scanner.h

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#ifndef _RE2C_PARSE_SCANNER_
#define _RE2C_PARSE_SCANNER_

#include "src/util/c99_stdint.h"
#include <stddef.h>
#include <string>

#include "src/parse/input.h"
#include "src/util/attribute.h"
#include "src/util/forbid_copy.h"

namespace re2c
{

class Range;
class RegExp;
struct OutputFile;

struct ScannerState
{
    enum lexer_state_t
    {
        LEX_NORMAL,
        LEX_FLEX_NAME
    };

    // positioning
    char * tok;
    char * ptr;
    char * cur;
    char * pos;
    char * ctx;

    // buffer
    char * bot;
    char * lim;
    char * top;
    char * eof;

    ptrdiff_t tchar;
    uint32_t tline;
    uint32_t cline;

    bool in_parse;
    lexer_state_t lexer_state;

    ScannerState ();
    ScannerState (const ScannerState &);
    ScannerState & operator = (const ScannerState &);
};

class Scanner: private ScannerState
{
    static const uint32_t BSIZE;

    Input & in;
public:
    OutputFile & out;

private:
    void fill (uint32_t);
    void set_sourceline ();
    uint32_t lex_cls_chr();
    uint32_t lex_str_chr(char quote, bool &end);
    RegExp *lex_cls(bool neg);
    RegExp *lex_str(char quote, bool casing);
    RegExp *schr(uint32_t c) const;
    RegExp *ichr(uint32_t c) const;
    RegExp *cls(Range *r) const;

    void lex_conf ();
    void lex_conf_assign ();
    void lex_conf_semicolon ();
    int32_t lex_conf_number ();
    std::string lex_conf_string ();

    size_t tok_len () const;

public:
    Scanner(Input &, OutputFile &);
    ~Scanner();

    enum ParseMode {
        Stop,
        Parse,
        Reuse,
        Rules
    };

    ParseMode echo();
    int scan();
    void reuse();

    void save_state(ScannerState&) const;
    void restore_state(const ScannerState&);

    uint32_t get_cline() const;
    uint32_t get_line() const;
    const std::string & get_fname () const;
    void set_in_parse(bool new_in_parse);
    void fatal_at(uint32_t line, ptrdiff_t ofs, const char *msg) const;
    void fatalf_at(uint32_t line, const char*, ...) const RE2C_GXX_ATTRIBUTE ((format (printf, 3, 4)));
    void fatalf(const char*, ...) const RE2C_GXX_ATTRIBUTE ((format (printf, 2, 3)));
    void fatal(const char*) const;
    void fatal(ptrdiff_t, const char*) const;

    RegExp * mkDiff (RegExp * e1, RegExp * e2) const;
    RegExp * mkDot () const;
    RegExp * mkDefault () const;

    FORBID_COPY (Scanner);
};

inline size_t Scanner::tok_len () const
{
    // lexing and fill procedures must maintain: token pointer <= cursor pointer
    return static_cast<size_t> (cur - tok);
}

inline const std::string & Scanner::get_fname () const
{
    return in.file_name;
}

inline uint32_t Scanner::get_cline() const
{
    return cline;
}

inline uint32_t Scanner::get_line() const
{
    return in_parse ? tline : cline;
}

inline void Scanner::save_state(ScannerState& state) const
{
    state = *this;
}

inline void Scanner::fatal(const char *msg) const
{
    fatal(0, msg);
}

} // end namespace re2c

#endif // _RE2C_PARSE_SCANNER_