source: trunk/yao/share/antlr-2.7.7/lib/cpp/antlr/CharScanner.hpp @ 1

#ifndef INC_CharScanner_hpp__
#define INC_CharScanner_hpp__

/* ANTLR Translator Generator
 * Project led by Terence Parr at http://www.jGuru.com
 * Software rights: http://www.antlr.org/license.html
 *
 * $Id: //depot/code/org.antlr/release/antlr-2.7.7/lib/cpp/antlr/CharScanner.hpp#2 $
 */

#include <antlr/config.hpp>

#include <map>

#ifdef HAS_NOT_CCTYPE_H
#include <ctype.h>
#else
#include <cctype>
#endif

#if ( _MSC_VER == 1200 )
// VC6 seems to need this
// note that this is not a standard C++ include file.
# include <stdio.h>
#endif

#include <antlr/TokenStream.hpp>
#include <antlr/RecognitionException.hpp>
#include <antlr/SemanticException.hpp>
#include <antlr/MismatchedCharException.hpp>
#include <antlr/InputBuffer.hpp>
#include <antlr/BitSet.hpp>
#include <antlr/LexerSharedInputState.hpp>

#ifdef ANTLR_CXX_SUPPORTS_NAMESPACE
namespace antlr {
#endif

class ANTLR_API CharScanner;

ANTLR_C_USING(tolower)

#ifdef ANTLR_REALLY_NO_STRCASECMP
// Apparently, neither strcasecmp nor stricmp is standard, and Codewarrior
// on the mac has neither...
inline int strcasecmp(const char *s1, const char *s2)
{
        while (true)
        {
                char  c1 = tolower(*s1++),
                                c2 = tolower(*s2++);
                if (c1 < c2) return -1;
                if (c1 > c2) return 1;
                if (c1 == 0) return 0;
        }
}
#else
#ifdef NO_STRCASECMP
ANTLR_C_USING(stricmp)
#else
ANTLR_C_USING(strcasecmp)
#endif
#endif

/** Functor for the literals map
 */
class ANTLR_API CharScannerLiteralsLess : public ANTLR_USE_NAMESPACE(std)binary_function<ANTLR_USE_NAMESPACE(std)string,ANTLR_USE_NAMESPACE(std)string,bool> {
private:
        const CharScanner* scanner;
public:
#ifdef NO_TEMPLATE_PARTS
        CharScannerLiteralsLess() {} // not really used, definition to appease MSVC
#endif
        CharScannerLiteralsLess(const CharScanner* theScanner)
        : scanner(theScanner)
        {
        }
        bool operator() (const ANTLR_USE_NAMESPACE(std)string& x,const ANTLR_USE_NAMESPACE(std)string& y) const;
// defaults are good enough..
        //      CharScannerLiteralsLess(const CharScannerLiteralsLess&);
        //      CharScannerLiteralsLess& operator=(const CharScannerLiteralsLess&);
};

/** Superclass of generated lexers
 */
class ANTLR_API CharScanner : public TokenStream {
protected:
        typedef RefToken (*factory_type)();
public:
        CharScanner(InputBuffer& cb, bool case_sensitive );
        CharScanner(InputBuffer* cb, bool case_sensitive );
        CharScanner(const LexerSharedInputState& state, bool case_sensitive );

        virtual ~CharScanner()
        {
        }

        virtual int LA(unsigned int i);

        virtual void append(char c)
        {
                if (saveConsumedInput)
                {
                        size_t l = text.length();

                        if ((l%256) == 0)
                                text.reserve(l+256);

                        text.replace(l,0,&c,1);
                }
        }

        virtual void append(const ANTLR_USE_NAMESPACE(std)string& s)
        {
                if( saveConsumedInput )
                        text += s;
        }

        virtual void commit()
        {
                inputState->getInput().commit();
        }

