Ensure variable values are quoted when necessary while sending down SET

comamnds to the remote nodes

Earlier we'd special cased a few GUCs such as those using memory or time units
or transaction isolation levels. But clearly that wasn't enough as we noticed
with "application_name" recently. So fix this problem in a more comprehensive
manner.

Added a few more test cases to cover these scenarios.

6 files changed, 139 insertions, 47 deletions

diff --git a/src/backend/pgxc/pool/execRemote.c b/src/backend/pgxc/pool/execRemote.c
index 321fa1fee2..d6e842301e 100644
--- a/src/backend/pgxc/pool/execRemote.c
+++ b/src/backend/pgxc/pool/execRemote.c
@@ -1912,7 +1912,7 @@ pgxc_node_begin(int conn_count, PGXCNodeHandle **connections,
 
 	/* Send virtualXID to the remote nodes using SET command */
 	sprintf(lxid, "%d", MyProc->lxid);
-	PGXCNodeSetParam(true, "coordinator_lxid", lxid);
+	PGXCNodeSetParam(true, "coordinator_lxid", lxid, 0);
 
 	/* after transactions are started send down local set commands */
 	init_str = PGXCNodeGetTransactionParamStr();
diff --git a/src/backend/pgxc/pool/pgxcnode.c b/src/backend/pgxc/pool/pgxcnode.c
index 28a5bbb4c6..4375e8813a 100644
--- a/src/backend/pgxc/pool/pgxcnode.c
+++ b/src/backend/pgxc/pool/pgxcnode.c
@@ -107,6 +107,7 @@ typedef struct
 {
 	NameData name;
 	NameData value;
+	int		 flags;
 } ParamEntry;
 
 
@@ -2568,7 +2569,7 @@ paramlist_delete_param(List *param_list, const char *name)
  * values on newly connected remote nodes.
  */
 void
-PGXCNodeSetParam(bool local, const char *name, const char *value)
+PGXCNodeSetParam(bool local, const char *name, const char *value, int flags)
 {
 	List *param_list;
 	MemoryContext oldcontext;
@@ -2596,6 +2597,7 @@ PGXCNodeSetParam(bool local, const char *name, const char *value)
 		entry = (ParamEntry *) palloc(sizeof (ParamEntry));
 		strlcpy((char *) (&entry->name), name, NAMEDATALEN);
 		strlcpy((char *) (&entry->value), value, NAMEDATALEN);
+		entry->flags = flags;
 
 		param_list = lappend(param_list, entry);
 	}
@@ -2647,25 +2649,6 @@ PGXCNodeResetParams(bool only_local)
 	local_params = NULL;
 }
 
-
-#ifdef NOT_USED
-static char *
-quote_ident_cstr(char *rawstr)
-{
-	text       *rawstr_text;
-	text       *result_text;
-	char       *result;
-
-	rawstr_text = cstring_to_text(rawstr);
-	result_text = DatumGetTextP(DirectFunctionCall1(quote_ident,
-													PointerGetDatum(rawstr_text)));
-	result = text_to_cstring(result_text);
-
-	return result;
-}
-#endif
-
-
 static void
 get_set_command(List *param_list, StringInfo command, bool local)
 {
@@ -2682,6 +2665,8 @@ get_set_command(List *param_list, StringInfo command, bool local)
 		if (strlen(value) == 0)
 			value = "''";
 
+		value = quote_guc_value(value, entry->flags);
+
 		appendStringInfo(command, "SET %s %s TO %s;", local ? "LOCAL" : "",
 			 NameStr(entry->name), value);
 	}
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index eaeaadb9cd..ff26c2e2c7 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -5650,13 +5650,9 @@ AtEOXact_GUC(bool isCommit, int nestLevel)
 				/* XXX perhaps this should use is_missing=false, not sure */
 				newvalStr = GetConfigOptionByName(gconf->name, NULL, true);
 
-				/*
-				 * Quote value if it is including memory or time units
-				 */
-				if (newvalStr && (gconf->flags & (GUC_UNIT_MEMORY | GUC_UNIT_TIME)))
-					newvalStr = quote_identifier(newvalStr);
 				if (newvalStr)
-					PGXCNodeSetParam((stack->state == GUC_LOCAL), gconf->name, newvalStr);
+					PGXCNodeSetParam((stack->state == GUC_LOCAL), gconf->name,
+							newvalStr, gconf->flags);
 			}
 
