/**************************************************************************** ** $Id$ ** ** Implementation of QRegExp class ** ** Created : 950126 ** ** Copyright (C) 1992-2000 Trolltech AS. All rights reserved. ** ** This file is part of the tools module of the Qt GUI Toolkit. ** ** This file may be distributed under the terms of the Q Public License ** as defined by Trolltech AS of Norway and appearing in the file ** LICENSE.QPL included in the packaging of this file. ** ** This file may be distributed and/or modified under the terms of the ** GNU General Public License version 2 as published by the Free Software ** Foundation and appearing in the file LICENSE.GPL included in the ** packaging of this file. ** ** Licensees holding valid Qt Enterprise Edition or Qt Professional Edition ** licenses may use this file in accordance with the Qt Commercial License ** Agreement provided with the Software. ** ** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE ** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. ** ** See http://www.trolltech.com/pricing.html or email sales@trolltech.com for ** information about Qt Commercial License Agreements. ** See http://www.trolltech.com/qpl/ for QPL licensing information. ** See http://www.trolltech.com/gpl/ for GPL licensing information. ** ** Contact info@trolltech.com if any conditions of this licensing are ** not clear to you. ** **********************************************************************/ #if QT_VERSION >=300 #error QRegExp3 is now in QT 3 use QRegExp instead #endif #include "qarray.h" #include "qbitarray.h" #include "qcache.h" #include "qintdict.h" #include "qmap.h" #if QT_VERSION < 300 #include "./qregexp3.h" #else #include "qregexp.h" #endif #include "qstring.h" #include "qtl.h" #include "qvector.h" #include /* WARNING! Be sure to read qregexp.tex before modifying this file. */ /*! \class QRegExp3 qregexp.h \brief The QRegExp class provides pattern matching using regular expressions. \ingroup tools \ingroup misc \ingroup shared Regular expressions, "regexps", provide a way to find patterns within text. This is useful in many contexts, for example:
  1. \e Validation. A regexp can be used to check whether a piece of text meets some criteria, e.g. is an integer or contains no whitespace.
  2. \e Searching. Regexps provide a much more powerful means of searching text than simple string matching does. For example we can create a regexp which says "find one of the words 'mail', 'letter' or 'correspondence' but not any of the words 'email', 'mailman' 'mailer', 'letterbox' etc."
  3. Search and Replace. A regexp can be used to replace a pattern with a piece of text, for example replace all occurrences of '&' with '\&' except where the '&' is already followed by 'amp;'.
  4. String Splitting. A regexp can be used to identify where a string should be split into its component fields, e.g. splitting tab delimited strings.
We present a very brief introduction to regexps, a description of Qt's regexp language, some code examples, and finally the function documentation. QRegExp is modelled on Perl's regexp engine and fully supports Unicode. QRegExp may also be used in the weaker 'wildcard' (globbing) mode which works in a similar way to command shells. A good text on regexps is Mastering Regular Expressions: Powerful Techniques for Perl and Other Tools by Jeffrey E. Friedl, ISBN 1565922573. Experienced regexp users may prefer to skip the introduction and go directly to the relevant information: Introduction Regexps are built up from expressions, quantifiers and assertions. The simplest form of expression is simply a character, e.g. x or 5. An expression can also be a set of characters. For example, [ABCD], will match an A or a B or a C or a D. As a shorthand we could write this as [A-D]. If we want to match any of the captital letters in the English alphabet we can write [A-Z]. A quantifier tells the regexp engine how many occurrences of the expression we want, e.g. x{1,1} means match an x which occurs at least once and at most once. We'll look at assertions and more complex expressions later. Note that regexps cannot be used to check for balanced brackets or tags (unless you know the maximum level of nesting). We'll start by writing a regexp to match integers in the range 0 to 99. We will require at least one digit so we will start with [0-9]{1,1} which means match a digit exactly once. This regexp alone will match integers in the range 0 to 9. To match one or two digits we can increase the maximum number of occurrences so the regexp becomes [0-9]{1,2} meaning match a digit at least once and at most twice. However, this regexp as it stands will not match correctly. This regexp will match one or two digits \e within a string. To ensure that we match against the whole string we must use the anchor assertions. We need ^ (caret) which when it is the first character in the regexp means that the regexp must match from the beginning of the string. And we also need $ (dollar) which when it is the last character in the regexp means that the regexp must match until the end of the string. So now our regexp is ^[0-9]{1,2}$. Note that assertions do not match any characters. If you've seen regexps elsewhere they may have looked different from the one above. This is because some sets of characters and some quantifiers are so common that they have special symbols to represent them. [0-9] can be replaced with the symbol \d. The quantifier to match exactly one occurrence, {1,1}, can be replaced with the expression itself. This means that x{1,1} is exactly the same as x alone. So our 0 to 99 matcher could be written: ^\d{1,2}$, although most people would write it ^\d\d?$. The ? is the same as the quantifier {0,1}, i.e. a minimum of no occurrences a maximum of one occurrence. This is used to make an expression optional. The regexp ^\d\d?$ means "from the beginning of the string match one digit followed by zero or one digits and then the end of the string". Our second example is matching the words 'mail', 'letter' or 'correspondence' but without matching 'email', 'mailman', 'mailer', 'letterbox' etc. We'll start by just matching 'mail'. In full the regexp is, m{1,1}a{1,1}i{1,1}l{1,1}, but since an expression itself is automatically quantified by {1,1} we can simply write this as mail; an 'm' followed by an 'a' followed by an 'i' followed by an 'l'. The symbol '|' (bar) is used for \e alternation, so our regexp now becomes mail|letter|correspondence which means match 'mail' \e or 'letter' \e or 'correspondence'. Whilst this regexp will find the words we want it will also find words we don't want such as 'email'. We will start by putting our regexp in parenthesis (mail|letter|correspondence). Parenthesis have two effects, firstly they group expressions together and secondly they identify parts of the regexp that we wish to capture. Our regexp still matches any of the three words but now they are grouped together as a unit. This is useful for building up more complex regexps. It is also useful because it allows us to examine which of the words actually matched. We need to use another assertion, this time \b "word boundary": \b(mail|letter|correspondence)\b. This regexp means "match a word boundary followed by the expression in parenthesis followed by another word boundary". The \b assertion matches at a \e position in the regexp not a \e character in the regexp. A word boundary is any non-word character such as a space a newline or the beginning or end of the string. For our third example we want to replace ampersands with the HTML entity '\&'. The regexp to match is simple: \&, i.e. match one ampersand. Unfortunately this will mess up our text if some of the ampersands have already been turned into HTML entities. So what we really want to say is replace an ampersand providing it is not followed by 'amp;'. For this we need the negative lookahead assertion and our regexp becomes: \&(?!amp;). The negative lookahead assertion is introduced with '(?!' and finishes at the ')'. It means that the text it contains, 'amp;' in our example, must \e not follow the expression that preceeds it. Regexps provide a rich language that can be used in a variety of ways. For example suppose we want to count all the occurrences of 'Eric' and 'Eirik' in a string. Two valid regexps to match these are \\b(Eric|Eirik)\\b and \\bEi?ri[ck]\\b. We need the word boundary '\b' so we don't get 'Ericsson' etc. The second regexp actually matches more than we want, 'Eric', 'Erik', 'Eiric' and 'Eirik'. We will implement some the examples above in the code examples section. Characters and Abbreviations for Sets of Characters Note that the C++ compiler transforms backslashes in strings so to include a \\ in a regexp you will need to enter it twice, i.e. \\\\. Sets of Characters Square brackets are used to match any character in the set of characters contained within the square brackets. All the character set abbreviations described above can be used within square brackets. Apart from the character set abbreviations and the following two exceptions no characters have special meanings in square brackets. Using the predefined character set abbreviations is more portable than using character ranges across platforms and languages. For example, [0-9] matches a digit in Western alphabets but \d matches a digit in \e any alphabet. Note that in most regexp literature sets of characters are called "character classes". Quantifiers By default an expression is automatically quantified by {1,1}, i.e. it should occur exactly once. In the following list E stands for any expression. An expression is a character or an abbreviation for a set of characters or a set of characters in square brackets or any parenthesised expression. (MAXINT is implementation dependent but will not be smaller than 16384.) If we wish to apply a quantifier to more than just the preceeding character we can use parenthesis to group characters together in an expression. For example, tag+ matches a 't' followed by an 'a' followed by at least one 'g', whereas (tag)+ matches at least one occurrence of 'tag'. Note that quantifiers are "greedy", they will match as much text as they can. For example, 0+ will match as many zeros as it can from the first zero it finds, e.g. '2.0005'. Quantifiers can be made non-greedy, see setMinimal(). Capturing Text Parenthesis allow us to group elements together so that we can quantify and capture them. For example if we have the expression mail|letter|correspondence that matches a string we know that \e one of the words matched but not which one. Using parenthesis allows us to "capture" whatever is matched within their bounds, so if we used (mail|letter|correspondence) and matched this regexp against the string "I sent you some email" we can use the cap() or capturedTexts() functions to extract the matched characters, in this case 'mail'. We can use captured text within the regexp itself. To refer to the captured text we use \e backreferences which are indexed from 1 the same as for cap(). For example we could search for duplicate words in a string using \b(\w+)\W+\1\b which means match a