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 noyyalloc noyyfree noyyrealloc
  16 %option extra-type="struct grub2_parser *"
  17 %option header-file="lexer.h"
  18 %option outfile="lexer.c"
  19
  20 %x sqstring
  21 %x dqstring
  22
  23 WORD    [^{}|&$;<> \t\n'"]+
  24 VARNAME ([[:alpha:]][_[:alnum:]]*|[0-9]|[\?@\*#])
  25
  26 %%
  27
  28  /* discard leading & trailing whitespace, but keep inter-word delimeters */
  29 ^[ \t]+ ;
  30 [ \t]+$ ;
  31 [ \t]*  return TOKEN_DELIM;
  32
  33  /* reserved words */
  34 "[["         return TOKEN_LDSQBRACKET;
  35 "]]"         return TOKEN_RDSQBRACKET;
  36 "case"       return TOKEN_CASE;
  37 "do"         return TOKEN_DO;
  38 "done"       return TOKEN_DONE;
  39 "elif"       return TOKEN_ELIF;
  40 "esac"       return TOKEN_ESAC;
  41 "fi"         return TOKEN_FI;
  42 "for"        return TOKEN_FOR;
  43 "function"   return TOKEN_FUNCTION;
  44 "if"         return TOKEN_IF;
  45 "in"         return TOKEN_IN;
  46 "menuentry"  return TOKEN_MENUENTRY;
  47 "select"     return TOKEN_SELECT;
  48 "then"       return TOKEN_THEN;
  49 "time"       return TOKEN_TIME;
  50 "until"      return TOKEN_UTIL;
  51 "while"      return TOKEN_WHILE;
  52
  53  /* anything that's not a metachar: return as a plain word */
  54 {WORD}  {
  55                 yylval->word = create_word_text(yyget_extra(yyscanner), yytext);
  56                 return TOKEN_WORD;
  57         }
  58
  59 \${VARNAME} |
  60 \$\{{VARNAME}\} {
  61                 if (yytext[1] == '{') {
  62                         yytext[yyleng-1] = '\0';
  63                         yytext++;
  64                 }
  65                 yytext++;
  66                 yylval->word = create_word_var(yyget_extra(yyscanner), yytext,
  67                                                 true);
  68                 return TOKEN_WORD;
  69         }
  70
  71  /* single-quoted strings: return a single, non-expanded word token */
  72 \'      {
  73                 yy_push_state(sqstring, yyscanner);
  74         }
  75 <sqstring>\' {
  76                 yy_pop_state(yyscanner);
  77         }
  78 <sqstring>[^']+ {
  79                 yylval->word = create_word_text(yyget_extra(yyscanner), yytext);
  80                 return TOKEN_WORD;
  81         }
  82
  83  /* double-quoted strings: return a single, expanded word token */
  84 \"      {
  85                 yy_push_state(dqstring, yyscanner);
  86         }
  87 <dqstring>\" {
  88                 yy_pop_state(yyscanner);
  89         }
  90 <dqstring>([^"\$]|\\\")+ {
  91                 yylval->word = create_word_text(yyget_extra(yyscanner), yytext);
  92                 return TOKEN_WORD;
  93         }
  94 <dqstring>\${VARNAME} |
  95 <dqstring>\$\{{VARNAME}\} {
  96                 if (yytext[1] == '{') {
  97                         yytext[yyleng-1] = '\0';
  98                         yytext++;
  99                 }
 100                 yytext++;
 101                 yylval->word = create_word_var(yyget_extra(yyscanner), yytext,
 102                                                 false);
 103                 return TOKEN_WORD;
 104         }
 105
 106
 107
 108  /* blocks */
 109 "{"     return '{';
 110 "}"     return '}';
 111
 112  /* end-of-line */
 113 [ \t]*(;|\n)[ \t]*      return TOKEN_EOL;
 114
 115  /* strip comments */
 116 #.*$    ;
 117
 118
 119 .       printf("unknown token '%s'\n", yytext); exit(1);
 120
 121 %%
 122
 123 struct grub2_parser;
 124
 125 void *yyalloc(size_t bytes, void *yyscanner)
 126 {
 127         struct grub2_parser *parser = yyget_extra(yyscanner);
 128         return talloc_size(parser, bytes);
 129 }
 130
 131 void *yyrealloc(void *ptr, size_t bytes, void *yyscanner)
 132 {
 133         struct grub2_parser *parser = yyget_extra(yyscanner);
 134         return talloc_realloc_size(parser, ptr, bytes);
 135 }
 136
 137 void yyfree(void *ptr, void *yyscanner __attribute__((unused)))
 138 {
 139         talloc_free(ptr);
 140 }