[CLOSED] SEGGER_RTT_vprintf / SEGGER_RTT_printf string format NULL check

Hi Segger Team,

we're having software that passes printf format strings with %s in the format string, but the corresponding char * is NULL in same cases.

As it is cumbersome to check the variadic arguments (va_args) values before passing them into SEGGER_RTT_vprintf we do patch the Segger RTT sources with an additional check right now.

We also created a patch file: null_string_va_arg.zip

It would be nice, if this patch could get part of the official RTT release.

Thanks

Best regards
Philipp Häfele

Hi mwb1100,

wasn't aware of that behavior.

Patch would then look something like that:

if(s == NULL) {
                _StoreChar(&BufferDesc, '(');
                _StoreChar(&BufferDesc, 'n');
                _StoreChar(&BufferDesc, 'u');
                _StoreChar(&BufferDesc, 'l');
                _StoreChar(&BufferDesc, 'l');
                _StoreChar(&BufferDesc, ')');
                break;
            }

which is also totally ok

Hi,

there was an error in my code block i posted above, which i fixed there.

I now also created a patch file, including the "(null)" printing.

@SEGGER - Nino Any minds about this patch?

Best regards
Philipp

Hi again,

i just found a much simpler and less error prone patch and also added a "NULL" fallback definition that i got from the SEGGER_RTT.c

null_string_va_arg_with_null_print_simplyfied.zip

Best regards
Philipp