Replication connection URI?

>From 44d9d6a2c9cf5af83988f9d3b6eeb39c36104ef9 Mon Sep 17 00:00:00 2001
From: Alex Shulgin <ash@commandprompt.com>
Date: Mon, 24 Nov 2014 18:12:51 +0300
Subject: [PATCH 2/3] Allow further dbname=value to override conninfo parsed
 from an expanded dbname in conninfo_array_parse().

---
 src/interfaces/libpq/fe-connect.c | 18 +++++++++++++-----
 1 file changed, 13 insertions(+), 5 deletions(-)

diff --git a/src/interfaces/libpq/fe-connect.c b/src/interfaces/libpq/fe-connect.c
new file mode 100644
index d7f2ec2..5b45128
*** a/src/interfaces/libpq/fe-connect.c
--- b/src/interfaces/libpq/fe-connect.c
*************** conninfo_parse(const char *conninfo, PQE
*** 4302,4311 ****
   * Defaults are supplied (from a service file, environment variables, etc)
   * for unspecified options, but only if use_defaults is TRUE.
   *
!  * If expand_dbname is non-zero, and the value passed for keyword "dbname" is a
!  * connection string (as indicated by recognized_connection_string) then parse
!  * and process it, overriding any previously processed conflicting
!  * keywords. Subsequent keywords will take precedence, however.
   */
  static PQconninfoOption *
  conninfo_array_parse(const char *const * keywords, const char *const * values,
--- 4302,4313 ----
   * Defaults are supplied (from a service file, environment variables, etc)
   * for unspecified options, but only if use_defaults is TRUE.
   *
!  * If expand_dbname is non-zero, and the value passed for the first occurrence
!  * of "dbname" keyword is a connection string (as indicated by
!  * recognized_connection_string) then parse and process it, overriding any
!  * previously processed conflicting keywords. Subsequent keywords will take
!  * precedence, however. In particular, a further occurrence of "dbname" may
!  * override the dbname provided in the connection string.
   */
  static PQconninfoOption *
  conninfo_array_parse(const char *const * keywords, const char *const * values,
*************** conninfo_array_parse(const char *const *
*** 4381,4387 ****
  			}
  
  			/*
! 			 * If we are on the dbname parameter, and we have a parsed
  			 * connection string, copy those parameters across, overriding any
  			 * existing previous settings.
  			 */
--- 4383,4389 ----
  			}
  
  			/*
! 			 * If we are on the *first* dbname parameter, and we have a parsed
  			 * connection string, copy those parameters across, overriding any
  			 * existing previous settings.
  			 */
*************** conninfo_array_parse(const char *const *
*** 4415,4420 ****
--- 4417,4428 ----
  						}
  					}
  				}
+ 				/*
+ 				 * Clear out the parsed dbname, so that a possible further
+ 				 * occurrence of dbname have the chance to override it.
+ 				 */
+ 				PQconninfoFree(dbname_options);
+ 				dbname_options = NULL;
  			}
  			else
  			{
-- 
2.1.0

>From 69e7c676e3af6f25520990cfb4337fc129741a95 Mon Sep 17 00:00:00 2001
From: Alex Shulgin <ash@commandprompt.com>
Date: Mon, 24 Nov 2014 18:54:01 +0300
Subject: [PATCH 3/3] Allow URI in primary_conninfo line of recovery.conf file.

---
 doc/src/sgml/high-availability.sgml                      |  6 +++---
 doc/src/sgml/recovery-config.sgml                        |  4 ++--
 src/backend/access/transam/recovery.conf.sample          |  3 ++-
 .../replication/libpqwalreceiver/libpqwalreceiver.c      | 16 +++++++---------
 4 files changed, 14 insertions(+), 15 deletions(-)

diff --git a/doc/src/sgml/high-availability.sgml b/doc/src/sgml/high-availability.sgml
new file mode 100644
index d249959..61cf585
*** a/doc/src/sgml/high-availability.sgml
--- b/doc/src/sgml/high-availability.sgml
*************** protocol to make nodes agree on a serial
*** 681,689 ****
  
     <para>
       If you want to use streaming replication, fill in
!      <varname>primary_conninfo</> with a libpq connection string, including
!      the host name (or IP address) and any additional details needed to
!      connect to the primary server. If the primary needs a password for
       authentication, the password needs to be specified in
       <varname>primary_conninfo</> as well.
     </para>
--- 681,689 ----
  
