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grub/grub-core/script/execute.c
James Le Cuirot 187338f1ac script/execute: Don't let trailing blank lines determine the return code 
The grub_script_execute_sourcecode() parses and executes code one line
at a time, updating the return code each time because only the last line
determines the final status. However, trailing new lines were also
executed, masking any failure on the previous line. Fix this by only
trying to execute the command when there is actually one present.

This has presumably never been noticed because this code is not used by
regular functions, only in special cases like eval and menu entries. The
latter generally don't return at all, having booted an OS. When failing
to boot, upstream GRUB triggers the fallback mechanism regardless of the
return code.

We noticed the problem while using Red Hat's patches, which change this
behaviour to take account of the return code. In that case, a failure
takes you back to the menu rather than triggering a fallback.

Signed-off-by: James Le Cuirot <jlecuirot@microsoft.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-03-05 12:11:09 +01:00

1213 lines
26 KiB
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/* execute.c -- Execute a GRUB script. */
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2005,2007,2008,2009,2010 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/misc.h>
#include <grub/mm.h>
#include <grub/env.h>
#include <grub/script_sh.h>
#include <grub/command.h>
#include <grub/menu.h>
#include <grub/lib/arg.h>
#include <grub/normal.h>
#include <grub/extcmd.h>
#include <grub/i18n.h>
#include <grub/verify.h>
/* Max digits for a char is 3 (0xFF is 255), similarly for an int it
is sizeof (int) * 3, and one extra for a possible -ve sign. */
#define ERRNO_DIGITS_MAX (sizeof (int) * 3 + 1)
/*
* A limit on recursion, to avoid colliding with the heap. UEFI defines a baseline
* stack size of 128 KiB. So, assuming at most 1-2 KiB per iteration this should
* keep us safe.
*/
#define MAX_RECURSION_DEPTH 64
static unsigned long is_continue;
static unsigned long active_loops;
static unsigned long active_breaks;
static unsigned long function_return;
static unsigned long recursion_depth;
#define GRUB_SCRIPT_SCOPE_MALLOCED 1
#define GRUB_SCRIPT_SCOPE_ARGS_MALLOCED 2
/* Scope for grub script functions. */
struct grub_script_scope
{
unsigned flags;
unsigned shifts;
struct grub_script_argv argv;
};
static struct grub_script_scope *scope = 0;
/* Wildcard translator for GRUB script. */
struct grub_script_wildcard_translator *grub_wildcard_translator;
static char*
wildcard_escape (const char *s)
{
int i;
int len;
char ch;
char *p;
len = grub_strlen (s);
p = grub_malloc (len * 2 + 1);
if (! p)
return NULL;
i = 0;
while ((ch = *s++))
{
if (ch == '*' || ch == '\\' || ch == '?')
p[i++] = '\\';
p[i++] = ch;
}
p[i] = '\0';
return p;
}
static char*
wildcard_unescape (const char *s)
{
int i;
int len;
char ch;
char *p;
len = grub_strlen (s);
p = grub_malloc (len + 1);
if (! p)
return NULL;
i = 0;
while ((ch = *s++))
{
if (ch == '\\')
p[i++] = *s++;
else
p[i++] = ch;
}
p[i] = '\0';
return p;
}
static void
replace_scope (struct grub_script_scope *new_scope)
{
if (scope)
{
scope->argv.argc += scope->shifts;
scope->argv.args -= scope->shifts;
if (scope->flags & GRUB_SCRIPT_SCOPE_ARGS_MALLOCED)
grub_script_argv_free (&scope->argv);
if (scope->flags & GRUB_SCRIPT_SCOPE_MALLOCED)
grub_free (scope);
}
scope = new_scope;
}
grub_err_t
grub_script_break (grub_command_t cmd, int argc, char *argv[])
{
const char *p = NULL;
unsigned long count;
if (argc == 0)
count = 1;
else if (argc > 1)
return grub_error (GRUB_ERR_BAD_ARGUMENT, N_("one argument expected"));
else
{
count = grub_strtoul (argv[0], &p, 10);
if (grub_errno)
return grub_errno;
if (*p != '\0')
return grub_error (GRUB_ERR_BAD_ARGUMENT, N_("unrecognized number"));
if (count == 0)
/* TRANSLATORS: 0 is a quantifier. "break" (similar to bash)
can be used e.g. to break 3 loops at once.
