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 void yyerror(struct grub2_parser *parser, const char *fmt, ...);
   8 %}
   9
  10 %option nounput noinput
  11 %option batch never-interactive
  12 %option warn
  13 %option noyywrap
  14 %option stack noyy_top_state
  15 %option reentrant
  16 %option bison-bridge
  17 %option yylineno
  18 %option noyyalloc noyyfree noyyrealloc
  19 %option extra-type="struct grub2_parser *"
  20 %option header-file="lexer.h"
  21 %option outfile="lexer.c"
  22
  23 %x sqstring
  24 %x dqstring
  25
  26 WORD    [^{}|&$;<> \t\n'"#]+
  27 VARNAME ([[:alpha:]][_[:alnum:]]*|[0-9]|[\?@\*#])
  28
  29 %%
  30
  31  /* discard leading & trailing whitespace, but keep inter-word delimeters */
  32 ^[ \t]+ ;
  33 [ \t]+$ ;
  34 [ \t]+  return TOKEN_DELIM;
  35
  36  /* reserved words */
  37 "[["         return TOKEN_LDSQBRACKET;
  38 "]]"         return TOKEN_RDSQBRACKET;
  39 "case"       return TOKEN_CASE;
  40 "do"         return TOKEN_DO;
  41 "done"       return TOKEN_DONE;
  42 "elif"       return TOKEN_ELIF;
  43 "else"       return TOKEN_ELSE;
  44 "esac"       return TOKEN_ESAC;
  45 "fi"         return TOKEN_FI;
  46 "for"        return TOKEN_FOR;
  47 "function"   return TOKEN_FUNCTION;
  48 "if"         return TOKEN_IF;
  49 "in"         return TOKEN_IN;
  50 "menuentry"  return TOKEN_MENUENTRY;
  51 "select"     return TOKEN_SELECT;
  52 "submenu"    return TOKEN_SUBMENU;
  53 "then"       return TOKEN_THEN;
  54 "time"       return TOKEN_TIME;
  55 "until"      return TOKEN_UTIL;
  56 "while"      return TOKEN_WHILE;
  57
  58  /* anything that's not a metachar: return as a plain word */
  59 {WORD}  {
  60                 yylval->word = create_word_text(yyget_extra(yyscanner), yytext);
  61                 return TOKEN_WORD;
  62         }
  63
  64 \${VARNAME} |
  65 \$\{{VARNAME}\} {
  66                 if (yytext[1] == '{') {
  67                         yytext[yyleng-1] = '\0';
  68                         yytext++;
  69                 }
  70                 yytext++;
  71                 yylval->word = create_word_var(yyget_extra(yyscanner), yytext,
  72                                                 true);
  73                 return TOKEN_WORD;
  74         }
  75
  76  /* single-quoted strings: return a single, non-expanded word token */
  77 \'      {
  78                 yy_push_state(sqstring, yyscanner);
  79         }
  80 <sqstring>\' {
  81                 yy_pop_state(yyscanner);
  82         }
  83 <sqstring>[^']+ {
  84                 yylval->word = create_word_text(yyget_extra(yyscanner), yytext);
  85                 return TOKEN_WORD;
  86         }
  87
  88  /* double-quoted strings: return a single, expanded word token */
  89 \"      {
  90                 yy_push_state(dqstring, yyscanner);
  91         }
  92 <dqstring>\" {
  93                 yy_pop_state(yyscanner);
  94         }
  95 <dqstring>([^"\$]|\\\")+ {
  96                 yylval->word = create_word_text(yyget_extra(yyscanner), yytext);
  97                 return TOKEN_WORD;
  98         }
  99 <dqstring>\${VARNAME} |
 100 <dqstring>\$\{{VARNAME}\} {
 101                 if (yytext[1] == '{') {
 102                         yytext[yyleng-1] = '\0';
 103                         yytext++;
 104                 }
 105                 yytext++;
 106                 yylval->word = create_word_var(yyget_extra(yyscanner), yytext,
 107                                                 false);
 108                 return TOKEN_WORD;
 109         }
 110
 111
 112
 113  /* blocks */
 114 "{"     return '{';
 115 "}"     return '}';
 116
 117  /* end-of-line */
 118 [ \t]*(;|\n)[ \t]*      return TOKEN_EOL;
 119
 120  /* strip comments */
 121 #.*     ;
 122
 123 .       {
 124                 yyerror(yyget_extra(yyscanner), "unknown token '%s'\n", yytext);
 125                 yyterminate();
 126         }
 127
 128 %%
 129
 130 struct grub2_parser;
 131
 132 void *yyalloc(size_t bytes, void *yyscanner)
 133 {
 134         struct grub2_parser *parser = yyget_extra(yyscanner);
 135         return talloc_size(parser, bytes);
 136 }
 137
 138 void *yyrealloc(void *ptr, size_t bytes, void *yyscanner)
 139 {
 140         struct grub2_parser *parser = yyget_extra(yyscanner);
 141         return talloc_realloc_size(parser, ptr, bytes);
 142 }
 143
 144 void yyfree(void *ptr, void *yyscanner __attribute__((unused)))
 145 {
 146         talloc_free(ptr);
 147 }