text: #ifndef GUID_H
  #define GUID_H
  
  #define GUID_128_SIZE 16
  typedef uint8_t guid_128_t[GUID_128_SIZE];
  
  #define GUID_128_HOST_HASH_SIZE 4
  
  ARRAY_DEFINE_TYPE(guid_128_t, guid_128_t);
  
  enum uuid_format {
  	FORMAT_RECORD,
  	FORMAT_COMPACT,
  	FORMAT_MICROSOFT,
  };
  /* Generate a GUID (contains host name) */
  const char *guid_generate(void);
  /* Generate 128 bit GUID */
  void guid_128_generate(guid_128_t guid_r);
  /* Returns TRUE if GUID is empty (not set / unknown). */
  bool guid_128_is_empty(const guid_128_t guid) ATTR_PURE;
  static inline void guid_128_empty(guid_128_t guid)
  {
  	memset(guid, 0, GUID_128_SIZE);
  }
  /* Returns TRUE if two GUIDs are equal. */
  bool guid_128_equals(const guid_128_t guid1, const guid_128_t guid2) ATTR_PURE;
  /* Copy GUID */
  static inline void guid_128_copy(guid_128_t dest, const guid_128_t src)
  {
  	memcpy(dest, src, GUID_128_SIZE);
  }
  
  /* Returns GUID as a hex string. */
  const char *guid_128_to_string(const guid_128_t guid);
  /* Parse GUID from a string. Returns 0 if ok, -1 if GUID isn't valid. */
  int guid_128_from_string(const char *str, guid_128_t guid_r);
  
  /* Returns GUID as a UUID hex string. */
  const char *guid_128_to_uuid_string(const guid_128_t guid, enum uuid_format format);
  /* Parse GUID from a UUID string. Returns 0 if ok, -1 if UUID isn't valid. */
  int guid_128_from_uuid_string(const char *str, guid_128_t guid_r);
  
  /* guid_128 hash/cmp functions for hash.h */
  unsigned int guid_128_hash(const guid_128_t guid) ATTR_PURE;
  int guid_128_cmp(const guid_128_t guid1, const guid_128_t guid2) ATTR_PURE;
  
  /* Return the hash of host used by guid_128_generate(). */
  void guid_128_host_hash_get(const char *host,
  			    unsigned char hash_r[STATIC_ARRAY GUID_128_HOST_HASH_SIZE]);
  
  #endif
  