But asking it to break 0 loops makes no sense. */
return grub_error (GRUB_ERR_BAD_ARGUMENT, N_("can't break 0 loops"));
}
is_continue = grub_strcmp (cmd->name, "break") ? 1 : 0;
active_breaks = count;
if (active_breaks > active_loops)
active_breaks = active_loops;
return GRUB_ERR_NONE;
}
grub_err_t
grub_script_shift (grub_command_t cmd __attribute__((unused)),
int argc, char *argv[])
{
const char *p = NULL;
unsigned long n = 0;
if (! scope)
return GRUB_ERR_NONE;
if (argc == 0)
n = 1;
else if (argc > 1)
return GRUB_ERR_BAD_ARGUMENT;
else
{
n = grub_strtoul (argv[0], &p, 10);
if (*p != '\0')
return GRUB_ERR_BAD_ARGUMENT;
}
if (n > scope->argv.argc)
return GRUB_ERR_BAD_ARGUMENT;
scope->shifts += n;
scope->argv.argc -= n;
scope->argv.args += n;
return GRUB_ERR_NONE;
}
grub_err_t
grub_script_setparams (grub_command_t cmd __attribute__((unused)),
int argc, char **args)
{
struct grub_script_scope *new_scope;
struct grub_script_argv argv = { 0, 0, 0 };
if (! scope)
return GRUB_ERR_INVALID_COMMAND;
new_scope = grub_malloc (sizeof (*new_scope));
if (! new_scope)
return grub_errno;
if (grub_script_argv_make (&argv, argc, args))
{
grub_free (new_scope);
return grub_errno;
}
new_scope->shifts = 0;
new_scope->argv = argv;
new_scope->flags = GRUB_SCRIPT_SCOPE_MALLOCED |
GRUB_SCRIPT_SCOPE_ARGS_MALLOCED;
replace_scope (new_scope);
return GRUB_ERR_NONE;
}
grub_err_t
grub_script_return (grub_command_t cmd __attribute__((unused)),
int argc, char *argv[])
{
const char *p = NULL;
unsigned long n;
if (! scope || argc > 1)
return grub_error (GRUB_ERR_BAD_ARGUMENT,
/* TRANSLATORS: It's about not being
inside a function. "return" can be used only
in a function and this error occurs if it's used
anywhere else. */
N_("not in function body"));
if (argc == 0)
{
const char *t;
function_return = 1;
t = grub_env_get ("?");
if (!t)
return GRUB_ERR_NONE;
return grub_strtoul (t, NULL, 10);
}
n = grub_strtoul (argv[0], &p, 10);
if (grub_errno)
return grub_errno;
if (*p != '\0')
return grub_error (GRUB_ERR_BAD_ARGUMENT,
N_("unrecognized number"));
function_return = 1;
return n ? grub_error (n, N_("false")) : GRUB_ERR_NONE;
}
static int
grub_env_special (const char *name)
{
if (grub_isdigit (name[0]) ||
grub_strcmp (name, "#") == 0 ||
grub_strcmp (name, "*") == 0 ||
grub_strcmp (name, "@") == 0)
return 1;
return 0;
}
static char **
grub_script_env_get (const char *name, grub_script_arg_type_t type)
{
unsigned i;
struct grub_script_argv result = { 0, 0, 0 };
if (grub_script_argv_next (&result))
goto fail;
if (! grub_env_special (name))
{
const char *v = grub_env_get (name);
if (v && v[0])
{
if (type == GRUB_SCRIPT_ARG_TYPE_VAR)
{
if (grub_script_argv_split_append (&result, v))
goto fail;
}
else
if (grub_script_argv_append (&result, v, grub_strlen (v)))
goto fail;
}
}
else if (! scope)
{
if (grub_script_argv_append (&result, 0, 0))
goto fail;
}
else if (grub_strcmp (name, "#") == 0)
{
char buffer[ERRNO_DIGITS_MAX + 1];
grub_snprintf (buffer, sizeof (buffer), "%u", scope->argv.argc);
if (grub_script_argv_append (&result, buffer, grub_strlen (buffer)))
goto fail;
}
else if (grub_strcmp (name, "*") == 0)
{
for (i = 0; i < scope->argv.argc; i++)
if (type == GRUB_SCRIPT_ARG_TYPE_VAR)
{
if (i != 0 && grub_script_argv_next (&result))
goto fail;
if (grub_script_argv_split_append (&result, scope->argv.args[i]))
goto fail;
}
