src/tee.c

   1 /* tee - read from standard input and write to standard output and files.
   2    Copyright (C) 85,1990-2004 Free Software Foundation, Inc.
   3
   4    This program is free software; you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation; either version 2, or (at your option)
   7    any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program; if not, write to the Free Software Foundation,
  16    Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  17
  18 /* Mike Parker, Richard M. Stallman, and David MacKenzie */
  19
  20 #include <config.h>
  21 #include <stdio.h>
  22 #include <sys/types.h>
  23 #include <signal.h>
  24 #include <getopt.h>
  25
  26 #include "system.h"
  27 #include "error.h"
  28
  29 /* The official name of this program (e.g., no `g' prefix).  */
  30 #define PROGRAM_NAME "tee"
  31
  32 #define AUTHORS "Mike Parker", "Richard M. Stallman", "David MacKenzie"
  33
  34 static bool tee (int nfiles, const char **files);
  35
  36 /* If true, append to output files rather than truncating them. */
  37 static bool append;
  38
  39 /* If true, ignore interrupts. */
  40 static bool ignore_interrupts;
  41
  42 /* The name that this program was run with. */
  43 char *program_name;
  44
  45 static struct option const long_options[] =
  46 {
  47   {"append", no_argument, NULL, 'a'},
  48   {"ignore-interrupts", no_argument, NULL, 'i'},
  49   {GETOPT_HELP_OPTION_DECL},
  50   {GETOPT_VERSION_OPTION_DECL},
  51   {NULL, 0, NULL, 0}
  52 };
  53
  54 void
  55 usage (int status)
  56 {
  57   if (status != EXIT_SUCCESS)
  58     fprintf (stderr, _("Try `%s --help' for more information.\n"),
  59              program_name);
  60   else
  61     {
  62       printf (_("Usage: %s [OPTION]... [FILE]...\n"), program_name);
  63       fputs (_("\
  64 Copy standard input to each FILE, and also to standard output.\n\
  65 \n\
  66   -a, --append              append to the given FILEs, do not overwrite\n\
  67   -i, --ignore-interrupts   ignore interrupt signals\n\
  68 "), stdout);
  69       fputs (HELP_OPTION_DESCRIPTION, stdout);
  70       fputs (VERSION_OPTION_DESCRIPTION, stdout);
  71       fputs (_("\
  72 \n\
  73 If a FILE is -, copy again to standard output.\n\
  74 "), stdout);
  75       printf (_("\nReport bugs to <%s>.\n"), PACKAGE_BUGREPORT);
  76     }
  77   exit (status);
  78 }
  79
  80 int
  81 main (int argc, char **argv)
  82 {
  83   bool ok;
  84   int optc;
  85
  86   initialize_main (&argc, &argv);
  87   program_name = argv[0];
  88   setlocale (LC_ALL, "");
  89   bindtextdomain (PACKAGE, LOCALEDIR);
  90   textdomain (PACKAGE);
  91
  92   atexit (close_stdout);
  93
  94   append = false;
  95   ignore_interrupts = false;
  96
  97   while ((optc = getopt_long (argc, argv, "ai", long_options, NULL)) != -1)
  98     {
  99       switch (optc)
 100         {
 101         case 'a':
 102           append = true;
 103           break;
 104
 105         case 'i':
 106           ignore_interrupts = true;
 107           break;
 108
 109         case_GETOPT_HELP_CHAR;
 110
 111         case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
 112
 113         default:
 114           usage (EXIT_FAILURE);
 115         }
 116     }
 117
 118   if (ignore_interrupts)
 119     signal (SIGINT, SIG_IGN);
 120
 121   /* Do *not* warn if tee is given no file arguments.
 122      POSIX requires that it work when given no arguments.  */
 123
 124   ok = tee (argc - optind, (const char **) &argv[optind]);
 125   if (close (STDIN_FILENO) != 0)
 126     error (EXIT_FAILURE, errno, _("standard input"));
 127
 128   exit (ok ? EXIT_SUCCESS : EXIT_FAILURE);
 129 }
 130
 131 /* Copy the standard input into each of the NFILES files in FILES
 132    and into the standard output.
 133    Return true if successful.  */
 134
 135 static bool
 136 tee (int nfiles, const char **files)
 137 {
 138   FILE **descriptors;
 139   char buffer[BUFSIZ];
 140   ssize_t bytes_read;
 141   int i;
 142   bool ok = true;
 143   const char *mode_string = (append ? "a" : "w");
 144
 145   descriptors = xnmalloc (nfiles + 1, sizeof *descriptors);
 146
 147   /* Move all the names `up' one in the argv array to make room for
 148      the entry for standard output.  This writes into argv[argc].  */
 149   for (i = nfiles; i >= 1; i--)
 150     files[i] = files[i - 1];
 151
 152   SET_BINARY2 (0, 1);
 153
 154   /* In the array of NFILES + 1 descriptors, make
 155      the first one correspond to standard output.   */
 156   descriptors[0] = stdout;
 157   files[0] = _("standard output");
 158   SETVBUF (stdout, NULL, _IONBF, 0);
 159
 160   for (i = 1; i <= nfiles; i++)
 161     {
 162       descriptors[i] = (STREQ (files[i], "-")
 163                         ? stdout
 164                         : fopen (files[i], mode_string));
 165       if (descriptors[i] == NULL)
 166         {
 167           error (0, errno, "%s", files[i]);
 168           ok = false;
 169         }
 170       else
 171         {
 172           SETVBUF (descriptors[i], NULL, _IONBF, 0);
 173           SET_BINARY (fileno (descriptors[i]));
 174         }
 175     }
 176
 177   while (1)
 178     {
 179       bytes_read = read (0, buffer, sizeof buffer);
 180 #ifdef EINTR
 181       if (bytes_read < 0 && errno == EINTR)
 182         continue;
 183 #endif
 184       if (bytes_read <= 0)
 185         break;
 186
 187       /* Write to all NFILES + 1 descriptors.
 188          Standard output is the first one.  */
 189       for (i = 0; i <= nfiles; i++)
 190         if (descriptors[i]
 191             && fwrite (buffer, 1, bytes_read, descriptors[i]) != bytes_read)
 192           {
 193             error (0, errno, "%s", files[i]);
 194             descriptors[i] = NULL;
 195             ok = false;
 196           }
 197     }
 198
 199   if (bytes_read == -1)
 200     {
 201       error (0, errno, _("read error"));
 202       ok = false;
 203     }
 204
 205   /* Close the files, but not standard output.  */
 206   for (i = 1; i <= nfiles; i++)
 207     if (descriptors[i] && fclose (descriptors[i]) != 0)
 208       {
 209         error (0, errno, "%s", files[i]);
 210         ok = false;
 211       }
 212
 213   free (descriptors);
 214
 215   return ok;
 216 }