sdp_key_t
sdp_add_key(sdp_key_t **key, const char *method, const char *enckey)
*key = calloc(1, sizeof (sdp_key_t));
sdp_key_t *m_key;
sdp_key_t *s_key;
extern int sdp_add_key(sdp_key_t **, const char *, const char *);
sdp_parse_key(sdp_key_t **key, const char *begin, const char *end,
sdp_key_t *new_key;
new_key = calloc(1, sizeof (sdp_key_t));
extern void sdp_free_key(sdp_key_t *);
sdp_free_key(sdp_key_t *key)