uuid.h File Reference

Specification (from draft-leach-uuids-guids-01.txt ) More...

#include "sal/config.h"
#include "rtl/string.h"
#include "sal/saldllapi.h"
#include "sal/types.h"

Go to the source code of this file.

Macros
#define	RTL_UUID_NAMESPACE_DNS
	namespace DNS More...
#define	RTL_UUID_NAMESPACE_URL
	namespace URL More...
#define	RTL_UUID_NAMESPACE_OID
	namespace oid More...
#define	RTL_UUID_NAMESPACE_X500
	namespace X500 More...

Functions
SAL_DLLPUBLIC void	rtl_createUuid (sal_uInt8 *pTargetUUID, const sal_uInt8 *pPredecessorUUID, sal_Bool bUseEthernetAddress)
	Generates a new Version 4 (random number based) UUID (Universally Unique IDentifier). More...
SAL_DLLPUBLIC sal_Int32	rtl_compareUuid (const sal_uInt8 *pUUID1, const sal_uInt8 *pUUID2)
	Compare two UUID's lexically. More...
SAL_DLLPUBLIC void	rtl_createNamedUuid (sal_uInt8 *pTargetUUID, const sal_uInt8 *pNameSpaceUUID, const rtl_String *pName)
	Creates named UUIDs. More...

Detailed Description

Specification (from draft-leach-uuids-guids-01.txt )

A UUID is an identifier that is unique across both space and time, with respect to the space of all UUIDs. To be precise, the UUID consists of a finite bit space. Thus, collision cannot be avoided in principle. A UUID can be used for multiple purposes, from tagging objects with an extremely short lifetime, to reliably identifying very persistent objects across a network.

The generation of UUIDs does not require that a registration authority be contacted for each identifier. Instead, Version 4 UUIDs are generated from (pseudo unique) sequences of (pseudo) random bits.

Macro Definition Documentation

RTL_UUID_NAMESPACE_DNS

#define RTL_UUID_NAMESPACE_DNS

Value:

{\
      0x6b,0xa7,0xb8,0x10,\
      0x9d,0xad,\
      0x11,0xd1,\
      0x80, 0xb4, 0x00, 0xc0, 0x4f, 0xd4, 0x30, 0xc8\
    }

namespace DNS

(Use them the following way : sal_uInt8 aNsDNS[16]) = RTL_UUID_NAMESPACE_DNS;

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RTL_UUID_NAMESPACE_OID

#define RTL_UUID_NAMESPACE_OID

Value:

{\
      0x6b, 0xa7, 0xb8, 0x12,\
      0x9d, 0xad,\
      0x11, 0xd1,\
      0x80, 0xb4, 0x00, 0xc0, 0x4f, 0xd4, 0x30, 0xc8\
    }

namespace oid

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RTL_UUID_NAMESPACE_URL

#define RTL_UUID_NAMESPACE_URL

Value:

{ \
      0x6b, 0xa7, 0xb8, 0x11,\
      0x9d, 0xad,\
      0x11, 0xd1,\
      0x80, 0xb4, 0x00, 0xc0, 0x4f, 0xd4, 0x30, 0xc8\
    }

namespace URL

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RTL_UUID_NAMESPACE_X500

#define RTL_UUID_NAMESPACE_X500

Value:

{\
      0x6b, 0xa7, 0xb8, 0x14,\
      0x9d, 0xad,\
      0x11, 0xd1,\
      0x80, 0xb4, 0x00, 0xc0, 0x4f, 0xd4, 0x30, 0xc8\
    }

namespace X500

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Function Documentation

rtl_compareUuid()

SAL_DLLPUBLIC sal_Int32 rtl_compareUuid	(	const sal_uInt8 *	pUUID1,
		const sal_uInt8 *	pUUID2
	)

Compare two UUID's lexically.

Note: lexical ordering is not temporal ordering!

Note: For equalnesschecking, a memcmp(pUUID1,pUUID2,16) is more efficient

Returns

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

rtl_createNamedUuid()

SAL_DLLPUBLIC void rtl_createNamedUuid	(	sal_uInt8 *	pTargetUUID,
		const sal_uInt8 *	pNameSpaceUUID,
		const rtl_String *	pName
	)

Creates named UUIDs.

The version 3 UUID is meant for generating UUIDs from names that are drawn from, and unique within, some name space. Some examples of names (and, implicitly, name spaces) might be DNS names, URLs, ISO Object IDs (OIDs), reserved words in a programming language, or X.500 Distinguished Names (DNs); thus, the concept of name and name space should be broadly construed, and not limited to textual names.

The requirements for such UUIDs are as follows:

• The UUIDs generated at different times from the same name in the same namespace MUST be equal

• The UUIDs generated from two different names in the same namespace should be different (with very high probability)

• The UUIDs generated from the same name in two different namespaces should be different with (very high probability)

• If two UUIDs that were generated from names are equal, then they were generated from the same name in the same namespace (with very high probability).

Parameters

pTargetUUID	pointer to at least 16 bytes of memory. After the call it contains the newly generated uuid in network byte order.
pNameSpaceUUID	The namespace uuid. Below are some predefined ones, but any arbitrary uuid can be used as namespace.
pName	the name

rtl_createUuid()

SAL_DLLPUBLIC void rtl_createUuid	(	sal_uInt8 *	pTargetUUID,
		const sal_uInt8 *	pPredecessorUUID,
		sal_Bool	bUseEthernetAddress
	)

Generates a new Version 4 (random number based) UUID (Universally Unique IDentifier).

Parameters

pTargetUUID	pointer to at least 16 bytes of memory. After the call it contains the newly generated uuid in network byte order.
pPredecessorUUID	ignored (was used when this function returned Version 1 instead of Version 4 UUIDs).
bUseEthernetAddress	ignored (was used when this function returned Version 1 instead of Version 4 UUIDs).