libpq can now talk to either 3.0 or 2.0 protocol servers. It first tries

protocol 3, then falls back to 2 if postmaster rejects the startup packet
with an old-format error message.  A side benefit of the rewrite is that
SSL-encrypted connections can now be made without blocking.  (I think,
anyway, but do not have a good way to test.)

src/backend/libpq/ip.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/libpq/ip.c,v 1.7 2003/04/22 03:52:56 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/libpq/ip.c,v 1.8 2003/06/08 17:42:59 tgl Exp $
  *
  * This file and the IPV6 implementation were initially provided by
  * Nigel Kukard <nkukard@lbsd.net>, Linux Based Systems Design
@@ -72,27 +72,29 @@ getaddrinfo2(const char *hostname, const char *servname,
 
 
 /*
- *	freeaddrinfo2 - free IPv6 addrinfo structures
+ *	freeaddrinfo2 - free addrinfo structures for IPv4, IPv6, or Unix
  */
 void
-freeaddrinfo2(int hint_ai_family, struct addrinfo *ai)
+freeaddrinfo2(struct addrinfo *ai)
 {
-#ifdef HAVE_UNIX_SOCKETS
+	if (ai != NULL)
-	if (hint_ai_family == AF_UNIX)
 	{
-		struct addrinfo *p;
+#ifdef HAVE_UNIX_SOCKETS
-
+		if (ai->ai_family == AF_UNIX)
-		while (ai != NULL)
 		{
-			p = ai;
+			while (ai != NULL)
-			ai = ai->ai_next;
+			{
-			free(p->ai_addr);
+				struct addrinfo *p = ai;
-			free(p);
+
+				ai = ai->ai_next;
+				free(p->ai_addr);
+				free(p);
+			}
 		}
-	}
+		else
-	else
 #endif   /* HAVE_UNIX_SOCKETS */
-		freeaddrinfo(ai);
+			freeaddrinfo(ai);
+	}
 }
 
 

src/backend/libpq/pqcomm.c

@@ -30,7 +30,7 @@
  * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- *	$Header: /cvsroot/pgsql/src/backend/libpq/pqcomm.c,v 1.154 2003/05/29 19:15:34 tgl Exp $
+ *	$Header: /cvsroot/pgsql/src/backend/libpq/pqcomm.c,v 1.155 2003/06/08 17:43:00 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -242,8 +242,7 @@ StreamServerPort(int family, char *hostName, unsigned short portNumber,
 	{
 		elog(LOG, "server socket failure: getaddrinfo2(): %s",
 			 gai_strerror(ret));
-		if (addrs != NULL)
+		freeaddrinfo2(addrs);
-			freeaddrinfo2(hint.ai_family, addrs);
 		return STATUS_ERROR;
 	}
 
@@ -251,7 +250,7 @@ StreamServerPort(int family, char *hostName, unsigned short portNumber,
 	{
 		elog(LOG, "server socket failure: socket(): %s",
 			 strerror(errno));
-		freeaddrinfo2(hint.ai_family, addrs);
+		freeaddrinfo2(addrs);
 		return STATUS_ERROR;
 	}
 
@@ -262,7 +261,7 @@ StreamServerPort(int family, char *hostName, unsigned short portNumber,
 		{
 			elog(LOG, "server socket failure: setsockopt(SO_REUSEADDR): %s",
 				 strerror(errno));
-			freeaddrinfo2(hint.ai_family, addrs);
+			freeaddrinfo2(addrs);
 			return STATUS_ERROR;
 		}
 	}
@@ -279,7 +278,7 @@ StreamServerPort(int family, char *hostName, unsigned short portNumber,
 				 sock_path);
 		else
 			elog(LOG, "\tIf not, wait a few seconds and retry.");
-		freeaddrinfo2(hint.ai_family, addrs);
+		freeaddrinfo2(addrs);
 		return STATUS_ERROR;
 	}
 
@@ -288,7 +287,7 @@ StreamServerPort(int family, char *hostName, unsigned short portNumber,
 	{
 		if (Setup_AF_UNIX() != STATUS_OK)
 		{
-			freeaddrinfo2(hint.ai_family, addrs);
+			freeaddrinfo2(addrs);
 			return STATUS_ERROR;
 		}
 	}
@@ -308,12 +307,12 @@ StreamServerPort(int family, char *hostName, unsigned short portNumber,
 	{
 		elog(LOG, "server socket failure: listen(): %s",
 			 strerror(errno));
-		freeaddrinfo2(hint.ai_family, addrs);
+		freeaddrinfo2(addrs);
 		return STATUS_ERROR;
 	}
 
