Обсуждение: libpq++ fixes

This patch fixes a few minor problems with libpq++: remove the deprecated
PQExec(" ") in the wrapper around PQnotifies(), fix the Makefile for
the examples so that they will actually compile properly (with the
exception of #5, which depends on internal headers), make a minor change
to libpq++.h so that "make examples" now works on my machine, update
some documentation, fix some grammatical problems, and remove some of
the more hideous comments.

I plan on doing some more work on libpq++ in the future -- this patch just
consists of the necessary code to get the examples to compile on my machine,
plus corrections for any of the minor things I noticed on the way through.

Cheers,

Neil

--
Neil Conway <neilconway@rogers.com>
PGP Key ID: DB3C29FC

On Sat, May 18, 2002 at 06:57:25PM -0400, Neil Conway wrote:
>
> I plan on doing some more work on libpq++ in the future -- this patch just
> consists of the necessary code to get the examples to compile on my machine,
> plus corrections for any of the minor things I noticed on the way through.

You may also want to take a look at libpqxx, which was written to replace
libpq++.  It's been pretty solid so far, and it gets rid of a lot of the
design limitations of libpq++.  IMHO trying to fix libpq++ will not get
around all of its problems, which is why I rewrote libpqxx from scratch.
The code has proven pretty solid so far.

You'll find libpqxx at

    http://members.ams.chello.nl/j.vermeulen31/proj-libpqxx.html


Jeroen

On Sun, 19 May 2002 05:35:12 +0200
"jtv" <jtv@xs4all.nl> wrote:

> On Sat, May 18, 2002 at 06:57:25PM -0400, Neil Conway wrote:
> >
> > I plan on doing some more work on libpq++ in the future -- this patch just
> > consists of the necessary code to get the examples to compile on my machine,
> > plus corrections for any of the minor things I noticed on the way through.
>
> You may also want to take a look at libpqxx, which was written to replace
> libpq++.

Wow, looks great!

The website mentions your intention to get this code integrated into
the PostgreSQL tree -- when would you like to see this happen? I'd
definately vote in favour of it.

Cheers,

Neil

--
Neil Conway <neilconway@rogers.com>
PGP Key ID: DB3C29FC

On Sun, May 19, 2002 at 01:02:27AM -0400, Neil Conway wrote:
>
> The website mentions your intention to get this code integrated into
> the PostgreSQL tree -- when would you like to see this happen? I'd
> definately vote in favour of it.

I would _like_ to do it straight away, but I've set myself one more
milestone--a real-world application needs to be ported, to prove that
libpqxx can survive more than a mere regression test.  The idea is to
make this a dependable piece of code from day one.

Unfortunately I haven't had a lot of time to get the application I
wanted to port back into a compilable state on my platform (somebody
working on IPv6 support accidentally introduced a bunch of Solaris
function calls).  So I'm currently hoping for either the news that
some other application has been written / ported to use libpqxx, or
the time to do it myself.


Jeroen

Neil Conway writes:

> This patch fixes a few minor problems with libpq++: remove the deprecated
> PQExec(" ") in the wrapper around PQnotifies(), fix the Makefile for
> the examples so that they will actually compile properly (with the
> exception of #5, which depends on internal headers), make a minor change
> to libpq++.h so that "make examples" now works on my machine, update
> some documentation, fix some grammatical problems, and remove some of
> the more hideous comments.

Unfortunately, replacing #include <header.h> with #include <header> is
going to break a bunch of other platforms.

As for the formatting changes, maybe we should run pgindent over those
files.  It seems it has never been done.

--
Peter Eisentraut   peter_e@gmx.net

On Sun, 19 May 2002 17:14:23 +0200 (CEST)
"Peter Eisentraut" <peter_e@gmx.net> wrote:
> Neil Conway writes:
>
> > This patch fixes a few minor problems with libpq++: remove the deprecated
> > PQExec(" ") in the wrapper around PQnotifies(), fix the Makefile for
> > the examples so that they will actually compile properly (with the
> > exception of #5, which depends on internal headers), make a minor change
> > to libpq++.h so that "make examples" now works on my machine, update
> > some documentation, fix some grammatical problems, and remove some of
> > the more hideous comments.
>
> Unfortunately, replacing #include <header.h> with #include <header> is
> going to break a bunch of other platforms.

