This patch (against the current CVS sources) adds to libpq the functions

PQconnectStart
PQconnectPoll
PQresetStart
PQresetPoll
PQsetenvStart
PQsetenvPoll
PQsetenvAbort

and brings into the published interface

PQsetenv.

The first four are asynchronous analogues of PQconnectdb and PQreset -
they allow an application to connect to the DB without blocking on
remote I/O.

The PQsetenv functions perform an environment negotiation with the
server.

Internal to libpq, pqReadReady and pqWriteReady have been made available
across the library (they were previously static functions inside
fe-misc.c).  A lot of internal rearrangement has been necessary to
support these changes.

The API documentation has been updated also.

Caveats:

  o  The Windows code does not default to using non-blocking sockets,
since I have no documentation: Define WIN32_NON_BLOCKING_CONNECTIONS to
do that.

  o  The SSL code still blocks.


Ewan Mellor.

1 files changed, 1050 insertions, 238 deletions

diff --git a/src/interfaces/libpq/fe-connect.c b/src/interfaces/libpq/fe-connect.c
index 7e2fb443797..85764b1e9d4 100644
--- a/src/interfaces/libpq/fe-connect.c
+++ b/src/interfaces/libpq/fe-connect.c
@@ -7,11 +7,13 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/interfaces/libpq/fe-connect.c,v 1.106 1999/11/11 00:10:13 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/interfaces/libpq/fe-connect.c,v 1.107 1999/11/30 03:08:18 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
 
+#include <sys/types.h>
+#include <sys/socket.h>
 #include <fcntl.h>
 #include <errno.h>
 #include <ctype.h>
@@ -27,6 +29,7 @@
 #include <unistd.h>
 #include <netdb.h>
 #include <netinet/tcp.h>
+#include <arpa/inet.h>
 #endif
 
 #ifndef HAVE_STRDUP
@@ -40,11 +43,37 @@
 #include "mb/pg_wchar.h"
 #endif
 
+/* ----------
+ *     pg_setenv_state
+ * A struct used when polling a setenv request. This is referred to externally
+ * using a PGsetenvHandle.
+ * ----------
+ */
+struct pg_setenv_state
+{
+	enum
+	{
+		SETENV_STATE_OPTION_SEND,    /* About to send an Environment Option */
+		SETENV_STATE_OPTION_WAIT,    /* Waiting for above send to complete  */
+#ifdef MULTIBYTE
+		SETENV_STATE_ENCODINGS_SEND, /* About to send an "encodings" query  */
+		SETENV_STATE_ENCODINGS_WAIT, /* Waiting for query to complete       */
+#endif
+		SETENV_STATE_OK,
+		SETENV_STATE_FAILED
+	} state;
+	PGconn *conn;
+	PGresult *res;
+	struct EnvironmentOptions *eo;
+} ;
+
+static int connectDBStart(PGconn *conn);
+static int connectDBComplete(PGconn *conn);
+
 #ifdef USE_SSL
 static SSL_CTX *SSL_context = NULL;
 #endif
 
-static ConnStatusType connectDB(PGconn *conn);
 static PGconn *makeEmptyPGconn(void);
 static void freePGconn(PGconn *conn);
 static void closePGconn(PGconn *conn);
@@ -53,9 +82,6 @@ static char *conninfo_getval(char *keyword);
 static void conninfo_free(void);
 static void defaultNoticeProcessor(void *arg, const char *message);
 
-/* XXX Why is this not static? */
-void		PQsetenv(PGconn *conn);
-
 #define NOTIFYLIST_INITIAL_SIZE 10
 #define NOTIFYLIST_GROWBY 10
 
@@ -98,6 +124,9 @@ static PQconninfoOption PQconninfoOptions[] = {
 	{"host", "PGHOST", NULL, NULL,
 	"Database-Host", "", 40},
 
+	{"hostaddr", "PGHOSTADDR", NULL, NULL,
+	 "Database-Host-IPv4-Address", "", 15}, /* Room for abc.def.ghi.jkl */
+
 	{"port", "PGPORT", DEF_PGPORT, NULL,
 	"Database-Port", "", 6},
 
@@ -145,28 +174,87 @@ static struct EnvironmentOptions
 	}
 };
 
+
+/* ----------------
+ *      Connecting to a Database
+ *
+ * There are now four different ways a user of this API can connect to the
+ * database.  Two are not recommended for use in new code, because of their
+ * lack of extensibility with respect to the passing of options to the
+ * backend.  These are PQsetdb and PQsetdbLogin (the former now being a macro
+ * to the latter).
+ *
+ * If it is desired to connect in a synchronous (blocking) manner, use the
+ * function PQconnectdb.
+ *
+ * To connect in an asychronous (non-blocking) manner, use the functions
+ * PQconnectStart, and PQconnectPoll.
+ *
+ * Internally, the static functions connectDBStart, connectDBComplete
+ * are part of the connection procedure.
+ * 
+ * ----------------
+ */
+
 /* ----------------
  *		PQconnectdb
  *
  * establishes a connection to a postgres backend through the postmaster
  * using connection information in a string.
  *
- * The conninfo string is a list of
+ * The conninfo string is a white-separated list of
  *
  *	   option = value
  *
- * definitions. Value might be a single value containing no whitespaces
- * or a single quoted string. If a single quote should appear everywhere
- * in the value, it must be escaped with a backslash like \'
+ * definitions. Value might be a single value containing no whitespaces or
+ * a single quoted string. If a single quote should appear anywhere in
+ * the value, it must be escaped with a backslash like \'
  *
- * Returns a PGconn* which is needed for all subsequent libpq calls
- * if the status field of the connection returned is CONNECTION_BAD,
- * then some fields may be null'ed out instead of having valid values
- * ----------------
- */
+ * Returns a PGconn* which is needed for all subsequent libpq calls, or NULL
+ * if a memory allocation failed.
+ * If the status field of the connection returned is CONNECTION_BAD,
+ * then some fields may be null'ed out instead of having valid values.
+ *
+ * You should call PQfinish (if conn is not NULL) regardless of whether this
+ * call succeeded.
+ *
+ * ---------------- */
+
 PGconn *
 PQconnectdb(const char *conninfo)
 {
+	PGconn *conn = PQconnectStart(conninfo);
+	
+	(void)(!conn || (conn->status == CONNECTION_BAD) ||
+		   !connectDBComplete(conn));
+
+	return conn;
+}
+
+/* ----------------
+ *		PQconnectStart
+ *
+ * Begins the establishment of a connection to a postgres backend through the
+ * postmaster using connection information in a string.
+ *
+ * See comment for PQconnectdb for the definition of the string format.
+ *
+ * Returns a PGconn*.  If NULL is returned, a malloc error has occurred, and
+ * you should not attempt to proceed with this connection.  If the status
+ * field of the connection returned is CONNECTION_BAD, an error has
+ * occurred. In this case you should call PQfinish on the result, (perhaps
+ * inspecting the error message first).  Other fields of the structure may not
+ * be valid if that occurs.  If the status field is not CONNECTION_BAD, then
+ * this stage has succeeded - call PQconnectPoll, using select(2) to see when
+ * this is necessary.
+ *
+ * See PQconnectPoll for more info.
+ *
+ * ---------------- */
+
+PGconn *
+PQconnectStart(const char *conninfo)
+{
 	PGconn	   *conn;
 	char	   *tmp;
 
