatch() and PartialMatch(), except that "re" has to match

// a prefix of the text, and "input" is advanced past the matched

// text. Note: "input" is modified iff this routine returns true

// and "re" matched a non-empty substring of "input".

//

// Returns true iff all of the following conditions are satisfied:

// a. "input" matches "re" partially - for some prefix of "input".

// b. The number of matched sub-patterns is >= number of supplied pointers.

// c. The "i"th argument has a suitable type for holding the

// string captured as the "i"th sub-pattern. If you pass in

// NULL for the "i"th argument, or pass fewer arguments than

// number of sub-patterns, the "i"th captured sub-pattern is

// ignored.

template <typename... A>

static bool Consume(StringPiece* input, const RE2& re, A&&... a) {

return Apply(ConsumeN, input, re, Arg(std::forward<A>(a))...);

}

// Like Consume(), but does not anchor the match at the beginning of

// the text. That is, "re" need not start its match at the beginning

// of "input". For example, "FindAndConsume(s, "(\\w+)", &word)" finds

// the next word in "s" and stores it in "word".

//

// Returns true iff all of the following conditions are satisfied:

// a. "input" matches "re" partially - for some substring of "input".

// b. The number of matched sub-patterns is >= number of supplied pointers.

// c. The "i"th argument has a suitable type for holding the

// string captured as the "i"th sub-pattern. If you pass in

// NULL for the "i"th argument, or pass fewer arguments than

// number of sub-patterns, the "i"th captured sub-pattern is

// ignored.

template <typename... A>

static bool FindAndConsume(StringPiece* input, const RE2& re, A&&... a) {

return Apply(FindAndConsumeN, input, re, Arg(std::forward<A>(a))...);

}

#endif

// Replace the first match of "re" in "str" with "rewrite".

// Within "rewrite", backslash-escaped digits (\1 to \9) can be

// used to insert text matching corresponding parenthesized group

// from the pattern. \0 in "rewrite" refers to the entire matching

// text. E.g.,

//

// std::string s = "yabba dabba doo";

// CHECK(RE2::Replace(&s, "b+", "d"));

//

// will leave "s" containing "yada dabba doo"

//

// Returns true if the pattern matches and a replacement occurs,

// false otherwise.

static bool Replace(std::string* str,

const RE2& re,

const StringPiece& rewrite);

// Like Replace(), except replaces successive non-overlapping occurrences

// of the pattern in the string with the rewrite. E.g.

//

// std::string s = "yabba dabba doo";

// CHECK(RE2::GlobalReplace(&s, "b+", "d"));

//

// will leave "s" containing "yada dada doo"

// Replacements are not subject to re-matching.

//

// Because GlobalReplace only replaces non-overlapping matches,

// replacing "ana" within "banana" makes only one replacement, not two.

//

// Returns the number of replacements made.

static int GlobalReplace(std::string* str,

const RE2& re,

const StringPiece& rewrite);

// Like Replace, except that if the pattern matches, "rewrite"

// is copied into "out" with substitutions. The non-matching

// portions of "text" are ignored.

//

// Returns true iff a match occurred and the extraction happened

// successfully; if no match occurs, the string is left unaffected.

//

// REQUIRES: "text" must not alias any part of "*out".

static bool Extract(const StringPiece& text,

const RE2& re,

const StringPiece& rewrite,

std::string* out);

// Escapes all potentially meaningful regexp characters in

// 'unquoted'. The returned string, used as a regular expression,

// will match exactly the original string. For example,

// 1.5-2.0?

// may become:

// 1\.5\-2\.0\?

static std::string QuoteMeta(const StringPiece& unquoted);

// Computes range for any strings matching regexp. The min and max can in

// some cases be arbitrarily precise, so the caller gets to specify the

// maximum desired length of string returned.

//

// Assuming PossibleMatchRange(&min, &max, N) returns successfully, any

// string s that is an anchored match for this regexp satisfies

// min <= s && s <= max.

//

// Note that PossibleMatchRange() will only consider the first copy of an

// infinitely repeated element (i.e., any regexp element followed by a '*' or

// '+' operator). Regexps with "{N}" constructions are not affected, as those

// do not compile down to infinite repetitions.