     <para>
       If you want to use streaming replication, fill in
!      <varname>primary_conninfo</> with a libpq connection string or a URI,
!      including the host name (or IP address) and any additional details needed
!      to connect to the primary server. If the primary needs a password for
       authentication, the password needs to be specified in
       <varname>primary_conninfo</> as well.
     </para>
diff --git a/doc/src/sgml/recovery-config.sgml b/doc/src/sgml/recovery-config.sgml
new file mode 100644
index 0f1ff34..9e17e20
*** a/doc/src/sgml/recovery-config.sgml
--- b/doc/src/sgml/recovery-config.sgml
*************** restore_command = 'copy "C:\\server\\arc
*** 342,349 ****
          </term>
          <listitem>
           <para>
!           Specifies a connection string to be used for the standby server
!           to connect with the primary. This string is in the format
            described in <xref linkend="libpq-connstring">. If any option is
            unspecified in this string, then the corresponding environment
            variable (see <xref linkend="libpq-envars">) is checked. If the
--- 342,349 ----
          </term>
          <listitem>
           <para>
!           Specifies a connection string or a URI to be used for the standby
!           server to connect with the primary. This string is in the format
            described in <xref linkend="libpq-connstring">. If any option is
            unspecified in this string, then the corresponding environment
            variable (see <xref linkend="libpq-envars">) is checked. If the
diff --git a/src/backend/access/transam/recovery.conf.sample b/src/backend/access/transam/recovery.conf.sample
new file mode 100644
index 7657df3..b1815be
*** a/src/backend/access/transam/recovery.conf.sample
--- b/src/backend/access/transam/recovery.conf.sample
***************
*** 116,124 ****
  # primary_conninfo
  #
  # If set, the PostgreSQL server will try to connect to the primary using this
! # connection string and receive XLOG records continuously.
  #
  #primary_conninfo = ''		# e.g. 'host=localhost port=5432'
  #
  # If set, the PostgreSQL server will use the specified replication slot when
  # connecting to the primary via streaming replication to control resource
--- 116,125 ----
  # primary_conninfo
  #
  # If set, the PostgreSQL server will try to connect to the primary using this
! # connection string or URI and receive XLOG records continuously.
  #
  #primary_conninfo = ''		# e.g. 'host=localhost port=5432'
+ 				# or 'postgres://localhost:5432/'
  #
  # If set, the PostgreSQL server will use the specified replication slot when
  # connecting to the primary via streaming replication to control resource
diff --git a/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c b/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c
new file mode 100644
index 65e95c5..eebb3bb
*** a/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c
--- b/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c
*************** _PG_init(void)
*** 89,106 ****
  static void
  libpqrcv_connect(char *conninfo)
  {
! 	char		conninfo_repl[MAXCONNINFO + 75];
  
  	/*
! 	 * Connect using deliberately undocumented parameter: replication. The
! 	 * database name is ignored by the server in replication mode, but specify
! 	 * "replication" for .pgpass lookup.
  	 */
! 	snprintf(conninfo_repl, sizeof(conninfo_repl),
! 			 "%s dbname=replication replication=true fallback_application_name=walreceiver",
! 			 conninfo);
! 
! 	streamConn = PQconnectdb(conninfo_repl);
  	if (PQstatus(streamConn) != CONNECTION_OK)
  		ereport(ERROR,
  				(errmsg("could not connect to the primary server: %s",
--- 89,104 ----
  static void
  libpqrcv_connect(char *conninfo)
  {
! 	const char	*keys[] = { "dbname", "dbname",      "replication", "fallback_application_name", NULL };
! 	const char	*vals[] = { conninfo, "replication", "true",        "walreceiver",               NULL };
  
  	/*
! 	 * We exploit the expand_dbname parameter to process the connection string
! 	 * (or URI), then override the options that are necessary to establish the
! 	 * replication type of connection.  In particular, we override any
! 	 * database name provided in conninfo with "replication".
  	 */
! 	streamConn = PQconnectdbParams(keys, vals, /* expand_dbname = */ true);
  	if (PQstatus(streamConn) != CONNECTION_OK)
  		ereport(ERROR,
  				(errmsg("could not connect to the primary server: %s",
-- 
2.1.0

>From 156e6faa96ad6a2ce58055ad72883ed78c576e5b Mon Sep 17 00:00:00 2001
From: Alex Shulgin <ash@commandprompt.com>
Date: Mon, 24 Nov 2014 16:55:50 +0300
Subject: [PATCH 1/3] Add missing check on OOM in expand_dbname path of
 conninfo_array_parse().