@@ -174,6 +262,7 @@ PQconnectdb(const char *conninfo)
 	 * Allocate memory for the conn structure
 	 * ----------
 	 */
+	
 	conn = makeEmptyPGconn();
 	if (conn == NULL)
 		return (PGconn *) NULL;
@@ -188,6 +277,8 @@ PQconnectdb(const char *conninfo)
 		conninfo_free();
 		return conn;
 	}
+	tmp = conninfo_getval("hostaddr");
+	conn->pghostaddr = tmp ? strdup(tmp) : NULL;
 	tmp = conninfo_getval("host");
 	conn->pghost = tmp ? strdup(tmp) : NULL;
 	tmp = conninfo_getval("port");
@@ -213,7 +304,11 @@ PQconnectdb(const char *conninfo)
 	 * Connect to the database
 	 * ----------
 	 */
-	conn->status = connectDB(conn);
+	if (!connectDBStart(conn))
+	{
+	  /* Just in case we failed to set it in connectDBStart */
+		conn->status = CONNECTION_BAD;
+	}
 
 	return conn;
 }
@@ -384,10 +479,14 @@ PQsetdbLogin(const char *pghost, const char *pgport, const char *pgoptions, cons
 	}
 
 	if (error)
+	{
 		conn->status = CONNECTION_BAD;
+	}
 	else
-		conn->status = connectDB(conn);
-
+	{
+		(void)(!connectDBStart(conn) || !connectDBComplete(conn));
+	}
+		
 	return conn;
 }
 
@@ -480,7 +579,9 @@ update_db_info(PGconn *conn)
 				if (strcmp(old + offset, "localhost") != 0)
 				{
 					printfPQExpBuffer(&conn->errorMessage,
-									  "connectDB() -- non-tcp access only possible on localhost\n");
+									  "connectDBStart() -- "
+									  "non-tcp access only possible on "
+									  "localhost\n");
 					return 1;
 				}
 			}
@@ -494,24 +595,84 @@ update_db_info(PGconn *conn)
 	return 0;
 }
 
-/*
- * connectDB -
- * make a connection to the backend so it is ready to receive queries.
- * return CONNECTION_OK if successful, CONNECTION_BAD if not.
- *
+
+/* ----------
+ * connectMakeNonblocking -
+ * Make a connection non-blocking.
+ * Returns 1 if successful, 0 if not.
+ * ----------
  */
-static ConnStatusType
-connectDB(PGconn *conn)
+static int
+connectMakeNonblocking(PGconn *conn)
+{
+#ifndef WIN32
+	if (fcntl(conn->sock, F_SETFL, O_NONBLOCK) < 0)
+#else
+	if (ioctlsocket(conn->sock, FIONBIO, &on) != 0)
+#endif
+	{
+		printfPQExpBuffer(&conn->errorMessage,
+						  "connectMakeNonblocking -- fcntl() failed: errno=%d\n%s\n",
+						  errno, strerror(errno));
+		return 0;
+	}
+
+	return 1;
+}
+
+/* ----------
+ * connectNoDelay -
+ * Sets the TCP_NODELAY socket option.
+ * Returns 1 if successful, 0 if not.
+ * ----------
+ */
+static int
+connectNoDelay(PGconn *conn)
+{
+	struct protoent *pe;
+	int			on = 1;
+
+	pe = getprotobyname("TCP");
+	if (pe == NULL)
+	{
+		printfPQExpBuffer(&conn->errorMessage,
+						  "connectNoDelay() -- "
+						  "getprotobyname failed: errno=%d\n%s\n",
+						  errno, strerror(errno));
+		return 0;
+	}
+	if (setsockopt(conn->sock, pe->p_proto, TCP_NODELAY,
+#ifdef WIN32
+				   (char *)
+#endif
+				   &on,
+				   sizeof(on)) < 0)
+	{
+		printfPQExpBuffer(&conn->errorMessage,
+						  "connectNoDelay() -- setsockopt failed: errno=%d\n%s\n",
+						  errno, strerror(errno));
+#ifdef WIN32
+		printf("Winsock error: %i\n", WSAGetLastError());
+#endif
+		return 0;
+	}
+
+	return 1;
+}
+
+
+/* ----------
+ * connectDBStart -
+ * Start to make a connection to the backend so it is ready to receive
+ * queries.
+ * Returns 1 if successful, 0 if not.
+ * ----------
+ */
+static int
+connectDBStart(PGconn *conn)
 {
-	PGresult   *res;
-	struct hostent *hp;
-	StartupPacket sp;
-	AuthRequest areq;
-	SOCKET_SIZE_TYPE laddrlen;
 	int			portno,
 				family;
-	char		beresp;
-	int			on = 1;
 #ifdef USE_SSL
 	StartupPacket           np; /* Used to negotiate SSL connection */
 	char                    SSLok;
@@ -519,92 +680,126 @@ connectDB(PGconn *conn)
 	int                     tried_ssl = 0;      /* Set if SSL negotiation was tried */
 #endif
 
+	if (!conn)
+		return 0;
 	/*
 	 * parse dbName to get all additional info in it, if any
 	 */
 	if (update_db_info(conn) != 0)
 		goto connect_errReturn;
 
+	/* Ensure our buffers are empty */
+	conn->inStart = conn->inCursor = conn->inEnd = 0;
+	conn->outCount = 0;
+
 	/*
-	 * Initialize the startup packet.
+	 * Set up the connection to postmaster/backend.
+	 * Note that this supports IPv4 and UDP only.
 	 */
 