 			/* Finish popping the state stack */
@@ -6981,38 +6977,24 @@ set_config_option(const char *name, const char *value,
 		initStringInfo(&poolcmd);
 
 		/*
-		 * We are getting parse error when sending down
-		 * SET transaction_isolation TO read committed;
-		 * XXX generic solution?
-		 */
-		if (value && strcmp("transaction_isolation", name) == 0)
-			value = quote_identifier(value);
-
-		if (value && strcmp("default_transaction_isolation", name) == 0)
-			value = quote_identifier(value);
-
-		/*
-		 * Quote value if it is including memory or time units
-		 */
-		if (value && (record->flags & (GUC_UNIT_MEMORY | GUC_UNIT_TIME)))
-			value = quote_identifier(value);
-
-		/*
 		 * Save new parameter value with the node manager.
 		 * XXX here we may check: if value equals to configuration default
 		 * just reset parameter instead. Minus one table entry, shorter SET
 		 * command sent downn... Sounds like optimization.
 		 */
+
 		if (action == GUC_ACTION_LOCAL)
 		{
 			if (IsTransactionBlock())
-				PGXCNodeSetParam(true, name, value);
+				PGXCNodeSetParam(true, name, value, record->flags);
+			value = quote_guc_value(value, record->flags);
 			appendStringInfo(&poolcmd, "SET LOCAL %s TO %s", name,
 					(value ? value : "DEFAULT"));
 		}
 		else
 		{
-			PGXCNodeSetParam(false, name, value);
+			PGXCNodeSetParam(false, name, value, record->flags);
+			value = quote_guc_value(value, record->flags);
 			appendStringInfo(&poolcmd, "SET %s TO %s", name,
 					(value ? value : "DEFAULT"));
 		}
@@ -10940,4 +10922,31 @@ check_storm_catalog_remap_string(char **newval, void **extra, GucSource source)
 	return true;
 }
 #endif
+
+#ifdef XCP
+/*
+ * Return a quoted GUC value, when necessary
+ */
+char *
+quote_guc_value(const char *value, int flags)
+{
+	if (value == NULL)
+		return value;
+
+	/*
+	 * If the GUC rceives list input, then the individual elements in the list
+	 * must be already quoted correctly by flatten_set_variable_args(). We must
+	 * not quote the entire value again
+	 */
+	if (flags & GUC_LIST_INPUT)
+	   return value;
+
+	/*
+	 * Otherwise quote the value. quote_identifier() takes care of correctly
+	 * quoting the value when needed, including GUC_UNIT_MEMORY and
+	 * GUC_UNIT_TIME values.
+	 */
+	return quote_identifier(value);
+}
+#endif
 #include "guc-file.c"
diff --git a/src/include/pgxc/pgxcnode.h b/src/include/pgxc/pgxcnode.h
index f40120671f..7ad15c7c6a 100644
--- a/src/include/pgxc/pgxcnode.h
+++ b/src/include/pgxc/pgxcnode.h
@@ -187,7 +187,8 @@ extern void add_error_message(PGXCNodeHandle * handle, const char *message);
 
 extern Datum pgxc_execute_on_nodes(int numnodes, Oid *nodelist, char *query);
 
-extern void PGXCNodeSetParam(bool local, const char *name, const char *value);
+extern void PGXCNodeSetParam(bool local, const char *name, const char *value,
+				int flags);
 extern void PGXCNodeResetParams(bool only_local);
 extern char *PGXCNodeGetSessionParamStr(void);
 extern char *PGXCNodeGetTransactionParamStr(void);
diff --git a/src/include/utils/guc.h b/src/include/utils/guc.h
index a831fa2777..9fb76be629 100644
--- a/src/include/utils/guc.h
+++ b/src/include/utils/guc.h
@@ -446,5 +446,6 @@ extern void assign_search_path(const char *newval, void *extra);
 /* in access/transam/xlog.c */
 extern bool check_wal_buffers(int *newval, void **extra, GucSource source);
 extern void assign_xlog_sync_method(int new_sync_method, void *extra);
+extern char *quote_guc_value(const char *value, int flags);
 
