xref: /xnu-12377.1.9/bsd/net/flowhash.h (revision f6217f891ac0bb64f3d375211650a4c1ff8ca1ea)
1*f6217f89SApple OSS Distributions /*
2*f6217f89SApple OSS Distributions  * Copyright (c) 2011 Apple Inc. All rights reserved.
3*f6217f89SApple OSS Distributions  *
4*f6217f89SApple OSS Distributions  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5*f6217f89SApple OSS Distributions  *
6*f6217f89SApple OSS Distributions  * This file contains Original Code and/or Modifications of Original Code
7*f6217f89SApple OSS Distributions  * as defined in and that are subject to the Apple Public Source License
8*f6217f89SApple OSS Distributions  * Version 2.0 (the 'License'). You may not use this file except in
9*f6217f89SApple OSS Distributions  * compliance with the License. The rights granted to you under the License
10*f6217f89SApple OSS Distributions  * may not be used to create, or enable the creation or redistribution of,
11*f6217f89SApple OSS Distributions  * unlawful or unlicensed copies of an Apple operating system, or to
12*f6217f89SApple OSS Distributions  * circumvent, violate, or enable the circumvention or violation of, any
13*f6217f89SApple OSS Distributions  * terms of an Apple operating system software license agreement.
14*f6217f89SApple OSS Distributions  *
15*f6217f89SApple OSS Distributions  * Please obtain a copy of the License at
16*f6217f89SApple OSS Distributions  * http://www.opensource.apple.com/apsl/ and read it before using this file.
17*f6217f89SApple OSS Distributions  *
18*f6217f89SApple OSS Distributions  * The Original Code and all software distributed under the License are
19*f6217f89SApple OSS Distributions  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20*f6217f89SApple OSS Distributions  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21*f6217f89SApple OSS Distributions  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22*f6217f89SApple OSS Distributions  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23*f6217f89SApple OSS Distributions  * Please see the License for the specific language governing rights and
24*f6217f89SApple OSS Distributions  * limitations under the License.
25*f6217f89SApple OSS Distributions  *
26*f6217f89SApple OSS Distributions  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27*f6217f89SApple OSS Distributions  */
28*f6217f89SApple OSS Distributions 
29*f6217f89SApple OSS Distributions #ifndef _NET_FLOWHASH_H_
30*f6217f89SApple OSS Distributions #define _NET_FLOWHASH_H_
31*f6217f89SApple OSS Distributions 
32*f6217f89SApple OSS Distributions #include <sys/types.h>
33*f6217f89SApple OSS Distributions 
34*f6217f89SApple OSS Distributions #ifdef  __cplusplus
35*f6217f89SApple OSS Distributions extern "C" {
36*f6217f89SApple OSS Distributions #endif
37*f6217f89SApple OSS Distributions 
38*f6217f89SApple OSS Distributions /*
39*f6217f89SApple OSS Distributions  * If 32-bit hash value is too large, use this macro to truncate
40*f6217f89SApple OSS Distributions  * it to n-bit; masking is a faster operation than modulus.
41*f6217f89SApple OSS Distributions  */
42*f6217f89SApple OSS Distributions #define HASHMASK(n)     ((1UL << (n)) - 1)
43*f6217f89SApple OSS Distributions 
44*f6217f89SApple OSS Distributions /*
45*f6217f89SApple OSS Distributions  * Returns 32-bit hash value.  Hashes which are capable of returning
46*f6217f89SApple OSS Distributions  * more bits currently have their results truncated to 32-bit.
47*f6217f89SApple OSS Distributions  */
48*f6217f89SApple OSS Distributions typedef u_int32_t net_flowhash_fn_t(const void *__sized_by(len) key, u_int32_t len, const u_int32_t);
49*f6217f89SApple OSS Distributions 
50*f6217f89SApple OSS Distributions extern net_flowhash_fn_t *net_flowhash;
51*f6217f89SApple OSS Distributions extern net_flowhash_fn_t net_flowhash_mh3_x86_32;
52*f6217f89SApple OSS Distributions extern net_flowhash_fn_t net_flowhash_mh3_x64_128;
53*f6217f89SApple OSS Distributions extern net_flowhash_fn_t net_flowhash_jhash;
54*f6217f89SApple OSS Distributions #ifdef  __cplusplus
55*f6217f89SApple OSS Distributions }
56*f6217f89SApple OSS Distributions #endif
57*f6217f89SApple OSS Distributions 
58*f6217f89SApple OSS Distributions #endif /* _NET_FLOWHASH_H_ */
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