/* echo.c - Command to display a line of text */
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2006,2007,2010 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/dl.h>
#include <grub/misc.h>
#include <grub/extcmd.h>
#include <grub/i18n.h>
#include <grub/term.h>
GRUB_MOD_LICENSE ("GPLv3+");
static const struct grub_arg_option options[] =
{
{0, 'n', 0, N_("Do not output the trailing newline."), 0, 0},
{0, 'e', 0, N_("Enable interpretation of backslash escapes."), 0, 0},
{0, 0, 0, 0, 0, 0}
};
static grub_err_t
grub_cmd_echo (grub_extcmd_context_t ctxt, int argc, char **args)
{
struct grub_arg_list *state = ctxt->state;
int newline = 1;
int i;
/* Check if `-n' was used. */
if (state[0].set)
newline = 0;
for (i = 0; i < argc; i++)
{
char *arg = *args;
/* Unescaping results in a string no longer than the original. */
char *unescaped = grub_malloc (grub_strlen (arg) + 1);
char *p = unescaped;
args++;
if (!unescaped)
return grub_errno;
while (*arg)
{
/* In case `-e' is used, parse backslashes. */
if (*arg == '\\' && state[1].set)
{
arg++;
if (*arg == '\0')
break;
switch (*arg)
{
case '\\':
*p++ = '\\';
break;
case 'a':
*p++ = '\a';
break;
case 'c':
newline = 0;
break;
case 'f':
*p++ = '\f';
break;
case 'n':
*p++ = '\n';
break;
case 'r':
*p++ = '\r';
break;
case 't':
*p++ = '\t';
break;
case 'v':
*p++ = '\v';
break;
}
arg++;
continue;
}
/* This was not an escaped character, or escaping is not
enabled. */
*p++ = *arg;
arg++;
}
*p = '\0';
grub_xputs (unescaped);
grub_free (unescaped);
/* If another argument follows, insert a space. */
if (i != argc - 1)
grub_printf (" " );
}
if (newline)
grub_printf ("\n");
grub_refresh ();
return 0;
}
static grub_extcmd_t cmd;
GRUB_MOD_INIT(echo)
{
cmd = grub_register_extcmd ("echo", grub_cmd_echo,
GRUB_COMMAND_ACCEPT_DASH
| GRUB_COMMAND_OPTIONS_AT_START,
N_("[-e|-n] STRING"), N_("Display a line of text."),
options);
}
GRUB_MOD_FINI(echo)
{
grub_unregister_extcmd (cmd);
}