xref: /minix/external/bsd/flex/dist/FlexLexer.h (revision 0a6a1f1d)
1 /*	$NetBSD: FlexLexer.h,v 1.2 2014/10/29 18:28:36 christos Exp $	*/
2 
3 // -*-C++-*-
4 // FlexLexer.h -- define interfaces for lexical analyzer classes generated
5 // by flex
6 
7 // Copyright (c) 1993 The Regents of the University of California.
8 // All rights reserved.
9 //
10 // This code is derived from software contributed to Berkeley by
11 // Kent Williams and Tom Epperly.
12 //
13 //  Redistribution and use in source and binary forms, with or without
14 //  modification, are permitted provided that the following conditions
15 //  are met:
16 
17 //  1. Redistributions of source code must retain the above copyright
18 //  notice, this list of conditions and the following disclaimer.
19 //  2. Redistributions in binary form must reproduce the above copyright
20 //  notice, this list of conditions and the following disclaimer in the
21 //  documentation and/or other materials provided with the distribution.
22 
23 //  Neither the name of the University nor the names of its contributors
24 //  may be used to endorse or promote products derived from this software
25 //  without specific prior written permission.
26 
27 //  THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
28 //  IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
29 //  WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
30 //  PURPOSE.
31 
32 // This file defines FlexLexer, an abstract class which specifies the
33 // external interface provided to flex C++ lexer objects, and yyFlexLexer,
34 // which defines a particular lexer class.
35 //
36 // If you want to create multiple lexer classes, you use the -P flag
37 // to rename each yyFlexLexer to some other xxFlexLexer.  You then
38 // include <FlexLexer.h> in your other sources once per lexer class:
39 //
40 //	#undef yyFlexLexer
41 //	#define yyFlexLexer xxFlexLexer
42 //	#include <FlexLexer.h>
43 //
44 //	#undef yyFlexLexer
45 //	#define yyFlexLexer zzFlexLexer
46 //	#include <FlexLexer.h>
47 //	...
48 
49 #ifndef __FLEX_LEXER_H
50 // Never included before - need to define base class.
51 #define __FLEX_LEXER_H
52 
53 #include <iostream>
54 #  ifndef FLEX_STD
55 #    define FLEX_STD std::
56 #  endif
57 
58 extern "C++" {
59 
60 struct yy_buffer_state;
61 typedef int yy_state_type;
62 
63 class FlexLexer {
64 public:
~FlexLexer()65 	virtual ~FlexLexer()	{ }
66 
YYText()67 	const char* YYText() const	{ return yytext; }
YYLeng()68 	int YYLeng()	const	{ return yyleng; }
69 
70 	virtual void
71 		yy_switch_to_buffer( struct yy_buffer_state* new_buffer ) = 0;
72 	virtual struct yy_buffer_state*
73 		yy_create_buffer( FLEX_STD istream* s, int size ) = 0;
74 	virtual void yy_delete_buffer( struct yy_buffer_state* b ) = 0;
75 	virtual void yyrestart( FLEX_STD istream* s ) = 0;
76 
77 	virtual int yylex() = 0;
78 
79 	// Call yylex with new input/output sources.
80 	int yylex( FLEX_STD istream* new_in, FLEX_STD ostream* new_out = 0 )
81 		{
82 		switch_streams( new_in, new_out );
83 		return yylex();
84 		}
85 
86 	// Switch to new input/output streams.  A nil stream pointer
87 	// indicates "keep the current one".
88 	virtual void switch_streams( FLEX_STD istream* new_in = 0,
89 					FLEX_STD ostream* new_out = 0 ) = 0;
90 
lineno()91 	int lineno() const		{ return yylineno; }
92 
debug()93 	int debug() const		{ return yy_flex_debug; }
set_debug(int flag)94 	void set_debug( int flag )	{ yy_flex_debug = flag; }
95 
96 protected:
97 	char* yytext;
98 	int yyleng;
99 	int yylineno;		// only maintained if you use %option yylineno
100 	int yy_flex_debug;	// only has effect with -d or "%option debug"
101 };
102 
103 }
104 #endif // FLEXLEXER_H
105 
106 #if defined(yyFlexLexer) || ! defined(yyFlexLexerOnce)
107 // Either this is the first time through (yyFlexLexerOnce not defined),
108 // or this is a repeated include to define a different flavor of
109 // yyFlexLexer, as discussed in the flex manual.