---
 src/interfaces/libpq/fe-connect.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/src/interfaces/libpq/fe-connect.c b/src/interfaces/libpq/fe-connect.c
new file mode 100644
index 3fe8c21..d7f2ec2
*** a/src/interfaces/libpq/fe-connect.c
--- b/src/interfaces/libpq/fe-connect.c
*************** conninfo_array_parse(const char *const *
*** 4402,4407 ****
--- 4402,4415 ----
  								if (options[k].val)
  									free(options[k].val);
  								options[k].val = strdup(str_option->val);
+ 								if (!options[k].val)
+ 								{
+ 									printfPQExpBuffer(errorMessage,
+ 													  libpq_gettext("out of memory\n"));
+ 									PQconninfoFree(options);
+ 									PQconninfoFree(dbname_options);
+ 									return NULL;
+ 								}
  								break;
  							}
  						}
-- 
2.1.0

diff --git a/src/interfaces/libpq/fe-connect.c b/src/interfaces/libpq/fe-connect.c
index 3fe8c21..d4d8c3b 100644
--- a/src/interfaces/libpq/fe-connect.c
+++ b/src/interfaces/libpq/fe-connect.c
@@ -333,7 +333,7 @@ static int	connectDBStart(PGconn *conn);
 static int	connectDBComplete(PGconn *conn);
 static PGPing internal_ping(PGconn *conn);
 static PGconn *makeEmptyPGconn(void);
-static void fillPGconn(PGconn *conn, PQconninfoOption *connOptions);
+static bool fillPGconn(PGconn *conn, PQconninfoOption *connOptions);
 static void freePGconn(PGconn *conn);
 static void closePGconn(PGconn *conn);
 static PQconninfoOption *conninfo_init(PQExpBuffer errorMessage);
@@ -585,7 +585,11 @@ PQconnectStartParams(const char *const * keywords,
 	/*
 	 * Move option values into conn structure
 	 */
-	fillPGconn(conn, connOptions);
+	if (!fillPGconn(conn, connOptions))
+	{
+		PQconninfoFree(connOptions);
+		return conn;
+	}
 
 	/*
 	 * Free the option info - all is in conn now
@@ -665,19 +669,19 @@ PQconnectStart(const char *conninfo)
 	return conn;
 }
 
-static void
+/*
+ * Move option values into conn structure
+ *
+ * Don't put anything cute here --- intelligence should be in
+ * connectOptions2 ...
+ *
+ * Returns true on success. On failure, returns false and sets error message.
+ */
+static bool
 fillPGconn(PGconn *conn, PQconninfoOption *connOptions)
 {
 	const internalPQconninfoOption *option;
 
-	/*
-	 * Move option values into conn structure
-	 *
-	 * Don't put anything cute here --- intelligence should be in
-	 * connectOptions2 ...
-	 *
-	 * XXX: probably worth checking strdup() return value here...
-	 */
 	for (option = PQconninfoOptions; option->keyword; option++)
 	{
 		const char *tmp = conninfo_getval(connOptions, option->keyword);
@@ -688,9 +692,22 @@ fillPGconn(PGconn *conn, PQconninfoOption *connOptions)
 
 			if (*connmember)
 				free(*connmember);
-			*connmember = tmp ? strdup(tmp) : NULL;
+			if (tmp)
+			{
+				*connmember = strdup(tmp);
+				if (*connmember == NULL)
+				{
+					printfPQExpBuffer(&conn->errorMessage,
+									  libpq_gettext("out of memory\n"));
+					return false;
+				}
+			}
+			else
+				*connmember = NULL;
 		}
 	}
+
+	return true;
 }
 
 /*
@@ -723,7 +740,12 @@ connectOptions1(PGconn *conn, const char *conninfo)
 	/*
 	 * Move option values into conn structure
 	 */
-	fillPGconn(conn, connOptions);
+	if (!fillPGconn(conn, connOptions))
+	{
+		conn->status = CONNECTION_BAD;
+		PQconninfoFree(connOptions);
+		return false;
+	}
 