Really? Which ones?

> As for the formatting changes, maybe we should run pgindent over those
> files.  It seems it has never been done.

Yeah -- I was going to suggest that. But given how hideous most of
the libpq++ code is, and the availibility of a replacement for it
(see libpqxx), I'm not sure if it's worth the bother...

Cheers,

Neil

--
Neil Conway <neilconway@rogers.com>
PGP Key ID: DB3C29FC

Neil Conway <nconway@klamath.dyndns.org> writes:
> "Peter Eisentraut" <peter_e@gmx.net> wrote:
>> As for the formatting changes, maybe we should run pgindent over those
>> files.  It seems it has never been done.

> Yeah -- I was going to suggest that.

I think the reason Bruce doesn't do that is that pgindent doesn't know
anything about C++.

            regards, tom lane

On Sun, 19 May 2002 11:21:18 -0400
"Neil Conway" <nconway@klamath.dyndns.org> wrote:
> On Sun, 19 May 2002 17:14:23 +0200 (CEST)
> "Peter Eisentraut" <peter_e@gmx.net> wrote:
> > Unfortunately, replacing #include <header.h> with #include <header> is
> > going to break a bunch of other platforms.
>
> Really? Which ones?

In any case, I've attached a revised patch with #include <cppheader> changed
back to #include <cppheader.h>

Cheers,

Neil

--
Neil Conway <neilconway@rogers.com>
PGP Key ID: DB3C29FC

Your patch has been added to the PostgreSQL unapplied patches list at:

    http://candle.pha.pa.us/cgi-bin/pgpatches

I will try to apply it within the next 48 hours.

---------------------------------------------------------------------------


Neil Conway wrote:
> On Sun, 19 May 2002 11:21:18 -0400
> "Neil Conway" <nconway@klamath.dyndns.org> wrote:
> > On Sun, 19 May 2002 17:14:23 +0200 (CEST)
> > "Peter Eisentraut" <peter_e@gmx.net> wrote:
> > > Unfortunately, replacing #include <header.h> with #include <header> is
> > > going to break a bunch of other platforms.
> >
> > Really? Which ones?
>
> In any case, I've attached a revised patch with #include <cppheader> changed
> back to #include <cppheader.h>
>
> Cheers,
>
> Neil
>
> --
> Neil Conway <neilconway@rogers.com>
> PGP Key ID: DB3C29FC

[ Attachment, skipping... ]

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--
  Bruce Momjian                        |  http://candle.pha.pa.us
  pgman@candle.pha.pa.us               |  (610) 853-3000
  +  If your life is a hard drive,     |  830 Blythe Avenue
  +  Christ can be your backup.        |  Drexel Hill, Pennsylvania 19026

Patch applied:

This patch fixes a few minor problems with libpq++: remove the deprecated
PQExec(" ") in the wrapper around PQnotifies(), fix the Makefile for
the examples so that they will actually compile properly (with the
exception of #5, which depends on internal headers), make a minor change
to libpq++.h so that "make examples" now works on my machine, update
some documentation, fix some grammatical problems, and remove some of
the more hideous comments.

