From mboxrd@z Thu Jan  1 00:00:00 1970
From: Pavel Herrmann <morpheus.ibis@gmail.com>
Date: Wed, 05 Sep 2012 22:25:29 +0200
Subject: [U-Boot] [PATCH v3 1/2] Loop block device for sandbox
In-Reply-To: <201209051448.40473.marex@denx.de>
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	<6135983.HUgUjpG9li@merom> <201209051448.40473.marex@denx.de>
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On Wednesday 05 of September 2012 14:48:40 Marek Vasut wrote:
> Dear Pavel Herrmann,
> 
> [...]
> 
> > > besides, I think it'd be much systematic to just scream at user to call
> > > "sata rescan" and bail out instead of doing it for him.
> > 
> > i dont actually need a sata rescan, i just need to make sure i have
> > dynamically allocated names
> 
> Sorry, I can't parse this ... but ...
> 
> > , so i can safely call free() later, otherwise
> > this segfaults when called before sata scan
> 
> The free() function frees the memory space pointed to by ptr, which must
> have been returned by a previous call to malloc(), calloc() or realloc(). 
> Otherwise, or if free(ptr) has already been called before, undefined 
> behavior  occurs. If ptr is NULL, no operation is performed.
> 
> So if you call free() on null pointer, nothing happens. Where's the real
> problem?

if you called "sata init" before setting all the loops you would get to 
open(NULL) and a strlen(NULL). i think its easier to supply valid empty string 
then check for NULL at every access.

> > > 
> > > Make this "info" part mandatory. Than you can cut the whole argc loop
> > > into simple "if argc != 2 ; then fail" . And do simple checking for the
> > > first letter of the argument being either i or d .
> > 
> > wont help, still need argc 3 or 4
> 
> Makes is simpler, you can bail out if it's not 3 or 4

still, i should have a "sata_loop info" work on all files, so theres a valid 
command with argc 2

> > > > +	"sata_loop load devnum file - load file from host FS into loop
> > > > devnum"
> > > 
> > > sata_loop is redundant above.
> > 
> > really? how do you figure?
> 
> Run "help sata_loop" and see the result ...

=>help sata_loop
sata_loop - SATA loopback

Usage:
sata_loop [info] devnum - show info about loop devnum
sata_loop load devnum file - load file from host FS into loop devnum

i dont see your problem

Pavel Herrmann