[libxml2]Add libxml2 library

libxml2/include/private/entities.h

@@ -0,0 +1,24 @@
+#ifndef XML_ENTITIES_H_PRIVATE__
+#define XML_ENTITIES_H_PRIVATE__
+
+#include <libxml/tree.h>
+#include <libxml/xmlstring.h>
+
+/*
+ * Entity flags
+ *
+ * XML_ENT_PARSED: The entity was parsed and `children` points to the
+ * content.
+ *
+ * XML_ENT_CHECKED: The entity was checked for loops and amplification.
+ * expandedSize was set.
+ *
+ * XML_ENT_VALIDATED: The entity contains a valid attribute value.
+ * Only used when entities aren't substituted.
+ */
+#define XML_ENT_PARSED      (1u << 0)
+#define XML_ENT_CHECKED     (1u << 1)
+#define XML_ENT_VALIDATED   (1u << 2)
+#define XML_ENT_EXPANDING   (1u << 3)
+
+#endif /* XML_ENTITIES_H_PRIVATE__ */