 	*fdP = fd;
-	freeaddrinfo2(hint.ai_family, addrs);
+	freeaddrinfo2(addrs);
 	return STATUS_OK;
 
 }

src/include/libpq/ip.h

@@ -5,7 +5,7 @@
  *
  * Copyright (c) 2003, PostgreSQL Global Development Group
  *
- * $Id: ip.h,v 1.3 2003/04/02 00:49:28 tgl Exp $
+ * $Id: ip.h,v 1.4 2003/06/08 17:43:00 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -19,7 +19,7 @@
 extern int   getaddrinfo2(const char *hostname, const char *servname,
 						  const struct addrinfo *hintp,
 						  struct addrinfo **result);
-extern void  freeaddrinfo2(int hint_ai_family, struct addrinfo *ai);
+extern void  freeaddrinfo2(struct addrinfo *ai);
 
 extern char *SockAddr_ntop(const SockAddr *sa, char *dst, size_t cnt,
 						   int v4conv);

src/interfaces/libpq/Makefile

@@ -4,7 +4,7 @@
 #
 # Copyright (c) 1994, Regents of the University of California
 #
-# $Header: /cvsroot/pgsql/src/interfaces/libpq/Makefile,v 1.79 2003/05/10 02:05:50 momjian Exp $
+# $Header: /cvsroot/pgsql/src/interfaces/libpq/Makefile,v 1.80 2003/06/08 17:43:00 tgl Exp $
 #
 #-------------------------------------------------------------------------
 
@@ -21,7 +21,7 @@ SO_MINOR_VERSION= 1
 override CPPFLAGS := -I$(srcdir) $(CPPFLAGS) -DFRONTEND -DSYSCONFDIR='"$(sysconfdir)"'
 
 OBJS= fe-auth.o fe-connect.o fe-exec.o fe-misc.o fe-print.o fe-lobj.o \
-      pqexpbuffer.o pqsignal.o fe-secure.o \
+      fe-protocol2.o fe-protocol3.o pqexpbuffer.o pqsignal.o fe-secure.o \
       dllist.o md5.o ip.o wchar.o encnames.o \
       $(filter crypt.o getaddrinfo.o inet_aton.o snprintf.o strerror.o path.o, $(LIBOBJS))
 

src/interfaces/libpq/fe-auth.c

@@ -10,7 +10,7 @@
  * exceed INITIAL_EXPBUFFER_SIZE (currently 256 bytes).
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/interfaces/libpq/fe-auth.c,v 1.78 2003/05/16 04:58:03 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/interfaces/libpq/fe-auth.c,v 1.79 2003/06/08 17:43:00 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -559,7 +559,11 @@ pg_password_sendauth(PGconn *conn, const char *password, AuthRequest areq)
 		default:
 			return STATUS_ERROR;
 	}
-	ret = pqPacketSend(conn, 'p', crypt_pwd, strlen(crypt_pwd) + 1);
+	/* Packet has a message type as of protocol 3.0 */
+	if (PG_PROTOCOL_MAJOR(conn->pversion) >= 3)
+		ret = pqPacketSend(conn, 'p', crypt_pwd, strlen(crypt_pwd) + 1);
+	else
+		ret = pqPacketSend(conn, 0, crypt_pwd, strlen(crypt_pwd) + 1);
 	if (areq == AUTH_REQ_MD5)
 		free(crypt_pwd);
 	return ret;

src/interfaces/libpq/fe-misc.c

@@ -23,7 +23,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/interfaces/libpq/fe-misc.c,v 1.91 2003/04/25 01:24:00 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/interfaces/libpq/fe-misc.c,v 1.92 2003/06/08 17:43:00 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -58,8 +58,6 @@
 #include "pqsignal.h"
 #include "mb/pg_wchar.h"
 