else
{
if (i != 0 && grub_script_argv_append (&result, " ", 1))
goto fail;
if (grub_script_argv_append (&result, scope->argv.args[i],
grub_strlen (scope->argv.args[i])))
goto fail;
}
}
else if (grub_strcmp (name, "@") == 0)
{
for (i = 0; i < scope->argv.argc; i++)
{
if (i != 0 && grub_script_argv_next (&result))
goto fail;
if (type == GRUB_SCRIPT_ARG_TYPE_VAR)
{
if (grub_script_argv_split_append (&result, scope->argv.args[i]))
goto fail;
}
else
if (grub_script_argv_append (&result, scope->argv.args[i],
grub_strlen (scope->argv.args[i])))
goto fail;
}
}
else
{
unsigned long num = grub_strtoul (name, 0, 10);
if (num == 0)
; /* XXX no file name, for now. */
else if (num <= scope->argv.argc)
{
if (type == GRUB_SCRIPT_ARG_TYPE_VAR)
{
if (grub_script_argv_split_append (&result,
scope->argv.args[num - 1]))
goto fail;
}
else
if (grub_script_argv_append (&result, scope->argv.args[num - 1],
grub_strlen (scope->argv.args[num - 1])
))
goto fail;
}
}
return result.args;
fail:
grub_script_argv_free (&result);
return 0;
}
static grub_err_t
grub_script_env_set (const char *name, const char *val)
{
if (grub_env_special (name))
return grub_error (GRUB_ERR_BAD_ARGUMENT,
N_("invalid variable name `%s'"), name);
return grub_env_set (name, val);
}
struct gettext_context
{
char **allowed_strings;
grub_size_t nallowed_strings;
grub_size_t additional_len;
};
static int
parse_string (const char *str,
int (*hook) (const char *var, grub_size_t varlen,
char **ptr, struct gettext_context *ctx),
struct gettext_context *ctx,
char *put)
{
const char *ptr;
int escaped = 0;
const char *optr;
for (ptr = str; ptr && *ptr; )
switch (*ptr)
{
case '\\':
escaped = !escaped;
if (!escaped && put)
*(put++) = '\\';
ptr++;
break;
case '$':
if (escaped)
{
escaped = 0;
if (put)
*(put++) = *ptr;
ptr++;
break;
}
ptr++;
switch (*ptr)
{
case '{':
{
optr = ptr + 1;
ptr = grub_strchr (optr, '}');
if (!ptr)
break;
if (hook (optr, ptr - optr, &put, ctx))
return 1;
ptr++;
break;
}
case '0' ... '9':
optr = ptr;
while (*ptr >= '0' && *ptr <= '9')
ptr++;
if (hook (optr, ptr - optr, &put, ctx))
return 1;
break;
case 'a' ... 'z':
case 'A' ... 'Z':
case '_':
optr = ptr;
while ((*ptr >= '0' && *ptr <= '9')
|| (*ptr >= 'a' && *ptr <= 'z')
|| (*ptr >= 'A' && *ptr <= 'Z')
|| *ptr == '_')
ptr++;
if (hook (optr, ptr - optr, &put, ctx))
return 1;
break;
case '?':
case '#':
if (hook (ptr, 1, &put, ctx))
return 1;
ptr++;
break;
default:
if (put)
*(put++) = '$';
}
break;
default:
if (escaped && put)
*(put++) = '\\';
escaped = 0;
if (put)
*(put++) = *ptr;
ptr++;
break;
}
if (put)
*(put++) = 0;
return 0;
}
static int
gettext_putvar (const char *str, grub_size_t len,
char **ptr, struct gettext_context *ctx)
{
const char *var;
grub_size_t i;
for (i = 0; i < ctx->nallowed_strings; i++)
if (grub_strncmp (ctx->allowed_strings[i], str, len) == 0
&& ctx->allowed_strings[i][len] == 0)
{
break;
}
if (i == ctx->nallowed_strings)
return 0;
/* Enough for any number. */
if (len == 1 && str[0] == '#' && scope != NULL)
{
grub_snprintf (*ptr, 30, "%u", scope->argv.argc);
*ptr += grub_strlen (*ptr);
return 0;
}
var = grub_env_get (ctx->allowed_strings[i]);
if (var)
*ptr = grub_stpcpy (*ptr, var);
return 0;
}
static int
gettext_save_allow (const char *str, grub_size_t len,
char **ptr __attribute__ ((unused)),
struct gettext_context *ctx)
{
