grub/script/sh/lexer.c
phcoder 48e40bff44 2009-08-24 Vladimir Serbinenko <phcoder@gmail.com>
* script/sh/function.c (grub_script_function_find): Cut error message
	not to flood terminal.
	* script/sh/lexer.c (grub_script_yylex): Remove command line length
	limit.
	* script/sh/script.c (grub_script_arg_add): Duplicate string.
2009-08-24 19:08:11 +00:00

433 lines
11 KiB
C

/* lexer.c - The scripting lexer. */
/*
* 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/parser.h>
#include <grub/misc.h>
#include <grub/mm.h>
#include <grub/script_sh.h>
#include "grub_script.tab.h"
static int
check_varstate (grub_parser_state_t state)
{
return (state == GRUB_PARSER_STATE_VARNAME
|| state == GRUB_PARSER_STATE_VAR
|| state == GRUB_PARSER_STATE_QVAR
|| state == GRUB_PARSER_STATE_VARNAME2
|| state == GRUB_PARSER_STATE_QVARNAME
|| state == GRUB_PARSER_STATE_QVARNAME2);
}
static int
check_textstate (grub_parser_state_t state)
{
return (state == GRUB_PARSER_STATE_TEXT
|| state == GRUB_PARSER_STATE_ESC
|| state == GRUB_PARSER_STATE_QUOTE
|| state == GRUB_PARSER_STATE_DQUOTE);
}
struct grub_lexer_param *
grub_script_lexer_init (char *script, grub_reader_getline_t getline)
{
struct grub_lexer_param *param;
param = grub_zalloc (sizeof (*param));
if (! param)
return 0;
param->state = GRUB_PARSER_STATE_TEXT;
param->getline = getline;
param->script = script;
return param;
}
void
grub_script_lexer_ref (struct grub_lexer_param *state)
{
state->refs++;
}
void
grub_script_lexer_deref (struct grub_lexer_param *state)
{
state->refs--;
}
/* Start recording all characters passing through the lexer. */
void
grub_script_lexer_record_start (struct grub_lexer_param *state)
{
state->record = 1;
state->recordlen = 100;
state->recording = grub_malloc (state->recordlen);
state->recordpos = 0;
}
char *
grub_script_lexer_record_stop (struct grub_lexer_param *state)
{
state->record = 0;
/* Delete the last character, it is a `}'. */
if (state->recordpos > 0)
{
if (state->recording[--state->recordpos] != '}')
{
grub_printf ("Internal error while parsing menu entry");
for (;;); /* XXX */
}
state->recording[state->recordpos] = '\0';
}
return state->recording;
}
/* When recording is enabled, record the character C as the next item
in the character stream. */
static void
recordchar (struct grub_lexer_param *state, char c)
{
if (state->recordpos == state->recordlen)
{
char *old = state->recording;
state->recordlen += 100;
state->recording = grub_realloc (state->recording, state->recordlen);
if (! state->recording)
{
grub_free (old);
state->record = 0;
}
}
state->recording[state->recordpos++] = c;
}
/* Fetch the next character for the lexer. */
static void
nextchar (struct grub_lexer_param *state)
{
if (state->record)
recordchar (state, *state->script);
state->script++;
}
int
grub_script_yylex (union YYSTYPE *yylval, struct grub_parser_param *parsestate)
{
grub_parser_state_t newstate;
char use;
struct grub_lexer_param *state = parsestate->lexerstate;
int firstrun = 1;
yylval->arg = 0;
if (state->tokenonhold)
{
int token = state->tokenonhold;
state->tokenonhold = 0;
return token;
}
for (;! state->done; firstrun = 0)
{
if (! state->script || ! *state->script)
{
/* Check if more tokens are requested by the parser. */
if (((state->refs && ! parsestate->err)
|| state->state == GRUB_PARSER_STATE_ESC
|| state->state == GRUB_PARSER_STATE_QUOTE
|| state->state == GRUB_PARSER_STATE_DQUOTE)
&& state->getline)
{
int doexit = 0;
if (state->state != GRUB_PARSER_STATE_ESC
&& state->state != GRUB_PARSER_STATE_QUOTE
&& state->state != GRUB_PARSER_STATE_DQUOTE
&& ! state->was_newline)
{
state->was_newline = 1;
state->tokenonhold = '\n';
break;
}
while (! state->script || ! *state->script)
{
grub_free (state->newscript);
state->newscript = 0;
state->getline (&state->newscript, 1);
state->script = state->newscript;
if (! state->script)
{
doexit = 1;
break;
}
}
if (doexit)
break;
grub_dprintf ("scripting", "token=`\\n'\n");
recordchar (state, '\n');
if (state->state == GRUB_PARSER_STATE_VARNAME)
state->state = GRUB_PARSER_STATE_TEXT;
if (state->state == GRUB_PARSER_STATE_QVARNAME)
state->state = GRUB_PARSER_STATE_DQUOTE;
if (state->state == GRUB_PARSER_STATE_DQUOTE
|| state->state == GRUB_PARSER_STATE_QUOTE)
yylval->arg = grub_script_arg_add (parsestate, yylval->arg,
GRUB_SCRIPT_ARG_TYPE_STR,
"\n");
}
else
{
grub_free (state->newscript);
state->newscript = 0;
state->done = 1;
grub_dprintf ("scripting", "token=`\\n'\n");
state->tokenonhold = '\n';
break;
}
}
state->was_newline = 0;
newstate = grub_parser_cmdline_state (state->state, *state->script, &use);
