Add a SECURITY LABEL command.

This is intended as infrastructure to support integration with label-based
mandatory access control systems such as SE-Linux. Further changes (mostly
hooks) will be needed, but this is a big chunk of it.

KaiGai Kohei and Robert Haas

src/include/commands/seclabel.h

@@ -0,0 +1,35 @@
+/*
+ * seclabel.h
+ *
+ * Prototypes for functions in commands/seclabel.c
+ *
+ * Portions Copyright (c) 1996-2010, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ */
+#ifndef SECLABEL_H
+#define SECLABEL_H
+
+#include "catalog/objectaddress.h"
+#include "nodes/primnodes.h"
+#include "nodes/parsenodes.h"
+
+/*
+ * Internal APIs
+ */
+extern char *GetSecurityLabel(const ObjectAddress *object,
+				 const char *provider);
+extern void SetSecurityLabel(const ObjectAddress *object,
+			     const char *provider, const char *label);
+extern void DeleteSecurityLabel(const ObjectAddress *object);
+
+/*
+ * Statement and ESP hook support
+ */
+extern void ExecSecLabelStmt(SecLabelStmt *stmt);
+
+typedef void (*check_object_relabel_type)(const ObjectAddress *object,
+										  const char *seclabel);
+extern void register_label_provider(const char *provider,
+								    check_object_relabel_type hook);
+
+#endif	/* SECLABEL_H */