//
// RegularExpression.h
//
// Library: Foundation
// Package: RegExp
// Module: RegularExpression
//
// Definitions of class RegularExpression.
//
// A wrapper class for Philip Hazel's PCRE - Perl Compatible Regular Expressions
// library (http://www.pcre.org).
//
// Copyright (c) 2004-2006, Applied Informatics Software Engineering GmbH.
// and Contributors.
//
// SPDX-License-Identifier: BSL-1.0
//
#ifndef Foundation_RegularExpression_INCLUDED
#define Foundation_RegularExpression_INCLUDED
#include "Poco/Foundation.h"
#include <vector>
#include <map>
namespace Poco {
class Foundation_API RegularExpression
/// A class for working with regular expressions.
/// Implemented using PCRE2, the Perl Compatible
/// Regular Expressions library by Philip Hazel
/// (see http://www.pcre.org).
{
public:
enum Options
/// Some of the following options can only be passed to the constructor;
/// some can be passed only to matching functions, and some can be used
/// everywhere.
///
/// * Options marked [ctor] can be passed to the constructor.
/// * Options marked [match] can be passed to match, extract, split and subst.
/// * Options marked [subst] can be passed to subst.
///
/// See the PCRE documentation for more information.
{
RE_CASELESS = 0x00000001, /// case insensitive matching (/i) [ctor]
RE_MULTILINE = 0x00000002, /// enable multi-line mode; affects ^ and $ (/m) [ctor]
RE_DOTALL = 0x00000004, /// dot matches all characters, including newline (/s) [ctor]
RE_EXTENDED = 0x00000008, /// totally ignore whitespace (/x) [ctor]
RE_ANCHORED = 0x00000010, /// treat pattern as if it starts with a ^ [ctor, match]
RE_DOLLAR_ENDONLY = 0x00000020, /// dollar matches end-of-string only, not last newline in string [ctor]
RE_EXTRA = 0x00000040, /// enable optional PCRE functionality [ctor]
RE_NOTBOL = 0x00000080, /// circumflex does not match beginning of string [match]
RE_NOTEOL = 0x00000100, /// $ does not match end of string [match]
RE_UNGREEDY = 0x00000200, /// make quantifiers ungreedy [ctor]
RE_NOTEMPTY = 0x00000400, /// empty string never matches [match]
RE_UTF8 = 0x00000800, /// assume pattern and subject is UTF-8 encoded [ctor]
RE_NO_AUTO_CAPTURE = 0x00001000, /// disable numbered capturing parentheses [ctor, match]
RE_NO_UTF8_CHECK = 0x00002000, /// do not check validity of UTF-8 code sequences [match]
RE_FIRSTLINE = 0x00040000, /// an unanchored pattern is required to match
/// before or at the first newline in the subject string,
/// though the matched text may continue over the newline [ctor]
RE_DUPNAMES = 0x00080000, /// names used to identify capturing subpatterns need not be unique [ctor]
RE_NEWLINE_CR = 0x00100000, /// assume newline is CR ('\r'), the default [ctor]
RE_NEWLINE_LF = 0x00200000, /// assume newline is LF ('\n') [ctor]
RE_NEWLINE_CRLF = 0x00300000, /// assume newline is CRLF ("\r\n") [ctor]
RE_NEWLINE_ANY = 0x00400000, /// assume newline is any valid Unicode newline character [ctor]
RE_NEWLINE_ANYCRLF = 0x00500000, /// assume newline is any of CR, LF, CRLF [ctor]
RE_GLOBAL = 0x10000000, /// replace all occurences (/g) [subst]
RE_NO_VARS = 0x20000000 /// treat dollar in replacement string as ordinary character [subst]
};
struct Match
{
std::string::size_type offset; /// zero based offset (std::string::npos if subexpr does not match)
std::string::size_type length; /// length of substring
std::string name; /// name of group
};
using MatchVec = std::vector<Match>;
using GroupMap = std::map<int, std::string>;
RegularExpression(const std::string& pattern, int options = 0, bool study = true);
/// Creates a regular expression and parses the given pattern.
/// Note: the study argument is only provided for backwards compatibility
/// and is ignored since POCO release 1.12, which uses PCRE2.
/// For a description of the options, please see the PCRE documentation.
/// Throws a RegularExpressionException if the patter cannot be compiled.
~RegularExpression();
/// Destroys the regular expression.
int match(const std::string& subject, Match& mtch, int options = 0) const;
/// Matches the given subject string against the pattern. Returns the position
/// of the first captured substring in mtch.
/// If no part of the subject matches the pattern, mtch.offset is std::string::npos and
/// mtch.length is 0.
/// Throws a RegularExpressionException in case of an error.
/// Returns the number of matches.
int match(const std::string& subject, std::string::size_type offset, Match& mtch, int options = 0) const;
/// Matches the given subject string, starting at offset, against the pattern.
/// Returns the position of the captured substring in mtch.
/// If no part of the subject matches the pattern, mtch.offset is std::string::npos and
/// mtch.length is 0.
/// Throws a RegularExpressionException in case of an error.
