grub/commands/memrw.c

102 lines
3.0 KiB
C

/* memrw.c - command to read / write physical memory */
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2009 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/misc.h>
#include <grub/command.h>
static grub_command_t cmd_read_byte, cmd_read_word, cmd_read_dword;
static grub_command_t cmd_write_byte, cmd_write_word, cmd_write_dword;
static grub_err_t
grub_cmd_read (grub_command_t cmd, int argc, char **argv)
{
grub_target_addr_t addr;
grub_uint32_t value;
if (argc != 1)
return grub_error (GRUB_ERR_BAD_ARGUMENT, "Invalid number of arguments");
addr = grub_strtoul (argv[0], 0, 0);
if (cmd->name[5] == 'd')
value = *((grub_uint32_t *) addr);
else if (cmd->name[5] == 'w')
value = *((grub_uint16_t *) addr);
else
value = *((grub_uint8_t *) addr);
grub_printf ("0x%x\n", value);
return 0;
}
static grub_err_t
grub_cmd_write (grub_command_t cmd, int argc, char **argv)
{
grub_target_addr_t addr;
grub_uint32_t value;
if (argc != 2)
return grub_error (GRUB_ERR_BAD_ARGUMENT, "Invalid number of arguments");
addr = grub_strtoul (argv[0], 0, 0);
value = grub_strtoul (argv[1], 0, 0);
if (cmd->name[6] == 'd')
*((grub_uint32_t *) addr) = value;
else if (cmd->name[6] == 'w')
*((grub_uint16_t *) addr) = (grub_uint16_t) value;
else
*((grub_uint8_t *) addr) = (grub_uint8_t) value;
return 0;
}
GRUB_MOD_INIT(memrw)
{
(void) mod; /* To stop warning. */
cmd_read_byte =
grub_register_command ("read_byte", grub_cmd_read,
"read_byte ADDR", "read byte.");
cmd_read_word =
grub_register_command ("read_word", grub_cmd_read,
"read_word ADDR", "read word.");
cmd_read_dword =
grub_register_command ("read_dword", grub_cmd_read,
"read_dword ADDR", "read dword.");
cmd_write_byte =
grub_register_command ("write_byte", grub_cmd_write,
"write_byte ADDR VALUE", "write byte.");
cmd_write_word =
grub_register_command ("write_word", grub_cmd_write,
"write_word ADDR VALUE", "write word.");
cmd_write_dword =
grub_register_command ("write_dword", grub_cmd_write,
"write_dword ADDR VALUE", "write dword.");
}
GRUB_MOD_FINI(memrw)
{
grub_unregister_command (cmd_read_byte);
grub_unregister_command (cmd_read_word);
grub_unregister_command (cmd_read_dword);
grub_unregister_command (cmd_write_byte);
grub_unregister_command (cmd_write_word);
grub_unregister_command (cmd_write_dword);
}