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//===- FlexLexer.h --------------------------------------------------------===//
//
//                     The MCLinker Project
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//

// -*-C++-*-
// FlexLexer.h -- define interfaces for lexical analyzer classes generated
// by flex

// Copyright (c) 1993 The Regents of the University of California.
// All rights reserved.
//
// This code is derived from software contributed to Berkeley by
// Kent Williams and Tom Epperly.
//
//  Redistribution and use in source and binary forms, with or without
//  modification, are permitted provided that the following conditions
//  are met:

//  1. Redistributions of source code must retain the above copyright
//  notice, this list of conditions and the following disclaimer.
//  2. Redistributions in binary form must reproduce the above copyright
//  notice, this list of conditions and the following disclaimer in the
//  documentation and/or other materials provided with the distribution.

//  Neither the name of the University nor the names of its contributors
//  may be used to endorse or promote products derived from this software
//  without specific prior written permission.

//  THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
//  IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
//  WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
//  PURPOSE.

// This file defines FlexLexer, an abstract class which specifies the
// external interface provided to flex C++ lexer objects, and yyFlexLexer,
// which defines a particular lexer class.
//
// If you want to create multiple lexer classes, you use the -P flag
// to rename each yyFlexLexer to some other xxFlexLexer.  You then
// include <FlexLexer.h> in your other sources once per lexer class:
//
//	#undef yyFlexLexer
//	#define yyFlexLexer xxFlexLexer
//	#include <FlexLexer.h>
//
//	#undef yyFlexLexer
//	#define yyFlexLexer zzFlexLexer
//	#include <FlexLexer.h>
//	...

#ifndef __FLEX_LEXER_H
// Never included before - need to define base class.
#define __FLEX_LEXER_H

#include <iostream>
#ifndef FLEX_STD
#define FLEX_STD std::
#endif

extern "C++" {
struct yy_buffer_state;
typedef int yy_state_type;

class FlexLexer {
 public:
  virtual ~FlexLexer() {}

  const char* YYText() const { return yytext; }
  int YYLeng() const { return yyleng; }

  virtual void yy_switch_to_buffer(struct yy_buffer_state* new_buffer) = 0;
  virtual struct yy_buffer_state* yy_create_buffer(FLEX_STD istream* s,
                                                   int size) = 0;
  virtual void yy_delete_buffer(struct yy_buffer_state* b) = 0;
  virtual void yyrestart(FLEX_STD istream* s) = 0;

  virtual int yylex() = 0;

  // Call yylex with new input/output sources.
  int yylex(FLEX_STD istream* new_in, FLEX_STD ostream* new_out = 0) {
    switch_streams(new_in, new_out);
    return yylex();
  }

  // Switch to new input/output streams.  A nil stream pointer
  // indicates "keep the current one".
  virtual void switch_streams(FLEX_STD istream* new_in = 0,
                              FLEX_STD ostream* new_out = 0) = 0;

  int lineno() const { return yylineno; }

  int debug() const { return yy_flex_debug; }
  void set_debug(int flag) { yy_flex_debug = flag; }

 protected:
  char* yytext;
  int yyleng;
  int yylineno;       // only maintained if you use %option yylineno
  int yy_flex_debug;  // only has effect with -d or "%option debug"
};
}
#endif  // FLEXLEXER_H

#if defined(yyFlexLexer) || !defined(yyFlexLexerOnce)
// Either this is the first time through (yyFlexLexerOnce not defined),
// or this is a repeated include to define a different flavor of
// yyFlexLexer, as discussed in the flex manual.
#define yyFlexLexerOnce

extern "C++" {
class yyFlexLexer : public FlexLexer {
 public:
  // arg_yyin and arg_yyout default to the cin and cout, but we
  // only make that assignment when initializing in yylex().
  yyFlexLexer(FLEX_STD istream* arg_yyin = 0, FLEX_STD ostream* arg_yyout = 0);

  virtual ~yyFlexLexer();

  void yy_switch_to_buffer(struct yy_buffer_state* new_buffer);
  struct yy_buffer_state* yy_create_buffer(FLEX_STD istream* s, int size);
  void yy_delete_buffer(struct yy_buffer_state* b);
  void yyrestart(FLEX_STD istream* s);

  void yypush_buffer_state(struct yy_buffer_state* new_buffer);
  void yypop_buffer_state();

  virtual int yylex();
  virtual void switch_streams(FLEX_STD istream* new_in,
                              FLEX_STD ostream* new_out = 0);
  virtual int yywrap();

 protected:
  virtual int LexerInput(char* buf, int max_size);
  virtual void LexerOutput(const char* buf, int size);
  virtual void LexerError(const char* msg);

  void yyunput(int c, char* buf_ptr);
  int yyinput();

  void yy_load_buffer_state();
  void yy_init_buffer(struct yy_buffer_state* b, FLEX_STD istream* s);
  void yy_flush_buffer(struct yy_buffer_state* b);

  int yy_start_stack_ptr;
  int yy_start_stack_depth;
  int* yy_start_stack;

  void yy_push_state(int new_state);
  void yy_pop_state();
  int yy_top_state();

  yy_state_type yy_get_previous_state();
  yy_state_type yy_try_NUL_trans(yy_state_type current_state);
  int yy_get_next_buffer();

  FLEX_STD istream* yyin;   // input source for default LexerInput
  FLEX_STD ostream* yyout;  // output sink for default LexerOutput

  // yy_hold_char holds the character lost when yytext is formed.
  char yy_hold_char;

  // Number of characters read into yy_ch_buf.
  int yy_n_chars;

  // Points to current character in buffer.
  char* yy_c_buf_p;

  int yy_init;   // whether we need to initialize
  int yy_start;  // start state number

  // Flag which is used to allow yywrap()'s to do buffer switches
  // instead of setting up a fresh yyin.  A bit of a hack ...
  int yy_did_buffer_switch_on_eof;

  size_t yy_buffer_stack_top;               /**< index of top of stack. */
  size_t yy_buffer_stack_max;               /**< capacity of stack. */
  struct yy_buffer_state** yy_buffer_stack; /**< Stack as an array. */
  void yyensure_buffer_stack(void);

  // The following are not always needed, but may be depending
  // on use of certain flex features (like REJECT or yymore()).

  yy_state_type yy_last_accepting_state;
  char* yy_last_accepting_cpos;

  yy_state_type* yy_state_buf;
  yy_state_type* yy_state_ptr;

  char* yy_full_match;
  int* yy_full_state;
  int yy_full_lp;

  int yy_lp;
  int yy_looking_for_trail_begin;

  int yy_more_flag;
  int yy_more_len;
  int yy_more_offset;
  int yy_prev_more_offset;
};
}

#endif  // yyFlexLexer || ! yyFlexLexerOnce