/* sum -- checksum and count the blocks in a file
Copyright (C) 1986-2015 Free Software Foundation, Inc.
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see . */
/* Like BSD sum or SysV sum -r, except like SysV sum if -s option is given. */
/* Written by Kayvan Aghaiepour and David MacKenzie. */
#include
#include
#include
#include
#include "system.h"
#include "error.h"
#include "fadvise.h"
#include "human.h"
#include "quote.h"
#include "safe-read.h"
#include "xfreopen.h"
/* The official name of this program (e.g., no 'g' prefix). */
#define PROGRAM_NAME "sum"
#define AUTHORS \
proper_name ("Kayvan Aghaiepour"), \
proper_name ("David MacKenzie")
/* True if any of the files read were the standard input. */
static bool have_read_stdin;
static struct option const longopts[] =
{
{"sysv", no_argument, NULL, 's'},
{GETOPT_HELP_OPTION_DECL},
{GETOPT_VERSION_OPTION_DECL},
{NULL, 0, NULL, 0}
};
void
usage (int status)
{
if (status != EXIT_SUCCESS)
emit_try_help ();
else
{
printf (_("\
Usage: %s [OPTION]... [FILE]...\n\
"),
program_name);
fputs (_("\
Print checksum and block counts for each FILE.\n\
"), stdout);
emit_stdin_note ();
fputs (_("\
\n\
-r use BSD sum algorithm, use 1K blocks\n\
-s, --sysv use System V sum algorithm, use 512 bytes blocks\n\
"), stdout);
fputs (HELP_OPTION_DESCRIPTION, stdout);
fputs (VERSION_OPTION_DESCRIPTION, stdout);
emit_ancillary_info (PROGRAM_NAME);
}
exit (status);
}
/* Calculate and print the rotated checksum and the size in 1K blocks
of file FILE, or of the standard input if FILE is "-".
If PRINT_NAME is >1, print FILE next to the checksum and size.
The checksum varies depending on sizeof (int).
Return true if successful. */
static bool
bsd_sum_file (const char *file, int print_name)
{
FILE *fp;
int checksum = 0; /* The checksum mod 2^16. */
uintmax_t total_bytes = 0; /* The number of bytes. */
int ch; /* Each character read. */
char hbuf[LONGEST_HUMAN_READABLE + 1];
bool is_stdin = STREQ (file, "-");
if (is_stdin)
{
fp = stdin;
have_read_stdin = true;
if (O_BINARY && ! isatty (STDIN_FILENO))
xfreopen (NULL, "rb", stdin);
}
else
{
fp = fopen (file, (O_BINARY ? "rb" : "r"));
if (fp == NULL)
{
error (0, errno, "%s", quote (file));
return false;
}
}
fadvise (fp, FADVISE_SEQUENTIAL);
while ((ch = getc (fp)) != EOF)
{
total_bytes++;
checksum = (checksum >> 1) + ((checksum & 1) << 15);
checksum += ch;
checksum &= 0xffff; /* Keep it within bounds. */
}
if (ferror (fp))
{
error (0, errno, "%s", quote (file));
if (!is_stdin)
fclose (fp);
return false;
}
if (!is_stdin && fclose (fp) != 0)
{
error (0, errno, "%s", quote (file));
return false;
}
printf ("%05d %5s", checksum,
human_readable (total_bytes, hbuf, human_ceiling, 1, 1024));
if (print_name > 1)
printf (" %s", file);
putchar ('\n');
return true;
}
/* Calculate and print the checksum and the size in 512-byte blocks
of file FILE, or of the standard input if FILE is "-".
If PRINT_NAME is >0, print FILE next to the checksum and size.
Return true if successful. */
static bool
sysv_sum_file (const char *file, int print_name)
{
int fd;
unsigned char buf[8192];
uintmax_t total_bytes = 0;
char hbuf[LONGEST_HUMAN_READABLE + 1];
int r;
int checksum;
/* The sum of all the input bytes, modulo (UINT_MAX + 1). */
unsigned int s = 0;
bool is_stdin = STREQ (file, "-");
if (is_stdin)
{
fd = STDIN_FILENO;
have_read_stdin = true;
if (O_BINARY && ! isatty (STDIN_FILENO))
xfreopen (NULL, "rb", stdin);
}
else
{
fd = open (file, O_RDONLY | O_BINARY);
if (fd == -1)
{
error (0, errno, "%s", quote (file));
return false;
}
}
while (1)
{
size_t i;
size_t bytes_read = safe_read (fd, buf, sizeof buf);
if (bytes_read == 0)
break;
if (bytes_read == SAFE_READ_ERROR)
{
error (0, errno, "%s", quote (file));
if (!is_stdin)
close (fd);
return false;
}
for (i = 0; i < bytes_read; i++)
s += buf[i];
total_bytes += bytes_read;
}
if (!is_stdin && close (fd) != 0)
{
error (0, errno, "%s", quote (file));
return false;
}
r = (s & 0xffff) + ((s & 0xffffffff) >> 16);
checksum = (r & 0xffff) + (r >> 16);
printf ("%d %s", checksum,
human_readable (total_bytes, hbuf, human_ceiling, 1, 512));
if (print_name)
printf (" %s", file);
putchar ('\n');
return true;
}
int
main (int argc, char **argv)
{
bool ok;
int optc;
int files_given;
bool (*sum_func) (const char *, int) = bsd_sum_file;
initialize_main (&argc, &argv);
set_program_name (argv[0]);
setlocale (LC_ALL, "");
bindtextdomain (PACKAGE, LOCALEDIR);
textdomain (PACKAGE);
atexit (close_stdout);
/* Line buffer stdout to ensure lines are written atomically and immediately
so that processes running in parallel do not intersperse their output. */
setvbuf (stdout, NULL, _IOLBF, 0);
have_read_stdin = false;
while ((optc = getopt_long (argc, argv, "rs", longopts, NULL)) != -1)
{
switch (optc)
{
case 'r': /* For SysV compatibility. */
sum_func = bsd_sum_file;
break;
case 's':
sum_func = sysv_sum_file;
break;
case_GETOPT_HELP_CHAR;
case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
default:
usage (EXIT_FAILURE);
}
}
files_given = argc - optind;
if (files_given <= 0)
ok = sum_func ("-", files_given);
else
for (ok = true; optind < argc; optind++)
ok &= sum_func (argv[optind], files_given);
if (have_read_stdin && fclose (stdin) == EOF)
error (EXIT_FAILURE, errno, "%s", quote ("-"));
return ok ? EXIT_SUCCESS : EXIT_FAILURE;
}