u-boot/board/digsy_mtc/cmd_mtc.c
Wolfgang Denk 54841ab50c Make sure that argv[] argument pointers are not modified.
The hush shell dynamically allocates (and re-allocates) memory for the
argument strings in the "char *argv[]" argument vector passed to
commands.  Any code that modifies these pointers will cause serious
corruption of the malloc data structures and crash U-Boot, so make
sure the compiler can check that no such modifications are being done
by changing the code into "char * const argv[]".

This modification is the result of debugging a strange crash caused
after adding a new command, which used the following argument
processing code which has been working perfectly fine in all Unix
systems since version 6 - but not so in U-Boot:

int main (int argc, char **argv)
{
	while (--argc > 0 && **++argv == '-') {
/* ====> */	while (*++*argv) {
			switch (**argv) {
			case 'd':
				debug++;
				break;
			...
			default:
				usage ();
			}
		}
	}
	...
}

The line marked "====>" will corrupt the malloc data structures and
usually cause U-Boot to crash when the next command gets executed by
the shell.  With the modification, the compiler will prevent this with
an
	error: increment of read-only location '*argv'

N.B.: The code above can be trivially rewritten like this:

	while (--argc > 0 && **++argv == '-') {
		char *arg = *argv;
		while (*++arg) {
			switch (*arg) {
			...

Signed-off-by: Wolfgang Denk <wd@denx.de>
Acked-by: Mike Frysinger <vapier@gentoo.org>
2010-07-04 23:55:42 +02:00

