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