uuid.c File Reference

#include "config.h"
#include "uuid.h"
#include "UpnpInet.h"
#include "UpnpStdInt.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>

Include dependency graph for uuid.c:

Data Structures
struct	uuid_state

Macros
#define	CHECK(f1, f2)

Functions
static int	read_state (uint16_t *clockseq, uuid_time_t *timestamp, uuid_node_t *node)
	Read UUID generator state from non-volatile store.
static void	write_state (uint16_t clockseq, uuid_time_t timestamp, uuid_node_t node)
	Save UUID generator state back to non-volatile storage.
static void	format_uuid_v1 (uuid_upnp *uid, uint16_t clock_seq, uuid_time_t timestamp, uuid_node_t node)
	Make a UUID from the timestamp, clockseq, and node ID.
static void	format_uuid_v3 (uuid_upnp *uid, unsigned char hash[16])
	Make a UUID from a (pseudo)random 128 bit number.
static void	get_current_time (uuid_time_t *timestamp)
	Get time as 60 bit 100ns ticks since whenever.
static uint16_t	true_random (void)
	generate a crypto-quality random number. This sample doesn't do that.
int	uuid_create (uuid_upnp *uid)
	Generator of a UUID.
void	upnp_uuid_unpack (uuid_upnp *u, char *out)
	Out will be xxxx-xx-xx-xx-xxxxxx format.
void	uuid_create_from_name (uuid_upnp *uid, uuid_upnp nsid, void *name, int namelen)
	Create a UUID using a "name" from a "name space".
int	uuid_compare (uuid_upnp *u1, uuid_upnp *u2)
	Compare two UUID's "lexically" and return.

Variables
static uuid_state	st
static int	stateInited = 0

Macro Definition Documentation

CHECK

#define CHECK	(		f1,
			f2 )

Value:

        if (f1 != f2) \
                return f1 < f2 ? -1 : 1;

Function Documentation

format_uuid_v1()

void format_uuid_v1 ( uuid_upnp * uid, uint16_t clockseq, uuid_time_t timestamp, uuid_node_t node )

static

Make a UUID from the timestamp, clockseq, and node ID.

References _uuid_upnp::clock_seq_hi_and_reserved, _uuid_upnp::clock_seq_low, _uuid_upnp::node, _uuid_upnp::time_hi_and_version, _uuid_upnp::time_low, and _uuid_upnp::time_mid.

Referenced by uuid_create().

format_uuid_v3()

void format_uuid_v3 ( uuid_upnp * uid, unsigned char hash[16] )

static

Make a UUID from a (pseudo)random 128 bit number.

References _uuid_upnp::clock_seq_hi_and_reserved, _uuid_upnp::time_hi_and_version, _uuid_upnp::time_low, and _uuid_upnp::time_mid.

Referenced by uuid_create_from_name().

get_current_time()

void get_current_time ( uuid_time_t * timestamp )

static

Get time as 60 bit 100ns ticks since whenever.

Compensate for the fact that real clock resolution is less than 100ns.

References get_system_time(), and UUIDS_PER_TICK.

Referenced by uuid_create().

read_state()

int read_state ( uint16_t * clockseq, uuid_time_t * timestamp, uuid_node_t * node )

static

Read UUID generator state from non-volatile store.

References uuid_state::cs.

Referenced by uuid_create().

true_random()

uint16_t true_random ( void )

static

generate a crypto-quality random number. This sample doesn't do that.

References get_system_time(), and UUIDS_PER_TICK.

Referenced by uuid_create().

upnp_uuid_unpack()

void upnp_uuid_unpack	(	uuid_upnp *	u,
		char *	out )

Out will be xxxx-xx-xx-xx-xxxxxx format.

Parameters

u	.
out	.

References _uuid_upnp::clock_seq_hi_and_reserved, _uuid_upnp::clock_seq_low, _uuid_upnp::node, _uuid_upnp::time_hi_and_version, _uuid_upnp::time_low, and _uuid_upnp::time_mid.

uuid_compare()

int uuid_compare	(	uuid_upnp *	u1,
		uuid_upnp *	u2 )

Compare two UUID's "lexically" and return.

Compare two UUID's "lexically".

• -1: u1 is lexically before u2
• 0: u1 is equal to u2
• 1: u1 is lexically after u2

Note: Lexical ordering is not temporal ordering!

Parameters

u1	.
u2	.

References _uuid_upnp::clock_seq_hi_and_reserved, _uuid_upnp::clock_seq_low, _uuid_upnp::node, _uuid_upnp::time_hi_and_version, _uuid_upnp::time_low, and _uuid_upnp::time_mid.

uuid_create()

int uuid_create

(

uuid_upnp *

uid

)

Generator of a UUID.

Generate a UUID.

Parameters

uid

.

References format_uuid_v1(), get_current_time(), get_ieee_node_identifier(), read_state(), true_random(), and write_state().

uuid_create_from_name()

void uuid_create_from_name	(	uuid_upnp *	uid,
		uuid_upnp	nsid,
		void *	name,
		int	namelen )

Create a UUID using a "name" from a "name space".

Parameters

uid	resulting UUID.
nsid	UUID to serve as context, so identical names from different name spaces generate different UUIDs.
name	The name from which to generate a UUID.
namelen	The length of the name.

References format_uuid_v3(), _uuid_upnp::time_hi_and_version, _uuid_upnp::time_low, and _uuid_upnp::time_mid.

write_state()

void write_state ( uint16_t clockseq, uuid_time_t timestamp, uuid_node_t node )

static

Save UUID generator state back to non-volatile storage.

Referenced by uuid_create().