src/tee.c

   1 /* tee - read from standard input and write to standard output and files.
   2    Copyright (C) 85,1990-2002 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 "closeout.h"
  28 #include "error.h"
  29
  30 /* The official name of this program (e.g., no `g' prefix).  */
  31 #define PROGRAM_NAME "tee"
  32
  33 #define AUTHORS N_ ("Mike Parker, Richard M. Stallman, and David MacKenzie")
  34
  35 static int tee (int nfiles, const char **files);
  36
  37 /* If nonzero, append to output files rather than truncating them. */
  38 static int append;
  39
  40 /* If nonzero, ignore interrupts. */
  41 static int ignore_interrupts;
  42
  43 /* The name that this program was run with. */
  44 char *program_name;
  45
  46 static struct option const long_options[] =
  47 {
  48   {"append", no_argument, NULL, 'a'},
  49   {"ignore-interrupts", no_argument, NULL, 'i'},
  50   {GETOPT_HELP_OPTION_DECL},
  51   {GETOPT_VERSION_OPTION_DECL},
  52   {NULL, 0, NULL, 0}
  53 };
  54
  55 void
  56 usage (int status)
  57 {
  58   if (status != 0)
  59     fprintf (stderr, _("Try `%s --help' for more information.\n"),
  60              program_name);
  61   else
  62     {
  63       printf (_("Usage: %s [OPTION]... [FILE]...\n"), program_name);
  64       fputs (_("\
  65 Copy standard input to each FILE, and also to standard output.\n\
  66 \n\
  67   -a, --append              append to the given FILEs, do not overwrite\n\
  68   -i, --ignore-interrupts   ignore interrupt signals\n\
  69 "), stdout);
  70       fputs (HELP_OPTION_DESCRIPTION, stdout);
  71       fputs (VERSION_OPTION_DESCRIPTION, stdout);
  72       printf (_("\nReport bugs to <%s>.\n"), PACKAGE_BUGREPORT);
  73     }
  74   exit (status);
  75 }
  76
  77 int
  78 main (int argc, char **argv)
  79 {
  80   int errs;
  81   int optc;
  82
  83   program_name = argv[0];
  84   setlocale (LC_ALL, "");
  85   bindtextdomain (PACKAGE, LOCALEDIR);
  86   textdomain (PACKAGE);
  87
  88   atexit (close_stdout);
  89
  90   append = 0;
  91   ignore_interrupts = 0;
  92
  93   while ((optc = getopt_long (argc, argv, "ai", long_options, NULL)) != -1)
  94     {
  95       switch (optc)
  96         {
  97         case 0:
  98           break;
  99
 100         case 'a':
 101           append = 1;
 102           break;
 103
 104         case 'i':
 105           ignore_interrupts = 1;
 106           break;
 107
 108         case_GETOPT_HELP_CHAR;
 109
 110         case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
 111
 112         default:
 113           usage (EXIT_FAILURE);
 114         }
 115     }
 116
 117   if (ignore_interrupts)
 118     {
 119 #ifdef _POSIX_SOURCE
 120       struct sigaction sigact;
 121
 122       sigact.sa_handler = SIG_IGN;
 123       sigemptyset (&sigact.sa_mask);
 124       sigact.sa_flags = 0;
 125       sigaction (SIGINT, &sigact, NULL);
 126 #else                           /* !_POSIX_SOURCE */
 127       signal (SIGINT, SIG_IGN);
 128 #endif                          /* _POSIX_SOURCE */
 129     }
 130
 131   /* Don't let us be killed if one of the output files is a pipe that
 132      doesn't consume all its input.  */
 133 #ifdef _POSIX_SOURCE
 134   {
 135     struct sigaction sigact;
 136
 137     sigact.sa_handler = SIG_IGN;
 138     sigemptyset (&sigact.sa_mask);
 139     sigact.sa_flags = 0;
 140     sigaction (SIGPIPE, &sigact, NULL);
 141   }
 142 #else
 143   signal (SIGPIPE, SIG_IGN);
 144 #endif
 145
 146   /* Do *not* warn if tee is given no file arguments.
 147      POSIX requires that it work when given no arguments.  */
 148
 149   errs = tee (argc - optind, (const char **) &argv[optind]);
 150   if (close (STDIN_FILENO) != 0)
 151     error (EXIT_FAILURE, errno, _("standard input"));
 152
 153   exit (errs);
 154 }
 155
 156 /* Copy the standard input into each of the NFILES files in FILES
 157    and into the standard output.
 158    Return 0 if successful, 1 if any errors occur. */
 159
 160 static int
 161 tee (int nfiles, const char **files)
 162 {
 163   FILE **descriptors;
 164   char buffer[BUFSIZ];
 165   int bytes_read, i;
 166   int ret = 0;
 167   const char *mode_string = (append ? "a" : "w");
 168
 169   descriptors = (FILE **) xmalloc ((nfiles + 1) * sizeof (descriptors[0]));
 170
 171   /* Move all the names `up' one in the argv array to make room for
 172      the entry for standard output.  This writes into argv[argc].  */
 173   for (i = nfiles; i >= 1; i--)
 174     files[i] = files[i - 1];
 175
 176   SET_BINARY2 (0, 1);
 177
 178   /* In the array of NFILES + 1 descriptors, make
 179      the first one correspond to standard output.   */
 180   descriptors[0] = stdout;
 181   files[0] = _("standard output");
 182   SETVBUF (stdout, NULL, _IONBF, 0);
 183
 184   for (i = 1; i <= nfiles; i++)
 185     {
 186       descriptors[i] = fopen (files[i], mode_string);
 187       if (descriptors[i] == NULL)
 188         {
 189           error (0, errno, "%s", files[i]);
 190           ret = 1;
 191         }
 192       else
 193         {
 194           SETVBUF (descriptors[i], NULL, _IONBF, 0);
 195           SET_BINARY (fileno (descriptors[i]));
 196         }
 197     }
 198
 199   while (1)
 200     {
 201       bytes_read = read (0, buffer, sizeof buffer);
 202 #ifdef EINTR
 203       if (bytes_read < 0 && errno == EINTR)
 204         continue;
 205 #endif
 206       if (bytes_read <= 0)
 207         break;
 208
 209       /* Write to all NFILES + 1 descriptors.
 210          Standard output is the first one.  */
 211       for (i = 0; i <= nfiles; i++)
 212         {
 213           if (descriptors[i] != NULL)
 214             fwrite (buffer, bytes_read, 1, descriptors[i]);
 215         }
 216     }
 217
 218   if (bytes_read == -1)
 219     {
 220       error (0, errno, _("read error"));
 221       ret = 1;
 222     }
 223
 224   /* Close the files, but not standard output.  */
 225   for (i = 1; i <= nfiles; i++)
 226     if (descriptors[i] != NULL
 227         && (ferror (descriptors[i]) || fclose (descriptors[i]) == EOF))
 228       {
 229         error (0, errno, "%s", files[i]);
 230         ret = 1;
 231       }
 232
 233   free (descriptors);
 234
 235   return ret;
 236 }