Neil Conway

---------------------------------------------------------------------------

Neil Conway wrote:
> On Sun, 19 May 2002 11:21:18 -0400
> "Neil Conway" <nconway@klamath.dyndns.org> wrote:
> > On Sun, 19 May 2002 17:14:23 +0200 (CEST)
> > "Peter Eisentraut" <peter_e@gmx.net> wrote:
> > > Unfortunately, replacing #include <header.h> with #include <header> is
> > > going to break a bunch of other platforms.
> >
> > Really? Which ones?
>
> In any case, I've attached a revised patch with #include <cppheader> changed
> back to #include <cppheader.h>
>
> Cheers,
>
> Neil
>
> --
> Neil Conway <neilconway@rogers.com>
> PGP Key ID: DB3C29FC

[ Attachment, skipping... ]

>
> ---------------------------(end of broadcast)---------------------------
> TIP 5: Have you checked our extensive FAQ?
>
> http://www.postgresql.org/users-lounge/docs/faq.html

--
  Bruce Momjian                        |  http://candle.pha.pa.us
  pgman@candle.pha.pa.us               |  (610) 853-3000
  +  If your life is a hard drive,     |  830 Blythe Avenue
  +  Christ can be your backup.        |  Drexel Hill, Pennsylvania 19026

(Oops, sent it to the wrong thread last time.)

If on one is has outstanding libpq++ patches, I will run libpq++ through
my new tools src/tools/pgindent/pgcppindent.  It uses astyle.  I can
also wait for 7.3 beta and run it then.

Sample changes attached.

---------------------------------------------------------------------------

Neil Conway wrote:
> This patch fixes a few minor problems with libpq++: remove the deprecated
> PQExec(" ") in the wrapper around PQnotifies(), fix the Makefile for
> the examples so that they will actually compile properly (with the
> exception of #5, which depends on internal headers), make a minor change
> to libpq++.h so that "make examples" now works on my machine, update
> some documentation, fix some grammatical problems, and remove some of
> the more hideous comments.
>
> I plan on doing some more work on libpq++ in the future -- this patch just
> consists of the necessary code to get the examples to compile on my machine,
> plus corrections for any of the minor things I noticed on the way through.
>
> Cheers,
>
> Neil
>
> --
> Neil Conway <neilconway@rogers.com>
> PGP Key ID: DB3C29FC

[ Attachment, skipping... ]

>
> ---------------------------(end of broadcast)---------------------------
> TIP 4: Don't 'kill -9' the postmaster

--
  Bruce Momjian                        |  http://candle.pha.pa.us
  pgman@candle.pha.pa.us               |  (610) 853-3000
  +  If your life is a hard drive,     |  830 Blythe Avenue
  +  Christ can be your backup.        |  Drexel Hill, Pennsylvania 19026
Index: pgconnection.cc
===================================================================
RCS file: /cvsroot/pgsql/src/interfaces/libpq++/pgconnection.cc,v
retrieving revision 1.14
diff -c -r1.14 pgconnection.cc
*** pgconnection.cc    15 Jun 2002 18:49:29 -0000    1.14
--- pgconnection.cc    15 Jun 2002 19:05:11 -0000
***************
*** 1,19 ****
  /*-------------------------------------------------------------------------
!  *
!  *   FILE
!  *    pgconnection.cc
!  *
!  *   DESCRIPTION
!  *      implementation of the PgConnection class.
!  *   PgConnection encapsulates a frontend to backend connection
!  *
!  * Copyright (c) 1994, Regents of the University of California
!  *
!  * IDENTIFICATION
!  *      $Header: /cvsroot/pgsql/src/interfaces/libpq++/pgconnection.cc,v 1.14 2002/06/15 18:49:29 momjian Exp $
!  *
!  *-------------------------------------------------------------------------
!  */

  #include "pgconnection.h"

--- 1,19 ----
  /*-------------------------------------------------------------------------
! *
! *    FILE
! *    pgconnection.cc
! *
! *    DESCRIPTION
! *       implementation of the PgConnection class.
! *    PgConnection encapsulates a frontend to backend connection
! *
! * Copyright (c) 1994, Regents of the University of California
! *
! * IDENTIFICATION
! *      $Header: /cvsroot/pgsql/src/interfaces/libpq++/pgconnection.cc,v 1.14 2002/06/15 18:49:29 momjian Exp $
! *
! *-------------------------------------------------------------------------
! */

