mirror of
https://github.com/smaeul/u-boot.git
synced 2025-10-31 03:58:17 +00:00
54841ab50c
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>
105 lines
2.7 KiB
C
105 lines
2.7 KiB
C
/*
|
|
* (C) Copyright 2001
|
|
* Wolfgang Denk, DENX Software Engineering, wd@denx.de.
|
|
*
|
|
* 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
|
|
*/
|
|
|
|
/*
|
|
* Command to load a splash screen to the VFDs.
|
|
* NOTE that this will be controlled by a key combination when
|
|
* the keyboard stuff works. For now the user has to enter a
|
|
* bitmap number (only VFD_TEST_LOGO is supported now - 16.10.2002).
|
|
* Added VFD_REMOTE_LOGO (same as VFD_TEST_LOGO but a different color)
|
|
* on 20.10.2002.
|
|
*
|
|
* This rather crudely requires that each bitmap be included as a
|
|
* header file.
|
|
*/
|
|
#include <common.h>
|
|
#include <command.h>
|
|
|
|
#if defined(CONFIG_CMD_VFD)
|
|
|
|
#include <vfd_logo.h>
|
|
#define VFD_TEST_LOGO_BMPNR 0
|
|
#define VFD_REMOTE_LOGO_BMPNR 1
|
|
|
|
extern int transfer_pic(unsigned char, unsigned char *, int, int);
|
|
|
|
int trab_vfd (ulong bitmap);
|
|
|
|
int do_vfd (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
|
|
{
|
|
ulong bitmap;
|
|
|
|
if (argc != 2) {
|
|
cmd_usage(cmdtp);
|
|
return 1;
|
|
}
|
|
|
|
if (argv[1][0] == '/') { /* select bitmap by number */
|
|
bitmap = simple_strtoul(argv[1]+1, NULL, 10);
|
|
return (trab_vfd(bitmap));
|
|
}
|
|
|
|
/* display bitmap at given address */
|
|
bitmap = simple_strtoul(argv[1], NULL, 16);
|
|
transfer_pic(3, (uchar *)bitmap, VFD_LOGO_HEIGHT, VFD_LOGO_WIDTH);
|
|
return 0;
|
|
}
|
|
|
|
U_BOOT_CMD(
|
|
vfd, 2, 0, do_vfd,
|
|
"load a bitmap to the VFDs on TRAB",
|
|
"/N\n"
|
|
" - load bitmap N to the VFDs (N is _decimal_ !!!)\n"
|
|
"vfd ADDR\n"
|
|
" - load bitmap at address ADDR"
|
|
);
|
|
#endif
|
|
|
|
int trab_vfd (ulong bitmap)
|
|
{
|
|
uchar *addr;
|
|
char *s;
|
|
|
|
switch (bitmap) {
|
|
case VFD_TEST_LOGO_BMPNR:
|
|
if ((s = getenv ("bitmap0")) != NULL) {
|
|
addr = (uchar *)simple_strtoul (s, NULL, 16);
|
|
} else {
|
|
addr = &vfd_test_logo_bitmap[0];
|
|
}
|
|
break;
|
|
case VFD_REMOTE_LOGO_BMPNR:
|
|
if ((s = getenv ("bitmap1")) != NULL) {
|
|
addr = (uchar *)simple_strtoul (s, NULL, 16);
|
|
} else {
|
|
addr = &vfd_remote_logo_bitmap[0];
|
|
}
|
|
break;
|
|
default:
|
|
printf("Unknown bitmap %ld\n", bitmap);
|
|
return 1;
|
|
}
|
|
transfer_pic(3, addr, VFD_LOGO_HEIGHT, VFD_LOGO_WIDTH);
|
|
return 0;
|
|
}
|