Add comments, use strncmp, clean up GUC desc.

Good to go!

src/backend/distributed/executor/multi_utility.c

@@ -409,6 +409,12 @@ multi_ProcessUtility(Node *parsetree,
 }
 
 
+/*
+ * SkipCitusProcessingForUtility simply returns whether a given utility should
+ * bypass Citus processing and checks and be handled exclusively by standard
+ * PostgreSQL utility processing. At present, CREATE/ALTER/DROP EXTENSION,
+ * ABORT, COMMIT, ROLLBACK, and SET (GUC) statements are exempt from Citus.
+ */
 static bool
 SkipCitusProcessingForUtility(Node *parsetree)
 {
@@ -460,6 +466,11 @@ SkipCitusProcessingForUtility(Node *parsetree)
 }
 
 
+/*
+ * IsCitusExtensionStmt returns whether a given utility is a CREATE or ALTER
+ * EXTENSION statement which references the citus extension. This function
+ * returns false for all other inputs.
+ */
 static bool
 IsCitusExtensionStmt(Node *parsetree)
 {
@@ -1370,6 +1381,11 @@ ErrorIfUnstableCreateOrAlterExtensionStmt(Node *parsetree)
 }
 
 
+/*
+ * ExtractNewExtensionVersion returns the new extension version specified by
+ * a CREATE or ALTER EXTENSION statement. Other inputs are not permitted. This
+ * function returns NULL for statements with no explicit version specified.
+ */
 static char *
 ExtractNewExtensionVersion(Node *parsetree)
 {
@@ -1394,8 +1410,7 @@ ExtractNewExtensionVersion(Node *parsetree)
 	foreach(optionsCell, optionsList)
 	{
 		DefElem *defElement = (DefElem *) lfirst(optionsCell);
-
+		if (strncmp(defElement->defname, "new_version", NAMEDATALEN) == 0)
-		if (strcmp(defElement->defname, "new_version") == 0)
 		{
 			newVersion = strVal(defElement->arg);
 			break;

src/backend/distributed/shared_library_init.c

@@ -615,7 +615,7 @@ RegisterCitusConfigVariables(void)
 
 	DefineCustomStringVariable(
 		"citus.version",
-		gettext_noop("Shows the running Citus version"),
+		gettext_noop("Shows the Citus library version"),
 		NULL,
 		&CitusVersion,
 		CITUS_VERSION,
@@ -625,7 +625,7 @@ RegisterCitusConfigVariables(void)
 
 	DefineCustomBoolVariable(
 		"citus.enable_version_checks",
-		gettext_noop("Enables version checks in CREATE/ALTER extension queries"),
+		gettext_noop("Enables version checks during CREATE/ALTER EXTENSION commands"),
 		NULL,
 		&EnableVersionChecks,
 		true,