xref: /freebsd/contrib/flex/src/FlexLexer.h (revision 7e38239042df09edbbdc443ccb4825f9155c6bb7)
1 // -*-C++-*-
2 // FlexLexer.h -- define interfaces for lexical analyzer classes generated
3 // by flex
4 
5 // Copyright (c) 1993 The Regents of the University of California.
6 // All rights reserved.
7 //
8 // This code is derived from software contributed to Berkeley by
9 // Kent Williams and Tom Epperly.
10 //
11 //  Redistribution and use in source and binary forms, with or without
12 //  modification, are permitted provided that the following conditions
13 //  are met:
14 
15 //  1. Redistributions of source code must retain the above copyright
16 //  notice, this list of conditions and the following disclaimer.
17 //  2. Redistributions in binary form must reproduce the above copyright
18 //  notice, this list of conditions and the following disclaimer in the
19 //  documentation and/or other materials provided with the distribution.
20 
21 //  Neither the name of the University nor the names of its contributors
22 //  may be used to endorse or promote products derived from this software
23 //  without specific prior written permission.
24 
25 //  THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
26 //  IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
27 //  WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
28 //  PURPOSE.
29 
30 // This file defines FlexLexer, an abstract class which specifies the
31 // external interface provided to flex C++ lexer objects, and yyFlexLexer,
32 // which defines a particular lexer class.
33 //
34 // If you want to create multiple lexer classes, you use the -P flag
35 // to rename each yyFlexLexer to some other xxFlexLexer.  You then
36 // include <FlexLexer.h> in your other sources once per lexer class:
37 //
38 //      #undef yyFlexLexer
39 //      #define yyFlexLexer xxFlexLexer
40 //      #include <FlexLexer.h>
41 //
42 //      #undef yyFlexLexer
43 //      #define yyFlexLexer zzFlexLexer
44 //      #include <FlexLexer.h>
45 //      ...
46 
47 #ifndef __FLEX_LEXER_H
48 // Never included before - need to define base class.
49 #define __FLEX_LEXER_H
50 
51 #include <iostream>
52 
53 extern "C++" {
54 
55 struct yy_buffer_state;
56 typedef int yy_state_type;
57 
58 class FlexLexer
59 {
60 public:
~FlexLexer()61   virtual ~FlexLexer()        { }
62 
YYText()63   const char* YYText() const  { return yytext; }
YYLeng()64   int YYLeng()        const   { return yyleng; }
65 
66   virtual void
67   yy_switch_to_buffer( yy_buffer_state* new_buffer ) = 0;
68   virtual yy_buffer_state* yy_create_buffer( std::istream* s, int size ) = 0;
69   virtual yy_buffer_state* yy_create_buffer( std::istream& s, int size ) = 0;
70   virtual void yy_delete_buffer( yy_buffer_state* b ) = 0;
71   virtual void yyrestart( std::istream* s ) = 0;
72   virtual void yyrestart( std::istream& s ) = 0;
73 
74   virtual int yylex() = 0;
75 
76   // Call yylex with new input/output sources.
yylex(std::istream & new_in,std::ostream & new_out)77   int yylex( std::istream& new_in, std::ostream& new_out )
78   {
79     switch_streams( new_in, new_out );
80     return yylex();
81   }
82 
83   int yylex( std::istream* new_in, std::ostream* new_out = 0)
84   {
85     switch_streams( new_in, new_out );
86     return yylex();
87   }
88 
89   // Switch to new input/output streams.  A nil stream pointer
90   // indicates "keep the current one".
91   virtual void switch_streams( std::istream* new_in,
92                                std::ostream* new_out ) = 0;
93   virtual void switch_streams( std::istream& new_in,
94                                std::ostream& new_out ) = 0;
95 
lineno()96   int lineno() const          { return yylineno; }
97 
debug()98   int debug() const           { return yy_flex_debug; }
set_debug(int flag)99   void set_debug( int flag )  { yy_flex_debug = flag; }
100 
101 protected:
102   char* yytext;
103   int yyleng;
104   int yylineno;       // only maintained if you use %option yylineno
105   int yy_flex_debug;  // only has effect with -d or "%option debug"
106 };
107 
108 }
109 #endif // FLEXLEXER_H
110 
111 #if defined(yyFlexLexer) || ! defined(yyFlexLexerOnce)
112 // Either this is the first time through (yyFlexLexerOnce not defined),
113 // or this is a repeated include to define a different flavor of
114 // yyFlexLexer, as discussed in the flex manual.