-#define DONOTICE(conn,message) \
-	((*(conn)->noticeHook) ((conn)->noticeArg, (message)))
 
 static int	pqPutMsgBytes(const void *buf, size_t len, PGconn *conn);
 static int	pqSendSome(PGconn *conn, int len);
@@ -227,7 +225,7 @@ pqGetInt(int *result, size_t bytes, PGconn *conn)
 			snprintf(noticeBuf, sizeof(noticeBuf),
 					 libpq_gettext("integer of size %lu not supported by pqGetInt\n"),
 					 (unsigned long) bytes);
-			DONOTICE(conn, noticeBuf);
+			PGDONOTICE(conn, noticeBuf);
 			return EOF;
 	}
 
@@ -265,7 +263,7 @@ pqPutInt(int value, size_t bytes, PGconn *conn)
 			snprintf(noticeBuf, sizeof(noticeBuf),
 					 libpq_gettext("integer of size %lu not supported by pqPutInt\n"),
 					 (unsigned long) bytes);
-			DONOTICE(conn, noticeBuf);
+			PGDONOTICE(conn, noticeBuf);
 			return EOF;
 	}
 
@@ -401,38 +399,57 @@ pqCheckInBufferSpace(int bytes_needed, PGconn *conn)
  * msg_type is the message type byte, or 0 for a message without type byte
  * (only startup messages have no type byte)
  *
+ * force_len forces the message to have a length word; otherwise, we add
+ * a length word if protocol 3.
+ *
  * Returns 0 on success, EOF on error
  *
  * The idea here is that we construct the message in conn->outBuffer,
  * beginning just past any data already in outBuffer (ie, at
  * outBuffer+outCount).  We enlarge the buffer as needed to hold the message.
- * When the message is complete, we fill in the length word and then advance
+ * When the message is complete, we fill in the length word (if needed) and
- * outCount past the message, making it eligible to send.  The state
+ * then advance outCount past the message, making it eligible to send.
- * variable conn->outMsgStart points to the incomplete message's length word
+ *
- * (it is either outCount or outCount+1 depending on whether there is a
+ * The state variable conn->outMsgStart points to the incomplete message's
- * type byte).  The state variable conn->outMsgEnd is the end of the data
+ * length word: it is either outCount or outCount+1 depending on whether
- * collected so far.
+ * there is a type byte.  If we are sending a message without length word
+ * (pre protocol 3.0 only), then outMsgStart is -1.  The state variable
+ * conn->outMsgEnd is the end of the data collected so far.
  */
 int
-pqPutMsgStart(char msg_type, PGconn *conn)
+pqPutMsgStart(char msg_type, bool force_len, PGconn *conn)
 {
 	int			lenPos;
+	int			endPos;
 
-	/* where the message length word will go */
+	/* allow room for message type byte */
 	if (msg_type)
-		lenPos = conn->outCount + 1;
+		endPos = conn->outCount + 1;
 	else
-		lenPos = conn->outCount;
+		endPos = conn->outCount;
-	/* make sure there is room for it */
+
-	if (pqCheckOutBufferSpace(lenPos + 4, conn))
+	/* do we want a length word? */
+	if (force_len || PG_PROTOCOL_MAJOR(conn->pversion) >= 3)
+	{
+		lenPos = endPos;
+		/* allow room for message length */
+		endPos += 4;
+	}
+	else
+	{
+		lenPos = -1;
+	}
+
+	/* make sure there is room for message header */
+	if (pqCheckOutBufferSpace(endPos, conn))
 		return EOF;
 	/* okay, save the message type byte if any */
 	if (msg_type)
 		conn->outBuffer[conn->outCount] = msg_type;
 	/* set up the message pointers */
 	conn->outMsgStart = lenPos;
-	conn->outMsgEnd = lenPos + 4;
+	conn->outMsgEnd = endPos;
-	/* length word will be filled in by pqPutMsgEnd */
+	/* length word, if needed, will be filled in by pqPutMsgEnd */
 
 	if (conn->Pfdebug)
 		fprintf(conn->Pfdebug, "To backend> Msg %c\n",
@@ -472,14 +489,20 @@ pqPutMsgBytes(const void *buf, size_t len, PGconn *conn)
 int
 pqPutMsgEnd(PGconn *conn)
 {
-	uint32		msgLen = conn->outMsgEnd - conn->outMsgStart;
-
 	if (conn->Pfdebug)
 		fprintf(conn->Pfdebug, "To backend> Msg complete, length %u\n",
-				msgLen);
+				conn->outMsgEnd - conn->outCount);
 
