Horton

Re: libpq debug log

Kyotaro Horiguchi <horikyota.ntt@gmail.com>

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From: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
To: tsunakawa.takay@fujitsu.com
Cc: alvherre@alvh.no-ip.org, iwata.aya@fujitsu.com, tgl@sss.pgh.pa.us, k.jamison@fujitsu.com, pgsql-hackers@lists.postgresql.org
Date: 2021-03-11T03:11:19Z
Lists: pgsql-hackers 
At Thu, 11 Mar 2021 03:01:16 +0000, "tsunakawa.takay@fujitsu.com" <tsunakawa.takay@fujitsu.com> wrote in 
> From: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
> > The output functions copy message bytes into local variable but the
> > same effect can be obtained by just casing via typed pointer type.
> > 
> >   uint32 tmp4;
> >   ..
> >   memcpy(&tmp4, buf + *cursor, 4);
> >   result = (int) pg_ntoh32(tmp4);
> > 
> > can be written as
> > 
> >   result = pg_ntoh32(* (uint32 *) (buf + *cursor));
> 
> I'm afraid we need to memcpy() because of memory alignment.

Right. So something like this?

unsigned char p;

p = buf + *cursor;
result = (uint32) (*p << 24) + (*(p + 1)) << 16 + ...);


> > I think we can get rid of copying in the output functions for String
> > and Bytes in different ways.
> 
> I haven't looked at this code, but you sound right.

regards.

-- 
Kyotaro Horiguchi
NTT Open Source Software Center

Commits

  1. Rename PQtraceSetFlags() to PQsetTraceFlags().

  2. Suppress length of Notice/Error msgs in PQtrace regress mode

  3. Strip file names reported in error messages on Windows, too.

  4. Fix setvbuf()-induced crash in libpq_pipeline

  5. libpq_pipeline: Must strdup(optarg) to avoid crash

  6. Remove setvbuf() call from PQtrace()

  7. Initialize conn->Pfdebug to NULL when creating a connection

  8. Disable force_parallel_mode in libpq_pipeline

  9. libpq_pipeline: add PQtrace() support and tests

  10. Improve PQtrace() output format

  11. Re-simplify management of inStart in pqParseInput3's subroutines.