exp/expression-parser.l

   1 %{
   2
   3 /*
   4  * (C) Copyright 2014, Stephen M. Cameron.
   5  *
   6  *  This program is free software; you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License version 2 as
   8  *  published by the Free Software Foundation.
   9  *
  10  *  This program is distributed in the hope that it will be useful,
  11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  *  GNU General Public License for more details.
  14  *
  15  *  You should have received a copy of the GNU General Public License
  16  *  along with this program; if not, write to the Free Software
  17  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  18  *
  19  */
  20
  21 #include <stdio.h>
  22 #include <string.h>
  23 #include "y.tab.h"
  24
  25 #define YYSTYPE PARSER_VALUE_TYPE
  26
  27 extern int lexer_input(char* buffer, int *nbytes, int buffersize);
  28
  29 #undef YY_INPUT
  30 #define YY_INPUT(buffer, bytes_read, bytes_requested) \
  31                 lexer_input((buffer), &(bytes_read), (bytes_requested))
  32
  33 extern int yyerror(long long *result, double *dresult,
  34                 int *has_error, int *bye, const char *msg);
  35
  36 static void __attribute__((unused)) yyunput(int c,char *buf_ptr);
  37 static int __attribute__((unused)) input(void);
  38
  39 %}
  40
  41 %%
  42
  43
  44 bye     return BYE;
  45 [ \t] ; /* ignore whitespace */
  46 #.+ ; /* ignore comments */
  47 [0-9]*[.][0-9]+ {
  48                         int rc;
  49                         double dval;
  50
  51                         rc = sscanf(yytext, "%lf", &dval);
  52                         if (rc == 1) {
  53                                 yylval.v.dval = dval;
  54                                 yylval.v.ival = (long long) dval;
  55                                 yylval.v.has_dval = 1;
  56                                 yylval.v.has_error = 0;
  57                                 return NUMBER;
  58                         } else {
  59                                 yyerror(0, 0, 0, 0, "bad number\n");
  60                                 yylval.v.has_error = 1;
  61                                 return NUMBER;
  62                         }
  63                 }
  64 0x[0-9a-fA-F]+ {
  65                 int rc, intval;
  66                 rc = sscanf(yytext, "%x", &intval);
  67                 if (rc == 1) {
  68                         yylval.v.ival = intval;
  69                         yylval.v.dval = (double) intval;
  70                         yylval.v.has_dval = 0;
  71                         yylval.v.has_error = 0;
  72                         return NUMBER;
  73                 } else {
  74                         yyerror(0, 0, 0, 0, "bad number\n");
  75                         yylval.v.has_error = 1;
  76                         return NUMBER;
  77                 }
  78         }
  79 [0-9]+  {
  80                 int rc, intval;
  81                 rc = sscanf(yytext, "%d", &intval);
  82                 if (rc == 1) {
  83                         yylval.v.ival = intval;
  84                         yylval.v.dval = (double) intval;
  85                         yylval.v.has_dval = 0;
  86                         yylval.v.has_error = 0;
  87                         return NUMBER;
  88                 } else {
  89                         yyerror(0, 0, 0, 0, "bad number\n");
  90                         yylval.v.has_error = 1;
  91                         return NUMBER;
  92                 }
  93         }
  94 \n      return 0;
  95 [+-/*()]        return yytext[0];
  96 .       {
  97                 yylval.v.has_error = 1;
  98                 return NUMBER;
  99         }
 100 %%
 101