src/sum.c

   1 /* sum -- checksum and count the blocks in a file
   2    Copyright (C) 86, 89, 91, 95, 1996 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  17
  18 /* Like BSD sum or SysV sum -r, except like SysV sum if -s option is given. */
  19
  20 /* Written by Kayvan Aghaiepour and David MacKenzie. */
  21
  22 #include <config.h>
  23
  24 #include <stdio.h>
  25 #include <sys/types.h>
  26 #include <getopt.h>
  27 #include "system.h"
  28 #include "error.h"
  29
  30 int safe_read ();
  31
  32 /* The name this program was run with. */
  33 char *program_name;
  34
  35 /* Nonzero if any of the files read were the standard input. */
  36 static int have_read_stdin;
  37
  38 /* Right-rotate 32-bit integer variable C. */
  39 #define ROTATE_RIGHT(c) if ((c) & 01) (c) = ((c) >>1) + 0x8000; else (c) >>= 1;
  40
  41 /* If nonzero, display usage information and exit.  */
  42 static int show_help;
  43
  44 /* If nonzero, print the version on standard output then exit.  */
  45 static int show_version;
  46
  47 static struct option const longopts[] =
  48 {
  49   {"sysv", no_argument, NULL, 's'},
  50   {"help", no_argument, &show_help, 1},
  51   {"version", no_argument, &show_version, 1},
  52   {NULL, 0, NULL, 0}
  53 };
  54
  55 static 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 (_("\
  64 Usage: %s [OPTION]... [FILE]...\n\
  65 "),
  66               program_name);
  67       printf (_("\
  68 Print checksum and block counts for each FILE.\n\
  69 \n\
  70   -r              defeat -s, use BSD sum algorithm, use 1K blocks\n\
  71   -s, --sysv      use System V sum algorithm, use 512 bytes blocks\n\
  72       --help      display this help and exit\n\
  73       --version   output version information and exit\n\
  74 \n\
  75 With no FILE, or when FILE is -, read standard input.\n\
  76 "));
  77     }
  78   exit (status == 0 ? EXIT_SUCCESS : EXIT_FAILURE);
  79 }
  80
  81 /* Calculate and print the rotated checksum and the size in 1K blocks
  82    of file FILE, or of the standard input if FILE is "-".
  83    If PRINT_NAME is >1, print FILE next to the checksum and size.
  84    The checksum varies depending on sizeof(int).
  85    Return 0 if successful, -1 if an error occurs. */
  86
  87 static int
  88 bsd_sum_file (const char *file, int print_name)
  89 {
  90   register FILE *fp;
  91   register unsigned long checksum = 0; /* The checksum mod 2^16. */
  92   register long total_bytes = 0; /* The number of bytes. */
  93   register int ch;              /* Each character read. */
  94
  95   if (!strcmp (file, "-"))
  96     {
  97       fp = stdin;
  98       have_read_stdin = 1;
  99     }
 100   else
 101     {
 102       fp = fopen (file, "r");
 103       if (fp == NULL)
 104         {
 105           error (0, errno, "%s", file);
 106           return -1;
 107         }
 108     }
 109
 110   while ((ch = getc (fp)) != EOF)
 111     {
 112       total_bytes++;
 113       ROTATE_RIGHT (checksum);
 114       checksum += ch;
 115       checksum &= 0xffff;       /* Keep it within bounds. */
 116     }
 117
 118   if (ferror (fp))
 119     {
 120       error (0, errno, "%s", file);
 121       if (strcmp (file, "-"))
 122         fclose (fp);
 123       return -1;
 124     }
 125
 126   if (strcmp (file, "-") && fclose (fp) == EOF)
 127     {
 128       error (0, errno, "%s", file);
 129       return -1;
 130     }
 131
 132   printf ("%05lu %5ld", checksum, (total_bytes + 1024 - 1) / 1024);
 133   if (print_name > 1)
 134     printf (" %s", file);
 135   putchar ('\n');
 136
 137   return 0;
 138 }
 139
 140 /* Calculate and print the checksum and the size in 512-byte blocks
 141    of file FILE, or of the standard input if FILE is "-".
 142    If PRINT_NAME is >0, print FILE next to the checksum and size.
 143    Return 0 if successful, -1 if an error occurs. */
 144
 145 static int
 146 sysv_sum_file (const char *file, int print_name)
 147 {
 148   int fd;
 149   unsigned char buf[8192];
 150   register int bytes_read;
 151   register unsigned long checksum = 0;
 152   long total_bytes = 0;
 153
 154   if (!strcmp (file, "-"))
 155     {
 156       fd = 0;
 157       have_read_stdin = 1;
 158     }
 159   else
 160     {
 161       fd = open (file, O_RDONLY);
 162       if (fd == -1)
 163         {
 164           error (0, errno, "%s", file);
 165           return -1;
 166         }
 167     }
 168
 169   while ((bytes_read = safe_read (fd, buf, sizeof buf)) > 0)
 170     {
 171       register int i;
 172
 173       for (i = 0; i < bytes_read; i++)
 174         checksum += buf[i];
 175       total_bytes += bytes_read;
 176     }
 177
 178   if (bytes_read < 0)
 179     {
 180       error (0, errno, "%s", file);
 181       if (strcmp (file, "-"))
 182         close (fd);
 183       return -1;
 184     }
 185
 186   if (strcmp (file, "-") && close (fd) == -1)
 187     {
 188       error (0, errno, "%s", file);
 189       return -1;
 190     }
 191
 192   printf ("%lu %ld", checksum % 0xffff, (total_bytes + 512 - 1) / 512);
 193   if (print_name)
 194     printf (" %s", file);
 195   putchar ('\n');
 196
 197   return 0;
 198 }
 199
 200 int
 201 main (int argc, char **argv)
 202 {
 203   int errors = 0;
 204   int optc;
 205   int files_given;
 206   int (*sum_func) () = bsd_sum_file;
 207
 208   program_name = argv[0];
 209   setlocale (LC_ALL, "");
 210   bindtextdomain (PACKAGE, LOCALEDIR);
 211   textdomain (PACKAGE);
 212
 213   have_read_stdin = 0;
 214
 215   while ((optc = getopt_long (argc, argv, "rs", longopts, (int *) 0)) != -1)
 216     {
 217       switch (optc)
 218         {
 219         case 0:
 220           break;
 221
 222         case 'r':               /* For SysV compatibility. */
 223           sum_func = bsd_sum_file;
 224           break;
 225
 226         case 's':
 227           sum_func = sysv_sum_file;
 228           break;
 229
 230         default:
 231           usage (1);
 232         }
 233     }
 234
 235   if (show_version)
 236     {
 237       printf ("sum - %s\n", PACKAGE_VERSION);
 238       exit (EXIT_SUCCESS);
 239     }
 240
 241   if (show_help)
 242     usage (0);
 243
 244   files_given = argc - optind;
 245   if (files_given == 0)
 246     {
 247       if ((*sum_func) ("-", files_given) < 0)
 248         errors = 1;
 249     }
 250   else
 251     for (; optind < argc; optind++)
 252       if ((*sum_func) (argv[optind], files_given) < 0)
 253         errors = 1;
 254
 255   if (have_read_stdin && fclose (stdin) == EOF)
 256     error (EXIT_FAILURE, errno, "-");
 257   exit (errors == 0 ? EXIT_SUCCESS : EXIT_FAILURE);
 258 }
 259