Re: Using XLogFileNameP in critical section

On Mon, 2 Dec 2019 at 16:56, Alvaro Herrera <alvherre@2ndquadrant.com> wrote:
>
> On 2019-Dec-02, Michael Paquier wrote:
>
> > I think that we had better just get rid of XLogFileNameP() (on HEAD)
> > and just change those code paths so as they use a buffer of size
> > MAXFNAMELEN, with XLogFileName() generating the file name.  This leads
> > actually to some simplifications, see for example XLogWalRcvWrite..
>
> +1, that function is a footgun and there's no possible way to fix it so
> that it's never misused(*).  Also, put a comment atop XLogFileName
> indicating never to create such a "helper" function again.
>
> (*) unless there was a way to have a StaticAssert() that the function is
> not called in a critical section -- have the compiler work for us.  I
> don't think it's possible to write such a thing.

Agreed. I've attached the updated version patch. Please review it.

Regards,

-- 
Masahiko Sawada            http://www.2ndQuadrant.com/
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