From 7cf2af6f321201406eae1baf585c6bbd23745478 Mon Sep 17 00:00:00 2001
From: Steve Singer <steve@ssinger.info>
Date: Mon, 21 May 2018 10:13:21 -0400
Subject: [PATCH] 1. Add an option to slonik to disable the version check   
 against the slony schema

2. Add an option to make the remote listener use a
   READ COMMITTED instead of a serialized deferrable
   transaction

3. If slonik was not compiled with pgport then allow
   PG_HOME to override/set the location of the share directory
   containing the slony .sql files

Patches from Tom Tignor<ttignor@akamai.com>.
---
 src/slon/confoptions.c   | 23 +++++++++++++++++++++++
 src/slon/confoptions.h   |  2 ++
 src/slon/dbutils.c       |  6 ++++++
 src/slon/remote_listen.c | 29 +++++------------------------
 src/slonik/slonik.c      | 12 +++++++++++-
 5 files changed, 47 insertions(+), 25 deletions(-)

diff --git a/src/slon/confoptions.c b/src/slon/confoptions.c
index 56de55a7..4eb6b855 100644
--- a/src/slon/confoptions.c
+++ b/src/slon/confoptions.c
@@ -262,6 +262,29 @@ static struct config_bool ConfigureNamesBool[] =
 		&monitor_threads,
 		true
 	},
+	{
+	{
+			(const char *) "enable_version_check",
+			gettext_noop("Should services check release versions "
+			"and fail on differences?"),
+			NULL,
+			SLON_C_BOOL,
+                },
+		&enable_version_check,
+		true
+	},
+	{
+		{
+			(const char *) "remote_listen_serializable_transactions",
+			gettext_noop("Determines if the remote listener should use serializable transactions. "
+				"This setting trades between strict isolation and avoiding blocking "
+				"for lock management."),
+			NULL,
+			SLON_C_BOOL,
+		},
+		&remote_listen_serializable_transactions,
+		true
+	},
 	{{0}}
 };
 
diff --git a/src/slon/confoptions.h b/src/slon/confoptions.h
index 75bfbfba..63c5c8f4 100644
--- a/src/slon/confoptions.h
+++ b/src/slon/confoptions.h
@@ -26,6 +26,8 @@ extern int	desired_sync_time;
 extern int	quit_sync_provider;
 extern int	quit_sync_finalsync;
 extern bool keep_alive;
+extern bool     enable_version_check;
+extern bool 	remote_listen_serializable_transactions;
 extern int	keep_alive_idle;
 extern int	keep_alive_interval;
 extern int	keep_alive_count;
diff --git a/src/slon/dbutils.c b/src/slon/dbutils.c
index 8450b44b..f223f0c8 100644
--- a/src/slon/dbutils.c
+++ b/src/slon/dbutils.c
@@ -31,6 +31,7 @@
 #include "slon.h"
 
 bool		keep_alive;
+bool		enable_version_check;
 int			keep_alive_idle;
 int			keep_alive_count;
 int			keep_alive_interval;
@@ -389,6 +390,11 @@ db_checkSchemaVersion(PGconn *conn)
 	PGresult   *res;
 	int			retval = 0;
 
+	if (! enable_version_check)
+	{
+		return 0;
+	}
+
 	/*
 	 * Select the version number from the schema
 	 */
diff --git a/src/slon/remote_listen.c b/src/slon/remote_listen.c
index 3ba6151a..48a103f4 100644
--- a/src/slon/remote_listen.c
+++ b/src/slon/remote_listen.c
@@ -61,6 +61,7 @@ static int	poll_sleep;
 
 extern char *lag_interval;
 int			remote_listen_timeout;
+bool        remote_listen_serializable_transactions;
 
 static int	sel_max_events = 0;
 
@@ -295,30 +296,10 @@ remoteListenThread_main(void *cdata)
 			}
 			if (PQserverVersion(dbconn) >= 90100)
 			{
-				slon_mkquery(&query1, "SET SESSION CHARACTERISTICS AS TRANSACTION read only deferrable");
-				res = PQexec(dbconn, dstring_data(&query1));
-				if (PQresultStatus(res) != PGRES_COMMAND_OK)
-				{
-					slon_log(SLON_ERROR,
-							 "remoteListenThread_%d: \"%s\" - %s",
-							 node->no_id,
-						   dstring_data(&query1), PQresultErrorMessage(res));
-					PQclear(res);
-					slon_disconnectdb(conn);
-					free(conn_conninfo);
-					conn = NULL;
-					conn_conninfo = NULL;
-					rc = sched_msleep(node, pa_connretry * 1000);
-					if (rc != SCHED_STATUS_OK && rc != SCHED_STATUS_CANCEL)
-						break;
-
-					continue;
-				}
-
-			}
-			if (PQserverVersion(dbconn) >= 90100)
-			{
-				slon_mkquery(&query1, "SET SESSION CHARACTERISTICS AS TRANSACTION read only isolation level serializable deferrable");
+				char buf[200];
+				sprintf(buf, "SET SESSION CHARACTERISTICS AS TRANSACTION read only isolation level %s",
+				remote_listen_serializable_transactions ? "serializable deferrable" : "repeatable read");
+				slon_mkquery(&query1, buf);
 				res = PQexec(dbconn, dstring_data(&query1));
 				if (PQresultStatus(res) != PGRES_COMMAND_OK)
 				{
diff --git a/src/slonik/slonik.c b/src/slonik/slonik.c
index 001557b9..bd125707 100644
--- a/src/slonik/slonik.c
+++ b/src/slonik/slonik.c
@@ -223,8 +223,18 @@ main(int argc, const char *argv[])
                 get_share_path(myfull_path, share_path);
         }
 #else
-	strcpy(share_path, PGSHARE);
+	char *pgHome = getenv("PG_HOME");
+	if (pgHome)
+	{
+		snprintf(share_path, MAXPGPATH-1, "%s/share", pgHome);
+		share_path[MAXPGPATH-1] = '\0';
+	} 
+	else 
+	{
+		strcpy(share_path, PGSHARE);
+	}
 #endif
+printf("Share path is %s\n",share_path);
 
 	if (optind < argc)
 	{
-- 
2.39.5