word boundary followed by one or more word characters followed by one or more non-word characters followed by the same text as the first parenthesised expression followed by a word boundary. If we want to use parenthesis purely for grouping and not for capturing we use the non-capturing syntax, e.g. (?:green|blue). Non-capturing parenthesis begin '(?:' and end ')'. In this example we match either 'green' or 'blue' but we do not capture the match so we can only know whether or not we matched but not which color we actually found. Using non-capturing parenthesis is more efficient than using capturing parenthesis since the regexp engine has to do less book-keeping. Both capturing and non-capturing parenthesis may be nested. Assertions Assertions make some statement about the text at the point where they occur in the regexp but they do not match any characters. In the following list E stands for any expression. Wildcard Matching (globbing) Most command shells such as \e bash or \e cmd support "file globbing", the ability to identify a group of files by using wildcards. Wildcard matching is much simpler than full regexps and has only four features: For example if we are in wildcard mode and have strings which contain filenames we could identify HTML files with *.html. This will match zero or more characters followed by a dot followed by 'h', 't', 'm' and 'l'. Notes for Perl Users Most of the character class abbreviations supported by Perl are supported by QRegExp, see characters and abbreviations for sets of characters. QRegExp's quantifiers are the same as Perl's greedy quantifiers. Non-greedy matching cannot be applied to individual quantifiers, but can be applied to all the quantifiers in the pattern. For example, to match the Perl regex ro+?m requires: \code QRegExp rx( "ro+m" ); rx.setMinimal( TRUE ); \endcode The equivalent of Perl's /i option is setCaseSensitive(FALSE). Perl's /g option can be emulated using a loop. In QRegExp . matches any character, therefore all QRegExp regexps have the equivalent of Perl's /s option. QRegExp does not have an equivalent to Perl's /m option, but this can be emulated in various ways for example by splitting the input into lines or by looping with a regexp that searches for newlines. Because QRegExp is string oriented there are no \A, \Z or \z assertions. The \G assertion is not supported but can be emulated in a loop. Perl's $& is cap(0) or capturedTexts()[0]. There are no QRegExp equivalents for $`, $' or $+. $1, $2 etc correspond to cap(1) or capturedTexts()[1], cap(2) or capturedTexts()[2], etc. To substitute a pattern use QString::replace(). Perl's extended /x syntax is not supported, nor are regexp comments (?#comment) or directives, e.g. (?i). Both zero-width positive and zero-width negative lookahead assertions (?=pattern) and (?!pattern) are supported with the same syntax as Perl. Perl's lookbehind assertions, "independent" subexpressions and conditional expressions are not supported. Non-capturing parenthesis are also supported, with the same (?:pattern) syntax. See QStringList::split() and QStringList::join() for equivalents to Perl's split and join functions. Note: because C++ transforms \\'s they must be written \e twice in code, e.g. \\b must be written \\\\b. Code Examples \code QRegExp rx( "^\\d\\d?$" ); // Match integers 0 to 99 rx.search( "123" ); // Returns -1 (no match) rx.search( "-6" ); // Returns -1 (no match) rx.search( "6" ); // Returns 0 (matched as position 0) \endcode The third string matches '6'. This is a simple validation regexp for integers in the range 0 to 99. \code QRegExp rx( "^\\S+$" ); // Match strings which have no whitespace rx.search( "Hello world" ); // Returns -1 (no match) rx.search( "This_is-OK" ); // Returns 0 (matched at position 0) \endcode The second string matches 'This_is-OK'. We've used the character set abbreviation '\S' (non-whitespace) and the anchors to match strings which contain no whitespace. In the following example we match strings containing 'mail' or 'letter' or 'correspondence' but only match whole words i.e. not 'email' \code QRegExp rx( "\\b(mail|letter|correspondence)\\b" ); rx.search( "I sent you an email" ); // Returns -1 (no match) rx.search( "Please write the letter" ); // Returns 17 (matched at position 17) \endcode The second string matches "Please write the letter". The word 'letter' is also captured (because of the parenthesis). We can see what text we've captured like this: \code QString captured = rx.cap( 1 ); // captured contains "letter" \endcode This will capture the text from the first set of capturing parenthesis (counting capturing left parenthesis from left to right). The parenthesis are counted from 1 since cap( 0 ) is the whole matched regexp (equivalent to '&' in most regexp engines). \code QRegExp rx( "&(?!amp;)" ); // Match ampersands but not & QString line1 = "This & that"; line1.replace( rx, "&" ); // line1 == "This & that" QString line2 = "His & hers & theirs"; line2.replace( rx, "&" ); // line2 == "His & hers & theirs" \endcode Here we've passed the QRegExp to QString's replace() function to replace the matched text with new text. \code QString str = "One Eric another Eirik, and an Ericsson. How many Eiriks, Eric?"; QRegExp rx( "\\b(Eric|Eirik)\\b" ); // Match Eric or Eirik int pos = 0; // Where we are in the string int count = 0; // How many Eric and Eirik's we've counted while ( pos >= 0 ) { pos = rx.search( str, pos ); if ( pos >= 0 ) { pos++; // Move along in str count++; // Count our Eric or Eirik } } \endcode We've used the search() function to repeatedly match the regexp in the string. Note that instead of moving forward by one character at a time pos++ we could have written pos += rx.matchedLength() to skip over the already matched string. The count will equal 3, matching 'One Eric another Eirik, and an Ericsson. How many Eiriks, Eric?'; it doesn't match 'Ericsson' or 'Eiriks' because they are not bounded by non-word boundaries. One common use of regexps is to split lines of delimited data into their component fields. \code str = "Trolltech AS\twww.trolltech.com\tNorway"; QString company, web, country; rx.setPattern( "^([^\t]+)\t([^\t]+)\t([^\t]+)$" ); if ( rx.search( str ) != -1 ) { company = rx.cap( 1 ); web = rx.cap( 2 ); country = rx.cap( 3 ); } \endcode In this example our input lines have the format company name, web address and country. Unfortunately the regexp is rather long and not very versatile -- the code will break if we add any more fields. A simpler and better solution is to look for the separator, '\t' in this case, and take the surrounding text. The QStringList split() function can take a separator string or regexp as an argument and split a string accordingly. \code QStringList field = QStringList::split( "\t", str ); \endcode Here field[0] is the company, field[1] the web address and so on. To immitate the matching of a shell we can use wildcard mode. \code QRegExp rx( "*.html" ); // Invalid regexp: * doesn't quantify anything rx.setWildcard( TRUE ); // Now its a valid wildcard regexp rx.search( "index.html" ); // Returns 0 (matched at position 0) rx.search( "default.htm" ); // Returns -1 (no match) rx.search( "readme.txt" ); // Returns -1 (no match) \endcode Wildcard matching can be convenient because of its simplicity, but any wildcard regex can be defined using full regexps, e.g. .*\.html$. Notice that we can't match both \c .html and \c .htm files with a wildcard unless we use *.htm* which will also match 'test.html.bak'. A full regexp gives us the precision we need, .*\.html?$. QRegExp can match case insensitively using setCaseSensitive(), and can use non-greedy matching, see setMinimal(). By default QRegExp uses full regexps but this can be changed with setWildcard(). Searching can be forward with search() or backward with searchRev(). Captured text can be accessed using capturedTexts() which returns a string list of all captured strings, or using cap() which returns the captured string for the given index. The pos() function takes a match index and returns the position in the string where the match was made (or -1 if there was no match). \sa QRegExpValidator QString QStringList */ static const int NumBadChars = 128; #define BadChar( ch ) ( (ch).cell() % NumBadChars ) static const int NoOccurrence = INT_MAX; static const int EmptyCapture = INT_MAX; static const int InftyLen = INT_MAX; static const int InftyRep = 1000; static const int EOS = -1; #ifndef QT_NO_REGEXP_OPTIM static int engCount = 0; static QArray *noOccurrences = 0; static QArray *firstOccurrenceAtZero = 0; #endif /* Merges two QArrays of ints and puts the result into the first one. */ static void mergeInto( QArray *a, const QArray& b ) { int asize = a->size(); int bsize = b.size(); if ( asize == 0 ) { *a = b.copy(); #ifndef QT_NO_REGEXP_OPTIM } else if ( bsize == 1 && (*a)[asize - 1] < b[0] ) { a->resize( asize + 1 ); (*a)[asize] = b[0]; #endif } else if ( bsize >= 1 ) { int csize = asize + bsize; QArray c( csize ); int i = 0, j = 0, k = 0; while ( i < asize ) { if ( j < bsize ) { if ( (*a)[i] == b[j] ) { i++; csize--; } else if ( (*a)[i] < b[j] ) { c[k++] = (*a)[i++]; } else { c[k++] = b[j++]; } } else { memcpy( c.data() + k, (*a).data() + i, (asize - i) * sizeof(int) ); break; } } c.resize( csize ); if ( j < bsize ) memcpy( c.data() + k, b.data() + j, (bsize - j) * sizeof(int) ); *a = c; } } /* Merges two disjoint QMaps of (int, int) pairs and puts the result into the first one. */ static void mergeInto( QMap *a, const QMap& b ) { QMap::ConstIterator it; for ( it = b.begin(); it != b.end(); ++it ) a->insert( it.key(), *it ); } /* Returns the value associated to key k in QMap m of (int, int) pairs, or 0 if no such value is explicitly present. */ static int at( const QMap& m, int k ) { QMap::ConstIterator it = m.find( k ); if ( it == m.end() ) return 0; else return *it; } #ifndef QT_NO_REGEXP_WILDCARD /* Translates a wildcard pattern to an equivalent regular expression pattern (e.g., *.cpp to .*\.cpp). */ static QString wc2rx( const QString& wc ) { int wclen = wc.length(); QString rx = QString::fromLatin1( "" ); int i = 0; while ( i < wclen ) { QChar c = wc[i++]; switch ( c.unicode() ) { case '*': rx += QString::fromLatin1( ".