        /** called by the generated lexer to do error recovery, override to
         * customize the behaviour.
         */
        virtual void recover(const RecognitionException& ex, const BitSet& tokenSet)
        {
                consume();
                consumeUntil(tokenSet);
        }

        virtual void consume()
        {
                if (inputState->guessing == 0)
                {
                        int c = LA(1);
                        if (caseSensitive)
                        {
                                append(c);
                        }
                        else
                        {
                                // use input.LA(), not LA(), to get original case
                                // CharScanner.LA() would toLower it.
                                append(inputState->getInput().LA(1));
                        }

                        // RK: in a sense I don't like this automatic handling.
                        if (c == '\t')
                                tab();
                        else
                                inputState->column++;
                }
                inputState->getInput().consume();
        }

        /** Consume chars until one matches the given char */
        virtual void consumeUntil(int c)
        {
                for(;;)
                {
                        int la_1 = LA(1);
                        if( la_1 == EOF_CHAR || la_1 == c )
                                break;
                        consume();
                }
        }

        /** Consume chars until one matches the given set */
        virtual void consumeUntil(const BitSet& set)
        {
                for(;;)
                {
                        int la_1 = LA(1);
                        if( la_1 == EOF_CHAR || set.member(la_1) )
                                break;
                        consume();
                }
        }

        /// Mark the current position and return a id for it
        virtual unsigned int mark()
        {
                return inputState->getInput().mark();
        }
        /// Rewind the scanner to a previously marked position
        virtual void rewind(unsigned int pos)
        {
                inputState->getInput().rewind(pos);
        }

        /// See if input contains character 'c' throw MismatchedCharException if not
        virtual void match(int c)
        {
                int la_1 = LA(1);
                if ( la_1 != c )
                        throw MismatchedCharException(la_1, c, false, this);
                consume();
        }

        /** See if input contains element from bitset b
         * throw MismatchedCharException if not
         */
        virtual void match(const BitSet& b)
        {
                int la_1 = LA(1);

                if ( !b.member(la_1) )
                        throw MismatchedCharException( la_1, b, false, this );
                consume();
        }

        /** See if input contains string 's' throw MismatchedCharException if not
         * @note the string cannot match EOF
         */
        virtual void match( const char* s )
        {
                while( *s != '\0' )
                {
                        // the & 0xFF is here to prevent sign extension lateron
                        int la_1 = LA(1), c = (*s++ & 0xFF);

                        if ( la_1 != c )
                                throw MismatchedCharException(la_1, c, false, this);

                        consume();
                }
        }
        /** See if input contains string 's' throw MismatchedCharException if not
         * @note the string cannot match EOF
         */
        virtual void match(const ANTLR_USE_NAMESPACE(std)string& s)
        {
                size_t len = s.length();

                for (size_t i = 0; i < len; i++)
                {
                        // the & 0xFF is here to prevent sign extension lateron
                        int la_1 = LA(1), c = (s[i] & 0xFF);

                        if ( la_1 != c )
                                throw MismatchedCharException(la_1, c, false, this);

                        consume();
                }
        }
        /** See if input does not contain character 'c'
         * throw MismatchedCharException if not
         */
        virtual void matchNot(int c)
        {
                int la_1 = LA(1);

                if ( la_1 == c )
                        throw MismatchedCharException(la_1, c, true, this);

                consume();
        }
        /** See if input contains character in range c1-c2
         * throw MismatchedCharException if not
         */
        virtual void matchRange(int c1, int c2)
        {
                int la_1 = LA(1);

                if ( la_1 < c1 || la_1 > c2 )
                        throw MismatchedCharException(la_1, c1, c2, false, this);

                consume();
        }

        virtual bool getCaseSensitive() const
        {
                return caseSensitive;
        }

        virtual void setCaseSensitive(bool t)
        {
                caseSensitive = t;
        }

        virtual bool getCaseSensitiveLiterals() const=0;

        /// Get the line the scanner currently is in (starts at 1)
        virtual int getLine() const
        {
                return inputState->line;
        }

        /// set the line number
        virtual void setLine(int l)
        {
                inputState->line = l;
        }

        /// Get the column the scanner currently is in (starts at 1)
        virtual int getColumn() const
        {
                return inputState->column;
        }
        /// set the column number
        virtual void setColumn(int c)
        {
                inputState->column = c;
        }

