git.ozlabs.org Git - petitboot/blob - discover/grub2/lexer.l

   1
   2 %{
   3 #include "parser.h"
   4 #include <talloc/talloc.h>
   5 %}
   6
   7 %option nounput noinput
   8 %option warn
   9 %option noyywrap
  10 %option stack noyy_top_state
  11 %option reentrant
  12 %option bison-bridge
  13 %option noyyalloc noyyfree noyyrealloc
  14 %option extra-type="struct grub2_parser *"
  15 %option header-file="lexer.h"
  16 %option outfile="lexer.c"
  17
  18 %x sqstring
  19 %x dqstring
  20
  21 WORD    [^{}|&$;<> \t\n'"]+
  22 VARNAME ([[:alpha:]][_[:alnum:]]*|[0-9]|[\?@\*#])
  23
  24 %%
  25
  26  /* discard leading & trailing whitespace, but keep inter-word delimeters */
  27 ^[ \t]+ ;
  28 [ \t]+$ ;
  29 [ \t]*  return TOKEN_DELIM;
  30
  31  /* reserved words */
  32 "[["         return TOKEN_LDSQBRACKET;
  33 "]]"         return TOKEN_RDSQBRACKET;
  34 "case"       return TOKEN_CASE;
  35 "do"         return TOKEN_DO;
  36 "done"       return TOKEN_DONE;
  37 "elif"       return TOKEN_ELIF;
  38 "esac"       return TOKEN_ESAC;
  39 "fi"         return TOKEN_FI;
  40 "for"        return TOKEN_FOR;
  41 "function"   return TOKEN_FUNCTION;
  42 "if"         return TOKEN_IF;
  43 "in"         return TOKEN_IN;
  44 "menuentry"  return TOKEN_MENUENTRY;
  45 "select"     return TOKEN_SELECT;
  46 "then"       return TOKEN_THEN;
  47 "time"       return TOKEN_TIME;
  48 "until"      return TOKEN_UTIL;
  49 "while"      return TOKEN_WHILE;
  50
  51  /* anything that's not a metachar: return as a plain word */
  52 {WORD}  {
  53                 yylval->strval = talloc_strdup(yyscanner, yytext);
  54                 yylval->expand = 0;
  55                 return TOKEN_WORD;
  56         }
  57
  58 \${VARNAME} |
  59 \$\{{VARNAME}\} {
  60                 yylval->strval = talloc_strdup(yyscanner, yytext);
  61                 yylval->expand = 1;
  62                 yylval->split = 1;
  63                 return TOKEN_WORD;
  64         }
  65
  66  /* single-quoted strings: return a single, non-expanded word token */
  67 \'      {
  68                 yy_push_state(sqstring, yyscanner);
  69         }
  70 <sqstring>\' {
  71                 yy_pop_state(yyscanner);
  72                 return TOKEN_WORD;
  73         }
  74 <sqstring>[^']+ {
  75                 yylval->expand = 0;
  76                 yylval->split = 0;
  77                 yylval->strval = talloc_strdup(yyscanner, yytext);
  78         }
  79
  80  /* double-quoted strings: return a single, expanded word token */
  81 \"      {
  82                 yy_push_state(dqstring, yyscanner);
  83         }
  84 <dqstring>\" {
  85                 yy_pop_state(yyscanner);
  86                 return TOKEN_WORD;
  87         }
  88 <dqstring>([^"]|\\\")+ {
  89                 yylval->expand = 1;
  90                 yylval->split = 0;
  91                 yylval->strval = talloc_strdup(yyscanner, yytext);
  92         }
  93
  94
  95  /* blocks */
  96 "{"     return '{';
  97 "}"     return '}';
  98
  99  /* end-of-line */
 100 [ \t]*(;|\n)[ \t]*      return TOKEN_EOL;
 101
 102  /* strip comments */
 103 #.*$    ;
 104
 105
 106 .       printf("unknown token '%s'\n", yytext); exit(1);
 107
 108 %%
 109
 110 struct grub2_parser;
 111
 112 void *yyalloc(size_t bytes, void *yyscanner)
 113 {
 114         struct grub2_parser *parser = yyget_extra(yyscanner);
 115         return talloc_size(parser, bytes);
 116 }
 117
 118 void *yyrealloc(void *ptr, size_t bytes, void *yyscanner)
 119 {
 120         struct grub2_parser *parser = yyget_extra(yyscanner);
 121         return talloc_realloc_size(parser, ptr, bytes);
 122 }
 123
 124 void yyfree(void *ptr, void *yyscanner __attribute__((unused)))
 125 {
 126         talloc_free(ptr);
 127 }