-	MemSet((char *) &sp, 0, sizeof(StartupPacket));
-
-	sp.protoVersion = (ProtocolVersion) htonl(PG_PROTOCOL_LIBPQ);
+	MemSet((char *) &conn->raddr, 0, sizeof(conn->raddr));
 
-	strncpy(sp.user, conn->pguser, SM_USER);
-	strncpy(sp.database, conn->dbName, SM_DATABASE);
-	strncpy(sp.tty, conn->pgtty, SM_TTY);
+	if (conn->pghostaddr != NULL)
+	{
+		/* Using pghostaddr avoids a hostname lookup */
+		/* Note that this supports IPv4 only */
+		struct in_addr addr;
 
-	if (conn->pgoptions)
-		strncpy(sp.options, conn->pgoptions, SM_OPTIONS);
+		if(!inet_aton(conn->pghostaddr, &addr))
+		{
+			printfPQExpBuffer(&conn->errorMessage,
+							  "connectDBStart() -- "
+							  "invalid host address: %s\n", conn->pghostaddr);
+			goto connect_errReturn;
+		}
 
-	/*
-	 * Open a connection to postmaster/backend.
-	 */
+		family = AF_INET;
 
-	if (conn->pghost != NULL)
+		memmove((char *) &(conn->raddr.in.sin_addr),
+				(char *) &addr, sizeof(addr));
+	}
+	else if (conn->pghost != NULL)
 	{
+		/* Using pghost, so we have to look-up the hostname */
+		struct hostent *hp;
+
 		hp = gethostbyname(conn->pghost);
 		if ((hp == NULL) || (hp->h_addrtype != AF_INET))
 		{
 			printfPQExpBuffer(&conn->errorMessage,
-							  "connectDB() --  unknown hostname: %s\n",
+							  "connectDBStart() --  unknown hostname: %s\n",
 							  conn->pghost);
 			goto connect_errReturn;
 		}
 		family = AF_INET;
+
+		memmove((char *) &(conn->raddr.in.sin_addr),
+				(char *) hp->h_addr,
+				hp->h_length);
 	}
 	else
 	{
-		hp = NULL;
+		/* pghostaddr and pghost are NULL, so use UDP */
 		family = AF_UNIX;
 	}
 
-	MemSet((char *) &conn->raddr, 0, sizeof(conn->raddr));
+	/* Set family */
 	conn->raddr.sa.sa_family = family;
 
+	/* Set port number */
 	portno = atoi(conn->pgport);
 	if (family == AF_INET)
 	{
-		memmove((char *) &(conn->raddr.in.sin_addr),
-				(char *) hp->h_addr,
-				hp->h_length);
 		conn->raddr.in.sin_port = htons((unsigned short) (portno));
 		conn->raddr_len = sizeof(struct sockaddr_in);
 	}
 #if !defined(WIN32) && !defined(__CYGWIN32__)
-	else
-		conn->raddr_len = UNIXSOCK_PATH(conn->raddr.un, portno);
+		else
+			conn->raddr_len = UNIXSOCK_PATH(conn->raddr.un, portno);
 #endif
 
 
-	/* Connect to the server  */
+	/* Open a socket */
 	if ((conn->sock = socket(family, SOCK_STREAM, 0)) < 0)
 	{
 		printfPQExpBuffer(&conn->errorMessage,
-						  "connectDB() -- socket() failed: errno=%d\n%s\n",
+						  "connectDBStart() -- "
+						  "socket() failed: errno=%d\n%s\n",
 						  errno, strerror(errno));
 		goto connect_errReturn;
 	}
-	if (connect(conn->sock, &conn->raddr.sa, conn->raddr_len) < 0)
+
+	/* ----------
+	 * Set the right options. Normally, we need nonblocking I/O, and we don't
+	 * want delay of outgoing data for AF_INET sockets.  If we are using SSL,
+	 * then we need the blocking I/O (XXX Can this be fixed?).
+	 * ---------- */
+
+	if (family == AF_INET)
 	{
-		printfPQExpBuffer(&conn->errorMessage,
-						  "connectDB() -- connect() failed: %s\n"
-						  "Is the postmaster running%s at '%s' and accepting connections on %s '%s'?\n",
-						  strerror(errno),
-						  (family == AF_INET) ? " (with -i)" : "",
-						  conn->pghost ? conn->pghost : "localhost",
-						  (family == AF_INET) ? "TCP/IP port" : "Unix socket",
-						  conn->pgport);
-		goto connect_errReturn;
+		if (!connectNoDelay(conn))
+			goto connect_errReturn;
 	}
 
+	/* ----------
+	 * Since I have no idea whether this is a valid thing to do under Windows
+	 * before a connection is made, and since I have no way of testing it, I
+	 * leave the code looking as below.  When someone decides that they want
+	 * non-blocking connections under Windows, they can define
+	 * WIN32_NON_BLOCKING_CONNECTIONS before compilation.  If it works, then
+	 * this code can be cleaned up.
+	 *
+	 *   Ewan Mellor <eem21@cam.ac.uk>.
+	 * ---------- */
+#if (!defined(WIN32) || defined(WIN32_NON_BLOCKING_CONNECTIONS)) && !defined(USE_SSL)
+	if (!connectMakeNonblocking(conn))
+		goto connect_errReturn;
+#endif	
+
+#ifdef USE_SSL
 	/* This needs to be done before we set into nonblocking, since SSL negotiation
 	 * does not like that mode */
 
-#ifdef USE_SSL
 	/* Attempt to negotiate SSL usage */
 	if (allow_ssl_try) {
 	  tried_ssl = 1;
@@ -653,7 +848,7 @@ connectDB(PGconn *conn)
 	      fprintf(conn->Pfdebug, "Backend reports error, attempting fallback to pre-6.6.\n");
 	    close(conn->sock);
 	    allow_ssl_try = 0;
-	    return connectDB(conn);
+	    return connectDBStart(conn);
 	  }
 	  else if (SSLok != 'N') {
 	    strcpy(conn->errorMessage,
@@ -665,242 +860,812 @@ connectDB(PGconn *conn)
 	  allow_ssl_try = 1; /* We'll allow an attempt to use SSL next time */
 #endif
 