  #include "pgconnection.h"

***************
*** 28,71 ****
  // ****************************************************************
  // default constructor -- initialize everything
  PgConnection::PgConnection()
!     : pgConn(NULL), pgResult(NULL), pgCloseConnection(false)
  {}


  // constructor -- checks environment variable for database name
  // Now uses PQconnectdb
  PgConnection::PgConnection(const char* conninfo)
!     : pgConn(NULL), pgResult(NULL), pgCloseConnection(true)
  {
!   // Connect to the database
!   Connect(conninfo);
  }


  // destructor - closes down the connection and cleanup
  PgConnection::~PgConnection()
  {
!   // Close the connection only if needed
!   // This feature will most probably be used by the derived classes that
!   // need not close the connection after they are destructed.
!   CloseConnection();
  }


  // PgConnection::CloseConnection()
  // close down the connection if there is one
! void PgConnection::CloseConnection()
  {
!   // if the connection is open, close it first
!   if (pgCloseConnection) {
!        if (pgResult)
!            PQclear(pgResult);
!        pgResult = NULL;
!        if (pgConn)
!            PQfinish(pgConn);
!        pgConn = NULL;
!        pgCloseConnection = false;
!   }
  }


--- 28,73 ----
  // ****************************************************************
  // default constructor -- initialize everything
  PgConnection::PgConnection()
!         : pgConn(NULL), pgResult(NULL), pgCloseConnection(false)
  {}


  // constructor -- checks environment variable for database name
  // Now uses PQconnectdb
+
  PgConnection::PgConnection(const char* conninfo)
!         : pgConn(NULL), pgResult(NULL), pgCloseConnection(true)
  {
!     // Connect to the database
!     Connect(conninfo);
  }


  // destructor - closes down the connection and cleanup
  PgConnection::~PgConnection()
  {
!     // Close the connection only if needed
!     // This feature will most probably be used by the derived classes that
!     // need not close the connection after they are destructed.
!     CloseConnection();
  }


  // PgConnection::CloseConnection()
  // close down the connection if there is one
! void PgConnection::CloseConnection()
  {
!     // if the connection is open, close it first
!     if (pgCloseConnection)
!     {
!         if (pgResult)
!             PQclear(pgResult);
!         pgResult = NULL;
!         if (pgConn)
!             PQfinish(pgConn);
!         pgConn = NULL;
!         pgCloseConnection = false;
!     }
  }


***************
*** 73,112 ****
  // establish a connection to a backend
  ConnStatusType PgConnection::Connect(const char conninfo[])
  {
!   // if the connection is open, close it first
!   CloseConnection();

!   // Connect to the database
!   pgConn = PQconnectdb(conninfo);

!   // Now we have a connection we must close (even if it's bad!)
!   pgCloseConnection = true;
!
!   // Status will return either CONNECTION_OK or CONNECTION_BAD
!   return Status();
  }

  // PgConnection::status -- return connection or result status
  ConnStatusType PgConnection::Status() const
  {
!   return PQstatus(pgConn);
  }

  // PgConnection::exec  -- send a query to the backend
  ExecStatusType PgConnection::Exec(const char* query)
  {
!   // Clear the result stucture if needed
!   if (pgResult)
!     PQclear(pgResult);
!
!   // Execute the given query
!   pgResult = PQexec(pgConn, query);
!
!   // Return the status
!   if (pgResult)
!     return PQresultStatus(pgResult);
!   else
!     return PGRES_FATAL_ERROR;
  }

  // Return true if the Postgres command was executed OK
--- 75,114 ----
  // establish a connection to a backend
  ConnStatusType PgConnection::Connect(const char conninfo[])
  {
!     // if the connection is open, close it first
!     CloseConnection();
!
!     // Connect to the database
!     pgConn = PQconnectdb(conninfo);

!     // Now we have a connection we must close (even if it's bad!)
!     pgCloseConnection = true;