//

// Returns true on success, false on error.

bool PossibleMatchRange(std::string* min, std::string* max,

int maxlen) const;

// Generic matching interface

// Type of match.

enum Anchor {

UNANCHORED, // No anchoring

ANCHOR_START, // Anchor at start only

ANCHOR_BOTH // Anchor at start and end

};

// Return the number of capturing subpatterns, or -1 if the

// regexp wasn't valid on construction. The overall match ($0)

// does not count: if the regexp is "(a)(b)", returns 2.

int NumberOfCapturingGroups() const { return num_captures_; }

// Return a map from names to capturing indices.

// The map records the index of the leftmost group

// with the given name.

// Only valid until the re is deleted.

const std::map<std::string, int>& NamedCapturingGroups() const;

// Return a map from capturing indices to names.

// The map has no entries for unnamed groups.

// Only valid until the re is deleted.

const std::map<int, std::string>& CapturingGroupNames() const;

// General matching routine.

// Match against text starting at offset startpos

// and stopping the search at offset endpos.

// Returns true if match found, false if not.

// On a successful match, fills in submatch[] (up to nsubmatch entries)

// with information about submatches.

// I.e. matching RE2("(foo)|(bar)baz") on "barbazbla" will return true, with

// submatch[0] = "barbaz", submatch[1].data() = NULL, submatch[2] = "bar",

// submatch[3].data() = NULL, ..., up to submatch[nsubmatch-1].data() = NULL.

// Caveat: submatch[] may be clobbered even on match failure.

//

// Don't ask for more match information than you will use:

// runs much faster with nsubmatch == 1 than nsubmatch > 1, and

// runs even faster if nsubmatch == 0.

// Doesn't make sense to use nsubmatch > 1 + NumberOfCapturingGroups(),

// but will be handled correctly.

//

// Passing text == StringPiece(NULL, 0) will be handled like any other

// empty string, but note that on return, it will not be possible to tell

// whether submatch i matched the empty string or did not match:

// either way, submatch[i].data() == NULL.

bool Match(const StringPiece& text,

size_t startpos,

size_t endpos,

Anchor re_anchor,

StringPiece* submatch,

int nsubmatch) const;

// Check that the given rewrite string is suitable for use with this

// regular expression. It checks that:

// * The regular expression has enough parenthesized subexpressions

// to satisfy all of the \N tokens in rewrite

// * The rewrite string doesn't have any syntax errors. E.g.,

// '\' followed by anything other than a digit or '\'.

// A true return value guarantees that Replace() and Extract() won't

// fail because of a bad rewrite string.

bool CheckRewriteString(const StringPiece& rewrite,

std::string* error) const;

// Returns the maximum submatch needed for the rewrite to be done by

// Replace(). E.g. if rewrite == "foo \\2,\\1", returns 2.

static int MaxSubmatch(const StringPiece& rewrite);

// Append the "rewrite" string, with backslash subsitutions from "vec",

// to string "out".

// Returns true on success. This method can fail because of a malformed

// rewrite string. CheckRewriteString guarantees that the rewrite will

// be sucessful.

bool Rewrite(std::string* out,

const StringPiece& rewrite,

const StringPiece* vec,

int veclen) const;

// Constructor options

class Options {

public:

// The options are (defaults in parentheses):

//

// utf8 (true) text and pattern are UTF-8; otherwise Latin-1

// posix_syntax (false) restrict regexps to POSIX egrep syntax

// longest_match (false) search for longest match, not first match

// log_errors (true) log syntax and execution errors to ERROR

// max_mem (see below) approx. max memory footprint of RE2

// literal (false) interpret string as literal, not regexp

// never_nl (false) never match \n, even if it is in regexp

// dot_nl (false) dot matches everything including new line

// never_capture (false) parse all parens as non-capturing

// case_sensitive (true) match is case-sensitive (regexp can override

// with (?i) unless in posix_syntax mode)

//

// The following options are only consulted when posix_syntax == true.

// When posix_syntax == false, these features are always enabled and

// cannot be turned off; to perform multi-line matching in that case,

// begin the regexp with (?m).

// perl_classes (false) allow Perl's \d \s \w \D \S \W

// word_boundary (false) allow Perl's \b \B (word boundary and not)

// one_line (false) ^ and $ only match beginning and end of text

//

// The max_mem option controls how much memory can be used

// to hold the compiled form of the regexp (the Prog) and

// its cached DFA graphs. Code Search placed limits on the number

// of Prog instructions and DFA states: 10,000 for both.

