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 batch never-interactive
  10 %option warn
  11 %option noyywrap
  12 %option stack noyy_top_state
  13 %option reentrant
  14 %option bison-bridge
  15 %option yylineno
  16 %option noyyalloc noyyfree noyyrealloc
  17 %option extra-type="struct grub2_parser *"
  18 %option header-file="lexer.h"
  19 %option outfile="lexer.c"
  20
  21 %x sqstring
  22 %x dqstring
  23
  24 WORD    [^{}|&$;<> \t\n'"]+
  25 VARNAME ([[:alpha:]][_[:alnum:]]*|[0-9]|[\?@\*#])
  26
  27 %%
  28
  29  /* discard leading & trailing whitespace, but keep inter-word delimeters */
  30 ^[ \t]+ ;
  31 [ \t]+$ ;
  32 [ \t]*  return TOKEN_DELIM;
  33
  34  /* reserved words */
  35 "[["         return TOKEN_LDSQBRACKET;
  36 "]]"         return TOKEN_RDSQBRACKET;
  37 "case"       return TOKEN_CASE;
  38 "do"         return TOKEN_DO;
  39 "done"       return TOKEN_DONE;
  40 "elif"       return TOKEN_ELIF;
  41 "else"       return TOKEN_ELSE;
  42 "esac"       return TOKEN_ESAC;
  43 "fi"         return TOKEN_FI;
  44 "for"        return TOKEN_FOR;
  45 "function"   return TOKEN_FUNCTION;
  46 "if"         return TOKEN_IF;
  47 "in"         return TOKEN_IN;
  48 "menuentry"  return TOKEN_MENUENTRY;
  49 "select"     return TOKEN_SELECT;
  50 "then"       return TOKEN_THEN;
  51 "time"       return TOKEN_TIME;
  52 "until"      return TOKEN_UTIL;
  53 "while"      return TOKEN_WHILE;
  54
  55  /* anything that's not a metachar: return as a plain word */
  56 {WORD}  {
  57                 yylval->word = create_word_text(yyget_extra(yyscanner), yytext);
  58                 return TOKEN_WORD;
  59         }
  60
  61 \${VARNAME} |
  62 \$\{{VARNAME}\} {
  63                 if (yytext[1] == '{') {
  64                         yytext[yyleng-1] = '\0';
  65                         yytext++;
  66                 }
  67                 yytext++;
  68                 yylval->word = create_word_var(yyget_extra(yyscanner), yytext,
  69                                                 true);
  70                 return TOKEN_WORD;
  71         }
  72
  73  /* single-quoted strings: return a single, non-expanded word token */
  74 \'      {
  75                 yy_push_state(sqstring, yyscanner);
  76         }
  77 <sqstring>\' {
  78                 yy_pop_state(yyscanner);
  79         }
  80 <sqstring>[^']+ {
  81                 yylval->word = create_word_text(yyget_extra(yyscanner), yytext);
  82                 return TOKEN_WORD;
  83         }
  84
  85  /* double-quoted strings: return a single, expanded word token */
  86 \"      {
  87                 yy_push_state(dqstring, yyscanner);
  88         }
  89 <dqstring>\" {
  90                 yy_pop_state(yyscanner);
  91         }
  92 <dqstring>([^"\$]|\\\")+ {
  93                 yylval->word = create_word_text(yyget_extra(yyscanner), yytext);
  94                 return TOKEN_WORD;
  95         }
  96 <dqstring>\${VARNAME} |
  97 <dqstring>\$\{{VARNAME}\} {
  98                 if (yytext[1] == '{') {
  99                         yytext[yyleng-1] = '\0';
 100                         yytext++;
 101                 }
 102                 yytext++;
 103                 yylval->word = create_word_var(yyget_extra(yyscanner), yytext,
 104                                                 false);
 105                 return TOKEN_WORD;
 106         }
 107
 108
 109
 110  /* blocks */
 111 "{"     return '{';
 112 "}"     return '}';
 113
 114  /* end-of-line */
 115 [ \t]*(;|\n)[ \t]*      return TOKEN_EOL;
 116
 117  /* strip comments */
 118 #.*$    ;
 119
 120
 121 .       printf("unknown token '%s'\n", yytext); exit(1);
 122
 123 %%
 124
 125 struct grub2_parser;
 126
 127 void *yyalloc(size_t bytes, void *yyscanner)
 128 {
 129         struct grub2_parser *parser = yyget_extra(yyscanner);
 130         return talloc_size(parser, bytes);
 131 }
 132
 133 void *yyrealloc(void *ptr, size_t bytes, void *yyscanner)
 134 {
 135         struct grub2_parser *parser = yyget_extra(yyscanner);
 136         return talloc_realloc_size(parser, ptr, bytes);
 137 }
 138
 139 void yyfree(void *ptr, void *yyscanner __attribute__((unused)))
 140 {
 141         talloc_free(ptr);
 142 }