*" ); break; case '?': rx += QChar( '.' ); break; case '$': case '(': case ')': case '+': case '.': case '\\': case '^': case '{': case '|': case '}': rx += QChar( '\\' ); rx += c; break; case '[': rx += c; if ( wc[i] == QChar('^') ) rx += wc[i++]; if ( i < wclen ) { if ( rx[i] == ']' ) rx += wc[i++]; while ( i < wclen && wc[i] != QChar(']') ) { if ( wc[i] == '\\' ) rx += QChar( '\\' ); rx += wc[i++]; } } break; default: rx += c; } } return rx; } #endif /* The class QRegExpEngine encapsulates a modified nondeterministic finite automaton (NFA). */ class QRegExpEngine : public QShared { public: #ifndef QT_NO_REGEXP_CCLASS /* The class CharClass represents a set of characters, such as can be found in regular expressions (e.g., [a-z] denotes the set {a, b, ..., z}). */ class CharClass { public: CharClass(); CharClass( const CharClass& cc ) { operator=( cc ); } CharClass& operator=( const CharClass& cc ); void clear(); bool negative() const { return n; } void setNegative( bool negative ); void addCategories( int cats ); void addRange( ushort from, ushort to ); void addSingleton( ushort ch ) { addRange( ch, ch ); } bool in( QChar ch ) const; #ifndef QT_NO_REGEXP_OPTIM const QArray& firstOccurrence() const { return occ1; } #endif #if defined(QT_DEBUG) void dump() const; #endif private: /* The struct Range represents a range of characters (e.g., [0-9] denotes range 48 to 57). */ struct Range { ushort from; // 48 ushort to; // 57 }; int c; // character classes QArray r; // character ranges bool n; // negative? #ifndef QT_NO_REGEXP_OPTIM QArray occ1; // first-occurrence array #endif }; #else struct CharClass { int x; // dummy #ifndef QT_NO_REGEXP_OPTIM const QArray& firstOccurrence() const { return *firstOccurrenceAtZero; } #endif }; #endif QRegExpEngine( bool caseSensitive ) { setup( caseSensitive ); } QRegExpEngine( const QString& rx, bool caseSensitive ); #ifndef QT_NO_REGEXP_OPTIM ~QRegExpEngine(); #endif bool isValid() const { return valid; } bool caseSensitive() const { return cs; } int numCaptures() const { return realncap; } QArray match( const QString& str, int pos, bool minimal, bool oneTest ); int matchedLength() const { return mmMatchedLen; } int createState( QChar ch ); int createState( const CharClass& cc ); #ifndef QT_NO_REGEXP_BACKREF int createState( int bref ); #endif void addCatTransitions( const QArray& from, const QArray& to ); #ifndef QT_NO_REGEXP_CAPTURE void addPlusTransitions( const QArray& from, const QArray& to, int atom ); #endif #ifndef QT_NO_REGEXP_ANCHOR_ALT int anchorAlternation( int a, int b ); int anchorConcatenation( int a, int b ); #else int anchorAlternation( int a, int b ) { return a & b; } int anchorConcatenation( int a, int b ) { return a | b; } #endif void addAnchors( int from, int to, int a ); #ifndef QT_NO_REGEXP_OPTIM void setupGoodStringHeuristic( int earlyStart, int lateStart, const QString& str ); void setupBadCharHeuristic( int minLen, const QArray& firstOcc ); void heuristicallyChooseHeuristic(); #endif #if defined(QT_DEBUG) void dump() const; #endif private: enum { CharClassBit = 0x10000, BackRefBit = 0x20000 }; /* The struct State represents one state in a modified NFA. The input characters matched are stored in the state instead of on the transitions, something possible for an automaton constructed from a regular expression. */ struct State { #ifndef QT_NO_REGEXP_CAPTURE int atom; // which atom does this state belong to? #endif int match; // what does it match? (see CharClassBit and BackRefBit) QArray outs; // out-transitions QMap *reenter; // atoms reentered when transiting out QMap *anchors; // anchors met when transiting out #ifndef QT_NO_REGEXP_CAPTURE State( int a, int m ) : atom( a ), match( m ), reenter( 0 ), anchors( 0 ) { } #else State( int m ) : match( m ), reenter( 0 ), anchors( 0 ) { } #endif ~State() { delete reenter; delete anchors; } }; #ifndef QT_NO_REGEXP_LOOKAHEAD /* The struct Lookahead represents a lookahead a la Perl (e.g., (?=foo) and (?!bar)). */ struct Lookahead { QRegExpEngine *eng; // NFA representing the embedded regular expression bool neg; // negative lookahead? Lookahead( QRegExpEngine *eng0, bool neg0 ) : eng( eng0 ), neg( neg0 ) { } ~Lookahead() { delete eng; } }; #endif #ifndef QT_NO_REGEXP_CAPTURE /* The struct Atom represents one node in the hierarchy of regular expression atoms. */ struct Atom { int parent; // index of parent in array of atoms int capture; // index of capture, from 1 to ncap }; #endif #ifndef QT_NO_REGEXP_ANCHOR_ALT /* The struct AnchorAlternation represents a pair of anchors with OR semantics. */ struct AnchorAlternation { int a; // this anchor... int b; // ...or this one }; #endif enum { InitialState = 0, FinalState = 1 }; void setup( bool caseSensitive ); int setupState( int match ); /* Let's hope that 13 lookaheads and 14 back-references are enough. */ enum { MaxLookaheads = 13, MaxBackRefs = 14 }; enum { Anchor_Dollar = 0x00000001, Anchor_Caret = 0x00000002, Anchor_Word = 0x00000004, Anchor_NonWord = 0x00000008, Anchor_FirstLookahead = 0x00000010, Anchor_BackRef1Empty = Anchor_FirstLookahead << MaxLookaheads, Anchor_BackRef0Empty = Anchor_BackRef1Empty >> 1, Anchor_Alternation = Anchor_BackRef1Empty << MaxBackRefs, Anchor_LookaheadMask = ( Anchor_FirstLookahead - 1 ) ^ ( (Anchor_FirstLookahead << MaxLookaheads) - 1 ) }; #ifndef QT_NO_REGEXP_CAPTURE int startAtom( bool capture ); void finishAtom( int atom ) { cf = f[atom].parent; } #endif #ifndef QT_NO_REGEXP_LOOKAHEAD int addLookahead( QRegExpEngine *eng, bool negative ); #endif #ifndef QT_NO_REGEXP_CAPTURE bool isBetterCapture( const int *begin1, const int *end1, const int *begin2, const int *end2 ); #endif bool testAnchor( int i, int a, const int *capBegin ); #ifndef QT_NO_REGEXP_OPTIM bool goodStringMatch(); bool badCharMatch(); #else bool bruteMatch(); #endif bool matchHere(); QVector s; // array of states int ns; // number of states #ifndef QT_NO_REGEXP_CAPTURE QArray f; // atom hierarchy int nf; // number of atoms int cf; // current atom #endif int realncap; // number of captures, seen from the outside int ncap; // number of captures, seen from the inside #ifndef QT_NO_REGEXP_CCLASS QVector cl; // array of character classes #endif #ifndef QT_NO_REGEXP_LOOKAHEAD QVector ahead; // array of lookaheads #endif #ifndef QT_NO_REGEXP_ANCHOR_ALT QArray aa; // array of (a, b) pairs of anchors #endif #ifndef QT_NO_REGEXP_OPTIM bool caretAnchored; // does the regexp start with ^? #endif bool valid; // is the regular expression valid? bool cs; // case sensitive? #ifndef QT_NO_REGEXP_BACKREF int nbrefs; // number of back-references #endif #ifndef QT_NO_REGEXP_OPTIM bool useGoodStringHeuristic; // use goodStringMatch? otherwise badCharMatch int goodEarlyStart; // the index where goodStr can first occur in a match int goodLateStart; // the index where goodStr can last occur in a match QString goodStr; // the string that any match has to contain int minl; // the minimum length of a match QArray occ1; // first-occurrence array #endif /* The class Box is an abstraction for a regular expression fragment. It can also be seen as one node in the syntax tree of a regular expression with synthetized attributes. It's interface is ugly for performance reasons. */ class Box { public: Box( QRegExpEngine *engine ); Box( const Box& b ) { operator=( b ); } Box& operator=( const Box& b ); void clear() { operator=(Box(eng)); } void set( QChar ch ); void set( const CharClass& cc ); #ifndef QT_NO_REGEXP_BACKREF void set( int bref ); #endif void cat( const Box& b ); void orx( const Box& b ); void plus( int atom ); void opt(); void catAnchor( int a ); #ifndef QT_NO_REGEXP_OPTIM void setupHeuristics(); #endif #if defined(QT_DEBUG) void dump() const; #endif private: void addAnchorsToEngine( const Box& to ) const; QRegExpEngine *eng; // the automaton under construction QArray ls; // the left states (firstpos) QArray rs; // the right states (lastpos) QMap lanchors; // the left anchors QMap ranchors; // the right anchors int skipanchors; // the anchors to match if the box is skipped #ifndef QT_NO_REGEXP_OPTIM int earlyStart; // the index where str can first occur int lateStart; // the index where str can last occur QString str; // a string that has to occur in any match QString leftStr; // a string occurring at the left of this box QString rightStr; // a string occurring at the right of this box int maxl; // the maximum length of this box (possibly InftyLen) #endif int minl; // the minimum length of this box #ifndef QT_NO_REGEXP_OPTIM QArray occ1; // first-occurrence array #endif }; friend class Box; /* This is the lexical analyzer for regular expressions. */ enum { Tok_Eos, Tok_Dollar, Tok_LeftParen, Tok_MagicLeftParen, Tok_PosLookahead, Tok_NegLookahead, Tok_RightParen, Tok_CharClass, Tok_Caret, Tok_Quantifier, Tok_Bar, Tok_Word, Tok_NonWord, Tok_Char = 0x10000, Tok_BackRef = 0x20000 }; int getChar(); int getEscape(); #ifndef QT_NO_REGEXP_INTERVAL int getRep( int def ); #endif #ifndef QT_NO_REGEXP_LOOKAHEAD void skipChars( int n ); #endif void startTokenizer( const QChar *rx, int len ); int getToken(); const QChar *yyIn; // a pointer to the input regular expression pattern int yyPos0; // the position of yyTok in the input pattern int yyPos; // the position of the next character to read int yyLen; // the length of yyIn int yyCh; // the last character read CharClass *yyCharClass; // attribute for Tok_CharClass tokens int yyMinRep; // attribute for Tok_Quantifier int yyMaxRep; // ditto bool yyError; // syntax error or overflow during parsing? /* This is the syntactic analyzer for regular expressions. */ int parse( const QChar *rx, int len ); void parseAtom( Box *box ); void parseFactor( Box *box ); void parseTerm( Box *box ); void parseExpression( Box *box ); int yyTok; // the last token read bool yyMayCapture; // set this to FALSE to disable capturing /* This is the engine state during matching. */ const QString *mmStr; // a pointer to the input QString const QChar *mmIn; // a pointer to the input string data int mmPos; // the current position in the string int mmLen; // the length of the input string bool mmMinimal; // minimal matching? QArray mmCaptured; // an array of pairs (start, len) QArray mmCapturedNoMatch; // an array of pairs (-1, -1) QArray mmBigArray; // big QArray array int *mmInNextStack; // is state is mmNextStack? int *mmCurStack; // stack of current states int *mmNextStack; // stack of next states int *mmCurCapBegin; // start of current states' captures int *mmNextCapBegin; // start of next states' captures int *mmCurCapEnd; // end of current states' captures int *mmNextCapEnd; // end of next states' captures int *mmTempCapBegin; // start of temporary captures int *mmTempCapEnd; // end of temporary captures int *mmCapBegin; // start of captures for a next state int *mmCapEnd; // end of captures for a next state int *mmSlideTab; // bump-along slide table for bad-character heuristic int mmSlideTabSize; // size of slide table #ifndef QT_NO_REGEXP_BACKREF QIntDict mmSleeping; // dictionary of back-reference sleepers #endif int mmMatchedLen; // length of match or of matched string for partial match }; QRegExpEngine::QRegExpEngine( const QString& rx, bool caseSensitive ) #ifndef QT_NO_REGEXP_BACKREF : mmSleeping( 101 ) #endif { setup( caseSensitive ); valid = ( parse(rx.unicode(), rx.length()) == (int) rx.length() ); } #ifndef QT_NO_REGEXP_OPTIM QRegExpEngine::~QRegExpEngine() { if ( --engCount == 0 ) { delete noOccurrences; noOccurrences = 0; delete firstOccurrenceAtZero; firstOccurrenceAtZero = 0; } } #endif /* Tries to match in str and returns an array of (begin, length) pairs for captured text. If there is no match, all pairs are (-1, -1). */ QArray QRegExpEngine::match( const QString& str, int pos, bool minimal, bool oneTest ) { mmStr = &str; mmIn = str.unicode(); if ( mmIn == 0 ) mmIn = &QChar::null; mmPos = pos; mmLen = str.length(); mmMinimal = minimal; mmMatchedLen = 0; bool matched = FALSE; if ( valid && mmPos >= 0 && mmPos <= mmLen ) { #ifndef QT_NO_REGEXP_OPTIM if ( mmPos <= mmLen - minl ) { if ( caretAnchored || oneTest ) matched = matchHere(); else