usr.bin/dc/dc.c

   1 /*
   2  * $OpenBSD: dc.c,v 1.5 2004/01/13 08:17:41 otto Exp $
   3  * $DragonFly: src/usr.bin/dc/dc.c,v 1.1 2004/09/20 04:20:39 dillon Exp $
   4  */
   5
   6 /*
   7  * Copyright (c) 2003, Otto Moerbeek <otto@drijf.net>
   8  *
   9  * Permission to use, copy, modify, and distribute this software for any
  10  * purpose with or without fee is hereby granted, provided that the above
  11  * copyright notice and this permission notice appear in all copies.
  12  *
  13  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  14  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  15  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  16  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  17  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  18  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  19  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  20  */
  21
  22 #include <err.h>
  23 #include <stdlib.h>
  24 #include <unistd.h>
  25
  26 #include "extern.h"
  27
  28 static void             usage(void);
  29
  30 extern char             *__progname;
  31
  32 static void
  33 usage(void)
  34 {
  35         fprintf(stderr, "usage: %s [-x] [file]\n", __progname);
  36         exit(1);
  37 }
  38
  39 int
  40 main(int argc, char *argv[])
  41 {
  42         int             ch;
  43         bool            extended_regs = false;
  44         FILE            *file;
  45         struct source   src;
  46
  47         /* accept and ignore a single dash to be 4.4BSD dc(1) compatible */
  48         while ((ch = getopt(argc, argv, "x-")) != -1) {
  49                 switch (ch) {
  50                 case 'x':
  51                         extended_regs = true;
  52                         break;
  53                 case '-':
  54                         break;
  55                 default:
  56                         usage();
  57                 }
  58         }
  59         argc -= optind;
  60         argv += optind;
  61
  62         init_bmachine(extended_regs);
  63         setlinebuf(stdout);
  64         setlinebuf(stderr);
  65
  66         if (argc > 1)
  67                 usage();
  68         else if (argc == 1) {
  69                 file = fopen(argv[0], "r");
  70                 if (file == NULL)
  71                         err(1, "cannot open file %s", argv[0]);
  72                 src_setstream(&src, file);
  73                 reset_bmachine(&src);
  74                 eval();
  75                 fclose(file);
  76         }
  77         /*
  78          * BSD dc and Solaris dc continue with stdin after processing
  79          * the file given as the argument.
  80          */
  81         src_setstream(&src, stdin);
  82         reset_bmachine(&src);
  83         eval();
  84
  85         return 0;
  86 }