ctx->allowed_strings[ctx->nallowed_strings++] = grub_strndup (str, len);
if (!ctx->allowed_strings[ctx->nallowed_strings - 1])
return 1;
return 0;
}
static int
gettext_getlen (const char *str, grub_size_t len,
char **ptr __attribute__ ((unused)),
struct gettext_context *ctx)
{
const char *var;
grub_size_t i;
for (i = 0; i < ctx->nallowed_strings; i++)
if (grub_strncmp (ctx->allowed_strings[i], str, len) == 0
&& ctx->allowed_strings[i][len] == 0)
break;
if (i == ctx->nallowed_strings)
return 0;
/* Enough for any number. */
if (len == 1 && str[0] == '#')
{
ctx->additional_len += 30;
return 0;
}
var = grub_env_get (ctx->allowed_strings[i]);
if (var)
ctx->additional_len += grub_strlen (var);
return 0;
}
static int
gettext_append (struct grub_script_argv *result, const char *orig_str)
{
const char *template;
char *res = 0;
struct gettext_context ctx = {
.allowed_strings = 0,
.nallowed_strings = 0,
.additional_len = 1
};
int rval = 1;
const char *iptr;
grub_size_t dollar_cnt = 0;
for (iptr = orig_str; *iptr; iptr++)
if (*iptr == '$')
dollar_cnt++;
ctx.allowed_strings = grub_calloc (dollar_cnt, sizeof (ctx.allowed_strings[0]));
if (parse_string (orig_str, gettext_save_allow, &ctx, 0))
goto fail;
template = _(orig_str);
if (parse_string (template, gettext_getlen, &ctx, 0))
goto fail;
res = grub_malloc (grub_strlen (template) + ctx.additional_len);
if (!res)
goto fail;
if (parse_string (template, gettext_putvar, &ctx, res))
goto fail;
char *escaped = 0;
escaped = wildcard_escape (res);
if (grub_script_argv_append (result, escaped, grub_strlen (escaped)))
{
grub_free (escaped);
goto fail;
}
grub_free (escaped);
rval = 0;
fail:
grub_free (res);
{
grub_size_t i;
for (i = 0; i < ctx.nallowed_strings; i++)
grub_free (ctx.allowed_strings[i]);
}
grub_free (ctx.allowed_strings);
return rval;
}
static int
append (struct grub_script_argv *result,
const char *s, int escape_type)
{
int r;
char *p = 0;
if (escape_type == 0)
return grub_script_argv_append (result, s, grub_strlen (s));
if (escape_type > 0)
p = wildcard_escape (s);
else if (escape_type < 0)
p = wildcard_unescape (s);
if (! p)
return 1;
r = grub_script_argv_append (result, p, grub_strlen (p));
grub_free (p);
return r;
}
/* Convert arguments in ARGLIST into ARGV form. */
static int
grub_script_arglist_to_argv (struct grub_script_arglist *arglist,
struct grub_script_argv *argv)
{
int i;
char **values = 0;
struct grub_script_arg *arg = 0;
struct grub_script_argv result = { 0, 0, 0 };
if (arglist == NULL)
return 1;
for (; arglist && arglist->arg; arglist = arglist->next)
{
if (grub_script_argv_next (&result))
goto fail;
arg = arglist->arg;
while (arg)
{
switch (arg->type)
{
case GRUB_SCRIPT_ARG_TYPE_VAR:
case GRUB_SCRIPT_ARG_TYPE_DQVAR:
{
int need_cleanup = 0;
values = grub_script_env_get (arg->str, arg->type);
for (i = 0; values && values[i]; i++)
{
if (!need_cleanup)
{
if (i != 0 && grub_script_argv_next (&result))
{
need_cleanup = 1;
goto cleanup;
}
if (arg->type == GRUB_SCRIPT_ARG_TYPE_VAR)
{
int len;
char ch;
char *p;
char *op;
const char *s = values[i];
len = grub_strlen (values[i]);
/* \? -> \\\? */
/* \* -> \\\* */
/* \ -> \\ */
p = grub_malloc (len * 2 + 1);
if (! p)
{
need_cleanup = 1;
goto cleanup;
}
op = p;
while ((ch = *s++))
{
if (ch == '\\')
{
*op++ = '\\';
if (*s == '?' || *s == '*')
*op++ = '\\';
}
*op++ = ch;
}
*op = '\0';
