Horton

Re: libpq debug log

Kyotaro Horiguchi <horikyota.ntt@gmail.com>

View thread View on postgr.es
From: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
To: tsunakawa.takay@fujitsu.com
Cc: iwata.aya@fujitsu.com, alvherre@alvh.no-ip.org, tgl@sss.pgh.pa.us, k.jamison@fujitsu.com, pgsql-hackers@lists.postgresql.org
Date: 2021-03-18T08:30:05Z
Lists: pgsql-hackers 
At Thu, 18 Mar 2021 07:34:36 +0000, "tsunakawa.takay@fujitsu.com" <tsunakawa.takay@fujitsu.com> wrote in 
> From: Iwata, Aya/岩田 彩 <iwata.aya@fujitsu.com>
> > > Yes, precisely, 2 bytes for the double quotes needs to be subtracted
> > > as
> > > follows:
> > >
> > > 	len = fprintf(...);
> > > 	*cursor += (len - 2);
> > 
> > Thank you for your advice. I changed pqTraceOutputString set cursor to fprintf
> > return -2.
> > And I removed cursor movement from that function.
> 
> Ouch, not 2 but 3, to include a single whitespace at the beginning.
> 
> The rest looks good.  I hope we're almost at the finish line.

Maybe.

At Wed, 17 Mar 2021 13:36:32 -0300, Alvaro Herrera <alvherre@alvh.no-ip.org> wrote in 
> In pqTraceOutputString(), you can use the return value from fprintf to
> move the cursor -- no need to count chars.
> 
> I still think that the message-type specific functions should print the
> message type, rather than having the string arrays.

In other words, pqTraceOutputMessage recognizes message id and calls
the function corresponding one-on-one to the id. So the functions
knows what is the message type of myself and there's no reason for
pqTraceOutputMessage to print the message type on its behalf.


+ pqTraceOutputR(const char *message, FILE *f)
+ {
+ 	int	cursor = 0;
+ 
+ 	pqTraceOutputInt32(message, &cursor, f);

I don't understand the reason for spliting message and &cursor here.

+ pqTraceOutputR(const char *message, FILE *f)
+ {
+ 	char *p = message;
+ 
+ 	pqTraceOutputInt32(&p, f);

works well.


+/* RowDescription */
+static void
+pqTraceOutputT(const char *message, int end, FILE *f)
+{
+	int	cursor = 0;
+	int nfields;
+	int	i;
+
+	nfields = pqTraceOutputInt16(message, &cursor, f);
+
+	for (i = 0; i < nfields; i++)
+	{
+		pqTraceOutputString(message, &cursor, end, f);
+		pqTraceOutputInt32(message, &cursor, f);
+		pqTraceOutputInt16(message, &cursor, f);
+		pqTraceOutputInt32(message, &cursor, f);
+		pqTraceOutputInt16(message, &cursor, f);
+		pqTraceOutputInt32(message, &cursor, f);
+		pqTraceOutputInt16(message, &cursor, f);
+	}
+}

I didn't looked closer, but lookong the usage of the variable "end",
something's wrong in the function.

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.