-	msgLen = htonl(msgLen);
+	/* Fill in length word if needed */
-	memcpy(conn->outBuffer + conn->outMsgStart, &msgLen, 4);
+	if (conn->outMsgStart >= 0)
+	{
+		uint32		msgLen = conn->outMsgEnd - conn->outMsgStart;
+
+		msgLen = htonl(msgLen);
+		memcpy(conn->outBuffer + conn->outMsgStart, &msgLen, 4);
+	}
+
+	/* Make message eligible to send */
 	conn->outCount = conn->outMsgEnd;
 
 	if (conn->outCount >= 8192)

src/interfaces/libpq/fe-secure.c

@@ -11,7 +11,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/interfaces/libpq/fe-secure.c,v 1.22 2003/04/10 23:03:08 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/interfaces/libpq/fe-secure.c,v 1.23 2003/06/08 17:43:00 tgl Exp $
  *
  * NOTES
  *	  The client *requires* a valid server certificate.  Since
@@ -132,7 +132,7 @@ static DH  *tmp_dh_cb(SSL *s, int is_export, int keylength);
 static int	client_cert_cb(SSL *, X509 **, EVP_PKEY **);
 static int	initialize_SSL(PGconn *);
 static void destroy_SSL(void);
-static int	open_client_SSL(PGconn *);
+static PostgresPollingStatusType open_client_SSL(PGconn *);
 static void close_SSL(PGconn *);
 static const char *SSLerrmessage(void);
 #endif
@@ -231,16 +231,30 @@ pqsecure_destroy(void)
 /*
  *	Attempt to negotiate secure session.
  */
-int
+PostgresPollingStatusType
 pqsecure_open_client(PGconn *conn)
 {
-	int			r = 0;
-
 #ifdef USE_SSL
-	r = open_client_SSL(conn);
+	/* First time through? */
+	if (conn->ssl == NULL)
+	{
+		if (!(conn->ssl = SSL_new(SSL_context)) ||
+			!SSL_set_app_data(conn->ssl, conn) ||
+			!SSL_set_fd(conn->ssl, conn->sock))
+		{
+			printfPQExpBuffer(&conn->errorMessage,
+			   libpq_gettext("could not establish SSL connection: %s\n"),
+							  SSLerrmessage());
+			close_SSL(conn);
+			return PGRES_POLLING_FAILED;
+		}
+	}
+	/* Begin or continue the actual handshake */
+	return open_client_SSL(conn);
+#else
+	/* shouldn't get here */
+	return PGRES_POLLING_FAILED;
 #endif
-
-	return r;
 }
 
 /*
@@ -273,8 +287,15 @@ pqsecure_read(PGconn *conn, void *ptr, size_t len)
 			case SSL_ERROR_NONE:
 				break;
 			case SSL_ERROR_WANT_READ:
+				n = 0;
+				break;
 			case SSL_ERROR_WANT_WRITE:
-				/* XXX to support nonblock I/O, we should return 0 here */
+				/*
+				 * Returning 0 here would cause caller to wait for read-ready,
+				 * which is not correct since what SSL wants is wait for
+				 * write-ready.  The former could get us stuck in an infinite
+				 * wait, so don't risk it; busy-loop instead.
+				 */
 				goto rloop;
 			case SSL_ERROR_SYSCALL:
 				if (n == -1)
@@ -322,16 +343,22 @@ pqsecure_write(PGconn *conn, const void *ptr, size_t len)
 #ifdef USE_SSL
 	if (conn->ssl)
 	{
-	wloop:
 		n = SSL_write(conn->ssl, ptr, len);
 		switch (SSL_get_error(conn->ssl, n))
 		{
 			case SSL_ERROR_NONE:
 				break;
 			case SSL_ERROR_WANT_READ:
+				/*
+				 * Returning 0 here causes caller to wait for write-ready,
+				 * which is not really the right thing, but it's the best
+				 * we can do.
+				 */
+				n = 0;
+				break;
 			case SSL_ERROR_WANT_WRITE:
-				/* XXX to support nonblock I/O, we should return 0 here */
+				n = 0;
-				goto wloop;
+				break;
 			case SSL_ERROR_SYSCALL:
 				if (n == -1)
 					printfPQExpBuffer(&conn->errorMessage,
@@ -802,23 +829,45 @@ destroy_SSL(void)
 /*
  *	Attempt to negotiate SSL connection.
  */
-static int
+static PostgresPollingStatusType
 open_client_SSL(PGconn *conn)
 {
-#ifdef NOT_USED
 	int			r;
-#endif
 