-	/*
-	 * Set the right options. We need nonblocking I/O, and we don't want
-	 * delay of outgoing data.
+	/* ----------
+     * Start / make connection.  We are hopefully in non-blocking mode
+	 * now, but it is possible that:
+	 *   1. Older systems will still block on connect, despite the
+	 *      non-blocking flag. (Anyone know if this is true?)
+	 *   2. We are running under Windows, and aren't even trying
+	 *      to be non-blocking (see above).
+	 *   3. We are using SSL.
+	 * Thus, we have make arrangements for all eventualities.
+	 * ----------
 	 */
-
-#ifndef WIN32
-	if (fcntl(conn->sock, F_SETFL, O_NONBLOCK) < 0)
-#else
-	if (ioctlsocket(conn->sock, FIONBIO, &on) != 0)
-#endif
-	{
-		printfPQExpBuffer(&conn->errorMessage,
-						  "connectDB() -- fcntl() failed: errno=%d\n%s\n",
-						  errno, strerror(errno));
-		goto connect_errReturn;
-	}
-
-	if (family == AF_INET)
+	if (connect(conn->sock, &conn->raddr.sa, conn->raddr_len) < 0)
 	{
-		struct protoent *pe;
-
-		pe = getprotobyname("TCP");
-		if (pe == NULL)
+		if (errno == EINPROGRESS)
 		{
-			printfPQExpBuffer(&conn->errorMessage,
-							  "connectDB(): getprotobyname failed\n");
-			goto connect_errReturn;
+			/* This is fine - we're in non-blocking mode, and the
+			 * connection is in progress. */
+			conn->status = CONNECTION_STARTED;
 		}
-		if (setsockopt(conn->sock, pe->p_proto, TCP_NODELAY,
-#ifdef WIN32
-					   (char *)
-#endif
-					   &on,
-					   sizeof(on)) < 0)
+		else
 		{
+			/* Something's gone wrong */
 			printfPQExpBuffer(&conn->errorMessage,
-							  "connectDB() -- setsockopt failed: errno=%d\n%s\n",
-							  errno, strerror(errno));
-#ifdef WIN32
-			printf("Winsock error: %i\n", WSAGetLastError());
-#endif
+							  "connectDBStart() -- connect() failed: %s\n"
+							  "Is the postmaster running%s at '%s' "
+							  "and accepting connections on %s '%s'?\n",
+							  strerror(errno),
+							  (family == AF_INET) ? " (with -i)" : "",
+							  conn->pghost ? conn->pghost : "localhost",
+							  (family == AF_INET) ?
+							  "TCP/IP port" : "Unix socket",
+							  conn->pgport);
 			goto connect_errReturn;
 		}
 	}
-
-	/* Fill in the client address */
-	laddrlen = sizeof(conn->laddr);
-	if (getsockname(conn->sock, &conn->laddr.sa, &laddrlen) < 0)
+	else
 	{
-		printfPQExpBuffer(&conn->errorMessage,
-						  "connectDB() -- getsockname() failed: errno=%d\n%s\n",
-						  errno, strerror(errno));
-		goto connect_errReturn;
+		/* We're connected already */
+		conn->status = CONNECTION_MADE;
 	}
 
-	/* Ensure our buffers are empty */
-	conn->inStart = conn->inCursor = conn->inEnd = 0;
-	conn->outCount = 0;
+	/* This makes the connection non-blocking, for all those cases which forced us
+	   not to do it above. */
+#if (defined(WIN32) && !defined(WIN32_NON_BLOCKING_CONNECTIONS)) || defined(USE_SSL)
+	if (!connectMakeNonblocking(conn))
+		goto connect_errReturn;
+#endif	
 
-	/* Send the startup packet. */
+	return 1;
 
-	if (pqPacketSend(conn, (char *) &sp, sizeof(StartupPacket)) != STATUS_OK)
+connect_errReturn:
+	if (conn->sock >= 0)
 	{
-		printfPQExpBuffer(&conn->errorMessage,
-						  "connectDB() --  couldn't send startup packet: errno=%d\n%s\n",
-						  errno, strerror(errno));
-		goto connect_errReturn;
+#ifdef WIN32
+		closesocket(conn->sock);
+#else
+		close(conn->sock);
+#endif
+		conn->sock = -1;
 	}
+	conn->status = CONNECTION_BAD;
 
-	/*
-	 * Perform the authentication exchange: wait for backend messages and
-	 * respond as necessary. We fall out of this loop when done talking to
-	 * the postmaster.
-	 */
+	return 0;
+}
 
-	for (;;)
-	{
-		/* Wait for some data to arrive (or for the channel to close) */
-		if (pqWait(TRUE, FALSE, conn))
-			goto connect_errReturn;
-		/* Load data, or detect EOF */
-		if (pqReadData(conn) < 0)
-			goto connect_errReturn;
 
-		/*
-		 * Scan the message. If we run out of data, loop around to try
-		 * again.
-		 */
-		conn->inCursor = conn->inStart;
+/* ----------------
+ *		connectDBComplete
+ *
+ * Block and complete a connection.
+ *
+ * Returns 1 on success, 0 on failure.
+ * ----------------
+ */
+static int
+connectDBComplete(PGconn *conn)
+{
+	PostgresPollingStatusType flag;
+	int r = 0, w = 1;
 
-		if (pqGetc(&beresp, conn))
-			continue;			/* no data yet */
+	do
+	{
+		if(pqWait(r, w, conn))
+		{
+			conn->status = CONNECTION_BAD;
+			return 0;
+		}
 
-		/* Handle errors. */
-		if (beresp == 'E')
+	again:
+		switch(flag = PQconnectPoll(conn))
 		{
-			if (pqGets(&conn->errorMessage, conn))
-				continue;
-			goto connect_errReturn;
+			case PGRES_POLLING_ACTIVE:
+				goto again;
+
+			case PGRES_POLLING_OK:
+				break;
+				
+			case PGRES_POLLING_READING:
+				r = 1;
+				w = 0;
+				break;
+
+			case PGRES_POLLING_WRITING:
+				r = 0;
+				w = 1;
+				break;
+
+			default:
+				/* Just in case we failed to set it in PQconnectPoll */
+				conn->status = CONNECTION_BAD;
+				return 0;
 		}
+	} while (flag != PGRES_POLLING_OK);
+	
+	return 1;
+}
+
+
+/* ----------------
+ *		PQconnectPoll
+ *
+ * Poll an asynchronous connection.
+ *
+ * Returns a PostgresPollingStatusType.
+ * Before calling this function, use select(2) to determine when data arrive.
+ * 
+ * You must call PQfinish whether or not this fails.
+ *
+ * This function and PQconnectStart are intended to allow connections to be
+ * made without blocking the execution of your program on remote I/O. However,
+ * there are a number of caveats:
+ *
+ *   o  If you call PQtrace, ensure that the stream object into which you trace
+        will not block.
+ *   o  If you do not supply an IP address for the remote host (i.e. you 
+ *      supply a host name instead) then this function will block on
+ *      gethostbyname.  You will be fine if using UDP (i.e. by supplying
+ *      neither a host name nor a host address).
+ *   o  If your backend wants to use Kerberos authentication then you must
+ *      supply both a host name and a host address, otherwise this function
+ *      may block on gethostname.
+ *   o  This function will block if compiled with USE_SSL.
+ *
+ * ---------------- */
+PostgresPollingStatusType
+PQconnectPoll(PGconn *conn)
+{
+	PGresult   *res;
 