/// Returns the number of matches.
int match(const std::string& subject, std::string::size_type offset, MatchVec& matches, int options = 0) const;
/// Matches the given subject string against the pattern.
/// The first entry in matches contains the position of the captured substring.
/// The following entries identify matching subpatterns. See the PCRE documentation
/// for a more detailed explanation.
/// If no part of the subject matches the pattern, matches is empty.
/// Throws a RegularExpressionException in case of an error.
/// Returns the number of matches.
bool match(const std::string& subject, std::string::size_type offset = 0) const;
/// Returns true if and only if the subject matches the regular expression.
///
/// Internally, this method sets the RE_ANCHORED and RE_NOTEMPTY options for
/// matching, which means that the empty string will never match and
/// the pattern is treated as if it starts with a ^.
bool match(const std::string& subject, std::string::size_type offset, int options) const;
/// Returns true if and only if the subject matches the regular expression.
bool operator == (const std::string& subject) const;
/// Returns true if and only if the subject matches the regular expression.
///
/// Internally, this method sets the RE_ANCHORED and RE_NOTEMPTY options for
/// matching, which means that the empty string will never match and
/// the pattern is treated as if it starts with a ^.
bool operator != (const std::string& subject) const;
/// Returns true if and only if the subject does not match the regular expression.
///
/// Internally, this method sets the RE_ANCHORED and RE_NOTEMPTY options for
/// matching, which means that the empty string will never match and
/// the pattern is treated as if it starts with a ^.
int extract(const std::string& subject, std::string& str, int options = 0) const;
/// Matches the given subject string against the pattern.
/// Returns the captured string.
/// Throws a RegularExpressionException in case of an error.
/// Returns the number of matches.
int extract(const std::string& subject, std::string::size_type offset, std::string& str, int options = 0) const;
/// Matches the given subject string, starting at offset, against the pattern.
/// Returns the captured string.
/// Throws a RegularExpressionException in case of an error.
/// Returns the number of matches.
int split(const std::string& subject, std::vector<std::string>& strings, int options = 0) const;
/// Matches the given subject string against the pattern.
/// The first entry in captured is the captured substring.
/// The following entries contain substrings matching subpatterns. See the PCRE documentation
/// for a more detailed explanation.
/// If no part of the subject matches the pattern, captured is empty.
/// Throws a RegularExpressionException in case of an error.
/// Returns the number of matches.
int split(const std::string& subject, std::string::size_type offset, std::vector<std::string>& strings, int options = 0) const;
/// Matches the given subject string against the pattern.
/// The first entry in captured is the captured substring.
/// The following entries contain substrings matching subpatterns. See the PCRE documentation
/// for a more detailed explanation.
/// If no part of the subject matches the pattern, captured is empty.
/// Throws a RegularExpressionException in case of an error.
/// Returns the number of matches.
int subst(std::string& subject, const std::string& replacement, int options = 0) const;
/// Substitute in subject all matches of the pattern with replacement.
/// If RE_GLOBAL is specified as option, all matches are replaced. Otherwise,
/// only the first match is replaced.
/// Occurrences of $<n> (for example, $1, $2, ...) in replacement are replaced
/// with the corresponding captured string. $0 is the original subject string.
/// Returns the number of replaced occurrences.
int subst(std::string& subject, std::string::size_type offset, const std::string& replacement, int options = 0) const;
/// Substitute in subject all matches of the pattern with replacement,
/// starting at offset.
/// If RE_GLOBAL is specified as option, all matches are replaced. Otherwise,
/// only the first match is replaced.
/// Unless RE_NO_VARS is specified, occurrences of $<n> (for example, $0, $1, $2, ... $9)
/// in replacement are replaced with the corresponding captured string.
/// $0 is the captured substring. $1 ... $n are the substrings matching the subpatterns.
/// Returns the number of replaced occurrences.
static bool match(const std::string& subject, const std::string& pattern, int options = 0);
/// Matches the given subject string against the regular expression given in pattern,
/// using the given options.
protected:
std::string::size_type substOne(std::string& subject, std::string::size_type offset, const std::string& replacement, int options) const;
static int compileOptions(int options);
static int matchOptions(int options);
private:
// Note: to avoid a dependency on the pcre2.h header the following are
// declared as void* and casted to the correct type in the implementation file.
void* _pcre; // Actual type is pcre2_code_8*
GroupMap _groups;
RegularExpression();
RegularExpression(const RegularExpression&);
RegularExpression& operator = (const RegularExpression&);
};
//
// inlines
//
inline int RegularExpression::match(const std::string& subject, Match& mtch, int options) const
{
return match(subject, 0, mtch, options);
}
inline int RegularExpression::split(const std::string& subject, std::vector<std::string>& strings, int options) const
{
return split(subject, 0, strings, options);
}
inline int RegularExpression::subst(std::string& subject, const std::string& replacement, int options) const
{
return subst(subject, 0, replacement, options);
}
inline bool RegularExpression::operator == (const std::string& subject) const
{
return match(subject);
}
inline bool RegularExpression::operator != (const std::string& subject) const
{
return !match(subject);
}
} // namespace Poco
#endif // Foundation_RegularExpression_INCLUDED