358 lines
8.1 KiB
C

/*
* (C) Copyright 2009
* Werner Pfister <Pfister_Werner@intercontrol.de>
*
* (C) Copyright 2009 Semihalf, Grzegorz Bernacki
*
* See file CREDITS for list of people who contributed to this
* project.
*
* 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 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, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*/
#include <common.h>
#include <command.h>
#include <mpc5xxx.h>
#include "spi.h"
#include "cmd_mtc.h"
DECLARE_GLOBAL_DATA_PTR;
static const char *led_names[] = {
"diag",
"can1",
"can2",
"can3",
"can4",
"usbpwr",
"usbbusy",
"user1",
"user2",
""
};
static int msp430_xfer(const void *dout, void *din)
{
int err;
err = spi_xfer(NULL, MTC_TRANSFER_SIZE, dout, din,
SPI_XFER_BEGIN | SPI_XFER_END);
/* The MSP chip needs time to ready itself for the next command */
udelay(1000);
return err;
}
static void mtc_calculate_checksum(tx_msp_cmd *packet)
{
int i;
uchar *buff;
buff = (uchar *) packet;
for (i = 0; i < 6; i++)
packet->cks += buff[i];
}
static int do_mtc_led(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
tx_msp_cmd pcmd;
rx_msp_cmd prx;
int err;
int i;
if (argc < 2) {
cmd_usage(cmdtp);
return -1;
}
memset(&pcmd, 0, sizeof(pcmd));
memset(&prx, 0, sizeof(prx));
pcmd.cmd = CMD_SET_LED;
pcmd.cmd_val0 = 0xff;
for (i = 0; strlen(led_names[i]) != 0; i++) {
if (strncmp(argv[1], led_names[i], strlen(led_names[i])) == 0) {
pcmd.cmd_val0 = i;
break;
}
}
if (pcmd.cmd_val0 == 0xff) {
printf("Usage:\n%s\n", cmdtp->help);
return -1;
}
if (argc >= 3) {
if (strncmp(argv[2], "red", 3) == 0)
pcmd.cmd_val1 = 1;
else if (strncmp(argv[2], "green", 5) == 0)
pcmd.cmd_val1 = 2;
else if (strncmp(argv[2], "orange", 6) == 0)
pcmd.cmd_val1 = 3;
else
pcmd.cmd_val1 = 0;
}
if (argc >= 4)
pcmd.cmd_val2 = simple_strtol(argv[3], NULL, 10);
else
pcmd.cmd_val2 = 0;
mtc_calculate_checksum(&pcmd);
err = msp430_xfer(&pcmd, &prx);
return err;
}
static int do_mtc_key(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
tx_msp_cmd pcmd;
rx_msp_cmd prx;
int err;
memset(&pcmd, 0, sizeof(pcmd));
memset(&prx, 0, sizeof(prx));
pcmd.cmd = CMD_GET_VIM;
mtc_calculate_checksum(&pcmd);
err = msp430_xfer(&pcmd, &prx);
if (!err) {
/* function returns '0' if key is pressed */
err = (prx.input & 0x80) ? 0 : 1;
}
return err;
}
static int do_mtc_digout(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
tx_msp_cmd pcmd;
rx_msp_cmd prx;
int err;
uchar channel_mask = 0;
if (argc < 3) {
cmd_usage(cmdtp);
return -1;
}
if (strncmp(argv[1], "on", 2) == 0)
channel_mask |= 1;
if (strncmp(argv[2], "on", 2) == 0)
channel_mask |= 2;
memset(&pcmd, 0, sizeof(pcmd));
memset(&prx, 0, sizeof(prx));
pcmd.cmd = CMD_GET_VIM;
pcmd.user_out = channel_mask;
mtc_calculate_checksum(&pcmd);
err = msp430_xfer(&pcmd, &prx);
return err;
}
static int do_mtc_digin(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
tx_msp_cmd pcmd;
rx_msp_cmd prx;
int err;
uchar channel_num = 0;
if (argc < 2) {
cmd_usage(cmdtp);
return -1;
}
channel_num = simple_strtol(argv[1], NULL, 10);
if ((channel_num != 1) && (channel_num != 2)) {
printf("mtc digin: invalid parameter - must be '1' or '2'\n");
return -1;
}
memset(&pcmd, 0, sizeof(pcmd));
memset(&prx, 0, sizeof(prx));
pcmd.cmd = CMD_GET_VIM;
mtc_calculate_checksum(&pcmd);
err = msp430_xfer(&pcmd, &prx);
if (!err) {
/* function returns '0' when digin is on */
err = (prx.input & channel_num) ? 0 : 1;
}
return err;
}
static int do_mtc_appreg(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
tx_msp_cmd pcmd;
rx_msp_cmd prx;
int err;
char buf[5];
/* read appreg */
memset(&pcmd, 0, sizeof(pcmd));
memset(&prx, 0, sizeof(prx));
pcmd.cmd = CMD_WD_PARA;
pcmd.cmd_val0 = 5; /* max. Count */
pcmd.cmd_val1 = 5; /* max. Time */
pcmd.cmd_val2 = 0; /* =0 means read appreg */
mtc_calculate_checksum(&pcmd);
err = msp430_xfer(&pcmd, &prx);
if (!err) {
sprintf(buf, "%d", prx.ack2);
setenv("appreg", buf);
}
return err;
}
static int do_mtc_version(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
tx_msp_cmd pcmd;
rx_msp_cmd prx;
int err;
memset(&pcmd, 0, sizeof(pcmd));
memset(&prx, 0, sizeof(prx));
pcmd.cmd = CMD_FW_VERSION;
mtc_calculate_checksum(&pcmd);
err = msp430_xfer(&pcmd, &prx);
if (!err) {
printf("FW V%d.%d.%d / HW %d\n",
prx.ack0, prx.ack1, prx.ack3, prx.ack2);
}
return err;
}
static int do_mtc_state(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
tx_msp_cmd pcmd;
rx_msp_cmd prx;
int err;
memset(&pcmd, 0, sizeof(pcmd));
memset(&prx, 0, sizeof(prx));
pcmd.cmd = CMD_WD_WDSTATE;
pcmd.cmd_val2 = 1;
mtc_calculate_checksum(&pcmd);
err = msp430_xfer(&pcmd, &prx);
if (!err) {
printf("State %02Xh\n", prx.state);
printf("Input %02Xh\n", prx.input);
printf("UserWD %02Xh\n", prx.ack2);
printf("Sys WD %02Xh\n", prx.ack3);
printf("WD Timout %02Xh\n", prx.ack0);
printf("eSysState %02Xh\n", prx.ack1);
}
return err;
}
static int do_mtc_help(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]);
cmd_tbl_t cmd_mtc_sub[] = {
U_BOOT_CMD_MKENT(led, 3, 1, do_mtc_led,
"set state of leds",
"[ledname] [state] [blink]\n"
" - lednames: diag can1 can2 can3 can4 usbpwr usbbusy user1 user2\n"
" - state: off red green orange\n"
" - blink: blink interval in 100ms steps (1 - 10; 0 = static)\n"),
U_BOOT_CMD_MKENT(key, 0, 1, do_mtc_key,
"returns state of user key", ""),
U_BOOT_CMD_MKENT(version, 0, 1, do_mtc_version,
"returns firmware version of supervisor uC", ""),
U_BOOT_CMD_MKENT(appreg, 0, 1, do_mtc_appreg,
"reads appreg value and stores in environment variable 'appreg'", ""),
U_BOOT_CMD_MKENT(digin, 1, 1, do_mtc_digin,
"returns state of digital input",
"<channel_num> - get state of digital input (1 or 2)\n"),
U_BOOT_CMD_MKENT(digout, 2, 1, do_mtc_digout,
"sets digital outputs",
"<on|off> <on|off>- set state of digital output 1 and 2\n"),
U_BOOT_CMD_MKENT(state, 0, 1, do_mtc_state,
"displays state", ""),
U_BOOT_CMD_MKENT(help, 4, 1, do_mtc_help, "get help",
"[command] - get help for command\n"),
};
static int do_mtc_help(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
extern int _do_help(cmd_tbl_t *cmd_start, int cmd_items,
cmd_tbl_t *cmdtp, int flag,
int argc, char * const argv[]);
#ifdef CONFIG_SYS_LONGHELP
puts("mtc ");
#endif
return _do_help(&cmd_mtc_sub[0],
ARRAY_SIZE(cmd_mtc_sub), cmdtp, flag, argc, argv);
}
int cmd_mtc(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
cmd_tbl_t *c;
int err = 0;
c = find_cmd_tbl(argv[1], &cmd_mtc_sub[0], ARRAY_SIZE(cmd_mtc_sub));
if (c) {
argc--;
argv++;
return c->cmd(c, flag, argc, argv);
} else {
/* Unrecognized command */
cmd_usage(cmdtp);
return 1;
}
return err;
}
U_BOOT_CMD(mtc, 5, 1, cmd_mtc,
"special commands for digsyMTC",
"[subcommand] [args...]\n"
"Subcommands list:\n"
"led [ledname] [state] [blink] - set state of leds\n"
" [ledname]: diag can1 can2 can3 can4 usbpwr usbbusy user1 user2\n"
" [state]: off red green orange\n"
" [blink]: blink interval in 100ms steps (1 - 10; 0 = static)\n"
"key - returns state of user key\n"
"version - returns firmware version of supervisor uC\n"
"appreg - reads appreg value and stores in environment variable"
" 'appreg'\n"
"digin [channel] - returns state of digital input (1 or 2)\n"
"digout <on|off> <on|off> - sets state of two digital outputs\n"
"state - displays state\n"
"help [subcommand] - get help for subcommand\n"
);