src/lyxlex.h

   1 // -*- C++ -*-
   2 //  Generalized simple lexical analizer.
   3 //  It can be used for simple syntax parsers, like lyxrc,
   4 //  texclass and others to come.   [asierra30/03/96]
   5 //
   6 //   (C) 1996 Lyx Team.
   7 #ifndef _LYXLEX_H
   8 #define _LYXLEX_H
   9
  10 #ifdef __GNUG__
  11 #pragma interface
  12 #endif
  13
  14 #include <stdio.h>
  15 #include "LString.h"
  16
  17 ///
  18 struct keyword_item {
  19         ///
  20         char const* tag;
  21         ///
  22         short code;
  23 };
  24
  25 /*@Doc:
  26   Generalized simple lexical analizer.
  27   It can be used for simple syntax parsers, like lyxrc,
  28   texclass and others to come.
  29   See lyxrc.C for an example of usage.
  30   */
  31 class LyXLex {
  32 public:
  33         ///
  34         LyXLex (keyword_item*, int);
  35         ///
  36         ~LyXLex() { if (file && owns_file) fclose(file); };
  37
  38         /// Lex basic codes
  39         enum {
  40                 ///
  41                 LEX_UNDEF = -1,
  42                 ///
  43                 LEX_FEOF  = -2,
  44                 ///
  45                 LEX_DATA  = -3,
  46                 ///
  47                 LEX_TOKEN = -4
  48         };
  49
  50         /// file is open and end of file is not reached
  51         bool IsOK();
  52         /// return true if able to open file, else false
  53         bool setFile(string const & filename);
  54         /// if file is already read from, line numbers will be wrong.
  55         // should be removed
  56         void setFile(FILE *f);
  57         ///
  58         // should be removed
  59         FILE *getFile() { return file; }
  60         /// Danger! Don't use it unless you know what you are doing.
  61         void setLineNo(int l) { lineno = l; }
  62         /// returns a lex code
  63         int lex();
  64
  65         /** Just read athe next word. If esc is true remember that
  66           some chars might be escaped: "\ atleast */
  67         bool next(bool esc = false);
  68
  69         /** Read next token. This one is almost the same as next,
  70           but it will consider " as a regular character and always
  71           split a word if it contains a backslash.
  72           */
  73         bool nextToken();
  74
  75         ///
  76         int GetLineNo() { return lineno; }
  77         ///
  78         int GetInteger();
  79         ///
  80         bool GetBool();
  81         ///
  82         float GetFloat();
  83         ///
  84         string GetString() const;
  85
  86         /// get a long string, ended by the tag `endtag'
  87         string getLongString(string const &endtoken);
  88
  89         ///
  90         bool EatLine();
  91         ///
  92         int FindToken(char const* string[]);
  93         ///
  94         int CheckToken(char const* string[], int print_error);
  95
  96         ///
  97         char const *text() const { return &buff[0]; }
  98
  99         /** Pushes a token list on a stack and replaces it with a new one.
 100          */
 101         void pushTable(keyword_item*, int);
 102
 103         /** Pops a token list into void and replaces it with the one now
 104           on top of the stack.
 105           */
 106         void popTable();
 107
 108         /** Prints an error message with the corresponding line number
 109           and file name. If message contains the substring `$$Token',
 110           it is replaced with the value of GetString()
 111           */
 112         void printError(string const & message);
 113
 114         /**
 115           Prints the current token table on cerr.
 116           */
 117         void printTable();
 118 protected:
 119         ///
 120         enum {
 121         ///
 122                 LEX_MAX_BUFF = 2048
 123         };
 124
 125         ///
 126         struct pushed_table {
 127                 ///
 128                 pushed_table(){
 129                         next=0;
 130                         table_elem=0;
 131                 }
 132                 ///
 133                 pushed_table *next;
 134                 ///
 135                 keyword_item *table_elem;
 136                 ///
 137                 int table_siz;
 138         };
 139
 140         ///
 141         FILE *file;
 142         ///
 143         bool owns_file;
 144         ///
 145         string name;
 146         ///
 147         int lineno;
 148         ///
 149         keyword_item *table;
 150         ///
 151         int no_items;
 152         ///
 153         char buff[LEX_MAX_BUFF];
 154         ///
 155         pushed_table *pushed;
 156         ///
 157         int search_kw(char const * const) const;
 158         ///
 159         short status;
 160 };
 161
 162
 163 inline
 164 bool LyXLex::IsOK()
 165 {
 166         return (file && !feof(file));
 167 }
 168
 169 #endif