-		/* Otherwise it should be an authentication request. */
-		if (beresp != 'R')
+	if (conn == NULL)
+		return PGRES_POLLING_FAILED;
+
+	/* Get the new data */
+	switch (conn->status)
+	{
+		/* We really shouldn't have been polled in these two cases, but
+		   we can handle it. */
+		case CONNECTION_BAD:
+			return PGRES_POLLING_FAILED;
+		case CONNECTION_OK:
+			return PGRES_POLLING_OK;
+
+		/* These are reading states */
+		case CONNECTION_AWAITING_RESPONSE:
+		case CONNECTION_AUTH_RESPONSE:
+		case CONNECTION_ERROR_RESPONSE:
+		case CONNECTION_AUTH_OK:
 		{
-			printfPQExpBuffer(&conn->errorMessage,
-							  "connectDB() -- expected authentication request\n");
-			goto connect_errReturn;
+			/* Load waiting data */
+			int n = pqReadData(conn);
+				
+			if (n < 0)
+				goto error_return;
+			if (n == 0)
+				return PGRES_POLLING_READING;
+
+			break;
 		}
 
-		/* Get the type of request. */
-		if (pqGetInt((int *) &areq, 4, conn))
-			continue;
+		/* These are writing states, so we just proceed. */
+		case CONNECTION_STARTED:
+		case CONNECTION_MADE:
+		   break;
 
-		/* Get the password salt if there is one. */
-		if (areq == AUTH_REQ_CRYPT)
+		case CONNECTION_SETENV:
+			/* We allow PQsetenvPoll to decide whether to proceed */
+			break;
+
+		default:
+			printfPQExpBuffer(&conn->errorMessage,
+							  "PQconnectPoll() -- unknown connection state - "
+							  "probably indicative of memory corruption!\n");
+			goto error_return;
+	}
+
+
+ keep_going: /* We will come back to here until there is nothing left to
+				parse. */
+	switch(conn->status)
+	{
+		case CONNECTION_STARTED:
 		{
-			if (pqGetnchar(conn->salt, sizeof(conn->salt), conn))
-				continue;
+			SOCKET_SIZE_TYPE laddrlen;
+			int optval;
+			socklen_t optlen = sizeof(int);
+
+			/* Write ready, since we've made it here, so the connection
+			 * has been made. */
+
+			/* Now check (using getsockopt) that there is not an error
+			   state waiting for us on the socket. */
+
+			if (getsockopt(conn->sock, SOL_SOCKET, SO_ERROR,
+						   &optval, &optlen) == -1)
+			{
+				printfPQExpBuffer(&conn->errorMessage,
+								  "PQconnectPoll() -- getsockopt() failed: "
+								  "errno=%d\n%s\n",
+								  errno, strerror(errno));
+				goto error_return;
+			}
+			else if (optval != 0)
+			{
+				printfPQExpBuffer(&conn->errorMessage,
+								  "PQconnectPoll() -- "
+								  "socket has error condition %d: %s.\n",
+								  optval, strerror(optval));
+				goto error_return;
+			}
+
+			/* Fill in the client address */
+			laddrlen = sizeof(conn->laddr);
+			if (getsockname(conn->sock, &conn->laddr.sa, &laddrlen) < 0)
+			{
+				printfPQExpBuffer(&conn->errorMessage,
+								  "PQconnectPoll() -- getsockname() failed: "
+								  "errno=%d\n%s\n",
+								  errno, strerror(errno));
+				goto error_return;
+			}
+
+			conn->status = CONNECTION_MADE;
+			return PGRES_POLLING_WRITING;
 		}
 
-		/* OK, we successfully read the message; mark data consumed */
-		conn->inStart = conn->inCursor;
+		case CONNECTION_MADE:
+		{
+			StartupPacket sp;
+			
+			/*
+			 * Initialize the startup packet.
+			 */
 