need_cleanup = grub_script_argv_append (&result, p, op - p);
grub_free (p);
/* Fall through to cleanup */
}
else
{
need_cleanup = append (&result, values[i], 1);
/* Fall through to cleanup */
}
}
cleanup:
grub_free (values[i]);
}
grub_free (values);
if (need_cleanup)
goto fail;
break;
}
case GRUB_SCRIPT_ARG_TYPE_BLOCK:
{
char *p;
if (grub_script_argv_append (&result, "{", 1))
goto fail;
p = wildcard_escape (arg->str);
if (!p)
goto fail;
if (grub_script_argv_append (&result, p,
grub_strlen (p)))
{
grub_free (p);
goto fail;
}
grub_free (p);
if (grub_script_argv_append (&result, "}", 1))
goto fail;
}
result.script = arg->script;
break;
case GRUB_SCRIPT_ARG_TYPE_TEXT:
if (arg->str[0] &&
grub_script_argv_append (&result, arg->str,
grub_strlen (arg->str)))
goto fail;
break;
case GRUB_SCRIPT_ARG_TYPE_GETTEXT:
{
if (gettext_append (&result, arg->str))
goto fail;
}
break;
case GRUB_SCRIPT_ARG_TYPE_DQSTR:
case GRUB_SCRIPT_ARG_TYPE_SQSTR:
if (append (&result, arg->str, 1))
goto fail;
break;
}
arg = arg->next;
}
}
if (result.args == NULL || result.argc == 0)
goto fail;
if (! result.args[result.argc - 1])
result.argc--;
/* Perform wildcard expansion. */
int j;
int failed = 0;
struct grub_script_argv unexpanded = result;
result.argc = 0;
result.args = 0;
for (i = 0; unexpanded.args[i]; i++)
{
char **expansions = 0;
if (grub_wildcard_translator
&& grub_wildcard_translator->expand (unexpanded.args[i],
&expansions))
{
grub_script_argv_free (&unexpanded);
goto fail;
}
if (! expansions)
{
grub_script_argv_next (&result);
append (&result, unexpanded.args[i], -1);
}
else
{
for (j = 0; expansions[j]; j++)
{
failed = (failed || grub_script_argv_next (&result) ||
append (&result, expansions[j], 0));
grub_free (expansions[j]);
}
grub_free (expansions);
if (failed)
{
grub_script_argv_free (&unexpanded);
goto fail;
}
}
}
grub_script_argv_free (&unexpanded);
*argv = result;
return 0;
fail:
grub_script_argv_free (&result);
return 1;
}
static grub_err_t
grub_script_execute_cmd (struct grub_script_cmd *cmd)
{
int ret;
char errnobuf[ERRNO_DIGITS_MAX + 1];
if (cmd == 0)
return 0;
recursion_depth++;
if (recursion_depth >= MAX_RECURSION_DEPTH)
return grub_error (GRUB_ERR_RECURSION_DEPTH, N_("maximum recursion depth exceeded"));
ret = cmd->exec (cmd);
recursion_depth--;
grub_snprintf (errnobuf, sizeof (errnobuf), "%d", ret);
grub_env_set ("?", errnobuf);
return ret;
}
/* Execute a function call. */
grub_err_t
grub_script_function_call (grub_script_function_t func, int argc, char **args)
{
grub_err_t ret = 0;
unsigned long loops = active_loops;
struct grub_script_scope *old_scope;
struct grub_script_scope new_scope;
active_loops = 0;
new_scope.flags = 0;
new_scope.shifts = 0;
new_scope.argv.argc = argc;
new_scope.argv.args = args;
old_scope = scope;
scope = &new_scope;
func->executing++;
ret = grub_script_execute (func->func);
func->executing--;
function_return = 0;
active_loops = loops;
replace_scope (old_scope); /* free any scopes by setparams */
return ret;
}
/* Helper for grub_script_execute_sourcecode. */
static grub_err_t
grub_script_execute_sourcecode_getline (char **line,
int cont __attribute__ ((unused)),
void *data)
{
const char **source = data;
const char *p;
if (! *source)
{
*line = 0;
return 0;
}
p = grub_strchr (*source, '\n');
if (p)
*line = grub_strndup (*source, p - *source);
else
*line = grub_strdup (*source);
