353 lines
10 KiB
Text
353 lines
10 KiB
Text
/* parser.y - The scripting parser. */
|
|
/*
|
|
* GRUB -- GRand Unified Bootloader
|
|
* Copyright (C) 2005,2006,2007,2008,2009,2010 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>
|
|
#include <grub/misc.h>
|
|
|
|
#define YYFREE grub_free
|
|
#define YYMALLOC grub_malloc
|
|
#define YYLTYPE_IS_TRIVIAL 0
|
|
#define YYENABLE_NLS 0
|
|
|
|
#include "grub_script.tab.h"
|
|
%}
|
|
|
|
%union {
|
|
struct grub_script_cmd *cmd;
|
|
struct grub_script_arglist *arglist;
|
|
struct grub_script_arg *arg;
|
|
char *string;
|
|
struct {
|
|
unsigned offset;
|
|
struct grub_script_mem *memory;
|
|
struct grub_script *scripts;
|
|
};
|
|
}
|
|
|
|
%token GRUB_PARSER_TOKEN_BAD
|
|
%token GRUB_PARSER_TOKEN_EOF 0 "end-of-input"
|
|
|
|
%token GRUB_PARSER_TOKEN_NEWLINE "\n"
|
|
%token GRUB_PARSER_TOKEN_AND "&&"
|
|
%token GRUB_PARSER_TOKEN_OR "||"
|
|
%token GRUB_PARSER_TOKEN_SEMI2 ";;"
|
|
%token GRUB_PARSER_TOKEN_PIPE "|"
|
|
%token GRUB_PARSER_TOKEN_AMP "&"
|
|
%token GRUB_PARSER_TOKEN_SEMI ";"
|
|
%token GRUB_PARSER_TOKEN_LBR "{"
|
|
%token GRUB_PARSER_TOKEN_RBR "}"
|
|
%token GRUB_PARSER_TOKEN_NOT "!"
|
|
%token GRUB_PARSER_TOKEN_LSQBR2 "["
|
|
%token GRUB_PARSER_TOKEN_RSQBR2 "]"
|
|
%token GRUB_PARSER_TOKEN_LT "<"
|
|
%token GRUB_PARSER_TOKEN_GT ">"
|
|
|
|
%token <arg> GRUB_PARSER_TOKEN_CASE "case"
|
|
%token <arg> GRUB_PARSER_TOKEN_DO "do"
|
|
%token <arg> GRUB_PARSER_TOKEN_DONE "done"
|
|
%token <arg> GRUB_PARSER_TOKEN_ELIF "elif"
|
|
%token <arg> GRUB_PARSER_TOKEN_ELSE "else"
|
|
%token <arg> GRUB_PARSER_TOKEN_ESAC "esac"
|
|
%token <arg> GRUB_PARSER_TOKEN_FI "fi"
|
|
%token <arg> GRUB_PARSER_TOKEN_FOR "for"
|
|
%token <arg> GRUB_PARSER_TOKEN_IF "if"
|
|
%token <arg> GRUB_PARSER_TOKEN_IN "in"
|
|
%token <arg> GRUB_PARSER_TOKEN_SELECT "select"
|
|
%token <arg> GRUB_PARSER_TOKEN_THEN "then"
|
|
%token <arg> GRUB_PARSER_TOKEN_UNTIL "until"
|
|
%token <arg> GRUB_PARSER_TOKEN_WHILE "while"
|
|
%token <arg> GRUB_PARSER_TOKEN_TIME "time"
|
|
%token <arg> GRUB_PARSER_TOKEN_FUNCTION "function"
|
|
%token <arg> GRUB_PARSER_TOKEN_NAME "name"
|
|
%token <arg> GRUB_PARSER_TOKEN_WORD "word"
|
|
|
|
%type <arg> block block0
|
|
%type <arglist> word argument arguments0 arguments1
|
|
|
|
%type <cmd> script_init script
|
|
%type <cmd> grubcmd ifclause ifcmd forcmd whilecmd untilcmd
|
|
%type <cmd> command commands1 statement
|
|
|
|
%pure-parser
|
|
%lex-param { struct grub_parser_param *state };
|
|
%parse-param { struct grub_parser_param *state };
|
|
|
|
%start script_init
|
|
|
|
%%
|
|
/* It should be possible to do this in a clean way... */
|
|
script_init: { state->err = 0; } script { state->parsed = $2; state->err = 0; }
|
|
;
|
|
|
|
script: newlines0
|
|
{
|
|
$$ = 0;
|
|
}
|
|
| script statement delimiter newlines0
|
|
{
|
|
$$ = grub_script_append_cmd (state, $1, $2);
|
|
}
|
|
| error
|
|
{
|
|
$$ = 0;
|
|
yyerror (state, "Incorrect command");
|
|
yyerrok;
|
|
}
|
|
;
|
|
|
|
newlines0: /* Empty */ | newlines1 ;
|
|
newlines1: newlines0 "\n" ;
|
|
|
|
delimiter: ";"
|
|
| "\n"
|
|
;
|
|
delimiters0: /* Empty */ | delimiters1 ;
|
|
delimiters1: delimiter
|
|
| delimiters1 "\n"
|
|
;
|
|
|
|
word: GRUB_PARSER_TOKEN_NAME { $$ = grub_script_add_arglist (state, 0, $1); }
|
|
| GRUB_PARSER_TOKEN_WORD { $$ = grub_script_add_arglist (state, 0, $1); }