-		/* Respond to the request if necessary. */
-		/* fe-auth.c has not been fixed to support PQExpBuffers, so: */
-		if (fe_sendauth(areq, conn, conn->pghost, conn->pgpass,
-						conn->errorMessage.data) != STATUS_OK)
+			MemSet((char *) &sp, 0, sizeof(StartupPacket));
+	
+			sp.protoVersion = (ProtocolVersion) htonl(PG_PROTOCOL_LIBPQ);
+			
+			strncpy(sp.user, conn->pguser, SM_USER);
+			strncpy(sp.database, conn->dbName, SM_DATABASE);
+			strncpy(sp.tty, conn->pgtty, SM_TTY);
+
+			if (conn->pgoptions)
+				strncpy(sp.options, conn->pgoptions, SM_OPTIONS);
+
+			/* Send the startup packet. */
+
+			if (pqPacketSend(conn, (char *) &sp,
+							 sizeof(StartupPacket)) != STATUS_OK)
+			{
+				printfPQExpBuffer(&conn->errorMessage,
+								  "PQconnectPoll() --  "
+								  "couldn't send startup packet: "
+								  "errno=%d\n%s\n",
+								  errno, strerror(errno));
+				goto error_return;
+			}
+
+			conn->status = CONNECTION_AWAITING_RESPONSE;
+			return PGRES_POLLING_READING;
+		}
+
+
+		/*
+		 * Handle the authentication exchange: wait for backend messages
+		 * and respond as necessary.
+		 */
+		case CONNECTION_AWAITING_RESPONSE:
+		{
+			char		beresp;
+
+			/* Scan the message */
+			conn->inCursor = conn->inStart;
+
+			if (pqGetc(&beresp, conn))
+			{
+				/* We'll come back when there are more data */
+				return PGRES_POLLING_READING;
+			}
+
+			/* Handle errors. */
+			if (beresp == 'E')
+			{
+				conn->status = CONNECTION_ERROR_RESPONSE;
+				goto keep_going;
+			}
+
+			/* Otherwise it should be an authentication request. */
+			if (beresp != 'R')
+			{
+				printfPQExpBuffer(&conn->errorMessage,
+							   "PQconnectPoll() -- expected authentication "
+							   "request\n");
+				goto error_return;
+			}
+
+			/* Got an authentication request, so that's OK */
+			conn->status = CONNECTION_AUTH_RESPONSE;
+			goto keep_going;
+		}
+
+		case CONNECTION_AUTH_RESPONSE:
 		{
+			AuthRequest areq;
+			
+			/* Get the type of request. */
+			if (pqGetInt((int *) &areq, 4, conn))
+			{
+				/* We'll come back when there are more data */
+				return PGRES_POLLING_READING;
+			}
+
+			/* Get the password salt if there is one. */
+			if (areq == AUTH_REQ_CRYPT)
+			{
+				if (pqGetnchar(conn->salt, sizeof(conn->salt), conn))
+				{
+					/* We'll come back when there are more data */
+					return PGRES_POLLING_READING;
+				}
+			}
+
+			/* OK, we successfully read the message; mark data consumed */
+			conn->inStart = conn->inCursor;
+
+			/* Respond to the request if necessary. */
+			/* Note that conn->pghost must be non-NULL if we are going
+			 * avoid the Kerberos code doing a hostname look-up. */
+			/* XXX fe-auth.c has not been fixed to support PQExpBuffers, so: */
+			if (fe_sendauth(areq, conn, conn->pghost, conn->pgpass,
+							conn->errorMessage.data) != STATUS_OK)
+			{
+				conn->errorMessage.len = strlen(conn->errorMessage.data);
+				goto error_return;
+			}
 			conn->errorMessage.len = strlen(conn->errorMessage.data);
-			goto connect_errReturn;
+
+			/* This function has a section near the end that looks like it
+			 * should block.  I think that it will be OK though, since the
+			 * socket is non-blocking, and thus the data should get out
+			 * as quickly as possible.                                    */
+			if (pqFlush(conn))
+				goto error_return;
+
+			if (areq == AUTH_REQ_OK)
+			{
+				/* We are done with authentication exchange */
+				conn->status = CONNECTION_AUTH_OK;
+				/* Set asyncStatus so that PQsetResult will think that what
+				 * comes back next is the result of a query.  See below.  */
+				conn->asyncStatus = PGASYNC_BUSY;
+				goto keep_going;
+			}
+
+			conn->status = CONNECTION_AWAITING_RESPONSE;
+			return PGRES_POLLING_READING;
 		}
 
-		if (pqFlush(conn))
-			goto connect_errReturn;
+		case CONNECTION_ERROR_RESPONSE:
+			if (pqGets(&conn->errorMessage, conn))
+			{
+				/* We'll come back when there are more data */
+				return PGRES_POLLING_READING;
+			}
+			goto error_return;
 
-		/* Are we done? */
-		if (areq == AUTH_REQ_OK)
-			break;
-	}
+		case CONNECTION_AUTH_OK:
+		{
+			/* ----------
+			 * Now we expect to hear from the backend. A ReadyForQuery
+			 * message indicates that startup is successful, but we might
+			 * also get an Error message indicating failure. (Notice
+			 * messages indicating nonfatal warnings are also allowed by
+			 * the protocol, as is a BackendKeyData message.) Easiest way
+			 * to handle this is to let PQgetResult() read the messages. We
+			 * just have to fake it out about the state of the connection.
+			 *----------
+			 */
 
-	/*
-	 * Now we expect to hear from the backend. A ReadyForQuery message
-	 * indicates that startup is successful, but we might also get an
-	 * Error message indicating failure. (Notice messages indicating
-	 * nonfatal warnings are also allowed by the protocol, as is a
-	 * BackendKeyData message.) Easiest way to handle this is to let
-	 * PQgetResult() read the messages. We just have to fake it out about
-	 * the state of the connection.
-	 */
+			if (!PQconsumeInput(conn))
+				goto error_return;
 
-	conn->status = CONNECTION_OK;
-	conn->asyncStatus = PGASYNC_BUSY;
-	res = PQgetResult(conn);
-	/* NULL return indicating we have gone to IDLE state is expected */
-	if (res)
-	{
-		if (res->resultStatus != PGRES_FATAL_ERROR)
+			if(PQisBusy(conn))
+				return PGRES_POLLING_READING;
+			
+			res = PQgetResult(conn);
+			/* NULL return indicating we have gone to
+			   IDLE state is expected */
+			if (res)
+			{
+				if (res->resultStatus != PGRES_FATAL_ERROR)
+					printfPQExpBuffer(&conn->errorMessage,
+									  "PQconnectPoll() -- unexpected message "
+									  "during startup\n");
+				PQclear(res);
+				goto error_return;
+			}
+
+			/*
+			 * Post-connection housekeeping. Send environment variables
+			 * to server.
+			 */
+
+			if ((conn->setenv_handle = PQsetenvStart(conn)) == NULL)
+				goto error_return;
+
+			conn->status = CONNECTION_SETENV;
+
+			goto keep_going;
+		}
+
+		case CONNECTION_SETENV:
+			/* We pretend that the connection is OK for the duration of
+			   theses queries. */
+			conn->status = CONNECTION_OK;
+
+			switch(PQsetenvPoll(conn->setenv_handle))
+			{
+				case PGRES_POLLING_OK: /* Success */
+					conn->status = CONNECTION_OK;
+					return PGRES_POLLING_OK;
+
+				case PGRES_POLLING_READING: /* Still going */
+					conn->status = CONNECTION_SETENV;
+					return PGRES_POLLING_READING;
+
+				case PGRES_POLLING_WRITING: /* Still going */
+					conn->status = CONNECTION_SETENV;
+					return PGRES_POLLING_WRITING;
+
+				default:
+					conn->status = CONNECTION_SETENV;
+					goto error_return;
+			}
+			/* Unreachable */
+
+		default:
 			printfPQExpBuffer(&conn->errorMessage,
-							  "connectDB() -- unexpected message during startup\n");
-		PQclear(res);
-		goto connect_errReturn;
+							  "PQconnectPoll() -- unknown connection state - "
+							  "probably indicative of memory corruption!\n",
+							  sizeof(conn->errorMessage));
+			goto error_return;
 	}
 
-	/*
-	 * Post-connection housekeeping. Send environment variables to server
+	/* Unreachable */
+
+error_return:
+	/* ----------
+	 * We used to close the socket at this point, but that makes it awkward
+	 * for those above us if they wish to remove this socket from their
+	 * own records (an fd_set for example).  We'll just have this socket
+	 * closed when PQfinish is called (which is compulsory even after an
+	 * error, since the connection structure must be freed).
+	 * ----------
 	 */
+	return PGRES_POLLING_FAILED;
+}
 
