[U-Boot] fatls returncode

[Mirza Krak]

2017-03-27 10:51 GMT+02:00 Wolfgang Denk <wd at denx.de>:
> 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?

I also found the commit that removed the "ret = 0" since it did indeed
exist earlier.

    1ad0b98a067a ("fat: Prepare API change for files greater than 2GB")

Added author on CC.

That commit also removed another occurrence of "ret = 0" which I
question if that was correct as well.

-- 
Med Vänliga Hälsningar / Best Regards

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Mirza Krak
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