Re: Re: [COMMITTERS] pgsql: Map basebackup tablespaces using a tablespace_map file

On Fri, Jun 5, 2015 at 9:57 AM, Andrew Dunstan <andrew(at)dunslane(dot)net> wrote:

>
> On 06/04/2015 11:35 PM, Amit Kapila wrote:
>
>>
>> Theoretically, I don't see much problem by changing the checks
>> way you have done in patch, but it becomes different than what
>> we have in destroy_tablespace_directories() and it is slightly
>> changing the way check was originally done in
>> create_tablespace_directories(), basically original check will try
>> unlink if lstat returns non-zero return code. If you want to proceed
>> with the changed checks as in v3, then may be we can modify
>> comments on top of function remove_tablespace_symlink() which
>> indicates that it works like destroy_tablespace_directories().
>>
>>
>
> The difference is that here we're getting the list from a base backup and
> it seems to me the risk of having a file we don't really want to unlink is
> significantly greater.
>

Okay, I think I can understand why you want to be cautious for
having a different check for this path, but in that case there is a
chance that recovery might fail when it will try to create a symlink
for that file. Shouldn't we then try to call this new function only
when we are trying to restore from tablespace_map file and also
is there a need of ifdef S_ISLINK in remove_tablespace_link?

With Regards,
Amit Kapila.
EnterpriseDB: http://www.enterprisedb.com