Re: Two noncritical bugs of pg_waldump

Kyotaro Horiguchi <horikyota.ntt@gmail.com>

From: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
To: andres@anarazel.de
Cc: pgsql-hackers@postgresql.org
Date: 2022-03-02T08:37:04Z
Lists: pgsql-hackers
At Fri, 25 Feb 2022 10:48:47 -0800, Andres Freund <andres@anarazel.de> wrote in 
> Hi,
> 
> On 2022-02-14 18:18:47 +0900, Kyotaro Horiguchi wrote:
> > > If I give an empty file to the tool it complains as the follows.
> > > 
> > > > pg_waldump: fatal: could not read file "hoge": No such file or directory
> > > 
> > > No, the file exists.  The cause is it reads uninitialized errno to
> > > detect errors from the system call.  read(2) is defined to set errno
> > > always when it returns -1 and doesn't otherwise. Thus it seems to me
> > > that it is better to check that the return value is less than zero
> > > than to clear errno before the call to read().
> > 
> > So I post a patch contains only the indisputable part.
> 
> Thanks for the report and fix. Pushed. This was surprisingly painful, all but
> one branch had conflicts...

Ah, I didn't expect that this is committed so quickly.  I should have
created patches for all versions.  Anyway thanks for committing this!

regards.

-- 
Kyotaro Horiguchi
NTT Open Source Software Center



Commits

  1. pg_waldump: Fix error message for WAL files smaller than XLOG_BLCKSZ.