 	/*
 	 * Free the option info - all is in conn now
@@ -753,6 +775,8 @@ connectOptions2(PGconn *conn)
 		if (conn->dbName)
 			free(conn->dbName);
 		conn->dbName = strdup(conn->pguser);
+		if (!conn->dbName)
+			goto oom_error;
 	}
 
 	/*
@@ -765,7 +789,12 @@ connectOptions2(PGconn *conn)
 		conn->pgpass = PasswordFromFile(conn->pghost, conn->pgport,
 										conn->dbName, conn->pguser);
 		if (conn->pgpass == NULL)
+		{
 			conn->pgpass = strdup(DefaultPassword);
+			if (!conn->pgpass)
+				goto oom_error;
+
+		}
 		else
 			conn->dot_pgpass_used = true;
 	}
@@ -823,7 +852,11 @@ connectOptions2(PGconn *conn)
 #endif
 	}
 	else
+	{
 		conn->sslmode = strdup(DefaultSSLMode);
+		if (!conn->sslmode)
+			goto oom_error;
+	}
 
 	/*
 	 * Resolve special "auto" client_encoding from the locale
@@ -833,6 +866,8 @@ connectOptions2(PGconn *conn)
 	{
 		free(conn->client_encoding_initial);
 		conn->client_encoding_initial = strdup(pg_encoding_to_char(pg_get_encoding_from_locale(NULL, true)));
+		if (!conn->client_encoding_initial)
+			goto oom_error;
 	}
 
 	/*
@@ -843,6 +878,13 @@ connectOptions2(PGconn *conn)
 	conn->options_valid = true;
 
 	return true;
+
+oom_error:
+	conn->options_valid = false;
+	conn->status = CONNECTION_BAD;
+	printfPQExpBuffer(&conn->errorMessage,
+					  libpq_gettext("out of memory\n"));
+	return false;
 }
 
 /*
@@ -937,6 +979,8 @@ PQsetdbLogin(const char *pghost, const char *pgport, const char *pgoptions,
 			if (conn->dbName)
 				free(conn->dbName);
 			conn->dbName = strdup(dbName);
+			if (!conn->dbName)
+				goto oom_error;
 		}
 	}
 
@@ -949,6 +993,8 @@ PQsetdbLogin(const char *pghost, const char *pgport, const char *pgoptions,
 		if (conn->pghost)
 			free(conn->pghost);
 		conn->pghost = strdup(pghost);
+		if (!conn->pghost)
+			goto oom_error;
 	}
 
 	if (pgport && pgport[0] != '\0')
@@ -956,6 +1002,8 @@ PQsetdbLogin(const char *pghost, const char *pgport, const char *pgoptions,
 		if (conn->pgport)
 			free(conn->pgport);
 		conn->pgport = strdup(pgport);
+		if (!conn->pgport)
+			goto oom_error;
 	}
 
 	if (pgoptions && pgoptions[0] != '\0')
@@ -963,6 +1011,8 @@ PQsetdbLogin(const char *pghost, const char *pgport, const char *pgoptions,
 		if (conn->pgoptions)
 			free(conn->pgoptions);
 		conn->pgoptions = strdup(pgoptions);
+		if (!conn->pgoptions)
+			goto oom_error;
 	}
 
 	if (pgtty && pgtty[0] != '\0')
@@ -970,6 +1020,8 @@ PQsetdbLogin(const char *pghost, const char *pgport, const char *pgoptions,
 		if (conn->pgtty)
 			free(conn->pgtty);
 		conn->pgtty = strdup(pgtty);
+		if (!conn->pgtty)
+			goto oom_error;
 	}
 
 	if (login && login[0] != '\0')
@@ -977,6 +1029,8 @@ PQsetdbLogin(const char *pghost, const char *pgport, const char *pgoptions,
 		if (conn->pguser)
 			free(conn->pguser);
 		conn->pguser = strdup(login);
+		if (!conn->pguser)
+			goto oom_error;
 	}
 
 	if (pwd && pwd[0] != '\0')
@@ -984,6 +1038,8 @@ PQsetdbLogin(const char *pghost, const char *pgport, const char *pgoptions,
 		if (conn->pgpass)
 			free(conn->pgpass);
 		conn->pgpass = strdup(pwd);
+		if (!conn->pgpass)
+			goto oom_error;
 	}
 
