55 lines
1.9 KiB
C
55 lines
1.9 KiB
C
/****************************************************************************
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* libs/libc/uuid/lib_uuid_hash.c
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*
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* Licensed to the Apache Software Foundation (ASF) under one or more
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* contributor license agreements. See the NOTICE file distributed with
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* this work for additional information regarding copyright ownership. The
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* ASF licenses this file to you under the Apache License, Version 2.0 (the
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* "License"); you may not use this file except in compliance with the
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* License. You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
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* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
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* License for the specific language governing permissions and limitations
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* under the License.
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*
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****************************************************************************/
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/****************************************************************************
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* Included Files
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****************************************************************************/
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#include <uuid.h>
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/****************************************************************************
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* Public Functions
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****************************************************************************/
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/****************************************************************************
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* uuid_hash
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*
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* Description:
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* Generate a hash value.
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*
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* See also:
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* http://www.opengroup.org/onlinepubs/009629399/uuid_hash.htm
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*
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****************************************************************************/
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uint16_t uuid_hash(FAR const uuid_t *u, FAR uint32_t *status)
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{
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if (status)
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{
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*status = uuid_s_ok;
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}
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/* Use the most frequently changing bits in the UUID as the hash
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* value. This should yield a good enough distribution...
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*/
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return u ? u->time_low & 0xffff : 0;
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}
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