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
  29 static int do_echo (cmd_tbl_t *cmdtp, int argc, char *argv[])
  30 {
  31         int i, optind = 1;
  32         int fd = stdout, opt, newline = 1;
  33         char *file = NULL;
  34         int oflags = O_WRONLY | O_CREAT;
  35
  36         /* We can't use getopt() here because we want to
  37          * echo all things we don't understand.
  38          */
  39         while (optind < argc && *argv[optind] == '-') {
  40                 if (!*(argv[optind] + 1) || *(argv[optind] + 2))
  41                         break;
  42
  43                 opt = *(argv[optind] + 1);
  44                 switch (opt) {
  45                 case 'n':
  46                         newline = 0;
  47                         break;
  48                 case 'a':
  49                         oflags |= O_APPEND;
  50                         if (optind + 1 < argc)
  51                                 file = argv[optind + 1];
  52                         else
  53                                 goto no_optarg_out;
  54                         optind++;
  55                         break;
  56                 case 'o':
  57                         oflags |= O_TRUNC;
  58                         file = argv[optind + 1];
  59                         if (optind + 1 < argc)
  60                                 file = argv[optind + 1];
  61                         else
  62                                 goto no_optarg_out;
  63                         optind++;
  64                         break;
  65                 default:
  66                         goto exit_parse;
  67                 }
  68                 optind++;
  69         }
  70
  71 exit_parse:
  72         if (file) {
  73                 fd = open(file, oflags);
  74                 if (fd < 0) {
  75                         perror("open");
  76                         return 1;
  77                 }
  78         }
  79
  80         for (i = optind; i < argc; i++) {
  81                 if (i > optind)
  82                         fputc(fd, ' ');
  83                 fputs(fd, argv[i]);
  84         }
  85
  86         if (newline)
  87                 fputc(fd, '\n');
  88
  89         if (file)
  90                 close(fd);
  91
  92         return 0;
  93
  94 no_optarg_out:
  95         printf("option requires an argument -- %c\n", opt);
  96         return 1;
  97 }
  98
  99 U_BOOT_CMD_START(echo)
 100         .cmd            = do_echo,
 101         .usage          = "echo args to console",
 102 U_BOOT_CMD_END
 103