 	/*
@@ -999,6 +1055,12 @@ PQsetdbLogin(const char *pghost, const char *pgport, const char *pgoptions,
 		(void) connectDBComplete(conn);
 
 	return conn;
+
+oom_error:
+	conn->status = CONNECTION_BAD;
+	printfPQExpBuffer(&conn->errorMessage,
+					  libpq_gettext("out of memory\n"));
+	return false;
 }
 
 
@@ -3760,7 +3822,16 @@ ldapServiceLookup(const char *purl, PQconninfoOption *options,
 				if (strcmp(options[i].keyword, optname) == 0)
 				{
 					if (options[i].val == NULL)
+					{
 						options[i].val = strdup(optval);
+						if (!options[i].val)
+						{
+							printfPQExpBuffer(errorMessage,
+											libpq_gettext("out of memory\n"));
+							free(result);
+							return 3;
+						}
+					}
 					found_keyword = true;
 					break;
 				}
@@ -3983,6 +4054,13 @@ parseServiceFile(const char *serviceFile,
 					{
 						if (options[i].val == NULL)
 							options[i].val = strdup(val);
+						if (!options[i].val)
+						{
+							printfPQExpBuffer(errorMessage,
+											libpq_gettext("out of memory\n"));
+							fclose(f);
+							return 3;
+						}
 						found_keyword = true;
 						break;
 					}
@@ -4402,6 +4480,14 @@ conninfo_array_parse(const char *const * keywords, const char *const * values,
 								if (options[k].val)
 									free(options[k].val);
 								options[k].val = strdup(str_option->val);
+								if (!options[k].val)
+								{
+									printfPQExpBuffer(errorMessage,
+													  libpq_gettext("out of memory\n"));
+									PQconninfoFree(options);
+									PQconninfoFree(dbname_options);
+									return NULL;
+								}
 								break;
 							}
 						}
@@ -4596,20 +4682,22 @@ conninfo_uri_parse_options(PQconninfoOption *options, const char *uri,
 {
 	int			prefix_len;
 	char	   *p;
-	char	   *buf = strdup(uri);		/* need a modifiable copy of the input
-										 * URI */
-	char	   *start = buf;
+	char	   *buf;
+	char	   *start;
 	char		prevchar = '\0';
 	char	   *user = NULL;
 	char	   *host = NULL;
 	bool		retval = false;
 
+	/* need a modifiable copy of the input URI */
+	buf = strdup(uri);
 	if (buf == NULL)
 	{
 		printfPQExpBuffer(errorMessage,
 						  libpq_gettext("out of memory\n"));
 		return false;
 	}
+	start = buf;
 
 	/* Skip the URI prefix */
 	prefix_len = uri_prefix_length(uri);
@@ -4951,15 +5039,17 @@ conninfo_uri_parse_params(char *params,
 static char *
 conninfo_uri_decode(const char *str, PQExpBuffer errorMessage)
 {
-	char	   *buf = malloc(strlen(str) + 1);
-	char	   *p = buf;
+	char	   *buf;
+	char	   *p;
 	const char *q = str;
 
+	buf = malloc(strlen(str) + 1);
 	if (buf == NULL)
 	{
 		printfPQExpBuffer(errorMessage, libpq_gettext("out of memory\n"));
 		return NULL;
 	}
+	p = buf;
 
 	for (;;)
 	{
@@ -5104,7 +5194,6 @@ conninfo_storeval(PQconninfoOption *connOptions,
 	else
 	{
 		value_copy = strdup(value);
-
 		if (value_copy == NULL)
 		{
 			printfPQExpBuffer(errorMessage, libpq_gettext("out of memory\n"));
@@ -5672,6 +5761,12 @@ PasswordFromFile(char *hostname, char *port, char *dbname, char *username)
 		ret = strdup(t);
 		fclose(fp);
 
+		if (!ret)
+		{
+			/* Out of memory. XXX: an error message would be nice. */
+			return NULL;
+		}
+
 		/* De-escape password. */
 		for (p1 = p2 = ret; *p1 != ':' && *p1 != '\0'; ++p1, ++p2)
 		{