Re: Using XLogFileNameP in critical section

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.

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
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