1.\" $OpenBSD: hashinit.9,v 1.9 2016/09/24 18:59:04 tedu Exp $ 2.\" 3.\" Copyright (c) 2001 Tobias Weingartner 4.\" All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 3. The name of the author may not be used to endorse or promote products 15.\" derived from this software without specific prior written permission. 16.\" 17.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 18.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 19.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 20.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 21.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 22.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27.\" 28.Dd $Mdocdate: September 24 2016 $ 29.Dt HASHINIT 9 30.Os 31.Sh NAME 32.Nm hashinit , 33.Nm hashfree 34.Nd kernel hashtable functions 35.Sh SYNOPSIS 36.In sys/systm.h 37.Ft void * 38.Fn hashinit "int num" "int type" "int flags" "u_long *mask" 39.Ft void 40.Fn hashfree "void *hash" "int num" "int type" 41.Sh DESCRIPTION 42The 43.Fn hashinit 44function is used to allocate a hashtable of a desired size given by the 45.Fa num 46argument. 47The 48.Fn hashinit 49function will round this number to the next power of two, and 50allocate and initialize the requested hashtable. 51The 52.Fa type 53and 54.Fa flags 55arguments are passed to the 56.Xr malloc 9 57function unchanged. 58The 59.Fa mask 60argument is used to pass back the mask for use with the allocated 61hashing table. 62.Pp 63The 64.Fn hashfree 65function causes memory allocated by the 66.Fn hashinit 67function to be released. 68The 69.Fa num 70and 71.Fa type 72arguments of related calls must match. 73.Sh RETURN VALUES 74The 75.Fn hashinit 76function returns a pointer to the allocated and initialized hash table. 77.Sh SEE ALSO 78.Xr free 9 , 79.Xr malloc 9 80.Sh LIMITATIONS 81The 82.Fn hashinit 83function currently only allocates hash tables with LIST bucket pointers 84at this time. 85Future enhancements to allocate QUEUE bucket pointers may be warranted. 86This may necessitate an API change to accommodate. 87.Sh HISTORY 88The 89.Nm 90function first appeared in 91.Bx 4.4 . 92