        /// get the filename for the file currently used
        virtual const ANTLR_USE_NAMESPACE(std)string& getFilename() const
        {
                return inputState->filename;
        }
        /// Set the filename the scanner is using (used in error messages)
        virtual void setFilename(const ANTLR_USE_NAMESPACE(std)string& f)
        {
                inputState->filename = f;
        }

        virtual bool getCommitToPath() const
        {
                return commitToPath;
        }

        virtual void setCommitToPath(bool commit)
        {
                commitToPath = commit;
        }

        /** return a copy of the current text buffer */
        virtual const ANTLR_USE_NAMESPACE(std)string& getText() const
        {
                return text;
        }

        virtual void setText(const ANTLR_USE_NAMESPACE(std)string& s)
        {
                text = s;
        }

        virtual void resetText()
        {
                text = "";
                inputState->tokenStartColumn = inputState->column;
                inputState->tokenStartLine = inputState->line;
        }

        virtual RefToken getTokenObject() const
        {
                return _returnToken;
        }

        /** Used to keep track of line breaks, needs to be called from
         * within generated lexers when a \n \r is encountered.
         */
        virtual void newline()
        {
                ++inputState->line;
                inputState->column = 1;
        }

        /** Advance the current column number by an appropriate amount according
         * to the tabsize. This method needs to be explicitly called from the
         * lexer rules encountering tabs.
         */
        virtual void tab()
        {
                int c = getColumn();
                int nc = ( ((c-1)/tabsize) + 1) * tabsize + 1;      // calculate tab stop
                setColumn( nc );
        }
        /// set the tabsize. Returns the old tabsize
        int setTabsize( int size )
        {
                int oldsize = tabsize;
                tabsize = size;
                return oldsize;
        }
        /// Return the tabsize used by the scanner
        int getTabSize() const
        {
                return tabsize;
        }

        /** Report exception errors caught in nextToken() */
        virtual void reportError(const RecognitionException& e);

        /** Parser error-reporting function can be overridden in subclass */
        virtual void reportError(const ANTLR_USE_NAMESPACE(std)string& s);

        /** Parser warning-reporting function can be overridden in subclass */
        virtual void reportWarning(const ANTLR_USE_NAMESPACE(std)string& s);

        virtual InputBuffer& getInputBuffer()
        {
                return inputState->getInput();
        }

        virtual LexerSharedInputState getInputState()
        {
                return inputState;
        }

        /** set the input state for the lexer.
         * @note state is a reference counted object, hence no reference */
        virtual void setInputState(LexerSharedInputState state)
        {
                inputState = state;
        }

        /// Set the factory for created tokens
        virtual void setTokenObjectFactory(factory_type factory)
        {
                tokenFactory = factory;
        }

        /** Test the token text against the literals table
         * Override this method to perform a different literals test
         */
        virtual int testLiteralsTable(int ttype) const
        {
                ANTLR_USE_NAMESPACE(std)map<ANTLR_USE_NAMESPACE(std)string,int,CharScannerLiteralsLess>::const_iterator i = literals.find(text);
                if (i != literals.end())
                        ttype = (*i).second;
                return ttype;
        }

        /** Test the text passed in against the literals table
         * Override this method to perform a different literals test
         * This is used primarily when you want to test a portion of
         * a token
         */
        virtual int testLiteralsTable(const ANTLR_USE_NAMESPACE(std)string& txt,int ttype) const
        {
                ANTLR_USE_NAMESPACE(std)map<ANTLR_USE_NAMESPACE(std)string,int,CharScannerLiteralsLess>::const_iterator i = literals.find(txt);
                if (i != literals.end())
                        ttype = (*i).second;
                return ttype;
        }

        /// Override this method to get more specific case handling
        virtual int toLower(int c) const
        {
                // test on EOF_CHAR for buggy (?) STLPort tolower (or HPUX tolower?)
                // also VC++ 6.0 does this. (see fix 422 (is reverted by this fix)
                // this one is more structural. Maybe make this configurable.
                return (c == EOF_CHAR ? EOF_CHAR : tolower(c));
        }