-	if (!(conn->ssl = SSL_new(SSL_context)) ||
+	r = SSL_connect(conn->ssl);
-		!SSL_set_app_data(conn->ssl, conn) ||
+	if (r <= 0)
-		!SSL_set_fd(conn->ssl, conn->sock) ||
-		SSL_connect(conn->ssl) <= 0)
 	{
-		printfPQExpBuffer(&conn->errorMessage,
+		switch (SSL_get_error(conn->ssl, r))
-			   libpq_gettext("could not establish SSL connection: %s\n"),
+		{
-						  SSLerrmessage());
+			case SSL_ERROR_WANT_READ:
-		close_SSL(conn);
+				return PGRES_POLLING_READING;
-		return -1;
+				
+			case SSL_ERROR_WANT_WRITE:
+				return PGRES_POLLING_WRITING;
+
+			case SSL_ERROR_SYSCALL:
+				if (r == -1)
+					printfPQExpBuffer(&conn->errorMessage,
+								libpq_gettext("SSL SYSCALL error: %s\n"),
+								  SOCK_STRERROR(SOCK_ERRNO));
+				else
+					printfPQExpBuffer(&conn->errorMessage,
+								libpq_gettext("SSL SYSCALL error: EOF detected\n"));
+				close_SSL(conn);
+				return PGRES_POLLING_FAILED;
+
+			case SSL_ERROR_SSL:
+				printfPQExpBuffer(&conn->errorMessage,
+					  libpq_gettext("SSL error: %s\n"), SSLerrmessage());
+				close_SSL(conn);
+				return PGRES_POLLING_FAILED;
+
+			default:
+				printfPQExpBuffer(&conn->errorMessage,
+								  libpq_gettext("Unknown SSL error code\n"));
+				close_SSL(conn);
+				return PGRES_POLLING_FAILED;
+		}
 	}
 
 	/* check the certificate chain of the server */
@@ -836,7 +885,7 @@ open_client_SSL(PGconn *conn)
 			   libpq_gettext("certificate could not be validated: %s\n"),
 						  X509_verify_cert_error_string(r));
 		close_SSL(conn);
-		return -1;
+		return PGRES_POLLING_FAILED;
 	}
 #endif
 
@@ -848,7 +897,7 @@ open_client_SSL(PGconn *conn)
 				libpq_gettext("certificate could not be obtained: %s\n"),
 						  SSLerrmessage());
 		close_SSL(conn);
-		return -1;
+		return PGRES_POLLING_FAILED;
 	}
 
 	X509_NAME_oneline(X509_get_subject_name(conn->peer),
@@ -871,11 +920,12 @@ open_client_SSL(PGconn *conn)
 	if (verify_peer(conn) == -1)
 	{
 		close_SSL(conn);
-		return -1;
+		return PGRES_POLLING_FAILED;
 	}
 #endif
 
-	return 0;
+	/* SSL handshake is complete */
+	return PGRES_POLLING_OK;
 }
 
 /*

src/interfaces/libpq/libpq-fe.h

@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: libpq-fe.h,v 1.92 2003/04/19 00:02:30 tgl Exp $
+ * $Id: libpq-fe.h,v 1.93 2003/06/08 17:43:00 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -38,9 +38,9 @@ extern		"C"
 typedef enum
 {
 	/*
-	 * Although you may decide to change this list in some way, values
+	 * Although it is okay to add to this list, values which become unused
-	 * which become unused should never be removed, nor should constants
+	 * should never be removed, nor should constants be redefined - that would
-	 * be redefined - that would break compatibility with existing code.
+	 * break compatibility with existing code.
 	 */
 	CONNECTION_OK,
 	CONNECTION_BAD,
@@ -56,7 +56,9 @@ typedef enum
 										 * postmaster.		  */
 	CONNECTION_AUTH_OK,			/* Received authentication; waiting for
 								 * backend startup. */
-	CONNECTION_SETENV			/* Negotiating environment.    */
+	CONNECTION_SETENV,			/* Negotiating environment. */
+	CONNECTION_SSL_STARTUP,		/* Negotiating SSL. */
+	CONNECTION_NEEDED			/* Internal state: connect() needed */
 } ConnStatusType;
 
