src/common/lexer.l

   1 SIGN            [+-]
   2 DIGIT           [0-9]
   3 ALPHA           [a-zA-Z_]
   4 ALPHADIGIT      [a-zA-Z_0-9]
   5 STRINGCHAR      [^"\\]
   6 WORDCHAR        [^'\\]
   7
   8 %{
   9 /*
  10  * File:         lexer.l
  11  * Description:  Lexical analyser for PROLOGIO; can be used with
  12  *               either lex and flex.
  13  */
  14 #include <string.h>
  15 #include <unistd.h>
  16
  17 /* +++steve162e: added, otherwise, PROIO_input will be undefined (at least under LINUX)
  18              please check, if this is also TRUE under other UNIXes.
  19  */
  20
  21 #if defined(FLEX_SCANNER) && defined(_LINUX)
  22 #define PROIO_input my_input
  23 #endif
  24 /* ---steve162e */
  25
  26 #include "wx/expr.h"
  27
  28 #ifdef wx_x
  29 extern char *malloc();
  30 #endif
  31 #define Return(x) return x;
  32
  33 #if defined(VMS) && !defined(strdup)
  34 #define strdup(s) (strcpy((char *)malloc(strlen(s)+1), s));
  35 #endif
  36
  37 static size_t lex_buffer_length = 0;
  38 static const char *lex_buffer = NULL;
  39 static size_t lex_string_ptr = 0;
  40 static int lex_read_from_string = 0;
  41
  42 static int my_input(void);
  43 static int my_unput(char);
  44
  45 #ifdef FLEX_SCANNER
  46 #undef YY_INPUT
  47 # define YY_INPUT(buf,result,max_size) \
  48    if (lex_read_from_string) \
  49    {  int c = my_input(); result = (c == 0) ? YY_NULL : ((buf)[0]=(c), 1); } \
  50    else \
  51         if ( (result = read( fileno(yyin), (char *) buf, max_size )) < 0 ) \
  52             YY_FATAL_ERROR( "read() in flex scanner failed" );
  53 #else
  54 # undef unput
  55 # define unput(_c) my_unput(_c)
  56 #endif
  57
  58 %}
  59
  60 %%
  61
  62 {SIGN}?{DIGIT}+                   {yylval.s = strdup(yytext); Return(INTEGER);}
  63
  64 "e"                               Return(EXP);
  65
  66 {ALPHA}{ALPHADIGIT}*              {yylval.s = strdup(yytext); Return(WORD);}
  67
  68 "'"{WORDCHAR}*"'"                 {int len = strlen(yytext);
  69                                    yytext[len-1] = 0;
  70                                    yylval.s = strdup(yytext+1);
  71                                    Return(WORD);}
  72
  73 \"({STRINGCHAR}|\\\"|\|\\\\|\\)*\"  {yylval.s = strdup(yytext); Return(STRING);}
  74
  75 "("                               Return(OPEN);
  76
  77 ")"                               Return(CLOSE);
  78
  79 ","                               Return(COMMA);
  80
  81 "["                               Return(OPEN_SQUARE);
  82
  83 "]"                               Return(CLOSE_SQUARE);
  84
  85 "="                               Return(EQUALS);
  86
  87 "."                               Return(PERIOD);
  88
  89 [ \t]                             ;
  90
  91 \n                                ;
  92
  93 "/*"    {       loop:
  94 #ifdef __cplusplus
  95                           while (yyinput() != '*');
  96                           switch (yyinput())
  97 #else
  98                           while (input() != '*');
  99                           switch (input())
 100 #endif
 101                                   {
 102                                   case '/': break;
 103                                   case '*': unput('*');
 104                                   default: goto loop;
 105                                   }
 106                           }
 107
 108 .                                 Return(ERROR);
 109
 110 %%
 111
 112
 113 #ifdef FLEX_SCANNER
 114 static int lex_input() {
 115   return input();
 116 }
 117 #else   /* BSD/AT&T lex */
 118 #ifndef input
 119 # error "Sorry, but need either flex or AT&T lex"
 120 #endif
 121 static int lex_input() {
 122   return input();
 123 }
 124 /* # undef unput
 125 # define unput(_c) my_unput(_c)
 126 */
 127
 128 # undef input
 129 # define input() my_input()
 130 static int my_unput(char c)
 131 {
 132   if (lex_read_from_string) {
 133     /* Make sure we have something */
 134     if (lex_string_ptr) {
 135       if (c == '\n') yylineno--;
 136       lex_string_ptr--;
 137     }
 138   } else {
 139     yytchar= (c);if(yytchar=='\n')yylineno--;*yysptr++=yytchar;
 140 /*    unput(c); Causes infinite recursion! */
 141   }
 142   return c;
 143 }
 144
 145 #endif
 146
 147 /* Public */
 148 void LexFromFile(FILE *fd)
 149 {
 150   lex_read_from_string = 0;
 151   yyin = fd;
 152   /* Don't know why this is necessary, but otherwise
 153    * lex only works _once_!
 154    */
 155 #ifdef FLEX_SCANNER
 156   yyrestart(fd);
 157   yy_init = 1;
 158 #endif
 159 }
 160
 161 void LexFromString(char *buffer)
 162 {
 163   lex_read_from_string = 1;
 164   lex_buffer = buffer;
 165   lex_buffer_length = strlen(buffer);
 166   lex_string_ptr = 0;
 167   /* Don't know why this is necessary, but otherwise
 168    * lex only works _once_!
 169    */
 170 #ifdef FLEX_SCANNER
 171   yy_init = 1;
 172 #endif
 173 }
 174
 175 static int my_input( void )
 176 {
 177   if (lex_read_from_string) {
 178     if (lex_string_ptr == lex_buffer_length)
 179       return 0;
 180     else {
 181       char c = lex_buffer[lex_string_ptr++];
 182 #ifndef FLEX_SCANNER
 183       if (c == '\n') yylineno++;
 184 #endif
 185       return c;
 186     }
 187   } else {
 188     return lex_input();
 189   }
 190 }
 191
 192 void wxExprCleanUp()
 193 {
 194 #ifdef FLEX_SCANNER
 195         if (yy_current_buffer)
 196                 yy_delete_buffer(yy_current_buffer);
 197 #endif
 198 }