|
|
;
|
|
|
|
statement: command { $$ = $1; }
|
|
| function { $$ = 0; }
|
|
;
|
|
|
|
argument : "case" { $$ = grub_script_add_arglist (state, 0, $1); }
|
|
| "do" { $$ = grub_script_add_arglist (state, 0, $1); }
|
|
| "done" { $$ = grub_script_add_arglist (state, 0, $1); }
|
|
| "elif" { $$ = grub_script_add_arglist (state, 0, $1); }
|
|
| "else" { $$ = grub_script_add_arglist (state, 0, $1); }
|
|
| "esac" { $$ = grub_script_add_arglist (state, 0, $1); }
|
|
| "fi" { $$ = grub_script_add_arglist (state, 0, $1); }
|
|
| "for" { $$ = grub_script_add_arglist (state, 0, $1); }
|
|
| "if" { $$ = grub_script_add_arglist (state, 0, $1); }
|
|
| "in" { $$ = grub_script_add_arglist (state, 0, $1); }
|
|
| "select" { $$ = grub_script_add_arglist (state, 0, $1); }
|
|
| "then" { $$ = grub_script_add_arglist (state, 0, $1); }
|
|
| "until" { $$ = grub_script_add_arglist (state, 0, $1); }
|
|
| "while" { $$ = grub_script_add_arglist (state, 0, $1); }
|
|
| "function" { $$ = grub_script_add_arglist (state, 0, $1); }
|
|
| "time" { $$ = grub_script_add_arglist (state, 0, $1); }
|
|
| word { $$ = $1; }
|
|
;
|
|
|
|
/*
|
|
Block parameter is passed to commands in two forms: as unparsed
|
|
string and as pre-parsed grub_script object. Passing as grub_script
|
|
object makes memory management difficult, because:
|
|
|
|
(1) Command may want to keep a reference to grub_script objects for
|
|
later use, so script framework may not free the grub_script
|
|
object after command completes.
|
|
|
|
(2) Command may get called multiple times with same grub_script
|
|
object under loops, so we should not let command implementation
|
|
to free the grub_script object.
|
|
|
|
To solve above problems, we rely on reference counting for
|
|
grub_script objects. Commands that want to keep the grub_script
|
|
object must take a reference to it.
|
|
|
|
Other complexity comes with arbitrary nesting of grub_script
|
|
objects: a grub_script object may have commands with several block
|
|
parameters, and each block parameter may further contain multiple
|
|
block parameters nested. We use temporary variable, state->scripts
|
|
to collect nested child scripts (that are linked by siblings and
|
|
children members), and will build grub_scripts tree from bottom.
|
|
*/
|
|
block: "{"
|
|
{
|
|
grub_script_lexer_ref (state->lexerstate);
|
|
$<offset>$ = grub_script_lexer_record_start (state);
|
|
$<memory>$ = grub_script_mem_record (state);
|
|
|
|
/* save currently known scripts. */
|
|
$<scripts>$ = state->scripts;
|
|
state->scripts = 0;
|
|
}
|
|
commands1 delimiters0 "}"
|
|
{
|
|
char *p;
|
|
struct grub_script_mem *memory;
|
|
struct grub_script *s = $<scripts>2;
|
|
|
|
memory = grub_script_mem_record_stop (state, $<memory>2);
|
|
if ((p = grub_script_lexer_record_stop (state, $<offset>2)))
|
|
*grub_strrchr (p, '}') = '\0';
|
|
|
|
$$ = grub_script_arg_add (state, 0, GRUB_SCRIPT_ARG_TYPE_BLOCK, p);
|
|
if (! $$ || ! ($$->script = grub_script_create ($3, memory)))
|
|
grub_script_mem_free (memory);
|
|
|
|
else {
|
|
/* attach nested scripts to $$->script as children */
|
|
$$->script->children = state->scripts;
|
|
|
|
/* restore old scripts; append $$->script to siblings. */
|
|
state->scripts = $<scripts>2 ?: $$->script;
|
|
if (s) {
|
|
