anymore.  Fix for large objects.

Date: Sun, 16 Aug 1998 14:56:48 -0400
From: Tom Lane <tgl@sss.pgh.pa.us>
Attached is a patch for this weekend's work on libpq.  I've dealt
with several issues:

        <for details: see message, in pgsql-patches archive for above data>

The attached patch implements some changes that were discussed a
couple weeks ago on the hackers and interfaces lists:

1. When the backend sends a NOTICE message and closes the connection
   (typically, because it was told to by the postmaster after
   another backend coredumped), libpq will now print the notice
   and close the connection cleanly.  Formerly, the frontend app
   would usually terminate ungracefully due to a SIGPIPE.  (I am
   not sure if 6.3.2 behaved that way, but the current cvs sources
   do...)

2. libpq's various printouts to stderr are now fed through a single
   "notice processor" routine, which can be overridden by the
   application to direct notices someplace else.  This should ease
   porting libpq to Windows.

I also noticed and fixed a problem in PQprint: when sending output
to a pager subprocess, it would disable SIGPIPE in case the pager
terminates early (this is good) --- but afterwards it reset SIGPIPE
to SIG_DFL, rather than restoring the application's prior setting
(bad).

			regards, tom lane

From: Tom Lane <tgl@sss.pgh.pa.us>

Making PQrequestCancel safe to call in a signal handler turned out to be
much easier than I feared.  So here are the diffs.

Some notes:
  * I modified the postmaster's packet "iodone" callback interface to allow
    the callback routine to return a continue-or-drop-connection return
    code; this was necessary to allow the connection to be closed after
    receiving a Cancel, rather than proceeding to launch a new backend...
    Being a neatnik, I also made the iodone proc have a typechecked
    parameter list.
  * I deleted all code I could find that had to do with OOB.
  * I made some edits to ensure that all signals mentioned in the code
    are referred to symbolically not by numbers ("SIGUSR2" not "2").
    I think Bruce may have already done at least some of the same edits;
    I hope that merging these patches is not too painful.

Through some minor changes, I have been able to compile the libpq
client libraries on the Win32 platform. Since the libpq communications
part has been rewritten, this has become much easier. Enclosed is
a patch that will allow at least Microsoft Visual C++ to compile
libpq into both a static and a dynamic library.  I will take a look
at porting the psql frontend as well, but I figured it was a good
idea to send in these patches first - so no major changes are done
to the files before it gets applied (if it does).

Regards,
  Magnus Hagander

I have implemented a framework of encoding translation between the
backend and the frontend. Also I have added a new variable setting
command:

SET CLIENT_ENCODING TO 'encoding';

Other features include:
	Latin1 support more 8 bit cleaness

See doc/README.mb for more details. Note that the pacthes are
against May 30 snapshot.

Tatsuo Ishii

code that I had assumed was working had not been tested.  Naturally,
it was broken ...

Tom Lane

1. Rewritten libpq to allow asynchronous clients.

2. Implemented client side of cancel protocol in library,
   and patched psql.c to send a cancel request upon SIGINT.  The
   backend doesn't notice it yet :-(

3. Implemented 'Z' protocol message addition and renaming of
   copy in/out start messages.  These are implemented conditionally,
   ie, the client protocol version is checked; so the code should
   still work with 1.0 clients.

4. Revised protocol and libpq sgml documents (don't have an SGML
   compiler, though, so there may be some markup glitches here).


What remains to be done:

1. Implement addition of atttypmod field to RowDescriptor messages.
   The client-side code is there but ifdef'd out.  I have no idea
   what to change on the backend side.  The field should be sent
   only if protocol >= 2.0, of course.

2. Implement backend response to cancel requests received as OOB
   messages.  (This prolly need not be conditional on protocol
   version; just do it if you get SIGURG.)

3. Update libpq.3.  (I'm hoping this can be generated mechanically
   from libpq.sgml... if not, will do it by hand.)  Is there any
   other doco to fix?

4. Update non-libpq interfaces as necessary.  I patched libpgtcl
   so that it would compile, but haven't tested it.  Dunno what
   needs to be done with the other interfaces.

Have at it!

Tom Lane

If PQfn() receives NOTICEs from the backend, it fails because there is no
provision to deal with them.

This patch (supplied by Anders Hammarquist <iko@netg.se> to me as Debian
maintainer of postgresql) cures the problem:

The following patch is to src/interfaces/libpq of postgresql-6.3.
The purpose of the patch is to make the initialization of
const char *pgresStatus[] match the ExecStatusType enum.

I've completed the patch to fix the protocol and authentication issues I
was discussing a couple of weeks ago.  The particular changes are:

- the protocol has a version number
- network byte order is used throughout
- the pg_hba.conf file is used to specify what method is used to
  authenticate a frontend (either password, ident, trust, reject, krb4
  or krb5)
- support for multiplexed backends is removed
- appropriate changes to man pages
- the -a switch to many programs to specify an authentication service
  no longer has any effect
- the libpq.so version number has changed to 1.1

The new backend still supports the old protocol so old interfaces won't
break.

 Most processors should optimize this a bit better wrt cache prefetch.

Document pg_dump -z, clean up option list.  Fix problem with libpq handling of field names uppercase code.

Another PGINDENT run that changes variable indenting and case label indenting.  Also static variable indenting.

Subject: [PATCHES] memory leak patches in libpq and psql

A couple of small memory leak patches (detected with Purify) primarily
in libpq.

* Fixed (NULL) border problem in psql (run psql, do \m, then select
  something from a table...row separators will be nulls)
* Fixed memory leak with the abovementioned border not being freed
  properly.
* Fixed memory leak in freePGconn() not freeing conn->port
* Fixed up PQclear() to free parts of PGresult only if these
  parts are not null.
* Fixed a decent memory leak that occured after executing every command
  in psql. PGresult *results was not freed most of the time.

There is still a leak being detected (2 bytes) in readline functions, but
I think this is old readline library. I will install new one and test it.

Made PQsetdb() and PQfnumber() case-insensitive.
Removed attempt to set table ownership via pg_dumpall.

#if defined(aix)
#define TERMIOS_H_LOCATION <termios.h>
#else
#define TERMIOS_H_LOCATION <sys/termios.h>
#endif

libpq/fe-exec.c modified so that location of termios.h is determined
by whether HAVE_TERMIOS_H is defined or not, in preparation for switch
to configure

Hi,

    counting the empty dummy queries in libpq isn't everything.
    If the backend sends an error, the I returns from the dummies
    still come. So we must eat them up in any case, not just
    returning on the occurence of an E reply.

Until later, Jan