// In RE2, those limits would translate to about 240 KB per Prog

// and perhaps 2.5 MB per DFA (DFA state sizes vary by regexp; RE2 does a

// better job of keeping them small than Code Search did).

// Each RE2 has two Progs (one forward, one reverse), and each Prog

// can have two DFAs (one first match, one longest match).

// That makes 4 DFAs:

//

// forward, first-match - used for UNANCHORED or ANCHOR_START searches

// if opt.longest_match() == false

// forward, longest-match - used for all ANCHOR_BOTH searches,

// and the other two kinds if

// opt.longest_match() == true

// reverse, first-match - never used

// reverse, longest-match - used as second phase for unanchored searches

//

// The RE2 memory budget is statically divided between the two

// Progs and then the DFAs: two thirds to the forward Prog

// and one third to the reverse Prog. The forward Prog gives half

// of what it has left over to each of its DFAs. The reverse Prog

// gives it all to its longest-match DFA.

//

// Once a DFA fills its budget, it flushes its cache and starts over.

// If this happens too often, RE2 falls back on the NFA implementation.

// For now, make the default budget something close to Code Search.

static const int kDefaultMaxMem = 8<<20;

enum Encoding {

EncodingUTF8 = 1,

EncodingLatin1

};

Options() :

encoding_(EncodingUTF8),

posix_syntax_(false),

longest_match_(false),

log_errors_(true),

max_mem_(kDefaultMaxMem),

literal_(false),

never_nl_(false),

dot_nl_(false),

never_capture_(false),

case_sensitive_(true),

perl_classes_(false),

word_boundary_(false),

one_line_(false) {

}

/*implicit*/ Options(CannedOptions);

Encoding encoding() const { return encoding_; }

void set_encoding(Encoding encoding) { encoding_ = encoding; }

bool posix_syntax() const { return posix_syntax_; }

void set_posix_syntax(bool b) { posix_syntax_ = b; }

bool longest_match() const { return longest_match_; }

void set_longest_match(bool b) { longest_match_ = b; }

bool log_errors() const { return log_errors_; }

void set_log_errors(bool b) { log_errors_ = b; }

int64_t max_mem() const { return max_mem_; }

void set_max_mem(int64_t m) { max_mem_ = m; }

bool literal() const { return literal_; }

void set_literal(bool b) { literal_ = b; }

bool never_nl() const { return never_nl_; }

void set_never_nl(bool b) { never_nl_ = b; }

bool dot_nl() const { return dot_nl_; }

void set_dot_nl(bool b) { dot_nl_ = b; }

bool never_capture() const { return never_capture_; }

void set_never_capture(bool b) { never_capture_ = b; }

bool case_sensitive() const { return case_sensitive_; }

void set_case_sensitive(bool b) { case_sensitive_ = b; }

bool perl_classes() const { return perl_classes_; }

void set_perl_classes(bool b) { perl_classes_ = b; }

bool word_boundary() const { return word_boundary_; }

void set_word_boundary(bool b) { word_boundary_ = b; }

bool one_line() const { return one_line_; }

void set_one_line(bool b) { one_line_ = b; }

void Copy(const Options& src) {

*this = src;

}

int ParseFlags() const;

private:

Encoding encoding_;

bool posix_syntax_;

bool longest_match_;

bool log_errors_;

int64_t max_mem_;

bool literal_;

bool never_nl_;

bool dot_nl_;

bool never_capture_;

bool case_sensitive_;

bool perl_classes_;

bool word_boundary_;

bool one_line_;

};

// Returns the options set in the constructor.

const Options& options() const { return options_; }

// Argument converters; see below.

template <typename T>

static Arg CRadix(T* ptr);

template <typename T>

static Arg Hex(T* ptr);

template <typename T>

static Arg Octal(T* ptr);

private:

void Init(const StringPiece& pattern, const Options& options);

bool DoMatch(const StringPiece& text,

Anchor re_anchor,

size_t* consumed,

const Arg* const args[],

int n) const;

re2::Prog* ReverseProg() const;

std::string pattern_; // string regular expression

Options options_; // option flags

re2::Regexp* entire_regexp_; // parsed regular expression

const std::string* error_; // error indicator (or points to empty string)

ErrorCode error_code_; // error code

std::string error_arg_; // fragment of regexp showing error

std::string prefix_; // required prefix (before suffix_regexp_)

bool prefix_foldcase_; // prefix_ is ASCII case-insensitive

re2::Regexp* suffix_regexp_; // parsed regular expression, prefix_ removed

re2::Prog* prog_; // compiled program for regexp

int num_captures_; // number of capturing groups

bool is_one_pass_; // can use prog_->SearchOnePass?

