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 "else"       return TOKEN_ELSE;
  41 "esac"       return TOKEN_ESAC;
  42 "fi"         return TOKEN_FI;
  43 "for"        return TOKEN_FOR;
  44 "function"   return TOKEN_FUNCTION;
  45 "if"         return TOKEN_IF;
  46 "in"         return TOKEN_IN;
  47 "menuentry"  return TOKEN_MENUENTRY;
  48 "select"     return TOKEN_SELECT;
  49 "then"       return TOKEN_THEN;
  50 "time"       return TOKEN_TIME;
  51 "until"      return TOKEN_UTIL;
  52 "while"      return TOKEN_WHILE;
  53
  54  /* anything that's not a metachar: return as a plain word */
  55 {WORD}  {
  56                 yylval->word = create_word_text(yyget_extra(yyscanner), yytext);
  57                 return TOKEN_WORD;
  58         }
  59
  60 \${VARNAME} |
  61 \$\{{VARNAME}\} {
  62                 if (yytext[1] == '{') {
  63                         yytext[yyleng-1] = '\0';
  64                         yytext++;
  65                 }
  66                 yytext++;
  67                 yylval->word = create_word_var(yyget_extra(yyscanner), yytext,
  68                                                 true);
  69                 return TOKEN_WORD;
  70         }
  71
  72  /* single-quoted strings: return a single, non-expanded word token */
  73 \'      {
  74                 yy_push_state(sqstring, yyscanner);
  75         }
  76 <sqstring>\' {
  77                 yy_pop_state(yyscanner);
  78         }
  79 <sqstring>[^']+ {
  80                 yylval->word = create_word_text(yyget_extra(yyscanner), yytext);
  81                 return TOKEN_WORD;
  82         }
  83
  84  /* double-quoted strings: return a single, expanded word token */
  85 \"      {
  86                 yy_push_state(dqstring, yyscanner);
  87         }
  88 <dqstring>\" {
  89                 yy_pop_state(yyscanner);
  90         }
  91 <dqstring>([^"\$]|\\\")+ {
  92                 yylval->word = create_word_text(yyget_extra(yyscanner), yytext);
  93                 return TOKEN_WORD;
  94         }
  95 <dqstring>\${VARNAME} |
  96 <dqstring>\$\{{VARNAME}\} {
  97                 if (yytext[1] == '{') {
  98                         yytext[yyleng-1] = '\0';
  99                         yytext++;
 100                 }
 101                 yytext++;
 102                 yylval->word = create_word_var(yyget_extra(yyscanner), yytext,
 103                                                 false);
 104                 return TOKEN_WORD;
 105         }
 106
 107
 108
 109  /* blocks */
 110 "{"     return '{';
 111 "}"     return '}';
 112
 113  /* end-of-line */
 114 [ \t]*(;|\n)[ \t]*      return TOKEN_EOL;
 115
 116  /* strip comments */
 117 #.*$    ;
 118
 119
 120 .       printf("unknown token '%s'\n", yytext); exit(1);
 121
 122 %%
 123
 124 struct grub2_parser;
 125
 126 void *yyalloc(size_t bytes, void *yyscanner)
 127 {
 128         struct grub2_parser *parser = yyget_extra(yyscanner);
 129         return talloc_size(parser, bytes);
 130 }
 131
 132 void *yyrealloc(void *ptr, size_t bytes, void *yyscanner)
 133 {
 134         struct grub2_parser *parser = yyget_extra(yyscanner);
 135         return talloc_realloc_size(parser, ptr, bytes);
 136 }
 137
 138 void yyfree(void *ptr, void *yyscanner __attribute__((unused)))
 139 {
 140         talloc_free(ptr);
 141 }