extern struct tag *lookup_tag(const unsigned char *sha1);
extern int parse_tag_buffer(struct tag *item, void *data, unsigned long size);
extern int parse_tag(struct tag *item);
extern struct tag *lookup_tag(const unsigned char *sha1);
extern int parse_tag_buffer(struct tag *item, void *data, unsigned long size);
extern int parse_tag(struct tag *item);