*source = p ? p + 1 : 0;
return 0;
}
/* Execute a source script. */
grub_err_t
grub_script_execute_sourcecode (const char *source)
{
grub_err_t ret = 0;
struct grub_script *parsed_script;
while (source)
{
char *line;
grub_script_execute_sourcecode_getline (&line, 0, &source);
parsed_script = grub_script_parse
(line, grub_script_execute_sourcecode_getline, &source);
if (! parsed_script)
{
ret = grub_errno;
grub_free (line);
break;
}
/* Don't let trailing blank lines determine the return code. */
if (parsed_script->cmd)
ret = grub_script_execute (parsed_script);
grub_script_free (parsed_script);
grub_free (line);
}
return ret;
}
/* Execute a source script in new scope. */
grub_err_t
grub_script_execute_new_scope (const char *source, int argc, char **args)
{
grub_err_t ret = 0;
struct grub_script_scope new_scope;
struct grub_script_scope *old_scope;
new_scope.argv.argc = argc;
new_scope.argv.args = args;
new_scope.flags = 0;
old_scope = scope;
scope = &new_scope;
ret = grub_script_execute_sourcecode (source);
scope = old_scope;
return ret;
}
/* Execute a single command line. */
grub_err_t
grub_script_execute_cmdline (struct grub_script_cmd *cmd)
{
struct grub_script_cmdline *cmdline = (struct grub_script_cmdline *) cmd;
grub_command_t grubcmd;
grub_err_t ret = 0;
grub_script_function_t func = 0;
char errnobuf[18];
char *cmdname, *cmdstring;
int argc, offset = 0, cmdlen = 0;
unsigned int i;
char **args;
int invert;
struct grub_script_argv argv = { 0, 0, 0 };
/* Lookup the command. */
if (grub_script_arglist_to_argv (cmdline->arglist, &argv) || ! argv.args || ! argv.args[0])
return grub_errno;
for (i = 0; i < argv.argc; i++)
{
cmdlen += grub_strlen (argv.args[i]) + 1;
}
cmdstring = grub_malloc (cmdlen);
if (!cmdstring)
{
return grub_error (GRUB_ERR_OUT_OF_MEMORY,
N_("cannot allocate command buffer"));
}
for (i = 0; i < argv.argc; i++)
{
offset += grub_snprintf (cmdstring + offset, cmdlen - offset, "%s ",
argv.args[i]);
}
cmdstring[cmdlen - 1] = '\0';
grub_verify_string (cmdstring, GRUB_VERIFY_COMMAND);
grub_free (cmdstring);
invert = 0;
argc = argv.argc - 1;
args = argv.args + 1;
cmdname = argv.args[0];
if (grub_strcmp (cmdname, "!") == 0)
{
if (argv.argc < 2 || ! argv.args[1])
{
grub_script_argv_free (&argv);
return grub_error (GRUB_ERR_BAD_ARGUMENT,
N_("no command is specified"));
}
invert = 1;
argc = argv.argc - 2;
args = argv.args + 2;
cmdname = argv.args[1];
}
grubcmd = grub_command_find (cmdname);
if (! grubcmd)
{
grub_errno = GRUB_ERR_NONE;
/* It's not a GRUB command, try all functions. */
func = grub_script_function_find (cmdname);
if (! func)
{
/* As a last resort, try if it is an assignment. */
char *assign = grub_strdup (cmdname);
char *eq = grub_strchr (assign, '=');
if (eq)
{
/* This was set because the command was not found. */
grub_errno = GRUB_ERR_NONE;
/* Create two strings and set the variable. */
*eq = '\0';
eq++;
grub_script_env_set (assign, eq);
}
grub_free (assign);
grub_snprintf (errnobuf, sizeof (errnobuf), "%d", grub_errno);
grub_script_env_set ("?", errnobuf);
grub_script_argv_free (&argv);
grub_print_error ();
return 0;
}
}
/* Execute the GRUB command or function. */
if (grubcmd)
{
if (grub_extractor_level && !(grubcmd->flags
& GRUB_COMMAND_FLAG_EXTRACTOR))
ret = grub_error (GRUB_ERR_EXTRACTOR,
"%s isn't allowed to execute in an extractor",
cmdname);
