extern int parse_tag_buffer(struct tag *item, const void *data, unsigned long size);
extern int parse_tag(struct tag *item);
extern struct object *deref_tag(struct object *, const char *, int);
extern int parse_tag_buffer(struct tag *item, const void *data, unsigned long size);
extern int parse_tag(struct tag *item);
extern struct object *deref_tag(struct object *, const char *, int);