grub/grub-core/commands/crc.c
2010-05-06 11:34:04 +05:30

71 lines
1.8 KiB
C

/* crc.c - command to calculate the crc32 checksum of a file */
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2008,2010 Free Software Foundation, Inc.
*
* GRUB 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.
*
* GRUB 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 GRUB. If not, see <http://www.gnu.org/licenses/>.
*/
#include <grub/dl.h>
#include <grub/disk.h>
#include <grub/file.h>
#include <grub/misc.h>
#include <grub/lib/crc.h>
#include <grub/command.h>
#include <grub/i18n.h>
static grub_err_t
grub_cmd_crc (grub_command_t cmd __attribute__ ((unused)),
int argc, char **args)
{
grub_file_t file;
char buf[GRUB_DISK_SECTOR_SIZE];
grub_ssize_t size;
grub_uint32_t crc;
if (argc != 1)
return grub_error (GRUB_ERR_BAD_ARGUMENT, "file name required");
file = grub_file_open (args[0]);
if (! file)
return 0;
crc = 0;
while ((size = grub_file_read (file, buf, sizeof (buf))) > 0)
crc = grub_getcrc32 (crc, buf, size);
if (grub_errno)
goto fail;
grub_printf ("%08x\n", crc);
fail:
grub_file_close (file);
return 0;
}
static grub_command_t cmd;
GRUB_MOD_INIT(crc)
{
cmd = grub_register_command ("crc", grub_cmd_crc,
N_("FILE"),
N_("Calculate the crc32 checksum of a file."));
}
GRUB_MOD_FINI(crc)
{
grub_unregister_command (cmd);
}