-	PQsetenv(conn);
 
-	return CONNECTION_OK;
+/* ----------------
+ *		PQsetenvStart
+ *
+ * Starts the process of passing the values of a standard set of environment
+ * variables to the backend.
+ *
+ * ---------------- */
+PGsetenvHandle
+PQsetenvStart(PGconn *conn)
+{
+	struct pg_setenv_state *handle;
 
-connect_errReturn:
-	if (conn->sock >= 0)
+	if ((handle = malloc(sizeof(struct pg_setenv_state))) == NULL)
 	{
-#ifdef WIN32
-		closesocket(conn->sock);
-#else
-		close(conn->sock);
-#endif
-		conn->sock = -1;
+		printfPQExpBuffer(&conn->errorMessage,
+						  "PQsetenvStart() -- malloc error - %s\n",
+						  strerror(errno));
+		return NULL;
 	}
-	return CONNECTION_BAD;
 
+	handle->conn = conn;
+	handle->res = NULL;
+	handle->eo = EnvironmentOptions;
+
+#ifdef MULTIBYTE
+	handle->state = SETENV_STATE_ENCODINGS_SEND;
+#else
+	handle->state = SETENV_STATE_OPTION_SEND;
+#endif
+	
+	return handle; /* Note that a struct pg_setenv_state * is the same as a
+					  PGsetenvHandle */
 }
 
-void
-PQsetenv(PGconn *conn)
+/* ----------------
+ *		PQsetenvPoll
+ *
+ * Polls the process of passing the values of a standard set of environment
+ * variables to the backend.
+ *
+ * ---------------- */
+PostgresPollingStatusType
+PQsetenvPoll(PGsetenvHandle handle)
 {
-	struct EnvironmentOptions *eo;
-	char		setQuery[100];	/* note length limits in sprintf's below */
-	const char *val;
-	PGresult   *res;
 #ifdef MULTIBYTE
-	char	   *envname = "PGCLIENTENCODING";
+	const char envname[] = "PGCLIENTENCODING";
+#endif
 
-	/* Set env. variable PGCLIENTENCODING if it's not set already */
-	val = getenv(envname);
-	if (!val || *val == '\0')
+	if (!handle || handle->state == SETENV_STATE_FAILED)
+		return PGRES_POLLING_FAILED;
+
+	/* Check whether there are any data for us */
+	switch (handle->state)
 	{
-		const char *encoding = NULL;
-
-		/* query server encoding */
-		res = PQexec(conn, "select getdatabaseencoding()");
-		if (res && PQresultStatus(res) == PGRES_TUPLES_OK)
-			encoding = PQgetvalue(res, 0, 0);
-		if (!encoding)			/* this should not happen */
-			encoding = pg_encoding_to_char(MULTIBYTE);
-		if (encoding)
+		/* These are reading states */
+#ifdef MULTIBYTE
+		case SETENV_STATE_ENCODINGS_WAIT:
+#endif
+		case SETENV_STATE_OPTION_WAIT:
 		{
-			/* set client encoding via environment variable */
-			char	   *envbuf;
+			/* Load waiting data */
+			int n = pqReadData(handle->conn);
+				
+			if (n < 0)
+				goto error_return;
+			if (n == 0)
+				return PGRES_POLLING_READING;
 
-			envbuf = (char *) malloc(strlen(envname) + strlen(encoding) + 2);
-			sprintf(envbuf, "%s=%s", envname, encoding);
-			putenv(envbuf);
+			break;
 		}
-		PQclear(res);
-	}
+
+		/* These are writing states, so we just proceed. */
+#ifdef MULTIBYTE
+		case SETENV_STATE_ENCODINGS_SEND:
 #endif
+		case SETENV_STATE_OPTION_SEND:
+			break;
+		   
+		default:
+			printfPQExpBuffer(&handle->conn->errorMessage,
+							  "PQsetenvPoll() -- unknown state - "
+							  "probably indicative of memory corruption!\n");
+			goto error_return;
+	}
 