115 # define yyFlexLexerOnce
116 
117 extern "C++" {
118 
119 class yyFlexLexer : public FlexLexer {
120 public:
121   // arg_yyin and arg_yyout default to the cin and cout, but we
122   // only make that assignment when initializing in yylex().
123   yyFlexLexer( std::istream& arg_yyin, std::ostream& arg_yyout );
124   yyFlexLexer( std::istream* arg_yyin = 0, std::ostream* arg_yyout = 0 );
125 private:
126   void ctor_common();
127 
128 public:
129 
130   virtual ~yyFlexLexer();
131 
132   void yy_switch_to_buffer( yy_buffer_state* new_buffer );
133   yy_buffer_state* yy_create_buffer( std::istream* s, int size );
134   yy_buffer_state* yy_create_buffer( std::istream& s, int size );
135   void yy_delete_buffer( yy_buffer_state* b );
136   void yyrestart( std::istream* s );
137   void yyrestart( std::istream& s );
138 
139   void yypush_buffer_state( yy_buffer_state* new_buffer );
140   void yypop_buffer_state();
141 
142   virtual int yylex();
143   virtual void switch_streams( std::istream& new_in, std::ostream& new_out );
144   virtual void switch_streams( std::istream* new_in = 0, std::ostream* new_out = 0 );
145   virtual int yywrap();
146 
147 protected:
148   virtual int LexerInput( char* buf, int max_size );
149   virtual void LexerOutput( const char* buf, int size );
150   virtual void LexerError( const char* msg );
151 
152   void yyunput( int c, char* buf_ptr );
153   int yyinput();
154 
155   void yy_load_buffer_state();
156   void yy_init_buffer( yy_buffer_state* b, std::istream& s );
157   void yy_flush_buffer( yy_buffer_state* b );
158 
159   int yy_start_stack_ptr;
160   int yy_start_stack_depth;
161   int* yy_start_stack;
162 
163   void yy_push_state( int new_state );
164   void yy_pop_state();
165   int yy_top_state();
166 
167   yy_state_type yy_get_previous_state();
168   yy_state_type yy_try_NUL_trans( yy_state_type current_state );
169   int yy_get_next_buffer();
170 
171   std::istream yyin;  // input source for default LexerInput
172   std::ostream yyout; // output sink for default LexerOutput
173 
174   // yy_hold_char holds the character lost when yytext is formed.
175   char yy_hold_char;
176 
177   // Number of characters read into yy_ch_buf.
178   int yy_n_chars;
179 
180   // Points to current character in buffer.
181   char* yy_c_buf_p;
182 
183   int yy_init;                // whether we need to initialize
184   int yy_start;               // start state number
185 
186   // Flag which is used to allow yywrap()'s to do buffer switches
187   // instead of setting up a fresh yyin.  A bit of a hack ...
188   int yy_did_buffer_switch_on_eof;
189 
190 
191   size_t yy_buffer_stack_top; /**< index of top of stack. */
192   size_t yy_buffer_stack_max; /**< capacity of stack. */
193   yy_buffer_state ** yy_buffer_stack; /**< Stack as an array. */
194   void yyensure_buffer_stack(void);
195 
196   // The following are not always needed, but may be depending
197   // on use of certain flex features (like REJECT or yymore()).
198 
199   yy_state_type yy_last_accepting_state;
200   char* yy_last_accepting_cpos;
201 
202   yy_state_type* yy_state_buf;
203   yy_state_type* yy_state_ptr;
204 
205   char* yy_full_match;
206   int* yy_full_state;
207   int yy_full_lp;
208 
209   int yy_lp;
210   int yy_looking_for_trail_begin;
211 
212   int yy_more_flag;
213   int yy_more_len;
214   int yy_more_offset;
215   int yy_prev_more_offset;
216 };
217 
218 }
219 
220 #endif // yyFlexLexer || ! yyFlexLexerOnce
221