110 #define yyFlexLexerOnce
111 
112 extern "C++" {
113 
114 class yyFlexLexer : public FlexLexer {
115 public:
116 	// arg_yyin and arg_yyout default to the cin and cout, but we
117 	// only make that assignment when initializing in yylex().
118 	yyFlexLexer( FLEX_STD istream* arg_yyin = 0, FLEX_STD ostream* arg_yyout = 0 );
119 
120 	virtual ~yyFlexLexer();
121 
122 	void yy_switch_to_buffer( struct yy_buffer_state* new_buffer );
123 	struct yy_buffer_state* yy_create_buffer( FLEX_STD istream* s, int size );
124 	void yy_delete_buffer( struct yy_buffer_state* b );
125 	void yyrestart( FLEX_STD istream* s );
126 
127 	void yypush_buffer_state( struct yy_buffer_state* new_buffer );
128 	void yypop_buffer_state();
129 
130 	virtual int yylex();
131 	virtual void switch_streams( FLEX_STD istream* new_in, FLEX_STD ostream* new_out = 0 );
132 	virtual int yywrap();
133 
134 protected:
135 	virtual int LexerInput( char* buf, int max_size );
136 	virtual void LexerOutput( const char* buf, int size );
137 	virtual void LexerError( const char* msg );
138 
139 	void yyunput( int c, char* buf_ptr );
140 	int yyinput();
141 
142 	void yy_load_buffer_state();
143 	void yy_init_buffer( struct yy_buffer_state* b, FLEX_STD istream* s );
144 	void yy_flush_buffer( struct yy_buffer_state* b );
145 
146 	int yy_start_stack_ptr;
147 	int yy_start_stack_depth;
148 	int* yy_start_stack;
149 
150 	void yy_push_state( int new_state );
151 	void yy_pop_state();
152 	int yy_top_state();
153 
154 	yy_state_type yy_get_previous_state();
155 	yy_state_type yy_try_NUL_trans( yy_state_type current_state );
156 	int yy_get_next_buffer();
157 
158 	FLEX_STD istream* yyin;	// input source for default LexerInput
159 	FLEX_STD ostream* yyout;	// output sink for default LexerOutput
160 
161 	// yy_hold_char holds the character lost when yytext is formed.
162 	char yy_hold_char;
163 
164 	// Number of characters read into yy_ch_buf.
165 	int yy_n_chars;
166 
167 	// Points to current character in buffer.
168 	char* yy_c_buf_p;
169 
170 	int yy_init;		// whether we need to initialize
171 	int yy_start;		// start state number
172 
173 	// Flag which is used to allow yywrap()'s to do buffer switches
174 	// instead of setting up a fresh yyin.  A bit of a hack ...
175 	int yy_did_buffer_switch_on_eof;
176 
177 
178 	size_t yy_buffer_stack_top; /**< index of top of stack. */
179 	size_t yy_buffer_stack_max; /**< capacity of stack. */
180 	struct yy_buffer_state ** yy_buffer_stack; /**< Stack as an array. */
181 	void yyensure_buffer_stack(void);
182 
183 	// The following are not always needed, but may be depending
184 	// on use of certain flex features (like REJECT or yymore()).
185 
186 	yy_state_type yy_last_accepting_state;
187 	char* yy_last_accepting_cpos;
188 
189 	yy_state_type* yy_state_buf;
190 	yy_state_type* yy_state_ptr;
191 
192 	char* yy_full_match;
193 	int* yy_full_state;
194 	int yy_full_lp;
195 
196 	int yy_lp;
197 	int yy_looking_for_trail_begin;
198 
199 	int yy_more_flag;
200 	int yy_more_len;
201 	int yy_more_offset;
202 	int yy_prev_more_offset;
203 };
204 
205 }
206 
207 #endif // yyFlexLexer || ! yyFlexLexerOnce
208 
209