| /* echo.c - Command to display a line of text */ |
| /* |
| * GRUB -- GRand Unified Bootloader |
| * Copyright (C) 2006,2007 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> |
| |
| static const struct grub_arg_option options[] = |
| { |
| {0, 'n', 0, "do not output the trailing newline", 0, 0}, |
| {0, 'e', 0, "enable interpretation of backslash escapes", 0, 0}, |
| {0, 0, 0, 0, 0, 0} |
| }; |
| |
| static grub_err_t |
| grub_cmd_echo (grub_extcmd_t cmd, int argc, char **args) |
| { |
| struct grub_arg_list *state = cmd->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; |
| args++; |
| |
| while (*arg) |
| { |
| /* In case `-e' is used, parse backslashes. */ |
| if (*arg == '\\' && state[1].set) |
| { |
| arg++; |
| if (*arg == '\0') |
| break; |
| |
| switch (*arg) |
| { |
| case '\\': |
| grub_printf ("\\"); |
| break; |
| |
| case 'a': |
| grub_printf ("\a"); |
| break; |
| |
| case 'c': |
| newline = 0; |
| break; |
| |
| case 'f': |
| grub_printf ("\f"); |
| break; |
| |
| case 'n': |
| grub_printf ("\n"); |
| break; |
| |
| case 'r': |
| grub_printf ("\r"); |
| break; |
| |
| case 't': |
| grub_printf ("\t"); |
| break; |
| |
| case 'v': |
| grub_printf ("\v"); |
| break; |
| } |
| arg++; |
| continue; |
| } |
| |
| /* This was not an escaped character, or escaping is not |
| enabled. */ |
| grub_printf ("%c", *arg); |
| arg++; |
| } |
| |
| /* If another argument follows, insert a space. */ |
| if (i != argc - 1) |
| grub_printf (" " ); |
| } |
| |
| if (newline) |
| grub_printf ("\n"); |
| |
| return 0; |
| } |
| |
| static grub_extcmd_t cmd; |
| |
| GRUB_MOD_INIT(echo) |
| { |
| cmd = grub_register_extcmd ("echo", grub_cmd_echo, GRUB_COMMAND_FLAG_BOTH, |
| "echo [-e|-n] STRING", "Display a line of text.", |
| options); |
| } |
| |
| GRUB_MOD_FINI(echo) |
| { |
| grub_unregister_extcmd (cmd); |
| } |