 typedef enum
@@ -71,7 +73,7 @@ typedef enum
 
 typedef enum
 {
-	PGRES_EMPTY_QUERY = 0,
+	PGRES_EMPTY_QUERY = 0,		/* empty query string was executed */
 	PGRES_COMMAND_OK,			/* a query command that doesn't return
 								 * anything was executed properly by the
 								 * backend */
@@ -82,8 +84,8 @@ typedef enum
 	PGRES_COPY_IN,				/* Copy In data transfer in progress */
 	PGRES_BAD_RESPONSE,			/* an unexpected response was recv'd from
 								 * the backend */
-	PGRES_NONFATAL_ERROR,
+	PGRES_NONFATAL_ERROR,		/* notice or warning message */
-	PGRES_FATAL_ERROR
+	PGRES_FATAL_ERROR			/* query failed */
 } ExecStatusType;
 
 /* PGconn encapsulates a connection to the backend.

src/interfaces/libpq/libpq-int.h

@@ -12,7 +12,7 @@
  * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: libpq-int.h,v 1.70 2003/05/08 18:33:39 tgl Exp $
+ * $Id: libpq-int.h,v 1.71 2003/06/08 17:43:00 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -35,6 +35,7 @@ typedef int ssize_t;			/* ssize_t doesn't exist in VC (atleast
 #include "postgres_fe.h"
 
 /* include stuff common to fe and be */
+#include "getaddrinfo.h"
 #include "libpq/pqcomm.h"
 #include "lib/dllist.h"
 /* include stuff found in fe only */
@@ -45,23 +46,9 @@ typedef int ssize_t;			/* ssize_t doesn't exist in VC (atleast
 #include <openssl/err.h>
 #endif
 
-/* libpq supports this version of the frontend/backend protocol.
- *
- * NB: we used to use PG_PROTOCOL_LATEST from the backend pqcomm.h file,
- * but that's not really the right thing: just recompiling libpq
- * against a more recent backend isn't going to magically update it
- * for most sorts of protocol changes.	So, when you change libpq
- * to support a different protocol revision, you have to change this
- * constant too.  PG_PROTOCOL_EARLIEST and PG_PROTOCOL_LATEST in
- * pqcomm.h describe what the backend knows, not what libpq knows.
- */
-
-#define PG_PROTOCOL_LIBPQ	PG_PROTOCOL(3,0)
-
 /*
  * POSTGRES backend dependent Constants.
  */
-
 #define PQERRORMSG_LENGTH 1024
 #define CMDSTATUS_LEN 40
 
@@ -96,20 +83,22 @@ typedef struct pgresAttDesc
 	int			atttypmod;		/* type-specific modifier info */
 }	PGresAttDesc;
 
-/* Data for a single attribute of a single tuple */
+/*
-
+ * Data for a single attribute of a single tuple
-/* We use char* for Attribute values.
+ *
-   The value pointer always points to a null-terminated area; we add a
+ * We use char* for Attribute values.
-   null (zero) byte after whatever the backend sends us.  This is only
+ *
-   particularly useful for text tuples ... with a binary value, the
+ * The value pointer always points to a null-terminated area; we add a
-   value might have embedded nulls, so the application can't use C string
+ * null (zero) byte after whatever the backend sends us.  This is only
-   operators on it.  But we add a null anyway for consistency.
+ * particularly useful for text tuples ... with a binary value, the
-   Note that the value itself does not contain a length word.
+ * value might have embedded nulls, so the application can't use C string
-
+ * operators on it.  But we add a null anyway for consistency.
-   A NULL attribute is a special case in two ways: its len field is NULL_LEN
+ * Note that the value itself does not contain a length word.
-   and its value field points to null_field in the owning PGresult.  All the
+ *
-   NULL attributes in a query result point to the same place (there's no need
+ * A NULL attribute is a special case in two ways: its len field is NULL_LEN
-   to store a null string separately for each one).
+ * and its value field points to null_field in the owning PGresult.  All the
+ * NULL attributes in a query result point to the same place (there's no need
+ * to store a null string separately for each one).
  */
 
 #define NULL_LEN		(-1)	/* pg_result len for NULL value */
@@ -135,15 +124,6 @@ struct pg_result
 	int			binary;			/* binary tuple values if binary == 1,
 								 * otherwise text */
 
