[Gluster-devel] glusterfs_open() glusterfs_fstat() glusterfs_readdir() bug?

[Shehjar Tikoo]

Serial Thrilla wrote:
> I was doing some investigation into the glusterfs_readdir() issue:
> 
> On my system, dirent struct member "d_reclen" is an "unsigned short int"
> but the _gf_dirent_t dirent struct "d_len" member is a uint32_t
> (unsigned long int).

That seems to be an indicator of a problem because the second
glfs.c test works fine on an empty directory on my system.

I'll be looking into this next week.

Thanks
-Shehjar

> 
> libglusterfsclient.c line 2438 has:
> 
> dirp->d_reclen = entry->d_len;
> 
> It looks to me like that value is too big and possibly not storing the
> correct record length. May also explain why the line before:
> 
> /* dirp->d_type = entry->d_type; */
> 
> is commented out because it was being overwritten by the d_reclen
> assignment.
> 
> Since this value is being stored incorrectly, line 2440 then uses the
> reclen from dirent for the null byte. Might explain why I get a huge
> reclen and only get one random character as the entry name.
> 
> Attached is my system's dirent struct.
> 
> Thanks!
> Rob
> 
> 
> Serial Thrilla wrote:
>> Thanks! That patch fixes the glusterfs_fstat() call.
>> Unfortunately, glusterfs_readdir() wasn't fixed.
>>
>> Attached is the new code, output, and logs. At the moment there are no
>> entries in /home/export/ so I'm not sure why it is returning "f" and
>> then another return with no name.
>>
>> I had an issue before with 3 entries in /home/export (test, test2,
>> test3). It was returning 4 items from glusterfs_readdir() and they were
>> all one letter names like "P", "[".
>>
>> The "count" parameter for glusterfs_readdir() doesn't appear to be used
>> so I made it 0 for now. Changing it to other values has no effect.
>>
>>
>> Thanks
>> Rob
>>
>>
>> Shehjar Tikoo wrote:
>>> Hi
>>>
>>> Thanks for the report. The attached patch should fix this problem
>>> for rc7. The test program, glfs.c, works fine for me with this
>>> patch applied while using the volfiles supplied. Could you please
>>> confirm if this works for your setup?
>>>
>>> Thanks
>>> Shehjar
>>>
>>> Serial Thrilla wrote:
>>>> Hey all, attached are the code and output of server and client.
>>>>
>>>> *Please be aware that the server and client run on the same machine*
>>>>
>>>> glusterfs_open() will return a file descriptor but glusterfs_fstat()
>>>>  returns -1 for that descriptor.
>>>>
>>>> Is it normal for the file descriptor to change on each call to
>>>> glusterfs_open() despite the same parameters?
>>>>
>>>> Also, I was having issues with glusterfs_readdir() but that wasn't
>>>> working either so I suspect there's an issue with the descriptor.
>>>>
>>>> Please let me know if you need any more info.
>>>>
>>>> Attn core developers: Please let me know if you would like access to
>>>> my dev box and I'll be happy to provide it.
>>>>
>>>> Thanks Rob