-	for (eo = EnvironmentOptions; eo->envName; eo++)
+
+ keep_going: /* We will come back to here until there is nothing left to
+				parse. */
+	switch(handle->state)
 	{
-		if ((val = getenv(eo->envName)))
+
+#ifdef MULTIBYTE
+		case SETENV_STATE_ENCODINGS_SEND:
 		{
-			if (strcasecmp(val, "default") == 0)
-				sprintf(setQuery, "SET %s = %.60s", eo->pgName, val);
-			else
-				sprintf(setQuery, "SET %s = '%.60s'", eo->pgName, val);
+			const char *env;
+			
+			/* query server encoding */
+			env = getenv(envname);
+			if (!env || *env == '\0')
+			{
+				if (!PQsendQuery(handle->conn,
+								 "select getdatabaseencoding()"))
+					goto error_return;
+
+				handle->state = SETENV_STATE_ENCODINGS_WAIT;
+				return PGRES_POLLING_READING;
+			}
+		}
+
+		case SETENV_STATE_ENCODINGS_WAIT:
+		{
+			const char *encoding = 0;
+
+			if (!PQconsumeInput(handle->conn))
+				goto error_return;
+
+			if (PQisBusy(handle->conn))
+				return PGRES_POLLING_READING;
+			
+			handle->res = PQgetResult(handle->conn);
+
+			if (handle->res)
+			{
+				if (PQresultStatus(handle->res) != PGRES_TUPLES_OK)
+				{
+					PQclear(handle->res);
+					goto error_return;
+				}
+
+				encoding = PQgetvalue(handle->res, 0, 0);
+				if (!encoding)			/* this should not happen */
+					encoding = pg_encoding_to_char(MULTIBYTE);
+
+				if (encoding)
+				{
+					/* set client encoding via environment variable */
+					char	   *envbuf;
+
+					envbuf = (char *) malloc(strlen(envname) + strlen(encoding) + 2);
+					sprintf(envbuf, "%s=%s", envname, encoding);
+					putenv(envbuf);
+				}
+				PQclear(handle->res);
+				/* We have to keep going in order to clear up the query */
+				goto keep_going;
+			}
+
+			/* NULL result indicates that the query is finished */
+
+			/* Move on to setting the environment options */
+			handle->state = SETENV_STATE_OPTION_SEND;
+			goto keep_going;
+		}
+#endif
+
+		case SETENV_STATE_OPTION_SEND:
+		{
+			/* Send an Environment Option */
+			char		setQuery[100];	/* note length limits in sprintf's below */
+
+			if (handle->eo->envName)
+			{
+				const char *val;
+
+				if ((val = getenv(handle->eo->envName)))
+				{
+					if (strcasecmp(val, "default") == 0)
+						sprintf(setQuery, "SET %s = %.60s",
+								handle->eo->pgName, val);
+					else
+						sprintf(setQuery, "SET %s = '%.60s'",
+								handle->eo->pgName, val);
 #ifdef CONNECTDEBUG
-			printf("Use environment variable %s to send %s\n", eo->envName, setQuery);
+					printf("Use environment variable %s to send %s\n",
+						   handle->eo->envName, setQuery);
 #endif
-			res = PQexec(conn, setQuery);
-			PQclear(res);		/* Don't care? */
+					if (!PQsendQuery(handle->conn, setQuery))
+						goto error_return;
+
+					handle->state = SETENV_STATE_OPTION_WAIT;
+				}
+				else
+				{
+					handle->eo++;
+				}
+			}
+			else
+			{
+				/* No option to send, so we are done. */
+				handle->state = SETENV_STATE_OK;
+			}
+
+			goto keep_going;
 		}
+
+		case SETENV_STATE_OPTION_WAIT:
+		{
+			if (!PQconsumeInput(handle->conn))
+				goto error_return;
+
+			if (PQisBusy(handle->conn))
+				return PGRES_POLLING_READING;
+			
+			handle->res = PQgetResult(handle->conn);
+
+			if (handle->res)
+			{
+				if (PQresultStatus(handle->res) != PGRES_COMMAND_OK)
+				{
+					PQclear(handle->res);
+					goto error_return;
+				}
+				/* Don't need the result */
+				PQclear(handle->res);
+				/* We have to keep going in order to clear up the query */
+				goto keep_going;
+			}
+
+			/* NULL result indicates that the query is finished */
+
+			/* Send the next option */
+			handle->eo++;
+			handle->state = SETENV_STATE_OPTION_SEND;
+			goto keep_going;
+		}
+
+		case SETENV_STATE_OK:
+			/* Tidy up */
+			free(handle);
+			return PGRES_POLLING_OK;
+
+		default:
+			printfPQExpBuffer(&handle->conn->errorMessage,
+							  "PQsetenvPoll() -- unknown state - "
+							  "probably indicative of memory corruption!\n");
+			goto error_return;
+	}
+
+	/* Unreachable */
+
+ error_return:
+	handle->state = SETENV_STATE_FAILED; /* This may protect us even if we
+										  * are called after the handle
+										  * has been freed.             */
+	free(handle);
+	return PGRES_POLLING_FAILED;
+}
+
+
+/* ----------------
+ *		PQsetenvAbort
+ *
+ * Aborts the process of passing the values of a standard set of environment
+ * variables to the backend.
+ *
+ * ---------------- */
+void
+PQsetenvAbort(PGsetenvHandle handle)
+{
+	/* We should not have been called in the FAILED state, but we can cope by
+	 * not freeing the handle (it has probably been freed by now anyway). */
+	if (handle->state != SETENV_STATE_FAILED)
+	{
+		handle->state = SETENV_STATE_FAILED;
+		free(handle);
 	}
-}	/* PQsetenv() */
+}
+
+
+/* ----------------
+ *		PQsetenv
+ *
+ * Passes the values of a standard set of environment variables to the
+ * backend.
+ *
+ * Returns 1 on success, 0 on failure.
+ *
+ * This function used to return void.  I don't think that there should be
+ * compatibility problems caused by giving it a return value, especially as
+ * this function has not been documented previously.
+ *
+ * ---------------- */
+int
+PQsetenv(PGconn *conn)
+{
+	PostgresPollingStatusType flag;
+	PGsetenvHandle handle;
+	int r = 0, w = 1;
+	
+	if((handle = PQsetenvStart(conn)) == NULL)
+		return 0;
+
+	do
+	{
+		if(pqWait(r, w, conn))
+		{
+			/* XXX This is not a good sign - perhaps we should mark the
+			   connection as bad here... */
+			return 0;
+		}
+
+	again:
+		switch(flag = PQsetenvPoll(handle))
+		{
+			case PGRES_POLLING_ACTIVE:
+				goto again;
+
+			case PGRES_POLLING_OK:
+				break;
+				
+			case PGRES_POLLING_READING:
+				r = 1;
+				w = 0;
+				break;
+				
+			case PGRES_POLLING_WRITING:
+				r = 0;
+				w = 1;
+				break;
+				
+			default: /* Failed */
+				return 0;
+		}
+	} while (flag != PGRES_POLLING_OK);
+  
+	return 1;
+}
+
 
 /*
  * makeEmptyPGconn
@@ -973,6 +1738,8 @@ freePGconn(PGconn *conn)
 #endif
 	if (conn->pghost)
 		free(conn->pghost);
+	if (conn->pghostaddr)
+		free(conn->pghostaddr);
 	if (conn->pgport)
 		free(conn->pgport);
 	if (conn->pgtty)
@@ -1006,6 +1773,12 @@ freePGconn(PGconn *conn)
 static void
 closePGconn(PGconn *conn)
 {
+	if (conn->status == CONNECTION_SETENV)
+	{
+		/* We have to abort the setenv process as well */
+		PQsetenvAbort(conn->setenv_handle);
+	}
+
 	if (conn->sock >= 0)
 	{
 
@@ -1067,8 +1840,47 @@ PQreset(PGconn *conn)
 	if (conn)
 	{
 		closePGconn(conn);
-		conn->status = connectDB(conn);
+
+		(void)(!connectDBStart(conn) || !connectDBComplete(conn));
 	}
+
+	return;
+}
+
+
+/* PQresetStart :
+   resets the connection to the backend
+   closes the existing connection and makes a new one
+   Returns 1 on success, 0 on failure.
+*/
+int
+PQresetStart(PGconn *conn)
+{
+	if (conn)
+	{
+		closePGconn(conn);
+
+		return connectDBStart(conn);
+	}
+
+	return 1;
+}
+
+
+/* PQresetPoll :
+   resets the connection to the backend
+   closes the existing connection and makes a new one
+*/
+
+PostgresPollingStatusType
+PQresetPoll(PGconn *conn)
+{
+	if (conn)
+	{
+		return PQconnectPoll(conn);
+	}
+
+	return PGRES_POLLING_FAILED;
 }