src/sum.c

   1 /* sum -- checksum and count the blocks in a file
   2    Copyright (C) 86, 89, 91, 1995-2001 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 Foundation,
  16    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 "closeout.h"
  29 #include "error.h"
  30 #include "human.h"
  31 #include "safe-read.h"
  32
  33 /* The official name of this program (e.g., no `g' prefix).  */
  34 #define PROGRAM_NAME "sum"
  35
  36 #define AUTHORS N_ ("Kayvan Aghaiepour and David MacKenzie")
  37
  38 /* The name this program was run with. */
  39 char *program_name;
  40
  41 /* Nonzero if any of the files read were the standard input. */
  42 static int have_read_stdin;
  43
  44 static struct option const longopts[] =
  45 {
  46   {"sysv", no_argument, NULL, 's'},
  47   {GETOPT_HELP_OPTION_DECL},
  48   {GETOPT_VERSION_OPTION_DECL},
  49   {NULL, 0, NULL, 0}
  50 };
  51
  52 void
  53 usage (int status)
  54 {
  55   if (status != 0)
  56     fprintf (stderr, _("Try `%s --help' for more information.\n"),
  57              program_name);
  58   else
  59     {
  60       printf (_("\
  61 Usage: %s [OPTION]... [FILE]...\n\
  62 "),
  63               program_name);
  64       fputs (_("\
  65 Print checksum and block counts for each FILE.\n\
  66 \n\
  67   -r              defeat -s, use BSD sum algorithm, use 1K blocks\n\
  68   -s, --sysv      use System V sum algorithm, use 512 bytes blocks\n\
  69 "), stdout);
  70       fputs (HELP_OPTION_DESCRIPTION, stdout);
  71       fputs (VERSION_OPTION_DESCRIPTION, stdout);
  72       fputs (_("\
  73 \n\
  74 With no FILE, or when FILE is -, read standard input.\n\
  75 "), stdout);
  76       printf (_("\nReport bugs to <%s>.\n"), PACKAGE_BUGREPORT);
  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 int checksum = 0;    /* The checksum mod 2^16. */
  92   register uintmax_t total_bytes = 0;   /* The number of bytes. */
  93   register int ch;              /* Each character read. */
  94   char hbuf[LONGEST_HUMAN_READABLE + 1];
  95
  96   if (STREQ (file, "-"))
  97     {
  98       fp = stdin;
  99       have_read_stdin = 1;
 100     }
 101   else
 102     {
 103       fp = fopen (file, "r");
 104       if (fp == NULL)
 105         {
 106           error (0, errno, "%s", file);
 107           return -1;
 108         }
 109     }
 110   /* Need binary I/O, or else byte counts and checksums are incorrect.  */
 111   SET_BINARY (fileno(fp));
 112
 113   while ((ch = getc (fp)) != EOF)
 114     {
 115       total_bytes++;
 116       checksum = (checksum >> 1) + ((checksum & 1) << 15);
 117       checksum += ch;
 118       checksum &= 0xffff;       /* Keep it within bounds. */
 119     }
 120
 121   if (ferror (fp))
 122     {
 123       error (0, errno, "%s", file);
 124       if (!STREQ (file, "-"))
 125         fclose (fp);
 126       return -1;
 127     }
 128
 129   if (!STREQ (file, "-") && fclose (fp) == EOF)
 130     {
 131       error (0, errno, "%s", file);
 132       return -1;
 133     }
 134
 135   printf ("%05d %5s", checksum,
 136           human_readable_inexact (total_bytes, hbuf, 1, 1024, human_ceiling));
 137   if (print_name > 1)
 138     printf (" %s", file);
 139   putchar ('\n');
 140
 141   return 0;
 142 }
 143
 144 /* Calculate and print the checksum and the size in 512-byte blocks
 145    of file FILE, or of the standard input if FILE is "-".
 146    If PRINT_NAME is >0, print FILE next to the checksum and size.
 147    Return 0 if successful, -1 if an error occurs. */
 148
 149 static int
 150 sysv_sum_file (const char *file, int print_name)
 151 {
 152   int fd;
 153   unsigned char buf[8192];
 154   register int bytes_read;
 155   uintmax_t total_bytes = 0;
 156   char hbuf[LONGEST_HUMAN_READABLE + 1];
 157   int r;
 158   int checksum;
 159
 160   /* The sum of all the input bytes, modulo (UINT_MAX + 1).  */
 161   register unsigned int s = 0;
 162
 163   if (STREQ (file, "-"))
 164     {
 165       fd = 0;
 166       have_read_stdin = 1;
 167     }
 168   else
 169     {
 170       fd = open (file, O_RDONLY);
 171       if (fd == -1)
 172         {
 173           error (0, errno, "%s", file);
 174           return -1;
 175         }
 176     }
 177   /* Need binary I/O, or else byte counts and checksums are incorrect.  */
 178   SET_BINARY (fd);
 179
 180   while ((bytes_read = safe_read (fd, buf, sizeof buf)) > 0)
 181     {
 182       register int i;
 183
 184       for (i = 0; i < bytes_read; i++)
 185         s += buf[i];
 186       total_bytes += bytes_read;
 187     }
 188
 189   if (bytes_read < 0)
 190     {
 191       error (0, errno, "%s", file);
 192       if (!STREQ (file, "-"))
 193         close (fd);
 194       return -1;
 195     }
 196
 197   if (!STREQ (file, "-") && close (fd) == -1)
 198     {
 199       error (0, errno, "%s", file);
 200       return -1;
 201     }
 202
 203   r = (s & 0xffff) + ((s & 0xffffffff) >> 16);
 204   checksum = (r & 0xffff) + (r >> 16);
 205
 206   printf ("%d %s", checksum,
 207           human_readable_inexact (total_bytes, hbuf, 1, 512, human_ceiling));
 208   if (print_name)
 209     printf (" %s", file);
 210   putchar ('\n');
 211
 212   return 0;
 213 }
 214
 215 int
 216 main (int argc, char **argv)
 217 {
 218   int errors = 0;
 219   int optc;
 220   int files_given;
 221   int (*sum_func) PARAMS ((const char *, int)) = bsd_sum_file;
 222
 223   program_name = argv[0];
 224   setlocale (LC_ALL, "");
 225   bindtextdomain (PACKAGE, LOCALEDIR);
 226   textdomain (PACKAGE);
 227
 228   atexit (close_stdout);
 229
 230   have_read_stdin = 0;
 231
 232   while ((optc = getopt_long (argc, argv, "rs", longopts, NULL)) != -1)
 233     {
 234       switch (optc)
 235         {
 236         case 0:
 237           break;
 238
 239         case 'r':               /* For SysV compatibility. */
 240           sum_func = bsd_sum_file;
 241           break;
 242
 243         case 's':
 244           sum_func = sysv_sum_file;
 245           break;
 246
 247         case_GETOPT_HELP_CHAR;
 248
 249         case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
 250
 251         default:
 252           usage (1);
 253         }
 254     }
 255
 256   files_given = argc - optind;
 257   if (files_given == 0)
 258     {
 259       if ((*sum_func) ("-", files_given) < 0)
 260         errors = 1;
 261     }
 262   else
 263     for (; optind < argc; optind++)
 264       if ((*sum_func) (argv[optind], files_given) < 0)
 265         errors = 1;
 266
 267   if (have_read_stdin && fclose (stdin) == EOF)
 268     error (EXIT_FAILURE, errno, "-");
 269   exit (errors == 0 ? EXIT_SUCCESS : EXIT_FAILURE);
 270 }