 #endif   /* GUC_H */
diff --git a/src/test/regress/sql/guc.sql b/src/test/regress/sql/guc.sql
index 95ac9cb43b..60133f1891 100644
--- a/src/test/regress/sql/guc.sql
+++ b/src/test/regress/sql/guc.sql
@@ -209,3 +209,99 @@ set default_text_search_config = no_such_config;
 select func_with_bad_set();
 
 reset check_function_bodies;
+
+SET application_name TO "special name";
+CREATE TABLE testtab (a int);
+INSERT INTO testtab VALUES (1), (2), (3);
+SELECT * FROM testtab;
+DROP TABLE testtab;
+
+SET default_transaction_isolation TO "read committed";
+CREATE TABLE testtab (a int);
+INSERT INTO testtab VALUES (1), (2), (3);
+SELECT * FROM testtab;
+DROP TABLE testtab;
+
+SET work_mem TO '64kB';
+CREATE TABLE testtab (a int);
+INSERT INTO testtab VALUES (1), (2), (3);
+SELECT * FROM testtab;
+DROP TABLE testtab;
+
+SET work_mem TO "64kB";
+CREATE TABLE testtab (a int);
+INSERT INTO testtab VALUES (1), (2), (3);
+SELECT * FROM testtab;
+DROP TABLE testtab;
+
+SET log_min_duration_statement = '1s';
+CREATE TABLE testtab (a int);
+INSERT INTO testtab VALUES (1), (2), (3);
+SELECT * FROM testtab;
+DROP TABLE testtab;
+
+CREATE SCHEMA testschema;
+CREATE SCHEMA "testschema 2";
+CREATE SCHEMA "testschema 3";
+CREATE SCHEMA READ;
+CREATE SCHEMA "READ";
+
+-- ERROR
+CREATE SCHEMA SELECT;
+
+-- Ok
+CREATE SCHEMA "SELECT";
+
+SET search_path TO testschema;
+CREATE TABLE testtab (a int);
+\d+ testtab
+INSERT INTO testtab VALUES (1), (2), (3);
+SELECT * FROM testtab;
+DROP TABLE testtab;
+
+SET search_path TO "testschema";
+CREATE TABLE testtab (a int);
+\d+ testtab
+INSERT INTO testtab VALUES (1), (2), (3);
+SELECT * FROM testtab;
+DROP TABLE testtab;
+
+SET search_path TO testschema, "testschema 2";
+CREATE TABLE testtab (a int);
+\d+ testtab
+INSERT INTO testtab VALUES (1), (2), (3);
+SELECT * FROM testtab;
+DROP TABLE testtab;
+
+SET search_path TO "testschema 3", "testschema 2";
+CREATE TABLE testtab (a int);
+\d+ testtab
+INSERT INTO testtab VALUES (1), (2), (3);
+SELECT * FROM testtab;
+DROP TABLE testtab;
+
+-- ERROR
+SET search_path TO "testschema 3", SELECT;
+
+SET search_path TO "SELECT", "testschema 3";
+CREATE TABLE testtab (a int);
+\d+ testtab
+CREATE TABLE "testschema 3".testtab (a int);
+\d+ testtab
+INSERT INTO "testschema 3".testtab VALUES (1), (2), (3);
+INSERT INTO "SELECT".testtab VALUES (4);
+SELECT * FROM "testschema 3".testtab;
+INSERT INTO testtab SELECT * FROM "testschema 3".testtab;
+SELECT * FROM "testschema 3".testtab;
+\d+ testtab
+SELECT * FROM testtab;
+INSERT INTO testtab SELECT * FROM testtab;
+SELECT * FROM testtab;
+DROP TABLE testtab;
+
+DROP SCHEMA testschema CASCADE;
+DROP SCHEMA "testschema 2" CASCADE;
+DROP SCHEMA "testschema 3" CASCADE;
+DROP SCHEMA "READ" CASCADE;
+DROP SCHEMA SELECT CASCADE;
+DROP SCHEMA "SELECT" CASCADE;