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>
A small number of common/cmd_*.c files contain preprocessor tests that
are apparently superfluous since those same tests are used in the
Makefile to control the compilation of those files. Those tests are
clearly redundant as long as they surround the entirety of the source
in those files.
Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Many of the help messages were not really helpful; for example, many
commands that take no arguments would not print a correct synopsis
line, but "No additional help available." which is not exactly wrong,
but not helpful either.
Commit ``Make "usage" messages more helpful.'' changed this
partially. But it also became clear that lots of "Usage" and "Help"
messages (fields "usage" and "help" in struct cmd_tbl_s respective)
were actually redundant.
This patch cleans this up - for example:
Before:
=> help dtt
dtt - Digital Thermometer and Thermostat
Usage:
dtt - Read temperature from digital thermometer and thermostat.
After:
=> help dtt
dtt - Read temperature from Digital Thermometer and Thermostat
Usage:
dtt
Signed-off-by: Wolfgang Denk <wd@denx.de>
Mflash is fusion memory device mainly targeted consumer eletronic and
mobile phone.
Internally, it have nand flash and other hardware logics and supports
some different operation (ATA, IO, XIP) modes.
IO mode is custom mode for the host that doesn't have IDE interface.
(Many mobile targeted SoC doesn't have IDE bus)
This driver support mflash IO mode.
Followings are brief descriptions about IO mode.
1. IO mode based on ATA protocol and uses some custom command. (read
confirm, write confirm)
2. IO mode uses SRAM bus interface.
Signed-off-by: unsik Kim <donari75@gmail.com>
Wolfgang Denk
Robert P. J. Day
unsik Kim