Home | History | Annotate | Download | only in flex-2.5.4a
      1 // $Header: /home/daffy/u0/vern/flex/RCS/FlexLexer.h,v 1.19 96/05/25 20:43:02 vern Exp $
      2 
      3 // FlexLexer.h -- define interfaces for lexical analyzer classes generated
      4 //		  by flex
      5 
      6 // Copyright (c) 1993 The Regents of the University of California.
      7 // All rights reserved.
      8 //
      9 // This code is derived from software contributed to Berkeley by
     10 // Kent Williams and Tom Epperly.
     11 //
     12 // Redistribution and use in source and binary forms with or without
     13 // modification are permitted provided that: (1) source distributions retain
     14 // this entire copyright notice and comment, and (2) distributions including
     15 // binaries display the following acknowledgement:  ``This product includes
     16 // software developed by the University of California, Berkeley and its
     17 // contributors'' in the documentation or other materials provided with the
     18 // distribution and in all advertising materials mentioning features or use
     19 // of this software.  Neither the name of the University nor the names of
     20 // its contributors may be used to endorse or promote products derived from
     21 // this software without specific prior written permission.
     22 
     23 // THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
     24 // WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
     25 // MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
     26 
     27 // This file defines FlexLexer, an abstract class which specifies the
     28 // external interface provided to flex C++ lexer objects, and yyFlexLexer,
     29 // which defines a particular lexer class.
     30 //
     31 // If you want to create multiple lexer classes, you use the -P flag
     32 // to rename each yyFlexLexer to some other xxFlexLexer.  You then
     33 // include <FlexLexer.h> in your other sources once per lexer class:
     34 //
     35 //	#undef yyFlexLexer
     36 //	#define yyFlexLexer xxFlexLexer
     37 //	#include <FlexLexer.h>
     38 //
     39 //	#undef yyFlexLexer
     40 //	#define yyFlexLexer zzFlexLexer
     41 //	#include <FlexLexer.h>
     42 //	...
     43 
     44 #ifndef __FLEX_LEXER_H
     45 // Never included before - need to define base class.
     46 #define __FLEX_LEXER_H
     47 #include <iostream.h>
     48 
     49 extern "C++" {
     50 
     51 struct yy_buffer_state;
     52 typedef int yy_state_type;
     53 
     54 class FlexLexer {
     55 public:
     56 	virtual ~FlexLexer()	{ }
     57 
     58 	const char* YYText()	{ return yytext; }
     59 	int YYLeng()		{ return yyleng; }
     60 
     61 	virtual void
     62 		yy_switch_to_buffer( struct yy_buffer_state* new_buffer ) = 0;
     63 	virtual struct yy_buffer_state*
     64 		yy_create_buffer( istream* s, int size ) = 0;
     65 	virtual void yy_delete_buffer( struct yy_buffer_state* b ) = 0;
     66 	virtual void yyrestart( istream* s ) = 0;
     67 
     68 	virtual int yylex() = 0;
     69 
     70 	// Call yylex with new input/output sources.
     71 	int yylex( istream* new_in, ostream* new_out = 0 )
     72 		{
     73 		switch_streams( new_in, new_out );
     74 		return yylex();
     75 		}
     76 
     77 	// Switch to new input/output streams.  A nil stream pointer
     78 	// indicates "keep the current one".
     79 	virtual void switch_streams( istream* new_in = 0,
     80 					ostream* new_out = 0 ) = 0;
     81 
     82 	int lineno() const		{ return yylineno; }
     83 
     84 	int debug() const		{ return yy_flex_debug; }
     85 	void set_debug( int flag )	{ yy_flex_debug = flag; }
     86 
     87 protected:
     88 	char* yytext;
     89 	int yyleng;
     90 	int yylineno;		// only maintained if you use %option yylineno
     91 	int yy_flex_debug;	// only has effect with -d or "%option debug"
     92 };
     93 
     94 }
     95 #endif
     96 
     97 #if defined(yyFlexLexer) || ! defined(yyFlexLexerOnce)
     98 // Either this is the first time through (yyFlexLexerOnce not defined),
     99 // or this is a repeated include to define a different flavor of
    100 // yyFlexLexer, as discussed in the flex man page.
    101 #define yyFlexLexerOnce
    102 
    103 class yyFlexLexer : public FlexLexer {
    104 public:
    105 	// arg_yyin and arg_yyout default to the cin and cout, but we
    106 	// only make that assignment when initializing in yylex().
    107 	yyFlexLexer( istream* arg_yyin = 0, ostream* arg_yyout = 0 );
    108 
    109 	virtual ~yyFlexLexer();
    110 
    111 	void yy_switch_to_buffer( struct yy_buffer_state* new_buffer );
    112 	struct yy_buffer_state* yy_create_buffer( istream* s, int size );
    113 	void yy_delete_buffer( struct yy_buffer_state* b );
    114 	void yyrestart( istream* s );
    115 
    116 	virtual int yylex();
    117 	virtual void switch_streams( istream* new_in, ostream* new_out );
    118 
    119 protected:
    120 	virtual int LexerInput( char* buf, int max_size );
    121 	virtual void LexerOutput( const char* buf, int size );
    122 	virtual void LexerError( const char* msg );
    123 
    124 	void yyunput( int c, char* buf_ptr );
    125 	int yyinput();
    126 
    127 	void yy_load_buffer_state();
    128 	void yy_init_buffer( struct yy_buffer_state* b, istream* s );
    129 	void yy_flush_buffer( struct yy_buffer_state* b );
    130 
    131 	int yy_start_stack_ptr;
    132 	int yy_start_stack_depth;
    133 	int* yy_start_stack;
    134 
    135 	void yy_push_state( int new_state );
    136 	void yy_pop_state();
    137 	int yy_top_state();
    138 
    139 	yy_state_type yy_get_previous_state();
    140 	yy_state_type yy_try_NUL_trans( yy_state_type current_state );
    141 	int yy_get_next_buffer();
    142 
    143 	istream* yyin;	// input source for default LexerInput
    144 	ostream* yyout;	// output sink for default LexerOutput
    145 
    146 	struct yy_buffer_state* yy_current_buffer;
    147 
    148 	// yy_hold_char holds the character lost when yytext is formed.
    149 	char yy_hold_char;
    150 
    151 	// Number of characters read into yy_ch_buf.
    152 	int yy_n_chars;
    153 
    154 	// Points to current character in buffer.
    155 	char* yy_c_buf_p;
    156 
    157 	int yy_init;		// whether we need to initialize
    158 	int yy_start;		// start state number
    159 
    160 	// Flag which is used to allow yywrap()'s to do buffer switches
    161 	// instead of setting up a fresh yyin.  A bit of a hack ...
    162 	int yy_did_buffer_switch_on_eof;
    163 
    164 	// The following are not always needed, but may be depending
    165 	// on use of certain flex features (like REJECT or yymore()).
    166 
    167 	yy_state_type yy_last_accepting_state;
    168 	char* yy_last_accepting_cpos;
    169 
    170 	yy_state_type* yy_state_buf;
    171 	yy_state_type* yy_state_ptr;
    172 
    173 	char* yy_full_match;
    174 	int* yy_full_state;
    175 	int yy_full_lp;
    176 
    177 	int yy_lp;
    178 	int yy_looking_for_trail_begin;
    179 
    180 	int yy_more_flag;
    181 	int yy_more_len;
    182 	int yy_more_offset;
    183 	int yy_prev_more_offset;
    184 };
    185 
    186 #endif
    187