else if ((grubcmd->flags & GRUB_COMMAND_FLAG_BLOCKS) &&
(grubcmd->flags & GRUB_COMMAND_FLAG_EXTCMD))
ret = grub_extcmd_dispatcher (grubcmd, argc, args, argv.script);
else
ret = (grubcmd->func) (grubcmd, argc, args);
}
else
ret = grub_script_function_call (func, argc, args);
if (invert)
{
if (ret == GRUB_ERR_TEST_FAILURE)
grub_errno = ret = GRUB_ERR_NONE;
else if (ret == GRUB_ERR_NONE)
ret = grub_error (GRUB_ERR_TEST_FAILURE, N_("false"));
else
{
grub_print_error ();
ret = GRUB_ERR_NONE;
}
}
/* Free arguments. */
grub_script_argv_free (&argv);
if (grub_errno == GRUB_ERR_TEST_FAILURE)
grub_errno = GRUB_ERR_NONE;
grub_print_error ();
grub_snprintf (errnobuf, sizeof (errnobuf), "%d", ret);
grub_env_set ("?", errnobuf);
return ret;
}
/* Execute a block of one or more commands. */
grub_err_t
grub_script_execute_cmdlist (struct grub_script_cmd *list)
{
int ret = 0;
struct grub_script_cmd *cmd;
/* Loop over every command and execute it. */
for (cmd = list->next; cmd; cmd = cmd->next)
{
if (active_breaks)
break;
ret = grub_script_execute_cmd (cmd);
if (function_return)
break;
}
return ret;
}
/* Execute an if statement. */
grub_err_t
grub_script_execute_cmdif (struct grub_script_cmd *cmd)
{
int ret;
const char *result;
struct grub_script_cmdif *cmdif = (struct grub_script_cmdif *) cmd;
/* Check if the commands results in a true or a false. The value is
read from the env variable `?'. */
ret = grub_script_execute_cmd (cmdif->exec_to_evaluate);
if (function_return)
return ret;
result = grub_env_get ("?");
grub_errno = GRUB_ERR_NONE;
/* Execute the `if' or the `else' part depending on the value of
`?'. */
if (result && ! grub_strcmp (result, "0"))
return grub_script_execute_cmd (cmdif->exec_on_true);
else
return grub_script_execute_cmd (cmdif->exec_on_false);
}
/* Execute a for statement. */
grub_err_t
grub_script_execute_cmdfor (struct grub_script_cmd *cmd)
{
unsigned i;
grub_err_t result;
struct grub_script_argv argv = { 0, 0, 0 };
struct grub_script_cmdfor *cmdfor = (struct grub_script_cmdfor *) cmd;
if (grub_script_arglist_to_argv (cmdfor->words, &argv))
return grub_errno;
active_loops++;
result = 0;
for (i = 0; i < argv.argc; i++)
{
if (is_continue && active_breaks == 1)
active_breaks = 0;
if (! active_breaks)
{
grub_script_env_set (cmdfor->name->str, argv.args[i]);
result = grub_script_execute_cmd (cmdfor->list);
if (function_return)
break;
}
}
if (active_breaks)
active_breaks--;
active_loops--;
grub_script_argv_free (&argv);
return result;
}
/* Execute a "while" or "until" command. */
grub_err_t
grub_script_execute_cmdwhile (struct grub_script_cmd *cmd)
{
int result;
struct grub_script_cmdwhile *cmdwhile = (struct grub_script_cmdwhile *) cmd;
active_loops++;
do {
result = grub_script_execute_cmd (cmdwhile->cond);
if (function_return)
break;
if (cmdwhile->until ? !result : result)
break;
result = grub_script_execute_cmd (cmdwhile->list);
if (function_return)
break;
if (active_breaks == 1 && is_continue)
active_breaks = 0;
if (active_breaks)
break;
} while (1); /* XXX Put a check for ^C here */
if (active_breaks)
active_breaks--;
active_loops--;
return result;
}
/* Execute any GRUB pre-parsed command or script. */
grub_err_t
grub_script_execute (struct grub_script *script)
{
if (script == 0)
return 0;
return grub_script_execute_cmd (script->cmd);
}
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