if ( useGoodStringHeuristic ) matched = goodStringMatch(); else matched = badCharMatch(); } #else matched = oneTest ? matchHere() : bruteMatch(); #endif } if ( matched ) { mmCaptured.detach(); mmCaptured[0] = mmPos; mmCaptured[1] = mmMatchedLen; for ( int j = 0; j < realncap; j++ ) { int len = mmCapEnd[j] - mmCapBegin[j]; mmCaptured[2 + 2 * j] = len > 0 ? mmPos + mmCapBegin[j] : 0; mmCaptured[2 + 2 * j + 1] = len; } return mmCaptured; } else { return mmCapturedNoMatch; } } /* The three following functions add one state to the automaton and return the number of the state. */ int QRegExpEngine::createState( QChar ch ) { return setupState( ch.unicode() ); } int QRegExpEngine::createState( const CharClass& cc ) { #ifndef QT_NO_REGEXP_CCLASS int n = cl.size(); cl.resize( n + 1 ); cl.insert( n, new CharClass(cc) ); return setupState( CharClassBit | n ); #else Q_UNUSED( cc ); return setupState( CharClassBit ); #endif } #ifndef QT_NO_REGEXP_BACKREF int QRegExpEngine::createState( int bref ) { if ( bref > nbrefs ) { nbrefs = bref; if ( nbrefs > MaxBackRefs ) { yyError = TRUE; return 0; } } return setupState( BackRefBit | bref ); } #endif /* The two following functions add a transition between all pairs of states (i, j) where i is fond in from, and j is found in to. Cat-transitions are distinguished from plus-transitions for capturing. */ void QRegExpEngine::addCatTransitions( const QArray& from, const QArray& to ) { for ( int i = 0; i < (int) from.size(); i++ ) { State *st = s[from[i]]; mergeInto( &st->outs, to ); } } #ifndef QT_NO_REGEXP_CAPTURE void QRegExpEngine::addPlusTransitions( const QArray& from, const QArray& to, int atom ) { for ( int i = 0; i < (int) from.size(); i++ ) { State *st = s[from[i]]; QArray oldOuts = st->outs.copy(); mergeInto( &st->outs, to ); if ( f[atom].capture >= 0 ) { if ( st->reenter == 0 ) st->reenter = new QMap; for ( int j = 0; j < (int) to.size(); j++ ) { if ( !st->reenter->contains(to[j]) && oldOuts.bsearch(to[j]) < 0 ) st->reenter->insert( to[j], atom ); } } } } #endif #ifndef QT_NO_REGEXP_ANCHOR_ALT /* Returns an anchor that means a OR b. */ int QRegExpEngine::anchorAlternation( int a, int b ) { if ( ((a & b) == a || (a & b) == b) && ((a | b) & Anchor_Alternation) == 0 ) return a & b; int n = aa.size(); aa.resize( n + 1 ); aa[n].a = a; aa[n].b = b; return Anchor_Alternation | n; } /* Returns an anchor that means a AND b. */ int QRegExpEngine::anchorConcatenation( int a, int b ) { if ( ((a | b) & Anchor_Alternation) == 0 ) return a | b; if ( (b & Anchor_Alternation) != 0 ) qSwap( a, b ); int aprime = anchorConcatenation( aa[a ^ Anchor_Alternation].a, b ); int bprime = anchorConcatenation( aa[a ^ Anchor_Alternation].b, b ); return anchorAlternation( aprime, bprime ); } #endif /* Adds anchor a on a transition caracterised by its from state and its to state. */ void QRegExpEngine::addAnchors( int from, int to, int a ) { State *st = s[from]; if ( st->anchors == 0 ) st->anchors = new QMap; if ( st->anchors->contains(to) ) a = anchorAlternation( (*st->anchors)[to], a ); st->anchors->insert( to, a ); } #ifndef QT_NO_REGEXP_OPTIM /* The two following functions provide the engine with the information needed by its matching heuristics. */ void QRegExpEngine::setupGoodStringHeuristic( int earlyStart, int lateStart, const QString& str ) { goodEarlyStart = earlyStart; goodLateStart = lateStart; goodStr = cs ? str : str.lower(); } void QRegExpEngine::setupBadCharHeuristic( int minLen, const QArray& firstOcc ) { minl = minLen; occ1 = cs ? firstOcc : *firstOccurrenceAtZero; } /* This function chooses between the good-string and the bad-character heuristics. It computes two scores and chooses the heuristic with the highest score. Here are some common-sense constraints on the scores that should be respected if the formulas are ever modified: (1) If goodStr is empty, the good-string heuristic scores 0. (2) If the search is case insensitive, the good-string heuristic should be used, unless it scores 0. (Case insensitivity turns all entries of occ1 to 0.) (3) If (goodLateStart - goodEarlyStart) is big, the good-string heuristic should score less. */ void QRegExpEngine::heuristicallyChooseHeuristic() { int i; if ( minl == 0 ) return; /* Magic formula: The good string has to constitute a good proportion of the minimum-length string, and appear at a more-or-less known index. */ int goodStringScore = ( 64 * goodStr.length() / minl ) - ( goodLateStart - goodEarlyStart ); /* Less magic formula: We pick a couple of characters at random, and check whether they are good or bad. */ int badCharScore = 0; int step = QMAX( 1, NumBadChars / 32 ); for ( i = 1; i < NumBadChars; i += step ) { if ( occ1[i] == NoOccurrence ) badCharScore += minl; else badCharScore += occ1[i]; } badCharScore /= minl; useGoodStringHeuristic = ( goodStringScore > badCharScore ); } #endif #if defined(QT_DEBUG) void QRegExpEngine::dump() const { int i, j; qDebug( "Case %ssensitive engine", cs ? "" : "in" ); qDebug( " States" ); for ( i = 0; i < ns; i++ ) { qDebug( " %d%s", i, i == InitialState ? " (initial)" : i == FinalState ? " (final)" : "" ); #ifndef QT_NO_REGEXP_CAPTURE qDebug( " in atom %d", s[i]->atom ); #endif int m = s[i]->match; if ( (m & CharClassBit) != 0 ) { qDebug( " match character class %d", m ^ CharClassBit ); #ifndef QT_NO_REGEXP_CCLASS cl[m ^ CharClassBit]->dump(); #else qDebug( " negative character class" ); #endif } else if ( (m & BackRefBit) != 0 ) { qDebug( " match back-reference %d", m ^ BackRefBit ); } else if ( m >= 0x20 && m <= 0x7e ) { qDebug( " match 0x%.4x (%c)", m, m ); } else { qDebug( " match 0x%.4x", m ); } for ( j = 0; j < (int) s[i]->outs.size(); j++ ) { int next = s[i]->outs[j]; qDebug( " -> %d", next ); if ( s[i]->reenter != 0 && s[i]->reenter->contains(next) ) qDebug( " [reenter %d]", (*s[i]->reenter)[next] ); if ( s[i]->anchors != 0 && at(*s[i]->anchors, next) != 0 ) qDebug( " [anchors 0x%.8x]", (*s[i]->anchors)[next] ); } } #ifndef QT_NO_REGEXP_CAPTURE if ( nf > 0 ) { qDebug( " Atom Parent Capture" ); for ( i = 0; i < nf; i++ ) qDebug( " %6d %6d %6d", i, f[i].parent, f[i].capture ); } #endif #ifndef QT_NO_REGEXP_ANCHOR_ALT for ( i = 0; i < (int) aa.size(); i++ ) qDebug( " Anchor alternation 0x%.8x: 0x%.8x 0x%.9x", i, aa[i].a, aa[i].b ); #endif } #endif void QRegExpEngine::setup( bool caseSensitive ) { #ifndef QT_NO_REGEXP_OPTIM if ( engCount++ == 0 ) { noOccurrences = new QArray( NumBadChars ); firstOccurrenceAtZero = new QArray( NumBadChars ); noOccurrences->fill( NoOccurrence ); firstOccurrenceAtZero->fill( 0 ); } #endif s.setAutoDelete( TRUE ); s.resize( 32 ); ns = 0; #ifndef QT_NO_REGEXP_CAPTURE f.resize( 32 ); nf = 0; cf = -1; #endif realncap = 0; ncap = 0; #ifndef QT_NO_REGEXP_CCLASS cl.setAutoDelete( TRUE ); #endif #ifndef QT_NO_REGEXP_LOOKAHEAD ahead.setAutoDelete( TRUE ); #endif #ifndef QT_NO_REGEXP_OPTIM caretAnchored = TRUE; #endif valid = FALSE; cs = caseSensitive; #ifndef QT_NO_REGEXP_BACKREF nbrefs = 0; #endif #ifndef QT_NO_REGEXP_OPTIM useGoodStringHeuristic = FALSE; minl = 0; occ1 = *firstOccurrenceAtZero; #endif mmCapturedNoMatch.fill( -1, 2 ); } int QRegExpEngine::setupState( int match ) { if ( (ns & (ns + 1)) == 0 && ns + 1 >= (int) s.size() ) s.resize( (ns + 1) << 1 ); #ifndef QT_NO_REGEXP_CAPTURE s.insert( ns, new State(cf, match) ); #else s.insert( ns, new State(match) ); #endif return ns++; } #ifndef QT_NO_REGEXP_CAPTURE /* Functions startAtom() and finishAtom() should be called to delimit atoms. When a state is created, it is assigned to the current atom. The information is later used for capturing. */ int QRegExpEngine::startAtom( bool capture ) { if ( (nf & (nf + 1)) == 0 && nf + 1 >= (int) f.size() ) f.resize( (nf + 1) << 1 ); f[nf].parent = cf; cf = nf++; f[cf].capture = capture ? ncap++ : -1; return cf; } #endif #ifndef QT_NO_REGEXP_LOOKAHEAD /* Creates a lookahead anchor. */ int QRegExpEngine::addLookahead( QRegExpEngine *eng, bool negative ) { int n = ahead.size(); if ( n == MaxLookaheads ) { yyError = TRUE; return 0; } ahead.resize( n + 1 ); ahead.insert( n, new Lookahead(eng, negative) ); return Anchor_FirstLookahead << n; } #endif #ifndef QT_NO_REGEXP_CAPTURE /* We want the longest leftmost captures. */ bool QRegExpEngine::isBetterCapture( const int *begin1, const int *end1, const int *begin2, const int *end2 ) { for ( int i = 0; i < ncap; i++ ) { int delta = begin2[i] - begin1[i]; // it has to start early... if ( delta == 0 ) delta = end1[i] - end2[i]; // ...and end late (like a party) if ( delta != 0 ) return delta > 0; } return FALSE; } #endif /* Returns TRUE if anchor a matches at position mmPos + i in the input string, otherwise FALSE. */ bool QRegExpEngine::testAnchor( int i, int a, const int *capBegin ) { int j; #ifndef QT_NO_REGEXP_ANCHOR_ALT if ( (a & Anchor_Alternation) != 0 ) { return testAnchor( i, aa[a ^ Anchor_Alternation].a, capBegin ) || testAnchor( i, aa[a ^ Anchor_Alternation].b, capBegin ); } #endif if ( (a & Anchor_Caret) != 0 ) { if ( mmPos + i != 0 ) return FALSE; } if ( (a & Anchor_Dollar) != 0 ) { if ( mmPos + i != mmLen ) return FALSE; } #ifndef QT_NO_REGEXP_ESCAPE if ( (a & (Anchor_Word | Anchor_NonWord)) != 0 ) { bool before = FALSE, after = FALSE; if ( mmPos + i != 0 ) before = mmIn[mmPos + i - 1].isLetterOrNumber(); if ( mmPos + i != mmLen ) after = mmIn[mmPos + i].isLetterOrNumber(); if ( (a & Anchor_Word) != 0 && (before == after) ) return FALSE; if ( (a & Anchor_NonWord) != 0 && (before != after) ) return FALSE; } #endif #ifndef QT_NO_REGEXP_LOOKAHEAD bool catchx = TRUE; if ( (a & Anchor_LookaheadMask) != 0 ) { QConstString cstr = QConstString( (QChar *) mmIn + mmPos + i, mmLen - mmPos - i ); for ( j = 0; j < (int) ahead.size(); j++ ) { if ( (a & (Anchor_FirstLookahead << j)) != 0 ) { catchx = ( ahead[j]->eng->match(cstr.string(), 0, TRUE, TRUE)[0] == 0 ); if ( catchx == ahead[j]->neg ) return FALSE; } } } #endif #ifndef QT_NO_REGEXP_CAPTURE #ifndef QT_NO_REGEXP_BACKREF for ( j = 0; j < nbrefs; j++ ) { if ( (a & (Anchor_BackRef1Empty << j)) != 0 ) { if ( capBegin[j] != EmptyCapture ) return FALSE; } } #endif #endif return TRUE; } #ifndef QT_NO_REGEXP_OPTIM /* The three following functions are what Jeffrey Friedl would call transmissions (or bump-alongs). Using one or the other should make no difference, except in performance. */ bool QRegExpEngine::goodStringMatch() { int k = mmPos + goodEarlyStart; while ( (k = mmStr->find(goodStr, k, cs)) != -1 ) { int from = k - goodLateStart; int to = k - goodEarlyStart; if ( from > mmPos ) mmPos = from; while ( mmPos <= to ) { if ( matchHere() ) return TRUE; mmPos++; } k++; } return FALSE; } bool QRegExpEngine::badCharMatch() { int slideHead = 0; int slideNext = 0; int i; int lastPos = mmLen - minl; memset( mmSlideTab, 0, mmSlideTabSize * sizeof(int) ); /* Set up the slide table, used for the bad-character heuristic, using the table of first occurrence of each character. */ for ( i = 0; i < minl; i++ ) { int sk = occ1[BadChar(mmIn[mmPos + i])]; if ( sk == NoOccurrence ) sk = i + 1; if ( sk > 0 ) { int k = i + 1 - sk; if ( k < 0 ) { sk = i + 1; k = 0; } if ( sk > mmSlideTab[k] ) mmSlideTab[k] = sk; } } if ( mmPos > lastPos ) return FALSE; while ( TRUE ) { if ( ++slideNext >= mmSlideTabSize ) slideNext = 0; if ( mmSlideTab[slideHead] > 0 ) { if ( mmSlideTab[slideHead] - 1 > mmSlideTab[slideNext] ) mmSlideTab[slideNext] = mmSlideTab[slideHead] - 1; mmSlideTab[slideHead] = 0; } else { if ( matchHere() ) return TRUE; } if ( mmPos == lastPos ) break; /* Update the slide table. This code has much in common with the initialization code. */ int sk = occ1[BadChar(mmIn[mmPos + minl])]; if ( sk == NoOccurrence ) { mmSlideTab[slideNext] = minl; } else if ( sk > 0 ) { int k = slideNext + minl - sk; if ( k >= mmSlideTabSize ) k -= mmSlideTabSize; if ( sk > mmSlideTab[k] ) mmSlideTab[k] = sk; } slideHead = slideNext; mmPos++; } return FALSE; } #else bool QRegExpEngine::bruteMatch() { while ( mmPos <= mmLen ) { if ( matchHere() ) return TRUE; mmPos++; } return FALSE; } #endif /* Here's the core of the engine. It tries to do a match here and now. */ bool QRegExpEngine::matchHere() { int ncur = 1, nnext = 0; int i = 0, j, k, m; bool match = FALSE; mmMatchedLen = -1; mmCurStack[0] = InitialState; #ifndef QT_NO_REGEXP_CAPTURE if ( ncap > 0 ) { for ( j = 0; j < ncap; j++ ) { mmCurCapBegin[j] = EmptyCapture; mmCurCapEnd[j] = EmptyCapture; } } #endif #ifndef QT_NO_REGEXP_BACKREF int *zzZ = 0; while ( (ncur > 0 || mmSleeping.count() > 0) && i <= mmLen - mmPos && !match ) #else while ( ncur > 0 && i <= mmLen - mmPos && !match ) #endif { int ch = ( i < mmLen - mmPos ) ? mmIn[mmPos + i].unicode() : 0; for ( j = 0; j < ncur; j++ ) { int cur = mmCurStack[j]; State *scur = s[cur]; QArray& outs = scur->outs; for ( k = 0; k < (int) outs.size(); k++ ) { int next = outs[k]; State *snext = s[next]; bool in = TRUE; #ifndef QT_NO_REGEXP_BACKREF int needSomeSleep = 0; #endif /* First, check if the anchors are anchored properly. */ if ( scur->anchors != 0 ) { int a = at( *scur->anchors, next ); if ( a != 0 && !testAnchor(i, a, mmCurCapBegin + j * ncap) ) in = FALSE; } /* If indeed they are, check if the input character is correct for this transition. */ if ( in ) { m = snext->match; if ( (m & (CharClassBit | BackRefBit)) == 0 ) { if ( cs ) in = ( m == ch ); else in = ( QChar(m).lower() == QChar(ch).lower() ); } else if ( next == FinalState ) { mmMatchedLen = i; match = mmMinimal; in = TRUE; } else if ( (m & CharClassBit) != 0 ) { #ifndef QT_NO_REGEXP_CCLASS const CharClass *cc = cl[m ^ CharClassBit]; if ( cs ) in = cc->in( ch ); else if ( cc->negative() ) in = cc->in( QChar(ch).lower() ) && cc->in( QChar(ch).upper() ); else in = cc->in( QChar(ch).lower() ) || cc->in( QChar(ch).upper() ); #endif #ifndef QT_NO_REGEXP_BACKREF } else { /* ( (m & BackRefBit) != 0 ) */ int bref = m ^ BackRefBit; int ell = j * ncap + ( bref - 1 ); in = bref <= ncap && mmCurCapBegin[ell] != EmptyCapture; if ( in ) { if ( cs ) in = ( mmIn[mmPos + mmCurCapBegin[ell]] == QChar(ch) ); else in = ( mmIn[mmPos + mmCurCapBegin[ell]].lower() == QChar(ch).lower() ); } if ( in ) { int delta; if ( mmCurCapEnd[ell] == EmptyCapture ) delta = i - mmCurCapBegin[ell]; else delta = mmCurCapEnd[ell] - mmCurCapBegin[ell]; in = ( delta <= mmLen - mmPos ); if ( in && delta > 1 ) { int n; if ( cs ) { for ( n = 1; n < delta; n++ ) { if ( mmIn[mmPos + mmCurCapBegin[ell] + n] != mmIn[mmPos + i + n] ) break; } } else { for ( n = 1; n < delta; n++ ) { QChar a = mmIn[mmPos + mmCurCapBegin[ell] + n]; QChar b = mmIn[mmPos + i + n]; if ( a.lower() != b.lower() ) break; } } in = ( n == delta ); if ( in ) needSomeSleep = delta - 1; } } #endif } } /* All is right. We must now update our data structures. */ if ( in ) { #ifndef QT_NO_REGEXP_CAPTURE int *capBegin, *capEnd; #endif /* If the next state was not encountered yet, all is fine. */ if ( (m = mmInNextStack[next]) == -1 ) { m = nnext++; mmNextStack[m] = next; mmInNextStack[next] = m; #ifndef QT_NO_REGEXP_CAPTURE capBegin = mmNextCapBegin + m * ncap; capEnd = mmNextCapEnd + m * ncap; /* Otherwise, we'll first maintain captures in temporary arrays, and decide at the end whether it's best to keep the previous capture zones or the new ones. */ } else { capBegin = mmTempCapBegin; capEnd = mmTempCapEnd; #endif } #ifndef QT_NO_REGEXP_CAPTURE /* Updating the capture zones is much of a task. */ if ( ncap > 0 ) { memcpy( capBegin, mmCurCapBegin + j * ncap, ncap * sizeof(int) ); memcpy( capEnd, mmCurCapEnd + j * ncap, ncap * sizeof(int) ); int c = scur->atom, n = snext->atom; int p = -1, q = -1; int cap; /* Lemma 1. For any x in the range [0..nf), we have f[x].parent < x. Proof. By looking at startAtom(), it is clear that cf < nf holds all the time, and thus that f[nf].parent < nf. */ /* If we are reentering an atom, we empty all capture zones inside it. */ if ( scur->reenter != 0 && (q = at(*scur->reenter, next)) != 0 ) { QBitArray b; b.fill( FALSE, nf ); b.setBit( q, TRUE ); for ( int ell = q + 1; ell < nf; ell++ ) { if ( b.testBit(f[ell].parent) ) { b.setBit( ell, TRUE ); cap = f[ell].capture; if ( cap >= 0 ) { capBegin[cap] = EmptyCapture; capEnd[cap] = EmptyCapture; } } } p = f[q].parent; /* Otherwise, close the capture zones we are leaving. We are leaving f[c].capture, f[f[c].parent].capture, f[f[f[c].parent].parent].capture, ..., until f[x].capture, with x such that f[x].parent is the youngest common ancestor for c and n. We go up along c's and n's ancestry until we find x. */ } else { p = c; q = n; while ( p != q ) { if ( p > q ) { cap = f[p].capture; if ( cap >= 0 ) { if ( capBegin[cap] == i ) { capBegin[cap] = EmptyCapture; capEnd[cap] = EmptyCapture; } else { capEnd[cap] = i; } } p = f[p].parent; } else { q = f[q].parent; } } } /* In any case, we now open the capture zones we are entering. We work upwards from n until we reach p (the parent of the atom we reenter or the youngest common ancestor). */ while ( n > p ) { cap = f[n].capture; if ( cap >= 0 ) { capBegin[cap] = i; capEnd[cap] = EmptyCapture; } n = f[n].parent; } /* If the next state was already in mmNextStack, we must choose carefully which capture zones we want to keep. */ if ( capBegin == mmTempCapBegin && isBetterCapture(capBegin, capEnd, mmNextCapBegin + m * ncap, mmNextCapEnd + m * ncap) ) { memcpy( mmNextCapBegin + m * ncap, capBegin, ncap * sizeof(int) ); memcpy( mmNextCapEnd + m * ncap, capEnd, ncap * sizeof(int) ); } } #ifndef QT_NO_REGEXP_BACKREF /* We are done with updating the capture zones. It's now time to put the next state to sleep, if it needs to, and to remove it from mmNextStack. */ if ( needSomeSleep > 0 ) { zzZ = new int[1 + 2 * ncap]; zzZ[0] = next; if ( ncap > 0 ) { memcpy( zzZ + 1, capBegin, ncap * sizeof(int) ); memcpy( zzZ + 1 + ncap, capEnd, ncap * sizeof(int) ); } mmInNextStack[mmNextStack[--nnext]] = -1; mmSleeping.insert( i + needSomeSleep, zzZ ); } #endif #endif } } } #ifndef QT_NO_REGEXP_CAPTURE /* If we reached the final state, hurray! Copy the captured zone. */ if ( ncap > 0 && (m = mmInNextStack[FinalState]) != -1 ) { memcpy( mmCapBegin, mmNextCapBegin + m * ncap, ncap * sizeof(int) ); memcpy( mmCapEnd, mmNextCapEnd + m * ncap, ncap * sizeof(int) ); } #ifndef QT_NO_REGEXP_BACKREF /* It's time to wake up the sleepers. */ if ( mmSleeping.count() > 0 ) { while ( (zzZ = mmSleeping.take(i)) != 0 ) { int next = zzZ[0]; int *capBegin = zzZ + 1; int *capEnd = zzZ + 1 + ncap; bool copyOver = TRUE; if ( (m = mmInNextStack[zzZ[0]]) == -1 ) { m = nnext++; mmNextStack[m] = next; mmInNextStack[next] = m; } else { copyOver = isBetterCapture( mmNextCapBegin + m * ncap, mmNextCapEnd + m * ncap, capBegin, capEnd ); } if ( copyOver ) { memcpy( mmNextCapBegin + m * ncap, capBegin, ncap * sizeof(int) ); memcpy( mmNextCapEnd + m * ncap, capEnd, ncap * sizeof(int) ); } delete[] zzZ; } } #endif #endif for ( j = 0; j < nnext; j++ ) mmInNextStack[mmNextStack[j]] = -1; qSwap( mmCurStack, mmNextStack ); #ifndef QT_NO_REGEXP_CAPTURE qSwap( mmCurCapBegin, mmNextCapBegin ); qSwap( mmCurCapEnd, mmNextCapEnd ); #endif ncur = nnext; nnext = 0; i++; } #ifndef QT_NO_REGEXP_BACKREF /* If minimal matching is enabled, we might have some sleepers left. */ while ( !mmSleeping.isEmpty() ) { zzZ = mmSleeping.take( *QIntDictIterator(mmSleeping) ); delete[] zzZ; } #endif match = ( mmMatchedLen >= 0 ); if ( !match ) mmMatchedLen = i - 1; return match; } #ifndef QT_NO_REGEXP_CCLASS QRegExpEngine::CharClass::CharClass() : c( 0 ), n( FALSE ) #ifndef QT_NO_REGEXP_OPTIM , occ1( *noOccurrences ) #endif { } QRegExpEngine::CharClass& QRegExpEngine::CharClass::operator=( const CharClass& cc ) { c = cc.c; r = cc.r.copy(); n = cc.n; #ifndef QT_NO_REGEXP_OPTIM occ1 = cc.occ1; #endif return *this; } void QRegExpEngine::CharClass::clear() { c = 0; r.resize( 0 ); n = FALSE; } void QRegExpEngine::CharClass::setNegative( bool negative ) { n = negative; #ifndef QT_NO_REGEXP_OPTIM occ1 = *firstOccurrenceAtZero; #endif } void QRegExpEngine::CharClass::addCategories( int cats ) { c |= cats; #ifndef QT_NO_REGEXP_OPTIM occ1 = *firstOccurrenceAtZero; #endif } void QRegExpEngine::CharClass::addRange( ushort from, ushort to ) { if ( from > to ) qSwap( from, to ); int n = r.size(); r.resize( n + 1 ); r[n].from = from; r[n].to = to; #ifndef QT_NO_REGEXP_OPTIM int i; if ( to - from < NumBadChars ) { occ1.detach(); if ( from % NumBadChars <= to % NumBadChars ) { for ( i = from % NumBadChars; i <= to % NumBadChars; i++ ) occ1[i] = 0; } else { for ( i = 0; i <= to % NumBadChars; i++ ) occ1[i] = 0; for ( i = from % NumBadChars; i < NumBadChars; i++ ) occ1[i] = 0; } } else { occ1 = *firstOccurrenceAtZero; } #endif } bool QRegExpEngine::CharClass::in( QChar ch ) const { #ifndef QT_NO_REGEXP_OPTIM if ( occ1[BadChar(ch)] == NoOccurrence ) return n; #endif if ( c != 0 && (c & (1 << (int) ch.category())) != 0 ) return !n; for ( int i = 0; i < (int) r.size(); i++ ) { if ( ch.unicode() >= r[i].from && ch.unicode() <= r[i].to ) return !n; } return n; } #if defined(QT_DEBUG) void QRegExpEngine::CharClass::dump() const { int i; qDebug( " %stive character class", n ? "nega" : "posi" ); #ifndef QT_NO_REGEXP_CCLASS if ( c != 0 ) qDebug( " categories 0x%.8x", c ); #endif for ( i = 0; i < (int) r.size(); i++ ) qDebug( " 0x%.4x through 0x%.4x", r[i].from, r[i].to ); } #endif #endif QRegExpEngine::Box::Box( QRegExpEngine *engine ) : eng( engine ), skipanchors( 0 ) #ifndef QT_NO_REGEXP_OPTIM , earlyStart( 0 ), lateStart( 0 ), maxl( 0 ), occ1( *noOccurrences ) #endif { minl = 0; } QRegExpEngine::Box& QRegExpEngine::Box::operator=( const Box& b ) { eng = b.eng; ls = b.ls; rs = b.rs; lanchors = b.lanchors; ranchors = b.ranchors; skipanchors = b.skipanchors; #ifndef QT_NO_REGEXP_OPTIM earlyStart = b.earlyStart; lateStart = b.lateStart; str = b.str; leftStr = b.leftStr; rightStr = b.rightStr; maxl = b.maxl; occ1 = b.occ1; #endif minl = b.minl; return *this; } void QRegExpEngine::Box::set( QChar ch ) { ls.resize( 1 ); ls[0] = eng->createState( ch ); rs = ls; rs.detach(); #ifndef QT_NO_REGEXP_OPTIM str = ch; leftStr = ch; rightStr = ch; maxl = 1; occ1.detach(); occ1[BadChar(ch)] = 0; #endif minl = 1; } void QRegExpEngine::Box::set( const CharClass& cc ) { ls.resize( 1 ); ls[0] = eng->createState( cc ); rs = ls; rs.detach(); #ifndef QT_NO_REGEXP_OPTIM maxl = 1; occ1 = cc.firstOccurrence(); #endif minl = 1; } #ifndef QT_NO_REGEXP_BACKREF void QRegExpEngine::Box::set( int