// Reverse Prog for DFA execution only

mutable re2::Prog* rprog_;

// Map from capture names to indices

mutable const std::map<std::string, int>* named_groups_;

// Map from capture indices to names

mutable const std::map<int, std::string>* group_names_;

mutable std::once_flag rprog_once_;

mutable std::once_flag named_groups_once_;

mutable std::once_flag group_names_once_;

RE2(const RE2&) = delete;

RE2& operator=(const RE2&) = delete;

};

/***** Implementation details *****/

namespace re2_internal {

// Types for which the 3-ary Parse() function template has specializations.

template <typename T> struct Parse3ary : public std::false_type {};

template <> struct Parse3ary<void> : public std::true_type {};

template <> struct Parse3ary<std::string> : public std::true_type {};

template <> struct Parse3ary<StringPiece> : public std::true_type {};

template <> struct Parse3ary<char> : public std::true_type {};

template <> struct Parse3ary<signed char> : public std::true_type {};

template <> struct Parse3ary<unsigned char> : public std::true_type {};

template <> struct Parse3ary<float> : public std::true_type {};

template <> struct Parse3ary<double> : public std::true_type {};

template <typename T>

bool Parse(const char* str, size_t n, T* dest);

// Types for which the 4-ary Parse() function template has specializations.

template <typename T> struct Parse4ary : public std::false_type {};

template <> struct Parse4ary<long> : public std::true_type {};

template <> struct Parse4ary<unsigned long> : public std::true_type {};

template <> struct Parse4ary<short> : public std::true_type {};

template <> struct Parse4ary<unsigned short> : public std::true_type {};

template <> struct Parse4ary<int> : public std::true_type {};

template <> struct Parse4ary<unsigned int> : public std::true_type {};

template <> struct Parse4ary<long long> : public std::true_type {};

template <> struct Parse4ary<unsigned long long> : public std::true_type {};

template <typename T>

bool Parse(const char* str, size_t n, T* dest, int radix);

} // namespace re2_internal

class RE2::Arg {

private:

template <typename T>

using CanParse3ary = typename std::enable_if<

re2_internal::Parse3ary<T>::value,

int>::type;

template <typename T>

using CanParse4ary = typename std::enable_if<

re2_internal::Parse4ary<T>::value,

int>::type;

#if !defined(_MSC_VER)

template <typename T>

using CanParseFrom = typename std::enable_if<

std::is_member_function_pointer<

decltype(static_cast<bool (T::*)(const char*, size_t)>(

&T::ParseFrom))>::value,

int>::type;

#endif

public:

Arg() : Arg(nullptr) {}

Arg(std::nullptr_t ptr) : arg_(ptr), parser_(DoNothing) {}

template <typename T, CanParse3ary<T> = 0>

Arg(T* ptr) : arg_(ptr), parser_(DoParse3ary<T>) {}

template <typename T, CanParse4ary<T> = 0>

Arg(T* ptr) : arg_(ptr), parser_(DoParse4ary<T>) {}

#if !defined(_MSC_VER)

template <typename T, CanParseFrom<T> = 0>

Arg(T* ptr) : arg_(ptr), parser_(DoParseFrom<T>) {}

#endif

typedef bool (*Parser)(const char* str, size_t n, void* dest);

template <typename T>

Arg(T* ptr, Parser parser) : arg_(ptr), parser_(parser) {}

bool Parse(const char* str, size_t n) const {

return (*parser_)(str, n, arg_);

}

private:

static bool DoNothing(const char* /*str*/, size_t /*n*/, void* /*dest*/) {

return true;

}

template <typename T>

static bool DoParse3ary(const char* str, size_t n, void* dest) {

return re2_internal::Parse(str, n, reinterpret_cast<T*>(dest));

