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* Make sure that argv[] argument pointers are not modified.Wolfgang Denk2010-07-04-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* Prepare v2010.06-rc3v2010.06-rc3Wolfgang Denk2010-06-23-1/+1
| | | | Signed-off-by: Wolfgang Denk <wd@denx.de>
* cmd_setexpr: allow memory addresses in expressionsFrans Meulenbroeks2010-03-21-4/+30
| | | | | | | | | | | | | | | | This patch add functionality to use memory addresses in expressions. This increases the power of expressions substantially It adheres to the standard convemtions: memory addresses can be given in the format *address (e.g. *1000) Rationale for this change is that it allows masking off bits from a byte that is obtained by reading data from e.g. i2c. Signed-off-by: Frans Meulenbroeks <fransmeulenbroeks@gmail.com> Fix warning: control reaches end of non-void function Signed-off-by: Wolfgang Denk <wd@denx.de>
* General help message cleanupWolfgang Denk2009-06-12-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* Command usage cleanupPeter Tyser2009-01-28-1/+1
| | | | | | | | Remove command name from all command "usage" fields and update common/command.c to display "name - usage" instead of just "usage". Also remove newlines from command usage fields. Signed-off-by: Peter Tyser <ptyser@xes-inc.com>
* Standardize command usage messages with cmd_usage()Peter Tyser2009-01-28-1/+1
| | | | Signed-off-by: Peter Tyser <ptyser@xes-inc.com>
* Add setexpr commandKumar Gala2008-03-25-0/+70
Add a simple expr style command that will set an env variable as the result of the command. This allows us to do simple math in shell. The following operations are supported: &, |, ^, +, -, *, /. Signed-off-by: Kumar Gala <galak@kernel.crashing.org>