bref ) { ls.resize( 1 ); ls[0] = eng->createState( bref ); rs = ls; rs.detach(); if ( bref >= 1 && bref <= MaxBackRefs ) skipanchors = Anchor_BackRef0Empty << bref; #ifndef QT_NO_REGEXP_OPTIM maxl = InftyLen; #endif minl = 0; } #endif void QRegExpEngine::Box::cat( const Box& b ) { eng->addCatTransitions( rs, b.ls ); addAnchorsToEngine( b ); if ( minl == 0 ) { mergeInto( &lanchors, b.lanchors ); if ( skipanchors != 0 ) { for ( int i = 0; i < (int) b.ls.size(); i++ ) { int a = eng->anchorConcatenation( at(lanchors, b.ls[i]), skipanchors ); lanchors.insert( b.ls[i], a ); } } mergeInto( &ls, b.ls ); } if ( b.minl == 0 ) { mergeInto( &ranchors, b.ranchors ); if ( b.skipanchors != 0 ) { for ( int i = 0; i < (int) rs.size(); i++ ) { int a = eng->anchorConcatenation( at(ranchors, rs[i]), b.skipanchors ); ranchors.insert( rs[i], a ); } } mergeInto( &rs, b.rs ); } else { ranchors = b.ranchors; rs = b.rs; } #ifndef QT_NO_REGEXP_OPTIM if ( maxl != InftyLen ) { if ( rightStr.length() + b.leftStr.length() > QMAX(str.length(), b.str.length()) ) { earlyStart = minl - rightStr.length(); lateStart = maxl - rightStr.length(); str = rightStr + b.leftStr; } else if ( b.str.length() > str.length() ) { earlyStart = minl + b.earlyStart; lateStart = maxl + b.lateStart; str = b.str; } } if ( (int) leftStr.length() == maxl ) leftStr += b.leftStr; if ( (int) b.rightStr.length() == b.maxl ) rightStr += b.rightStr; else rightStr = b.rightStr; if ( maxl == InftyLen || b.maxl == InftyLen ) maxl = InftyLen; else maxl += b.maxl; occ1.detach(); for ( int i = 0; i < NumBadChars; i++ ) { if ( b.occ1[i] != NoOccurrence && minl + b.occ1[i] < occ1[i] ) occ1[i] = minl + b.occ1[i]; } #endif minl += b.minl; if ( minl == 0 ) skipanchors = eng->anchorConcatenation( skipanchors, b.skipanchors ); else skipanchors = 0; } void QRegExpEngine::Box::orx( const Box& b ) { mergeInto( &ls, b.ls ); mergeInto( &lanchors, b.lanchors ); mergeInto( &rs, b.rs ); mergeInto( &ranchors, b.ranchors ); skipanchors = eng->anchorAlternation( skipanchors, b.skipanchors ); #ifndef QT_NO_REGEXP_OPTIM occ1.detach(); for ( int i = 0; i < NumBadChars; i++ ) { if ( occ1[i] > b.occ1[i] ) occ1[i] = b.occ1[i]; } earlyStart = 0; lateStart = 0; str = QString::null; leftStr = QString::null; rightStr = QString::null; if ( b.maxl > maxl ) maxl = b.maxl; #endif if ( b.minl < minl ) minl = b.minl; } void QRegExpEngine::Box::plus( int atom ) { #ifndef QT_NO_REGEXP_CAPTURE eng->addPlusTransitions( rs, ls, atom ); #else Q_UNUSED( atom ); eng->addCatTransitions( rs, ls ); #endif addAnchorsToEngine( *this ); #ifndef QT_NO_REGEXP_OPTIM maxl = InftyLen; #endif } void QRegExpEngine::Box::opt() { #ifndef QT_NO_REGEXP_OPTIM earlyStart = 0; lateStart = 0; str = QString::null; leftStr = QString::null; rightStr = QString::null; #endif skipanchors = 0; minl = 0; } void QRegExpEngine::Box::catAnchor( int a ) { if ( a != 0 ) { for ( int i = 0; i < (int) rs.size(); i++ ) { a = eng->anchorConcatenation( at(ranchors, rs[i]), a ); ranchors.insert( rs[i], a ); } if ( minl == 0 ) skipanchors = eng->anchorConcatenation( skipanchors, a ); } } #ifndef QT_NO_REGEXP_OPTIM void QRegExpEngine::Box::setupHeuristics() { eng->setupGoodStringHeuristic( earlyStart, lateStart, str ); /* A regular expression such as 112|1 has occ1['2'] = 2 and minl = 1 at this point. An entry of occ1 has to be at most minl or infinity for the rest of the algorithm to go well. We waited until here before normalizing these cases (instead of doing it in Box::orx()) because sometimes things improve by themselves; consider (112|1)34. */ for ( int i = 0; i < NumBadChars; i++ ) { if ( occ1[i] != NoOccurrence && occ1[i] >= minl ) occ1[i] = minl; } eng->setupBadCharHeuristic( minl, occ1 ); eng->heuristicallyChooseHeuristic(); } #endif #if defined(QT_DEBUG) void QRegExpEngine::Box::dump() const { int i; qDebug( "Box of at least %d character%s", minl, minl == 1 ? "" : "s" ); qDebug( " Left states:" ); for ( i = 0; i < (int) ls.size(); i++ ) { if ( at(lanchors, ls[i]) == 0 ) qDebug( " %d", ls[i] ); else qDebug( " %d [anchors 0x%.8x]", ls[i], lanchors[ls[i]] ); } qDebug( " Right states:" ); for ( i = 0; i < (int) rs.size(); i++ ) { if ( at(ranchors, ls[i]) == 0 ) qDebug( " %d", rs[i] ); else qDebug( " %d [anchors 0x%.8x]", rs[i], ranchors[rs[i]] ); } qDebug( " Skip anchors: 0x%.8x", skipanchors ); } #endif void QRegExpEngine::Box::addAnchorsToEngine( const Box& to ) const { for ( int i = 0; i < (int) to.ls.size(); i++ ) { for ( int j = 0; j < (int) rs.size(); j++ ) { int a = eng->anchorConcatenation( at(ranchors, rs[j]), at(to.lanchors, to.ls[i]) ); eng->addAnchors( rs[j], to.ls[i], a ); } } } int QRegExpEngine::getChar() { return ( yyPos == yyLen ) ? EOS : yyIn[yyPos++].unicode(); } int QRegExpEngine::getEscape() { #ifndef QT_NO_REGEXP_ESCAPE const char tab[] = "afnrtv"; // no b, as \b means word boundary const char backTab[] = "\a\f\n\r\t\v"; ushort low; int i; #endif ushort val; int prevCh = yyCh; if ( prevCh == EOS ) { yyError = TRUE; return Tok_Char | '\\'; } yyCh = getChar(); #ifndef QT_NO_REGEXP_ESCAPE if ( (prevCh & ~0xff) == 0 ) { const char *p = strchr( tab, prevCh ); if ( p != 0 ) return Tok_Char | backTab[p - tab]; } #endif switch ( prevCh ) { #ifndef QT_NO_REGEXP_ESCAPE case '0': val = 0; for ( i = 0; i < 3; i++ ) { if ( yyCh >= '0' && yyCh <= '7' ) val = ( val << 3 ) | ( yyCh - '0' ); else break; yyCh = getChar(); } if ( (val & ~0377) != 0 ) yyError = TRUE; return Tok_Char | val; #endif #ifndef QT_NO_REGEXP_ESCAPE case 'B': return Tok_NonWord; #endif #ifndef QT_NO_REGEXP_CCLASS case 'D': // see QChar::isDigit() yyCharClass->addCategories( 0x7fffffef ); return Tok_CharClass; case 'S': // see QChar::isSpace() yyCharClass->addCategories( 0x7ffff87f ); yyCharClass->addRange( 0x0000, 0x0008 ); yyCharClass->addRange( 0x000e, 0x001f ); yyCharClass->addRange( 0x007f, 0x009f ); return Tok_CharClass; case 'W': // see QChar::isLetterOrNumber() yyCharClass->addCategories( 0x7ff07f8f ); return Tok_CharClass; #endif #ifndef QT_NO_REGEXP_ESCAPE case 'b': return Tok_Word; #endif #ifndef QT_NO_REGEXP_CCLASS case 'd': // see QChar::isDigit() yyCharClass->addCategories( 0x00000010 ); return Tok_CharClass; case 's': // see QChar::isSpace() yyCharClass->addCategories( 0x00000380 ); yyCharClass->addRange( 0x0009, 0x000d ); return Tok_CharClass; case 'w': // see QChar::isLetterOrNumber() yyCharClass->addCategories( 0x000f8070 ); return Tok_CharClass; #endif #ifndef QT_NO_REGEXP_ESCAPE case 'x': val = 0; for ( i = 0; i < 4; i++ ) { low = QChar( yyCh ).lower(); if ( low >= '0' && low <= '9' ) val = ( val << 4 ) | ( low - '0' ); else if ( low >= 'a' && low <= 'f' ) val = ( val << 4 ) | ( low - 'a' + 10 ); else break; yyCh = getChar(); } return Tok_Char | val; #endif default: if ( prevCh >= '1' && prevCh <= '9' ) { #ifndef QT_NO_REGEXP_BACKREF val = prevCh - '0'; while ( yyCh >= '0' && yyCh <= '9' ) { val = ( val *= 10 ) | ( yyCh - '0' ); yyCh = getChar(); } return Tok_BackRef | val; #else yyError = TRUE; #endif } return Tok_Char | prevCh; } } #ifndef QT_NO_REGEXP_INTERVAL int QRegExpEngine::getRep( int def ) { if ( yyCh >= '0' && yyCh <= '9' ) { int rep = 0; do { rep = 10 * rep + yyCh - '0'; if ( rep >= InftyRep ) { yyError = TRUE; rep = def; } yyCh = getChar(); } while ( yyCh >= '0' && yyCh <= '9' ); return rep; } else { return def; } } #endif #ifndef QT_NO_REGEXP_LOOKAHEAD void QRegExpEngine::skipChars( int n ) { if ( n > 0 ) { yyPos += n - 1; yyCh = getChar(); } } #endif void QRegExpEngine::startTokenizer( const QChar *rx, int len ) { yyIn = rx; yyPos0 = 0; yyPos = 0; yyLen = len; yyCh = getChar(); yyCharClass = new CharClass; yyMinRep = 0; yyMaxRep = 0; yyError = FALSE; } int QRegExpEngine::getToken() { #ifndef QT_NO_REGEXP_CCLASS ushort pendingCh = 0; bool charPending; bool rangePending; int tok; #endif int prevCh = yyCh; yyPos0 = yyPos - 1; #ifndef QT_NO_REGEXP_CCLASS yyCharClass->clear(); #endif yyMinRep = 0; yyMaxRep = 0; yyCh = getChar(); switch ( prevCh ) { case EOS: yyPos0 = yyPos; return Tok_Eos; case '$': return Tok_Dollar; case '(': if ( yyCh == '?' ) { prevCh = getChar(); yyCh = getChar(); switch ( prevCh ) { #ifndef QT_NO_REGEXP_LOOKAHEAD case '!': return Tok_NegLookahead; case '=': return Tok_PosLookahead; #endif case ':': return Tok_MagicLeftParen; default: yyError = TRUE; return Tok_MagicLeftParen; } } else { return Tok_LeftParen; } case ')': return Tok_RightParen; case '*': yyMinRep = 0; yyMaxRep = InftyRep; return Tok_Quantifier; case '+': yyMinRep = 1; yyMaxRep = InftyRep; return Tok_Quantifier; case '.': #ifndef QT_NO_REGEXP_CCLASS yyCharClass->setNegative( TRUE ); #endif return Tok_CharClass; case '?': yyMinRep = 0; yyMaxRep = 1; return Tok_Quantifier; case '[': #ifndef QT_NO_REGEXP_CCLASS if ( yyCh == '^' ) { yyCharClass->setNegative( TRUE ); yyCh = getChar(); } charPending = FALSE; rangePending = FALSE; do { if ( yyCh == '-' && charPending && !rangePending ) { rangePending = TRUE; yyCh = getChar(); } else { if ( charPending && !rangePending ) { yyCharClass->addSingleton( pendingCh ); charPending = FALSE; } if ( yyCh == '\\' ) { yyCh = getChar(); tok = getEscape(); if ( tok == Tok_Word ) tok = '\b'; } else { tok = Tok_Char | yyCh; yyCh = getChar(); } if ( tok == Tok_CharClass ) { if ( rangePending ) { yyCharClass->addSingleton( '-' ); yyCharClass->addSingleton( pendingCh ); charPending = FALSE; rangePending = FALSE; } } else if ( (tok & Tok_Char) != 0 ) { if ( rangePending ) { yyCharClass->addRange( pendingCh, tok ^ Tok_Char ); charPending = FALSE; rangePending = FALSE; } else { pendingCh = tok ^ Tok_Char; charPending = TRUE; } } else { yyError = TRUE; } } } while ( yyCh != ']' && yyCh != EOS ); if ( rangePending ) yyCharClass->addSingleton( '-' ); if ( charPending ) yyCharClass->addSingleton( pendingCh ); if ( yyCh == EOS ) yyError = TRUE; else yyCh = getChar(); return Tok_CharClass; #else yyError = TRUE; return Tok_Char | '['; #endif case '\\': return getEscape(); case ']': yyError = TRUE; return Tok_Char | ']'; case '^': return Tok_Caret; #ifndef QT_NO_REGEXP_INTERVAL case '{': yyMinRep = getRep( 0 ); yyMaxRep = yyMinRep; if ( yyCh == ',' ) { yyCh = getChar(); yyMaxRep = getRep( InftyRep ); } if ( yyMaxRep < yyMinRep ) qSwap( yyMinRep, yyMaxRep ); if ( yyCh != '}' ) yyError = TRUE; yyCh = getChar(); return Tok_Quantifier; #else yyError = TRUE; return Tok_Char | '{'; #endif case '|': return Tok_Bar; case '}': yyError = TRUE; return Tok_Char | '}'; default: return Tok_Char | prevCh; } } int QRegExpEngine::parse( const QChar *pattern, int len ) { valid = TRUE; startTokenizer( pattern, len ); yyTok = getToken(); #ifndef QT_NO_REGEXP_CAPTURE yyMayCapture = TRUE; #else yyMayCapture = FALSE; #endif #ifndef QT_NO_REGEXP_CAPTURE int atom = startAtom( FALSE ); #endif CharClass anything; Box box( this ); // create InitialState box.set( anything ); Box rightBox( this ); // create FinalState rightBox.set( anything ); Box middleBox( this ); parseExpression( &middleBox ); #ifndef QT_NO_REGEXP_CAPTURE finishAtom( atom ); #endif #ifndef QT_NO_REGEXP_OPTIM middleBox.setupHeuristics(); #endif box.cat( middleBox ); box.cat( rightBox ); delete yyCharClass; yyCharClass = 0; realncap = ncap; #ifndef