commands/echo.c

   1 /*
   2  * echo.c - echo arguments to stdout or into a file
   3  *
   4  * Copyright (c) 2007 Sascha Hauer <s.hauer@pengutronix.de>, Pengutronix
   5  *
   6  * See file CREDITS for list of people who contributed to this
   7  * project.
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2
  11  * as published by the Free Software Foundation.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  21  */
  22
  23 #include <common.h>
  24 #include <command.h>
  25 #include <fs.h>
  26 #include <fcntl.h>
  27 #include <errno.h>
  28 #include <libbb.h>
  29
  30 static int do_echo(struct command *cmdtp, int argc, char *argv[])
  31 {
  32         int i, optind = 1;
  33         int fd = stdout, opt, newline = 1;
  34         char *file = NULL;
  35         int oflags = O_WRONLY | O_CREAT;
  36 #ifdef CONFIG_CMD_ECHO_E
  37         char str[CONFIG_CBSIZE];
  38         int process_escape = 0;
  39 #endif
  40         /* We can't use getopt() here because we want to
  41          * echo all things we don't understand.
  42          */
  43         while (optind < argc && *argv[optind] == '-') {
  44                 if (!*(argv[optind] + 1) || *(argv[optind] + 2))
  45                         break;
  46
  47                 opt = *(argv[optind] + 1);
  48                 switch (opt) {
  49                 case 'n':
  50                         newline = 0;
  51                         break;
  52                 case 'a':
  53                         oflags |= O_APPEND;
  54                         if (optind + 1 < argc)
  55                                 file = argv[optind + 1];
  56                         else
  57                                 goto no_optarg_out;
  58                         optind++;
  59                         break;
  60                 case 'o':
  61                         oflags |= O_TRUNC;
  62                         file = argv[optind + 1];
  63                         if (optind + 1 < argc)
  64                                 file = argv[optind + 1];
  65                         else
  66                                 goto no_optarg_out;
  67                         optind++;
  68                         break;
  69 #ifdef CONFIG_CMD_ECHO_E
  70                 case 'e':
  71                         process_escape = 1;
  72                         break;
  73 #endif
  74                 default:
  75                         goto exit_parse;
  76                 }
  77                 optind++;
  78         }
  79
  80 exit_parse:
  81         if (file) {
  82                 fd = open(file, oflags);
  83                 if (fd < 0) {
  84                         perror("open");
  85                         return 1;
  86                 }
  87         }
  88
  89         for (i = optind; i < argc; i++) {
  90                 if (i > optind)
  91                         fputc(fd, ' ');
  92 #ifdef CONFIG_CMD_ECHO_E
  93                 if (process_escape) {
  94                         process_escape_sequence(argv[i], str, CONFIG_CBSIZE);
  95                         fputs(fd, str);
  96                 } else
  97 #endif
  98                         fputs(fd, argv[i]);
  99         }
 100
 101         if (newline)
 102                 fputc(fd, '\n');
 103
 104         if (file)
 105                 close(fd);
 106
 107         return 0;
 108
 109 no_optarg_out:
 110         printf("option requires an argument -- %c\n", opt);
 111         return 1;
 112 }
 113
 114 BAREBOX_CMD_START(echo)
 115         .cmd            = do_echo,
 116         .usage          = "echo args to console",
 117 BAREBOX_CMD_END
 118