while (s->next_siblings)
|
|
s = s->next_siblings;
|
|
s->next_siblings = $$->script;
|
|
}
|
|
}
|
|
|
|
grub_script_lexer_deref (state->lexerstate);
|
|
}
|
|
;
|
|
block0: /* Empty */ { $$ = 0; }
|
|
| block { $$ = $1; }
|
|
;
|
|
|
|
arguments0: /* Empty */ { $$ = 0; }
|
|
| arguments1 { $$ = $1; }
|
|
;
|
|
arguments1: argument arguments0
|
|
{
|
|
if ($1 && $2)
|
|
{
|
|
$1->next = $2;
|
|
$1->argcount += $2->argcount;
|
|
$2->argcount = 0;
|
|
}
|
|
$$ = $1;
|
|
}
|
|
;
|
|
|
|
grubcmd: word arguments0 block0
|
|
{
|
|
struct grub_script_arglist *x = $2;
|
|
|
|
if ($3)
|
|
x = grub_script_add_arglist (state, $2, $3);
|
|
|
|
if ($1 && x) {
|
|
$1->next = x;
|
|
$1->argcount += x->argcount;
|
|
x->argcount = 0;
|
|
}
|
|
$$ = grub_script_create_cmdline (state, $1);
|
|
}
|
|
;
|
|
|
|
/* A single command. */
|
|
command: grubcmd { $$ = $1; }
|
|
| ifcmd { $$ = $1; }
|
|
| forcmd { $$ = $1; }
|
|
| whilecmd { $$ = $1; }
|
|
| untilcmd { $$ = $1; }
|
|
;
|
|
|
|
/* A list of commands. */
|
|
commands1: newlines0 command
|
|
{
|
|
$$ = grub_script_append_cmd (state, 0, $2);
|
|
}
|
|
| commands1 delimiters1 command
|
|
{
|
|
$$ = grub_script_append_cmd (state, $1, $3);
|
|
}
|
|
;
|
|
|
|
function: "function" "name"
|
|
{
|
|
grub_script_lexer_ref (state->lexerstate);
|
|
state->func_mem = grub_script_mem_record (state);
|
|
|
|
$<scripts>$ = state->scripts;
|
|
state->scripts = 0;
|
|
}
|
|
delimiters0 "{" commands1 delimiters1 "}"
|
|
{
|
|
struct grub_script *script;
|
|
state->func_mem = grub_script_mem_record_stop (state,
|
|
state->func_mem);
|
|
script = grub_script_create ($6, state->func_mem);
|
|
if (! script)
|
|
grub_script_mem_free (state->func_mem);
|
|
else {
|
|
script->children = state->scripts;
|
|
grub_script_function_create ($2, script);
|
|
}
|
|
|
|
state->scripts = $<scripts>3;
|
|
grub_script_lexer_deref (state->lexerstate);
|
|
}
|
|
;
|
|
|
|
ifcmd: "if"
|
|
{
|
|
grub_script_lexer_ref (state->lexerstate);
|
|
}
|
|
ifclause "fi"
|
|
{
|
|
$$ = $3;
|
|
grub_script_lexer_deref (state->lexerstate);
|
|
}
|
|
;
|
|
ifclause: commands1 delimiters1 "then" commands1 delimiters1
|
|
{
|
|
$$ = grub_script_create_cmdif (state, $1, $4, 0);
|
|
}
|
|
| commands1 delimiters1 "then" commands1 delimiters1 "else" commands1 delimiters1
|
|
{
|
|
$$ = grub_script_create_cmdif (state, $1, $4, $7);
|
|
}
|
|
| commands1 delimiters1 "then" commands1 delimiters1 "elif" ifclause
|
|
{
|
|
$$ = grub_script_create_cmdif (state, $1, $4, $7);
|
|
}
|
|
;
|
|
|
|
forcmd: "for" "name"
|
|
{
|
|
grub_script_lexer_ref (state->lexerstate);
|
|
}
|
|
"in" arguments0 delimiters1 "do" commands1 delimiters1 "done"
|
|
{
|
|
$$ = grub_script_create_cmdfor (state, $2, $5, $8);
|
|
grub_script_lexer_deref (state->lexerstate);
|
|
}
|
|
;
|
|
|
|
whilecmd: "while"
|
|
{
|
|
grub_script_lexer_ref (state->lexerstate);
|
|
}
|
|
commands1 delimiters1 "do" commands1 delimiters1 "done"
|
|
{
|
|
$$ = grub_script_create_cmdwhile (state, $3, $6, 0);
|
|
grub_script_lexer_deref (state->lexerstate);
|
|
}
|
|
;
|
|
|
|
untilcmd: "until"
|
|
{
|
|
grub_script_lexer_ref (state->lexerstate);
|
|
}
|
|
commands1 delimiters1 "do" commands1 delimiters1 "done"
|
|
{
|
|
$$ = grub_script_create_cmdwhile (state, $3, $6, 1);
|
|
grub_script_lexer_deref (state->lexerstate);
|
|
}
|
|
;
|