From 02daccd6e7cec96df59a6f43276323b5255997fb Mon Sep 17 00:00:00 2001
From: Greg Smith <greg@2ndQuadrant.com>
Date: Wed, 23 Feb 2011 06:44:10 -0500
Subject: [PATCH] Wrap use of PQconnectdbParams, add proper error checking and
 logging when the connection fails.

---
 dbutils.c | 20 ++++++++++++++++++++
 dbutils.h |  3 +++
 repmgr.c  | 26 ++++++++++----------------
 3 files changed, 33 insertions(+), 16 deletions(-)

diff --git a/dbutils.c b/dbutils.c
index 37b938d1..da712a73 100644
--- a/dbutils.c
+++ b/dbutils.c
@@ -43,6 +43,26 @@ establishDBConnection(const char *conninfo, const bool exit_on_error)
 	return conn;
 }
 
+PGconn *
+establishDBConnectionByParams(const char *keywords[], const char *values[],const bool exit_on_error)
+{
+	/* Make a connection to the database */
+	PGconn *conn = PQconnectdbParams(keywords, values, true);
+
+	/* Check to see that the backend connection was successfully made */
+	if ((PQstatus(conn) != CONNECTION_OK))
+	{
+		log_err(_("Connection to database failed: %s\n"),
+		        PQerrorMessage(conn));
+		if (exit_on_error)
+		{
+			PQfinish(conn);
+			exit(ERR_DB_CON);
+		}
+	}
+
+	return conn;
+}
 
 bool
 is_standby(PGconn *conn)
diff --git a/dbutils.h b/dbutils.h
index 45d0ea96..7eb68ed6 100644
--- a/dbutils.h
+++ b/dbutils.h
@@ -21,6 +21,9 @@
 #define _REPMGR_DBUTILS_H_
 
 PGconn *establishDBConnection(const char *conninfo, const bool exit_on_error);
+PGconn *establishDBConnectionByParams(const char *keywords[],
+                                      const char *values[],
+                                      const bool exit_on_error);
 bool	is_standby(PGconn *conn);
 char   *pg_version(PGconn *conn, char* major_version);
 bool	guc_setted(PGconn *conn, const char *parameter, const char *op,
diff --git a/repmgr.c b/repmgr.c
index e058bad4..baae4b26 100644
--- a/repmgr.c
+++ b/repmgr.c
@@ -732,13 +732,7 @@ do_standby_clone(void)
 
 	/* We need to connect to check configuration and start a backup */
 	log_info(_("%s connecting to master database\n"), progname);
-	conn = PQconnectdbParams(keywords, values, true);
-	if (!conn)
-	{
-		log_err(_("%s: could not connect to master\n"),
-		        progname);
-		exit(ERR_BAD_CONFIG);
-	}
+	conn=establishDBConnectionByParams(keywords,values,true);
 
 	/* primary should be v9 or better */
 	log_info(_("%s connected to master, checking its state\n"), progname);
@@ -1011,17 +1005,17 @@ do_standby_clone(void)
 	}
 
 stop_backup:
-	/* inform the master that we have finished the backup */
-	conn = PQconnectdbParams(keywords, values, true);
-	if (!conn)
-	{
-		log_err(_("%s: could not connect to master\n"),
-		        progname);
-		exit(ERR_BAD_RSYNC);
-	}
+
+	/*
+	 * Inform the master that we have finished the backup.
+	 *
+	 * Don't have this one exit if it fails, so that a more informative
+	 * error message will also appear about the backup not being stopped.
+	 */
+	log_info(_("%s connecting to master database to stop backup\n"), progname);
+	conn=establishDBConnectionByParams(keywords,values,false);
 
 	log_notice("Finishing backup...\n");
-
 	sqlquery_snprintf(sqlquery, "SELECT pg_xlogfile_name(pg_stop_backup())");
 	log_debug("standby clone: %s\n", sqlquery);