Horton

RE: libpq debug log

tsunakawa.takay@fujitsu.com <tsunakawa.takay@fujitsu.com>

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From: "tsunakawa.takay@fujitsu.com" <tsunakawa.takay@fujitsu.com>
To: 'Alvaro Herrera' <alvherre@alvh.no-ip.org>, "iwata.aya@fujitsu.com" <iwata.aya@fujitsu.com>
Cc: 'Tom Lane' <tgl@sss.pgh.pa.us>, 'Kyotaro Horiguchi' <horikyota.ntt@gmail.com>, "k.jamison@fujitsu.com" <k.jamison@fujitsu.com>, "pgsql-hackers@lists.postgresql.org" <pgsql-hackers@lists.postgresql.org>
Date: 2021-03-18T03:38:09Z
Lists: pgsql-hackers 
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
> In pqTraceOutputString(), you can use the return value from fprintf to
> move the cursor -- no need to count chars.

Yes, precisely, 2 bytes for the double quotes needs to be subtracted as follows:

	len = fprintf(...);
	*cursor += (len - 2);


> I still think that the message-type specific functions should print the
> message type, rather than having the string arrays.

I sort of think so to remove the big arrays.  But to minimize duplicate code, I think the code structure will look like:

	fprintf(timestamp, length);
	switch (type)
	{
		case '?':
			pqTraceOutput?(...);
		break;
		case '?':
			/* No message content */
			fprintf("message_type_name");
		break;
	}	

void
pqTraceOutput?(...)
{
	fprintf("message_type_name");
	print message content;	
}

The order of length and message type is reversed.  The .sgml should also be changed accordingly.  What do you think?

Iwata-san, 
Why don't you submit v27 patch with the current arrays kept, and then v28 with the arrays removed soon after?


From: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
> It would help when the value is "255", which is confusing between -1
> (or 255) in byte or 255 in 2-byte word. Or when the value looks like
> broken. I'd suggest "b"yte for 1 byte, "s"hort for 2 bytes, "l"ong for
> 4 bytes ('l' is confusing with '1', but anyway it is not needed)..

I don't have a strong opinion on this.  (I kind of think I want to see unprefixed numbers; readers will look at the protocol reference anyway.)  I'd like to leave this up to Iwata-san and Alvaro-san.


	Regards
Takayuki Tsunakawa}

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.