gnu/dist/bc/dc/dc.c

   1 /*
   2  * implement the "dc" Desk Calculator language.
   3  *
   4  * Copyright (C) 1994, 1997, 1998, 2000 Free Software Foundation, Inc.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2, or (at your option)
   9  * any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, you can either send email to this
  18  * program's author (see below) or write to:
  19  *   The Free Software Foundation, Inc.
  20  *   59 Temple Place, Suite 330
  21  *   Boston, MA 02111 USA
  22  */
  23
  24 /* Written with strong hiding of implementation details
  25  * in their own specialized modules.
  26  */
  27 /* This module contains the argument processing/main functions.
  28  */
  29
  30 #include "config.h"
  31
  32 #include <stdio.h>
  33 #ifdef HAVE_STDLIB_H
  34 # include <stdlib.h>
  35 #endif
  36 #ifdef HAVE_STRING_H
  37 # include <string.h>
  38 #else
  39 # ifdef HAVE_STRINGS_H
  40 #  include <strings.h>
  41 # endif
  42 #endif
  43 #include <getopt.h>
  44 #include <sys/types.h>
  45 #include <sys/stat.h>
  46 #include <errno.h>
  47 #include "dc.h"
  48 #include "dc-proto.h"
  49
  50 #ifndef EXIT_SUCCESS    /* C89 <stdlib.h> */
  51 # define EXIT_SUCCESS   0
  52 #endif
  53 #ifndef EXIT_FAILURE    /* C89 <stdlib.h> */
  54 # define EXIT_FAILURE   1
  55 #endif
  56
  57 const char *progname;   /* basename of program invocation */
  58
  59 static void
  60 bug_report_info DC_DECLVOID()
  61 {
  62         printf("Email bug reports to:  bug-dc@gnu.org .\n");
  63 }
  64
  65 static void
  66 show_version DC_DECLVOID()
  67 {
  68         printf("dc (GNU %s %s) %s\n", PACKAGE, VERSION, DC_VERSION);
  69         printf("\n%s\n\
  70 This is free software; see the source for copying conditions.  There is NO\n\
  71 warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE,\n\
  72 to the extent permitted by law.\n", DC_COPYRIGHT);
  73 }
  74
  75 /* your generic usage function */
  76 static void
  77 usage DC_DECLARG((f))
  78         FILE *f DC_DECLEND
  79 {
  80         fprintf(f, "\
  81 Usage: %s [OPTION] [file ...]\n\
  82   -e, --expression=EXPR    evaluate expression\n\
  83   -f, --file=FILE          evaluate contents of file\n\
  84   -h, --help               display this help and exit\n\
  85   -V, --version            output version information and exit\n\
  86 \n\
  87 ", progname);
  88         bug_report_info();
  89 }
  90
  91 /* returns a pointer to one past the last occurance of c in s,
  92  * or s if c does not occur in s.
  93  */
  94 static char *
  95 r1bindex DC_DECLARG((s, c))
  96         char *s DC_DECLSEP
  97         int  c DC_DECLEND
  98 {
  99         char *p = strrchr(s, c);
 100
 101         if (!p)
 102                 return s;
 103         return p + 1;
 104 }
 105
 106 static void
 107 try_file(const char *filename)
 108 {
 109         FILE *input;
 110
 111         if (strcmp(filename, "-") == 0) {
 112                 input = stdin;
 113         } else {
 114                 struct stat sb;
 115                 if (stat(filename, &sb) < 0) {
 116                         fprintf(stderr, "Cannot stat %s: %s\n",
 117                                 filename, strerror(errno));
 118                         exit(EXIT_FAILURE);
 119                 }
 120                 if (S_ISDIR(sb.st_mode)) {
 121                         fprintf(stderr, "Cannot use directory as input!\n");
 122                         exit(EXIT_FAILURE);
 123                 }
 124                 if ( !(input=fopen(filename, "r")) ) {
 125                         fprintf(stderr, "Could not open file ");
 126                         perror(filename);
 127                         exit(EXIT_FAILURE);
 128                 }
 129         }
 130         if (dc_evalfile(input))
 131                 exit(EXIT_FAILURE);
 132         if (input != stdin)
 133                 fclose(input);
 134 }
 135
 136 \f
 137 int
 138 main DC_DECLARG((argc, argv))
 139         int  argc DC_DECLSEP
 140         char **argv DC_DECLEND
 141 {
 142         static struct option const long_opts[] = {
 143                 {"expression", required_argument, NULL, 'e'},
 144                 {"file", required_argument, NULL, 'f'},
 145                 {"help", no_argument, NULL, 'h'},
 146                 {"version", no_argument, NULL, 'V'},
 147                 {NULL, 0, NULL, 0}
 148         };
 149         int did_eval = 0;
 150         int c;
 151
 152         progname = r1bindex(*argv, '/');
 153 #ifdef HAVE_SETVBUF
 154         /* attempt to simplify interaction with applications such as emacs */
 155         (void) setvbuf(stdout, NULL, _IOLBF, 0);
 156 #endif
 157         dc_math_init();
 158         dc_string_init();
 159         dc_register_init();
 160         dc_array_init();
 161
 162         while ((c = getopt_long(argc, argv, "hVe:f:", long_opts, (int *)0)) != EOF) {
 163                 switch (c) {
 164                 case 'e':
 165                         {       dc_data string = dc_makestring(optarg, strlen(optarg));
 166                                 if (dc_evalstr(string))
 167                                         return EXIT_SUCCESS;
 168                                 dc_free_str(&string.v.string);
 169                                 did_eval = 1;
 170                         }
 171                         break;
 172                 case 'f':
 173                         try_file(optarg);
 174                         did_eval = 1;
 175                         break;
 176                 case 'h':
 177                         usage(stdout);
 178                         return EXIT_SUCCESS;
 179                 case 'V':
 180                         show_version();
 181                         return EXIT_SUCCESS;
 182                 default:
 183                         usage(stderr);
 184                         return EXIT_FAILURE;
 185                 }
 186         }
 187
 188         for (; optind < argc; ++optind) {
 189                 try_file(argv[optind]);
 190                 did_eval = 1;
 191         }
 192         if (!did_eval) {
 193                 /* if no -e commands and no command files, then eval stdin */
 194                 if (dc_evalfile(stdin))
 195                         return EXIT_FAILURE;
 196         }
 197         return EXIT_SUCCESS;
 198 }