[PATCH] modutils: Add /proc/cmdline module option parsing support

[Ozan Çağlayan]

Stefan Seyfried wrote:
> On Sat, 23 Jan 2010 01:50:20 +0200
> Ozan Çağlayan <ozan at pardus.org.tr> wrote:
> 
>> This adds module option parsing support from /proc/cmdline like in
>> module-init-tools.
>>
>> The options passed through /proc/cmdline are always squeezed by the ones
>> provided with command line arguments.
> 
> Can you tell us something about the code size increase? Rule of thumb:
> if it's more than 10 bytes and an obscure feature (from an embedded
> POV), then it should be wrapped in CONFIG_FEATURE_.... ;-)

function                                             old     new   delta
parse_kcmdline_module_options                          -     218    +218
do_modprobe                                          356     376     +20
.rodata                                           126228  126243     +15
gather_options_str                                    75      79      +4
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 3/0 up/down: 257/0)             Total: 257 bytes
   text    data     bss     dec     hex filename
 674967    2057    9040  686064   a77f0 busybox_old
 675224    2057    9040  686321   a78f1 busybox_unstripped

So it's far from +10 :)

BTW, the +4 in gather_options_str is a general fix which avoids possible NULL pointer dereferences
so it's +253 :)

If you think that it's not necessary at all to provide this functionality, I'll keep this patch local to my busybox
or else I'll spin another patch with FEATURE_ stuff.

Thanks!