xref: /freebsd/lib/libc/uuid/uuid.3 (revision dc41de36abc01cd19d43347e14f077b26d183665)

.\" Copyright (c) 2002 Marcel Moolenaar
.\" Copyright (c) 2002 Hiten Mahesh Pandya
.\" All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
.\" BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
.\" LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
.\" AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
.\" OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.Dd November 19, 2021
.Dt UUID 3
.Os
.Sh NAME
.Nm uuid_compare ,
.Nm uuid_create ,
.Nm uuid_create_nil ,
.Nm uuid_equal ,
.Nm uuid_from_string ,
.Nm uuid_hash ,
.Nm uuid_is_nil ,
.Nm uuid_to_string
.Nd DCE 1.1 compliant UUID functions
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In uuid.h
.Ft int32_t
.Fn uuid_compare "const uuid_t *uuid1" "const uuid_t *uuid2" "uint32_t *status"
.Ft void
.Fn uuid_create "uuid_t *uuid" "uint32_t *status"
.Ft void
.Fn uuid_create_nil "uuid_t *uuid" "uint32_t *status"
.Ft int32_t
.Fn uuid_equal "const uuid_t *uuid1" "const uuid_t *uuid2" "uint32_t *status"
.Ft void
.Fn uuid_from_string "const char *str" "uuid_t *uuid" "uint32_t *status"
.Ft uint16_t
.Fn uuid_hash "const uuid_t *uuid" "uint32_t *status"
.Ft int32_t
.Fn uuid_is_nil "const uuid_t *uuid" "uint32_t *status"
.Ft void
.Fn uuid_to_string "const uuid_t *uuid" "char **str" "uint32_t *status"
.Ft void
.Fn uuid_enc_le "void *buf" "const uuid_t *uuid"
.Ft void
.Fn uuid_dec_le "const void *buf" "uuid_t *"
.Ft void
.Fn uuid_enc_be "void *buf" "const uuid_t *uuid"
.Ft void
.Fn uuid_dec_be "const void *buf" "uuid_t *"
.Sh DESCRIPTION
The family of DCE 1.1 compliant UUID functions allow applications to operate
on universally unique identifiers, or UUIDs.
The
.Fn uuid_create
and
.Fn uuid_create_nil
functions create UUIDs.
To convert from the binary representation to the string representation or
vice versa, use
.Fn uuid_to_string
or
.Fn uuid_from_string
respectively.
.Pp
The
.Fn uuid_to_string
function set
.Fa *str
to be a pointer to a buffer sufficiently large to hold the string.
This pointer should be passed to
.Xr free 3
to release the allocated storage when it is no longer needed.
.Pp
The
.Fn uuid_enc_le
and
.Fn uuid_enc_be
functions encode a binary representation of a UUID into an octet stream
in little-endian and big-endian byte-order, respectively.
The destination buffer must be pre-allocated by the caller, and must be
large enough to hold the 16-octet binary UUID.
These routines are not part of the DCE RPC API.
They are provided for convenience.
.Pp
The
.Fn uuid_dec_le
and
.Fn uuid_dec_be
functions decode a UUID from an octet stream in little-endian and
big-endian byte-order, respectively.
These routines are not part of the DCE RPC API.
They are provided for convenience.
.Pp
The
.Fn uuid_compare
and
.Fn uuid_equal
functions compare two UUIDs for equality.
UUIDs are equal if pointers
.Fa a
and
.Fa b
are equal or both
.Dv NULL ,
or if the structures
.Fa a
and
.Fa b
point to are equal.
.Fn uuid_compare
returns 0 if the UUIDs are equal, -1 if
.Fa a
is less than
.Fa b ,
and 1 if
.Fa a
is greater than
.Fa b .
.Fn uuid_equal
returns 1 if the UUIDs are equal, 0 if they are
not equal.
.Pp
The
.Fn uuid_is_nil
function compares a UUID to
.Dv NULL .
The function returns 1 if
.Fa u
is
.Dv NULL
or if the UUID consists of all zeros, and zero otherwise.
.Pp
The
.Fn uuid_hash
function returns a 16-bit hash value for the specified UUID.
.Sh RETURN VALUES
The successful or unsuccessful completion of the function is returned in
the
.Fa status
argument.
Possible values are:
.Bl -tag -width ".Dv uuid_s_invalid_string_uuid"
.It Dv uuid_s_ok
The function completed successfully.
.It Dv uuid_s_bad_version
The UUID does not have a known version.
.It Dv uuid_s_invalid_string_uuid
The string representation of an UUID is not valid.
.It Dv uuid_s_no_memory
The function can not allocate memory to store an UUID representation.
.El
.Pp
.Fn uuid_compare ,
.Fn uuid_equal ,
.Fn uuid_is_nil ,
and
.Fn uuid_hash
always set
.Fa status
to
.Dv uuid_s_ok .
.Sh SEE ALSO
.Xr uuidgen 1 ,
.Xr uuidgen 2
.Sh STANDARDS
The UUID functions conform to the DCE 1.1 RPC specification.
.Sh BUGS
This manpage can be improved.