-	/*
-	 * The conn link in PGresult is no longer used by any libpq code. It
-	 * should be removed entirely, because it could be a dangling link
-	 * (the application could keep the PGresult around longer than it
-	 * keeps the PGconn!)  But there may be apps out there that depend on
-	 * it, so we will leave it here at least for a release or so.
-	 */
-	PGconn	   *xconn;			/* connection we did the query on, if any */
-
 	/*
 	 * These fields are copied from the originating PGconn, so that
 	 * operations on the PGresult don't have to reference the PGconn.
@@ -194,6 +174,35 @@ typedef enum
 	PGASYNC_COPY_OUT			/* Copy Out data transfer in progress */
 }	PGAsyncStatusType;
 
+/* PGSetenvStatusType defines the state of the PQSetenv state machine */
+/* (this is used only for 2.0-protocol connections) */
+typedef enum
+{
+	SETENV_STATE_OPTION_SEND,	/* About to send an Environment Option */
+	SETENV_STATE_OPTION_WAIT,	/* Waiting for above send to complete */
+	SETENV_STATE_QUERY1_SEND,	/* About to send a status query */
+	SETENV_STATE_QUERY1_WAIT,	/* Waiting for query to complete */
+	SETENV_STATE_QUERY2_SEND,	/* About to send a status query */
+	SETENV_STATE_QUERY2_WAIT,	/* Waiting for query to complete */
+	SETENV_STATE_IDLE
+}	PGSetenvStatusType;
+
+/* Typedef for the EnvironmentOptions[] array */
+typedef struct PQEnvironmentOption
+{
+	const char *envName,		/* name of an environment variable */
+			   *pgName;			/* name of corresponding SET variable */
+} PQEnvironmentOption;
+
+/* Typedef for parameter-status list entries */
+typedef struct pgParameterStatus
+{
+	struct pgParameterStatus *next;	/* list link */
+	char	   *name;			/* parameter name */
+	char	   *value;			/* parameter value */
+	/* Note: name and value are stored in same malloc block as struct is */
+} pgParameterStatus;
+
 /* large-object-access data ... allocated only if large-object code is used. */
 typedef struct pgLobjfuncs
 {
@@ -207,7 +216,8 @@ typedef struct pgLobjfuncs
 	Oid			fn_lo_write;	/* OID of backend function LOwrite		*/
 }	PGlobjfuncs;
 
-/* PGconn stores all the state data associated with a single connection
+/*
+ * PGconn stores all the state data associated with a single connection
  * to a backend.
  */
 struct pg_conn
@@ -254,12 +264,21 @@ struct pg_conn
 	SockAddr	laddr;			/* Local address */
 	SockAddr	raddr;			/* Remote address */
 	int			raddr_len;		/* Length of remote address */
+	ProtocolVersion pversion;	/* FE/BE protocol version in use */
+	char		sversion[8];	/* The first few bytes of server version */
+
+	/* Transient state needed while establishing connection */
+	struct addrinfo *addrlist;	/* list of possible backend addresses */
+	struct addrinfo *addr_cur;	/* the one currently being tried */
+	PGSetenvStatusType setenv_state; /* for 2.0 protocol only */
+	const PQEnvironmentOption *next_eo;
 
 	/* Miscellaneous stuff */
 	int			be_pid;			/* PID of backend --- needed for cancels */
 	int			be_key;			/* key of backend --- needed for cancels */
 	char		md5Salt[4];		/* password salt received from backend */
 	char		cryptSalt[2];	/* password salt received from backend */
+	pgParameterStatus *pstatus;	/* ParameterStatus data */
 	int			client_encoding; /* encoding id */
 	PGlobjfuncs *lobjfuncs;		/* private state for large-object access
 								 * fns */
@@ -279,7 +298,8 @@ struct pg_conn
 	int			outCount;		/* number of chars waiting in buffer */
 
 	/* State for constructing messages in outBuffer */
-	int			outMsgStart;	/* offset to msg start (length word) */
+	int			outMsgStart;	/* offset to msg start (length word);
+								 * if -1, msg has no length word */
 	int			outMsgEnd;		/* offset to msg end (so far) */
 