        /** This method is called by YourLexer::nextToken() when the lexer has
         *  hit EOF condition.  EOF is NOT a character.
         *  This method is not called if EOF is reached during
         *  syntactic predicate evaluation or during evaluation
         *  of normal lexical rules, which presumably would be
         *  an IOException.  This traps the "normal" EOF condition.
         *
         *  uponEOF() is called after the complete evaluation of
         *  the previous token and only if your parser asks
         *  for another token beyond that last non-EOF token.
         *
         *  You might want to throw token or char stream exceptions
         *  like: "Heh, premature eof" or a retry stream exception
         *  ("I found the end of this file, go back to referencing file").
         */
        virtual void uponEOF()
        {
        }

        /// Methods used to change tracing behavior
        virtual void traceIndent();
        virtual void traceIn(const char* rname);
        virtual void traceOut(const char* rname);

#ifndef NO_STATIC_CONSTS
        static const int EOF_CHAR = EOF;
#else
        enum {
                EOF_CHAR = EOF
        };
#endif
protected:
        ANTLR_USE_NAMESPACE(std)string text; ///< Text of current token
        /// flag indicating wether consume saves characters
        bool saveConsumedInput;
        factory_type tokenFactory;                              ///< Factory for tokens
        bool caseSensitive;                                             ///< Is this lexer case sensitive
        ANTLR_USE_NAMESPACE(std)map<ANTLR_USE_NAMESPACE(std)string,int,CharScannerLiteralsLess> literals; // set by subclass

        RefToken _returnToken;          ///< used to return tokens w/o using return val

        /// Input state, gives access to input stream, shared among different lexers
        LexerSharedInputState inputState;

        /** Used during filter mode to indicate that path is desired.
         * A subsequent scan error will report an error as usual
         * if acceptPath=true;
         */
        bool commitToPath;

        int tabsize;    ///< tab size the scanner uses.

        /// Create a new RefToken of type t
        virtual RefToken makeToken(int t)
        {
                RefToken tok = tokenFactory();
                tok->setType(t);
                tok->setColumn(inputState->tokenStartColumn);
                tok->setLine(inputState->tokenStartLine);
                return tok;
        }

        /** Tracer class, used when -traceLexer is passed to antlr
         */
        class Tracer {
        private:
                CharScanner* parser;
                const char* text;

                Tracer(const Tracer& other);                                    // undefined
                Tracer& operator=(const Tracer& other);         // undefined
        public:
                Tracer( CharScanner* p,const char* t )
                : parser(p), text(t)
                {
                        parser->traceIn(text);
                }
                ~Tracer()
                {
                        parser->traceOut(text);
                }
        };

        int traceDepth;
private:
        CharScanner( const CharScanner& other );                                        // undefined
        CharScanner& operator=( const CharScanner& other );     // undefined

#ifndef NO_STATIC_CONSTS
        static const int NO_CHAR = 0;
#else
        enum {
                NO_CHAR = 0
        };
#endif
};

inline int CharScanner::LA(unsigned int i)
{
        int c = inputState->getInput().LA(i);

        if ( caseSensitive )
                return c;
        else
                return toLower(c);      // VC 6 tolower bug caught in toLower.
}

inline bool CharScannerLiteralsLess::operator() (const ANTLR_USE_NAMESPACE(std)string& x,const ANTLR_USE_NAMESPACE(std)string& y) const
{
        if (scanner->getCaseSensitiveLiterals())
                return ANTLR_USE_NAMESPACE(std)less<ANTLR_USE_NAMESPACE(std)string>()(x,y);
        else
        {
#ifdef NO_STRCASECMP
                return (stricmp(x.c_str(),y.c_str())<0);
#else
                return (strcasecmp(x.c_str(),y.c_str())<0);
#endif
        }
}

#ifdef ANTLR_CXX_SUPPORTS_NAMESPACE
}
#endif

#endif //INC_CharScanner_hpp__