QT_NO_REGEXP_BACKREF if ( nbrefs > ncap ) ncap = nbrefs; #endif mmCaptured.resize( 2 + 2 * realncap ); mmCapturedNoMatch.fill( -1, 2 + 2 * realncap ); /* We use one QArray for all the big data used a lot in matchHere() and friends. */ #ifndef QT_NO_REGEXP_OPTIM mmSlideTabSize = QMAX( minl + 1, 16 ); #else mmSlideTabSize = 0; #endif mmBigArray.resize( (3 + 4 * ncap) * ns + 4 * ncap + mmSlideTabSize ); mmInNextStack = mmBigArray.data(); memset( mmInNextStack, -1, ns * sizeof(int) ); mmCurStack = mmInNextStack + ns; mmNextStack = mmInNextStack + 2 * ns; mmCurCapBegin = mmInNextStack + 3 * ns; mmNextCapBegin = mmCurCapBegin + ncap * ns; mmCurCapEnd = mmCurCapBegin + 2 * ncap * ns; mmNextCapEnd = mmCurCapBegin + 3 * ncap * ns; mmTempCapBegin = mmCurCapBegin + 4 * ncap * ns; mmTempCapEnd = mmTempCapBegin + ncap; mmCapBegin = mmTempCapBegin + 2 * ncap; mmCapEnd = mmTempCapBegin + 3 * ncap; mmSlideTab = mmTempCapBegin + 4 * ncap; if ( yyError ) return -1; #ifndef QT_NO_REGEXP_OPTIM State *sinit = s[InitialState]; caretAnchored = ( sinit->anchors != 0 ); if ( caretAnchored ) { QMap& anchors = *sinit->anchors; QMap::ConstIterator a; for ( a = anchors.begin(); a != anchors.end(); ++a ) { #ifndef QT_NO_REGEXP_ANCHOR_ALT if ( (*a & Anchor_Alternation) != 0 ) break; #endif if ( (*a & Anchor_Caret) == 0 ) { caretAnchored = FALSE; break; } } } #endif return yyPos0; } void QRegExpEngine::parseAtom( Box *box ) { #ifndef QT_NO_REGEXP_LOOKAHEAD QRegExpEngine *eng = 0; bool neg; int len; #endif switch ( yyTok ) { case Tok_Dollar: box->catAnchor( Anchor_Dollar ); break; case Tok_Caret: box->catAnchor( Anchor_Caret ); break; #ifndef QT_NO_REGEXP_LOOKAHEAD case Tok_PosLookahead: case Tok_NegLookahead: neg = ( yyTok == Tok_NegLookahead ); eng = new QRegExpEngine( cs ); len = eng->parse( yyIn + yyPos - 1, yyLen - yyPos + 1 ); if ( len >= 0 ) skipChars( len ); else yyError = TRUE; box->catAnchor( addLookahead(eng, neg) ); yyTok = getToken(); if ( yyTok != Tok_RightParen ) yyError = TRUE; break; #endif #ifndef QT_NO_REGEXP_ESCAPE case Tok_Word: box->catAnchor( Anchor_Word ); break; case Tok_NonWord: box->catAnchor( Anchor_NonWord ); break; #endif case Tok_LeftParen: case Tok_MagicLeftParen: yyTok = getToken(); parseExpression( box ); if ( yyTok != Tok_RightParen ) yyError = TRUE; break; case Tok_CharClass: box->set( *yyCharClass ); break; default: if ( (yyTok & Tok_Char) != 0 ) box->set( QChar(yyTok ^ Tok_Char) ); #ifndef QT_NO_REGEXP_BACKREF else if ( (yyTok & Tok_BackRef) != 0 ) box->set( yyTok ^ Tok_BackRef ); #endif else yyError = TRUE; } yyTok = getToken(); } void QRegExpEngine::parseFactor( Box *box ) { #ifndef QT_NO_REGEXP_CAPTURE int atom = startAtom( yyMayCapture && yyTok == Tok_LeftParen ); #else static const int atom = 0; #endif #ifndef QT_NO_REGEXP_INTERVAL #define YYREDO() \ yyIn = in, yyPos0 = pos0, yyPos = pos, yyLen = len, yyCh = ch, \ *yyCharClass = charClass, yyMinRep = 0, yyMaxRep = 0, yyTok = tok const QChar *in = yyIn; int pos0 = yyPos0; int pos = yyPos; int len = yyLen; int ch = yyCh; CharClass charClass; if ( yyTok == Tok_CharClass ) charClass = *yyCharClass; int tok = yyTok; bool mayCapture = yyMayCapture; #endif parseAtom( box ); #ifndef QT_NO_REGEXP_CAPTURE finishAtom( atom ); #endif if ( yyTok == Tok_Quantifier ) { if ( yyMaxRep == InftyRep ) { box->plus( atom ); #ifndef QT_NO_REGEXP_INTERVAL } else if ( yyMaxRep == 0 ) { box->clear(); #endif } if ( yyMinRep == 0 ) box->opt(); #ifndef QT_NO_REGEXP_INTERVAL yyMayCapture = FALSE; int alpha = ( yyMinRep == 0 ) ? 0 : yyMinRep - 1; int beta = ( yyMaxRep == InftyRep ) ? 0 : yyMaxRep - ( alpha + 1 ); Box rightBox( this ); int i; for ( i = 0; i < beta; i++ ) { YYREDO(); Box leftBox( this ); parseAtom( &leftBox ); leftBox.cat( rightBox ); leftBox.opt(); rightBox = leftBox; } for ( i = 0; i < alpha; i++ ) { YYREDO(); Box leftBox( this ); parseAtom( &leftBox ); leftBox.cat( rightBox ); rightBox = leftBox; } rightBox.cat( *box ); *box = rightBox; #endif yyTok = getToken(); #ifndef QT_NO_REGEXP_INTERVAL yyMayCapture = mayCapture; #endif } #undef YYREDO } void QRegExpEngine::parseTerm( Box *box ) { #ifndef QT_NO_REGEXP_OPTIM if ( yyTok != Tok_Eos && yyTok != Tok_RightParen && yyTok != Tok_Bar ) parseFactor( box ); #endif while ( yyTok != Tok_Eos && yyTok != Tok_RightParen && yyTok != Tok_Bar ) { Box rightBox( this ); parseFactor( &rightBox ); box->cat( rightBox ); } } void QRegExpEngine::parseExpression( Box *box ) { parseTerm( box ); while ( yyTok == Tok_Bar ) { Box rightBox( this ); yyTok = getToken(); parseTerm( &rightBox ); box->orx( rightBox ); } } /* The class QRegExpPrivate contains the private data of a regular expression other than the automaton. It makes it possible for many QRegExp objects to use the same QRegExpEngine object with different QRegExpPrivate objects. */ struct QRegExpPrivate { QString pattern; // regular-expression or wildcard pattern QString rxpattern; // regular-expression pattern #ifndef QT_NO_REGEXP_WILDCARD bool wc; // wildcard mode? #endif bool min; // minimal matching? (instead of maximal) #ifndef QT_NO_REGEXP_CAPTURE QString t; // last string passed to QRegExp::search() or searchRev() QStringList capturedCache; // what QRegExp::capturedTexts() returned last #endif QArray captured; // what QRegExpEngine::search() returned last QRegExpPrivate() { captured.fill( -1, 2 ); } }; #ifndef QT_NO_REGEXP_OPTIM static QCache *engineCache = 0; #endif static QRegExpEngine *newEngine( const QString& pattern, bool caseSensitive ) { #ifndef QT_NO_REGEXP_OPTIM if ( engineCache != 0 ) { QRegExpEngine *eng = engineCache->take( pattern ); if ( eng == 0 || eng->caseSensitive() != caseSensitive ) { delete eng; } else { eng->ref(); return eng; } } #endif return new QRegExpEngine( pattern, caseSensitive ); } static void derefEngine( QRegExpEngine *eng, const QString& pattern ) { if ( eng != 0 && eng->deref() ) { #ifndef QT_NO_REGEXP_OPTIM if ( engineCache == 0 ) { engineCache = new QCache; engineCache->setAutoDelete( TRUE ); } if ( !pattern.isNull() && engineCache->insert(pattern, eng, 4 + pattern.length() / 4) ) return; #else Q_UNUSED( pattern ); #endif delete eng; } } /*! Constructs an empty regexp. \sa isValid() */ QRegExp3::QRegExp3() { eng = new QRegExpEngine( TRUE ); priv = new QRegExpPrivate; priv->pattern = QString::null; #ifndef QT_NO_REGEXP_WILDCARD priv->wc = FALSE; #endif priv->min = FALSE; compile( TRUE ); } /*! Constructs a regular expression object for the given \a pattern string. The pattern must be given using wildcard notation if \a wildcard is TRUE (default is FALSE). The pattern is case sensitive, unless \a caseSensitive is FALSE. Matching is greedy (maximal), but can be changed by calling setMinimal(). \sa setPattern() setCaseSensitive() setWildcard() setMinimal() */ QRegExp3::QRegExp3( const QString& pattern, bool caseSensitive, bool wildcard ) { eng = 0; priv = new QRegExpPrivate; priv->pattern = pattern; #ifndef QT_NO_REGEXP_WILDCARD priv->wc = wildcard; #endif priv->min = FALSE; compile( caseSensitive ); } /*! Constructs a regular expression as a copy of \a rx. \sa operator=() */ QRegExp3::QRegExp3( const QRegExp3& rx ) { eng = 0; priv = new QRegExpPrivate; operator=( rx ); } /*! Destroys the regular expression and cleans up its internal data. */ QRegExp3::~QRegExp3() { derefEngine( eng, priv->rxpattern ); delete priv; } /*! Copies the regular expression \a rx and returns a reference to the copy. The case sensitivity, wildcard and minimal matching options are copied as well. */ QRegExp3& QRegExp3::operator=( const QRegExp3& rx ) { rx.eng->ref(); derefEngine( eng, priv->rxpattern ); eng = rx.eng; priv->pattern = rx.priv->pattern; priv->rxpattern = rx.priv->rxpattern; #ifndef QT_NO_REGEXP_WILDCARD priv->wc = rx.priv->wc; #endif priv->min = rx.priv->min; #ifndef QT_NO_REGEXP_CAPTURE priv->t = rx.priv->t; priv->capturedCache = rx.priv->capturedCache; #endif priv->captured = rx.priv->captured; return *this; } /*! Returns TRUE if this regular expression is equal to \a rx, otherwise returns FALSE. Two QRegExp3 objects are equal if they have the same pattern strings and the same settings for case sensitivity, wildcard and minimal matching. */ bool QRegExp3::operator==( const QRegExp3& rx ) const { return priv->pattern == rx.priv->pattern && eng->caseSensitive() == rx.eng->caseSensitive() && #ifndef QT_NO_REGEXP_WILDCARD priv->wc == rx.priv->wc && #endif priv->min == rx.priv->min; } /*! \fn bool QRegExp3::operator!=( const QRegExp& rx ) const Returns TRUE if this regular expression is not equal to \a rx, otherwise FALSE. \sa operator==() */ /*! Returns TRUE if the pattern string is empty, otherwise FALSE. If you call match() with an empty pattern on an empty string it will return TRUE otherwise it returns FALSE since match() operates over the whole string. If you call search() with an empty pattern on \e any string it will return the start position (0 by default) since it will match at the start position, because the empty pattern matches the 'emptiness' at the start of the string, and the length of the match returned by matchedLength() will be 0. See QString::isEmpty(). */ bool QRegExp3::isEmpty() const { return priv->pattern.isEmpty(); } /*! Returns TRUE if the regular expression is valid, or FALSE if it's invalid. An invalid regular expression never matches. The pattern [a-z is an example of an invalid pattern, since it lacks a closing square bracket. Note that the validity of a regexp may also depend on the setting of the wildcard flag, for example *.html is a valid wildcard regexp but an invalid full regexp. */ bool QRegExp3::isValid() const { return eng->isValid(); } /*! Returns the pattern string of the regular expression. The pattern has either regular expression syntax or wildcard syntax, depending on wildcard(). \sa setPattern() */ QString QRegExp3::pattern() const { return priv->pattern; } /*! Sets the pattern string to \a pattern and returns a reference to this regular expression. The case sensitivity, wildcard and minimal matching options are not changed. \sa pattern() */ void QRegExp3::setPattern( const QString& pattern ) { if ( priv->pattern != pattern ) { priv->pattern = pattern; compile( caseSensitive() ); } } /*! Returns TRUE if case sensitivity is enabled, otherwise FALSE. The default is TRUE. \sa setCaseSensitive() */ bool QRegExp3::caseSensitive() const { return eng->caseSensitive(); } /*! Sets case sensitive matching to \a sensitive. If \a sensitive is TRUE, \\.txt$ matches readme.txt but not README.TXT. \sa caseSensitive() */ void QRegExp3::setCaseSensitive( bool sensitive ) { if ( sensitive != eng->caseSensitive() ) compile( sensitive ); } #ifndef QT_NO_REGEXP_WILDCARD /*! Returns TRUE if wildcard mode is enabled, otherwise FALSE. The default is FALSE. \sa setWildcard() */ bool QRegExp3::wildcard() const { return priv->wc; } /*! Sets the wildcard mode for the regular expression. The default is FALSE. Setting \a wildcard to TRUE enables simple shell-like wildcard matching. (See wildcard matching (globbing).) For example, r*.txt matches the string readme.txt in wildcard mode, but does not match readme. \sa wildcard() */ void QRegExp3::setWildcard( bool wildcard ) { if ( wildcard != priv->wc ) { priv->wc = wildcard; compile( caseSensitive() ); } } #endif /*! Returns TRUE if minimal (non-greedy) matching is enabled, otherwise returns FALSE. \sa setMinimal() */ bool QRegExp3::minimal() const { return priv->min; } /*! Enables or disables minimal matching. If \a minimal is FALSE, matching is greedy (maximal) which is the default. For example, suppose we have the input string "We must be \bold\, very \bold\!" and the pattern \.