/* Check if it is a text. */
if (check_textstate (newstate))
{
char *buffer = NULL;
int bufpos = 0;
/* Buffer is initially large enough to hold most commands
but extends automatically when needed. */
int bufsize = 128;
buffer = grub_malloc (bufsize);
/* In case the string is not quoted, this can be a one char
length symbol. */
if (newstate == GRUB_PARSER_STATE_TEXT)
{
int doexit = 0;
switch (*state->script)
{
case ' ':
while (*state->script)
{
newstate = grub_parser_cmdline_state (state->state,
*state->script, &use);
if (! (state->state == GRUB_PARSER_STATE_TEXT
&& *state->script == ' '))
{
grub_dprintf ("scripting", "token=` '\n");
if (! firstrun)
doexit = 1;
break;
}
state->state = newstate;
nextchar (state);
}
grub_dprintf ("scripting", "token=` '\n");
if (! firstrun)
doexit = 1;
break;
case '{':
case '}':
case ';':
case '\n':
{
char c;
grub_dprintf ("scripting", "token=`%c'\n", *state->script);
c = *state->script;
nextchar (state);
state->tokenonhold = c;
doexit = 1;
break;
}
}
if (doexit)
{
grub_free (buffer);
break;
}
}
/* Read one token, possible quoted. */
while (*state->script)
{
newstate = grub_parser_cmdline_state (state->state,
*state->script, &use);
/* Check if a variable name starts. */
if (check_varstate (newstate))
break;
/* If the string is not quoted or escaped, stop processing
when a special token was found. It will be recognized
next time when this function is called. */
if (newstate == GRUB_PARSER_STATE_TEXT
&& state->state != GRUB_PARSER_STATE_ESC
&& state->state != GRUB_PARSER_STATE_QUOTE
&& state->state != GRUB_PARSER_STATE_DQUOTE)
{
int breakout = 0;
switch (use)
{
case ' ':
case '{':
case '}':
case ';':
case '\n':
breakout = 1;
}
if (breakout)
break;
}
if (use)
{
if (bufsize <= bufpos + 1)
{
bufsize <<= 1;
buffer = grub_realloc (buffer, bufsize);
}
buffer[bufpos++] = use;
}
state->state = newstate;
nextchar (state);
}
/* A string of text was read in. */
if (bufsize <= bufpos + 1)
{
bufsize <<= 1;
buffer = grub_realloc (buffer, bufsize);
}
buffer[bufpos++] = 0;
grub_dprintf ("scripting", "token=`%s'\n", buffer);
yylval->arg = grub_script_arg_add (parsestate, yylval->arg,
GRUB_SCRIPT_ARG_TYPE_STR, buffer);
grub_free (buffer);
}
else if (newstate == GRUB_PARSER_STATE_VAR
|| newstate == GRUB_PARSER_STATE_QVAR)
{
char *buffer = NULL;
int bufpos = 0;
/* Buffer is initially large enough to hold most commands
but extends automatically when needed. */
int bufsize = 128;
buffer = grub_malloc (bufsize);
/* This is a variable, read the variable name. */
while (*state->script)
{
newstate = grub_parser_cmdline_state (state->state,
*state->script, &use);
/* Check if this character is not part of the variable name
anymore. */
if (! (check_varstate (newstate)))
{
if (state->state == GRUB_PARSER_STATE_VARNAME2
|| state->state == GRUB_PARSER_STATE_QVARNAME2)
nextchar (state);
state->state = newstate;
break;
}
if (use)
{
if (bufsize <= bufpos + 1)
{
bufsize <<= 1;
buffer = grub_realloc (buffer, bufsize);
}
buffer[bufpos++] = use;
}
nextchar (state);
state->state = newstate;
}
if (bufsize <= bufpos + 1)
{
bufsize <<= 1;
buffer = grub_realloc (buffer, bufsize);
}
buffer[bufpos++] = 0;
state->state = newstate;
yylval->arg = grub_script_arg_add (parsestate, yylval->arg,
GRUB_SCRIPT_ARG_TYPE_VAR, buffer);
grub_dprintf ("scripting", "vartoken=`%s'\n", buffer);
grub_free (buffer);
}
else
{
/* There is either text or a variable name. In the case you
arrive here there is a serious problem with the lexer. */
grub_error (GRUB_ERR_BAD_ARGUMENT, "Internal error\n");
return 0;
}
}
if (yylval->arg == 0)
{
int token = state->tokenonhold;
state->tokenonhold = 0;
return token;
}
if (yylval->arg->next == 0 && yylval->arg->type == GRUB_SCRIPT_ARG_TYPE_STR)
{
/* Detect some special tokens. */
if (! grub_strcmp (yylval->arg->str, "while"))
return GRUB_PARSER_TOKEN_WHILE;
else if (! grub_strcmp (yylval->arg->str, "if"))
return GRUB_PARSER_TOKEN_IF;
else if (! grub_strcmp (yylval->arg->str, "function"))
return GRUB_PARSER_TOKEN_FUNCTION;
else if (! grub_strcmp (yylval->arg->str, "menuentry"))
return GRUB_PARSER_TOKEN_MENUENTRY;
else if (! grub_strcmp (yylval->arg->str, "@"))
return GRUB_PARSER_TOKEN_MENUENTRY;
else if (! grub_strcmp (yylval->arg->str, "else"))
return GRUB_PARSER_TOKEN_ELSE;
else if (! grub_strcmp (yylval->arg->str, "then"))
return GRUB_PARSER_TOKEN_THEN;
else if (! grub_strcmp (yylval->arg->str, "fi"))
return GRUB_PARSER_TOKEN_FI;
}
return GRUB_PARSER_TOKEN_ARG;
}
void
grub_script_yyerror (struct grub_parser_param *lex __attribute__ ((unused)),
char const *err)
{
grub_printf ("%s\n", err);
}