[U-Boot] fatls returncode

[Wolfgang Denk]

Dear Mirza,

In message <CAJ=nTstVijhpwMh9HfCbnzBzRz4GA9aujq=4oSWAkYCUs1+pOA at mail.gmail.com> you wrote:
> 
> > Please update to a recent versionof the code.  The return code
> > handling has probably been fixed by this commit:
> >
> > 0a04ed8   2015-09-11 17:15:21 -0400   FIX: fat: Provide correct return co=
> de from disk_{read|write} to upper layers
> 
> I did an update (cherry-picked FAT related commits from upstream), but
> I still get the same result.

I see.

> Analyzing the code in fs/fat/fat.c:do_fat_read_at (which is called by
> the fatls command) one can see that "ret" is set in three locations.
> In my case I never reach any of these three, since my exit path is:
> 
> fs/fat/fat.c:
> 
> 1139                 /* If end of rootdir reached */
> 1140                 if (rootdir_end) {
> 1141                         if (dols == LS_ROOT) {
> 1142                                 printf("\n%d file(s), %d dir(s)\n\n",
> 1143                                        files, dirs);
> 1144                                 *size = 0;
> 1145                         }
> 1146                         goto exit;
> 1147                 }

OK... Understood.

> So either this exit path is actually an error and it is correct as-is,
> or this path should set "ret = 0". My knowledge of FAT is limited so I
> can not really tell which it should be but there is no indications in
> the code/comments that this exit path is an error.

I think the exit is OK, as we have reached the end of the root
directory, but it should set "ret = 0;" before the goto.

But then, I am not an expert on this code either, so I added Sergei
Shtylyov on cc: who added this line with

commit ac4977719e157bcb3c45c70d9dd781164727530d
Author: Sergei Shtylyov <sshtylyov at ru.mvista.com>
Date:   Mon Aug 8 09:38:33 2011 +0000

    fat: fix crash with big sector size


Sergei, do you agree that ret = 0 should be set before the "goto
exit" here?

Best regards,

Wolfgang Denk

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