src/tee.c

   1 /* tee - read from standard input and write to standard output and files.
   2    Copyright (C) 85, 90, 91, 92, 93, 94, 1995 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
  16    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, 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 "version.h"
  28 #include "error.h"
  29
  30 char *xmalloc ();
  31 int full_write ();
  32
  33 static int tee __P ((int nfiles, const char **files));
  34
  35 /* If nonzero, append to output files rather than truncating them. */
  36 static int append;
  37
  38 /* If nonzero, ignore interrupts. */
  39 static int ignore_interrupts;
  40
  41 /* The name that this program was run with. */
  42 char *program_name;
  43
  44 /* If nonzero, display usage information and exit.  */
  45 static int show_help;
  46
  47 /* If nonzero, print the version on standard output and exit.  */
  48 static int show_version;
  49
  50 static struct option const long_options[] =
  51 {
  52   {"append", no_argument, NULL, 'a'},
  53   {"help", no_argument, &show_help, 1},
  54   {"ignore-interrupts", no_argument, NULL, 'i'},
  55   {"version", no_argument, &show_version, 1},
  56   {NULL, 0, NULL, 0}
  57 };
  58
  59 static void
  60 usage (int status)
  61 {
  62   if (status != 0)
  63     fprintf (stderr, _("Try `%s --help' for more information.\n"),
  64              program_name);
  65   else
  66     {
  67       printf (_("Usage: %s [OPTION]... [FILE]...\n"), program_name);
  68       printf (_("\
  69 Copy standard input to each FILE, and also to standard output.\n\
  70 \n\
  71   -a, --append              append to the given FILEs, do not overwrite\n\
  72   -i, --ignore-interrupts   ignore interrupt signals\n\
  73       --help                display this help and exit\n\
  74       --version             output version information and exit\n\
  75 "));
  76     }
  77   exit (status);
  78 }
  79
  80 void
  81 main (int argc, char **argv)
  82 {
  83   int errs;
  84   int optc;
  85
  86   program_name = argv[0];
  87   append = 0;
  88   ignore_interrupts = 0;
  89
  90   while ((optc = getopt_long (argc, argv, "ai", long_options, (int *) 0))
  91          != EOF)
  92     {
  93       switch (optc)
  94         {
  95         case 0:
  96           break;
  97
  98         case 'a':
  99           append = 1;
 100           break;
 101
 102         case 'i':
 103           ignore_interrupts = 1;
 104           break;
 105
 106         default:
 107           usage (1);
 108         }
 109     }
 110
 111   if (show_version)
 112     {
 113       printf ("tee - %s\n", version_string);
 114       exit (0);
 115     }
 116
 117   if (show_help)
 118     usage (0);
 119
 120   if (ignore_interrupts)
 121     {
 122 #ifdef _POSIX_SOURCE
 123       struct sigaction sigact;
 124
 125       sigact.sa_handler = SIG_IGN;
 126       sigemptyset (&sigact.sa_mask);
 127       sigact.sa_flags = 0;
 128       sigaction (SIGINT, &sigact, NULL);
 129 #else                           /* !_POSIX_SOURCE */
 130       signal (SIGINT, SIG_IGN);
 131 #endif                          /* _POSIX_SOURCE */
 132     }
 133
 134   errs = tee (argc - optind, (const char **) &argv[optind]);
 135   if (close (0) != 0)
 136     error (1, errno, _("standard input"));
 137   if (close (1) != 0)
 138     error (1, errno, _("standard output"));
 139   exit (errs);
 140 }
 141
 142 /* Copy the standard input into each of the NFILES files in FILES
 143    and into the standard output.
 144    Return 0 if successful, 1 if any errors occur. */
 145
 146 static int
 147 tee (int nfiles, const char **files)
 148 {
 149   int *descriptors;
 150   char buffer[BUFSIZ];
 151   register int bytes_read, i, ret = 0, mode;
 152
 153   descriptors = (int *) xmalloc ((nfiles + 1) * sizeof (int));
 154
 155   mode = O_WRONLY | O_CREAT;
 156   if (append)
 157     mode |= O_APPEND;
 158   else
 159     mode |= O_TRUNC;
 160
 161   /* Move all the names `up' one in the argv array to make room for
 162      the entry for standard output.  This writes into argv[argc].  */
 163   for (i = nfiles; i >= 1; i--)
 164     files[i] = files[i - 1];
 165
 166   /* In the array of NFILES + 1 descriptors, make
 167      the first one correspond to standard output.   */
 168   descriptors[0] = 1;
 169   files[0] = _("standard output");
 170
 171   for (i = 1; i <= nfiles; i++)
 172     {
 173       descriptors[i] = open (files[i], mode, 0666);
 174       if (descriptors[i] == -1)
 175         {
 176           error (0, errno, "%s", files[i]);
 177           ret = 1;
 178         }
 179     }
 180
 181   while (1)
 182     {
 183       bytes_read = read (0, buffer, sizeof buffer);
 184 #ifdef EINTR
 185       if (bytes_read < 0 && errno == EINTR)
 186         continue;
 187 #endif
 188       if (bytes_read <= 0)
 189         break;
 190
 191       /* Write to all NFILES + 1 descriptors.
 192          Standard output is the first one.  */
 193       for (i = 0; i <= nfiles; i++)
 194         {
 195           if (descriptors[i] != -1
 196               && full_write (descriptors[i], buffer, bytes_read) < 0)
 197             {
 198               error (0, errno, "%s", files[i]);
 199               /* Don't close stdout.  That's done in main.  */
 200               if (descriptors[i] != 1)
 201                 close (descriptors[i]);
 202               descriptors[i] = -1;
 203               ret = 1;
 204             }
 205         }
 206     }
 207
 208   if (bytes_read == -1)
 209     {
 210       error (0, errno, _("read error"));
 211       ret = 1;
 212     }
 213
 214   /* Close the files, but not standard output.  */
 215   for (i = 1; i <= nfiles; i++)
 216     if (descriptors[i] != -1 && close (descriptors[i]) != 0)
 217       {
 218         error (0, errno, "%s", files[i]);
 219         ret = 1;
 220       }
 221
 222   free (descriptors);
 223
 224   return ret;
 225 }