!     // Status will return either CONNECTION_OK or CONNECTION_BAD
!     return Status();
  }

  // PgConnection::status -- return connection or result status
  ConnStatusType PgConnection::Status() const
  {
!     return PQstatus(pgConn);
  }

  // PgConnection::exec  -- send a query to the backend
  ExecStatusType PgConnection::Exec(const char* query)
  {
!     // Clear the result stucture if needed
!     if (pgResult)
!         PQclear(pgResult);
!
!     // Execute the given query
!     pgResult = PQexec(pgConn, query);
!
!     // Return the status
!     if (pgResult)
!         return PQresultStatus(pgResult);
!     else
!         return PGRES_FATAL_ERROR;
  }

  // Return true if the Postgres command was executed OK
***************
*** 125,158 ****
  // PgConnection::notifies() -- returns a notification from a list of unhandled notifications
  PGnotify* PgConnection::Notifies()
  {
!   return PQnotifies(pgConn);
  }

  // From Integer To String Conversion Function
  string PgConnection::IntToString(int n)
  {
!   char buffer [4*sizeof(n) + 2];
!   sprintf(buffer, "%d", n);
!   return buffer;
  }

  bool PgConnection::ConnectionBad() const
! {
!   return Status() == CONNECTION_BAD;
  }

  const char* PgConnection::ErrorMessage() const
! {
!   return (const char *)PQerrorMessage(pgConn);
  }
!
  const char* PgConnection::DBName() const
! {
!   return (const char *)PQdb(pgConn);
  }

  PQnoticeProcessor PgConnection::SetNoticeProcessor(PQnoticeProcessor proc, void *arg)
  {
!   return PQsetNoticeProcessor(pgConn, proc, arg);
  }

--- 127,160 ----
  // PgConnection::notifies() -- returns a notification from a list of unhandled notifications
  PGnotify* PgConnection::Notifies()
  {
!     return PQnotifies(pgConn);
  }

  // From Integer To String Conversion Function
  string PgConnection::IntToString(int n)
  {
!     char buffer [4*sizeof(n) + 2];
!     sprintf(buffer, "%d", n);
!     return buffer;
  }

  bool PgConnection::ConnectionBad() const
! {
!     return Status() == CONNECTION_BAD;
  }

  const char* PgConnection::ErrorMessage() const
! {
!     return (const char *)PQerrorMessage(pgConn);
  }
!
  const char* PgConnection::DBName() const
! {
!     return (const char *)PQdb(pgConn);
  }

  PQnoticeProcessor PgConnection::SetNoticeProcessor(PQnoticeProcessor proc, void *arg)
  {
!     return PQsetNoticeProcessor(pgConn, proc, arg);
  }

On Sat, Jun 15, 2002 at 03:16:19PM -0400, Bruce Momjian wrote:
>
> If on one is has outstanding libpq++ patches, I will run libpq++ through
> my new tools src/tools/pgindent/pgcppindent.  It uses astyle.  I can
> also wait for 7.3 beta and run it then.

Which reminds me--is it a problem for me to maintain my own indentation
style in libpqxx?


Jeroen

jtv wrote:
> On Sat, Jun 15, 2002 at 03:16:19PM -0400, Bruce Momjian wrote:
> >
> > If on one is has outstanding libpq++ patches, I will run libpq++ through
> > my new tools src/tools/pgindent/pgcppindent.  It uses astyle.  I can
> > also wait for 7.3 beta and run it then.
>
> Which reminds me--is it a problem for me to maintain my own indentation
> style in libpqxx?

It is up to you.  If you want to, go ahead.  We only auto-indent stuff
that needs consistent indenting.  If you already have that, and want to
maintain it, you are welcome.

--
  Bruce Momjian                        |  http://candle.pha.pa.us
  pgman@candle.pha.pa.us               |  (610) 853-3000
  +  If your life is a hard drive,     |  830 Blythe Avenue
  +  Christ can be your backup.        |  Drexel Hill, Pennsylvania 19026