*\. With the default greedy (maximal) matching, the match is "We must be \bold\, very \bold\!". But with minimal (non-greedy) matching the first match is: "We must be \bold\, very \bold\!" and the second match is "We must be \bold\, very \bold\!". In practice we might use the pattern \[^\<]+\, although this will still fail for nested tags. \sa minimal() */ void QRegExp3::setMinimal( bool minimal ) { priv->min = minimal; } /*! Returns TRUE if \a str is matched exactly by this regular expression otherwise it returns FALSE. You can determine how much of the string was matched by calling matchedLength(). For a given regexp string, R, match("R") is the equivalent of search("^R$") since match() effectively encloses the regexp in the start of string and end of string anchors. For example, if the regular expression is blue, then match() returns TRUE only for input blue. For inputs bluebell, blutak and lightblue, match() returns FALSE and matchedLength() will return 4, 3 and 0 respectively. \sa search() searchRev() QRegExpValidator */ bool QRegExp3::exactMatch( const QString& str ) { #ifndef QT_NO_REGEXP_CAPTURE priv->t = str; priv->capturedCache.clear(); #endif priv->captured = eng->match( str, 0, priv->min, TRUE ); if ( priv->captured[1] == (int) str.length() ) { return TRUE; } else { priv->captured.detach(); priv->captured[0] = 0; priv->captured[1] = eng->matchedLength(); return FALSE; } } /*! \overload This version does not set matchedLength(), capturedTexts() and friends. */ bool QRegExp3::exactMatch( const QString& str ) const { return eng->match(str, 0, priv->min, TRUE)[0] == 0 && eng->matchedLength() == (int) str.length(); } /*! \obsolete Attempts to match in \a str, starting from position \a index. Returns the position of the match, or -1 if there was no match. The length of the match is stored in \a *len, unless \a len is a null pointer. If \a indexIsStart is TRUE (the default), the position \a index in the string will match the start of string anchor, ^, in the regexp, if present. Otherwise, position 0 in \a str will match. Use search() and matchedLength() instead of this function. If you really need the \a indexIsStart functionality, try this: \code QRegExp3 rx( "some pattern" ); int pos = rx.search( str.mid( index ) ); if ( pos != -1 ) pos += index; int len = rx.matchedLength(); \endcode */ #ifndef QT_NO_COMPAT int QRegExp3::match( const QString& str, int index, int *len, bool indexIsStart ) { int pos; if ( indexIsStart ) { pos = search( str.mid(index) ); if ( pos >= 0 ) { pos += index; if ( len != 0 ) *len = matchedLength(); } else { if ( len != 0 ) *len = 0; } } else { pos = search( str, index ); if ( len != 0 ) *len = matchedLength(); } return pos; } #endif /*! Attempts to find a match in \a str from position \a start (0 by default). If \a start is -1, the search starts at the last character; if -2, at the next to last character; etc. Returns the position of the first match, or -1 if there was no match. You might prefer to use QString::find(), QString::contains() or even QStringList::grep(). To replace matches use QString::replace(). Example: \code QString str = "offsets: 1.23 .50 71.00 6.00"; QRegExp3 rx( "\\d*\\.\\d+" ); // very simple floating point matching int count = 0; int pos = 0; while ( pos >= 0 ) { pos = rx.search( str, pos ); count++; } // pos will be 9, 14, 18 and finally 24; count will end up as 4. \endcode \sa searchRev() match() matchedLength() capturedTexts() */ // QChar versions #ifdef QCHAR_SUPPORT const QString makeString(const QChar *str) { // A sentinel value checked in case the QChar *ptr is never null terminated const uint MAXLENGTH=65535; const QChar *s=str; uint i=0; while(i < MAXLENGTH && *s != QChar::null) { i++;s++ ;} return QString(str,i); } int QRegExp3::search(const QChar *str,int start) { return search(makeString(str),start); } int QRegExp3::search(const QChar *str,int start) const { return search(makeString(str),start); } int QRegExp3::searchRev(const QChar *str,int start) { return searchRev(makeString(str),start); } int QRegExp3::searchRev(const QChar *str,int start) const { return searchRev(makeString(str),start); } bool QRegExp3::exactMatch(const QChar *str) { return exactMatch(makeString(str)); } bool QRegExp3::exactMatch(const QChar *str) const { return exactMatch(makeString(str)); } #endif // QCHAR_SUPPORT int QRegExp3::search( const QString& str, int start ) { if ( start < 0 ) start += str.length(); #ifndef QT_NO_REGEXP_CAPTURE priv->t = str; priv->capturedCache.clear(); #endif priv->captured = eng->match( str, start, priv->min, FALSE ); return priv->captured[0]; } /*! \overload This version does not set matchedLength(), capturedTexts() and friends. */ int QRegExp3::search( const QString& str, int start ) const { if ( start < 0 ) start += str.length(); return eng->match( str, start, priv->min, FALSE )[0]; } /*! Attempts to find a match backwards in \a str from position \a start. If \a start is -1 (the default), the search starts at the last character; if -2, at the next to last character; etc. Returns the position of the first match, or -1 if there was no match. You might prefer to use QString::findRev(). \sa search() matchedLength() capturedTexts() */ int QRegExp3::searchRev( const QString& str, int start ) { if ( start < 0 ) start += str.length(); #ifndef QT_NO_REGEXP_CAPTURE priv->t = str; priv->capturedCache.clear(); #endif if ( start < 0 || start > (int) str.length() ) { priv->captured.detach(); priv->captured.fill( -1 ); return -1; } while ( start >= 0 ) { priv->captured = eng->match( str, start, priv->min, TRUE ); if ( priv->captured[0] == start ) return start; start--; } return -1; } /*! \overload This version does not set matchedLength(), capturedText() and friends. */ int QRegExp3::searchRev( const QString& str, int start ) const { if ( start < 0 ) start += str.length(); if ( start < 0 || start > (int) str.length() ) return -1; while ( start >= 0 ) { if ( eng->match(str, start, priv->min, TRUE)[0] == start ) return start; start--; } return -1; } /*! Returns the length of the last matched string, or -1 if there was no match. \sa match() search() */ int QRegExp3::matchedLength() { return priv->captured[1]; } #ifndef QT_NO_REGEXP_CAPTURE /*! Returns a list of the captured text strings. The first string in the list is the entire matched string. Each subsequent list element contains a string that matched a (capturing) subexpression of the regexp. For example: \code QRegExp3 rx( "(\\d+)(\\s*)(cm|inch(es)?)" ); int pos = rx.search( "Length: 36 inches" ); QStringList list = rx.capturedTexts(); // list is now ( "36 inches", "36", " ", "inches", "es" ). \endcode The above example also captures elements that may be present but which we have no interest in. This problem can be solved by using non-capturing parenthesis: \code QRegExp3 rx( "(\\d+)(?:\\s*)(cm|inch(?:es)?)" ); int pos = rx.search( "Length: 36 inches" ); QStringList list = rx.capturedTexts(); // list is now ( "36 inches", "36", "inches" ). \endcode Some regexps can match an indeterminate number of times. For example if the input string is "Offsets: 12 14 99 231 7" and the regexp, rx, is (\\d+)+, we would hope to get a list of all the numbers matched. However, after calling rx.search(str), capturedTexts() will return the list ( "12", "12" ), i.e. the entire match was "12" and the first subexpression matched was "12". The correct approach is to use cap() in a loop. The order of elements in the string list is as follows. The first element is the entire matching string. Each subsequent element corresponds to the next capturing open left parenthesis. Thus capturedTexts()[1] is the text of the first capturing parenthesis, capturedTexts()[2] is the text of the second and so on (corresponding to $1, $2 etc. in some other regexp languages). \sa cap() pos() */ QStringList QRegExp3::capturedTexts() { if ( priv->capturedCache.isEmpty() ) { for ( int i = 0; i < (int) priv->captured.size(); i += 2 ) { QString m; if ( priv->captured[i + 1] == 0 ) m = QString::fromLatin1( "" ); else if ( priv->captured[i] >= 0 ) m = priv->t.mid( priv->captured[i], priv->captured[i + 1] ); priv->capturedCache.append( m ); } priv->t = QString::null; } return priv->capturedCache; } /*! Returns the text captured by the \a nth subexpression. The entire match has index 0 and the parenthesised subexpressions have indices starting from 1 (excluding non-capturing parenthesis). \code QRegExp3 rxlen( "(\\d+)(?:\\s*)(cm|inch)" ); int pos = rxlen.search( "Length: 189cm" ); if ( pos > -1 ) { QString value = rxlen.cap( 1 ); // "189" QString unit = rxlen.cap( 2 ); // "cm" // ... } \endcode Some patterns may lead to a number of matches which cannot be determined in advance, for example: \code QRegExp3 rx( "(\\d+)" ); str = "Offsets: 12 14 99 231 7"; QStringList list; pos = 0; while ( pos >= 0 ) { pos = rx.search( str, pos ); if ( pos > -1 ) { list += rx.cap( 1 ); pos += rx.matchedLength(); } } // list contains: ( "12", "14", "99", "231", "7" ). \endcode The order of elements matched by cap() is as follows. The first element, cap( 0 ), is the entire matching string. Each subsequent element corresponds to the next capturing open left parenthesis. Thus cap( 1 ) is the text of the first capturing parenthesis, cap( 2 ) is the text of the second and so on. \sa search() pos() capturedTexts() */ QString QRegExp3::cap( int nth ) { if ( nth < 0 || nth >= (int) priv->captured.size() / 2 ) return QString::null; else return capturedTexts()[nth]; } /*! Returns the position of the \a nth captured text in the searched string. If \a nth is 0 (the default), pos() returns the position of the whole match. Example: \code QRegExp3 rx( "/([a-z]+)/([a-z]+)" ); rx.search( "Output /dev/null" ); // Returns 7 (position of /dev/null) rx.pos( 0 ); // Returns 7 (position of /dev/null) rx.pos( 1 ); // Returns 8 (position of dev) rx.pos( 2 ); // Returns 12 (position of null) \endcode Note that pos() returns -1 for zero-length matches. (For example, if cap(4) would return an empty string, pos(4) returns -1.) This is due to an implementation tradeoff. \sa capturedTexts() cap() */ int QRegExp3::pos( int nth ) { if ( nth < 0 || nth >= (int) priv->captured.size() / 2 ) return -1; else return priv->captured[2 * nth]; } #endif void QRegExp3::compile( bool caseSensitive ) { derefEngine( eng, priv->rxpattern ); #ifndef QT_NO_REGEXP_WILDCARD if ( priv->wc ) priv->rxpattern = wc2rx( priv->pattern ); else #endif priv->rxpattern = priv->pattern.isNull() ? QString::fromLatin1( "" ) : priv->pattern; eng = newEngine( priv->rxpattern, caseSensitive ); #ifndef QT_NO_REGEXP_CAPTURE priv->t = QString::null; priv->capturedCache.clear(); #endif priv->captured.detach(); priv->captured.fill( -1, 2 + 2 * eng->numCaptures() ); }