grub/script/parser.y
Robert Millan f515aa6224 2009-11-23 Robert Millan <rmh.grub@aybabtu.com>
* script/sh/execute.c: Move from here ...
        * script/execute.c: ... to here.  Update all users.
        * script/sh/function.c: Move from here ...
        * script/function.c: ... to here.  Update all users.
        * script/sh/lexer.c: Move from here ...
        * script/lexer.c: ... to here.  Update all users.
        * script/sh/main.c: Move from here ...
        * script/main.c: ... to here.  Update all users.
        * script/sh/parser.y: Move from here ...
        * script/parser.y: ... to here.  Update all users.
        * script/sh/script.c: Move from here ...
        * script/script.c: ... to here.  Update all users.
2009-11-23 15:37:33 +00:00

197 lines
5.3 KiB
Text

/* parser.y - The scripting parser. */
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2005,2006,2007,2008,2009 Free Software Foundation, Inc.
*
* GRUB is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* GRUB is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GRUB. If not, see <http://www.gnu.org/licenses/>.
*/
%{
#include <grub/script_sh.h>
#include <grub/mm.h>
#define YYFREE grub_free
#define YYMALLOC grub_malloc
#define YYLTYPE_IS_TRIVIAL 0
#define YYENABLE_NLS 0
%}
%union {
struct grub_script_cmd *cmd;
struct grub_script_arglist *arglist;
struct grub_script_arg *arg;
char *string;
}
%token GRUB_PARSER_TOKEN_IF "if"
%token GRUB_PARSER_TOKEN_WHILE "while"
%token GRUB_PARSER_TOKEN_FUNCTION "function"
%token GRUB_PARSER_TOKEN_MENUENTRY "menuentry"
%token GRUB_PARSER_TOKEN_ELSE "else"
%token GRUB_PARSER_TOKEN_THEN "then"
%token GRUB_PARSER_TOKEN_FI "fi"
%token GRUB_PARSER_TOKEN_ARG
%type <cmd> script_init script grubcmd command commands commandblock menuentry if
%type <arglist> arguments;
%type <arg> GRUB_PARSER_TOKEN_ARG;
%pure-parser
%lex-param { struct grub_parser_param *state };
%parse-param { struct grub_parser_param *state };
%%
/* It should be possible to do this in a clean way... */
script_init: { state->err = 0; } script
{
state->parsed = $2;
}
;
script: { $$ = 0; }
| '\n' { $$ = 0; }
| commands { $$ = $1; }
| function '\n' { $$ = 0; }
| menuentry '\n' { $$ = $1; }
| error
{
$$ = 0;
yyerror (state, "Incorrect command");
state->err = 1;
yyerrok;
}
;
delimiter: '\n'
| ';'
| delimiter '\n'
;
newlines: /* Empty */
| newlines '\n'
;
arguments: GRUB_PARSER_TOKEN_ARG
{
$$ = grub_script_add_arglist (state, 0, $1);
}
| arguments GRUB_PARSER_TOKEN_ARG
{
$$ = grub_script_add_arglist (state, $1, $2);
}
;
grubcmd: arguments
{
$$ = grub_script_create_cmdline (state, $1);
}
;
/* A single command. */
command: grubcmd delimiter { $$ = $1; }
| if delimiter { $$ = $1; }
| commandblock delimiter { $$ = $1; }
;
/* A block of commands. */
commands: command
{
$$ = grub_script_add_cmd (state, 0, $1);
}
| command commands
{
struct grub_script_cmdblock *cmd;
cmd = (struct grub_script_cmdblock *) $2;
$$ = grub_script_add_cmd (state, cmd, $1);
}
;
/* A function. Carefully save the memory that is allocated. Don't
change any stuff because it might seem like a fun thing to do!
Special care was take to make sure the mid-rule actions are
executed on the right moment. So the `commands' rule should be
recognized after executing the `grub_script_mem_record; and before
`grub_script_mem_record_stop'. */
function: "function" GRUB_PARSER_TOKEN_ARG
{
grub_script_lexer_ref (state->lexerstate);
} newlines '{'
{
/* The first part of the function was recognized.
Now start recording the memory usage to store
this function. */
state->func_mem = grub_script_mem_record (state);
} newlines commands '}'
{
struct grub_script *script;
/* All the memory usage for parsing this function
was recorded. */
state->func_mem = grub_script_mem_record_stop (state,
state->func_mem);
script = grub_script_create ($8, state->func_mem);
if (script)
grub_script_function_create ($2, script);
grub_script_lexer_deref (state->lexerstate);
}
;
/* Carefully designed, together with `menuentry' so everything happens
just in the expected order. */
commandblock: '{'
{
grub_script_lexer_ref (state->lexerstate);
}
newlines commands '}'
{
grub_script_lexer_deref (state->lexerstate);
$$ = $4;
}
;
/* A menu entry. Carefully save the memory that is allocated. */
menuentry: "menuentry"
{
grub_script_lexer_ref (state->lexerstate);
} arguments newlines '{'
{
grub_script_lexer_record_start (state->lexerstate);
} newlines commands '}'
{
char *menu_entry;
menu_entry = grub_script_lexer_record_stop (state->lexerstate);
grub_script_lexer_deref (state->lexerstate);
$$ = grub_script_create_cmdmenu (state, $3, menu_entry, 0);
}
;
/* The first part of the if statement. It's used to switch the lexer
to a state in which it demands more tokens. */
if_statement: "if" { grub_script_lexer_ref (state->lexerstate); }
;
/* The if statement. */
if: if_statement commands "then" newlines commands "fi"
{
$$ = grub_script_create_cmdif (state, $2, $5, 0);
grub_script_lexer_deref (state->lexerstate);
}
| if_statement commands "then" newlines commands "else" newlines commands "fi"
{
$$ = grub_script_create_cmdif (state, $2, $5, $8);
grub_script_lexer_deref (state->lexerstate);
}
;