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

   1
   2 %{
   3 #include "grub2.h"
   4 #include "parser.h"
   5 #include <talloc/talloc.h>
   6 %}
   7
   8 %option nounput noinput
   9 %option warn
  10 %option noyywrap
  11 %option stack noyy_top_state
  12 %option reentrant
  13 %option bison-bridge
  14 %option noyyalloc noyyfree noyyrealloc
  15 %option extra-type="struct grub2_parser *"
  16 %option header-file="lexer.h"
  17 %option outfile="lexer.c"
  18
  19 %x sqstring
  20 %x dqstring
  21
  22 WORD    [^{}|&$;<> \t\n'"]+
  23 VARNAME ([[:alpha:]][_[:alnum:]]*|[0-9]|[\?@\*#])
  24
  25 %%
  26
  27  /* discard leading & trailing whitespace, but keep inter-word delimeters */
  28 ^[ \t]+ ;
  29 [ \t]+$ ;
  30 [ \t]*  return TOKEN_DELIM;
  31
  32  /* reserved words */
  33 "[["         return TOKEN_LDSQBRACKET;
  34 "]]"         return TOKEN_RDSQBRACKET;
  35 "case"       return TOKEN_CASE;
  36 "do"         return TOKEN_DO;
  37 "done"       return TOKEN_DONE;
  38 "elif"       return TOKEN_ELIF;
  39 "esac"       return TOKEN_ESAC;
  40 "fi"         return TOKEN_FI;
  41 "for"        return TOKEN_FOR;
  42 "function"   return TOKEN_FUNCTION;
  43 "if"         return TOKEN_IF;
  44 "in"         return TOKEN_IN;
  45 "menuentry"  return TOKEN_MENUENTRY;
  46 "select"     return TOKEN_SELECT;
  47 "then"       return TOKEN_THEN;
  48 "time"       return TOKEN_TIME;
  49 "until"      return TOKEN_UTIL;
  50 "while"      return TOKEN_WHILE;
  51
  52  /* anything that's not a metachar: return as a plain word */
  53 {WORD}  {
  54                 yylval->word = create_word(yyget_extra(yyscanner), yytext,
  55                                                 false, false);
  56                 return TOKEN_WORD;
  57         }
  58
  59 \${VARNAME} |
  60 \$\{{VARNAME}\} {
  61                 yylval->word = create_word(yyget_extra(yyscanner), yytext,
  62                                                 true, true);
  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         }
  73 <sqstring>[^']+ {
  74                 yylval->word = create_word(yyget_extra(yyscanner), yytext,
  75                                                 false, false);
  76                 return TOKEN_WORD;
  77         }
  78
  79  /* double-quoted strings: return a single, expanded word token */
  80 \"      {
  81                 yy_push_state(dqstring, yyscanner);
  82         }
  83 <dqstring>\" {
  84                 yy_pop_state(yyscanner);
  85         }
  86 <dqstring>([^"]|\\\")+ {
  87                 yylval->word = create_word(yyget_extra(yyscanner), yytext,
  88                                                 true, false);
  89                 return TOKEN_WORD;
  90         }
  91
  92
  93  /* blocks */
  94 "{"     return '{';
  95 "}"     return '}';
  96
  97  /* end-of-line */
  98 [ \t]*(;|\n)[ \t]*      return TOKEN_EOL;
  99
 100  /* strip comments */
 101 #.*$    ;
 102
 103
 104 .       printf("unknown token '%s'\n", yytext); exit(1);
 105
 106 %%
 107
 108 struct grub2_parser;
 109
 110 void *yyalloc(size_t bytes, void *yyscanner)
 111 {
 112         struct grub2_parser *parser = yyget_extra(yyscanner);
 113         return talloc_size(parser, bytes);
 114 }
 115
 116 void *yyrealloc(void *ptr, size_t bytes, void *yyscanner)
 117 {
 118         struct grub2_parser *parser = yyget_extra(yyscanner);
 119         return talloc_realloc_size(parser, ptr, bytes);
 120 }
 121
 122 void yyfree(void *ptr, void *yyscanner __attribute__((unused)))
 123 {
 124         talloc_free(ptr);
 125 }