}

template <typename T>

static bool DoParse4ary(const char* str, size_t n, void* dest) {

return re2_internal::Parse(str, n, reinterpret_cast<T*>(dest), 10);

}

#if !defined(_MSC_VER)

template <typename T>

static bool DoParseFrom(const char* str, size_t n, void* dest) {

if (dest == NULL) return true;

return reinterpret_cast<T*>(dest)->ParseFrom(str, n);

}

#endif

void* arg_;

Parser parser_;

};

template <typename T>

inline RE2::Arg RE2::CRadix(T* ptr) {

return RE2::Arg(ptr, [](const char* str, size_t n, void* dest) -> bool {

return re2_internal::Parse(str, n, reinterpret_cast<T*>(dest), 0);

});

}

template <typename T>

inline RE2::Arg RE2::Hex(T* ptr) {

return RE2::Arg(ptr, [](const char* str, size_t n, void* dest) -> bool {

return re2_internal::Parse(str, n, reinterpret_cast<T*>(dest), 16);

});

}

template <typename T>

inline RE2::Arg RE2::Octal(T* ptr) {

return RE2::Arg(ptr, [](const char* str, size_t n, void* dest) -> bool {

return re2_internal::Parse(str, n, reinterpret_cast<T*>(dest), 8);

});

}

#ifndef SWIG

// Silence warnings about missing initializers for members of LazyRE2.

#if !defined(__clang__) && defined(__GNUC__) && __GNUC__ >= 6

#pragma GCC diagnostic ignored "-Wmissing-field-initializers"

#endif

// Helper for writing global or static RE2s safely.

// Write

// static LazyRE2 re = {".*"};

// and then use *re instead of writing

// static RE2 re(".*");

// The former is more careful about multithreaded

// situations than the latter.

//

// N.B. This class never deletes the RE2 object that

// it constructs: that's a feature, so that it can be used

// for global and function static variables.

class LazyRE2 {

private:

struct NoArg {};

public:

typedef RE2 element_type; // support std::pointer_traits

// Constructor omitted to preserve braced initialization in C++98.

// Pretend to be a pointer to Type (never NULL due to on-demand creation):

RE2& operator*() const { return *get(); }

RE2* operator->() const { return get(); }

// Named accessor/initializer:

RE2* get() const {

std::call_once(once_, &LazyRE2::Init, this);

return ptr_;

}

// All data fields must be public to support {"foo"} initialization.

const char* pattern_;

RE2::CannedOptions options_;

NoArg barrier_against_excess_initializers_;

mutable RE2* ptr_;

mutable std::once_flag once_;

private:

static void Init(const LazyRE2* lazy_re2) {

lazy_re2->ptr_ = new RE2(lazy_re2->pattern_, lazy_re2->options_);

}

void operator=(const LazyRE2&); // disallowed

};

#endif

namespace hooks {

// Most platforms support thread_local. Older versions of iOS don't support

// thread_local, but for the sake of brevity, we lump together all versions

// of Apple platforms that aren't macOS. If an iOS application really needs

// the context pointee someday, we can get more specific then...

#define RE2_HAVE_THREAD_LOCAL

#if defined(__APPLE__) && !TARGET_OS_OSX

#undef RE2_HAVE_THREAD_LOCAL

#endif

// A hook must not make any assumptions regarding the lifetime of the context

// pointee beyond the current invocation of the hook. Pointers and references

// obtained via the context pointee should be considered invalidated when the

// hook returns. Hence, any data about the context pointee (e.g. its pattern)

// would have to be copied in order for it to be kept for an indefinite time.

//

// A hook must not use RE2 for matching. Control flow reentering RE2::Match()

// could result in infinite mutual recursion. To discourage that possibility,

// RE2 will not maintain the context pointer correctly when used in that way.

#ifdef RE2_HAVE_THREAD_LOCAL

extern thread_local const RE2* context;

#endif

struct DFAStateCacheReset {

int64_t state_budget;

size_t state_cache_size;

};

struct DFASearchFailure {

// Nothing yet...

};

#define DECLARE_HOOK(type) \

using type##Callback = void(const type&); \

void Set##type##Hook(type##Callback* cb); \

type##Callback* Get##type##Hook();