 	/* Status for asynchronous result construction */
@@ -324,10 +344,46 @@ extern int	pqPacketSend(PGconn *conn, char pack_type,
 /* === in fe-exec.c === */
 
 extern void pqSetResultError(PGresult *res, const char *msg);
+extern void pqCatenateResultError(PGresult *res, const char *msg);
 extern void *pqResultAlloc(PGresult *res, size_t nBytes, bool isBinary);
 extern char *pqResultStrdup(PGresult *res, const char *str);
 extern void pqClearAsyncResult(PGconn *conn);
-extern int	pqGetErrorNotice(PGconn *conn, bool isError);
+extern void pqSaveErrorResult(PGconn *conn);
+extern PGresult *pqPrepareAsyncResult(PGconn *conn);
+extern int	pqAddTuple(PGresult *res, PGresAttValue *tup);
+extern void pqSaveParameterStatus(PGconn *conn, const char *name,
+								  const char *value);
+extern const char *pqGetParameterStatus(PGconn *conn, const char *name);
+extern void pqHandleSendFailure(PGconn *conn);
+
+/* === in fe-protocol2.c === */
+
+extern PostgresPollingStatusType pqSetenvPoll(PGconn *conn);
+
+extern char *pqBuildStartupPacket2(PGconn *conn, int *packetlen,
+								   const PQEnvironmentOption *options);
+extern void pqParseInput2(PGconn *conn);
+extern int	pqGetline2(PGconn *conn, char *s, int maxlen);
+extern int	pqGetlineAsync2(PGconn *conn, char *buffer, int bufsize);
+extern int	pqEndcopy2(PGconn *conn);
+extern PGresult *pqFunctionCall2(PGconn *conn, Oid fnid,
+								 int *result_buf, int *actual_result_len,
+								 int result_is_int,
+								 const PQArgBlock *args, int nargs);
+
+/* === in fe-protocol3.c === */
+
+extern char *pqBuildStartupPacket3(PGconn *conn, int *packetlen,
+								   const PQEnvironmentOption *options);
+extern void pqParseInput3(PGconn *conn);
+extern int	pqGetErrorNotice3(PGconn *conn, bool isError);
+extern int	pqGetline3(PGconn *conn, char *s, int maxlen);
+extern int	pqGetlineAsync3(PGconn *conn, char *buffer, int bufsize);
+extern int	pqEndcopy3(PGconn *conn);
+extern PGresult *pqFunctionCall3(PGconn *conn, Oid fnid,
+								 int *result_buf, int *actual_result_len,
+								 int result_is_int,
+								 const PQArgBlock *args, int nargs);
 
 /* === in fe-misc.c === */
 
@@ -345,7 +401,7 @@ extern int	pqGetnchar(char *s, size_t len, PGconn *conn);
 extern int	pqPutnchar(const char *s, size_t len, PGconn *conn);
 extern int	pqGetInt(int *result, size_t bytes, PGconn *conn);
 extern int	pqPutInt(int value, size_t bytes, PGconn *conn);
-extern int	pqPutMsgStart(char msg_type, PGconn *conn);
+extern int	pqPutMsgStart(char msg_type, bool force_len, PGconn *conn);
 extern int	pqPutMsgEnd(PGconn *conn);
 extern int	pqReadData(PGconn *conn);
 extern int	pqFlush(PGconn *conn);
@@ -359,21 +415,14 @@ extern int	pqWriteReady(PGconn *conn);
 
 extern int	pqsecure_initialize(PGconn *);
 extern void pqsecure_destroy(void);
-extern int	pqsecure_open_client(PGconn *);
+extern PostgresPollingStatusType pqsecure_open_client(PGconn *);
 extern void pqsecure_close(PGconn *);
 extern ssize_t pqsecure_read(PGconn *, void *ptr, size_t len);
 extern ssize_t pqsecure_write(PGconn *, const void *ptr, size_t len);
 
-/* bits in a byte */
+/* Note: PGDONOTICE macro will work if applied to either PGconn or PGresult */
-#define BYTELEN 8
+#define PGDONOTICE(conn,message) \
-
+	((*(conn)->noticeHook) ((conn)->noticeArg, (message)))
-/* fall back options if they are not specified by arguments or defined
-   by environment variables */
-#define DefaultHost		"localhost"
-#define DefaultTty		""
-#define DefaultOption	""
-#define DefaultAuthtype		  ""
-#define DefaultPassword		  ""
 
 /*
  * this is so that we can check is a connection is non-blocking internally