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/* This file is part of GNU tar test suite
Copyright (C) 2004 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 2, 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, write to the Free Software Foundation, Inc.,
59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <stdarg.h>
#include <fcntl.h>
#include <string.h>
char *progname;
char *buffer;
size_t buffer_size;
static void die (char const *, ...) __attribute__ ((noreturn,
format (printf, 1, 2)));
static void
die (char const *fmt, ...)
{
va_list ap;
fprintf (stderr, "%s: ", progname);
va_start (ap, fmt);
vfprintf (stderr, fmt, ap);
va_end (ap);
fprintf (stderr, "\n");
exit (1);
}
static void
mkhole (int fd, off_t displ)
{
if (lseek (fd, displ, SEEK_CUR) == -1)
{
perror ("lseek");
exit (1);
}
ftruncate (fd, lseek (fd, 0, SEEK_CUR));
}
static void
mksparse (int fd, off_t displ, char *marks)
{
for (; *marks; marks++)
{
memset (buffer, *marks, buffer_size);
if (write(fd, buffer, buffer_size) != buffer_size)
{
perror ("write");
exit (1);
}
if (lseek (fd, displ, SEEK_CUR) == -1)
{
perror ("lseek");
exit (1);
}
}
}
static void usage (void) __attribute__ ((noreturn));
static void
usage (void)
{
printf ("Usage: mksparse filename blocksize disp letters [disp letters...] [disp]\n");
exit (1);
}
static int
xlat_suffix (off_t *vp, char *p)
{
if (p[1])
return 1;
switch (p[0])
{
case 'g':
case 'G':
*vp *= 1024;
case 'm':
case 'M':
*vp *= 1024;
case 'k':
case 'K':
*vp *= 1024;
break;
default:
return 1;
}
return 0;
}
int
main (int argc, char **argv)
{
int i;
int fd;
char *p;
off_t n;
progname = strrchr (argv[0], '/');
if (progname)
progname++;
else
progname = argv[0];
if (argc < 4)
usage ();
fd = open (argv[1], O_CREAT|O_TRUNC|O_RDWR, 0644);
if (fd < 0)
die ("cannot open %s", argv[1]);
n = strtoul (argv[2], &p, 0);
if (n <= 0 || (*p && xlat_suffix (&n, p)))
die ("Invalid buffer size: %s", argv[2]);
buffer_size = n;
buffer = malloc (buffer_size);
if (!buffer)
die ("Not enough memory");
for (i = 3; i < argc; i += 2)
{
off_t displ;
displ = strtoul (argv[i], &p, 0);
if (displ < 0 || (*p && xlat_suffix (&displ, p)))
die ("Invalid displacement: %s", argv[i]);
if (i == argc-1)
{
mkhole (fd, displ);
break;
}
else
mksparse (fd, displ, argv[i+1]);
}
close(fd);
return 0;
}
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