lib-src/hexl.c

   1 /* Convert files for Emacs Hexl mode.
   2    Copyright (C) 1989, 2001-2024 Free Software Foundation, Inc.
   3
   4 Author: Keith Gabryelski (according to authors.el)
   5
   6 This file is not considered part of GNU Emacs.
   7
   8 This program is free software: you can redistribute it and/or modify
   9 it under the terms of the GNU General Public License as published by
  10 the Free Software Foundation, either version 3 of the License, or (at
  11 your option) any later version.
  12
  13 This program is distributed in the hope that it will be useful,
  14 but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 GNU General Public License for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  20
  21
  22 #include <config.h>
  23
  24 #include <inttypes.h>
  25 #include <stdlib.h>
  26 #include <string.h>
  27
  28 #include <binary-io.h>
  29 #include <unlocked-io.h>
  30
  31 static char *progname;
  32
  33 static _Noreturn void
  34 output_error (void)
  35 {
  36   fprintf (stderr, "%s: write error\n", progname);
  37   exit (EXIT_FAILURE);
  38 }
  39
  40 static int
  41 hexchar (int c)
  42 {
  43   return c - ('0' <= c && c <= '9' ? '0' : 'a' - 10);
  44 }
  45
  46 int
  47 main (int argc, char **argv)
  48 {
  49   int status = EXIT_SUCCESS;
  50   int DEFAULT_GROUPING = 0x01;
  51   int group_by = DEFAULT_GROUPING;
  52   bool un_flag = false, iso_flag = false;
  53   progname = *argv++;
  54
  55   /*
  56    ** -hex              hex dump
  57    ** -group-by-8-bits
  58    ** -group-by-16-bits
  59    ** -group-by-32-bits
  60    ** -group-by-64-bits
  61    ** -iso              iso character set.
  62    ** -un || -de        from hexl format to binary.
  63    ** --                End switch list.
  64    ** <filename>        dump filename
  65    ** -         (as filename == stdin)
  66    */
  67
  68   for (; *argv && *argv[0] == '-' && (*argv)[1]; argv++)
  69     {
  70       /* A switch! */
  71       if (!strcmp (*argv, "--"))
  72         {
  73           argv++;
  74           break;
  75         }
  76       else if (!strcmp (*argv, "-un") || !strcmp (*argv, "-de"))
  77         {
  78           un_flag = true;
  79           set_binary_mode (fileno (stdout), O_BINARY);
  80         }
  81       else if (!strcmp (*argv, "-hex"))
  82         /* Hex is the default and is only base supported.  */;
  83       else if (!strcmp (*argv, "-iso"))
  84         iso_flag = true;
  85       else if (!strcmp (*argv, "-group-by-8-bits"))
  86         group_by = 0x00;
  87       else if (!strcmp (*argv, "-group-by-16-bits"))
  88         group_by = 0x01;
  89       else if (!strcmp (*argv, "-group-by-32-bits"))
  90         group_by = 0x03;
  91       else if (!strcmp (*argv, "-group-by-64-bits"))
  92         group_by = 0x07;
  93       else
  94         {
  95           fprintf (stderr, "%s: invalid switch: \"%s\".\n", progname,
  96                    *argv);
  97           fprintf (stderr, "usage: %s [-de] [-iso]\n", progname);
  98           return EXIT_FAILURE;
  99         }
 100     }
 101
 102   char const *filename = *argv ? *argv++ : "-";
 103
 104   do
 105     {
 106       FILE *fp;
 107
 108       if (!strcmp (filename, "-"))
 109         {
 110           fp = stdin;
 111           if (!un_flag)
 112             set_binary_mode (fileno (stdin), O_BINARY);
 113         }
 114       else
 115         {
 116           fp = fopen (filename, un_flag ? "r" : "rb");
 117           if (!fp)
 118             {
 119               perror (filename);
 120               status = EXIT_FAILURE;
 121               continue;
 122             }
 123         }
 124
 125       if (un_flag)
 126         {
 127           for (int c; 0 <= (c = getc (fp)); )
 128             {
 129               /* Skip address at start of line.  */
 130               if (c != ' ')
 131                 continue;
 132
 133               for (int i = 0; i < 16; i++)
 134                 {
 135                   c = getc (fp);
 136                   if (c < 0 || c == ' ')
 137                     break;
 138
 139                   int hc = hexchar (c);
 140                   c = getc (fp);
 141                   if (c < 0)
 142                     break;
 143                   putchar (hc * 0x10 + hexchar (c));
 144
 145                   if ((i & group_by) == group_by)
 146                     {
 147                       c = getc (fp);
 148                       if (c < 0)
 149                         break;
 150                     }
 151                 }
 152
 153               while (0 <= c && c != '\n')
 154                 c = getc (fp);
 155               if (c < 0)
 156                 break;
 157               if (ferror (stdout))
 158                 output_error ();
 159             }
 160         }
 161       else
 162         {
 163           int c = 0;
 164           char string[18];
 165           string[0] = ' ';
 166           string[17] = '\0';
 167           for (uintmax_t address = 0; 0 <= c; address += 0x10)
 168             {
 169               int i;
 170               for (i = 0; i < 16; i++)
 171                 {
 172                   if (0 <= c)
 173                     c = getc (fp);
 174                   if (c < 0)
 175                     {
 176                       if (!i)
 177                         break;
 178
 179                       fputs ("  ", stdout);
 180                       string[i + 1] = '\0';
 181                     }
 182                   else
 183                     {
 184                       if (!i)
 185                         printf ("%08"PRIxMAX": ", address);
 186
 187                       string[i + 1]
 188                         = (c < 0x20 || (0x7F <= c && (!iso_flag || c < 0xa0))
 189                            ? '.' : c);
 190
 191                       printf ("%02x", c + 0u);
 192                     }
 193
 194                   if ((i & group_by) == group_by)
 195                     putchar (' ');
 196                 }
 197
 198               if (i)
 199                 puts (string);
 200
 201               if (ferror (stdout))
 202                 output_error ();
 203             }
 204         }
 205
 206       bool trouble = ferror (fp) != 0;
 207       trouble |= fp != stdin && fclose (fp) != 0;
 208       if (trouble)
 209         {
 210           fprintf (stderr, "%s: read error\n", progname);
 211           status = EXIT_FAILURE;
 212         }
 213
 214       filename = *argv++;
 215     }
 216   while (filename);
 217
 218   if (ferror (stdout) || fclose (stdout) != 0)
 219     output_error ();
 220   return status;
 221 }